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c609719b 1#
eca3aeb3 2# (C) Copyright 2000 - 2013
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3# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4#
eca3aeb3 5# SPDX-License-Identifier: GPL-2.0+
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6#
7
8Summary:
9========
10
24ee89b9 11This directory contains the source code for U-Boot, a boot loader for
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12Embedded boards based on PowerPC, ARM, MIPS and several other
13processors, which can be installed in a boot ROM and used to
14initialize and test the hardware or to download and run application
15code.
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16
17The development of U-Boot is closely related to Linux: some parts of
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18the source code originate in the Linux source tree, we have some
19header files in common, and special provision has been made to
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20support booting of Linux images.
21
22Some attention has been paid to make this software easily
23configurable and extendable. For instance, all monitor commands are
24implemented with the same call interface, so that it's very easy to
25add new commands. Also, instead of permanently adding rarely used
26code (for instance hardware test utilities) to the monitor, you can
27load and run it dynamically.
28
29
30Status:
31=======
32
33In general, all boards for which a configuration option exists in the
24ee89b9 34Makefile have been tested to some extent and can be considered
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35"working". In fact, many of them are used in production systems.
36
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37In case of problems see the CHANGELOG file to find out who contributed
38the specific port. In addition, there are various MAINTAINERS files
39scattered throughout the U-Boot source identifying the people or
40companies responsible for various boards and subsystems.
c609719b 41
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42Note: As of August, 2010, there is no longer a CHANGELOG file in the
43actual U-Boot source tree; however, it can be created dynamically
44from the Git log using:
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45
46 make CHANGELOG
47
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48
49Where to get help:
50==================
51
24ee89b9 52In case you have questions about, problems with or contributions for
7207b366 53U-Boot, you should send a message to the U-Boot mailing list at
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54<u-boot@lists.denx.de>. There is also an archive of previous traffic
55on the mailing list - please search the archive before asking FAQ's.
56Please see http://lists.denx.de/pipermail/u-boot and
57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
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58
59
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60Where to get source code:
61=========================
62
7207b366 63The U-Boot source code is maintained in the Git repository at
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64git://www.denx.de/git/u-boot.git ; you can browse it online at
65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
66
67The "snapshot" links on this page allow you to download tarballs of
11ccc33f 68any version you might be interested in. Official releases are also
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69available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
70directory.
71
d4ee711d 72Pre-built (and tested) images are available from
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73ftp://ftp.denx.de/pub/u-boot/images/
74
75
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76Where we come from:
77===================
78
79- start from 8xxrom sources
24ee89b9 80- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
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81- clean up code
82- make it easier to add custom boards
83- make it possible to add other [PowerPC] CPUs
84- extend functions, especially:
85 * Provide extended interface to Linux boot loader
86 * S-Record download
87 * network boot
11ccc33f 88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
24ee89b9 89- create ARMBoot project (http://sourceforge.net/projects/armboot)
c609719b 90- add other CPU families (starting with ARM)
24ee89b9 91- create U-Boot project (http://sourceforge.net/projects/u-boot)
0d28f34b 92- current project page: see http://www.denx.de/wiki/U-Boot
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93
94
95Names and Spelling:
96===================
97
98The "official" name of this project is "Das U-Boot". The spelling
99"U-Boot" shall be used in all written text (documentation, comments
100in source files etc.). Example:
101
102 This is the README file for the U-Boot project.
103
104File names etc. shall be based on the string "u-boot". Examples:
105
106 include/asm-ppc/u-boot.h
107
108 #include <asm/u-boot.h>
109
110Variable names, preprocessor constants etc. shall be either based on
111the string "u_boot" or on "U_BOOT". Example:
112
113 U_BOOT_VERSION u_boot_logo
114 IH_OS_U_BOOT u_boot_hush_start
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115
116
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117Versioning:
118===========
119
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120Starting with the release in October 2008, the names of the releases
121were changed from numerical release numbers without deeper meaning
122into a time stamp based numbering. Regular releases are identified by
123names consisting of the calendar year and month of the release date.
124Additional fields (if present) indicate release candidates or bug fix
125releases in "stable" maintenance trees.
126
127Examples:
c0f40859 128 U-Boot v2009.11 - Release November 2009
360d883a 129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
0de21ecb 130 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
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131
132
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133Directory Hierarchy:
134====================
135
8d321b81 136/arch Architecture specific files
6eae68e4 137 /arc Files generic to ARC architecture
8d321b81 138 /arm Files generic to ARM architecture
8d321b81 139 /m68k Files generic to m68k architecture
8d321b81 140 /microblaze Files generic to microblaze architecture
8d321b81 141 /mips Files generic to MIPS architecture
afc1ce82 142 /nds32 Files generic to NDS32 architecture
8d321b81 143 /nios2 Files generic to Altera NIOS2 architecture
33c7731b 144 /openrisc Files generic to OpenRISC architecture
a47a12be 145 /powerpc Files generic to PowerPC architecture
7207b366 146 /sandbox Files generic to HW-independent "sandbox"
8d321b81 147 /sh Files generic to SH architecture
33c7731b 148 /x86 Files generic to x86 architecture
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149/api Machine/arch independent API for external apps
150/board Board dependent files
740f7e5c 151/cmd U-Boot commands functions
8d321b81 152/common Misc architecture independent functions
7207b366 153/configs Board default configuration files
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154/disk Code for disk drive partition handling
155/doc Documentation (don't expect too much)
156/drivers Commonly used device drivers
33c7731b 157/dts Contains Makefile for building internal U-Boot fdt.
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158/examples Example code for standalone applications, etc.
159/fs Filesystem code (cramfs, ext2, jffs2, etc.)
160/include Header Files
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161/lib Library routines generic to all architectures
162/Licenses Various license files
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163/net Networking code
164/post Power On Self Test
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165/scripts Various build scripts and Makefiles
166/test Various unit test files
8d321b81 167/tools Tools to build S-Record or U-Boot images, etc.
c609719b 168
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169Software Configuration:
170=======================
171
172Configuration is usually done using C preprocessor defines; the
173rationale behind that is to avoid dead code whenever possible.
174
175There are two classes of configuration variables:
176
177* Configuration _OPTIONS_:
178 These are selectable by the user and have names beginning with
179 "CONFIG_".
180
181* Configuration _SETTINGS_:
182 These depend on the hardware etc. and should not be meddled with if
183 you don't know what you're doing; they have names beginning with
6d0f6bcf 184 "CONFIG_SYS_".
c609719b 185
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186Previously, all configuration was done by hand, which involved creating
187symbolic links and editing configuration files manually. More recently,
188U-Boot has added the Kbuild infrastructure used by the Linux kernel,
189allowing you to use the "make menuconfig" command to configure your
190build.
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191
192
193Selection of Processor Architecture and Board Type:
194---------------------------------------------------
195
196For all supported boards there are ready-to-use default
ab584d67 197configurations available; just type "make <board_name>_defconfig".
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198
199Example: For a TQM823L module type:
200
201 cd u-boot
ab584d67 202 make TQM823L_defconfig
c609719b 203
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204Note: If you're looking for the default configuration file for a board
205you're sure used to be there but is now missing, check the file
206doc/README.scrapyard for a list of no longer supported boards.
c609719b 207
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208Sandbox Environment:
209--------------------
210
211U-Boot can be built natively to run on a Linux host using the 'sandbox'
212board. This allows feature development which is not board- or architecture-
213specific to be undertaken on a native platform. The sandbox is also used to
214run some of U-Boot's tests.
215
6b1978f8 216See board/sandbox/README.sandbox for more details.
