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1 #
2 # (C) Copyright 2000 - 2013
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4 #
5 # SPDX-License-Identifier: GPL-2.0+
6 #
7
8 Summary:
9 ========
10
11 This directory contains the source code for U-Boot, a boot loader for
12 Embedded boards based on PowerPC, ARM, MIPS and several other
13 processors, which can be installed in a boot ROM and used to
14 initialize and test the hardware or to download and run application
15 code.
16
17 The development of U-Boot is closely related to Linux: some parts of
18 the source code originate in the Linux source tree, we have some
19 header files in common, and special provision has been made to
20 support booting of Linux images.
21
22 Some attention has been paid to make this software easily
23 configurable and extendable. For instance, all monitor commands are
24 implemented with the same call interface, so that it's very easy to
25 add new commands. Also, instead of permanently adding rarely used
26 code (for instance hardware test utilities) to the monitor, you can
27 load and run it dynamically.
28
29
30 Status:
31 =======
32
33 In general, all boards for which a configuration option exists in the
34 Makefile have been tested to some extent and can be considered
35 "working". In fact, many of them are used in production systems.
36
37 In case of problems see the CHANGELOG and CREDITS files to find out
38 who contributed the specific port. The boards.cfg file lists board
39 maintainers.
40
41 Note: There is no CHANGELOG file in the actual U-Boot source tree;
42 it can be created dynamically from the Git log using:
43
44 make CHANGELOG
45
46
47 Where to get help:
48 ==================
49
50 In case you have questions about, problems with or contributions for
51 U-Boot you should send a message to the U-Boot mailing list at
52 <u-boot@lists.denx.de>. There is also an archive of previous traffic
53 on the mailing list - please search the archive before asking FAQ's.
54 Please see http://lists.denx.de/pipermail/u-boot and
55 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
56
57
58 Where to get source code:
59 =========================
60
61 The U-Boot source code is maintained in the git repository at
62 git://www.denx.de/git/u-boot.git ; you can browse it online at
63 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
64
65 The "snapshot" links on this page allow you to download tarballs of
66 any version you might be interested in. Official releases are also
67 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
68 directory.
69
70 Pre-built (and tested) images are available from
71 ftp://ftp.denx.de/pub/u-boot/images/
72
73
74 Where we come from:
75 ===================
76
77 - start from 8xxrom sources
78 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
79 - clean up code
80 - make it easier to add custom boards
81 - make it possible to add other [PowerPC] CPUs
82 - extend functions, especially:
83 * Provide extended interface to Linux boot loader
84 * S-Record download
85 * network boot
86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
87 - create ARMBoot project (http://sourceforge.net/projects/armboot)
88 - add other CPU families (starting with ARM)
89 - create U-Boot project (http://sourceforge.net/projects/u-boot)
90 - current project page: see http://www.denx.de/wiki/U-Boot
91
92
93 Names and Spelling:
94 ===================
95
96 The "official" name of this project is "Das U-Boot". The spelling
97 "U-Boot" shall be used in all written text (documentation, comments
98 in source files etc.). Example:
99
100 This is the README file for the U-Boot project.
101
102 File names etc. shall be based on the string "u-boot". Examples:
103
104 include/asm-ppc/u-boot.h
105
106 #include <asm/u-boot.h>
107
108 Variable names, preprocessor constants etc. shall be either based on
109 the string "u_boot" or on "U_BOOT". Example:
110
111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
113
114
115 Versioning:
116 ===========
117
118 Starting with the release in October 2008, the names of the releases
119 were changed from numerical release numbers without deeper meaning
120 into a time stamp based numbering. Regular releases are identified by
121 names consisting of the calendar year and month of the release date.
122 Additional fields (if present) indicate release candidates or bug fix
123 releases in "stable" maintenance trees.
124
125 Examples:
126 U-Boot v2009.11 - Release November 2009
127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
129
130
131 Directory Hierarchy:
132 ====================
133
134 /arch Architecture specific files
135 /arc Files generic to ARC architecture
136 /cpu CPU specific files
137 /arc700 Files specific to ARC 700 CPUs
138 /lib Architecture specific library files
139 /arm Files generic to ARM architecture
140 /cpu CPU specific files
141 /arm720t Files specific to ARM 720 CPUs
142 /arm920t Files specific to ARM 920 CPUs
143 /at91 Files specific to Atmel AT91RM9200 CPU
144 /imx Files specific to Freescale MC9328 i.MX CPUs
145 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
146 /arm926ejs Files specific to ARM 926 CPUs
147 /arm1136 Files specific to ARM 1136 CPUs
148 /pxa Files specific to Intel XScale PXA CPUs
149 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
150 /lib Architecture specific library files
151 /avr32 Files generic to AVR32 architecture
152 /cpu CPU specific files
153 /lib Architecture specific library files
154 /blackfin Files generic to Analog Devices Blackfin architecture
155 /cpu CPU specific files
156 /lib Architecture specific library files
157 /m68k Files generic to m68k architecture
158 /cpu CPU specific files
159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
164 /lib Architecture specific library files
165 /microblaze Files generic to microblaze architecture
166 /cpu CPU specific files
167 /lib Architecture specific library files
168 /mips Files generic to MIPS architecture
169 /cpu CPU specific files
170 /mips32 Files specific to MIPS32 CPUs
171 /mips64 Files specific to MIPS64 CPUs
172 /lib Architecture specific library files
173 /nds32 Files generic to NDS32 architecture
174 /cpu CPU specific files
175 /n1213 Files specific to Andes Technology N1213 CPUs
176 /lib Architecture specific library files
177 /nios2 Files generic to Altera NIOS2 architecture
178 /cpu CPU specific files
179 /lib Architecture specific library files
180 /openrisc Files generic to OpenRISC architecture
181 /cpu CPU specific files
182 /lib Architecture specific library files
183 /powerpc Files generic to PowerPC architecture
184 /cpu CPU specific files
185 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
186 /mpc5xx Files specific to Freescale MPC5xx CPUs
187 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
188 /mpc8xx Files specific to Freescale MPC8xx CPUs
189 /mpc824x Files specific to Freescale MPC824x CPUs
190 /mpc8260 Files specific to Freescale MPC8260 CPUs
191 /mpc85xx Files specific to Freescale MPC85xx CPUs
192 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
193 /lib Architecture specific library files
194 /sh Files generic to SH architecture
195 /cpu CPU specific files
196 /sh2 Files specific to sh2 CPUs
197 /sh3 Files specific to sh3 CPUs
198 /sh4 Files specific to sh4 CPUs
199 /lib Architecture specific library files
200 /sparc Files generic to SPARC architecture
201 /cpu CPU specific files
202 /leon2 Files specific to Gaisler LEON2 SPARC CPU
203 /leon3 Files specific to Gaisler LEON3 SPARC CPU
204 /lib Architecture specific library files
205 /x86 Files generic to x86 architecture
206 /cpu CPU specific files
207 /lib Architecture specific library files
208 /api Machine/arch independent API for external apps
209 /board Board dependent files
210 /common Misc architecture independent functions
211 /disk Code for disk drive partition handling
212 /doc Documentation (don't expect too much)
213 /drivers Commonly used device drivers
214 /dts Contains Makefile for building internal U-Boot fdt.
215 /examples Example code for standalone applications, etc.
216 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
217 /include Header Files
218 /lib Files generic to all architectures
219 /libfdt Library files to support flattened device trees
220 /lzma Library files to support LZMA decompression
221 /lzo Library files to support LZO decompression
222 /net Networking code
223 /post Power On Self Test
224 /spl Secondary Program Loader framework
225 /tools Tools to build S-Record or U-Boot images, etc.
226
227 Software Configuration:
228 =======================
229
230 Configuration is usually done using C preprocessor defines; the
231 rationale behind that is to avoid dead code whenever possible.
232
233 There are two classes of configuration variables:
234
235 * Configuration _OPTIONS_:
236 These are selectable by the user and have names beginning with
237 "CONFIG_".
238
239 * Configuration _SETTINGS_:
240 These depend on the hardware etc. and should not be meddled with if
241 you don't know what you're doing; they have names beginning with
242 "CONFIG_SYS_".
243
244 Later we will add a configuration tool - probably similar to or even
245 identical to what's used for the Linux kernel. Right now, we have to
246 do the configuration by hand, which means creating some symbolic
247 links and editing some configuration files. We use the TQM8xxL boards
248 as an example here.
249
250
251 Selection of Processor Architecture and Board Type:
252 ---------------------------------------------------
253
254 For all supported boards there are ready-to-use default
255 configurations available; just type "make <board_name>_defconfig".
256
257 Example: For a TQM823L module type:
258
259 cd u-boot
260 make TQM823L_defconfig
261
262 For the Cogent platform, you need to specify the CPU type as well;
263 e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent
264 directory according to the instructions in cogent/README.
265
266
267 Sandbox Environment:
268 --------------------
269
270 U-Boot can be built natively to run on a Linux host using the 'sandbox'
271 board. This allows feature development which is not board- or architecture-
272 specific to be undertaken on a native platform. The sandbox is also used to
273 run some of U-Boot's tests.
274
275 See board/sandbox/README.sandbox for more details.
276
277
278 Configuration Options:
279 ----------------------
280
281 Configuration depends on the combination of board and CPU type; all
282 such information is kept in a configuration file
283 "include/configs/<board_name>.h".
284
285 Example: For a TQM823L module, all configuration settings are in
286 "include/configs/TQM823L.h".
287
288
289 Many of the options are named exactly as the corresponding Linux
290 kernel configuration options. The intention is to make it easier to
291 build a config tool - later.
292
293
294 The following options need to be configured:
295
296 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
297
298 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
299
300 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
301 Define exactly one, e.g. CONFIG_ATSTK1002
302
303 - CPU Module Type: (if CONFIG_COGENT is defined)
304 Define exactly one of
305 CONFIG_CMA286_60_OLD
306 --- FIXME --- not tested yet:
307 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
308 CONFIG_CMA287_23, CONFIG_CMA287_50
309
310 - Motherboard Type: (if CONFIG_COGENT is defined)
311 Define exactly one of
312 CONFIG_CMA101, CONFIG_CMA102
313
314 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
315 Define one or more of
316 CONFIG_CMA302
317
318 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
319 Define one or more of
320 CONFIG_LCD_HEARTBEAT - update a character position on
321 the LCD display every second with
322 a "rotator" |\-/|\-/
323
324 - Marvell Family Member
325 CONFIG_SYS_MVFS - define it if you want to enable
326 multiple fs option at one time
327 for marvell soc family
328
329 - MPC824X Family Member (if CONFIG_MPC824X is defined)
330 Define exactly one of
331 CONFIG_MPC8240, CONFIG_MPC8245
332
333 - 8xx CPU Options: (if using an MPC8xx CPU)
334 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
335 get_gclk_freq() cannot work
336 e.g. if there is no 32KHz
337 reference PIT/RTC clock
338 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
339 or XTAL/EXTAL)
340
341 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
342 CONFIG_SYS_8xx_CPUCLK_MIN
343 CONFIG_SYS_8xx_CPUCLK_MAX
344 CONFIG_8xx_CPUCLK_DEFAULT
345 See doc/README.MPC866
346
347 CONFIG_SYS_MEASURE_CPUCLK
348
349 Define this to measure the actual CPU clock instead
350 of relying on the correctness of the configured
351 values. Mostly useful for board bringup to make sure
352 the PLL is locked at the intended frequency. Note
353 that this requires a (stable) reference clock (32 kHz
354 RTC clock or CONFIG_SYS_8XX_XIN)
355
356 CONFIG_SYS_DELAYED_ICACHE
357
358 Define this option if you want to enable the
359 ICache only when Code runs from RAM.
360
361 - 85xx CPU Options:
362 CONFIG_SYS_PPC64
363
364 Specifies that the core is a 64-bit PowerPC implementation (implements
365 the "64" category of the Power ISA). This is necessary for ePAPR
366 compliance, among other possible reasons.
367
368 CONFIG_SYS_FSL_TBCLK_DIV
369
370 Defines the core time base clock divider ratio compared to the
371 system clock. On most PQ3 devices this is 8, on newer QorIQ
372 devices it can be 16 or 32. The ratio varies from SoC to Soc.
373
374 CONFIG_SYS_FSL_PCIE_COMPAT
375
376 Defines the string to utilize when trying to match PCIe device
377 tree nodes for the given platform.
378
379 CONFIG_SYS_PPC_E500_DEBUG_TLB
380
381 Enables a temporary TLB entry to be used during boot to work
382 around limitations in e500v1 and e500v2 external debugger
383 support. This reduces the portions of the boot code where
384 breakpoints and single stepping do not work. The value of this
385 symbol should be set to the TLB1 entry to be used for this
386 purpose.
387
388 CONFIG_SYS_FSL_ERRATUM_A004510
389
390 Enables a workaround for erratum A004510. If set,
391 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
392 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
393
394 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
395 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
396
397 Defines one or two SoC revisions (low 8 bits of SVR)
398 for which the A004510 workaround should be applied.
399
400 The rest of SVR is either not relevant to the decision
401 of whether the erratum is present (e.g. p2040 versus
402 p2041) or is implied by the build target, which controls
403 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
404
405 See Freescale App Note 4493 for more information about
406 this erratum.
407
408 CONFIG_A003399_NOR_WORKAROUND
409 Enables a workaround for IFC erratum A003399. It is only
410 requred during NOR boot.
411
412 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
413
414 This is the value to write into CCSR offset 0x18600
415 according to the A004510 workaround.
416
417 CONFIG_SYS_FSL_DSP_DDR_ADDR
418 This value denotes start offset of DDR memory which is
419 connected exclusively to the DSP cores.
420
421 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
422 This value denotes start offset of M2 memory
423 which is directly connected to the DSP core.
424
425 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
426 This value denotes start offset of M3 memory which is directly
427 connected to the DSP core.
428
429 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
430 This value denotes start offset of DSP CCSR space.
431
432 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
433 Single Source Clock is clocking mode present in some of FSL SoC's.
434 In this mode, a single differential clock is used to supply
435 clocks to the sysclock, ddrclock and usbclock.
436
437 CONFIG_SYS_CPC_REINIT_F
438 This CONFIG is defined when the CPC is configured as SRAM at the
439 time of U-boot entry and is required to be re-initialized.
440
441 CONFIG_DEEP_SLEEP
442 Inidcates this SoC supports deep sleep feature. If deep sleep is
443 supported, core will start to execute uboot when wakes up.
444
445 - Generic CPU options:
446 CONFIG_SYS_GENERIC_GLOBAL_DATA
447 Defines global data is initialized in generic board board_init_f().
448 If this macro is defined, global data is created and cleared in
449 generic board board_init_f(). Without this macro, architecture/board
450 should initialize global data before calling board_init_f().
451
452 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
453
454 Defines the endianess of the CPU. Implementation of those
455 values is arch specific.
456
457 CONFIG_SYS_FSL_DDR
458 Freescale DDR driver in use. This type of DDR controller is
459 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
460 SoCs.
461
462 CONFIG_SYS_FSL_DDR_ADDR
463 Freescale DDR memory-mapped register base.
464
465 CONFIG_SYS_FSL_DDR_EMU
466 Specify emulator support for DDR. Some DDR features such as
467 deskew training are not available.
468
469 CONFIG_SYS_FSL_DDRC_GEN1
470 Freescale DDR1 controller.
471
472 CONFIG_SYS_FSL_DDRC_GEN2
473 Freescale DDR2 controller.
474
475 CONFIG_SYS_FSL_DDRC_GEN3
476 Freescale DDR3 controller.
477
478 CONFIG_SYS_FSL_DDRC_GEN4
479 Freescale DDR4 controller.
480
481 CONFIG_SYS_FSL_DDRC_ARM_GEN3
482 Freescale DDR3 controller for ARM-based SoCs.
483
484 CONFIG_SYS_FSL_DDR1
485 Board config to use DDR1. It can be enabled for SoCs with
486 Freescale DDR1 or DDR2 controllers, depending on the board
487 implemetation.
488
489 CONFIG_SYS_FSL_DDR2
490 Board config to use DDR2. It can be eanbeld for SoCs with
491 Freescale DDR2 or DDR3 controllers, depending on the board
492 implementation.
493
494 CONFIG_SYS_FSL_DDR3
495 Board config to use DDR3. It can be enabled for SoCs with
496 Freescale DDR3 or DDR3L controllers.
497
498 CONFIG_SYS_FSL_DDR3L
499 Board config to use DDR3L. It can be enabled for SoCs with
500 DDR3L controllers.
501
502 CONFIG_SYS_FSL_DDR4
503 Board config to use DDR4. It can be enabled for SoCs with
504 DDR4 controllers.
505
506 CONFIG_SYS_FSL_IFC_BE
507 Defines the IFC controller register space as Big Endian
508
509 CONFIG_SYS_FSL_IFC_LE
510 Defines the IFC controller register space as Little Endian
511
512 CONFIG_SYS_FSL_PBL_PBI
513 It enables addition of RCW (Power on reset configuration) in built image.
514 Please refer doc/README.pblimage for more details
515
516 CONFIG_SYS_FSL_PBL_RCW
517 It adds PBI(pre-boot instructions) commands in u-boot build image.
518 PBI commands can be used to configure SoC before it starts the execution.
519 Please refer doc/README.pblimage for more details
520
521 CONFIG_SPL_FSL_PBL
522 It adds a target to create boot binary having SPL binary in PBI format
523 concatenated with u-boot binary.
524
525 CONFIG_SYS_FSL_DDR_BE
526 Defines the DDR controller register space as Big Endian
527
528 CONFIG_SYS_FSL_DDR_LE
529 Defines the DDR controller register space as Little Endian
530
531 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
532 Physical address from the view of DDR controllers. It is the
533 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
534 it could be different for ARM SoCs.
535
536 CONFIG_SYS_FSL_DDR_INTLV_256B
537 DDR controller interleaving on 256-byte. This is a special
538 interleaving mode, handled by Dickens for Freescale layerscape
539 SoCs with ARM core.
540
541 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
542 Number of controllers used as main memory.
543
544 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
545 Number of controllers used for other than main memory.
546
547 CONFIG_SYS_FSL_SEC_BE
548 Defines the SEC controller register space as Big Endian
549
550 CONFIG_SYS_FSL_SEC_LE
551 Defines the SEC controller register space as Little Endian
552
553 - Intel Monahans options:
554 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
555
556 Defines the Monahans run mode to oscillator
557 ratio. Valid values are 8, 16, 24, 31. The core
558 frequency is this value multiplied by 13 MHz.
559
560 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
561
562 Defines the Monahans turbo mode to oscillator
563 ratio. Valid values are 1 (default if undefined) and
564 2. The core frequency as calculated above is multiplied
565 by this value.
566
567 - MIPS CPU options:
568 CONFIG_SYS_INIT_SP_OFFSET
569
570 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
571 pointer. This is needed for the temporary stack before
572 relocation.
573
574 CONFIG_SYS_MIPS_CACHE_MODE
575
576 Cache operation mode for the MIPS CPU.
577 See also arch/mips/include/asm/mipsregs.h.
578 Possible values are:
579 CONF_CM_CACHABLE_NO_WA
580 CONF_CM_CACHABLE_WA
581 CONF_CM_UNCACHED
582 CONF_CM_CACHABLE_NONCOHERENT
583 CONF_CM_CACHABLE_CE
584 CONF_CM_CACHABLE_COW
585 CONF_CM_CACHABLE_CUW
586 CONF_CM_CACHABLE_ACCELERATED
587
588 CONFIG_SYS_XWAY_EBU_BOOTCFG
589
590 Special option for Lantiq XWAY SoCs for booting from NOR flash.
591 See also arch/mips/cpu/mips32/start.S.
592
593 CONFIG_XWAY_SWAP_BYTES
594
595 Enable compilation of tools/xway-swap-bytes needed for Lantiq
596 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
597 be swapped if a flash programmer is used.
598
599 - ARM options:
600 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
601
602 Select high exception vectors of the ARM core, e.g., do not
603 clear the V bit of the c1 register of CP15.
604
605 CONFIG_SYS_THUMB_BUILD
606
607 Use this flag to build U-Boot using the Thumb instruction
608 set for ARM architectures. Thumb instruction set provides
609 better code density. For ARM architectures that support
610 Thumb2 this flag will result in Thumb2 code generated by
611 GCC.
612
613 CONFIG_ARM_ERRATA_716044
614 CONFIG_ARM_ERRATA_742230
615 CONFIG_ARM_ERRATA_743622
616 CONFIG_ARM_ERRATA_751472
617 CONFIG_ARM_ERRATA_794072
618 CONFIG_ARM_ERRATA_761320
619
620 If set, the workarounds for these ARM errata are applied early
621 during U-Boot startup. Note that these options force the
622 workarounds to be applied; no CPU-type/version detection
623 exists, unlike the similar options in the Linux kernel. Do not
624 set these options unless they apply!
625
626 - Linux Kernel Interface:
627 CONFIG_CLOCKS_IN_MHZ
628
629 U-Boot stores all clock information in Hz
630 internally. For binary compatibility with older Linux
631 kernels (which expect the clocks passed in the
632 bd_info data to be in MHz) the environment variable
633 "clocks_in_mhz" can be defined so that U-Boot
634 converts clock data to MHZ before passing it to the
635 Linux kernel.
636 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
637 "clocks_in_mhz=1" is automatically included in the
638 default environment.
639
640 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
641
642 When transferring memsize parameter to linux, some versions
643 expect it to be in bytes, others in MB.
644 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
645
646 CONFIG_OF_LIBFDT
647
648 New kernel versions are expecting firmware settings to be
649 passed using flattened device trees (based on open firmware
650 concepts).
651
652 CONFIG_OF_LIBFDT
653 * New libfdt-based support
654 * Adds the "fdt" command
655 * The bootm command automatically updates the fdt
656
657 OF_CPU - The proper name of the cpus node (only required for
658 MPC512X and MPC5xxx based boards).
659 OF_SOC - The proper name of the soc node (only required for
660 MPC512X and MPC5xxx based boards).
661 OF_TBCLK - The timebase frequency.
662 OF_STDOUT_PATH - The path to the console device
663
664 boards with QUICC Engines require OF_QE to set UCC MAC
665 addresses
666
667 CONFIG_OF_BOARD_SETUP
668
669 Board code has addition modification that it wants to make
670 to the flat device tree before handing it off to the kernel
671
672 CONFIG_OF_BOOT_CPU
673
674 This define fills in the correct boot CPU in the boot
675 param header, the default value is zero if undefined.
676
677 CONFIG_OF_IDE_FIXUP
678
679 U-Boot can detect if an IDE device is present or not.
680 If not, and this new config option is activated, U-Boot
681 removes the ATA node from the DTS before booting Linux,
682 so the Linux IDE driver does not probe the device and
683 crash. This is needed for buggy hardware (uc101) where
684 no pull down resistor is connected to the signal IDE5V_DD7.
685
686 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
687
688 This setting is mandatory for all boards that have only one
689 machine type and must be used to specify the machine type
690 number as it appears in the ARM machine registry
691 (see http://www.arm.linux.org.uk/developer/machines/).
692 Only boards that have multiple machine types supported
693 in a single configuration file and the machine type is
694 runtime discoverable, do not have to use this setting.
695
696 - vxWorks boot parameters:
697
698 bootvx constructs a valid bootline using the following
699 environments variables: bootfile, ipaddr, serverip, hostname.
700 It loads the vxWorks image pointed bootfile.
701
702 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
703 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
704 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
705 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
706
707 CONFIG_SYS_VXWORKS_ADD_PARAMS
708
709 Add it at the end of the bootline. E.g "u=username pw=secret"
710
711 Note: If a "bootargs" environment is defined, it will overwride
712 the defaults discussed just above.
713
714 - Cache Configuration:
715 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
716 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
717 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
718
719 - Cache Configuration for ARM:
720 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
721 controller
722 CONFIG_SYS_PL310_BASE - Physical base address of PL310
723 controller register space
724
725 - Serial Ports:
726 CONFIG_PL010_SERIAL
727
728 Define this if you want support for Amba PrimeCell PL010 UARTs.
729
730 CONFIG_PL011_SERIAL
731
732 Define this if you want support for Amba PrimeCell PL011 UARTs.
733
734 CONFIG_PL011_CLOCK
735
736 If you have Amba PrimeCell PL011 UARTs, set this variable to
737 the clock speed of the UARTs.
738
739 CONFIG_PL01x_PORTS
740
741 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
742 define this to a list of base addresses for each (supported)
743 port. See e.g. include/configs/versatile.h
744
745 CONFIG_PL011_SERIAL_RLCR
746
747 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
748 have separate receive and transmit line control registers. Set
749 this variable to initialize the extra register.
750
751 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
752
753 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
754 boot loader that has already initialized the UART. Define this
755 variable to flush the UART at init time.
756
757 CONFIG_SERIAL_HW_FLOW_CONTROL
758
759 Define this variable to enable hw flow control in serial driver.
760 Current user of this option is drivers/serial/nsl16550.c driver
761
762 - Console Interface:
763 Depending on board, define exactly one serial port
764 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
765 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
766 console by defining CONFIG_8xx_CONS_NONE
767
768 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
769 port routines must be defined elsewhere
770 (i.e. serial_init(), serial_getc(), ...)
771
772 CONFIG_CFB_CONSOLE
773 Enables console device for a color framebuffer. Needs following
774 defines (cf. smiLynxEM, i8042)
775 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
776 (default big endian)
777 VIDEO_HW_RECTFILL graphic chip supports
778 rectangle fill
779 (cf. smiLynxEM)
780 VIDEO_HW_BITBLT graphic chip supports
781 bit-blit (cf. smiLynxEM)
782 VIDEO_VISIBLE_COLS visible pixel columns
783 (cols=pitch)
784 VIDEO_VISIBLE_ROWS visible pixel rows
785 VIDEO_PIXEL_SIZE bytes per pixel
786 VIDEO_DATA_FORMAT graphic data format
787 (0-5, cf. cfb_console.c)
788 VIDEO_FB_ADRS framebuffer address
789 VIDEO_KBD_INIT_FCT keyboard int fct
790 (i.e. i8042_kbd_init())
791 VIDEO_TSTC_FCT test char fct
792 (i.e. i8042_tstc)
793 VIDEO_GETC_FCT get char fct
794 (i.e. i8042_getc)
795 CONFIG_CONSOLE_CURSOR cursor drawing on/off
796 (requires blink timer
797 cf. i8042.c)
798 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
799 CONFIG_CONSOLE_TIME display time/date info in
800 upper right corner
801 (requires CONFIG_CMD_DATE)
802 CONFIG_VIDEO_LOGO display Linux logo in
803 upper left corner
804 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
805 linux_logo.h for logo.
806 Requires CONFIG_VIDEO_LOGO
807 CONFIG_CONSOLE_EXTRA_INFO
808 additional board info beside
809 the logo
810
811 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
812 a limited number of ANSI escape sequences (cursor control,
813 erase functions and limited graphics rendition control).
814
815 When CONFIG_CFB_CONSOLE is defined, video console is
816 default i/o. Serial console can be forced with
817 environment 'console=serial'.
818
819 When CONFIG_SILENT_CONSOLE is defined, all console
820 messages (by U-Boot and Linux!) can be silenced with
821 the "silent" environment variable. See
822 doc/README.silent for more information.
823
824 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default
825 is 0x00.
826 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default
827 is 0xa0.
828
829 - Console Baudrate:
830 CONFIG_BAUDRATE - in bps
831 Select one of the baudrates listed in
832 CONFIG_SYS_BAUDRATE_TABLE, see below.
833 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
834
835 - Console Rx buffer length
836 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
837 the maximum receive buffer length for the SMC.
838 This option is actual only for 82xx and 8xx possible.
839 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
840 must be defined, to setup the maximum idle timeout for
841 the SMC.
842
843 - Pre-Console Buffer:
844 Prior to the console being initialised (i.e. serial UART
845 initialised etc) all console output is silently discarded.
846 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
847 buffer any console messages prior to the console being
848 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
849 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
850 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
851 bytes are output before the console is initialised, the
852 earlier bytes are discarded.
853
854 'Sane' compilers will generate smaller code if
855 CONFIG_PRE_CON_BUF_SZ is a power of 2
856
857 - Safe printf() functions
858 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
859 the printf() functions. These are defined in
860 include/vsprintf.h and include snprintf(), vsnprintf() and
861 so on. Code size increase is approximately 300-500 bytes.
862 If this option is not given then these functions will
863 silently discard their buffer size argument - this means
864 you are not getting any overflow checking in this case.
865
866 - Boot Delay: CONFIG_BOOTDELAY - in seconds
867 Delay before automatically booting the default image;
868 set to -1 to disable autoboot.
869 set to -2 to autoboot with no delay and not check for abort
870 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
871
872 See doc/README.autoboot for these options that
873 work with CONFIG_BOOTDELAY. None are required.
874 CONFIG_BOOT_RETRY_TIME
875 CONFIG_BOOT_RETRY_MIN
876 CONFIG_AUTOBOOT_KEYED
877 CONFIG_AUTOBOOT_PROMPT
878 CONFIG_AUTOBOOT_DELAY_STR
879 CONFIG_AUTOBOOT_STOP_STR
880 CONFIG_AUTOBOOT_DELAY_STR2
881 CONFIG_AUTOBOOT_STOP_STR2
882 CONFIG_ZERO_BOOTDELAY_CHECK
883 CONFIG_RESET_TO_RETRY
884
885 - Autoboot Command:
886 CONFIG_BOOTCOMMAND
887 Only needed when CONFIG_BOOTDELAY is enabled;
888 define a command string that is automatically executed
889 when no character is read on the console interface
890 within "Boot Delay" after reset.
891
892 CONFIG_BOOTARGS
893 This can be used to pass arguments to the bootm
894 command. The value of CONFIG_BOOTARGS goes into the
895 environment value "bootargs".
896
897 CONFIG_RAMBOOT and CONFIG_NFSBOOT
898 The value of these goes into the environment as
899 "ramboot" and "nfsboot" respectively, and can be used
900 as a convenience, when switching between booting from
901 RAM and NFS.
902
903 - Bootcount:
904 CONFIG_BOOTCOUNT_LIMIT
905 Implements a mechanism for detecting a repeating reboot
906 cycle, see:
907 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
908
909 CONFIG_BOOTCOUNT_ENV
910 If no softreset save registers are found on the hardware
911 "bootcount" is stored in the environment. To prevent a
912 saveenv on all reboots, the environment variable
913 "upgrade_available" is used. If "upgrade_available" is
914 0, "bootcount" is always 0, if "upgrade_available" is
915 1 "bootcount" is incremented in the environment.
916 So the Userspace Applikation must set the "upgrade_available"
917 and "bootcount" variable to 0, if a boot was successfully.
918
919 - Pre-Boot Commands:
920 CONFIG_PREBOOT
921
922 When this option is #defined, the existence of the
923 environment variable "preboot" will be checked
924 immediately before starting the CONFIG_BOOTDELAY
925 countdown and/or running the auto-boot command resp.
926 entering interactive mode.
927
928 This feature is especially useful when "preboot" is
929 automatically generated or modified. For an example
930 see the LWMON board specific code: here "preboot" is
931 modified when the user holds down a certain
932 combination of keys on the (special) keyboard when
933 booting the systems
934
935 - Serial Download Echo Mode:
936 CONFIG_LOADS_ECHO
937 If defined to 1, all characters received during a
938 serial download (using the "loads" command) are
939 echoed back. This might be needed by some terminal
940 emulations (like "cu"), but may as well just take
941 time on others. This setting #define's the initial
942 value of the "loads_echo" environment variable.
943
944 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
945 CONFIG_KGDB_BAUDRATE
946 Select one of the baudrates listed in
947 CONFIG_SYS_BAUDRATE_TABLE, see below.
948
949 - Monitor Functions:
950 Monitor commands can be included or excluded
951 from the build by using the #include files
952 <config_cmd_all.h> and #undef'ing unwanted
953 commands, or using <config_cmd_default.h>
954 and augmenting with additional #define's
955 for wanted commands.
956
957 The default command configuration includes all commands
958 except those marked below with a "*".
959
960 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
961 CONFIG_CMD_ASKENV * ask for env variable
962 CONFIG_CMD_BDI bdinfo
963 CONFIG_CMD_BEDBUG * Include BedBug Debugger
964 CONFIG_CMD_BMP * BMP support
965 CONFIG_CMD_BSP * Board specific commands
966 CONFIG_CMD_BOOTD bootd
967 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support
968 CONFIG_CMD_CACHE * icache, dcache
969 CONFIG_CMD_CLK * clock command support
970 CONFIG_CMD_CONSOLE coninfo
971 CONFIG_CMD_CRC32 * crc32
972 CONFIG_CMD_DATE * support for RTC, date/time...
973 CONFIG_CMD_DHCP * DHCP support
974 CONFIG_CMD_DIAG * Diagnostics
975 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
976 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
977 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
978 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
979 CONFIG_CMD_DTT * Digital Therm and Thermostat
980 CONFIG_CMD_ECHO echo arguments
981 CONFIG_CMD_EDITENV edit env variable
982 CONFIG_CMD_EEPROM * EEPROM read/write support
983 CONFIG_CMD_ELF * bootelf, bootvx
984 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
985 CONFIG_CMD_ENV_FLAGS * display details about env flags
986 CONFIG_CMD_ENV_EXISTS * check existence of env variable
987 CONFIG_CMD_EXPORTENV * export the environment
988 CONFIG_CMD_EXT2 * ext2 command support
989 CONFIG_CMD_EXT4 * ext4 command support
990 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
991 that work for multiple fs types
992 CONFIG_CMD_SAVEENV saveenv
993 CONFIG_CMD_FDC * Floppy Disk Support
994 CONFIG_CMD_FAT * FAT command support
995 CONFIG_CMD_FLASH flinfo, erase, protect
996 CONFIG_CMD_FPGA FPGA device initialization support
997 CONFIG_CMD_FUSE * Device fuse support
998 CONFIG_CMD_GETTIME * Get time since boot
999 CONFIG_CMD_GO * the 'go' command (exec code)
1000 CONFIG_CMD_GREPENV * search environment
1001 CONFIG_CMD_HASH * calculate hash / digest
1002 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
1003 CONFIG_CMD_I2C * I2C serial bus support
1004 CONFIG_CMD_IDE * IDE harddisk support
1005 CONFIG_CMD_IMI iminfo
1006 CONFIG_CMD_IMLS List all images found in NOR flash
1007 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
1008 CONFIG_CMD_IMMAP * IMMR dump support
1009 CONFIG_CMD_IOTRACE * I/O tracing for debugging
1010 CONFIG_CMD_IMPORTENV * import an environment
1011 CONFIG_CMD_INI * import data from an ini file into the env
1012 CONFIG_CMD_IRQ * irqinfo
1013 CONFIG_CMD_ITEST Integer/string test of 2 values
1014 CONFIG_CMD_JFFS2 * JFFS2 Support
1015 CONFIG_CMD_KGDB * kgdb
1016 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
1017 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
1018 (169.254.*.*)
1019 CONFIG_CMD_LOADB loadb
1020 CONFIG_CMD_LOADS loads
1021 CONFIG_CMD_MD5SUM * print md5 message digest
1022 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
1023 CONFIG_CMD_MEMINFO * Display detailed memory information
1024 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
1025 loop, loopw
1026 CONFIG_CMD_MEMTEST * mtest
1027 CONFIG_CMD_MISC Misc functions like sleep etc
1028 CONFIG_CMD_MMC * MMC memory mapped support
1029 CONFIG_CMD_MII * MII utility commands
1030 CONFIG_CMD_MTDPARTS * MTD partition support
1031 CONFIG_CMD_NAND * NAND support
1032 CONFIG_CMD_NET bootp, tftpboot, rarpboot
1033 CONFIG_CMD_NFS NFS support
1034 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
1035 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
1036 CONFIG_CMD_PCI * pciinfo
1037 CONFIG_CMD_PCMCIA * PCMCIA support
1038 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
1039 host
1040 CONFIG_CMD_PORTIO * Port I/O
1041 CONFIG_CMD_READ * Read raw data from partition
1042 CONFIG_CMD_REGINFO * Register dump
1043 CONFIG_CMD_RUN run command in env variable
1044 CONFIG_CMD_SANDBOX * sb command to access sandbox features
1045 CONFIG_CMD_SAVES * save S record dump
1046 CONFIG_CMD_SCSI * SCSI Support
1047 CONFIG_CMD_SDRAM * print SDRAM configuration information
1048 (requires CONFIG_CMD_I2C)
1049 CONFIG_CMD_SETGETDCR Support for DCR Register access
1050 (4xx only)
1051 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
1052 CONFIG_CMD_SHA1SUM * print sha1 memory digest
1053 (requires CONFIG_CMD_MEMORY)
1054 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
1055 CONFIG_CMD_SOURCE "source" command Support
1056 CONFIG_CMD_SPI * SPI serial bus support
1057 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
1058 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
1059 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
1060 CONFIG_CMD_TIMER * access to the system tick timer
1061 CONFIG_CMD_USB * USB support
1062 CONFIG_CMD_CDP * Cisco Discover Protocol support
1063 CONFIG_CMD_MFSL * Microblaze FSL support
1064 CONFIG_CMD_XIMG Load part of Multi Image
1065 CONFIG_CMD_UUID * Generate random UUID or GUID string
1066
1067 EXAMPLE: If you want all functions except of network
1068 support you can write:
1069
1070 #include "config_cmd_all.h"
1071 #undef CONFIG_CMD_NET
1072
1073 Other Commands:
1074 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
1075
1076 Note: Don't enable the "icache" and "dcache" commands
1077 (configuration option CONFIG_CMD_CACHE) unless you know
1078 what you (and your U-Boot users) are doing. Data
1079 cache cannot be enabled on systems like the 8xx or
1080 8260 (where accesses to the IMMR region must be
1081 uncached), and it cannot be disabled on all other
1082 systems where we (mis-) use the data cache to hold an
1083 initial stack and some data.
1084
1085
1086 XXX - this list needs to get updated!
1087
1088 - Regular expression support:
1089 CONFIG_REGEX
1090 If this variable is defined, U-Boot is linked against
1091 the SLRE (Super Light Regular Expression) library,
1092 which adds regex support to some commands, as for
1093 example "env grep" and "setexpr".
1094
1095 - Device tree:
1096 CONFIG_OF_CONTROL
1097 If this variable is defined, U-Boot will use a device tree
1098 to configure its devices, instead of relying on statically
1099 compiled #defines in the board file. This option is
1100 experimental and only available on a few boards. The device
1101 tree is available in the global data as gd->fdt_blob.
1102
1103 U-Boot needs to get its device tree from somewhere. This can
1104 be done using one of the two options below:
1105
1106 CONFIG_OF_EMBED
1107 If this variable is defined, U-Boot will embed a device tree
1108 binary in its image. This device tree file should be in the
1109 board directory and called <soc>-<board>.dts. The binary file
1110 is then picked up in board_init_f() and made available through
1111 the global data structure as gd->blob.
1112
1113 CONFIG_OF_SEPARATE
1114 If this variable is defined, U-Boot will build a device tree
1115 binary. It will be called u-boot.dtb. Architecture-specific
1116 code will locate it at run-time. Generally this works by:
1117
1118 cat u-boot.bin u-boot.dtb >image.bin
1119
1120 and in fact, U-Boot does this for you, creating a file called
1121 u-boot-dtb.bin which is useful in the common case. You can
1122 still use the individual files if you need something more
1123 exotic.
1124
1125 - Watchdog:
1126 CONFIG_WATCHDOG
1127 If this variable is defined, it enables watchdog
1128 support for the SoC. There must be support in the SoC
1129 specific code for a watchdog. For the 8xx and 8260
1130 CPUs, the SIU Watchdog feature is enabled in the SYPCR
1131 register. When supported for a specific SoC is
1132 available, then no further board specific code should
1133 be needed to use it.
1134
1135 CONFIG_HW_WATCHDOG
1136 When using a watchdog circuitry external to the used
1137 SoC, then define this variable and provide board
1138 specific code for the "hw_watchdog_reset" function.
1139
1140 - U-Boot Version:
1141 CONFIG_VERSION_VARIABLE
1142 If this variable is defined, an environment variable
1143 named "ver" is created by U-Boot showing the U-Boot
1144 version as printed by the "version" command.
1145 Any change to this variable will be reverted at the
1146 next reset.
1147
1148 - Real-Time Clock:
1149
1150 When CONFIG_CMD_DATE is selected, the type of the RTC
1151 has to be selected, too. Define exactly one of the
1152 following options:
1153
1154 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1155 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1156 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1157 CONFIG_RTC_MC146818 - use MC146818 RTC
1158 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1159 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1160 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1161 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
1162 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1163 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1164 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1165 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1166 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1167 RV3029 RTC.
1168
1169 Note that if the RTC uses I2C, then the I2C interface
1170 must also be configured. See I2C Support, below.
1171
1172 - GPIO Support:
1173 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1174
1175 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1176 chip-ngpio pairs that tell the PCA953X driver the number of
1177 pins supported by a particular chip.
1178
1179 Note that if the GPIO device uses I2C, then the I2C interface
1180 must also be configured. See I2C Support, below.
1181
1182 - I/O tracing:
1183 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
1184 accesses and can checksum them or write a list of them out
1185 to memory. See the 'iotrace' command for details. This is
1186 useful for testing device drivers since it can confirm that
1187 the driver behaves the same way before and after a code
1188 change. Currently this is supported on sandbox and arm. To
1189 add support for your architecture, add '#include <iotrace.h>'
1190 to the bottom of arch/<arch>/include/asm/io.h and test.
1191
1192 Example output from the 'iotrace stats' command is below.
1193 Note that if the trace buffer is exhausted, the checksum will
1194 still continue to operate.
1195
1196 iotrace is enabled
1197 Start: 10000000 (buffer start address)
1198 Size: 00010000 (buffer size)
1199 Offset: 00000120 (current buffer offset)
1200 Output: 10000120 (start + offset)
1201 Count: 00000018 (number of trace records)
1202 CRC32: 9526fb66 (CRC32 of all trace records)
1203
1204 - Timestamp Support:
1205
1206 When CONFIG_TIMESTAMP is selected, the timestamp
1207 (date and time) of an image is printed by image
1208 commands like bootm or iminfo. This option is
1209 automatically enabled when you select CONFIG_CMD_DATE .
1210
1211 - Partition Labels (disklabels) Supported:
1212 Zero or more of the following:
1213 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1214 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1215 Intel architecture, USB sticks, etc.
1216 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1217 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1218 bootloader. Note 2TB partition limit; see
1219 disk/part_efi.c
1220 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1221
1222 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1223 CONFIG_CMD_SCSI) you must configure support for at
1224 least one non-MTD partition type as well.
1225
1226 - IDE Reset method:
1227 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1228 board configurations files but used nowhere!
1229
1230 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1231 be performed by calling the function
1232 ide_set_reset(int reset)
1233 which has to be defined in a board specific file
1234
1235 - ATAPI Support:
1236 CONFIG_ATAPI
1237
1238 Set this to enable ATAPI support.
1239
1240 - LBA48 Support
1241 CONFIG_LBA48
1242
1243 Set this to enable support for disks larger than 137GB
1244 Also look at CONFIG_SYS_64BIT_LBA.
1245 Whithout these , LBA48 support uses 32bit variables and will 'only'
1246 support disks up to 2.1TB.
1247
1248 CONFIG_SYS_64BIT_LBA:
1249 When enabled, makes the IDE subsystem use 64bit sector addresses.
1250 Default is 32bit.
1251
1252 - SCSI Support:
1253 At the moment only there is only support for the
1254 SYM53C8XX SCSI controller; define
1255 CONFIG_SCSI_SYM53C8XX to enable it.
1256
1257 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1258 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1259 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1260 maximum numbers of LUNs, SCSI ID's and target
1261 devices.
1262 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1263
1264 The environment variable 'scsidevs' is set to the number of
1265 SCSI devices found during the last scan.
1266
1267 - NETWORK Support (PCI):
1268 CONFIG_E1000
1269 Support for Intel 8254x/8257x gigabit chips.
1270
1271 CONFIG_E1000_SPI
1272 Utility code for direct access to the SPI bus on Intel 8257x.
1273 This does not do anything useful unless you set at least one
1274 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1275
1276 CONFIG_E1000_SPI_GENERIC
1277 Allow generic access to the SPI bus on the Intel 8257x, for
1278 example with the "sspi" command.
1279
1280 CONFIG_CMD_E1000
1281 Management command for E1000 devices. When used on devices
1282 with SPI support you can reprogram the EEPROM from U-Boot.
1283
1284 CONFIG_E1000_FALLBACK_MAC
1285 default MAC for empty EEPROM after production.
1286
1287 CONFIG_EEPRO100
1288 Support for Intel 82557/82559/82559ER chips.
1289 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1290 write routine for first time initialisation.
1291
1292 CONFIG_TULIP
1293 Support for Digital 2114x chips.
1294 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1295 modem chip initialisation (KS8761/QS6611).
1296
1297 CONFIG_NATSEMI
1298 Support for National dp83815 chips.
1299
1300 CONFIG_NS8382X
1301 Support for National dp8382[01] gigabit chips.
1302
1303 - NETWORK Support (other):
1304
1305 CONFIG_DRIVER_AT91EMAC
1306 Support for AT91RM9200 EMAC.
1307
1308 CONFIG_RMII
1309 Define this to use reduced MII inteface
1310
1311 CONFIG_DRIVER_AT91EMAC_QUIET
1312 If this defined, the driver is quiet.
1313 The driver doen't show link status messages.
1314
1315 CONFIG_CALXEDA_XGMAC
1316 Support for the Calxeda XGMAC device
1317
1318 CONFIG_LAN91C96
1319 Support for SMSC's LAN91C96 chips.
1320
1321 CONFIG_LAN91C96_BASE
1322 Define this to hold the physical address
1323 of the LAN91C96's I/O space
1324
1325 CONFIG_LAN91C96_USE_32_BIT
1326 Define this to enable 32 bit addressing
1327
1328 CONFIG_SMC91111
1329 Support for SMSC's LAN91C111 chip
1330
1331 CONFIG_SMC91111_BASE
1332 Define this to hold the physical address
1333 of the device (I/O space)
1334
1335 CONFIG_SMC_USE_32_BIT
1336 Define this if data bus is 32 bits
1337
1338 CONFIG_SMC_USE_IOFUNCS
1339 Define this to use i/o functions instead of macros
1340 (some hardware wont work with macros)
1341
1342 CONFIG_DRIVER_TI_EMAC
1343 Support for davinci emac
1344
1345 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1346 Define this if you have more then 3 PHYs.
1347
1348 CONFIG_FTGMAC100
1349 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1350
1351 CONFIG_FTGMAC100_EGIGA
1352 Define this to use GE link update with gigabit PHY.
1353 Define this if FTGMAC100 is connected to gigabit PHY.
1354 If your system has 10/100 PHY only, it might not occur
1355 wrong behavior. Because PHY usually return timeout or
1356 useless data when polling gigabit status and gigabit
1357 control registers. This behavior won't affect the
1358 correctnessof 10/100 link speed update.
1359
1360 CONFIG_SMC911X
1361 Support for SMSC's LAN911x and LAN921x chips
1362
1363 CONFIG_SMC911X_BASE
1364 Define this to hold the physical address
1365 of the device (I/O space)
1366
1367 CONFIG_SMC911X_32_BIT
1368 Define this if data bus is 32 bits
1369
1370 CONFIG_SMC911X_16_BIT
1371 Define this if data bus is 16 bits. If your processor
1372 automatically converts one 32 bit word to two 16 bit
1373 words you may also try CONFIG_SMC911X_32_BIT.
1374
1375 CONFIG_SH_ETHER
1376 Support for Renesas on-chip Ethernet controller
1377
1378 CONFIG_SH_ETHER_USE_PORT
1379 Define the number of ports to be used
1380
1381 CONFIG_SH_ETHER_PHY_ADDR
1382 Define the ETH PHY's address
1383
1384 CONFIG_SH_ETHER_CACHE_WRITEBACK
1385 If this option is set, the driver enables cache flush.
1386
1387 - PWM Support:
1388 CONFIG_PWM_IMX
1389 Support for PWM modul on the imx6.
1390
1391 - TPM Support:
1392 CONFIG_TPM
1393 Support TPM devices.
1394
1395 CONFIG_TPM_TIS_I2C
1396 Support for i2c bus TPM devices. Only one device
1397 per system is supported at this time.
1398
1399 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1400 Define the the i2c bus number for the TPM device
1401
1402 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1403 Define the TPM's address on the i2c bus
1404
1405 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1406 Define the burst count bytes upper limit
1407
1408 CONFIG_TPM_ATMEL_TWI
1409 Support for Atmel TWI TPM device. Requires I2C support.
1410
1411 CONFIG_TPM_TIS_LPC
1412 Support for generic parallel port TPM devices. Only one device
1413 per system is supported at this time.
1414
1415 CONFIG_TPM_TIS_BASE_ADDRESS
1416 Base address where the generic TPM device is mapped
1417 to. Contemporary x86 systems usually map it at
1418 0xfed40000.
1419
1420 CONFIG_CMD_TPM
1421 Add tpm monitor functions.
1422 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1423 provides monitor access to authorized functions.
1424
1425 CONFIG_TPM
1426 Define this to enable the TPM support library which provides
1427 functional interfaces to some TPM commands.
1428 Requires support for a TPM device.
1429
1430 CONFIG_TPM_AUTH_SESSIONS
1431 Define this to enable authorized functions in the TPM library.
1432 Requires CONFIG_TPM and CONFIG_SHA1.
1433
1434 - USB Support:
1435 At the moment only the UHCI host controller is
1436 supported (PIP405, MIP405, MPC5200); define
1437 CONFIG_USB_UHCI to enable it.
1438 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1439 and define CONFIG_USB_STORAGE to enable the USB
1440 storage devices.
1441 Note:
1442 Supported are USB Keyboards and USB Floppy drives
1443 (TEAC FD-05PUB).
1444 MPC5200 USB requires additional defines:
1445 CONFIG_USB_CLOCK
1446 for 528 MHz Clock: 0x0001bbbb
1447 CONFIG_PSC3_USB
1448 for USB on PSC3
1449 CONFIG_USB_CONFIG
1450 for differential drivers: 0x00001000
1451 for single ended drivers: 0x00005000
1452 for differential drivers on PSC3: 0x00000100
1453 for single ended drivers on PSC3: 0x00004100
1454 CONFIG_SYS_USB_EVENT_POLL
1455 May be defined to allow interrupt polling
1456 instead of using asynchronous interrupts
1457
1458 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1459 txfilltuning field in the EHCI controller on reset.
1460
1461 - USB Device:
1462 Define the below if you wish to use the USB console.
1463 Once firmware is rebuilt from a serial console issue the
1464 command "setenv stdin usbtty; setenv stdout usbtty" and
1465 attach your USB cable. The Unix command "dmesg" should print
1466 it has found a new device. The environment variable usbtty
1467 can be set to gserial or cdc_acm to enable your device to
1468 appear to a USB host as a Linux gserial device or a
1469 Common Device Class Abstract Control Model serial device.
1470 If you select usbtty = gserial you should be able to enumerate
1471 a Linux host by
1472 # modprobe usbserial vendor=0xVendorID product=0xProductID
1473 else if using cdc_acm, simply setting the environment
1474 variable usbtty to be cdc_acm should suffice. The following
1475 might be defined in YourBoardName.h
1476
1477 CONFIG_USB_DEVICE
1478 Define this to build a UDC device
1479
1480 CONFIG_USB_TTY
1481 Define this to have a tty type of device available to
1482 talk to the UDC device
1483
1484 CONFIG_USBD_HS
1485 Define this to enable the high speed support for usb
1486 device and usbtty. If this feature is enabled, a routine
1487 int is_usbd_high_speed(void)
1488 also needs to be defined by the driver to dynamically poll
1489 whether the enumeration has succeded at high speed or full
1490 speed.
1491
1492 CONFIG_SYS_CONSOLE_IS_IN_ENV
1493 Define this if you want stdin, stdout &/or stderr to
1494 be set to usbtty.
1495
1496 mpc8xx:
1497 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1498 Derive USB clock from external clock "blah"
1499 - CONFIG_SYS_USB_EXTC_CLK 0x02
1500
1501 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1502 Derive USB clock from brgclk
1503 - CONFIG_SYS_USB_BRG_CLK 0x04
1504
1505 If you have a USB-IF assigned VendorID then you may wish to
1506 define your own vendor specific values either in BoardName.h
1507 or directly in usbd_vendor_info.h. If you don't define
1508 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1509 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1510 should pretend to be a Linux device to it's target host.
1511
1512 CONFIG_USBD_MANUFACTURER
1513 Define this string as the name of your company for
1514 - CONFIG_USBD_MANUFACTURER "my company"
1515
1516 CONFIG_USBD_PRODUCT_NAME
1517 Define this string as the name of your product
1518 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1519
1520 CONFIG_USBD_VENDORID
1521 Define this as your assigned Vendor ID from the USB
1522 Implementors Forum. This *must* be a genuine Vendor ID
1523 to avoid polluting the USB namespace.
1524 - CONFIG_USBD_VENDORID 0xFFFF
1525
1526 CONFIG_USBD_PRODUCTID
1527 Define this as the unique Product ID
1528 for your device
1529 - CONFIG_USBD_PRODUCTID 0xFFFF
1530
1531 - ULPI Layer Support:
1532 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1533 the generic ULPI layer. The generic layer accesses the ULPI PHY
1534 via the platform viewport, so you need both the genric layer and
1535 the viewport enabled. Currently only Chipidea/ARC based
1536 viewport is supported.
1537 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1538 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1539 If your ULPI phy needs a different reference clock than the
1540 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1541 the appropriate value in Hz.
1542
1543 - MMC Support:
1544 The MMC controller on the Intel PXA is supported. To
1545 enable this define CONFIG_MMC. The MMC can be
1546 accessed from the boot prompt by mapping the device
1547 to physical memory similar to flash. Command line is
1548 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1549 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1550
1551 CONFIG_SH_MMCIF
1552 Support for Renesas on-chip MMCIF controller
1553
1554 CONFIG_SH_MMCIF_ADDR
1555 Define the base address of MMCIF registers
1556
1557 CONFIG_SH_MMCIF_CLK
1558 Define the clock frequency for MMCIF
1559
1560 CONFIG_GENERIC_MMC
1561 Enable the generic MMC driver
1562
1563 CONFIG_SUPPORT_EMMC_BOOT
1564 Enable some additional features of the eMMC boot partitions.
1565
1566 CONFIG_SUPPORT_EMMC_RPMB
1567 Enable the commands for reading, writing and programming the
1568 key for the Replay Protection Memory Block partition in eMMC.
1569
1570 - USB Device Firmware Update (DFU) class support:
1571 CONFIG_DFU_FUNCTION
1572 This enables the USB portion of the DFU USB class
1573
1574 CONFIG_CMD_DFU
1575 This enables the command "dfu" which is used to have
1576 U-Boot create a DFU class device via USB. This command
1577 requires that the "dfu_alt_info" environment variable be
1578 set and define the alt settings to expose to the host.
1579
1580 CONFIG_DFU_MMC
1581 This enables support for exposing (e)MMC devices via DFU.
1582
1583 CONFIG_DFU_NAND
1584 This enables support for exposing NAND devices via DFU.
1585
1586 CONFIG_DFU_RAM
1587 This enables support for exposing RAM via DFU.
1588 Note: DFU spec refer to non-volatile memory usage, but
1589 allow usages beyond the scope of spec - here RAM usage,
1590 one that would help mostly the developer.
1591
1592 CONFIG_SYS_DFU_DATA_BUF_SIZE
1593 Dfu transfer uses a buffer before writing data to the
1594 raw storage device. Make the size (in bytes) of this buffer
1595 configurable. The size of this buffer is also configurable
1596 through the "dfu_bufsiz" environment variable.
1597
1598 CONFIG_SYS_DFU_MAX_FILE_SIZE
1599 When updating files rather than the raw storage device,
1600 we use a static buffer to copy the file into and then write
1601 the buffer once we've been given the whole file. Define
1602 this to the maximum filesize (in bytes) for the buffer.
1603 Default is 4 MiB if undefined.
1604
1605 DFU_DEFAULT_POLL_TIMEOUT
1606 Poll timeout [ms], is the timeout a device can send to the
1607 host. The host must wait for this timeout before sending
1608 a subsequent DFU_GET_STATUS request to the device.
1609
1610 DFU_MANIFEST_POLL_TIMEOUT
1611 Poll timeout [ms], which the device sends to the host when
1612 entering dfuMANIFEST state. Host waits this timeout, before
1613 sending again an USB request to the device.
1614
1615 - USB Device Android Fastboot support:
1616 CONFIG_CMD_FASTBOOT
1617 This enables the command "fastboot" which enables the Android
1618 fastboot mode for the platform's USB device. Fastboot is a USB
1619 protocol for downloading images, flashing and device control
1620 used on Android devices.
1621 See doc/README.android-fastboot for more information.
1622
1623 CONFIG_ANDROID_BOOT_IMAGE
1624 This enables support for booting images which use the Android
1625 image format header.
1626
1627 CONFIG_USB_FASTBOOT_BUF_ADDR
1628 The fastboot protocol requires a large memory buffer for
1629 downloads. Define this to the starting RAM address to use for
1630 downloaded images.
1631
1632 CONFIG_USB_FASTBOOT_BUF_SIZE
1633 The fastboot protocol requires a large memory buffer for
1634 downloads. This buffer should be as large as possible for a
1635 platform. Define this to the size available RAM for fastboot.