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217
218
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219Board Initialisation Flow:
220--------------------------
221
222This is the intended start-up flow for boards. This should apply for both
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223SPL and U-Boot proper (i.e. they both follow the same rules).
224
225Note: "SPL" stands for "Secondary Program Loader," which is explained in
226more detail later in this file.
227
228At present, SPL mostly uses a separate code path, but the function names
229and roles of each function are the same. Some boards or architectures
230may not conform to this. At least most ARM boards which use
231CONFIG_SPL_FRAMEWORK conform to this.
232
233Execution typically starts with an architecture-specific (and possibly
234CPU-specific) start.S file, such as:
235
236 - arch/arm/cpu/armv7/start.S
237 - arch/powerpc/cpu/mpc83xx/start.S
238 - arch/mips/cpu/start.S
db910353 239
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240and so on. From there, three functions are called; the purpose and
241limitations of each of these functions are described below.
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242
243lowlevel_init():
244 - purpose: essential init to permit execution to reach board_init_f()
245 - no global_data or BSS
246 - there is no stack (ARMv7 may have one but it will soon be removed)
247 - must not set up SDRAM or use console
248 - must only do the bare minimum to allow execution to continue to
249 board_init_f()
250 - this is almost never needed
251 - return normally from this function
252
253board_init_f():
254 - purpose: set up the machine ready for running board_init_r():
255 i.e. SDRAM and serial UART
256 - global_data is available
257 - stack is in SRAM
258 - BSS is not available, so you cannot use global/static variables,
259 only stack variables and global_data
260
261 Non-SPL-specific notes:
262 - dram_init() is called to set up DRAM. If already done in SPL this
263 can do nothing
264
265 SPL-specific notes:
266 - you can override the entire board_init_f() function with your own
267 version as needed.
268 - preloader_console_init() can be called here in extremis
269 - should set up SDRAM, and anything needed to make the UART work
270 - these is no need to clear BSS, it will be done by crt0.S
271 - must return normally from this function (don't call board_init_r()
272 directly)
273
274Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
275this point the stack and global_data are relocated to below
276CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
277memory.
278
279board_init_r():
280 - purpose: main execution, common code
281 - global_data is available
282 - SDRAM is available
283 - BSS is available, all static/global variables can be used
284 - execution eventually continues to main_loop()
285
286 Non-SPL-specific notes:
287 - U-Boot is relocated to the top of memory and is now running from
288 there.
289
290 SPL-specific notes:
291 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
292 CONFIG_SPL_STACK_R_ADDR points into SDRAM
293 - preloader_console_init() can be called here - typically this is
0680f1b1 294 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
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295 spl_board_init() function containing this call
296 - loads U-Boot or (in falcon mode) Linux
297
298
299
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300Configuration Options:
301----------------------
302
303Configuration depends on the combination of board and CPU type; all
304such information is kept in a configuration file
305"include/configs/<board_name>.h".
306
307Example: For a TQM823L module, all configuration settings are in
308"include/configs/TQM823L.h".
309
310
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311Many of the options are named exactly as the corresponding Linux
312kernel configuration options. The intention is to make it easier to
313build a config tool - later.
314
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315- ARM Platform Bus Type(CCI):
316 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
317 provides full cache coherency between two clusters of multi-core
318 CPUs and I/O coherency for devices and I/O masters
319
320 CONFIG_SYS_FSL_HAS_CCI400
321
322 Defined For SoC that has cache coherent interconnect
323 CCN-400
7f6c2cbc 324
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325 CONFIG_SYS_FSL_HAS_CCN504
326
327 Defined for SoC that has cache coherent interconnect CCN-504
328
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329The following options need to be configured:
330
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331- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
332
333- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
6ccec449 334
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335- Marvell Family Member
336 CONFIG_SYS_MVFS - define it if you want to enable
337 multiple fs option at one time
338 for marvell soc family
339
66412c63 340- 85xx CPU Options:
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341 CONFIG_SYS_PPC64
342
343 Specifies that the core is a 64-bit PowerPC implementation (implements
344 the "64" category of the Power ISA). This is necessary for ePAPR
345 compliance, among other possible reasons.
346
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347 CONFIG_SYS_FSL_TBCLK_DIV
348
349 Defines the core time base clock divider ratio compared to the
350 system clock. On most PQ3 devices this is 8, on newer QorIQ
351 devices it can be 16 or 32. The ratio varies from SoC to Soc.
352
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353 CONFIG_SYS_FSL_PCIE_COMPAT
354
355 Defines the string to utilize when trying to match PCIe device
356 tree nodes for the given platform.
357
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358 CONFIG_SYS_FSL_ERRATUM_A004510
359
360 Enables a workaround for erratum A004510. If set,
361 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
362 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
363
364 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
365 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
366
367 Defines one or two SoC revisions (low 8 bits of SVR)
368 for which the A004510 workaround should be applied.
369
370 The rest of SVR is either not relevant to the decision
371 of whether the erratum is present (e.g. p2040 versus
372 p2041) or is implied by the build target, which controls
373 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
374
375 See Freescale App Note 4493 for more information about
376 this erratum.
377
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378 CONFIG_A003399_NOR_WORKAROUND
379 Enables a workaround for IFC erratum A003399. It is only
b445bbb4 380 required during NOR boot.
74fa22ed 381
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382 CONFIG_A008044_WORKAROUND
383 Enables a workaround for T1040/T1042 erratum A008044. It is only
b445bbb4 384 required during NAND boot and valid for Rev 1.0 SoC revision
9f074e67 385
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386 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
387
388 This is the value to write into CCSR offset 0x18600
389 according to the A004510 workaround.
390
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391 CONFIG_SYS_FSL_DSP_DDR_ADDR
392 This value denotes start offset of DDR memory which is
393 connected exclusively to the DSP cores.
394
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395 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
396 This value denotes start offset of M2 memory
397 which is directly connected to the DSP core.
398
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399 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
400 This value denotes start offset of M3 memory which is directly
401 connected to the DSP core.
402
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403 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
404 This value denotes start offset of DSP CCSR space.
405
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406 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
407 Single Source Clock is clocking mode present in some of FSL SoC's.
408 In this mode, a single differential clock is used to supply
409 clocks to the sysclock, ddrclock and usbclock.
410
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411 CONFIG_SYS_CPC_REINIT_F
412 This CONFIG is defined when the CPC is configured as SRAM at the
a187559e 413 time of U-Boot entry and is required to be re-initialized.
fb4a2409 414
aade2004 415 CONFIG_DEEP_SLEEP
b445bbb4 416 Indicates this SoC supports deep sleep feature. If deep sleep is
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417 supported, core will start to execute uboot when wakes up.
418
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419- Generic CPU options:
420 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
421
422 Defines the endianess of the CPU. Implementation of those
423 values is arch specific.
424
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425 CONFIG_SYS_FSL_DDR
426 Freescale DDR driver in use. This type of DDR controller is
427 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
428 SoCs.
429
430 CONFIG_SYS_FSL_DDR_ADDR
431 Freescale DDR memory-mapped register base.
432
433 CONFIG_SYS_FSL_DDR_EMU
434 Specify emulator support for DDR. Some DDR features such as
435 deskew training are not available.
436
437 CONFIG_SYS_FSL_DDRC_GEN1
438 Freescale DDR1 controller.
439
440 CONFIG_SYS_FSL_DDRC_GEN2
441 Freescale DDR2 controller.
442
443 CONFIG_SYS_FSL_DDRC_GEN3
444 Freescale DDR3 controller.
445
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446 CONFIG_SYS_FSL_DDRC_GEN4
447 Freescale DDR4 controller.
448
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449 CONFIG_SYS_FSL_DDRC_ARM_GEN3
450 Freescale DDR3 controller for ARM-based SoCs.
451
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452 CONFIG_SYS_FSL_DDR1
453 Board config to use DDR1. It can be enabled for SoCs with
454 Freescale DDR1 or DDR2 controllers, depending on the board
455 implemetation.