1636
1637 CONFIG_FASTBOOT_FLASH
1638 The fastboot protocol includes a "flash" command for writing
1639 the downloaded image to a non-volatile storage device. Define
1640 this to enable the "fastboot flash" command.
1641
1642 CONFIG_FASTBOOT_FLASH_MMC_DEV
1643 The fastboot "flash" command requires additional information
1644 regarding the non-volatile storage device. Define this to
1645 the eMMC device that fastboot should use to store the image.
1646
1647 - Journaling Flash filesystem support:
1648 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1649 CONFIG_JFFS2_NAND_DEV
1650 Define these for a default partition on a NAND device
1651
1652 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1653 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1654 Define these for a default partition on a NOR device
1655
1656 CONFIG_SYS_JFFS_CUSTOM_PART
1657 Define this to create an own partition. You have to provide a
1658 function struct part_info* jffs2_part_info(int part_num)
1659
1660 If you define only one JFFS2 partition you may also want to
1661 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1662 to disable the command chpart. This is the default when you
1663 have not defined a custom partition
1664
1665 - FAT(File Allocation Table) filesystem write function support:
1666 CONFIG_FAT_WRITE
1667
1668 Define this to enable support for saving memory data as a
1669 file in FAT formatted partition.
1670
1671 This will also enable the command "fatwrite" enabling the
1672 user to write files to FAT.
1673
1674 CBFS (Coreboot Filesystem) support
1675 CONFIG_CMD_CBFS
1676
1677 Define this to enable support for reading from a Coreboot
1678 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1679 and cbfsload.
1680
1681 - FAT(File Allocation Table) filesystem cluster size:
1682 CONFIG_FS_FAT_MAX_CLUSTSIZE
1683
1684 Define the max cluster size for fat operations else
1685 a default value of 65536 will be defined.
1686
1687 - Keyboard Support:
1688 CONFIG_ISA_KEYBOARD
1689
1690 Define this to enable standard (PC-Style) keyboard
1691 support
1692
1693 CONFIG_I8042_KBD
1694 Standard PC keyboard driver with US (is default) and
1695 GERMAN key layout (switch via environment 'keymap=de') support.
1696 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1697 for cfb_console. Supports cursor blinking.
1698
1699 CONFIG_CROS_EC_KEYB
1700 Enables a Chrome OS keyboard using the CROS_EC interface.
1701 This uses CROS_EC to communicate with a second microcontroller
1702 which provides key scans on request.
1703
1704 - Video support:
1705 CONFIG_VIDEO
1706
1707 Define this to enable video support (for output to
1708 video).
1709
1710 CONFIG_VIDEO_CT69000
1711
1712 Enable Chips & Technologies 69000 Video chip
1713
1714 CONFIG_VIDEO_SMI_LYNXEM
1715 Enable Silicon Motion SMI 712/710/810 Video chip. The
1716 video output is selected via environment 'videoout'
1717 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1718 assumed.
1719
1720 For the CT69000 and SMI_LYNXEM drivers, videomode is
1721 selected via environment 'videomode'. Two different ways
1722 are possible:
1723 - "videomode=num" 'num' is a standard LiLo mode numbers.
1724 Following standard modes are supported (* is default):
1725
1726 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1727 -------------+---------------------------------------------
1728 8 bits | 0x301* 0x303 0x305 0x161 0x307
1729 15 bits | 0x310 0x313 0x316 0x162 0x319
1730 16 bits | 0x311 0x314 0x317 0x163 0x31A
1731 24 bits | 0x312 0x315 0x318 ? 0x31B
1732 -------------+---------------------------------------------
1733 (i.e. setenv videomode 317; saveenv; reset;)
1734
1735 - "videomode=bootargs" all the video parameters are parsed
1736 from the bootargs. (See drivers/video/videomodes.c)
1737
1738
1739 CONFIG_VIDEO_SED13806
1740 Enable Epson SED13806 driver. This driver supports 8bpp
1741 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1742 or CONFIG_VIDEO_SED13806_16BPP
1743
1744 CONFIG_FSL_DIU_FB
1745 Enable the Freescale DIU video driver. Reference boards for
1746 SOCs that have a DIU should define this macro to enable DIU
1747 support, and should also define these other macros:
1748
1749 CONFIG_SYS_DIU_ADDR
1750 CONFIG_VIDEO
1751 CONFIG_CMD_BMP
1752 CONFIG_CFB_CONSOLE
1753 CONFIG_VIDEO_SW_CURSOR
1754 CONFIG_VGA_AS_SINGLE_DEVICE
1755 CONFIG_VIDEO_LOGO
1756 CONFIG_VIDEO_BMP_LOGO
1757
1758 The DIU driver will look for the 'video-mode' environment
1759 variable, and if defined, enable the DIU as a console during
1760 boot. See the documentation file README.video for a
1761 description of this variable.
1762
1763 CONFIG_VIDEO_VGA
1764
1765 Enable the VGA video / BIOS for x86. The alternative if you
1766 are using coreboot is to use the coreboot frame buffer
1767 driver.
1768
1769
1770 - Keyboard Support:
1771 CONFIG_KEYBOARD
1772
1773 Define this to enable a custom keyboard support.
1774 This simply calls drv_keyboard_init() which must be
1775 defined in your board-specific files.
1776 The only board using this so far is RBC823.
1777
1778 - LCD Support: CONFIG_LCD
1779
1780 Define this to enable LCD support (for output to LCD
1781 display); also select one of the supported displays
1782 by defining one of these:
1783
1784 CONFIG_ATMEL_LCD:
1785
1786 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1787
1788 CONFIG_NEC_NL6448AC33:
1789
1790 NEC NL6448AC33-18. Active, color, single scan.
1791
1792 CONFIG_NEC_NL6448BC20
1793
1794 NEC NL6448BC20-08. 6.5", 640x480.
1795 Active, color, single scan.
1796
1797 CONFIG_NEC_NL6448BC33_54
1798
1799 NEC NL6448BC33-54. 10.4", 640x480.
1800 Active, color, single scan.
1801
1802 CONFIG_SHARP_16x9
1803
1804 Sharp 320x240. Active, color, single scan.
1805 It isn't 16x9, and I am not sure what it is.
1806
1807 CONFIG_SHARP_LQ64D341
1808
1809 Sharp LQ64D341 display, 640x480.
1810 Active, color, single scan.
1811
1812 CONFIG_HLD1045
1813
1814 HLD1045 display, 640x480.
1815 Active, color, single scan.
1816
1817 CONFIG_OPTREX_BW
1818
1819 Optrex CBL50840-2 NF-FW 99 22 M5
1820 or
1821 Hitachi LMG6912RPFC-00T
1822 or
1823 Hitachi SP14Q002
1824
1825 320x240. Black & white.
1826
1827 Normally display is black on white background; define
1828 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1829
1830 CONFIG_LCD_ALIGNMENT
1831
1832 Normally the LCD is page-aligned (tyically 4KB). If this is
1833 defined then the LCD will be aligned to this value instead.
1834 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1835 here, since it is cheaper to change data cache settings on
1836 a per-section basis.
1837
1838 CONFIG_CONSOLE_SCROLL_LINES
1839
1840 When the console need to be scrolled, this is the number of
1841 lines to scroll by. It defaults to 1. Increasing this makes
1842 the console jump but can help speed up operation when scrolling
1843 is slow.
1844
1845 CONFIG_LCD_BMP_RLE8
1846
1847 Support drawing of RLE8-compressed bitmaps on the LCD.
1848
1849 CONFIG_I2C_EDID
1850
1851 Enables an 'i2c edid' command which can read EDID
1852 information over I2C from an attached LCD display.
1853
1854 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1855
1856 If this option is set, the environment is checked for
1857 a variable "splashimage". If found, the usual display
1858 of logo, copyright and system information on the LCD
1859 is suppressed and the BMP image at the address
1860 specified in "splashimage" is loaded instead. The
1861 console is redirected to the "nulldev", too. This
1862 allows for a "silent" boot where a splash screen is
1863 loaded very quickly after power-on.
1864
1865 CONFIG_SPLASHIMAGE_GUARD
1866
1867 If this option is set, then U-Boot will prevent the environment
1868 variable "splashimage" from being set to a problematic address
1869 (see README.displaying-bmps).
1870 This option is useful for targets where, due to alignment
1871 restrictions, an improperly aligned BMP image will cause a data
1872 abort. If you think you will not have problems with unaligned
1873 accesses (for example because your toolchain prevents them)
1874 there is no need to set this option.
1875
1876 CONFIG_SPLASH_SCREEN_ALIGN
1877
1878 If this option is set the splash image can be freely positioned
1879 on the screen. Environment variable "splashpos" specifies the
1880 position as "x,y". If a positive number is given it is used as
1881 number of pixel from left/top. If a negative number is given it
1882 is used as number of pixel from right/bottom. You can also
1883 specify 'm' for centering the image.
1884
1885 Example:
1886 setenv splashpos m,m
1887 => image at center of screen
1888
1889 setenv splashpos 30,20
1890 => image at x = 30 and y = 20
1891
1892 setenv splashpos -10,m
1893 => vertically centered image
1894 at x = dspWidth - bmpWidth - 9
1895
1896 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1897
1898 If this option is set, additionally to standard BMP
1899 images, gzipped BMP images can be displayed via the
1900 splashscreen support or the bmp command.
1901
1902 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1903
1904 If this option is set, 8-bit RLE compressed BMP images
1905 can be displayed via the splashscreen support or the
1906 bmp command.
1907
1908 - Do compresssing for memory range:
1909 CONFIG_CMD_ZIP
1910
1911 If this option is set, it would use zlib deflate method
1912 to compress the specified memory at its best effort.
1913
1914 - Compression support:
1915 CONFIG_GZIP
1916
1917 Enabled by default to support gzip compressed images.
1918
1919 CONFIG_BZIP2
1920
1921 If this option is set, support for bzip2 compressed
1922 images is included. If not, only uncompressed and gzip
1923 compressed images are supported.
1924
1925 NOTE: the bzip2 algorithm requires a lot of RAM, so
1926 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1927 be at least 4MB.
1928
1929 CONFIG_LZMA
1930
1931 If this option is set, support for lzma compressed
1932 images is included.
1933
1934 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1935 requires an amount of dynamic memory that is given by the
1936 formula:
1937
1938 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1939
1940 Where lc and lp stand for, respectively, Literal context bits
1941 and Literal pos bits.
1942
1943 This value is upper-bounded by 14MB in the worst case. Anyway,
1944 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1945 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1946 a very small buffer.
1947
1948 Use the lzmainfo tool to determinate the lc and lp values and
1949 then calculate the amount of needed dynamic memory (ensuring
1950 the appropriate CONFIG_SYS_MALLOC_LEN value).
1951
1952 CONFIG_LZO
1953
1954 If this option is set, support for LZO compressed images
1955 is included.
1956
1957 - MII/PHY support:
1958 CONFIG_PHY_ADDR
1959
1960 The address of PHY on MII bus.
1961
1962 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1963
1964 The clock frequency of the MII bus
1965
1966 CONFIG_PHY_GIGE
1967
1968 If this option is set, support for speed/duplex
1969 detection of gigabit PHY is included.
1970
1971 CONFIG_PHY_RESET_DELAY
1972
1973 Some PHY like Intel LXT971A need extra delay after
1974 reset before any MII register access is possible.
1975 For such PHY, set this option to the usec delay
1976 required. (minimum 300usec for LXT971A)
1977
1978 CONFIG_PHY_CMD_DELAY (ppc4xx)
1979
1980 Some PHY like Intel LXT971A need extra delay after
1981 command issued before MII status register can be read
1982
1983 - Ethernet address:
1984 CONFIG_ETHADDR
1985 CONFIG_ETH1ADDR
1986 CONFIG_ETH2ADDR
1987 CONFIG_ETH3ADDR
1988 CONFIG_ETH4ADDR
1989 CONFIG_ETH5ADDR
1990
1991 Define a default value for Ethernet address to use
1992 for the respective Ethernet interface, in case this
1993 is not determined automatically.
1994
1995 - IP address:
1996 CONFIG_IPADDR
1997
1998 Define a default value for the IP address to use for
1999 the default Ethernet interface, in case this is not
2000 determined through e.g. bootp.
2001 (Environment variable "ipaddr")
2002
2003 - Server IP address:
2004 CONFIG_SERVERIP
2005
2006 Defines a default value for the IP address of a TFTP
2007 server to contact when using the "tftboot" command.
2008 (Environment variable "serverip")
2009
2010 CONFIG_KEEP_SERVERADDR
2011
2012 Keeps the server's MAC address, in the env 'serveraddr'
2013 for passing to bootargs (like Linux's netconsole option)
2014
2015 - Gateway IP address:
2016 CONFIG_GATEWAYIP
2017
2018 Defines a default value for the IP address of the
2019 default router where packets to other networks are
2020 sent to.
2021 (Environment variable "gatewayip")
2022
2023 - Subnet mask:
2024 CONFIG_NETMASK
2025
2026 Defines a default value for the subnet mask (or
2027 routing prefix) which is used to determine if an IP
2028 address belongs to the local subnet or needs to be
2029 forwarded through a router.
2030 (Environment variable "netmask")
2031
2032 - Multicast TFTP Mode:
2033 CONFIG_MCAST_TFTP
2034
2035 Defines whether you want to support multicast TFTP as per
2036 rfc-2090; for example to work with atftp. Lets lots of targets
2037 tftp down the same boot image concurrently. Note: the Ethernet
2038 driver in use must provide a function: mcast() to join/leave a
2039 multicast group.
2040
2041 - BOOTP Recovery Mode:
2042 CONFIG_BOOTP_RANDOM_DELAY
2043
2044 If you have many targets in a network that try to
2045 boot using BOOTP, you may want to avoid that all
2046 systems send out BOOTP requests at precisely the same
2047 moment (which would happen for instance at recovery
2048 from a power failure, when all systems will try to
2049 boot, thus flooding the BOOTP server. Defining
2050 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
2051 inserted before sending out BOOTP requests. The
2052 following delays are inserted then:
2053
2054 1st BOOTP request: delay 0 ... 1 sec
2055 2nd BOOTP request: delay 0 ... 2 sec
2056 3rd BOOTP request: delay 0 ... 4 sec
2057 4th and following
2058 BOOTP requests: delay 0 ... 8 sec
2059
2060 CONFIG_BOOTP_ID_CACHE_SIZE
2061
2062 BOOTP packets are uniquely identified using a 32-bit ID. The
2063 server will copy the ID from client requests to responses and
2064 U-Boot will use this to determine if it is the destination of
2065 an incoming response. Some servers will check that addresses
2066 aren't in use before handing them out (usually using an ARP
2067 ping) and therefore take up to a few hundred milliseconds to
2068 respond. Network congestion may also influence the time it
2069 takes for a response to make it back to the client. If that
2070 time is too long, U-Boot will retransmit requests. In order
2071 to allow earlier responses to still be accepted after these
2072 retransmissions, U-Boot's BOOTP client keeps a small cache of
2073 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
2074 cache. The default is to keep IDs for up to four outstanding
2075 requests. Increasing this will allow U-Boot to accept offers
2076 from a BOOTP client in networks with unusually high latency.
2077
2078 - DHCP Advanced Options:
2079 You can fine tune the DHCP functionality by defining
2080 CONFIG_BOOTP_* symbols:
2081
2082 CONFIG_BOOTP_SUBNETMASK
2083 CONFIG_BOOTP_GATEWAY
2084 CONFIG_BOOTP_HOSTNAME
2085 CONFIG_BOOTP_NISDOMAIN
2086 CONFIG_BOOTP_BOOTPATH
2087 CONFIG_BOOTP_BOOTFILESIZE
2088 CONFIG_BOOTP_DNS
2089 CONFIG_BOOTP_DNS2
2090 CONFIG_BOOTP_SEND_HOSTNAME
2091 CONFIG_BOOTP_NTPSERVER
2092 CONFIG_BOOTP_TIMEOFFSET
2093 CONFIG_BOOTP_VENDOREX
2094 CONFIG_BOOTP_MAY_FAIL
2095
2096 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
2097 environment variable, not the BOOTP server.
2098
2099 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
2100 after the configured retry count, the call will fail
2101 instead of starting over. This can be used to fail over
2102 to Link-local IP address configuration if the DHCP server
2103 is not available.
2104
2105 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
2106 serverip from a DHCP server, it is possible that more
2107 than one DNS serverip is offered to the client.
2108 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
2109 serverip will be stored in the additional environment
2110 variable "dnsip2". The first DNS serverip is always
2111 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
2112 is defined.
2113
2114 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
2115 to do a dynamic update of a DNS server. To do this, they
2116 need the hostname of the DHCP requester.
2117 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
2118 of the "hostname" environment variable is passed as
2119 option 12 to the DHCP server.
2120
2121 CONFIG_BOOTP_DHCP_REQUEST_DELAY
2122
2123 A 32bit value in microseconds for a delay between
2124 receiving a "DHCP Offer" and sending the "DHCP Request".
2125 This fixes a problem with certain DHCP servers that don't
2126 respond 100% of the time to a "DHCP request". E.g. On an
2127 AT91RM9200 processor running at 180MHz, this delay needed
2128 to be *at least* 15,000 usec before a Windows Server 2003
2129 DHCP server would reply 100% of the time. I recommend at
2130 least 50,000 usec to be safe. The alternative is to hope
2131 that one of the retries will be successful but note that
2132 the DHCP timeout and retry process takes a longer than
2133 this delay.
2134
2135 - Link-local IP address negotiation:
2136 Negotiate with other link-local clients on the local network
2137 for an address that doesn't require explicit configuration.
2138 This is especially useful if a DHCP server cannot be guaranteed
2139 to exist in all environments that the device must operate.
2140
2141 See doc/README.link-local for more information.
2142
2143 - CDP Options:
2144 CONFIG_CDP_DEVICE_ID
2145
2146 The device id used in CDP trigger frames.
2147
2148 CONFIG_CDP_DEVICE_ID_PREFIX
2149
2150 A two character string which is prefixed to the MAC address
2151 of the device.
2152
2153 CONFIG_CDP_PORT_ID
2154
2155 A printf format string which contains the ascii name of
2156 the port. Normally is set to "eth%d" which sets
2157 eth0 for the first Ethernet, eth1 for the second etc.
2158
2159 CONFIG_CDP_CAPABILITIES
2160
2161 A 32bit integer which indicates the device capabilities;
2162 0x00000010 for a normal host which does not forwards.
2163
2164 CONFIG_CDP_VERSION
2165
2166 An ascii string containing the version of the software.
2167
2168 CONFIG_CDP_PLATFORM
2169
2170 An ascii string containing the name of the platform.
2171
2172 CONFIG_CDP_TRIGGER
2173
2174 A 32bit integer sent on the trigger.
2175
2176 CONFIG_CDP_POWER_CONSUMPTION
2177
2178 A 16bit integer containing the power consumption of the
2179 device in .1 of milliwatts.
2180
2181 CONFIG_CDP_APPLIANCE_VLAN_TYPE
2182
2183 A byte containing the id of the VLAN.
2184
2185 - Status LED: CONFIG_STATUS_LED
2186
2187 Several configurations allow to display the current
2188 status using a LED. For instance, the LED will blink
2189 fast while running U-Boot code, stop blinking as
2190 soon as a reply to a BOOTP request was received, and
2191 start blinking slow once the Linux kernel is running
2192 (supported by a status LED driver in the Linux
2193 kernel). Defining CONFIG_STATUS_LED enables this
2194 feature in U-Boot.
2195
2196 Additional options:
2197
2198 CONFIG_GPIO_LED
2199 The status LED can be connected to a GPIO pin.
2200 In such cases, the gpio_led driver can be used as a
2201 status LED backend implementation. Define CONFIG_GPIO_LED
2202 to include the gpio_led driver in the U-Boot binary.
2203
2204 CONFIG_GPIO_LED_INVERTED_TABLE
2205 Some GPIO connected LEDs may have inverted polarity in which
2206 case the GPIO high value corresponds to LED off state and
2207 GPIO low value corresponds to LED on state.
2208 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
2209 with a list of GPIO LEDs that have inverted polarity.
2210
2211 - CAN Support: CONFIG_CAN_DRIVER
2212
2213 Defining CONFIG_CAN_DRIVER enables CAN driver support
2214 on those systems that support this (optional)
2215 feature, like the TQM8xxL modules.
2216
2217 - I2C Support: CONFIG_SYS_I2C
2218
2219 This enable the NEW i2c subsystem, and will allow you to use
2220 i2c commands at the u-boot command line (as long as you set
2221 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
2222 based realtime clock chips or other i2c devices. See
2223 common/cmd_i2c.c for a description of the command line
2224 interface.
2225
2226 ported i2c driver to the new framework:
2227 - drivers/i2c/soft_i2c.c:
2228 - activate first bus with CONFIG_SYS_I2C_SOFT define
2229 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
2230 for defining speed and slave address
2231 - activate second bus with I2C_SOFT_DECLARATIONS2 define
2232 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
2233 for defining speed and slave address
2234 - activate third bus with I2C_SOFT_DECLARATIONS3 define
2235 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
2236 for defining speed and slave address
2237 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
2238 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
2239 for defining speed and slave address
2240
2241 - drivers/i2c/fsl_i2c.c:
2242 - activate i2c driver with CONFIG_SYS_I2C_FSL
2243 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
2244 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
2245 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
2246 bus.
2247 - If your board supports a second fsl i2c bus, define
2248 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
2249 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
2250 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2251 second bus.
2252
2253 - drivers/i2c/tegra_i2c.c:
2254 - activate this driver with CONFIG_SYS_I2C_TEGRA
2255 - This driver adds 4 i2c buses with a fix speed from
2256 100000 and the slave addr 0!
2257
2258 - drivers/i2c/ppc4xx_i2c.c
2259 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2260 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2261 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2262
2263 - drivers/i2c/i2c_mxc.c
2264 - activate this driver with CONFIG_SYS_I2C_MXC
2265 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2266 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2267 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2268 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2269 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2270 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2271 If thoses defines are not set, default value is 100000
2272 for speed, and 0 for slave.
2273
2274 - drivers/i2c/rcar_i2c.c:
2275 - activate this driver with CONFIG_SYS_I2C_RCAR
2276 - This driver adds 4 i2c buses
2277
2278 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2279 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2280 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2281 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2282 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2283 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2284 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2285 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2286 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2287
2288 - drivers/i2c/sh_i2c.c:
2289 - activate this driver with CONFIG_SYS_I2C_SH
2290 - This driver adds from 2 to 5 i2c buses
2291
2292 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
2293 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
2294 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
2295 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
2296 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
2297 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
2298 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
2299 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
2300 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
2301 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
2302 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
2303 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
2304 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses
2305
2306 - drivers/i2c/omap24xx_i2c.c
2307 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
2308 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
2309 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
2310 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
2311 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
2312 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
2313 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
2314 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
2315 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
2316 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
2317 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
2318
2319 - drivers/i2c/zynq_i2c.c
2320 - activate this driver with CONFIG_SYS_I2C_ZYNQ
2321 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
2322 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
2323
2324 - drivers/i2c/s3c24x0_i2c.c:
2325 - activate this driver with CONFIG_SYS_I2C_S3C24X0
2326 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
2327 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
2328 with a fix speed from 100000 and the slave addr 0!
2329
2330 - drivers/i2c/ihs_i2c.c
2331 - activate this driver with CONFIG_SYS_I2C_IHS
2332 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
2333 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
2334 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
2335 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
2336 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
2337 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
2338 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
2339 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
2340 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
2341 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
2342 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
2343 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
2344
2345 additional defines:
2346
2347 CONFIG_SYS_NUM_I2C_BUSES
2348 Hold the number of i2c busses you want to use. If you
2349 don't use/have i2c muxes on your i2c bus, this
2350 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2351 omit this define.
2352
2353 CONFIG_SYS_I2C_DIRECT_BUS
2354 define this, if you don't use i2c muxes on your hardware.
2355 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2356 omit this define.
2357
2358 CONFIG_SYS_I2C_MAX_HOPS
2359 define how many muxes are maximal consecutively connected
2360 on one i2c bus. If you not use i2c muxes, omit this
2361 define.
2362
2363 CONFIG_SYS_I2C_BUSES
2364 hold a list of busses you want to use, only used if
2365 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2366 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2367 CONFIG_SYS_NUM_I2C_BUSES = 9:
2368
2369 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2370 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2371 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2372 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2373 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2374 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2375 {1, {I2C_NULL_HOP}}, \
2376 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2377 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2378 }
2379
2380 which defines
2381 bus 0 on adapter 0 without a mux
2382 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2383 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2384 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2385 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2386 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2387 bus 6 on adapter 1 without a mux
2388 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2389 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2390
2391 If you do not have i2c muxes on your board, omit this define.
2392
2393 - Legacy I2C Support: CONFIG_HARD_I2C
2394
2395 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2396 provides the following compelling advantages:
2397
2398 - more than one i2c adapter is usable
2399 - approved multibus support
2400 - better i2c mux support
2401
2402 ** Please consider updating your I2C driver now. **
2403
2404 These enable legacy I2C serial bus commands. Defining
2405 CONFIG_HARD_I2C will include the appropriate I2C driver
2406 for the selected CPU.
2407
2408 This will allow you to use i2c commands at the u-boot
2409 command line (as long as you set CONFIG_CMD_I2C in
2410 CONFIG_COMMANDS) and communicate with i2c based realtime
2411 clock chips. See common/cmd_i2c.c for a description of the
2412 command line interface.
2413
2414 CONFIG_HARD_I2C selects a hardware I2C controller.
2415
2416 There are several other quantities that must also be
2417 defined when you define CONFIG_HARD_I2C.
2418
2419 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2420 to be the frequency (in Hz) at which you wish your i2c bus
2421 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2422 the CPU's i2c node address).
2423
2424 Now, the u-boot i2c code for the mpc8xx
2425 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2426 and so its address should therefore be cleared to 0 (See,
2427 eg, MPC823e User's Manual p.16-473). So, set
2428 CONFIG_SYS_I2C_SLAVE to 0.
2429
2430 CONFIG_SYS_I2C_INIT_MPC5XXX
2431
2432 When a board is reset during an i2c bus transfer
2433 chips might think that the current transfer is still
2434 in progress. Reset the slave devices by sending start
2435 commands until the slave device responds.
2436
2437 That's all that's required for CONFIG_HARD_I2C.
2438
2439 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2440 then the following macros need to be defined (examples are
2441 from include/configs/lwmon.h):
2442
2443 I2C_INIT
2444
2445 (Optional). Any commands necessary to enable the I2C
2446 controller or configure ports.
2447
2448 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2449
2450 I2C_PORT
2451
2452 (Only for MPC8260 CPU). The I/O port to use (the code
2453 assumes both bits are on the same port). Valid values
2454 are 0..3 for ports A..D.
2455
2456 I2C_ACTIVE
2457
2458 The code necessary to make the I2C data line active
2459 (driven). If the data line is open collector, this
2460 define can be null.
2461
2462 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2463
2464 I2C_TRISTATE
2465
2466 The code necessary to make the I2C data line tri-stated
2467 (inactive). If the data line is open collector, this
2468 define can be null.
2469
2470 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2471
2472 I2C_READ
2473
2474 Code that returns true if the I2C data line is high,
2475 false if it is low.
2476
2477 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2478
2479 I2C_SDA(bit)
2480
2481 If <bit> is true, sets the I2C data line high. If it
2482 is false, it clears it (low).
2483
2484 eg: #define I2C_SDA(bit) \
2485 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2486 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2487
2488 I2C_SCL(bit)
2489
2490 If <bit> is true, sets the I2C clock line high. If it
2491 is false, it clears it (low).
2492
2493 eg: #define I2C_SCL(bit) \
2494 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2495 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2496
2497 I2C_DELAY
2498
2499 This delay is invoked four times per clock cycle so this
2500 controls the rate of data transfer. The data rate thus
2501 is 1 / (I2C_DELAY * 4). Often defined to be something
2502 like:
2503
2504 #define I2C_DELAY udelay(2)
2505
2506 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2507
2508 If your arch supports the generic GPIO framework (asm/gpio.h),
2509 then you may alternatively define the two GPIOs that are to be
2510 used as SCL / SDA. Any of the previous I2C_xxx macros will
2511 have GPIO-based defaults assigned to them as appropriate.
2512
2513 You should define these to the GPIO value as given directly to
2514 the generic GPIO functions.
2515
2516 CONFIG_SYS_I2C_INIT_BOARD
2517
2518 When a board is reset during an i2c bus transfer
2519 chips might think that the current transfer is still
2520 in progress. On some boards it is possible to access
2521 the i2c SCLK line directly, either by using the
2522 processor pin as a GPIO or by having a second pin
2523 connected to the bus. If this option is defined a
2524 custom i2c_init_board() routine in boards/xxx/board.c
2525 is run early in the boot sequence.
2526
2527 CONFIG_SYS_I2C_BOARD_LATE_INIT
2528
2529 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2530 defined a custom i2c_board_late_init() routine in
2531 boards/xxx/board.c is run AFTER the operations in i2c_init()
2532 is completed. This callpoint can be used to unreset i2c bus
2533 using CPU i2c controller register accesses for CPUs whose i2c
2534 controller provide such a method. It is called at the end of
2535 i2c_init() to allow i2c_init operations to setup the i2c bus
2536 controller on the CPU (e.g. setting bus speed & slave address).
2537
2538 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2539
2540 This option enables configuration of bi_iic_fast[] flags
2541 in u-boot bd_info structure based on u-boot environment
2542 variable "i2cfast". (see also i2cfast)
2543
2544 CONFIG_I2C_MULTI_BUS
2545
2546 This option allows the use of multiple I2C buses, each of which
2547 must have a controller. At any point in time, only one bus is
2548 active. To switch to a different bus, use the 'i2c dev' command.
2549 Note that bus numbering is zero-based.
2550
2551 CONFIG_SYS_I2C_NOPROBES
2552
2553 This option specifies a list of I2C devices that will be skipped
2554 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2555 is set, specify a list of bus-device pairs. Otherwise, specify
2556 a 1D array of device addresses
2557
2558 e.g.
2559 #undef CONFIG_I2C_MULTI_BUS
2560 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2561
2562 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2563
2564 #define CONFIG_I2C_MULTI_BUS
2565 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2566
2567 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2568
2569 CONFIG_SYS_SPD_BUS_NUM
2570
2571 If defined, then this indicates the I2C bus number for DDR SPD.
2572 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2573
2574 CONFIG_SYS_RTC_BUS_NUM
2575
2576 If defined, then this indicates the I2C bus number for the RTC.
2577 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2578
2579 CONFIG_SYS_DTT_BUS_NUM
2580
2581 If defined, then this indicates the I2C bus number for the DTT.
2582 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2583
2584 CONFIG_SYS_I2C_DTT_ADDR:
2585
2586 If defined, specifies the I2C address of the DTT device.
2587 If not defined, then U-Boot uses predefined value for
2588 specified DTT device.
2589
2590 CONFIG_SOFT_I2C_READ_REPEATED_START
2591
2592 defining this will force the i2c_read() function in
2593 the soft_i2c driver to perform an I2C repeated start
2594 between writing the address pointer and reading the
2595 data. If this define is omitted the default behaviour
2596 of doing a stop-start sequence will be used. Most I2C
2597 devices can use either method, but some require one or
2598 the other.
2599
2600 - SPI Support: CONFIG_SPI
2601
2602 Enables SPI driver (so far only tested with
2603 SPI EEPROM, also an instance works with Crystal A/D and
2604 D/As on the SACSng board)
2605
2606 CONFIG_SH_SPI
2607
2608 Enables the driver for SPI controller on SuperH. Currently
2609 only SH7757 is supported.
2610
2611 CONFIG_SPI_X
2612
2613 Enables extended (16-bit) SPI EEPROM addressing.
2614 (symmetrical to CONFIG_I2C_X)
2615
2616 CONFIG_SOFT_SPI
2617
2618 Enables a software (bit-bang) SPI driver rather than
2619 using hardware support. This is a general purpose
2620 driver that only requires three general I/O port pins
2621 (two outputs, one input) to function. If this is
2622 defined, the board configuration must define several
2623 SPI configuration items (port pins to use, etc). For
2624 an example, see include/configs/sacsng.h.
2625
2626 CONFIG_HARD_SPI
2627
2628 Enables a hardware SPI driver for general-purpose reads
2629 and writes. As with CONFIG_SOFT_SPI, the board configuration
2630 must define a list of chip-select function pointers.
2631 Currently supported on some MPC8xxx processors. For an
2632 example, see include/configs/mpc8349emds.h.
2633
2634 CONFIG_MXC_SPI
2635
2636 Enables the driver for the SPI controllers on i.MX and MXC
2637 SoCs. Currently i.MX31/35/51 are supported.
2638
2639 CONFIG_SYS_SPI_MXC_WAIT
2640 Timeout for waiting until spi transfer completed.
2641 default: (CONFIG_SYS_HZ/100) /* 10 ms */
2642
2643 - FPGA Support: CONFIG_FPGA
2644
2645 Enables FPGA subsystem.
2646
2647 CONFIG_FPGA_<vendor>
2648
2649 Enables support for specific chip vendors.
2650 (ALTERA, XILINX)
2651
2652 CONFIG_FPGA_<family>
2653
2654 Enables support for FPGA family.
2655 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2656
2657 CONFIG_FPGA_COUNT
2658
2659 Specify the number of FPGA devices to support.
2660
2661 CONFIG_CMD_FPGA_LOADMK
2662
2663 Enable support for fpga loadmk command
2664
2665 CONFIG_CMD_FPGA_LOADP
2666
2667 Enable support for fpga loadp command - load partial bitstream
2668
2669 CONFIG_CMD_FPGA_LOADBP
2670
2671 Enable support for fpga loadbp command - load partial bitstream
2672 (Xilinx only)
2673
2674 CONFIG_SYS_FPGA_PROG_FEEDBACK
2675
2676 Enable printing of hash marks during FPGA configuration.
2677
2678 CONFIG_SYS_FPGA_CHECK_BUSY
2679
2680 Enable checks on FPGA configuration interface busy
2681 status by the configuration function. This option
2682 will require a board or device specific function to
2683 be written.
2684
2685 CONFIG_FPGA_DELAY
2686
2687 If defined, a function that provides delays in the FPGA
2688 configuration driver.
2689
2690 CONFIG_SYS_FPGA_CHECK_CTRLC
2691 Allow Control-C to interrupt FPGA configuration
2692
2693 CONFIG_SYS_FPGA_CHECK_ERROR
2694
2695 Check for configuration errors during FPGA bitfile
2696 loading. For example, abort during Virtex II
2697 configuration if the INIT_B line goes low (which
2698 indicated a CRC error).
2699
2700 CONFIG_SYS_FPGA_WAIT_INIT
2701
2702 Maximum time to wait for the INIT_B line to deassert
2703 after PROB_B has been deasserted during a Virtex II
2704 FPGA configuration sequence. The default time is 500
2705 ms.
2706
2707 CONFIG_SYS_FPGA_WAIT_BUSY
2708
2709 Maximum time to wait for BUSY to deassert during
2710 Virtex II FPGA configuration. The default is 5 ms.
2711
2712 CONFIG_SYS_FPGA_WAIT_CONFIG
2713
2714 Time to wait after FPGA configuration. The default is
2715 200 ms.
2716
2717 - Configuration Management:
2718 CONFIG_BUILD_TARGET
2719
2720 Some SoCs need special image types (e.g. U-Boot binary
2721 with a special header) as build targets. By defining
2722 CONFIG_BUILD_TARGET in the SoC / board header, this
2723 special image will be automatically built upon calling
2724 make / MAKEALL.
2725
2726 CONFIG_IDENT_STRING
2727
2728 If defined, this string will be added to the U-Boot
2729 version information (U_BOOT_VERSION)
2730
2731 - Vendor Parameter Protection:
2732
2733 U-Boot considers the values of the environment
2734 variables "serial#" (Board Serial Number) and
2735 "ethaddr" (Ethernet Address) to be parameters that
2736 are set once by the board vendor / manufacturer, and
2737 protects these variables from casual modification by
2738 the user. Once set, these variables are read-only,
2739 and write or delete attempts are rejected. You can
2740 change this behaviour:
2741
2742 If CONFIG_ENV_OVERWRITE is #defined in your config
2743 file, the write protection for vendor parameters is
2744 completely disabled. Anybody can change or delete
2745 these parameters.
2746
2747 Alternatively, if you #define _both_ CONFIG_ETHADDR
2748 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2749 Ethernet address is installed in the environment,
2750 which can be changed exactly ONCE by the user. [The
2751 serial# is unaffected by this, i. e. it remains
2752 read-only.]
2753
2754 The same can be accomplished in a more flexible way
2755 for any variable by configuring the type of access
2756 to allow for those variables in the ".flags" variable
2757 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2758
2759 - Protected RAM:
2760 CONFIG_PRAM
2761
2762 Define this variable to enable the reservation of
2763 "protected RAM", i. e. RAM which is not overwritten
2764 by U-Boot. Define CONFIG_PRAM to hold the number of
2765 kB you want to reserve for pRAM. You can overwrite
2766 this default value by defining an environment
2767 variable "pram" to the number of kB you want to
2768 reserve. Note that the board info structure will
2769 still show the full amount of RAM. If pRAM is
2770 reserved, a new environment variable "mem" will
2771 automatically be defined to hold the amount of
2772 remaining RAM in a form that can be passed as boot
2773 argument to Linux, for instance like that:
2774
2775 setenv bootargs ... mem=\${mem}
2776 saveenv
2777
2778 This way you can tell Linux not to use this memory,
2779 either, which results in a memory region that will
2780 not be affected by reboots.
2781
2782 *WARNING* If your board configuration uses automatic
2783 detection of the RAM size, you must make sure that
2784 this memory test is non-destructive. So far, the
2785 following board configurations are known to be
2786 "pRAM-clean":
2787
2788 IVMS8, IVML24, SPD8xx, TQM8xxL,
2789 HERMES, IP860, RPXlite, LWMON,
2790 FLAGADM, TQM8260
2791
2792 - Access to physical memory region (> 4GB)
2793 Some basic support is provided for operations on memory not
2794 normally accessible to U-Boot - e.g. some architectures
2795 support access to more than 4GB of memory on 32-bit
2796 machines using physical address extension or similar.
2797 Define CONFIG_PHYSMEM to access this basic support, which
2798 currently only supports clearing the memory.
2799
2800 - Error Recovery:
2801 CONFIG_PANIC_HANG
2802
2803 Define this variable to stop the system in case of a
2804 fatal error, so that you have to reset it manually.
2805 This is probably NOT a good idea for an embedded
2806 system where you want the system to reboot
2807 automatically as fast as possible, but it may be
2808 useful during development since you can try to debug
2809 the conditions that lead to the situation.
2810
2811 CONFIG_NET_RETRY_COUNT
2812
2813 This variable defines the number of retries for
2814 network operations like ARP, RARP, TFTP, or BOOTP
2815 before giving up the operation. If not defined, a
2816 default value of 5 is used.
2817
2818 CONFIG_ARP_TIMEOUT
2819
2820 Timeout waiting for an ARP reply in milliseconds.
2821
2822 CONFIG_NFS_TIMEOUT
2823
2824 Timeout in milliseconds used in NFS protocol.
2825 If you encounter "ERROR: Cannot umount" in nfs command,
2826 try longer timeout such as
2827 #define CONFIG_NFS_TIMEOUT 10000UL
2828
2829 - Command Interpreter:
2830 CONFIG_AUTO_COMPLETE
2831
2832 Enable auto completion of commands using TAB.
2833
2834 CONFIG_SYS_HUSH_PARSER
2835
2836 Define this variable to enable the "hush" shell (from
2837 Busybox) as command line interpreter, thus enabling
2838 powerful command line syntax like
2839 if...then...else...fi conditionals or `&&' and '||'
2840 constructs ("shell scripts").
2841
2842 If undefined, you get the old, much simpler behaviour
2843 with a somewhat smaller memory footprint.
2844
2845
2846 CONFIG_SYS_PROMPT_HUSH_PS2
2847
2848 This defines the secondary prompt string, which is
2849 printed when the command interpreter needs more input
2850 to complete a command. Usually "> ".
2851
2852 Note:
2853
2854 In the current implementation, the local variables
2855 space and global environment variables space are
2856 separated. Local variables are those you define by
2857 simply typing `name=value'. To access a local
2858 variable later on, you have write `$name' or
2859 `${name}'; to execute the contents of a variable
2860 directly type `$name' at the command prompt.
2861
2862 Global environment variables are those you use
2863 setenv/printenv to work with. To run a command stored
2864 in such a variable, you need to use the run command,
2865 and you must not use the '$' sign to access them.
2866
2867 To store commands and special characters in a
2868 variable, please use double quotation marks
2869 surrounding the whole text of the variable, instead
2870 of the backslashes before semicolons and special
2871 symbols.
2872
2873 - Commandline Editing and History:
2874 CONFIG_CMDLINE_EDITING
2875
2876 Enable editing and History functions for interactive
2877 commandline input operations
2878
2879 - Default Environment:
2880 CONFIG_EXTRA_ENV_SETTINGS
2881
2882 Define this to contain any number of null terminated
2883 strings (variable = value pairs) that will be part of
2884 the default environment compiled into the boot image.
2885
2886 For example, place something like this in your
2887 board's config file:
2888
2889 #define CONFIG_EXTRA_ENV_SETTINGS \
2890 "myvar1=value1\0" \
2891 "myvar2=value2\0"
2892
2893 Warning: This method is based on knowledge about the
2894 internal format how the environment is stored by the
2895 U-Boot code. This is NOT an official, exported
2896 interface! Although it is unlikely that this format
2897 will change soon, there is no guarantee either.
2898 You better know what you are doing here.
2899
2900 Note: overly (ab)use of the default environment is
2901 discouraged. Make sure to check other ways to preset
2902 the environment like the "source" command or the
2903 boot command first.
2904
2905 CONFIG_ENV_VARS_UBOOT_CONFIG
2906
2907 Define this in order to add variables describing the
2908 U-Boot build configuration to the default environment.
2909 These will be named arch, cpu, board, vendor, and soc.
2910
2911 Enabling this option will cause the following to be defined:
2912
2913 - CONFIG_SYS_ARCH
2914 - CONFIG_SYS_CPU
2915 - CONFIG_SYS_BOARD
2916 - CONFIG_SYS_VENDOR
2917 - CONFIG_SYS_SOC
2918
2919 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2920
2921 Define this in order to add variables describing certain
2922 run-time determined information about the hardware to the
2923 environment. These will be named board_name, board_rev.
2924
2925 CONFIG_DELAY_ENVIRONMENT
2926
2927 Normally the environment is loaded when the board is
2928 intialised so that it is available to U-Boot. This inhibits
2929 that so that the environment is not available until
2930 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2931 this is instead controlled by the value of
2932 /config/load-environment.
2933
2934 - DataFlash Support:
2935 CONFIG_HAS_DATAFLASH
2936
2937 Defining this option enables DataFlash features and
2938 allows to read/write in Dataflash via the standard
2939 commands cp, md...
2940
2941 - Serial Flash support
2942 CONFIG_CMD_SF
2943
2944 Defining this option enables SPI flash commands
2945 'sf probe/read/write/erase/update'.
2946
2947 Usage requires an initial 'probe' to define the serial
2948 flash parameters, followed by read/write/erase/update
2949 commands.
2950
2951 The following defaults may be provided by the platform
2952 to handle the common case when only a single serial
2953 flash is present on the system.
2954
2955 CONFIG_SF_DEFAULT_BUS Bus identifier
2956 CONFIG_SF_DEFAULT_CS Chip-select
2957 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2958 CONFIG_SF_DEFAULT_SPEED in Hz
2959
2960 CONFIG_CMD_SF_TEST
2961
2962 Define this option to include a destructive SPI flash
2963 test ('sf test').
2964
2965 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2966
2967 Define this option to use the Bank addr/Extended addr
2968 support on SPI flashes which has size > 16Mbytes.
2969
2970 CONFIG_SF_DUAL_FLASH Dual flash memories
2971
2972 Define this option to use dual flash support where two flash
2973 memories can be connected with a given cs line.
2974 currently Xilinx Zynq qspi support these type of connections.
2975
2976 CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
2977 enable the W#/Vpp signal to disable writing to the status
2978 register on ST MICRON flashes like the N25Q128.
2979 The status register write enable/disable bit, combined with
2980 the W#/VPP signal provides hardware data protection for the
2981 device as follows: When the enable/disable bit is set to 1,
2982 and the W#/VPP signal is driven LOW, the status register
2983 nonvolatile bits become read-only and the WRITE STATUS REGISTER
2984 operation will not execute. The only way to exit this
2985 hardware-protected mode is to drive W#/VPP HIGH.
2986
2987 - SystemACE Support:
2988 CONFIG_SYSTEMACE
2989
2990 Adding this option adds support for Xilinx SystemACE
2991 chips attached via some sort of local bus. The address
2992 of the chip must also be defined in the
2993 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2994
2995 #define CONFIG_SYSTEMACE
2996 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2997
2998 When SystemACE support is added, the "ace" device type
2999 becomes available to the fat commands, i.e. fatls.
3000
3001 - TFTP Fixed UDP Port:
3002 CONFIG_TFTP_PORT
3003
3004 If this is defined, the environment variable tftpsrcp
3005 is used to supply the TFTP UDP source port value.
3006 If tftpsrcp isn't defined, the normal pseudo-random port
3007 number generator is used.
3008
3009 Also, the environment variable tftpdstp is used to supply
3010 the TFTP UDP destination port value. If tftpdstp isn't
3011 defined, the normal port 69 is used.
3012
3013 The purpose for tftpsrcp is to allow a TFTP server to
3014 blindly start the TFTP transfer using the pre-configured
3015 target IP address and UDP port. This has the effect of
3016 "punching through" the (Windows XP) firewall, allowing
3017 the remainder of the TFTP transfer to proceed normally.
3018 A better solution is to properly configure the firewall,
3019 but sometimes that is not allowed.
3020
3021 - Hashing support:
3022 CONFIG_CMD_HASH
3023
3024 This enables a generic 'hash' command which can produce
3025 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
3026
3027 CONFIG_HASH_VERIFY
3028
3029 Enable the hash verify command (hash -v). This adds to code
3030 size a little.
3031
3032 CONFIG_SHA1 - support SHA1 hashing
3033 CONFIG_SHA256 - support SHA256 hashing
3034
3035 Note: There is also a sha1sum command, which should perhaps
3036 be deprecated in favour of 'hash sha1'.
3037
3038 - Freescale i.MX specific commands:
3039 CONFIG_CMD_HDMIDETECT
3040 This enables 'hdmidet' command which returns true if an
3041 HDMI monitor is detected. This command is i.MX 6 specific.
3042
3043 CONFIG_CMD_BMODE
3044 This enables the 'bmode' (bootmode) command for forcing
3045 a boot from specific media.
3046
3047 This is useful for forcing the ROM's usb downloader to
3048 activate upon a watchdog reset which is nice when iterating
3049 on U-Boot. Using the reset button or running bmode normal
3050 will set it back to normal. This command currently
3051 supports i.MX53 and i.MX6.
3052
3053 - Signing support:
3054 CONFIG_RSA
3055
3056 This enables the RSA algorithm used for FIT image verification
3057 in U-Boot. See doc/uImage.FIT/signature.txt for more information.
3058
3059 The signing part is build into mkimage regardless of this
3060 option.
3061
3062 - bootcount support:
3063 CONFIG_BOOTCOUNT_LIMIT
3064
3065 This enables the bootcounter support, see:
3066 http://www.denx.de/wiki/DULG/UBootBootCountLimit
3067
3068 CONFIG_AT91SAM9XE
3069 enable special bootcounter support on at91sam9xe based boards.
3070 CONFIG_BLACKFIN
3071 enable special bootcounter support on blackfin based boards.
3072 CONFIG_SOC_DA8XX
3073 enable special bootcounter support on da850 based boards.
3074 CONFIG_BOOTCOUNT_RAM
3075 enable support for the bootcounter in RAM
3076 CONFIG_BOOTCOUNT_I2C
3077 enable support for the bootcounter on an i2c (like RTC) device.
3078 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
3079 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
3080 the bootcounter.
3081 CONFIG_BOOTCOUNT_ALEN = address len
3082
3083 - Show boot progress:
3084 CONFIG_SHOW_BOOT_PROGRESS
3085
3086 Defining this option allows to add some board-
3087 specific code (calling a user-provided function
3088 "show_boot_progress(int)") that enables you to show
3089 the system's boot progress on some display (for
3090 example, some LED's) on your board. At the moment,
3091 the following checkpoints are implemented:
3092
3093 - Detailed boot stage timing
3094 CONFIG_BOOTSTAGE
3095 Define this option to get detailed timing of each stage
3096 of the boot process.
3097
3098 CONFIG_BOOTSTAGE_USER_COUNT
3099 This is the number of available user bootstage records.
3100 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
3101 a new ID will be allocated from this stash. If you exceed
3102 the limit, recording will stop.
3103
3104 CONFIG_BOOTSTAGE_REPORT
3105 Define this to print a report before boot, similar to this:
3106
3107 Timer summary in microseconds:
3108 Mark Elapsed Stage
3109 0 0 reset
3110 3,575,678 3,575,678 board_init_f start
3111 3,575,695 17 arch_cpu_init A9
3112 3,575,777 82 arch_cpu_init done
3113 3,659,598 83,821 board_init_r start
3114 3,910,375 250,777 main_loop
3115 29,916,167 26,005,792 bootm_start
3116 30,361,327 445,160 start_kernel
3117
3118 CONFIG_CMD_BOOTSTAGE
3119 Add a 'bootstage' command which supports printing a report
3120 and un/stashing of bootstage data.
3121
3122 CONFIG_BOOTSTAGE_FDT
3123 Stash the bootstage information in the FDT. A root 'bootstage'
3124 node is created with each bootstage id as a child. Each child
3125 has a 'name' property and either 'mark' containing the
3126 mark time in microsecond, or 'accum' containing the
3127 accumulated time for that bootstage id in microseconds.
3128 For example:
3129
3130 bootstage {
3131 154 {
3132 name = "board_init_f";
3133 mark = <3575678>;
3134 };
3135 170 {
3136 name = "lcd";
3137 accum = <33482>;
3138 };
3139 };
3140
3141 Code in the Linux kernel can find this in /proc/devicetree.
3142
3143 Legacy uImage format:
3144
3145 Arg Where When
3146 1 common/cmd_bootm.c before attempting to boot an image
3147 -1 common/cmd_bootm.c Image header has bad magic number
3148 2 common/cmd_bootm.c Image header has correct magic number
3149 -2 common/cmd_bootm.c Image header has bad checksum
3150 3 common/cmd_bootm.c Image header has correct checksum
3151 -3 common/cmd_bootm.c Image data has bad checksum
3152 4 common/cmd_bootm.c Image data has correct checksum
3153 -4 common/cmd_bootm.c Image is for unsupported architecture
3154 5 common/cmd_bootm.c Architecture check OK
3155 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
3156 6 common/cmd_bootm.c Image Type check OK
3157 -6 common/cmd_bootm.c gunzip uncompression error
3158 -7 common/cmd_bootm.c Unimplemented compression type
3159 7 common/cmd_bootm.c Uncompression OK
3160 8 common/cmd_bootm.c No uncompress/copy overwrite error
3161 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
3162
3163 9 common/image.c Start initial ramdisk verification
3164 -10 common/image.c Ramdisk header has bad magic number
3165 -11 common/image.c Ramdisk header has bad checksum
3166 10 common/image.c Ramdisk header is OK
3167 -12 common/image.c Ramdisk data has bad checksum
3168 11 common/image.c Ramdisk data has correct checksum
3169 12 common/image.c Ramdisk verification complete, start loading
3170 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
3171 13 common/image.c Start multifile image verification
3172 14 common/image.c No initial ramdisk, no multifile, continue.
3173
3174 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
3175
3176 -30 arch/powerpc/lib/board.c Fatal error, hang the system
3177 -31 post/post.c POST test failed, detected by post_output_backlog()
3178 -32 post/post.c POST test failed, detected by post_run_single()
3179
3180 34 common/cmd_doc.c before loading a Image from a DOC device
3181 -35 common/cmd_doc.c Bad usage of "doc" command
3182 35 common/cmd_doc.c correct usage of "doc" command
3183 -36 common/cmd_doc.c No boot device
3184 36 common/cmd_doc.c correct boot device
3185 -37 common/cmd_doc.c Unknown Chip ID on boot device
3186 37 common/cmd_doc.c correct chip ID found, device available
3187 -38 common/cmd_doc.c Read Error on boot device
3188 38 common/cmd_doc.c reading Image header from DOC device OK
3189 -39 common/cmd_doc.c Image header has bad magic number
3190 39 common/cmd_doc.c Image header has correct magic number
3191 -40 common/cmd_doc.c Error reading Image from DOC device
3192 40 common/cmd_doc.c Image header has correct magic number
3193 41 common/cmd_ide.c before loading a Image from a IDE device
3194 -42 common/cmd_ide.c Bad usage of "ide" command
3195 42 common/cmd_ide.c correct usage of "ide" command
3196 -43 common/cmd_ide.c No boot device
3197 43 common/cmd_ide.c boot device found
3198 -44 common/cmd_ide.c Device not available
3199 44 common/cmd_ide.c Device available
3200 -45 common/cmd_ide.c wrong partition selected
3201 45 common/cmd_ide.c partition selected
3202 -46 common/cmd_ide.c Unknown partition table
3203 46 common/cmd_ide.c valid partition table found
3204 -47 common/cmd_ide.c Invalid partition type
3205 47 common/cmd_ide.c correct partition type
3206 -48 common/cmd_ide.c Error reading Image Header on boot device
3207 48 common/cmd_ide.c reading Image Header from IDE device OK
3208 -49 common/cmd_ide.c Image header has bad magic number
3209 49 common/cmd_ide.c Image header has correct magic number
3210 -50 common/cmd_ide.c Image header has bad checksum
3211 50 common/cmd_ide.c Image header has correct checksum
3212 -51 common/cmd_ide.c Error reading Image from IDE device
3213 51 common/cmd_ide.c reading Image from IDE device OK
3214 52 common/cmd_nand.c before loading a Image from a NAND device
3215 -53 common/cmd_nand.c Bad usage of "nand" command
3216 53 common/cmd_nand.c correct usage of "nand" command
3217 -54 common/cmd_nand.c No boot device
3218 54 common/cmd_nand.c boot device found
3219 -55 common/cmd_nand.c Unknown Chip ID on boot device
3220 55 common/cmd_nand.c correct chip ID found, device available
3221 -56 common/cmd_nand.c Error reading Image Header on boot device
3222 56 common/cmd_nand.c reading Image Header from NAND device OK
3223 -57 common/cmd_nand.c Image header has bad magic number
3224 57 common/cmd_nand.c Image header has correct magic number
3225 -58 common/cmd_nand.c Error reading Image from NAND device
3226 58 common/cmd_nand.c reading Image from NAND device OK
3227
3228 -60 common/env_common.c Environment has a bad CRC, using default
3229
3230 64 net/eth.c starting with Ethernet configuration.
3231 -64 net/eth.c no Ethernet found.
3232 65 net/eth.c Ethernet found.
3233
3234 -80 common/cmd_net.c usage wrong
3235 80 common/cmd_net.c before calling NetLoop()
3236 -81 common/cmd_net.c some error in NetLoop() occurred
3237 81 common/cmd_net.c NetLoop() back without error
3238 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
3239 82 common/cmd_net.c trying automatic boot
3240 83 common/cmd_net.c running "source" command
3241 -83 common/cmd_net.c some error in automatic boot or "source" command
3242 84 common/cmd_net.c end without errors
3243
3244 FIT uImage format:
3245
3246 Arg Where When
3247 100 common/cmd_bootm.c Kernel FIT Image has correct format
3248 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
3249 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
3250 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
3251 102 common/cmd_bootm.c Kernel unit name specified
3252 -103 common/cmd_bootm.c Can't get kernel subimage node offset
3253 103 common/cmd_bootm.c Found configuration node
3254 104 common/cmd_bootm.c Got kernel subimage node offset
3255 -104 common/cmd_bootm.c Kernel subimage hash verification failed
3256 105 common/cmd_bootm.c Kernel subimage hash verification OK
3257 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
3258 106 common/cmd_bootm.c Architecture check OK
3259 -106 common/cmd_bootm.c Kernel subimage has wrong type
3260 107 common/cmd_bootm.c Kernel subimage type OK
3261 -107 common/cmd_bootm.c Can't get kernel subimage data/size
3262 108 common/cmd_bootm.c Got kernel subimage data/size
3263 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
3264 -109 common/cmd_bootm.c Can't get kernel subimage type
3265 -110 common/cmd_bootm.c Can't get kernel subimage comp
3266 -111 common/cmd_bootm.c Can't get kernel subimage os
3267 -112 common/cmd_bootm.c Can't get kernel subimage load address
3268 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
3269
3270 120 common/image.c Start initial ramdisk verification
3271 -120 common/image.c Ramdisk FIT image has incorrect format
3272 121 common/image.c Ramdisk FIT image has correct format
3273 122 common/image.c No ramdisk subimage unit name, using configuration
3274 -122 common/image.c Can't get configuration for ramdisk subimage
3275 123 common/image.c Ramdisk unit name specified
3276 -124 common/image.c Can't get ramdisk subimage node offset
3277 125 common/image.c Got ramdisk subimage node offset
3278 -125 common/image.c Ramdisk subimage hash verification failed
3279 126 common/image.c Ramdisk subimage hash verification OK
3280 -126 common/image.c Ramdisk subimage for unsupported architecture
3281 127 common/image.c Architecture check OK
3282 -127 common/image.c Can't get ramdisk subimage data/size
3283 128 common/image.c Got ramdisk subimage data/size
3284 129 common/image.c Can't get ramdisk load address
3285 -129 common/image.c Got ramdisk load address
3286
3287 -130 common/cmd_doc.c Incorrect FIT image format
3288 131 common/cmd_doc.c FIT image format OK
3289
3290 -140 common/cmd_ide.c Incorrect FIT image format
3291 141 common/cmd_ide.c FIT image format OK
3292
3293 -150 common/cmd_nand.c Incorrect FIT image format
3294 151 common/cmd_nand.c FIT image format OK
3295
3296 - legacy image format:
3297 CONFIG_IMAGE_FORMAT_LEGACY
3298 enables the legacy image format support in U-Boot.