456
457 CONFIG_SYS_FSL_DDR2
62a3b7dd 458 Board config to use DDR2. It can be enabled for SoCs with
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459 Freescale DDR2 or DDR3 controllers, depending on the board
460 implementation.
461
462 CONFIG_SYS_FSL_DDR3
463 Board config to use DDR3. It can be enabled for SoCs with
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464 Freescale DDR3 or DDR3L controllers.
465
466 CONFIG_SYS_FSL_DDR3L
467 Board config to use DDR3L. It can be enabled for SoCs with
468 DDR3L controllers.
469
470 CONFIG_SYS_FSL_DDR4
471 Board config to use DDR4. It can be enabled for SoCs with
472 DDR4 controllers.
5614e71b 473
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474 CONFIG_SYS_FSL_IFC_BE
475 Defines the IFC controller register space as Big Endian
476
477 CONFIG_SYS_FSL_IFC_LE
478 Defines the IFC controller register space as Little Endian
479
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480 CONFIG_SYS_FSL_IFC_CLK_DIV
481 Defines divider of platform clock(clock input to IFC controller).
482
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483 CONFIG_SYS_FSL_LBC_CLK_DIV
484 Defines divider of platform clock(clock input to eLBC controller).
485
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486 CONFIG_SYS_FSL_PBL_PBI
487 It enables addition of RCW (Power on reset configuration) in built image.
488 Please refer doc/README.pblimage for more details
489
490 CONFIG_SYS_FSL_PBL_RCW
491 It adds PBI(pre-boot instructions) commands in u-boot build image.
492 PBI commands can be used to configure SoC before it starts the execution.
493 Please refer doc/README.pblimage for more details
494
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495 CONFIG_SPL_FSL_PBL
496 It adds a target to create boot binary having SPL binary in PBI format
497 concatenated with u-boot binary.
498
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499 CONFIG_SYS_FSL_DDR_BE
500 Defines the DDR controller register space as Big Endian
501
502 CONFIG_SYS_FSL_DDR_LE
503 Defines the DDR controller register space as Little Endian
504
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505 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
506 Physical address from the view of DDR controllers. It is the
507 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
508 it could be different for ARM SoCs.
509
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510 CONFIG_SYS_FSL_DDR_INTLV_256B
511 DDR controller interleaving on 256-byte. This is a special
512 interleaving mode, handled by Dickens for Freescale layerscape
513 SoCs with ARM core.
514
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515 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
516 Number of controllers used as main memory.
517
518 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
519 Number of controllers used for other than main memory.
520
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521 CONFIG_SYS_FSL_HAS_DP_DDR
522 Defines the SoC has DP-DDR used for DPAA.
523
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524 CONFIG_SYS_FSL_SEC_BE
525 Defines the SEC controller register space as Big Endian
526
527 CONFIG_SYS_FSL_SEC_LE
528 Defines the SEC controller register space as Little Endian
529
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530- MIPS CPU options:
531 CONFIG_SYS_INIT_SP_OFFSET
532
533 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
534 pointer. This is needed for the temporary stack before
535 relocation.
536
537 CONFIG_SYS_MIPS_CACHE_MODE
538
539 Cache operation mode for the MIPS CPU.
540 See also arch/mips/include/asm/mipsregs.h.
541 Possible values are:
542 CONF_CM_CACHABLE_NO_WA
543 CONF_CM_CACHABLE_WA
544 CONF_CM_UNCACHED
545 CONF_CM_CACHABLE_NONCOHERENT
546 CONF_CM_CACHABLE_CE
547 CONF_CM_CACHABLE_COW
548 CONF_CM_CACHABLE_CUW
549 CONF_CM_CACHABLE_ACCELERATED
550
551 CONFIG_SYS_XWAY_EBU_BOOTCFG
552
553 Special option for Lantiq XWAY SoCs for booting from NOR flash.
554 See also arch/mips/cpu/mips32/start.S.
555
556 CONFIG_XWAY_SWAP_BYTES
557
558 Enable compilation of tools/xway-swap-bytes needed for Lantiq
559 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
560 be swapped if a flash programmer is used.
561
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562- ARM options:
563 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
564
565 Select high exception vectors of the ARM core, e.g., do not
566 clear the V bit of the c1 register of CP15.
567
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568 COUNTER_FREQUENCY
569 Generic timer clock source frequency.
570
571 COUNTER_FREQUENCY_REAL
572 Generic timer clock source frequency if the real clock is
573 different from COUNTER_FREQUENCY, and can only be determined
574 at run time.
575
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576- Tegra SoC options:
577 CONFIG_TEGRA_SUPPORT_NON_SECURE
578
579 Support executing U-Boot in non-secure (NS) mode. Certain
580 impossible actions will be skipped if the CPU is in NS mode,
581 such as ARM architectural timer initialization.
582
5da627a4 583- Linux Kernel Interface:
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584 CONFIG_CLOCKS_IN_MHZ
585
586 U-Boot stores all clock information in Hz
587 internally. For binary compatibility with older Linux
588 kernels (which expect the clocks passed in the
589 bd_info data to be in MHz) the environment variable
590 "clocks_in_mhz" can be defined so that U-Boot
591 converts clock data to MHZ before passing it to the
592 Linux kernel.
c609719b 593 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
218ca724 594 "clocks_in_mhz=1" is automatically included in the
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595 default environment.
596
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597 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
598
b445bbb4 599 When transferring memsize parameter to Linux, some versions
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600 expect it to be in bytes, others in MB.
601 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
602
fec6d9ee 603 CONFIG_OF_LIBFDT
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604
605 New kernel versions are expecting firmware settings to be
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606 passed using flattened device trees (based on open firmware
607 concepts).
608
609 CONFIG_OF_LIBFDT
610 * New libfdt-based support
611 * Adds the "fdt" command
3bb342fc 612 * The bootm command automatically updates the fdt
213bf8c8 613
f57f70aa 614 OF_TBCLK - The timebase frequency.
c2871f03 615 OF_STDOUT_PATH - The path to the console device
f57f70aa 616
11ccc33f
MZ
617 boards with QUICC Engines require OF_QE to set UCC MAC
618 addresses
3bb342fc 619
4e253137
KG
620 CONFIG_OF_BOARD_SETUP
621
622 Board code has addition modification that it wants to make
623 to the flat device tree before handing it off to the kernel
f57f70aa 624
c654b517
SG
625 CONFIG_OF_SYSTEM_SETUP
626
627 Other code has addition modification that it wants to make
628 to the flat device tree before handing it off to the kernel.
629 This causes ft_system_setup() to be called before booting
630 the kernel.
631
3887c3fb
HS
632 CONFIG_OF_IDE_FIXUP
633
634 U-Boot can detect if an IDE device is present or not.
635 If not, and this new config option is activated, U-Boot
636 removes the ATA node from the DTS before booting Linux,
637 so the Linux IDE driver does not probe the device and
638 crash. This is needed for buggy hardware (uc101) where
639 no pull down resistor is connected to the signal IDE5V_DD7.
640
7eb29398
IG
641 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
642
643 This setting is mandatory for all boards that have only one
644 machine type and must be used to specify the machine type
645 number as it appears in the ARM machine registry
646 (see http://www.arm.linux.org.uk/developer/machines/).
647 Only boards that have multiple machine types supported
648 in a single configuration file and the machine type is
649 runtime discoverable, do not have to use this setting.