3299
3300 Default:
3301 enabled if CONFIG_FIT_SIGNATURE is not defined.
3302
3303 CONFIG_DISABLE_IMAGE_LEGACY
3304 disable the legacy image format
3305
3306 This define is introduced, as the legacy image format is
3307 enabled per default for backward compatibility.
3308
3309 - FIT image support:
3310 CONFIG_FIT
3311 Enable support for the FIT uImage format.
3312
3313 CONFIG_FIT_BEST_MATCH
3314 When no configuration is explicitly selected, default to the
3315 one whose fdt's compatibility field best matches that of
3316 U-Boot itself. A match is considered "best" if it matches the
3317 most specific compatibility entry of U-Boot's fdt's root node.
3318 The order of entries in the configuration's fdt is ignored.
3319
3320 CONFIG_FIT_SIGNATURE
3321 This option enables signature verification of FIT uImages,
3322 using a hash signed and verified using RSA. See
3323 doc/uImage.FIT/signature.txt for more details.
3324
3325 WARNING: When relying on signed FIT images with required
3326 signature check the legacy image format is default
3327 disabled. If a board need legacy image format support
3328 enable this through CONFIG_IMAGE_FORMAT_LEGACY
3329
3330 CONFIG_FIT_DISABLE_SHA256
3331 Supporting SHA256 hashes has quite an impact on binary size.
3332 For constrained systems sha256 hash support can be disabled
3333 with this option.
3334
3335 - Standalone program support:
3336 CONFIG_STANDALONE_LOAD_ADDR
3337
3338 This option defines a board specific value for the
3339 address where standalone program gets loaded, thus
3340 overwriting the architecture dependent default
3341 settings.
3342
3343 - Frame Buffer Address:
3344 CONFIG_FB_ADDR
3345
3346 Define CONFIG_FB_ADDR if you want to use specific
3347 address for frame buffer. This is typically the case
3348 when using a graphics controller has separate video
3349 memory. U-Boot will then place the frame buffer at
3350 the given address instead of dynamically reserving it
3351 in system RAM by calling lcd_setmem(), which grabs
3352 the memory for the frame buffer depending on the
3353 configured panel size.
3354
3355 Please see board_init_f function.
3356
3357 - Automatic software updates via TFTP server
3358 CONFIG_UPDATE_TFTP
3359 CONFIG_UPDATE_TFTP_CNT_MAX
3360 CONFIG_UPDATE_TFTP_MSEC_MAX
3361
3362 These options enable and control the auto-update feature;
3363 for a more detailed description refer to doc/README.update.
3364
3365 - MTD Support (mtdparts command, UBI support)
3366 CONFIG_MTD_DEVICE
3367
3368 Adds the MTD device infrastructure from the Linux kernel.
3369 Needed for mtdparts command support.
3370
3371 CONFIG_MTD_PARTITIONS
3372
3373 Adds the MTD partitioning infrastructure from the Linux
3374 kernel. Needed for UBI support.
3375
3376 CONFIG_MTD_NAND_VERIFY_WRITE
3377 verify if the written data is correct reread.
3378
3379 - UBI support
3380 CONFIG_CMD_UBI
3381
3382 Adds commands for interacting with MTD partitions formatted
3383 with the UBI flash translation layer
3384
3385 Requires also defining CONFIG_RBTREE
3386
3387 CONFIG_UBI_SILENCE_MSG
3388
3389 Make the verbose messages from UBI stop printing. This leaves
3390 warnings and errors enabled.
3391
3392
3393 CONFIG_MTD_UBI_WL_THRESHOLD
3394 This parameter defines the maximum difference between the highest
3395 erase counter value and the lowest erase counter value of eraseblocks
3396 of UBI devices. When this threshold is exceeded, UBI starts performing
3397 wear leveling by means of moving data from eraseblock with low erase
3398 counter to eraseblocks with high erase counter.
3399
3400 The default value should be OK for SLC NAND flashes, NOR flashes and
3401 other flashes which have eraseblock life-cycle 100000 or more.
3402 However, in case of MLC NAND flashes which typically have eraseblock
3403 life-cycle less than 10000, the threshold should be lessened (e.g.,
3404 to 128 or 256, although it does not have to be power of 2).
3405
3406 default: 4096
3407
3408 CONFIG_MTD_UBI_BEB_LIMIT
3409 This option specifies the maximum bad physical eraseblocks UBI
3410 expects on the MTD device (per 1024 eraseblocks). If the
3411 underlying flash does not admit of bad eraseblocks (e.g. NOR
3412 flash), this value is ignored.
3413
3414 NAND datasheets often specify the minimum and maximum NVM
3415 (Number of Valid Blocks) for the flashes' endurance lifetime.
3416 The maximum expected bad eraseblocks per 1024 eraseblocks
3417 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
3418 which gives 20 for most NANDs (MaxNVB is basically the total
3419 count of eraseblocks on the chip).
3420
3421 To put it differently, if this value is 20, UBI will try to
3422 reserve about 1.9% of physical eraseblocks for bad blocks
3423 handling. And that will be 1.9% of eraseblocks on the entire
3424 NAND chip, not just the MTD partition UBI attaches. This means
3425 that if you have, say, a NAND flash chip admits maximum 40 bad
3426 eraseblocks, and it is split on two MTD partitions of the same
3427 size, UBI will reserve 40 eraseblocks when attaching a
3428 partition.
3429
3430 default: 20
3431
3432 CONFIG_MTD_UBI_FASTMAP
3433 Fastmap is a mechanism which allows attaching an UBI device
3434 in nearly constant time. Instead of scanning the whole MTD device it
3435 only has to locate a checkpoint (called fastmap) on the device.
3436 The on-flash fastmap contains all information needed to attach
3437 the device. Using fastmap makes only sense on large devices where
3438 attaching by scanning takes long. UBI will not automatically install
3439 a fastmap on old images, but you can set the UBI parameter
3440 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
3441 that fastmap-enabled images are still usable with UBI implementations
3442 without fastmap support. On typical flash devices the whole fastmap
3443 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
3444
3445 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
3446 Set this parameter to enable fastmap automatically on images
3447 without a fastmap.
3448 default: 0
3449
3450 - UBIFS support
3451 CONFIG_CMD_UBIFS
3452
3453 Adds commands for interacting with UBI volumes formatted as
3454 UBIFS. UBIFS is read-only in u-boot.
3455
3456 Requires UBI support as well as CONFIG_LZO
3457
3458 CONFIG_UBIFS_SILENCE_MSG
3459
3460 Make the verbose messages from UBIFS stop printing. This leaves
3461 warnings and errors enabled.
3462
3463 - SPL framework
3464 CONFIG_SPL
3465 Enable building of SPL globally.
3466
3467 CONFIG_SPL_LDSCRIPT
3468 LDSCRIPT for linking the SPL binary.
3469
3470 CONFIG_SPL_MAX_FOOTPRINT
3471 Maximum size in memory allocated to the SPL, BSS included.
3472 When defined, the linker checks that the actual memory
3473 used by SPL from _start to __bss_end does not exceed it.
3474 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3475 must not be both defined at the same time.
3476
3477 CONFIG_SPL_MAX_SIZE
3478 Maximum size of the SPL image (text, data, rodata, and
3479 linker lists sections), BSS excluded.
3480 When defined, the linker checks that the actual size does
3481 not exceed it.
3482
3483 CONFIG_SPL_TEXT_BASE
3484 TEXT_BASE for linking the SPL binary.
3485
3486 CONFIG_SPL_RELOC_TEXT_BASE
3487 Address to relocate to. If unspecified, this is equal to
3488 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3489
3490 CONFIG_SPL_BSS_START_ADDR
3491 Link address for the BSS within the SPL binary.
3492
3493 CONFIG_SPL_BSS_MAX_SIZE
3494 Maximum size in memory allocated to the SPL BSS.
3495 When defined, the linker checks that the actual memory used
3496 by SPL from __bss_start to __bss_end does not exceed it.
3497 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3498 must not be both defined at the same time.
3499
3500 CONFIG_SPL_STACK
3501 Adress of the start of the stack SPL will use
3502
3503 CONFIG_SPL_RELOC_STACK
3504 Adress of the start of the stack SPL will use after
3505 relocation. If unspecified, this is equal to
3506 CONFIG_SPL_STACK.
3507
3508 CONFIG_SYS_SPL_MALLOC_START
3509 Starting address of the malloc pool used in SPL.
3510
3511 CONFIG_SYS_SPL_MALLOC_SIZE
3512 The size of the malloc pool used in SPL.
3513
3514 CONFIG_SPL_FRAMEWORK
3515 Enable the SPL framework under common/. This framework
3516 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3517 NAND loading of the Linux Kernel.
3518
3519 CONFIG_SPL_OS_BOOT
3520 Enable booting directly to an OS from SPL.
3521 See also: doc/README.falcon
3522
3523 CONFIG_SPL_DISPLAY_PRINT
3524 For ARM, enable an optional function to print more information
3525 about the running system.
3526
3527 CONFIG_SPL_INIT_MINIMAL
3528 Arch init code should be built for a very small image
3529
3530 CONFIG_SPL_LIBCOMMON_SUPPORT
3531 Support for common/libcommon.o in SPL binary
3532
3533 CONFIG_SPL_LIBDISK_SUPPORT
3534 Support for disk/libdisk.o in SPL binary
3535
3536 CONFIG_SPL_I2C_SUPPORT
3537 Support for drivers/i2c/libi2c.o in SPL binary
3538
3539 CONFIG_SPL_GPIO_SUPPORT
3540 Support for drivers/gpio/libgpio.o in SPL binary
3541
3542 CONFIG_SPL_MMC_SUPPORT
3543 Support for drivers/mmc/libmmc.o in SPL binary
3544
3545 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3546 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3547 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3548 Address, size and partition on the MMC to load U-Boot from
3549 when the MMC is being used in raw mode.
3550
3551 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3552 Sector to load kernel uImage from when MMC is being
3553 used in raw mode (for Falcon mode)
3554
3555 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3556 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3557 Sector and number of sectors to load kernel argument
3558 parameters from when MMC is being used in raw mode
3559 (for falcon mode)
3560
3561 CONFIG_SPL_FAT_SUPPORT
3562 Support for fs/fat/libfat.o in SPL binary
3563
3564 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3565 Filename to read to load U-Boot when reading from FAT
3566
3567 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3568 Filename to read to load kernel uImage when reading
3569 from FAT (for Falcon mode)
3570
3571 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3572 Filename to read to load kernel argument parameters
3573 when reading from FAT (for Falcon mode)
3574
3575 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3576 Set this for NAND SPL on PPC mpc83xx targets, so that
3577 start.S waits for the rest of the SPL to load before
3578 continuing (the hardware starts execution after just
3579 loading the first page rather than the full 4K).
3580
3581 CONFIG_SPL_SKIP_RELOCATE
3582 Avoid SPL relocation
3583
3584 CONFIG_SPL_NAND_BASE
3585 Include nand_base.c in the SPL. Requires
3586 CONFIG_SPL_NAND_DRIVERS.
3587
3588 CONFIG_SPL_NAND_DRIVERS
3589 SPL uses normal NAND drivers, not minimal drivers.
3590
3591 CONFIG_SPL_NAND_ECC
3592 Include standard software ECC in the SPL
3593
3594 CONFIG_SPL_NAND_SIMPLE
3595 Support for NAND boot using simple NAND drivers that
3596 expose the cmd_ctrl() interface.
3597
3598 CONFIG_SPL_MTD_SUPPORT
3599 Support for the MTD subsystem within SPL. Useful for
3600 environment on NAND support within SPL.
3601
3602 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3603 Set for the SPL on PPC mpc8xxx targets, support for
3604 drivers/ddr/fsl/libddr.o in SPL binary.
3605
3606 CONFIG_SPL_COMMON_INIT_DDR
3607 Set for common ddr init with serial presence detect in
3608 SPL binary.
3609
3610 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3611 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3612 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3613 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3614 CONFIG_SYS_NAND_ECCBYTES
3615 Defines the size and behavior of the NAND that SPL uses
3616 to read U-Boot
3617
3618 CONFIG_SPL_NAND_BOOT
3619 Add support NAND boot
3620
3621 CONFIG_SYS_NAND_U_BOOT_OFFS
3622 Location in NAND to read U-Boot from
3623
3624 CONFIG_SYS_NAND_U_BOOT_DST
3625 Location in memory to load U-Boot to
3626
3627 CONFIG_SYS_NAND_U_BOOT_SIZE
3628 Size of image to load
3629
3630 CONFIG_SYS_NAND_U_BOOT_START
3631 Entry point in loaded image to jump to
3632
3633 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3634 Define this if you need to first read the OOB and then the
3635 data. This is used for example on davinci plattforms.
3636
3637 CONFIG_SPL_OMAP3_ID_NAND
3638 Support for an OMAP3-specific set of functions to return the
3639 ID and MFR of the first attached NAND chip, if present.
3640
3641 CONFIG_SPL_SERIAL_SUPPORT
3642 Support for drivers/serial/libserial.o in SPL binary
3643
3644 CONFIG_SPL_SPI_FLASH_SUPPORT
3645 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3646
3647 CONFIG_SPL_SPI_SUPPORT
3648 Support for drivers/spi/libspi.o in SPL binary
3649
3650 CONFIG_SPL_RAM_DEVICE
3651 Support for running image already present in ram, in SPL binary
3652
3653 CONFIG_SPL_LIBGENERIC_SUPPORT
3654 Support for lib/libgeneric.o in SPL binary
3655
3656 CONFIG_SPL_ENV_SUPPORT
3657 Support for the environment operating in SPL binary
3658
3659 CONFIG_SPL_NET_SUPPORT
3660 Support for the net/libnet.o in SPL binary.
3661 It conflicts with SPL env from storage medium specified by
3662 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3663
3664 CONFIG_SPL_PAD_TO
3665 Image offset to which the SPL should be padded before appending
3666 the SPL payload. By default, this is defined as
3667 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3668 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3669 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3670
3671 CONFIG_SPL_TARGET
3672 Final target image containing SPL and payload. Some SPLs
3673 use an arch-specific makefile fragment instead, for
3674 example if more than one image needs to be produced.
3675
3676 CONFIG_FIT_SPL_PRINT
3677 Printing information about a FIT image adds quite a bit of
3678 code to SPL. So this is normally disabled in SPL. Use this
3679 option to re-enable it. This will affect the output of the
3680 bootm command when booting a FIT image.
3681
3682 - TPL framework
3683 CONFIG_TPL
3684 Enable building of TPL globally.
3685
3686 CONFIG_TPL_PAD_TO
3687 Image offset to which the TPL should be padded before appending
3688 the TPL payload. By default, this is defined as
3689 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3690 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3691 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3692
3693 Modem Support:
3694 --------------
3695
3696 [so far only for SMDK2400 boards]
3697
3698 - Modem support enable:
3699 CONFIG_MODEM_SUPPORT
3700
3701 - RTS/CTS Flow control enable:
3702 CONFIG_HWFLOW
3703
3704 - Modem debug support:
3705 CONFIG_MODEM_SUPPORT_DEBUG
3706
3707 Enables debugging stuff (char screen[1024], dbg())
3708 for modem support. Useful only with BDI2000.
3709
3710 - Interrupt support (PPC):
3711
3712 There are common interrupt_init() and timer_interrupt()
3713 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3714 for CPU specific initialization. interrupt_init_cpu()
3715 should set decrementer_count to appropriate value. If
3716 CPU resets decrementer automatically after interrupt
3717 (ppc4xx) it should set decrementer_count to zero.
3718 timer_interrupt() calls timer_interrupt_cpu() for CPU
3719 specific handling. If board has watchdog / status_led
3720 / other_activity_monitor it works automatically from
3721 general timer_interrupt().
3722
3723 - General:
3724
3725 In the target system modem support is enabled when a
3726 specific key (key combination) is pressed during
3727 power-on. Otherwise U-Boot will boot normally
3728 (autoboot). The key_pressed() function is called from
3729 board_init(). Currently key_pressed() is a dummy
3730 function, returning 1 and thus enabling modem
3731 initialization.
3732
3733 If there are no modem init strings in the
3734 environment, U-Boot proceed to autoboot; the
3735 previous output (banner, info printfs) will be
3736 suppressed, though.
3737
3738 See also: doc/README.Modem
3739
3740 Board initialization settings:
3741 ------------------------------
3742
3743 During Initialization u-boot calls a number of board specific functions
3744 to allow the preparation of board specific prerequisites, e.g. pin setup
3745 before drivers are initialized. To enable these callbacks the
3746 following configuration macros have to be defined. Currently this is
3747 architecture specific, so please check arch/your_architecture/lib/board.c
3748 typically in board_init_f() and board_init_r().
3749
3750 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3751 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3752 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3753 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3754
3755 Configuration Settings:
3756 -----------------------
3757
3758 - CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
3759 Optionally it can be defined to support 64-bit memory commands.
3760
3761 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3762 undefine this when you're short of memory.
3763
3764 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3765 width of the commands listed in the 'help' command output.
3766
3767 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3768 prompt for user input.
3769
3770 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3771
3772 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3773
3774 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3775
3776 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3777 the application (usually a Linux kernel) when it is
3778 booted
3779
3780 - CONFIG_SYS_BAUDRATE_TABLE:
3781 List of legal baudrate settings for this board.
3782
3783 - CONFIG_SYS_CONSOLE_INFO_QUIET
3784 Suppress display of console information at boot.
3785
3786 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3787 If the board specific function
3788 extern int overwrite_console (void);
3789 returns 1, the stdin, stderr and stdout are switched to the
3790 serial port, else the settings in the environment are used.
3791
3792 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3793 Enable the call to overwrite_console().
3794
3795 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3796 Enable overwrite of previous console environment settings.
3797
3798 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3799 Begin and End addresses of the area used by the
3800 simple memory test.
3801
3802 - CONFIG_SYS_ALT_MEMTEST:
3803 Enable an alternate, more extensive memory test.
3804
3805 - CONFIG_SYS_MEMTEST_SCRATCH:
3806 Scratch address used by the alternate memory test
3807 You only need to set this if address zero isn't writeable
3808
3809 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3810 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3811 this specified memory area will get subtracted from the top
3812 (end) of RAM and won't get "touched" at all by U-Boot. By
3813 fixing up gd->ram_size the Linux kernel should gets passed
3814 the now "corrected" memory size and won't touch it either.
3815 This should work for arch/ppc and arch/powerpc. Only Linux
3816 board ports in arch/powerpc with bootwrapper support that
3817 recalculate the memory size from the SDRAM controller setup
3818 will have to get fixed in Linux additionally.
3819
3820 This option can be used as a workaround for the 440EPx/GRx
3821 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3822 be touched.
3823
3824 WARNING: Please make sure that this value is a multiple of
3825 the Linux page size (normally 4k). If this is not the case,
3826 then the end address of the Linux memory will be located at a
3827 non page size aligned address and this could cause major
3828 problems.
3829
3830 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3831 Enable temporary baudrate change while serial download
3832
3833 - CONFIG_SYS_SDRAM_BASE:
3834 Physical start address of SDRAM. _Must_ be 0 here.
3835
3836 - CONFIG_SYS_MBIO_BASE:
3837 Physical start address of Motherboard I/O (if using a
3838 Cogent motherboard)
3839
3840 - CONFIG_SYS_FLASH_BASE:
3841 Physical start address of Flash memory.
3842
3843 - CONFIG_SYS_MONITOR_BASE:
3844 Physical start address of boot monitor code (set by
3845 make config files to be same as the text base address
3846 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3847 CONFIG_SYS_FLASH_BASE when booting from flash.
3848
3849 - CONFIG_SYS_MONITOR_LEN:
3850 Size of memory reserved for monitor code, used to
3851 determine _at_compile_time_ (!) if the environment is
3852 embedded within the U-Boot image, or in a separate
3853 flash sector.
3854
3855 - CONFIG_SYS_MALLOC_LEN:
3856 Size of DRAM reserved for malloc() use.
3857
3858 - CONFIG_SYS_MALLOC_F_LEN
3859 Size of the malloc() pool for use before relocation. If
3860 this is defined, then a very simple malloc() implementation
3861 will become available before relocation. The address is just
3862 below the global data, and the stack is moved down to make
3863 space.
3864
3865 This feature allocates regions with increasing addresses
3866 within the region. calloc() is supported, but realloc()
3867 is not available. free() is supported but does nothing.
3868 The memory will be freed (or in fact just forgotton) when
3869 U-Boot relocates itself.
3870
3871 Pre-relocation malloc() is only supported on ARM and sandbox
3872 at present but is fairly easy to enable for other archs.
3873
3874 - CONFIG_SYS_BOOTM_LEN:
3875 Normally compressed uImages are limited to an
3876 uncompressed size of 8 MBytes. If this is not enough,
3877 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3878 to adjust this setting to your needs.
3879
3880 - CONFIG_SYS_BOOTMAPSZ:
3881 Maximum size of memory mapped by the startup code of
3882 the Linux kernel; all data that must be processed by
3883 the Linux kernel (bd_info, boot arguments, FDT blob if
3884 used) must be put below this limit, unless "bootm_low"
3885 environment variable is defined and non-zero. In such case
3886 all data for the Linux kernel must be between "bootm_low"
3887 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3888 variable "bootm_mapsize" will override the value of
3889 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3890 then the value in "bootm_size" will be used instead.
3891
3892 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3893 Enable initrd_high functionality. If defined then the
3894 initrd_high feature is enabled and the bootm ramdisk subcommand
3895 is enabled.
3896
3897 - CONFIG_SYS_BOOT_GET_CMDLINE:
3898 Enables allocating and saving kernel cmdline in space between
3899 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3900
3901 - CONFIG_SYS_BOOT_GET_KBD:
3902 Enables allocating and saving a kernel copy of the bd_info in
3903 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3904
3905 - CONFIG_SYS_MAX_FLASH_BANKS:
3906 Max number of Flash memory banks
3907
3908 - CONFIG_SYS_MAX_FLASH_SECT:
3909 Max number of sectors on a Flash chip
3910
3911 - CONFIG_SYS_FLASH_ERASE_TOUT:
3912 Timeout for Flash erase operations (in ms)
3913
3914 - CONFIG_SYS_FLASH_WRITE_TOUT:
3915 Timeout for Flash write operations (in ms)
3916
3917 - CONFIG_SYS_FLASH_LOCK_TOUT
3918 Timeout for Flash set sector lock bit operation (in ms)
3919
3920 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3921 Timeout for Flash clear lock bits operation (in ms)
3922
3923 - CONFIG_SYS_FLASH_PROTECTION
3924 If defined, hardware flash sectors protection is used
3925 instead of U-Boot software protection.
3926
3927 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3928
3929 Enable TFTP transfers directly to flash memory;
3930 without this option such a download has to be
3931 performed in two steps: (1) download to RAM, and (2)
3932 copy from RAM to flash.
3933
3934 The two-step approach is usually more reliable, since
3935 you can check if the download worked before you erase
3936 the flash, but in some situations (when system RAM is
3937 too limited to allow for a temporary copy of the
3938 downloaded image) this option may be very useful.
3939
3940 - CONFIG_SYS_FLASH_CFI:
3941 Define if the flash driver uses extra elements in the
3942 common flash structure for storing flash geometry.
3943
3944 - CONFIG_FLASH_CFI_DRIVER
3945 This option also enables the building of the cfi_flash driver
3946 in the drivers directory
3947
3948 - CONFIG_FLASH_CFI_MTD
3949 This option enables the building of the cfi_mtd driver
3950 in the drivers directory. The driver exports CFI flash
3951 to the MTD layer.
3952
3953 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3954 Use buffered writes to flash.
3955
3956 - CONFIG_FLASH_SPANSION_S29WS_N
3957 s29ws-n MirrorBit flash has non-standard addresses for buffered
3958 write commands.
3959
3960 - CONFIG_SYS_FLASH_QUIET_TEST
3961 If this option is defined, the common CFI flash doesn't
3962 print it's warning upon not recognized FLASH banks. This
3963 is useful, if some of the configured banks are only
3964 optionally available.
3965
3966 - CONFIG_FLASH_SHOW_PROGRESS
3967 If defined (must be an integer), print out countdown
3968 digits and dots. Recommended value: 45 (9..1) for 80
3969 column displays, 15 (3..1) for 40 column displays.
3970
3971 - CONFIG_FLASH_VERIFY
3972 If defined, the content of the flash (destination) is compared
3973 against the source after the write operation. An error message
3974 will be printed when the contents are not identical.
3975 Please note that this option is useless in nearly all cases,
3976 since such flash programming errors usually are detected earlier
3977 while unprotecting/erasing/programming. Please only enable
3978 this option if you really know what you are doing.
3979
3980 - CONFIG_SYS_RX_ETH_BUFFER:
3981 Defines the number of Ethernet receive buffers. On some
3982 Ethernet controllers it is recommended to set this value
3983 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3984 buffers can be full shortly after enabling the interface
3985 on high Ethernet traffic.
3986 Defaults to 4 if not defined.
3987
3988 - CONFIG_ENV_MAX_ENTRIES
3989
3990 Maximum number of entries in the hash table that is used
3991 internally to store the environment settings. The default
3992 setting is supposed to be generous and should work in most
3993 cases. This setting can be used to tune behaviour; see
3994 lib/hashtable.c for details.
3995
3996 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3997 - CONFIG_ENV_FLAGS_LIST_STATIC
3998 Enable validation of the values given to environment variables when
3999 calling env set. Variables can be restricted to only decimal,
4000 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
4001 the variables can also be restricted to IP address or MAC address.
4002
4003 The format of the list is:
4004 type_attribute = [s|d|x|b|i|m]
4005 access_atribute = [a|r|o|c]
4006 attributes = type_attribute[access_atribute]
4007 entry = variable_name[:attributes]
4008 list = entry[,list]
4009
4010 The type attributes are:
4011 s - String (default)
4012 d - Decimal
4013 x - Hexadecimal
4014 b - Boolean ([1yYtT|0nNfF])
4015 i - IP address
4016 m - MAC address
4017
4018 The access attributes are:
4019 a - Any (default)
4020 r - Read-only
4021 o - Write-once
4022 c - Change-default
4023
4024 - CONFIG_ENV_FLAGS_LIST_DEFAULT
4025 Define this to a list (string) to define the ".flags"
4026 envirnoment variable in the default or embedded environment.
4027
4028 - CONFIG_ENV_FLAGS_LIST_STATIC
4029 Define this to a list (string) to define validation that
4030 should be done if an entry is not found in the ".flags"
4031 environment variable. To override a setting in the static
4032 list, simply add an entry for the same variable name to the
4033 ".flags" variable.
4034
4035 - CONFIG_ENV_ACCESS_IGNORE_FORCE
4036 If defined, don't allow the -f switch to env set override variable
4037 access flags.
4038
4039 - CONFIG_SYS_GENERIC_BOARD
4040 This selects the architecture-generic board system instead of the
4041 architecture-specific board files. It is intended to move boards
4042 to this new framework over time. Defining this will disable the
4043 arch/foo/lib/board.c file and use common/board_f.c and
4044 common/board_r.c instead. To use this option your architecture
4045 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
4046 its config.mk file). If you find problems enabling this option on
4047 your board please report the problem and send patches!
4048
4049 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
4050 This is set by OMAP boards for the max time that reset should
4051 be asserted. See doc/README.omap-reset-time for details on how
4052 the value can be calulated on a given board.
4053
4054 The following definitions that deal with the placement and management
4055 of environment data (variable area); in general, we support the
4056 following configurations:
4057
4058 - CONFIG_BUILD_ENVCRC:
4059
4060 Builds up envcrc with the target environment so that external utils
4061 may easily extract it and embed it in final U-Boot images.
4062
4063 - CONFIG_ENV_IS_IN_FLASH:
4064
4065 Define this if the environment is in flash memory.
4066
4067 a) The environment occupies one whole flash sector, which is
4068 "embedded" in the text segment with the U-Boot code. This
4069 happens usually with "bottom boot sector" or "top boot
4070 sector" type flash chips, which have several smaller
4071 sectors at the start or the end. For instance, such a
4072 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
4073 such a case you would place the environment in one of the
4074 4 kB sectors - with U-Boot code before and after it. With
4075 "top boot sector" type flash chips, you would put the
4076 environment in one of the last sectors, leaving a gap
4077 between U-Boot and the environment.
4078
4079 - CONFIG_ENV_OFFSET:
4080
4081 Offset of environment data (variable area) to the
4082 beginning of flash memory; for instance, with bottom boot
4083 type flash chips the second sector can be used: the offset
4084 for this sector is given here.
4085
4086 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
4087
4088 - CONFIG_ENV_ADDR:
4089
4090 This is just another way to specify the start address of
4091 the flash sector containing the environment (instead of
4092 CONFIG_ENV_OFFSET).
4093
4094 - CONFIG_ENV_SECT_SIZE:
4095
4096 Size of the sector containing the environment.
4097
4098
4099 b) Sometimes flash chips have few, equal sized, BIG sectors.
4100 In such a case you don't want to spend a whole sector for
4101 the environment.
4102
4103 - CONFIG_ENV_SIZE:
4104
4105 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
4106 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
4107 of this flash sector for the environment. This saves
4108 memory for the RAM copy of the environment.
4109
4110 It may also save flash memory if you decide to use this
4111 when your environment is "embedded" within U-Boot code,
4112 since then the remainder of the flash sector could be used
4113 for U-Boot code. It should be pointed out that this is
4114 STRONGLY DISCOURAGED from a robustness point of view:
4115 updating the environment in flash makes it always
4116 necessary to erase the WHOLE sector. If something goes
4117 wrong before the contents has been restored from a copy in
4118 RAM, your target system will be dead.
4119
4120 - CONFIG_ENV_ADDR_REDUND
4121 CONFIG_ENV_SIZE_REDUND
4122
4123 These settings describe a second storage area used to hold
4124 a redundant copy of the environment data, so that there is
4125 a valid backup copy in case there is a power failure during
4126 a "saveenv" operation.
4127
4128 BE CAREFUL! Any changes to the flash layout, and some changes to the
4129 source code will make it necessary to adapt <board>/u-boot.lds*
4130 accordingly!
4131
4132
4133 - CONFIG_ENV_IS_IN_NVRAM:
4134
4135 Define this if you have some non-volatile memory device
4136 (NVRAM, battery buffered SRAM) which you want to use for the
4137 environment.
4138
4139 - CONFIG_ENV_ADDR:
4140 - CONFIG_ENV_SIZE:
4141
4142 These two #defines are used to determine the memory area you
4143 want to use for environment. It is assumed that this memory
4144 can just be read and written to, without any special
4145 provision.
4146
4147 BE CAREFUL! The first access to the environment happens quite early
4148 in U-Boot initalization (when we try to get the setting of for the
4149 console baudrate). You *MUST* have mapped your NVRAM area then, or
4150 U-Boot will hang.
4151
4152 Please note that even with NVRAM we still use a copy of the
4153 environment in RAM: we could work on NVRAM directly, but we want to
4154 keep settings there always unmodified except somebody uses "saveenv"
4155 to save the current settings.
4156
4157
4158 - CONFIG_ENV_IS_IN_EEPROM:
4159
4160 Use this if you have an EEPROM or similar serial access
4161 device and a driver for it.
4162
4163 - CONFIG_ENV_OFFSET:
4164 - CONFIG_ENV_SIZE:
4165
4166 These two #defines specify the offset and size of the
4167 environment area within the total memory of your EEPROM.
4168
4169 - CONFIG_SYS_I2C_EEPROM_ADDR:
4170 If defined, specified the chip address of the EEPROM device.
4171 The default address is zero.
4172
4173 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
4174 If defined, the number of bits used to address bytes in a
4175 single page in the EEPROM device. A 64 byte page, for example
4176 would require six bits.
4177
4178 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
4179 If defined, the number of milliseconds to delay between
4180 page writes. The default is zero milliseconds.
4181
4182 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
4183 The length in bytes of the EEPROM memory array address. Note
4184 that this is NOT the chip address length!
4185
4186 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
4187 EEPROM chips that implement "address overflow" are ones
4188 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
4189 address and the extra bits end up in the "chip address" bit
4190 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
4191 byte chips.
4192
4193 Note that we consider the length of the address field to
4194 still be one byte because the extra address bits are hidden
4195 in the chip address.
4196
4197 - CONFIG_SYS_EEPROM_SIZE:
4198 The size in bytes of the EEPROM device.
4199
4200 - CONFIG_ENV_EEPROM_IS_ON_I2C
4201 define this, if you have I2C and SPI activated, and your
4202 EEPROM, which holds the environment, is on the I2C bus.
4203
4204 - CONFIG_I2C_ENV_EEPROM_BUS
4205 if you have an Environment on an EEPROM reached over
4206 I2C muxes, you can define here, how to reach this
4207 EEPROM. For example:
4208
4209 #define CONFIG_I2C_ENV_EEPROM_BUS 1
4210
4211 EEPROM which holds the environment, is reached over
4212 a pca9547 i2c mux with address 0x70, channel 3.
4213
4214 - CONFIG_ENV_IS_IN_DATAFLASH:
4215
4216 Define this if you have a DataFlash memory device which you
4217 want to use for the environment.
4218
4219 - CONFIG_ENV_OFFSET:
4220 - CONFIG_ENV_ADDR:
4221 - CONFIG_ENV_SIZE:
4222
4223 These three #defines specify the offset and size of the
4224 environment area within the total memory of your DataFlash placed
4225 at the specified address.
4226
4227 - CONFIG_ENV_IS_IN_SPI_FLASH:
4228
4229 Define this if you have a SPI Flash memory device which you
4230 want to use for the environment.
4231
4232 - CONFIG_ENV_OFFSET:
4233 - CONFIG_ENV_SIZE:
4234
4235 These two #defines specify the offset and size of the
4236 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
4237 aligned to an erase sector boundary.
4238
4239 - CONFIG_ENV_SECT_SIZE:
4240
4241 Define the SPI flash's sector size.
4242
4243 - CONFIG_ENV_OFFSET_REDUND (optional):
4244
4245 This setting describes a second storage area of CONFIG_ENV_SIZE
4246 size used to hold a redundant copy of the environment data, so
4247 that there is a valid backup copy in case there is a power failure
4248 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4249 aligned to an erase sector boundary.
4250
4251 - CONFIG_ENV_SPI_BUS (optional):
4252 - CONFIG_ENV_SPI_CS (optional):
4253
4254 Define the SPI bus and chip select. If not defined they will be 0.
4255
4256 - CONFIG_ENV_SPI_MAX_HZ (optional):
4257
4258 Define the SPI max work clock. If not defined then use 1MHz.
4259
4260 - CONFIG_ENV_SPI_MODE (optional):
4261
4262 Define the SPI work mode. If not defined then use SPI_MODE_3.
4263
4264 - CONFIG_ENV_IS_IN_REMOTE:
4265
4266 Define this if you have a remote memory space which you
4267 want to use for the local device's environment.
4268
4269 - CONFIG_ENV_ADDR:
4270 - CONFIG_ENV_SIZE:
4271
4272 These two #defines specify the address and size of the
4273 environment area within the remote memory space. The
4274 local device can get the environment from remote memory
4275 space by SRIO or PCIE links.
4276
4277 BE CAREFUL! For some special cases, the local device can not use
4278 "saveenv" command. For example, the local device will get the
4279 environment stored in a remote NOR flash by SRIO or PCIE link,
4280 but it can not erase, write this NOR flash by SRIO or PCIE interface.
4281
4282 - CONFIG_ENV_IS_IN_NAND:
4283
4284 Define this if you have a NAND device which you want to use
4285 for the environment.
4286
4287 - CONFIG_ENV_OFFSET:
4288 - CONFIG_ENV_SIZE:
4289
4290 These two #defines specify the offset and size of the environment
4291 area within the first NAND device. CONFIG_ENV_OFFSET must be
4292 aligned to an erase block boundary.
4293
4294 - CONFIG_ENV_OFFSET_REDUND (optional):
4295
4296 This setting describes a second storage area of CONFIG_ENV_SIZE
4297 size used to hold a redundant copy of the environment data, so
4298 that there is a valid backup copy in case there is a power failure
4299 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4300 aligned to an erase block boundary.
4301
4302 - CONFIG_ENV_RANGE (optional):
4303
4304 Specifies the length of the region in which the environment
4305 can be written. This should be a multiple of the NAND device's
4306 block size. Specifying a range with more erase blocks than
4307 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
4308 the range to be avoided.
4309
4310 - CONFIG_ENV_OFFSET_OOB (optional):
4311
4312 Enables support for dynamically retrieving the offset of the
4313 environment from block zero's out-of-band data. The
4314 "nand env.oob" command can be used to record this offset.
4315 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
4316 using CONFIG_ENV_OFFSET_OOB.
4317
4318 - CONFIG_NAND_ENV_DST
4319
4320 Defines address in RAM to which the nand_spl code should copy the
4321 environment. If redundant environment is used, it will be copied to
4322 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
4323
4324 - CONFIG_ENV_IS_IN_UBI:
4325
4326 Define this if you have an UBI volume that you want to use for the
4327 environment. This has the benefit of wear-leveling the environment
4328 accesses, which is important on NAND.
4329
4330 - CONFIG_ENV_UBI_PART:
4331
4332 Define this to a string that is the mtd partition containing the UBI.
4333
4334 - CONFIG_ENV_UBI_VOLUME:
4335
4336 Define this to the name of the volume that you want to store the
4337 environment in.
4338
4339 - CONFIG_ENV_UBI_VOLUME_REDUND:
4340
4341 Define this to the name of another volume to store a second copy of
4342 the environment in. This will enable redundant environments in UBI.
4343 It is assumed that both volumes are in the same MTD partition.
4344
4345 - CONFIG_UBI_SILENCE_MSG
4346 - CONFIG_UBIFS_SILENCE_MSG
4347
4348 You will probably want to define these to avoid a really noisy system
4349 when storing the env in UBI.
4350
4351 - CONFIG_ENV_IS_IN_FAT:
4352 Define this if you want to use the FAT file system for the environment.
4353
4354 - FAT_ENV_INTERFACE:
4355
4356 Define this to a string that is the name of the block device.
4357
4358 - FAT_ENV_DEV_AND_PART:
4359
4360 Define this to a string to specify the partition of the device. It can
4361 be as following:
4362
4363 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
4364 - "D:P": device D partition P. Error occurs if device D has no
4365 partition table.
4366 - "D:0": device D.
4367 - "D" or "D:": device D partition 1 if device D has partition
4368 table, or the whole device D if has no partition
4369 table.
4370 - "D:auto": first partition in device D with bootable flag set.
4371 If none, first valid paratition in device D. If no
4372 partition table then means device D.
4373
4374 - FAT_ENV_FILE:
4375
4376 It's a string of the FAT file name. This file use to store the
4377 envrionment.
4378
4379 - CONFIG_FAT_WRITE:
4380 This should be defined. Otherwise it cannot save the envrionment file.
4381
4382 - CONFIG_ENV_IS_IN_MMC:
4383
4384 Define this if you have an MMC device which you want to use for the
4385 environment.
4386
4387 - CONFIG_SYS_MMC_ENV_DEV:
4388
4389 Specifies which MMC device the environment is stored in.
4390
4391 - CONFIG_SYS_MMC_ENV_PART (optional):
4392
4393 Specifies which MMC partition the environment is stored in. If not
4394 set, defaults to partition 0, the user area. Common values might be
4395 1 (first MMC boot partition), 2 (second MMC boot partition).
4396
4397 - CONFIG_ENV_OFFSET:
4398 - CONFIG_ENV_SIZE:
4399
4400 These two #defines specify the offset and size of the environment
4401 area within the specified MMC device.
4402
4403 If offset is positive (the usual case), it is treated as relative to
4404 the start of the MMC partition. If offset is negative, it is treated
4405 as relative to the end of the MMC partition. This can be useful if
4406 your board may be fitted with different MMC devices, which have
4407 different sizes for the MMC partitions, and you always want the
4408 environment placed at the very end of the partition, to leave the
4409 maximum possible space before it, to store other data.
4410
4411 These two values are in units of bytes, but must be aligned to an
4412 MMC sector boundary.
4413
4414 - CONFIG_ENV_OFFSET_REDUND (optional):
4415
4416 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
4417 hold a redundant copy of the environment data. This provides a
4418 valid backup copy in case the other copy is corrupted, e.g. due
4419 to a power failure during a "saveenv" operation.
4420
4421 This value may also be positive or negative; this is handled in the
4422 same way as CONFIG_ENV_OFFSET.
4423
4424 This value is also in units of bytes, but must also be aligned to
4425 an MMC sector boundary.
4426
4427 - CONFIG_ENV_SIZE_REDUND (optional):
4428
4429 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
4430 set. If this value is set, it must be set to the same value as
4431 CONFIG_ENV_SIZE.
4432
4433 - CONFIG_SYS_SPI_INIT_OFFSET
4434
4435 Defines offset to the initial SPI buffer area in DPRAM. The
4436 area is used at an early stage (ROM part) if the environment
4437 is configured to reside in the SPI EEPROM: We need a 520 byte
4438 scratch DPRAM area. It is used between the two initialization
4439 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
4440 to be a good choice since it makes it far enough from the
4441 start of the data area as well as from the stack pointer.
4442
4443 Please note that the environment is read-only until the monitor
4444 has been relocated to RAM and a RAM copy of the environment has been
4445 created; also, when using EEPROM you will have to use getenv_f()
4446 until then to read environment variables.
4447
4448 The environment is protected by a CRC32 checksum. Before the monitor
4449 is relocated into RAM, as a result of a bad CRC you will be working
4450 with the compiled-in default environment - *silently*!!! [This is
4451 necessary, because the first environment variable we need is the
4452 "baudrate" setting for the console - if we have a bad CRC, we don't
4453 have any device yet where we could complain.]
4454
4455 Note: once the monitor has been relocated, then it will complain if
4456 the default environment is used; a new CRC is computed as soon as you
4457 use the "saveenv" command to store a valid environment.
4458
4459 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
4460 Echo the inverted Ethernet link state to the fault LED.
4461
4462 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
4463 also needs to be defined.
4464
4465 - CONFIG_SYS_FAULT_MII_ADDR:
4466 MII address of the PHY to check for the Ethernet link state.
4467
4468 - CONFIG_NS16550_MIN_FUNCTIONS:
4469 Define this if you desire to only have use of the NS16550_init
4470 and NS16550_putc functions for the serial driver located at
4471 drivers/serial/ns16550.c. This option is useful for saving
4472 space for already greatly restricted images, including but not
4473 limited to NAND_SPL configurations.
4474
4475 - CONFIG_DISPLAY_BOARDINFO
4476 Display information about the board that U-Boot is running on
4477 when U-Boot starts up. The board function checkboard() is called
4478 to do this.
4479
4480 - CONFIG_DISPLAY_BOARDINFO_LATE
4481 Similar to the previous option, but display this information
4482 later, once stdio is running and output goes to the LCD, if
4483 present.
4484
4485 - CONFIG_BOARD_SIZE_LIMIT:
4486 Maximum size of the U-Boot image. When defined, the
4487 build system checks that the actual size does not
4488 exceed it.
4489
4490 Low Level (hardware related) configuration options:
4491 ---------------------------------------------------
4492
4493 - CONFIG_SYS_CACHELINE_SIZE:
4494 Cache Line Size of the CPU.
4495
4496 - CONFIG_SYS_DEFAULT_IMMR:
4497 Default address of the IMMR after system reset.
4498
4499 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
4500 and RPXsuper) to be able to adjust the position of
4501 the IMMR register after a reset.
4502
4503 - CONFIG_SYS_CCSRBAR_DEFAULT:
4504 Default (power-on reset) physical address of CCSR on Freescale
4505 PowerPC SOCs.
4506
4507 - CONFIG_SYS_CCSRBAR:
4508 Virtual address of CCSR. On a 32-bit build, this is typically
4509 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
4510
4511 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
4512 for cross-platform code that uses that macro instead.
4513
4514 - CONFIG_SYS_CCSRBAR_PHYS:
4515 Physical address of CCSR. CCSR can be relocated to a new
4516 physical address, if desired. In this case, this macro should
4517 be set to that address. Otherwise, it should be set to the
4518 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
4519 is typically relocated on 36-bit builds. It is recommended
4520 that this macro be defined via the _HIGH and _LOW macros:
4521
4522 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
4523 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
4524
4525 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4526 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
4527 either 0 (32-bit build) or 0xF (36-bit build). This macro is
4528 used in assembly code, so it must not contain typecasts or
4529 integer size suffixes (e.g. "ULL").
4530
4531 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
4532 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
4533 used in assembly code, so it must not contain typecasts or
4534 integer size suffixes (e.g. "ULL").
4535
4536 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
4537 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
4538 forced to a value that ensures that CCSR is not relocated.
4539
4540 - Floppy Disk Support:
4541 CONFIG_SYS_FDC_DRIVE_NUMBER
4542
4543 the default drive number (default value 0)
4544
4545 CONFIG_SYS_ISA_IO_STRIDE
4546
4547 defines the spacing between FDC chipset registers
4548 (default value 1)
4549
4550 CONFIG_SYS_ISA_IO_OFFSET
4551
4552 defines the offset of register from address. It
4553 depends on which part of the data bus is connected to
4554 the FDC chipset. (default value 0)
4555
4556 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4557 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
4558 default value.
4559
4560 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
4561 fdc_hw_init() is called at the beginning of the FDC
4562 setup. fdc_hw_init() must be provided by the board
4563 source code. It is used to make hardware dependant
4564 initializations.
4565
4566 - CONFIG_IDE_AHB:
4567 Most IDE controllers were designed to be connected with PCI
4568 interface. Only few of them were designed for AHB interface.
4569 When software is doing ATA command and data transfer to
4570 IDE devices through IDE-AHB controller, some additional
4571 registers accessing to these kind of IDE-AHB controller
4572 is requierd.
4573
4574 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4575 DO NOT CHANGE unless you know exactly what you're
4576 doing! (11-4) [MPC8xx/82xx systems only]
4577
4578 - CONFIG_SYS_INIT_RAM_ADDR:
4579
4580 Start address of memory area that can be used for
4581 initial data and stack; please note that this must be
4582 writable memory that is working WITHOUT special
4583 initialization, i. e. you CANNOT use normal RAM which
4584 will become available only after programming the
4585 memory controller and running certain initialization
4586 sequences.
4587
4588 U-Boot uses the following memory types:
4589 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4590 - MPC824X: data cache
4591 - PPC4xx: data cache
4592
4593 - CONFIG_SYS_GBL_DATA_OFFSET:
4594
4595 Offset of the initial data structure in the memory
4596 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4597 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4598 data is located at the end of the available space
4599 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4600 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4601 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4602 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4603
4604 Note:
4605 On the MPC824X (or other systems that use the data
4606 cache for initial memory) the address chosen for
4607 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4608 point to an otherwise UNUSED address space between
4609 the top of RAM and the start of the PCI space.
4610
4611 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4612
4613 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4614
4615 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4616
4617 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4618
4619 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4620
4621 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4622
4623 - CONFIG_SYS_OR_TIMING_SDRAM:
4624 SDRAM timing
4625
4626 - CONFIG_SYS_MAMR_PTA:
4627 periodic timer for refresh
4628
4629 - CONFIG_SYS_DER: Debug Event Register (37-47)
4630
4631 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4632 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4633 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4634 CONFIG_SYS_BR1_PRELIM:
4635 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4636
4637 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4638 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4639 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4640 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4641
4642 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4643 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4644 Machine Mode Register and Memory Periodic Timer
4645 Prescaler definitions (SDRAM timing)
4646
4647 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4648 enable I2C microcode relocation patch (MPC8xx);
4649 define relocation offset in DPRAM [DSP2]
4650
4651 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4652 enable SMC microcode relocation patch (MPC8xx);
4653 define relocation offset in DPRAM [SMC1]
4654
4655 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4656 enable SPI microcode relocation patch (MPC8xx);
4657 define relocation offset in DPRAM [SCC4]
4658
4659 - CONFIG_SYS_USE_OSCCLK:
4660 Use OSCM clock mode on MBX8xx board. Be careful,
4661 wrong setting might damage your board. Read
4662 doc/README.MBX before setting this variable!
4663
4664 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4665 Offset of the bootmode word in DPRAM used by post
4666 (Power On Self Tests). This definition overrides
4667 #define'd default value in commproc.h resp.
4668 cpm_8260.h.
4669
4670 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4671 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4672 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4673 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4674 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4675 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4676 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4677 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4678 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4679
4680 - CONFIG_PCI_DISABLE_PCIE:
4681 Disable PCI-Express on systems where it is supported but not
4682 required.
4683
4684 - CONFIG_PCI_ENUM_ONLY
4685 Only scan through and get the devices on the busses.
4686 Don't do any setup work, presumably because someone or
4687 something has already done it, and we don't need to do it
4688 a second time. Useful for platforms that are pre-booted
4689 by coreboot or similar.
4690
4691 - CONFIG_PCI_INDIRECT_BRIDGE:
4692 Enable support for indirect PCI bridges.
4693
4694 - CONFIG_SYS_SRIO:
4695 Chip has SRIO or not
4696
4697 - CONFIG_SRIO1:
4698 Board has SRIO 1 port available
4699
4700 - CONFIG_SRIO2:
4701 Board has SRIO 2 port available
4702
4703 - CONFIG_SRIO_PCIE_BOOT_MASTER
4704 Board can support master function for Boot from SRIO and PCIE
4705
4706 - CONFIG_SYS_SRIOn_MEM_VIRT:
4707 Virtual Address of SRIO port 'n' memory region
4708
4709 - CONFIG_SYS_SRIOn_MEM_PHYS:
4710 Physical Address of SRIO port 'n' memory region
4711
4712 - CONFIG_SYS_SRIOn_MEM_SIZE:
4713 Size of SRIO port 'n' memory region
4714
4715 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4716 Defined to tell the NAND controller that the NAND chip is using
4717 a 16 bit bus.
4718 Not all NAND drivers use this symbol.
4719 Example of drivers that use it:
4720 - drivers/mtd/nand/ndfc.c
4721 - drivers/mtd/nand/mxc_nand.c
4722
4723 - CONFIG_SYS_NDFC_EBC0_CFG
4724 Sets the EBC0_CFG register for the NDFC. If not defined
4725 a default value will be used.
4726
4727 - CONFIG_SPD_EEPROM
4728 Get DDR timing information from an I2C EEPROM. Common
4729 with pluggable memory modules such as SODIMMs
4730
4731 SPD_EEPROM_ADDRESS
4732 I2C address of the SPD EEPROM
4733
4734 - CONFIG_SYS_SPD_BUS_NUM
4735 If SPD EEPROM is on an I2C bus other than the first
4736 one, specify here. Note that the value must resolve
4737 to something your driver can deal with.
4738
4739 - CONFIG_SYS_DDR_RAW_TIMING
4740 Get DDR timing information from other than SPD. Common with
4741 soldered DDR chips onboard without SPD. DDR raw timing
4742 parameters are extracted from datasheet and hard-coded into
4743 header files or board specific files.
4744
4745 - CONFIG_FSL_DDR_INTERACTIVE
4746 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4747
4748 - CONFIG_SYS_83XX_DDR_USES_CS0
4749 Only for 83xx systems. If specified, then DDR should
4750 be configured using CS0 and CS1 instead of CS2 and CS3.
4751
4752 - CONFIG_ETHER_ON_FEC[12]
4753 Define to enable FEC[12] on a 8xx series processor.
4754
4755 - CONFIG_FEC[12]_PHY
4756 Define to the hardcoded PHY address which corresponds
4757 to the given FEC; i. e.
4758 #define CONFIG_FEC1_PHY 4
4759 means that the PHY with address 4 is connected to FEC1
4760
4761 When set to -1, means to probe for first available.
4762
4763 - CONFIG_FEC[12]_PHY_NORXERR
4764 The PHY does not have a RXERR line (RMII only).
4765 (so program the FEC to ignore it).
4766
4767 - CONFIG_RMII
4768 Enable RMII mode for all FECs.
4769 Note that this is a global option, we can't
4770 have one FEC in standard MII mode and another in RMII mode.
4771
4772 - CONFIG_CRC32_VERIFY
4773 Add a verify option to the crc32 command.
4774 The syntax is:
4775
4776 => crc32 -v <address> <count> <crc32>
4777
4778 Where address/count indicate a memory area
4779 and crc32 is the correct crc32 which the
4780 area should have.
4781
4782 - CONFIG_LOOPW
4783 Add the "loopw" memory command. This only takes effect if
4784 the memory commands are activated globally (CONFIG_CMD_MEM).
4785
4786 - CONFIG_MX_CYCLIC
4787 Add the "mdc" and "mwc" memory commands. These are cyclic
4788 "md/mw" commands.
4789 Examples:
4790
4791 => mdc.b 10 4 500
4792 This command will print 4 bytes (10,11,12,13) each 500 ms.
4793
4794 => mwc.l 100 12345678 10
4795 This command will write 12345678 to address 100 all 10 ms.
4796
4797 This only takes effect if the memory commands are activated
4798 globally (CONFIG_CMD_MEM).
4799
4800 - CONFIG_SKIP_LOWLEVEL_INIT
4801 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4802 low level initializations (like setting up the memory
4803 controller) are omitted and/or U-Boot does not
4804 relocate itself into RAM.
4805
4806 Normally this variable MUST NOT be defined. The only
4807 exception is when U-Boot is loaded (to RAM) by some
4808 other boot loader or by a debugger which performs
4809 these initializations itself.
4810
4811 - CONFIG_SPL_BUILD
4812 Modifies the behaviour of start.S when compiling a loader
4813 that is executed before the actual U-Boot. E.g. when
4814 compiling a NAND SPL.
4815
4816 - CONFIG_TPL_BUILD
4817 Modifies the behaviour of start.S when compiling a loader
4818 that is executed after the SPL and before the actual U-Boot.
4819 It is loaded by the SPL.
4820
4821 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4822 Only for 85xx systems. If this variable is specified, the section
4823 .resetvec is not kept and the section .bootpg is placed in the
4824 previous 4k of the .text section.
4825
4826 - CONFIG_ARCH_MAP_SYSMEM
4827 Generally U-Boot (and in particular the md command) uses
4828 effective address. It is therefore not necessary to regard
4829 U-Boot address as virtual addresses that need to be translated
4830 to physical addresses. However, sandbox requires this, since
4831 it maintains its own little RAM buffer which contains all
4832 addressable memory. This option causes some memory accesses
4833 to be mapped through map_sysmem() / unmap_sysmem().
4834
4835 - CONFIG_USE_ARCH_MEMCPY
4836 CONFIG_USE_ARCH_MEMSET
4837 If these options are used a optimized version of memcpy/memset will
4838 be used if available. These functions may be faster under some
4839 conditions but may increase the binary size.
4840
4841 - CONFIG_X86_RESET_VECTOR
4842 If defined, the x86 reset vector code is included. This is not
4843 needed when U-Boot is running from Coreboot.
4844
4845 - CONFIG_SYS_MPUCLK
4846 Defines the MPU clock speed (in MHz).
4847
4848 NOTE : currently only supported on AM335x platforms.
4849
4850 - CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
4851 Enables the RTC32K OSC on AM33xx based plattforms
4852
4853 - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
4854 Option to disable subpage write in NAND driver
4855 driver that uses this:
4856 drivers/mtd/nand/davinci_nand.c
4857
4858 Freescale QE/FMAN Firmware Support:
4859 -----------------------------------
4860
4861 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4862 loading of "firmware", which is encoded in the QE firmware binary format.
4863 This firmware often needs to be loaded during U-Boot booting, so macros
4864 are used to identify the storage device (NOR flash, SPI, etc) and the address
4865 within that device.
4866
4867 - CONFIG_SYS_FMAN_FW_ADDR
4868 The address in the storage device where the FMAN microcode is located. The
4869 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4870 is also specified.
4871
4872 - CONFIG_SYS_QE_FW_ADDR
4873 The address in the storage device where the QE microcode is located. The
4874 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4875 is also specified.
4876
4877 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4878 The maximum possible size of the firmware. The firmware binary format
4879 has a field that specifies the actual size of the firmware, but it
4880 might not be possible to read any part of the firmware unless some
4881 local storage is allocated to hold the entire firmware first.
4882
4883 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4884 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4885 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4886 virtual address in NOR flash.
4887
4888 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4889 Specifies that QE/FMAN firmware is located in NAND flash.