650
0b2f4eca
NG
651- vxWorks boot parameters:
652
653 bootvx constructs a valid bootline using the following
9e98b7e3
BM
654 environments variables: bootdev, bootfile, ipaddr, netmask,
655 serverip, gatewayip, hostname, othbootargs.
0b2f4eca
NG
656 It loads the vxWorks image pointed bootfile.
657
0b2f4eca
NG
658 Note: If a "bootargs" environment is defined, it will overwride
659 the defaults discussed just above.
660
2c451f78
A
661- Cache Configuration:
662 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
663 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
664 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
665
93bc2193
A
666- Cache Configuration for ARM:
667 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
668 controller
669 CONFIG_SYS_PL310_BASE - Physical base address of PL310
670 controller register space
671
6705d81e 672- Serial Ports:
48d0192f 673 CONFIG_PL010_SERIAL
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WD
674
675 Define this if you want support for Amba PrimeCell PL010 UARTs.
676
48d0192f 677 CONFIG_PL011_SERIAL
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678
679 Define this if you want support for Amba PrimeCell PL011 UARTs.
680
681 CONFIG_PL011_CLOCK
682
683 If you have Amba PrimeCell PL011 UARTs, set this variable to
684 the clock speed of the UARTs.
685
686 CONFIG_PL01x_PORTS
687
688 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
689 define this to a list of base addresses for each (supported)
690 port. See e.g. include/configs/versatile.h
691
d57dee57
KM
692 CONFIG_SERIAL_HW_FLOW_CONTROL
693
694 Define this variable to enable hw flow control in serial driver.
695 Current user of this option is drivers/serial/nsl16550.c driver
6705d81e 696
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697- Console Baudrate:
698 CONFIG_BAUDRATE - in bps
699 Select one of the baudrates listed in
6d0f6bcf 700 CONFIG_SYS_BAUDRATE_TABLE, see below.
c609719b 701
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WD
702- Autoboot Command:
703 CONFIG_BOOTCOMMAND
704 Only needed when CONFIG_BOOTDELAY is enabled;
705 define a command string that is automatically executed
706 when no character is read on the console interface
707 within "Boot Delay" after reset.
708
c609719b 709 CONFIG_RAMBOOT and CONFIG_NFSBOOT
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710 The value of these goes into the environment as
711 "ramboot" and "nfsboot" respectively, and can be used
712 as a convenience, when switching between booting from
11ccc33f 713 RAM and NFS.
c609719b 714
eda0ba38
HS
715- Bootcount:
716 CONFIG_BOOTCOUNT_LIMIT
717 Implements a mechanism for detecting a repeating reboot
718 cycle, see:
719 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
720
721 CONFIG_BOOTCOUNT_ENV
722 If no softreset save registers are found on the hardware
723 "bootcount" is stored in the environment. To prevent a
724 saveenv on all reboots, the environment variable
725 "upgrade_available" is used. If "upgrade_available" is
726 0, "bootcount" is always 0, if "upgrade_available" is
727 1 "bootcount" is incremented in the environment.
728 So the Userspace Applikation must set the "upgrade_available"
729 and "bootcount" variable to 0, if a boot was successfully.
730
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731- Pre-Boot Commands:
732 CONFIG_PREBOOT
733
734 When this option is #defined, the existence of the
735 environment variable "preboot" will be checked
736 immediately before starting the CONFIG_BOOTDELAY
737 countdown and/or running the auto-boot command resp.
738 entering interactive mode.
739
740 This feature is especially useful when "preboot" is
741 automatically generated or modified. For an example
742 see the LWMON board specific code: here "preboot" is
743 modified when the user holds down a certain
744 combination of keys on the (special) keyboard when
745 booting the systems
746
747- Serial Download Echo Mode:
748 CONFIG_LOADS_ECHO
749 If defined to 1, all characters received during a
750 serial download (using the "loads" command) are
751 echoed back. This might be needed by some terminal
752 emulations (like "cu"), but may as well just take
753 time on others. This setting #define's the initial
754 value of the "loads_echo" environment variable.
755
602ad3b3 756- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
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757 CONFIG_KGDB_BAUDRATE
758 Select one of the baudrates listed in
6d0f6bcf 759 CONFIG_SYS_BAUDRATE_TABLE, see below.
c609719b 760
302a6487
SG
761- Removal of commands
762 If no commands are needed to boot, you can disable
763 CONFIG_CMDLINE to remove them. In this case, the command line
764 will not be available, and when U-Boot wants to execute the
765 boot command (on start-up) it will call board_run_command()
766 instead. This can reduce image size significantly for very
767 simple boot procedures.
768
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769- Regular expression support:
770 CONFIG_REGEX
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771 If this variable is defined, U-Boot is linked against
772 the SLRE (Super Light Regular Expression) library,
773 which adds regex support to some commands, as for
774 example "env grep" and "setexpr".
a5ecbe62 775
45ba8077
SG
776- Device tree:
777 CONFIG_OF_CONTROL
778 If this variable is defined, U-Boot will use a device tree
779 to configure its devices, instead of relying on statically
780 compiled #defines in the board file. This option is
781 experimental and only available on a few boards. The device
782 tree is available in the global data as gd->fdt_blob.
783
2c0f79e4 784 U-Boot needs to get its device tree from somewhere. This can
82f766d1 785 be done using one of the three options below:
bbb0b128
SG
786
787 CONFIG_OF_EMBED
788 If this variable is defined, U-Boot will embed a device tree
789 binary in its image. This device tree file should be in the
790 board directory and called <soc>-<board>.dts. The binary file
791 is then picked up in board_init_f() and made available through
eb3eb602 792 the global data structure as gd->fdt_blob.
45ba8077 793
2c0f79e4
SG
794 CONFIG_OF_SEPARATE
795 If this variable is defined, U-Boot will build a device tree
796 binary. It will be called u-boot.dtb. Architecture-specific
797 code will locate it at run-time. Generally this works by:
798
799 cat u-boot.bin u-boot.dtb >image.bin
800
801 and in fact, U-Boot does this for you, creating a file called
802 u-boot-dtb.bin which is useful in the common case. You can
803 still use the individual files if you need something more
804 exotic.
805
82f766d1
AD
806 CONFIG_OF_BOARD
807 If this variable is defined, U-Boot will use the device tree
808 provided by the board at runtime instead of embedding one with
809 the image. Only boards defining board_fdt_blob_setup() support
810 this option (see include/fdtdec.h file).
811
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812- Watchdog:
813 CONFIG_WATCHDOG
814 If this variable is defined, it enables watchdog
6abe6fb6 815 support for the SoC. There must be support in the SoC
907208c4
CL
816 specific code for a watchdog. For the 8xx
817 CPUs, the SIU Watchdog feature is enabled in the SYPCR
818 register. When supported for a specific SoC is
819 available, then no further board specific code should
820 be needed to use it.
6abe6fb6
DZ
821
822 CONFIG_HW_WATCHDOG
823 When using a watchdog circuitry external to the used
824 SoC, then define this variable and provide board
825 specific code for the "hw_watchdog_reset" function.
c609719b 826
7bae0d6f
HS
827 CONFIG_AT91_HW_WDT_TIMEOUT
828 specify the timeout in seconds. default 2 seconds.
829
c1551ea8
SR
830- U-Boot Version:
831 CONFIG_VERSION_VARIABLE
832 If this variable is defined, an environment variable
833 named "ver" is created by U-Boot showing the U-Boot
834 version as printed by the "version" command.
a1ea8e51
BT
835 Any change to this variable will be reverted at the
836 next reset.
c1551ea8 837
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WD
838- Real-Time Clock:
839
602ad3b3 840 When CONFIG_CMD_DATE is selected, the type of the RTC
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WD
841 has to be selected, too. Define exactly one of the
842 following options:
843
c609719b 844 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
4e8b7544 845 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
c609719b 846 CONFIG_RTC_MC146818 - use MC146818 RTC
1cb8e980 847 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
c609719b 848 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
7f70e853 849 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
412921d2 850 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
3bac3513 851 CONFIG_RTC_DS164x - use Dallas DS164x RTC
9536dfcc 852 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
4c0d4c3b 853 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
2bd3cab3 854 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
71d19f30
HS
855 CONFIG_SYS_RV3029_TCR - enable trickle charger on
856 RV3029 RTC.
c609719b 857
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WD
858 Note that if the RTC uses I2C, then the I2C interface
859 must also be configured. See I2C Support, below.
860
e92739d3
PT
861- GPIO Support:
862 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
e92739d3 863
5dec49ca
CP
864 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
865 chip-ngpio pairs that tell the PCA953X driver the number of
866 pins supported by a particular chip.
867
e92739d3
PT
868 Note that if the GPIO device uses I2C, then the I2C interface
869 must also be configured. See I2C Support, below.
870
aa53233a
SG
871- I/O tracing:
872 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
873 accesses and can checksum them or write a list of them out
874 to memory. See the 'iotrace' command for details. This is
875 useful for testing device drivers since it can confirm that
876 the driver behaves the same way before and after a code
877 change. Currently this is supported on sandbox and arm. To
878 add support for your architecture, add '#include <iotrace.h>'
879 to the bottom of arch/<arch>/include/asm/io.h and test.
880
881 Example output from the 'iotrace stats' command is below.
882 Note that if the trace buffer is exhausted, the checksum will
883 still continue to operate.
884
885 iotrace is enabled
886 Start: 10000000 (buffer start address)
887 Size: 00010000 (buffer size)
888 Offset: 00000120 (current buffer offset)
889 Output: 10000120 (start + offset)
890 Count: 00000018 (number of trace records)
891 CRC32: 9526fb66 (CRC32 of all trace records)
892
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WD
893- Timestamp Support:
894
43d9616c
WD
895 When CONFIG_TIMESTAMP is selected, the timestamp
896 (date and time) of an image is printed by image
897 commands like bootm or iminfo. This option is
602ad3b3 898 automatically enabled when you select CONFIG_CMD_DATE .
c609719b 899
923c46f9
KP
900- Partition Labels (disklabels) Supported:
901 Zero or more of the following:
902 CONFIG_MAC_PARTITION Apple's MacOS partition table.
923c46f9
KP
903 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
904 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
905 bootloader. Note 2TB partition limit; see
906 disk/part_efi.c
907 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
c609719b 908
fc843a02 909 If IDE or SCSI support is enabled (CONFIG_IDE or
c649e3c9 910 CONFIG_SCSI) you must configure support for at
923c46f9 911 least one non-MTD partition type as well.
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WD
912
913- IDE Reset method:
4d13cbad
WD
914 CONFIG_IDE_RESET_ROUTINE - this is defined in several
915 board configurations files but used nowhere!
c609719b 916
4d13cbad
WD
917 CONFIG_IDE_RESET - is this is defined, IDE Reset will
918 be performed by calling the function
919 ide_set_reset(int reset)
920 which has to be defined in a board specific file
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WD
921
922- ATAPI Support:
923 CONFIG_ATAPI
924
925 Set this to enable ATAPI support.
926
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WD
927- LBA48 Support
928 CONFIG_LBA48
929
930 Set this to enable support for disks larger than 137GB
4b142feb 931 Also look at CONFIG_SYS_64BIT_LBA.
c40b2956
WD
932 Whithout these , LBA48 support uses 32bit variables and will 'only'
933 support disks up to 2.1TB.
934
6d0f6bcf 935 CONFIG_SYS_64BIT_LBA:
c40b2956
WD
936 When enabled, makes the IDE subsystem use 64bit sector addresses.
937 Default is 32bit.
938
c609719b 939- SCSI Support:
6d0f6bcf
JCPV
940 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
941 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
942 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
c609719b
WD
943 maximum numbers of LUNs, SCSI ID's and target
944 devices.
c609719b 945
93e14596
WD
946 The environment variable 'scsidevs' is set to the number of
947 SCSI devices found during the last scan.
447c031b 948
c609719b 949- NETWORK Support (PCI):
682011ff 950 CONFIG_E1000
ce5207e1
KM
951 Support for Intel 8254x/8257x gigabit chips.
952
953 CONFIG_E1000_SPI
954 Utility code for direct access to the SPI bus on Intel 8257x.
955 This does not do anything useful unless you set at least one
956 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
957
958 CONFIG_E1000_SPI_GENERIC
959 Allow generic access to the SPI bus on the Intel 8257x, for
960 example with the "sspi" command.
961
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WD
962 CONFIG_EEPRO100
963 Support for Intel 82557/82559/82559ER chips.
11ccc33f 964 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
c609719b
WD
965 write routine for first time initialisation.
966
967 CONFIG_TULIP
968 Support for Digital 2114x chips.
969 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
970 modem chip initialisation (KS8761/QS6611).
971
972 CONFIG_NATSEMI
973 Support for National dp83815 chips.
974
975 CONFIG_NS8382X
976 Support for National dp8382[01] gigabit chips.
977
45219c46
WD
978- NETWORK Support (other):
979
c041e9d2
JS
980 CONFIG_DRIVER_AT91EMAC
981 Support for AT91RM9200 EMAC.
982
983 CONFIG_RMII
984 Define this to use reduced MII inteface
985
986 CONFIG_DRIVER_AT91EMAC_QUIET
987 If this defined, the driver is quiet.
988 The driver doen't show link status messages.
989
efdd7319
RH
990 CONFIG_CALXEDA_XGMAC
991 Support for the Calxeda XGMAC device
992
3bb46d23 993 CONFIG_LAN91C96
45219c46
WD
994 Support for SMSC's LAN91C96 chips.
995
45219c46
WD
996 CONFIG_LAN91C96_USE_32_BIT
997 Define this to enable 32 bit addressing
998
3bb46d23 999 CONFIG_SMC91111
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WD
1000 Support for SMSC's LAN91C111 chip
1001
1002 CONFIG_SMC91111_BASE
1003 Define this to hold the physical address
1004 of the device (I/O space)
1005
1006 CONFIG_SMC_USE_32_BIT
1007 Define this if data bus is 32 bits
1008
1009 CONFIG_SMC_USE_IOFUNCS
1010 Define this to use i/o functions instead of macros
1011 (some hardware wont work with macros)
1012
dc02bada
HS
1013 CONFIG_DRIVER_TI_EMAC
1014 Support for davinci emac
1015
1016 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1017 Define this if you have more then 3 PHYs.
1018
b3dbf4a5
ML
1019 CONFIG_FTGMAC100
1020 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1021
1022 CONFIG_FTGMAC100_EGIGA
1023 Define this to use GE link update with gigabit PHY.
1024 Define this if FTGMAC100 is connected to gigabit PHY.
1025 If your system has 10/100 PHY only, it might not occur
1026 wrong behavior. Because PHY usually return timeout or
1027 useless data when polling gigabit status and gigabit
1028 control registers. This behavior won't affect the
1029 correctnessof 10/100 link speed update.