4890 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4891
4892 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4893 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4894 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4895
4896 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4897 Specifies that QE/FMAN firmware is located on the primary SPI
4898 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4899
4900 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4901 Specifies that QE/FMAN firmware is located in the remote (master)
4902 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4903 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4904 window->master inbound window->master LAW->the ucode address in
4905 master's memory space.
4906
4907 Freescale Layerscape Management Complex Firmware Support:
4908 ---------------------------------------------------------
4909 The Freescale Layerscape Management Complex (MC) supports the loading of
4910 "firmware".
4911 This firmware often needs to be loaded during U-Boot booting, so macros
4912 are used to identify the storage device (NOR flash, SPI, etc) and the address
4913 within that device.
4914
4915 - CONFIG_FSL_MC_ENET
4916 Enable the MC driver for Layerscape SoCs.
4917
4918 - CONFIG_SYS_LS_MC_FW_ADDR
4919 The address in the storage device where the firmware is located. The
4920 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro
4921 is also specified.
4922
4923 - CONFIG_SYS_LS_MC_FW_LENGTH
4924 The maximum possible size of the firmware. The firmware binary format
4925 has a field that specifies the actual size of the firmware, but it
4926 might not be possible to read any part of the firmware unless some
4927 local storage is allocated to hold the entire firmware first.
4928
4929 - CONFIG_SYS_LS_MC_FW_IN_NOR
4930 Specifies that MC firmware is located in NOR flash, mapped as
4931 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
4932 virtual address in NOR flash.
4933
4934 Building the Software:
4935 ======================
4936
4937 Building U-Boot has been tested in several native build environments
4938 and in many different cross environments. Of course we cannot support
4939 all possibly existing versions of cross development tools in all
4940 (potentially obsolete) versions. In case of tool chain problems we
4941 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4942 which is extensively used to build and test U-Boot.
4943
4944 If you are not using a native environment, it is assumed that you
4945 have GNU cross compiling tools available in your path. In this case,
4946 you must set the environment variable CROSS_COMPILE in your shell.
4947 Note that no changes to the Makefile or any other source files are
4948 necessary. For example using the ELDK on a 4xx CPU, please enter:
4949
4950 $ CROSS_COMPILE=ppc_4xx-
4951 $ export CROSS_COMPILE
4952
4953 Note: If you wish to generate Windows versions of the utilities in
4954 the tools directory you can use the MinGW toolchain
4955 (http://www.mingw.org). Set your HOST tools to the MinGW
4956 toolchain and execute 'make tools'. For example:
4957
4958 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4959
4960 Binaries such as tools/mkimage.exe will be created which can
4961 be executed on computers running Windows.
4962
4963 U-Boot is intended to be simple to build. After installing the
4964 sources you must configure U-Boot for one specific board type. This
4965 is done by typing:
4966
4967 make NAME_defconfig
4968
4969 where "NAME_defconfig" is the name of one of the existing configu-
4970 rations; see boards.cfg for supported names.
4971
4972 Note: for some board special configuration names may exist; check if
4973 additional information is available from the board vendor; for
4974 instance, the TQM823L systems are available without (standard)
4975 or with LCD support. You can select such additional "features"
4976 when choosing the configuration, i. e.
4977
4978 make TQM823L_defconfig
4979 - will configure for a plain TQM823L, i. e. no LCD support
4980
4981 make TQM823L_LCD_defconfig
4982 - will configure for a TQM823L with U-Boot console on LCD
4983
4984 etc.
4985
4986
4987 Finally, type "make all", and you should get some working U-Boot
4988 images ready for download to / installation on your system:
4989
4990 - "u-boot.bin" is a raw binary image
4991 - "u-boot" is an image in ELF binary format
4992 - "u-boot.srec" is in Motorola S-Record format
4993
4994 By default the build is performed locally and the objects are saved
4995 in the source directory. One of the two methods can be used to change
4996 this behavior and build U-Boot to some external directory:
4997
4998 1. Add O= to the make command line invocations:
4999
5000 make O=/tmp/build distclean
5001 make O=/tmp/build NAME_defconfig
5002 make O=/tmp/build all
5003
5004 2. Set environment variable BUILD_DIR to point to the desired location:
5005
5006 export BUILD_DIR=/tmp/build
5007 make distclean
5008 make NAME_defconfig
5009 make all
5010
5011 Note that the command line "O=" setting overrides the BUILD_DIR environment
5012 variable.
5013
5014
5015 Please be aware that the Makefiles assume you are using GNU make, so
5016 for instance on NetBSD you might need to use "gmake" instead of
5017 native "make".
5018
5019
5020 If the system board that you have is not listed, then you will need
5021 to port U-Boot to your hardware platform. To do this, follow these
5022 steps:
5023
5024 1. Add a new configuration option for your board to the toplevel
5025 "boards.cfg" file, using the existing entries as examples.
5026 Follow the instructions there to keep the boards in order.
5027 2. Create a new directory to hold your board specific code. Add any
5028 files you need. In your board directory, you will need at least
5029 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
5030 3. Create a new configuration file "include/configs/<board>.h" for
5031 your board
5032 3. If you're porting U-Boot to a new CPU, then also create a new
5033 directory to hold your CPU specific code. Add any files you need.
5034 4. Run "make <board>_defconfig" with your new name.
5035 5. Type "make", and you should get a working "u-boot.srec" file
5036 to be installed on your target system.
5037 6. Debug and solve any problems that might arise.
5038 [Of course, this last step is much harder than it sounds.]
5039
5040
5041 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
5042 ==============================================================
5043
5044 If you have modified U-Boot sources (for instance added a new board
5045 or support for new devices, a new CPU, etc.) you are expected to
5046 provide feedback to the other developers. The feedback normally takes
5047 the form of a "patch", i. e. a context diff against a certain (latest
5048 official or latest in the git repository) version of U-Boot sources.
5049
5050 But before you submit such a patch, please verify that your modifi-
5051 cation did not break existing code. At least make sure that *ALL* of
5052 the supported boards compile WITHOUT ANY compiler warnings. To do so,
5053 just run the "MAKEALL" script, which will configure and build U-Boot
5054 for ALL supported system. Be warned, this will take a while. You can
5055 select which (cross) compiler to use by passing a `CROSS_COMPILE'
5056 environment variable to the script, i. e. to use the ELDK cross tools
5057 you can type
5058
5059 CROSS_COMPILE=ppc_8xx- MAKEALL
5060
5061 or to build on a native PowerPC system you can type
5062
5063 CROSS_COMPILE=' ' MAKEALL
5064
5065 When using the MAKEALL script, the default behaviour is to build
5066 U-Boot in the source directory. This location can be changed by
5067 setting the BUILD_DIR environment variable. Also, for each target
5068 built, the MAKEALL script saves two log files (<target>.ERR and
5069 <target>.MAKEALL) in the <source dir>/LOG directory. This default
5070 location can be changed by setting the MAKEALL_LOGDIR environment
5071 variable. For example:
5072
5073 export BUILD_DIR=/tmp/build
5074 export MAKEALL_LOGDIR=/tmp/log
5075 CROSS_COMPILE=ppc_8xx- MAKEALL
5076
5077 With the above settings build objects are saved in the /tmp/build,
5078 log files are saved in the /tmp/log and the source tree remains clean
5079 during the whole build process.
5080
5081
5082 See also "U-Boot Porting Guide" below.
5083
5084
5085 Monitor Commands - Overview:
5086 ============================
5087
5088 go - start application at address 'addr'
5089 run - run commands in an environment variable
5090 bootm - boot application image from memory
5091 bootp - boot image via network using BootP/TFTP protocol
5092 bootz - boot zImage from memory
5093 tftpboot- boot image via network using TFTP protocol
5094 and env variables "ipaddr" and "serverip"
5095 (and eventually "gatewayip")
5096 tftpput - upload a file via network using TFTP protocol
5097 rarpboot- boot image via network using RARP/TFTP protocol
5098 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
5099 loads - load S-Record file over serial line
5100 loadb - load binary file over serial line (kermit mode)
5101 md - memory display
5102 mm - memory modify (auto-incrementing)
5103 nm - memory modify (constant address)
5104 mw - memory write (fill)
5105 cp - memory copy
5106 cmp - memory compare
5107 crc32 - checksum calculation
5108 i2c - I2C sub-system
5109 sspi - SPI utility commands
5110 base - print or set address offset
5111 printenv- print environment variables
5112 setenv - set environment variables
5113 saveenv - save environment variables to persistent storage
5114 protect - enable or disable FLASH write protection
5115 erase - erase FLASH memory
5116 flinfo - print FLASH memory information
5117 nand - NAND memory operations (see doc/README.nand)
5118 bdinfo - print Board Info structure
5119 iminfo - print header information for application image
5120 coninfo - print console devices and informations
5121 ide - IDE sub-system
5122 loop - infinite loop on address range
5123 loopw - infinite write loop on address range
5124 mtest - simple RAM test
5125 icache - enable or disable instruction cache
5126 dcache - enable or disable data cache
5127 reset - Perform RESET of the CPU
5128 echo - echo args to console
5129 version - print monitor version
5130 help - print online help
5131 ? - alias for 'help'
5132
5133
5134 Monitor Commands - Detailed Description:
5135 ========================================
5136
5137 TODO.
5138
5139 For now: just type "help <command>".
5140
5141
5142 Environment Variables:
5143 ======================
5144
5145 U-Boot supports user configuration using Environment Variables which
5146 can be made persistent by saving to Flash memory.
5147
5148 Environment Variables are set using "setenv", printed using
5149 "printenv", and saved to Flash using "saveenv". Using "setenv"
5150 without a value can be used to delete a variable from the
5151 environment. As long as you don't save the environment you are
5152 working with an in-memory copy. In case the Flash area containing the
5153 environment is erased by accident, a default environment is provided.
5154
5155 Some configuration options can be set using Environment Variables.
5156
5157 List of environment variables (most likely not complete):
5158
5159 baudrate - see CONFIG_BAUDRATE
5160
5161 bootdelay - see CONFIG_BOOTDELAY
5162
5163 bootcmd - see CONFIG_BOOTCOMMAND
5164
5165 bootargs - Boot arguments when booting an RTOS image
5166
5167 bootfile - Name of the image to load with TFTP
5168
5169 bootm_low - Memory range available for image processing in the bootm
5170 command can be restricted. This variable is given as
5171 a hexadecimal number and defines lowest address allowed
5172 for use by the bootm command. See also "bootm_size"
5173 environment variable. Address defined by "bootm_low" is
5174 also the base of the initial memory mapping for the Linux
5175 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
5176 bootm_mapsize.
5177
5178 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
5179 This variable is given as a hexadecimal number and it
5180 defines the size of the memory region starting at base
5181 address bootm_low that is accessible by the Linux kernel
5182 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
5183 as the default value if it is defined, and bootm_size is
5184 used otherwise.
5185
5186 bootm_size - Memory range available for image processing in the bootm
5187 command can be restricted. This variable is given as
5188 a hexadecimal number and defines the size of the region
5189 allowed for use by the bootm command. See also "bootm_low"
5190 environment variable.
5191
5192 updatefile - Location of the software update file on a TFTP server, used
5193 by the automatic software update feature. Please refer to
5194 documentation in doc/README.update for more details.
5195
5196 autoload - if set to "no" (any string beginning with 'n'),
5197 "bootp" will just load perform a lookup of the
5198 configuration from the BOOTP server, but not try to
5199 load any image using TFTP
5200
5201 autostart - if set to "yes", an image loaded using the "bootp",
5202 "rarpboot", "tftpboot" or "diskboot" commands will
5203 be automatically started (by internally calling
5204 "bootm")
5205
5206 If set to "no", a standalone image passed to the
5207 "bootm" command will be copied to the load address
5208 (and eventually uncompressed), but NOT be started.
5209 This can be used to load and uncompress arbitrary
5210 data.
5211
5212 fdt_high - if set this restricts the maximum address that the
5213 flattened device tree will be copied into upon boot.
5214 For example, if you have a system with 1 GB memory
5215 at physical address 0x10000000, while Linux kernel
5216 only recognizes the first 704 MB as low memory, you
5217 may need to set fdt_high as 0x3C000000 to have the
5218 device tree blob be copied to the maximum address
5219 of the 704 MB low memory, so that Linux kernel can
5220 access it during the boot procedure.
5221
5222 If this is set to the special value 0xFFFFFFFF then
5223 the fdt will not be copied at all on boot. For this
5224 to work it must reside in writable memory, have
5225 sufficient padding on the end of it for u-boot to
5226 add the information it needs into it, and the memory
5227 must be accessible by the kernel.
5228
5229 fdtcontroladdr- if set this is the address of the control flattened
5230 device tree used by U-Boot when CONFIG_OF_CONTROL is
5231 defined.
5232
5233 i2cfast - (PPC405GP|PPC405EP only)
5234 if set to 'y' configures Linux I2C driver for fast
5235 mode (400kHZ). This environment variable is used in
5236 initialization code. So, for changes to be effective
5237 it must be saved and board must be reset.
5238
5239 initrd_high - restrict positioning of initrd images:
5240 If this variable is not set, initrd images will be
5241 copied to the highest possible address in RAM; this
5242 is usually what you want since it allows for
5243 maximum initrd size. If for some reason you want to
5244 make sure that the initrd image is loaded below the
5245 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
5246 variable to a value of "no" or "off" or "0".
5247 Alternatively, you can set it to a maximum upper
5248 address to use (U-Boot will still check that it
5249 does not overwrite the U-Boot stack and data).
5250
5251 For instance, when you have a system with 16 MB
5252 RAM, and want to reserve 4 MB from use by Linux,
5253 you can do this by adding "mem=12M" to the value of
5254 the "bootargs" variable. However, now you must make
5255 sure that the initrd image is placed in the first
5256 12 MB as well - this can be done with
5257
5258 setenv initrd_high 00c00000
5259
5260 If you set initrd_high to 0xFFFFFFFF, this is an
5261 indication to U-Boot that all addresses are legal
5262 for the Linux kernel, including addresses in flash
5263 memory. In this case U-Boot will NOT COPY the
5264 ramdisk at all. This may be useful to reduce the
5265 boot time on your system, but requires that this
5266 feature is supported by your Linux kernel.
5267
5268 ipaddr - IP address; needed for tftpboot command
5269
5270 loadaddr - Default load address for commands like "bootp",
5271 "rarpboot", "tftpboot", "loadb" or "diskboot"
5272
5273 loads_echo - see CONFIG_LOADS_ECHO
5274
5275 serverip - TFTP server IP address; needed for tftpboot command
5276
5277 bootretry - see CONFIG_BOOT_RETRY_TIME
5278
5279 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
5280
5281 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
5282
5283 ethprime - controls which interface is used first.
5284
5285 ethact - controls which interface is currently active.
5286 For example you can do the following
5287
5288 => setenv ethact FEC
5289 => ping 192.168.0.1 # traffic sent on FEC
5290 => setenv ethact SCC
5291 => ping 10.0.0.1 # traffic sent on SCC
5292
5293 ethrotate - When set to "no" U-Boot does not go through all
5294 available network interfaces.
5295 It just stays at the currently selected interface.
5296
5297 netretry - When set to "no" each network operation will
5298 either succeed or fail without retrying.
5299 When set to "once" the network operation will
5300 fail when all the available network interfaces
5301 are tried once without success.
5302 Useful on scripts which control the retry operation
5303 themselves.
5304
5305 npe_ucode - set load address for the NPE microcode
5306
5307 silent_linux - If set then linux will be told to boot silently, by
5308 changing the console to be empty. If "yes" it will be
5309 made silent. If "no" it will not be made silent. If
5310 unset, then it will be made silent if the U-Boot console
5311 is silent.
5312
5313 tftpsrcport - If this is set, the value is used for TFTP's
5314 UDP source port.
5315
5316 tftpdstport - If this is set, the value is used for TFTP's UDP
5317 destination port instead of the Well Know Port 69.
5318
5319 tftpblocksize - Block size to use for TFTP transfers; if not set,
5320 we use the TFTP server's default block size
5321
5322 tftptimeout - Retransmission timeout for TFTP packets (in milli-
5323 seconds, minimum value is 1000 = 1 second). Defines
5324 when a packet is considered to be lost so it has to
5325 be retransmitted. The default is 5000 = 5 seconds.
5326 Lowering this value may make downloads succeed
5327 faster in networks with high packet loss rates or
5328 with unreliable TFTP servers.
5329
5330 vlan - When set to a value < 4095 the traffic over
5331 Ethernet is encapsulated/received over 802.1q
5332 VLAN tagged frames.
5333
5334 The following image location variables contain the location of images
5335 used in booting. The "Image" column gives the role of the image and is
5336 not an environment variable name. The other columns are environment
5337 variable names. "File Name" gives the name of the file on a TFTP
5338 server, "RAM Address" gives the location in RAM the image will be
5339 loaded to, and "Flash Location" gives the image's address in NOR
5340 flash or offset in NAND flash.
5341
5342 *Note* - these variables don't have to be defined for all boards, some
5343 boards currenlty use other variables for these purposes, and some
5344 boards use these variables for other purposes.
5345
5346 Image File Name RAM Address Flash Location
5347 ----- --------- ----------- --------------
5348 u-boot u-boot u-boot_addr_r u-boot_addr
5349 Linux kernel bootfile kernel_addr_r kernel_addr
5350 device tree blob fdtfile fdt_addr_r fdt_addr
5351 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
5352
5353 The following environment variables may be used and automatically
5354 updated by the network boot commands ("bootp" and "rarpboot"),
5355 depending the information provided by your boot server:
5356
5357 bootfile - see above
5358 dnsip - IP address of your Domain Name Server
5359 dnsip2 - IP address of your secondary Domain Name Server
5360 gatewayip - IP address of the Gateway (Router) to use
5361 hostname - Target hostname
5362 ipaddr - see above
5363 netmask - Subnet Mask
5364 rootpath - Pathname of the root filesystem on the NFS server
5365 serverip - see above
5366
5367
5368 There are two special Environment Variables:
5369
5370 serial# - contains hardware identification information such
5371 as type string and/or serial number
5372 ethaddr - Ethernet address
5373
5374 These variables can be set only once (usually during manufacturing of
5375 the board). U-Boot refuses to delete or overwrite these variables
5376 once they have been set once.
5377
5378
5379 Further special Environment Variables:
5380
5381 ver - Contains the U-Boot version string as printed
5382 with the "version" command. This variable is
5383 readonly (see CONFIG_VERSION_VARIABLE).
5384
5385
5386 Please note that changes to some configuration parameters may take
5387 only effect after the next boot (yes, that's just like Windoze :-).
5388
5389
5390 Callback functions for environment variables:
5391 ---------------------------------------------
5392
5393 For some environment variables, the behavior of u-boot needs to change
5394 when their values are changed. This functionailty allows functions to
5395 be associated with arbitrary variables. On creation, overwrite, or
5396 deletion, the callback will provide the opportunity for some side
5397 effect to happen or for the change to be rejected.
5398
5399 The callbacks are named and associated with a function using the
5400 U_BOOT_ENV_CALLBACK macro in your board or driver code.
5401
5402 These callbacks are associated with variables in one of two ways. The
5403 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
5404 in the board configuration to a string that defines a list of
5405 associations. The list must be in the following format:
5406
5407 entry = variable_name[:callback_name]
5408 list = entry[,list]
5409
5410 If the callback name is not specified, then the callback is deleted.
5411 Spaces are also allowed anywhere in the list.
5412
5413 Callbacks can also be associated by defining the ".callbacks" variable
5414 with the same list format above. Any association in ".callbacks" will
5415 override any association in the static list. You can define
5416 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
5417 ".callbacks" envirnoment variable in the default or embedded environment.
5418
5419
5420 Command Line Parsing:
5421 =====================
5422
5423 There are two different command line parsers available with U-Boot:
5424 the old "simple" one, and the much more powerful "hush" shell:
5425
5426 Old, simple command line parser:
5427 --------------------------------
5428
5429 - supports environment variables (through setenv / saveenv commands)
5430 - several commands on one line, separated by ';'
5431 - variable substitution using "... ${name} ..." syntax
5432 - special characters ('$', ';') can be escaped by prefixing with '\',
5433 for example:
5434 setenv bootcmd bootm \${address}
5435 - You can also escape text by enclosing in single apostrophes, for example:
5436 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
5437
5438 Hush shell:
5439 -----------
5440
5441 - similar to Bourne shell, with control structures like
5442 if...then...else...fi, for...do...done; while...do...done,
5443 until...do...done, ...
5444 - supports environment ("global") variables (through setenv / saveenv
5445 commands) and local shell variables (through standard shell syntax
5446 "name=value"); only environment variables can be used with "run"
5447 command
5448
5449 General rules:
5450 --------------
5451
5452 (1) If a command line (or an environment variable executed by a "run"
5453 command) contains several commands separated by semicolon, and
5454 one of these commands fails, then the remaining commands will be
5455 executed anyway.
5456
5457 (2) If you execute several variables with one call to run (i. e.
5458 calling run with a list of variables as arguments), any failing
5459 command will cause "run" to terminate, i. e. the remaining
5460 variables are not executed.
5461
5462 Note for Redundant Ethernet Interfaces:
5463 =======================================
5464
5465 Some boards come with redundant Ethernet interfaces; U-Boot supports
5466 such configurations and is capable of automatic selection of a
5467 "working" interface when needed. MAC assignment works as follows:
5468
5469 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
5470 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
5471 "eth1addr" (=>eth1), "eth2addr", ...
5472
5473 If the network interface stores some valid MAC address (for instance
5474 in SROM), this is used as default address if there is NO correspon-
5475 ding setting in the environment; if the corresponding environment
5476 variable is set, this overrides the settings in the card; that means:
5477
5478 o If the SROM has a valid MAC address, and there is no address in the
5479 environment, the SROM's address is used.
5480
5481 o If there is no valid address in the SROM, and a definition in the
5482 environment exists, then the value from the environment variable is
5483 used.
5484
5485 o If both the SROM and the environment contain a MAC address, and
5486 both addresses are the same, this MAC address is used.
5487
5488 o If both the SROM and the environment contain a MAC address, and the
5489 addresses differ, the value from the environment is used and a
5490 warning is printed.
5491
5492 o If neither SROM nor the environment contain a MAC address, an error
5493 is raised.
5494
5495 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
5496 will be programmed into hardware as part of the initialization process. This
5497 may be skipped by setting the appropriate 'ethmacskip' environment variable.
5498 The naming convention is as follows:
5499 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
5500
5501 Image Formats:
5502 ==============
5503
5504 U-Boot is capable of booting (and performing other auxiliary operations on)
5505 images in two formats:
5506
5507 New uImage format (FIT)
5508 -----------------------
5509
5510 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
5511 to Flattened Device Tree). It allows the use of images with multiple
5512 components (several kernels, ramdisks, etc.), with contents protected by
5513 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
5514
5515
5516 Old uImage format
5517 -----------------
5518
5519 Old image format is based on binary files which can be basically anything,
5520 preceded by a special header; see the definitions in include/image.h for
5521 details; basically, the header defines the following image properties:
5522
5523 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
5524 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
5525 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
5526 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
5527 INTEGRITY).
5528 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
5529 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
5530 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
5531 * Compression Type (uncompressed, gzip, bzip2)
5532 * Load Address
5533 * Entry Point
5534 * Image Name
5535 * Image Timestamp
5536
5537 The header is marked by a special Magic Number, and both the header
5538 and the data portions of the image are secured against corruption by
5539 CRC32 checksums.
5540
5541
5542 Linux Support:
5543 ==============
5544
5545 Although U-Boot should support any OS or standalone application
5546 easily, the main focus has always been on Linux during the design of
5547 U-Boot.
5548
5549 U-Boot includes many features that so far have been part of some
5550 special "boot loader" code within the Linux kernel. Also, any
5551 "initrd" images to be used are no longer part of one big Linux image;
5552 instead, kernel and "initrd" are separate images. This implementation
5553 serves several purposes:
5554
5555 - the same features can be used for other OS or standalone
5556 applications (for instance: using compressed images to reduce the
5557 Flash memory footprint)
5558
5559 - it becomes much easier to port new Linux kernel versions because
5560 lots of low-level, hardware dependent stuff are done by U-Boot
5561
5562 - the same Linux kernel image can now be used with different "initrd"
5563 images; of course this also means that different kernel images can
5564 be run with the same "initrd". This makes testing easier (you don't
5565 have to build a new "zImage.initrd" Linux image when you just
5566 change a file in your "initrd"). Also, a field-upgrade of the
5567 software is easier now.
5568
5569
5570 Linux HOWTO:
5571 ============
5572
5573 Porting Linux to U-Boot based systems:
5574 ---------------------------------------
5575
5576 U-Boot cannot save you from doing all the necessary modifications to
5577 configure the Linux device drivers for use with your target hardware
5578 (no, we don't intend to provide a full virtual machine interface to
5579 Linux :-).
5580
5581 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
5582
5583 Just make sure your machine specific header file (for instance
5584 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
5585 Information structure as we define in include/asm-<arch>/u-boot.h,
5586 and make sure that your definition of IMAP_ADDR uses the same value
5587 as your U-Boot configuration in CONFIG_SYS_IMMR.
5588
5589 Note that U-Boot now has a driver model, a unified model for drivers.
5590 If you are adding a new driver, plumb it into driver model. If there
5591 is no uclass available, you are encouraged to create one. See
5592 doc/driver-model.
5593
5594
5595 Configuring the Linux kernel:
5596 -----------------------------
5597
5598 No specific requirements for U-Boot. Make sure you have some root
5599 device (initial ramdisk, NFS) for your target system.
5600
5601
5602 Building a Linux Image:
5603 -----------------------
5604
5605 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5606 not used. If you use recent kernel source, a new build target
5607 "uImage" will exist which automatically builds an image usable by
5608 U-Boot. Most older kernels also have support for a "pImage" target,
5609 which was introduced for our predecessor project PPCBoot and uses a
5610 100% compatible format.
5611
5612 Example:
5613
5614 make TQM850L_defconfig
5615 make oldconfig
5616 make dep
5617 make uImage
5618
5619 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5620 encapsulate a compressed Linux kernel image with header information,
5621 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5622
5623 * build a standard "vmlinux" kernel image (in ELF binary format):
5624
5625 * convert the kernel into a raw binary image:
5626
5627 ${CROSS_COMPILE}-objcopy -O binary \
5628 -R .note -R .comment \
5629 -S vmlinux linux.bin
5630
5631 * compress the binary image:
5632
5633 gzip -9 linux.bin
5634
5635 * package compressed binary image for U-Boot:
5636
5637 mkimage -A ppc -O linux -T kernel -C gzip \
5638 -a 0 -e 0 -n "Linux Kernel Image" \
5639 -d linux.bin.gz uImage
5640
5641
5642 The "mkimage" tool can also be used to create ramdisk images for use
5643 with U-Boot, either separated from the Linux kernel image, or
5644 combined into one file. "mkimage" encapsulates the images with a 64
5645 byte header containing information about target architecture,
5646 operating system, image type, compression method, entry points, time
5647 stamp, CRC32 checksums, etc.
5648
5649 "mkimage" can be called in two ways: to verify existing images and
5650 print the header information, or to build new images.
5651
5652 In the first form (with "-l" option) mkimage lists the information
5653 contained in the header of an existing U-Boot image; this includes
5654 checksum verification:
5655
5656 tools/mkimage -l image
5657 -l ==> list image header information
5658
5659 The second form (with "-d" option) is used to build a U-Boot image
5660 from a "data file" which is used as image payload:
5661
5662 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5663 -n name -d data_file image
5664 -A ==> set architecture to 'arch'
5665 -O ==> set operating system to 'os'
5666 -T ==> set image type to 'type'
5667 -C ==> set compression type 'comp'
5668 -a ==> set load address to 'addr' (hex)
5669 -e ==> set entry point to 'ep' (hex)
5670 -n ==> set image name to 'name'
5671 -d ==> use image data from 'datafile'
5672
5673 Right now, all Linux kernels for PowerPC systems use the same load
5674 address (0x00000000), but the entry point address depends on the
5675 kernel version:
5676
5677 - 2.2.x kernels have the entry point at 0x0000000C,
5678 - 2.3.x and later kernels have the entry point at 0x00000000.