1030
c2fff331 1031 CONFIG_SMC911X
557b377d
JG
1032 Support for SMSC's LAN911x and LAN921x chips
1033
c2fff331 1034 CONFIG_SMC911X_BASE
557b377d
JG
1035 Define this to hold the physical address
1036 of the device (I/O space)
1037
c2fff331 1038 CONFIG_SMC911X_32_BIT
557b377d
JG
1039 Define this if data bus is 32 bits
1040
c2fff331 1041 CONFIG_SMC911X_16_BIT
557b377d
JG
1042 Define this if data bus is 16 bits. If your processor
1043 automatically converts one 32 bit word to two 16 bit
c2fff331 1044 words you may also try CONFIG_SMC911X_32_BIT.
557b377d 1045
3d0075fa
YS
1046 CONFIG_SH_ETHER
1047 Support for Renesas on-chip Ethernet controller
1048
1049 CONFIG_SH_ETHER_USE_PORT
1050 Define the number of ports to be used
1051
1052 CONFIG_SH_ETHER_PHY_ADDR
1053 Define the ETH PHY's address
1054
68260aab
YS
1055 CONFIG_SH_ETHER_CACHE_WRITEBACK
1056 If this option is set, the driver enables cache flush.
1057
b2f97cf2
HS
1058- PWM Support:
1059 CONFIG_PWM_IMX
5052e819 1060 Support for PWM module on the imx6.
b2f97cf2 1061
5e124724 1062- TPM Support:
90899cc0
CC
1063 CONFIG_TPM
1064 Support TPM devices.
1065
0766ad2f
CR
1066 CONFIG_TPM_TIS_INFINEON
1067 Support for Infineon i2c bus TPM devices. Only one device
1b393db5
TWHT
1068 per system is supported at this time.
1069
1b393db5
TWHT
1070 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1071 Define the burst count bytes upper limit
1072
3aa74088
CR
1073 CONFIG_TPM_ST33ZP24
1074 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
1075
1076 CONFIG_TPM_ST33ZP24_I2C
1077 Support for STMicroelectronics ST33ZP24 I2C devices.
1078 Requires TPM_ST33ZP24 and I2C.
1079
b75fdc11
CR
1080 CONFIG_TPM_ST33ZP24_SPI
1081 Support for STMicroelectronics ST33ZP24 SPI devices.
1082 Requires TPM_ST33ZP24 and SPI.
1083
c01939c7
DE
1084 CONFIG_TPM_ATMEL_TWI
1085 Support for Atmel TWI TPM device. Requires I2C support.
1086
90899cc0 1087 CONFIG_TPM_TIS_LPC
5e124724
VB
1088 Support for generic parallel port TPM devices. Only one device
1089 per system is supported at this time.
1090
1091 CONFIG_TPM_TIS_BASE_ADDRESS
1092 Base address where the generic TPM device is mapped
1093 to. Contemporary x86 systems usually map it at
1094 0xfed40000.
1095
be6c1529
RP
1096 CONFIG_TPM
1097 Define this to enable the TPM support library which provides
1098 functional interfaces to some TPM commands.
1099 Requires support for a TPM device.
1100
1101 CONFIG_TPM_AUTH_SESSIONS
1102 Define this to enable authorized functions in the TPM library.
1103 Requires CONFIG_TPM and CONFIG_SHA1.
1104
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WD
1105- USB Support:
1106 At the moment only the UHCI host controller is
064b55cf 1107 supported (PIP405, MIP405); define
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WD
1108 CONFIG_USB_UHCI to enable it.
1109 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
30d56fae 1110 and define CONFIG_USB_STORAGE to enable the USB
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WD
1111 storage devices.
1112 Note:
1113 Supported are USB Keyboards and USB Floppy drives
1114 (TEAC FD-05PUB).
4d13cbad 1115
9ab4ce22
SG
1116 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1117 txfilltuning field in the EHCI controller on reset.
1118
6e9e0626
OT
1119 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1120 HW module registers.
1121
16c8d5e7
WD
1122- USB Device:
1123 Define the below if you wish to use the USB console.
1124 Once firmware is rebuilt from a serial console issue the
1125 command "setenv stdin usbtty; setenv stdout usbtty" and
11ccc33f 1126 attach your USB cable. The Unix command "dmesg" should print
16c8d5e7
WD
1127 it has found a new device. The environment variable usbtty
1128 can be set to gserial or cdc_acm to enable your device to
386eda02 1129 appear to a USB host as a Linux gserial device or a
16c8d5e7
WD
1130 Common Device Class Abstract Control Model serial device.
1131 If you select usbtty = gserial you should be able to enumerate
1132 a Linux host by
1133 # modprobe usbserial vendor=0xVendorID product=0xProductID
1134 else if using cdc_acm, simply setting the environment
1135 variable usbtty to be cdc_acm should suffice. The following
1136 might be defined in YourBoardName.h
386eda02 1137
16c8d5e7
WD
1138 CONFIG_USB_DEVICE
1139 Define this to build a UDC device
1140
1141 CONFIG_USB_TTY
1142 Define this to have a tty type of device available to
1143 talk to the UDC device
386eda02 1144
f9da0f89
VK
1145 CONFIG_USBD_HS
1146 Define this to enable the high speed support for usb
1147 device and usbtty. If this feature is enabled, a routine
1148 int is_usbd_high_speed(void)
1149 also needs to be defined by the driver to dynamically poll
1150 whether the enumeration has succeded at high speed or full
1151 speed.
1152
6d0f6bcf 1153 CONFIG_SYS_CONSOLE_IS_IN_ENV
16c8d5e7
WD
1154 Define this if you want stdin, stdout &/or stderr to
1155 be set to usbtty.
1156
386eda02 1157 If you have a USB-IF assigned VendorID then you may wish to
16c8d5e7 1158 define your own vendor specific values either in BoardName.h
386eda02 1159 or directly in usbd_vendor_info.h. If you don't define
16c8d5e7
WD
1160 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1161 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1162 should pretend to be a Linux device to it's target host.
1163
1164 CONFIG_USBD_MANUFACTURER
1165 Define this string as the name of your company for
1166 - CONFIG_USBD_MANUFACTURER "my company"
386eda02 1167
16c8d5e7
WD
1168 CONFIG_USBD_PRODUCT_NAME
1169 Define this string as the name of your product
1170 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1171
1172 CONFIG_USBD_VENDORID
1173 Define this as your assigned Vendor ID from the USB
1174 Implementors Forum. This *must* be a genuine Vendor ID
1175 to avoid polluting the USB namespace.
1176 - CONFIG_USBD_VENDORID 0xFFFF
386eda02 1177
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WD
1178 CONFIG_USBD_PRODUCTID
1179 Define this as the unique Product ID
1180 for your device
1181 - CONFIG_USBD_PRODUCTID 0xFFFF
4d13cbad 1182
d70a560f
IG
1183- ULPI Layer Support:
1184 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1185 the generic ULPI layer. The generic layer accesses the ULPI PHY
1186 via the platform viewport, so you need both the genric layer and
1187 the viewport enabled. Currently only Chipidea/ARC based
1188 viewport is supported.
1189 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1190 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
6d365ea0
LS
1191 If your ULPI phy needs a different reference clock than the
1192 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1193 the appropriate value in Hz.
c609719b 1194
71f95118 1195- MMC Support:
8bde7f77
WD
1196 The MMC controller on the Intel PXA is supported. To
1197 enable this define CONFIG_MMC. The MMC can be
1198 accessed from the boot prompt by mapping the device
71f95118 1199 to physical memory similar to flash. Command line is
602ad3b3
JL
1200 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1201 the FAT fs. This is enabled with CONFIG_CMD_FAT.
71f95118 1202
afb35666
YS
1203 CONFIG_SH_MMCIF
1204 Support for Renesas on-chip MMCIF controller
1205
1206 CONFIG_SH_MMCIF_ADDR
1207 Define the base address of MMCIF registers
1208
1209 CONFIG_SH_MMCIF_CLK
1210 Define the clock frequency for MMCIF
1211
1fd93c6e
PA
1212 CONFIG_SUPPORT_EMMC_BOOT
1213 Enable some additional features of the eMMC boot partitions.
1214
1215 CONFIG_SUPPORT_EMMC_RPMB
1216 Enable the commands for reading, writing and programming the
1217 key for the Replay Protection Memory Block partition in eMMC.
1218
b3ba6e94 1219- USB Device Firmware Update (DFU) class support:
01acd6ab 1220 CONFIG_USB_FUNCTION_DFU
b3ba6e94
TR
1221 This enables the USB portion of the DFU USB class
1222
b3ba6e94
TR
1223 CONFIG_DFU_MMC
1224 This enables support for exposing (e)MMC devices via DFU.
1225
c6631764
PA
1226 CONFIG_DFU_NAND
1227 This enables support for exposing NAND devices via DFU.
1228
a9479f04
AM
1229 CONFIG_DFU_RAM
1230 This enables support for exposing RAM via DFU.
1231 Note: DFU spec refer to non-volatile memory usage, but
1232 allow usages beyond the scope of spec - here RAM usage,
1233 one that would help mostly the developer.
1234
e7e75c70
HS
1235 CONFIG_SYS_DFU_DATA_BUF_SIZE
1236 Dfu transfer uses a buffer before writing data to the
1237 raw storage device. Make the size (in bytes) of this buffer
1238 configurable. The size of this buffer is also configurable
1239 through the "dfu_bufsiz" environment variable.
1240
ea2453d5
PA
1241 CONFIG_SYS_DFU_MAX_FILE_SIZE
1242 When updating files rather than the raw storage device,
1243 we use a static buffer to copy the file into and then write
1244 the buffer once we've been given the whole file. Define
1245 this to the maximum filesize (in bytes) for the buffer.
1246 Default is 4 MiB if undefined.
1247
001a8319
HS
1248 DFU_DEFAULT_POLL_TIMEOUT
1249 Poll timeout [ms], is the timeout a device can send to the
1250 host. The host must wait for this timeout before sending
1251 a subsequent DFU_GET_STATUS request to the device.
1252
1253 DFU_MANIFEST_POLL_TIMEOUT
1254 Poll timeout [ms], which the device sends to the host when
1255 entering dfuMANIFEST state. Host waits this timeout, before
1256 sending again an USB request to the device.
1257
6705d81e 1258- Journaling Flash filesystem support:
b2482dff 1259 CONFIG_JFFS2_NAND
6705d81e
WD
1260 Define these for a default partition on a NAND device
1261
6d0f6bcf
JCPV
1262 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1263 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
6705d81e
WD
1264 Define these for a default partition on a NOR device
1265
c609719b 1266- Keyboard Support:
39f615ed
SG
1267 See Kconfig help for available keyboard drivers.
1268
1269 CONFIG_KEYBOARD
1270
1271 Define this to enable a custom keyboard support.
1272 This simply calls drv_keyboard_init() which must be
1273 defined in your board-specific files. This option is deprecated
1274 and is only used by novena. For new boards, use driver model
1275 instead.
c609719b
WD
1276
1277- Video support:
7d3053fb 1278 CONFIG_FSL_DIU_FB
04e5ae79 1279 Enable the Freescale DIU video driver. Reference boards for
7d3053fb
TT
1280 SOCs that have a DIU should define this macro to enable DIU
1281 support, and should also define these other macros:
1282
1283 CONFIG_SYS_DIU_ADDR
1284 CONFIG_VIDEO
7d3053fb
TT
1285 CONFIG_CFB_CONSOLE
1286 CONFIG_VIDEO_SW_CURSOR
1287 CONFIG_VGA_AS_SINGLE_DEVICE
1288 CONFIG_VIDEO_LOGO
1289 CONFIG_VIDEO_BMP_LOGO
1290
ba8e76bd
TT
1291 The DIU driver will look for the 'video-mode' environment
1292 variable, and if defined, enable the DIU as a console during
8eca9439 1293 boot. See the documentation file doc/README.video for a
ba8e76bd 1294 description of this variable.
7d3053fb 1295
c609719b
WD
1296- LCD Support: CONFIG_LCD
1297
1298 Define this to enable LCD support (for output to LCD
1299 display); also select one of the supported displays
1300 by defining one of these:
1301
39cf4804
SP
1302 CONFIG_ATMEL_LCD:
1303
1304 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1305
fd3103bb 1306 CONFIG_NEC_NL6448AC33:
c609719b 1307
fd3103bb 1308 NEC NL6448AC33-18. Active, color, single scan.
c609719b 1309
fd3103bb 1310 CONFIG_NEC_NL6448BC20
c609719b 1311
fd3103bb
WD
1312 NEC NL6448BC20-08. 6.5", 640x480.
1313 Active, color, single scan.
1314
1315 CONFIG_NEC_NL6448BC33_54
1316
1317 NEC NL6448BC33-54. 10.4", 640x480.
c609719b
WD
1318 Active, color, single scan.
1319
1320 CONFIG_SHARP_16x9
1321
1322 Sharp 320x240. Active, color, single scan.
1323 It isn't 16x9, and I am not sure what it is.
1324
1325 CONFIG_SHARP_LQ64D341
1326
1327 Sharp LQ64D341 display, 640x480.
1328 Active, color, single scan.
1329
1330 CONFIG_HLD1045
1331
1332 HLD1045 display, 640x480.
1333 Active, color, single scan.
1334
1335 CONFIG_OPTREX_BW
1336
1337 Optrex CBL50840-2 NF-FW 99 22 M5
1338 or
1339 Hitachi LMG6912RPFC-00T
1340 or
1341 Hitachi SP14Q002
1342
1343 320x240. Black & white.
1344
676d319e
SG
1345 CONFIG_LCD_ALIGNMENT
1346
b445bbb4 1347 Normally the LCD is page-aligned (typically 4KB). If this is
676d319e
SG
1348 defined then the LCD will be aligned to this value instead.
1349 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1350 here, since it is cheaper to change data cache settings on
1351 a per-section basis.
1352
1353
604c7d4a
HP
1354 CONFIG_LCD_ROTATION
1355
1356 Sometimes, for example if the display is mounted in portrait
1357 mode or even if it's mounted landscape but rotated by 180degree,
1358 we need to rotate our content of the display relative to the
1359 framebuffer, so that user can read the messages which are
1360 printed out.
1361 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1362 initialized with a given rotation from "vl_rot" out of
1363 "vidinfo_t" which is provided by the board specific code.
1364 The value for vl_rot is coded as following (matching to
1365 fbcon=rotate:<n> linux-kernel commandline):
1366 0 = no rotation respectively 0 degree
1367 1 = 90 degree rotation
1368 2 = 180 degree rotation
1369 3 = 270 degree rotation
1370
1371 If CONFIG_LCD_ROTATION is not defined, the console will be
1372 initialized with 0degree rotation.
1373
45d7f525
TWHT
1374 CONFIG_LCD_BMP_RLE8
1375
1376 Support drawing of RLE8-compressed bitmaps on the LCD.
1377
735987c5
TWHT
1378 CONFIG_I2C_EDID
1379
1380 Enables an 'i2c edid' command which can read EDID
1381 information over I2C from an attached LCD display.