5679
5680 So a typical call to build a U-Boot image would read:
5681
5682 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5683 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5684 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5685 > examples/uImage.TQM850L
5686 Image Name: 2.4.4 kernel for TQM850L
5687 Created: Wed Jul 19 02:34:59 2000
5688 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5689 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5690 Load Address: 0x00000000
5691 Entry Point: 0x00000000
5692
5693 To verify the contents of the image (or check for corruption):
5694
5695 -> tools/mkimage -l examples/uImage.TQM850L
5696 Image Name: 2.4.4 kernel for TQM850L
5697 Created: Wed Jul 19 02:34:59 2000
5698 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5699 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5700 Load Address: 0x00000000
5701 Entry Point: 0x00000000
5702
5703 NOTE: for embedded systems where boot time is critical you can trade
5704 speed for memory and install an UNCOMPRESSED image instead: this
5705 needs more space in Flash, but boots much faster since it does not
5706 need to be uncompressed:
5707
5708 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5709 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5710 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5711 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5712 > examples/uImage.TQM850L-uncompressed
5713 Image Name: 2.4.4 kernel for TQM850L
5714 Created: Wed Jul 19 02:34:59 2000
5715 Image Type: PowerPC Linux Kernel Image (uncompressed)
5716 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5717 Load Address: 0x00000000
5718 Entry Point: 0x00000000
5719
5720
5721 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5722 when your kernel is intended to use an initial ramdisk:
5723
5724 -> tools/mkimage -n 'Simple Ramdisk Image' \
5725 > -A ppc -O linux -T ramdisk -C gzip \
5726 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5727 Image Name: Simple Ramdisk Image
5728 Created: Wed Jan 12 14:01:50 2000
5729 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5730 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5731 Load Address: 0x00000000
5732 Entry Point: 0x00000000
5733
5734 The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
5735 option performs the converse operation of the mkimage's second form (the "-d"
5736 option). Given an image built by mkimage, the dumpimage extracts a "data file"
5737 from the image:
5738
5739 tools/dumpimage -i image -p position data_file
5740 -i ==> extract from the 'image' a specific 'data_file', \
5741 indexed by 'position'
5742
5743
5744 Installing a Linux Image:
5745 -------------------------
5746
5747 To downloading a U-Boot image over the serial (console) interface,
5748 you must convert the image to S-Record format:
5749
5750 objcopy -I binary -O srec examples/image examples/image.srec
5751
5752 The 'objcopy' does not understand the information in the U-Boot
5753 image header, so the resulting S-Record file will be relative to
5754 address 0x00000000. To load it to a given address, you need to
5755 specify the target address as 'offset' parameter with the 'loads'
5756 command.
5757
5758 Example: install the image to address 0x40100000 (which on the
5759 TQM8xxL is in the first Flash bank):
5760
5761 => erase 40100000 401FFFFF
5762
5763 .......... done
5764 Erased 8 sectors
5765
5766 => loads 40100000
5767 ## Ready for S-Record download ...
5768 ~>examples/image.srec
5769 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5770 ...
5771 15989 15990 15991 15992
5772 [file transfer complete]
5773 [connected]
5774 ## Start Addr = 0x00000000
5775
5776
5777 You can check the success of the download using the 'iminfo' command;
5778 this includes a checksum verification so you can be sure no data
5779 corruption happened:
5780
5781 => imi 40100000
5782
5783 ## Checking Image at 40100000 ...
5784 Image Name: 2.2.13 for initrd on TQM850L
5785 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5786 Data Size: 335725 Bytes = 327 kB = 0 MB
5787 Load Address: 00000000
5788 Entry Point: 0000000c
5789 Verifying Checksum ... OK
5790
5791
5792 Boot Linux:
5793 -----------
5794
5795 The "bootm" command is used to boot an application that is stored in
5796 memory (RAM or Flash). In case of a Linux kernel image, the contents
5797 of the "bootargs" environment variable is passed to the kernel as
5798 parameters. You can check and modify this variable using the
5799 "printenv" and "setenv" commands:
5800
5801
5802 => printenv bootargs
5803 bootargs=root=/dev/ram
5804
5805 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5806
5807 => printenv bootargs
5808 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5809
5810 => bootm 40020000
5811 ## Booting Linux kernel at 40020000 ...
5812 Image Name: 2.2.13 for NFS on TQM850L
5813 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5814 Data Size: 381681 Bytes = 372 kB = 0 MB
5815 Load Address: 00000000
5816 Entry Point: 0000000c
5817 Verifying Checksum ... OK
5818 Uncompressing Kernel Image ... OK
5819 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
5820 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5821 time_init: decrementer frequency = 187500000/60
5822 Calibrating delay loop... 49.77 BogoMIPS
5823 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5824 ...
5825
5826 If you want to boot a Linux kernel with initial RAM disk, you pass
5827 the memory addresses of both the kernel and the initrd image (PPBCOOT
5828 format!) to the "bootm" command:
5829
5830 => imi 40100000 40200000
5831
5832 ## Checking Image at 40100000 ...
5833 Image Name: 2.2.13 for initrd on TQM850L
5834 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5835 Data Size: 335725 Bytes = 327 kB = 0 MB
5836 Load Address: 00000000
5837 Entry Point: 0000000c
5838 Verifying Checksum ... OK
5839
5840 ## Checking Image at 40200000 ...
5841 Image Name: Simple Ramdisk Image
5842 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5843 Data Size: 566530 Bytes = 553 kB = 0 MB
5844 Load Address: 00000000
5845 Entry Point: 00000000
5846 Verifying Checksum ... OK
5847
5848 => bootm 40100000 40200000
5849 ## Booting Linux kernel at 40100000 ...
5850 Image Name: 2.2.13 for initrd on TQM850L
5851 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5852 Data Size: 335725 Bytes = 327 kB = 0 MB
5853 Load Address: 00000000
5854 Entry Point: 0000000c
5855 Verifying Checksum ... OK
5856 Uncompressing Kernel Image ... OK
5857 ## Loading RAMDisk Image at 40200000 ...
5858 Image Name: Simple Ramdisk Image
5859 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5860 Data Size: 566530 Bytes = 553 kB = 0 MB
5861 Load Address: 00000000
5862 Entry Point: 00000000
5863 Verifying Checksum ... OK
5864 Loading Ramdisk ... OK
5865 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
5866 Boot arguments: root=/dev/ram
5867 time_init: decrementer frequency = 187500000/60
5868 Calibrating delay loop... 49.77 BogoMIPS
5869 ...
5870 RAMDISK: Compressed image found at block 0
5871 VFS: Mounted root (ext2 filesystem).
5872
5873 bash#
5874
5875 Boot Linux and pass a flat device tree:
5876 -----------
5877
5878 First, U-Boot must be compiled with the appropriate defines. See the section
5879 titled "Linux Kernel Interface" above for a more in depth explanation. The
5880 following is an example of how to start a kernel and pass an updated
5881 flat device tree:
5882
5883 => print oftaddr
5884 oftaddr=0x300000
5885 => print oft
5886 oft=oftrees/mpc8540ads.dtb
5887 => tftp $oftaddr $oft
5888 Speed: 1000, full duplex
5889 Using TSEC0 device
5890 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5891 Filename 'oftrees/mpc8540ads.dtb'.
5892 Load address: 0x300000
5893 Loading: #
5894 done
5895 Bytes transferred = 4106 (100a hex)
5896 => tftp $loadaddr $bootfile
5897 Speed: 1000, full duplex
5898 Using TSEC0 device
5899 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5900 Filename 'uImage'.
5901 Load address: 0x200000
5902 Loading:############
5903 done
5904 Bytes transferred = 1029407 (fb51f hex)
5905 => print loadaddr
5906 loadaddr=200000
5907 => print oftaddr
5908 oftaddr=0x300000
5909 => bootm $loadaddr - $oftaddr
5910 ## Booting image at 00200000 ...
5911 Image Name: Linux-2.6.17-dirty
5912 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5913 Data Size: 1029343 Bytes = 1005.2 kB
5914 Load Address: 00000000
5915 Entry Point: 00000000
5916 Verifying Checksum ... OK
5917 Uncompressing Kernel Image ... OK
5918 Booting using flat device tree at 0x300000
5919 Using MPC85xx ADS machine description
5920 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5921 [snip]
5922
5923
5924 More About U-Boot Image Types:
5925 ------------------------------
5926
5927 U-Boot supports the following image types:
5928
5929 "Standalone Programs" are directly runnable in the environment
5930 provided by U-Boot; it is expected that (if they behave
5931 well) you can continue to work in U-Boot after return from
5932 the Standalone Program.
5933 "OS Kernel Images" are usually images of some Embedded OS which
5934 will take over control completely. Usually these programs
5935 will install their own set of exception handlers, device
5936 drivers, set up the MMU, etc. - this means, that you cannot
5937 expect to re-enter U-Boot except by resetting the CPU.
5938 "RAMDisk Images" are more or less just data blocks, and their
5939 parameters (address, size) are passed to an OS kernel that is
5940 being started.
5941 "Multi-File Images" contain several images, typically an OS
5942 (Linux) kernel image and one or more data images like
5943 RAMDisks. This construct is useful for instance when you want
5944 to boot over the network using BOOTP etc., where the boot
5945 server provides just a single image file, but you want to get
5946 for instance an OS kernel and a RAMDisk image.
5947
5948 "Multi-File Images" start with a list of image sizes, each
5949 image size (in bytes) specified by an "uint32_t" in network
5950 byte order. This list is terminated by an "(uint32_t)0".
5951 Immediately after the terminating 0 follow the images, one by
5952 one, all aligned on "uint32_t" boundaries (size rounded up to
5953 a multiple of 4 bytes).
5954
5955 "Firmware Images" are binary images containing firmware (like
5956 U-Boot or FPGA images) which usually will be programmed to
5957 flash memory.
5958
5959 "Script files" are command sequences that will be executed by
5960 U-Boot's command interpreter; this feature is especially
5961 useful when you configure U-Boot to use a real shell (hush)
5962 as command interpreter.
5963
5964 Booting the Linux zImage:
5965 -------------------------
5966
5967 On some platforms, it's possible to boot Linux zImage. This is done
5968 using the "bootz" command. The syntax of "bootz" command is the same
5969 as the syntax of "bootm" command.
5970
5971 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5972 kernel with raw initrd images. The syntax is slightly different, the
5973 address of the initrd must be augmented by it's size, in the following
5974 format: "<initrd addres>:<initrd size>".
5975
5976
5977 Standalone HOWTO:
5978 =================
5979
5980 One of the features of U-Boot is that you can dynamically load and
5981 run "standalone" applications, which can use some resources of
5982 U-Boot like console I/O functions or interrupt services.
5983
5984 Two simple examples are included with the sources:
5985
5986 "Hello World" Demo:
5987 -------------------
5988
5989 'examples/hello_world.c' contains a small "Hello World" Demo
5990 application; it is automatically compiled when you build U-Boot.
5991 It's configured to run at address 0x00040004, so you can play with it
5992 like that:
5993
5994 => loads
5995 ## Ready for S-Record download ...
5996 ~>examples/hello_world.srec
5997 1 2 3 4 5 6 7 8 9 10 11 ...
5998 [file transfer complete]
5999 [connected]
6000 ## Start Addr = 0x00040004
6001
6002 => go 40004 Hello World! This is a test.
6003 ## Starting application at 0x00040004 ...
6004 Hello World
6005 argc = 7
6006 argv[0] = "40004"
6007 argv[1] = "Hello"
6008 argv[2] = "World!"
6009 argv[3] = "This"
6010 argv[4] = "is"
6011 argv[5] = "a"
6012 argv[6] = "test."
6013 argv[7] = "<NULL>"
6014 Hit any key to exit ...
6015
6016 ## Application terminated, rc = 0x0
6017
6018 Another example, which demonstrates how to register a CPM interrupt
6019 handler with the U-Boot code, can be found in 'examples/timer.c'.
6020 Here, a CPM timer is set up to generate an interrupt every second.
6021 The interrupt service routine is trivial, just printing a '.'
6022 character, but this is just a demo program. The application can be
6023 controlled by the following keys:
6024
6025 ? - print current values og the CPM Timer registers
6026 b - enable interrupts and start timer
6027 e - stop timer and disable interrupts
6028 q - quit application
6029
6030 => loads
6031 ## Ready for S-Record download ...
6032 ~>examples/timer.srec
6033 1 2 3 4 5 6 7 8 9 10 11 ...
6034 [file transfer complete]
6035 [connected]
6036 ## Start Addr = 0x00040004
6037
6038 => go 40004
6039 ## Starting application at 0x00040004 ...
6040 TIMERS=0xfff00980
6041 Using timer 1
6042 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
6043
6044 Hit 'b':
6045 [q, b, e, ?] Set interval 1000000 us
6046 Enabling timer
6047 Hit '?':
6048 [q, b, e, ?] ........
6049 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
6050 Hit '?':
6051 [q, b, e, ?] .
6052 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
6053 Hit '?':
6054 [q, b, e, ?] .
6055 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
6056 Hit '?':
6057 [q, b, e, ?] .
6058 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
6059 Hit 'e':
6060 [q, b, e, ?] ...Stopping timer
6061 Hit 'q':
6062 [q, b, e, ?] ## Application terminated, rc = 0x0
6063
6064
6065 Minicom warning:
6066 ================
6067
6068 Over time, many people have reported problems when trying to use the
6069 "minicom" terminal emulation program for serial download. I (wd)
6070 consider minicom to be broken, and recommend not to use it. Under
6071 Unix, I recommend to use C-Kermit for general purpose use (and
6072 especially for kermit binary protocol download ("loadb" command), and
6073 use "cu" for S-Record download ("loads" command). See
6074 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
6075 for help with kermit.
6076
6077
6078 Nevertheless, if you absolutely want to use it try adding this
6079 configuration to your "File transfer protocols" section:
6080
6081 Name Program Name U/D FullScr IO-Red. Multi
6082 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
6083 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
6084
6085
6086 NetBSD Notes:
6087 =============
6088
6089 Starting at version 0.9.2, U-Boot supports NetBSD both as host
6090 (build U-Boot) and target system (boots NetBSD/mpc8xx).
6091
6092 Building requires a cross environment; it is known to work on
6093 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
6094 need gmake since the Makefiles are not compatible with BSD make).
6095 Note that the cross-powerpc package does not install include files;
6096 attempting to build U-Boot will fail because <machine/ansi.h> is
6097 missing. This file has to be installed and patched manually:
6098
6099 # cd /usr/pkg/cross/powerpc-netbsd/include
6100 # mkdir powerpc
6101 # ln -s powerpc machine
6102 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
6103 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
6104
6105 Native builds *don't* work due to incompatibilities between native
6106 and U-Boot include files.
6107
6108 Booting assumes that (the first part of) the image booted is a
6109 stage-2 loader which in turn loads and then invokes the kernel
6110 proper. Loader sources will eventually appear in the NetBSD source
6111 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
6112 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
6113
6114
6115 Implementation Internals:
6116 =========================
6117
6118 The following is not intended to be a complete description of every
6119 implementation detail. However, it should help to understand the
6120 inner workings of U-Boot and make it easier to port it to custom
6121 hardware.
6122
6123
6124 Initial Stack, Global Data:
6125 ---------------------------
6126
6127 The implementation of U-Boot is complicated by the fact that U-Boot
6128 starts running out of ROM (flash memory), usually without access to
6129 system RAM (because the memory controller is not initialized yet).
6130 This means that we don't have writable Data or BSS segments, and BSS
6131 is not initialized as zero. To be able to get a C environment working
6132 at all, we have to allocate at least a minimal stack. Implementation
6133 options for this are defined and restricted by the CPU used: Some CPU
6134 models provide on-chip memory (like the IMMR area on MPC8xx and
6135 MPC826x processors), on others (parts of) the data cache can be
6136 locked as (mis-) used as memory, etc.
6137
6138 Chris Hallinan posted a good summary of these issues to the
6139 U-Boot mailing list:
6140
6141 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
6142 From: "Chris Hallinan" <clh@net1plus.com>
6143 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
6144 ...
6145
6146 Correct me if I'm wrong, folks, but the way I understand it
6147 is this: Using DCACHE as initial RAM for Stack, etc, does not
6148 require any physical RAM backing up the cache. The cleverness
6149 is that the cache is being used as a temporary supply of
6150 necessary storage before the SDRAM controller is setup. It's
6151 beyond the scope of this list to explain the details, but you
6152 can see how this works by studying the cache architecture and
6153 operation in the architecture and processor-specific manuals.
6154
6155 OCM is On Chip Memory, which I believe the 405GP has 4K. It
6156 is another option for the system designer to use as an
6157 initial stack/RAM area prior to SDRAM being available. Either
6158 option should work for you. Using CS 4 should be fine if your
6159 board designers haven't used it for something that would
6160 cause you grief during the initial boot! It is frequently not
6161 used.
6162
6163 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
6164 with your processor/board/system design. The default value
6165 you will find in any recent u-boot distribution in
6166 walnut.h should work for you. I'd set it to a value larger
6167 than your SDRAM module. If you have a 64MB SDRAM module, set
6168 it above 400_0000. Just make sure your board has no resources
6169 that are supposed to respond to that address! That code in
6170 start.S has been around a while and should work as is when
6171 you get the config right.
6172
6173 -Chris Hallinan
6174 DS4.COM, Inc.
6175
6176 It is essential to remember this, since it has some impact on the C
6177 code for the initialization procedures:
6178
6179 * Initialized global data (data segment) is read-only. Do not attempt
6180 to write it.
6181
6182 * Do not use any uninitialized global data (or implicitely initialized
6183 as zero data - BSS segment) at all - this is undefined, initiali-
6184 zation is performed later (when relocating to RAM).
6185
6186 * Stack space is very limited. Avoid big data buffers or things like
6187 that.
6188
6189 Having only the stack as writable memory limits means we cannot use
6190 normal global data to share information beween the code. But it
6191 turned out that the implementation of U-Boot can be greatly
6192 simplified by making a global data structure (gd_t) available to all
6193 functions. We could pass a pointer to this data as argument to _all_
6194 functions, but this would bloat the code. Instead we use a feature of
6195 the GCC compiler (Global Register Variables) to share the data: we
6196 place a pointer (gd) to the global data into a register which we
6197 reserve for this purpose.
6198
6199 When choosing a register for such a purpose we are restricted by the
6200 relevant (E)ABI specifications for the current architecture, and by
6201 GCC's implementation.
6202
6203 For PowerPC, the following registers have specific use:
6204 R1: stack pointer
6205 R2: reserved for system use
6206 R3-R4: parameter passing and return values
6207 R5-R10: parameter passing
6208 R13: small data area pointer
6209 R30: GOT pointer
6210 R31: frame pointer
6211
6212 (U-Boot also uses R12 as internal GOT pointer. r12
6213 is a volatile register so r12 needs to be reset when
6214 going back and forth between asm and C)
6215
6216 ==> U-Boot will use R2 to hold a pointer to the global data
6217
6218 Note: on PPC, we could use a static initializer (since the
6219 address of the global data structure is known at compile time),
6220 but it turned out that reserving a register results in somewhat
6221 smaller code - although the code savings are not that big (on
6222 average for all boards 752 bytes for the whole U-Boot image,
6223 624 text + 127 data).
6224
6225 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
6226 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
6227
6228 ==> U-Boot will use P3 to hold a pointer to the global data
6229
6230 On ARM, the following registers are used:
6231
6232 R0: function argument word/integer result
6233 R1-R3: function argument word
6234 R9: platform specific
6235 R10: stack limit (used only if stack checking is enabled)
6236 R11: argument (frame) pointer
6237 R12: temporary workspace
6238 R13: stack pointer
6239 R14: link register
6240 R15: program counter
6241
6242 ==> U-Boot will use R9 to hold a pointer to the global data
6243
6244 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
6245
6246 On Nios II, the ABI is documented here:
6247 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
6248
6249 ==> U-Boot will use gp to hold a pointer to the global data
6250
6251 Note: on Nios II, we give "-G0" option to gcc and don't use gp
6252 to access small data sections, so gp is free.
6253
6254 On NDS32, the following registers are used:
6255
6256 R0-R1: argument/return
6257 R2-R5: argument
6258 R15: temporary register for assembler
6259 R16: trampoline register
6260 R28: frame pointer (FP)
6261 R29: global pointer (GP)
6262 R30: link register (LP)
6263 R31: stack pointer (SP)
6264 PC: program counter (PC)
6265
6266 ==> U-Boot will use R10 to hold a pointer to the global data
6267
6268 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
6269 or current versions of GCC may "optimize" the code too much.
6270
6271 Memory Management:
6272 ------------------
6273
6274 U-Boot runs in system state and uses physical addresses, i.e. the
6275 MMU is not used either for address mapping nor for memory protection.
6276
6277 The available memory is mapped to fixed addresses using the memory
6278 controller. In this process, a contiguous block is formed for each
6279 memory type (Flash, SDRAM, SRAM), even when it consists of several
6280 physical memory banks.
6281
6282 U-Boot is installed in the first 128 kB of the first Flash bank (on
6283 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
6284 booting and sizing and initializing DRAM, the code relocates itself
6285 to the upper end of DRAM. Immediately below the U-Boot code some
6286 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
6287 configuration setting]. Below that, a structure with global Board
6288 Info data is placed, followed by the stack (growing downward).
6289
6290 Additionally, some exception handler code is copied to the low 8 kB
6291 of DRAM (0x00000000 ... 0x00001FFF).
6292
6293 So a typical memory configuration with 16 MB of DRAM could look like
6294 this:
6295
6296 0x0000 0000 Exception Vector code
6297 :
6298 0x0000 1FFF
6299 0x0000 2000 Free for Application Use
6300 :
6301 :
6302
6303 :
6304 :
6305 0x00FB FF20 Monitor Stack (Growing downward)
6306 0x00FB FFAC Board Info Data and permanent copy of global data
6307 0x00FC 0000 Malloc Arena
6308 :
6309 0x00FD FFFF
6310 0x00FE 0000 RAM Copy of Monitor Code
6311 ... eventually: LCD or video framebuffer
6312 ... eventually: pRAM (Protected RAM - unchanged by reset)
6313 0x00FF FFFF [End of RAM]
6314
6315
6316 System Initialization:
6317 ----------------------
6318
6319 In the reset configuration, U-Boot starts at the reset entry point
6320 (on most PowerPC systems at address 0x00000100). Because of the reset
6321 configuration for CS0# this is a mirror of the onboard Flash memory.
6322 To be able to re-map memory U-Boot then jumps to its link address.
6323 To be able to implement the initialization code in C, a (small!)
6324 initial stack is set up in the internal Dual Ported RAM (in case CPUs
6325 which provide such a feature like MPC8xx or MPC8260), or in a locked
6326 part of the data cache. After that, U-Boot initializes the CPU core,
6327 the caches and the SIU.
6328
6329 Next, all (potentially) available memory banks are mapped using a
6330 preliminary mapping. For example, we put them on 512 MB boundaries
6331 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
6332 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
6333 programmed for SDRAM access. Using the temporary configuration, a
6334 simple memory test is run that determines the size of the SDRAM
6335 banks.
6336
6337 When there is more than one SDRAM bank, and the banks are of
6338 different size, the largest is mapped first. For equal size, the first
6339 bank (CS2#) is mapped first. The first mapping is always for address
6340 0x00000000, with any additional banks following immediately to create
6341 contiguous memory starting from 0.
6342
6343 Then, the monitor installs itself at the upper end of the SDRAM area
6344 and allocates memory for use by malloc() and for the global Board
6345 Info data; also, the exception vector code is copied to the low RAM
6346 pages, and the final stack is set up.
6347
6348 Only after this relocation will you have a "normal" C environment;
6349 until that you are restricted in several ways, mostly because you are
6350 running from ROM, and because the code will have to be relocated to a
6351 new address in RAM.
6352
6353
6354 U-Boot Porting Guide:
6355 ----------------------
6356
6357 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
6358 list, October 2002]
6359
6360
6361 int main(int argc, char *argv[])
6362 {
6363 sighandler_t no_more_time;
6364
6365 signal(SIGALRM, no_more_time);
6366 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
6367
6368 if (available_money > available_manpower) {
6369 Pay consultant to port U-Boot;
6370 return 0;
6371 }
6372
6373 Download latest U-Boot source;
6374
6375 Subscribe to u-boot mailing list;
6376
6377 if (clueless)
6378 email("Hi, I am new to U-Boot, how do I get started?");
6379
6380 while (learning) {
6381 Read the README file in the top level directory;
6382 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
6383 Read applicable doc/*.README;
6384 Read the source, Luke;
6385 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
6386 }
6387
6388 if (available_money > toLocalCurrency ($2500))
6389 Buy a BDI3000;
6390 else
6391 Add a lot of aggravation and time;
6392
6393 if (a similar board exists) { /* hopefully... */
6394 cp -a board/<similar> board/<myboard>
6395 cp include/configs/<similar>.h include/configs/<myboard>.h
6396 } else {
6397 Create your own board support subdirectory;
6398 Create your own board include/configs/<myboard>.h file;
6399 }
6400 Edit new board/<myboard> files
6401 Edit new include/configs/<myboard>.h
6402
6403 while (!accepted) {
6404 while (!running) {
6405 do {
6406 Add / modify source code;
6407 } until (compiles);
6408 Debug;
6409 if (clueless)
6410 email("Hi, I am having problems...");
6411 }
6412 Send patch file to the U-Boot email list;
6413 if (reasonable critiques)
6414 Incorporate improvements from email list code review;
6415 else
6416 Defend code as written;
6417 }
6418
6419 return 0;
6420 }
6421
6422 void no_more_time (int sig)
6423 {
6424 hire_a_guru();
6425 }
6426
6427
6428 Coding Standards:
6429 -----------------
6430
6431 All contributions to U-Boot should conform to the Linux kernel
6432 coding style; see the file "Documentation/CodingStyle" and the script
6433 "scripts/Lindent" in your Linux kernel source directory.
6434
6435 Source files originating from a different project (for example the
6436 MTD subsystem) are generally exempt from these guidelines and are not
6437 reformated to ease subsequent migration to newer versions of those
6438 sources.
6439
6440 Please note that U-Boot is implemented in C (and to some small parts in
6441 Assembler); no C++ is used, so please do not use C++ style comments (//)
6442 in your code.
6443
6444 Please also stick to the following formatting rules:
6445 - remove any trailing white space
6446 - use TAB characters for indentation and vertical alignment, not spaces
6447 - make sure NOT to use DOS '\r\n' line feeds
6448 - do not add more than 2 consecutive empty lines to source files
6449 - do not add trailing empty lines to source files
6450
6451 Submissions which do not conform to the standards may be returned
6452 with a request to reformat the changes.
6453
6454
6455 Submitting Patches:
6456 -------------------
6457
6458 Since the number of patches for U-Boot is growing, we need to
6459 establish some rules. Submissions which do not conform to these rules
6460 may be rejected, even when they contain important and valuable stuff.
6461
6462 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
6463
6464 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
6465 see http://lists.denx.de/mailman/listinfo/u-boot
6466
6467 When you send a patch, please include the following information with
6468 it:
6469
6470 * For bug fixes: a description of the bug and how your patch fixes
6471 this bug. Please try to include a way of demonstrating that the
6472 patch actually fixes something.
6473
6474 * For new features: a description of the feature and your
6475 implementation.
6476
6477 * A CHANGELOG entry as plaintext (separate from the patch)
6478
6479 * For major contributions, your entry to the CREDITS file
6480
6481 * When you add support for a new board, don't forget to add a
6482 maintainer e-mail address to the boards.cfg file, too.
6483
6484 * If your patch adds new configuration options, don't forget to
6485 document these in the README file.
6486
6487 * The patch itself. If you are using git (which is *strongly*
6488 recommended) you can easily generate the patch using the
6489 "git format-patch". If you then use "git send-email" to send it to
6490 the U-Boot mailing list, you will avoid most of the common problems
6491 with some other mail clients.
6492
6493 If you cannot use git, use "diff -purN OLD NEW". If your version of
6494 diff does not support these options, then get the latest version of
6495 GNU diff.
6496
6497 The current directory when running this command shall be the parent
6498 directory of the U-Boot source tree (i. e. please make sure that
6499 your patch includes sufficient directory information for the
6500 affected files).
6501
6502 We prefer patches as plain text. MIME attachments are discouraged,
6503 and compressed attachments must not be used.
6504
6505 * If one logical set of modifications affects or creates several
6506 files, all these changes shall be submitted in a SINGLE patch file.
6507
6508 * Changesets that contain different, unrelated modifications shall be
6509 submitted as SEPARATE patches, one patch per changeset.
6510
6511
6512 Notes:
6513
6514 * Before sending the patch, run the MAKEALL script on your patched
6515 source tree and make sure that no errors or warnings are reported
6516 for any of the boards.
6517
6518 * Keep your modifications to the necessary minimum: A patch
6519 containing several unrelated changes or arbitrary reformats will be
6520 returned with a request to re-formatting / split it.
6521
6522 * If you modify existing code, make sure that your new code does not
6523 add to the memory footprint of the code ;-) Small is beautiful!
6524 When adding new features, these should compile conditionally only
6525 (using #ifdef), and the resulting code with the new feature
6526 disabled must not need more memory than the old code without your
6527 modification.
6528
6529 * Remember that there is a size limit of 100 kB per message on the
6530 u-boot mailing list. Bigger patches will be moderated. If they are
6531 reasonable and not too big, they will be acknowledged. But patches
6532 bigger than the size limit should be avoided.