1382
7152b1d0 1383- Splash Screen Support: CONFIG_SPLASH_SCREEN
d791b1dc 1384
8bde7f77
WD
1385 If this option is set, the environment is checked for
1386 a variable "splashimage". If found, the usual display
1387 of logo, copyright and system information on the LCD
e94d2cd9 1388 is suppressed and the BMP image at the address
8bde7f77
WD
1389 specified in "splashimage" is loaded instead. The
1390 console is redirected to the "nulldev", too. This
1391 allows for a "silent" boot where a splash screen is
1392 loaded very quickly after power-on.
d791b1dc 1393
c0880485
NK
1394 CONFIG_SPLASHIMAGE_GUARD
1395
1396 If this option is set, then U-Boot will prevent the environment
1397 variable "splashimage" from being set to a problematic address
ab5645f1 1398 (see doc/README.displaying-bmps).
c0880485
NK
1399 This option is useful for targets where, due to alignment
1400 restrictions, an improperly aligned BMP image will cause a data
1401 abort. If you think you will not have problems with unaligned
1402 accesses (for example because your toolchain prevents them)
1403 there is no need to set this option.
1404
1ca298ce
MW
1405 CONFIG_SPLASH_SCREEN_ALIGN
1406
1407 If this option is set the splash image can be freely positioned
1408 on the screen. Environment variable "splashpos" specifies the
1409 position as "x,y". If a positive number is given it is used as
1410 number of pixel from left/top. If a negative number is given it
1411 is used as number of pixel from right/bottom. You can also
1412 specify 'm' for centering the image.
1413
1414 Example:
1415 setenv splashpos m,m
1416 => image at center of screen
1417
1418 setenv splashpos 30,20
1419 => image at x = 30 and y = 20
1420
1421 setenv splashpos -10,m
1422 => vertically centered image
1423 at x = dspWidth - bmpWidth - 9
1424
98f4a3df
SR
1425- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1426
1427 If this option is set, additionally to standard BMP
1428 images, gzipped BMP images can be displayed via the
1429 splashscreen support or the bmp command.
1430
d5011762
AG
1431- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1432
1433 If this option is set, 8-bit RLE compressed BMP images
1434 can be displayed via the splashscreen support or the
1435 bmp command.
1436
c29fdfc1 1437- Compression support:
8ef70478
KC
1438 CONFIG_GZIP
1439
1440 Enabled by default to support gzip compressed images.
1441
c29fdfc1
WD
1442 CONFIG_BZIP2
1443
1444 If this option is set, support for bzip2 compressed
1445 images is included. If not, only uncompressed and gzip
1446 compressed images are supported.
1447
42d1f039 1448 NOTE: the bzip2 algorithm requires a lot of RAM, so
6d0f6bcf 1449 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
42d1f039 1450 be at least 4MB.
d791b1dc 1451
17ea1177
WD
1452- MII/PHY support:
1453 CONFIG_PHY_ADDR
1454
1455 The address of PHY on MII bus.
1456
1457 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1458
1459 The clock frequency of the MII bus
1460
17ea1177
WD
1461 CONFIG_PHY_RESET_DELAY
1462
1463 Some PHY like Intel LXT971A need extra delay after
1464 reset before any MII register access is possible.
1465 For such PHY, set this option to the usec delay
1466 required. (minimum 300usec for LXT971A)
1467
1468 CONFIG_PHY_CMD_DELAY (ppc4xx)
1469
1470 Some PHY like Intel LXT971A need extra delay after
1471 command issued before MII status register can be read
1472
c609719b
WD
1473- IP address:
1474 CONFIG_IPADDR
1475
1476 Define a default value for the IP address to use for
11ccc33f 1477 the default Ethernet interface, in case this is not
c609719b 1478 determined through e.g. bootp.
1ebcd654 1479 (Environment variable "ipaddr")
c609719b
WD
1480
1481- Server IP address:
1482 CONFIG_SERVERIP
1483
11ccc33f 1484 Defines a default value for the IP address of a TFTP
c609719b 1485 server to contact when using the "tftboot" command.
1ebcd654 1486 (Environment variable "serverip")
c609719b 1487
97cfe861
RG
1488 CONFIG_KEEP_SERVERADDR
1489
1490 Keeps the server's MAC address, in the env 'serveraddr'
1491 for passing to bootargs (like Linux's netconsole option)
1492
1ebcd654
WD
1493- Gateway IP address:
1494 CONFIG_GATEWAYIP
1495
1496 Defines a default value for the IP address of the
1497 default router where packets to other networks are
1498 sent to.
1499 (Environment variable "gatewayip")
1500
1501- Subnet mask:
1502 CONFIG_NETMASK
1503
1504 Defines a default value for the subnet mask (or
1505 routing prefix) which is used to determine if an IP
1506 address belongs to the local subnet or needs to be
1507 forwarded through a router.
1508 (Environment variable "netmask")
1509
53a5c424
DU
1510- Multicast TFTP Mode:
1511 CONFIG_MCAST_TFTP
1512
1513 Defines whether you want to support multicast TFTP as per
1514 rfc-2090; for example to work with atftp. Lets lots of targets
11ccc33f 1515 tftp down the same boot image concurrently. Note: the Ethernet
53a5c424
DU
1516 driver in use must provide a function: mcast() to join/leave a
1517 multicast group.
1518
c609719b
WD
1519- BOOTP Recovery Mode:
1520 CONFIG_BOOTP_RANDOM_DELAY
1521
1522 If you have many targets in a network that try to
1523 boot using BOOTP, you may want to avoid that all
1524 systems send out BOOTP requests at precisely the same
1525 moment (which would happen for instance at recovery
1526 from a power failure, when all systems will try to
1527 boot, thus flooding the BOOTP server. Defining
1528 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1529 inserted before sending out BOOTP requests. The
6c33c785 1530 following delays are inserted then:
c609719b
WD
1531
1532 1st BOOTP request: delay 0 ... 1 sec
1533 2nd BOOTP request: delay 0 ... 2 sec
1534 3rd BOOTP request: delay 0 ... 4 sec
1535 4th and following
1536 BOOTP requests: delay 0 ... 8 sec
1537
92ac8acc
TR
1538 CONFIG_BOOTP_ID_CACHE_SIZE
1539
1540 BOOTP packets are uniquely identified using a 32-bit ID. The
1541 server will copy the ID from client requests to responses and
1542 U-Boot will use this to determine if it is the destination of
1543 an incoming response. Some servers will check that addresses
1544 aren't in use before handing them out (usually using an ARP
1545 ping) and therefore take up to a few hundred milliseconds to
1546 respond. Network congestion may also influence the time it
1547 takes for a response to make it back to the client. If that
1548 time is too long, U-Boot will retransmit requests. In order
1549 to allow earlier responses to still be accepted after these
1550 retransmissions, U-Boot's BOOTP client keeps a small cache of
1551 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1552 cache. The default is to keep IDs for up to four outstanding
1553 requests. Increasing this will allow U-Boot to accept offers
1554 from a BOOTP client in networks with unusually high latency.
1555
fe389a82 1556- DHCP Advanced Options:
1fe80d79
JL
1557 You can fine tune the DHCP functionality by defining
1558 CONFIG_BOOTP_* symbols:
1559
1560 CONFIG_BOOTP_SUBNETMASK
1561 CONFIG_BOOTP_GATEWAY
1562 CONFIG_BOOTP_HOSTNAME
1563 CONFIG_BOOTP_NISDOMAIN
1564 CONFIG_BOOTP_BOOTPATH
1565 CONFIG_BOOTP_BOOTFILESIZE
1566 CONFIG_BOOTP_DNS
1567 CONFIG_BOOTP_DNS2
1568 CONFIG_BOOTP_SEND_HOSTNAME
1569 CONFIG_BOOTP_NTPSERVER
1570 CONFIG_BOOTP_TIMEOFFSET
1571 CONFIG_BOOTP_VENDOREX
2c00e099 1572 CONFIG_BOOTP_MAY_FAIL
fe389a82 1573
5d110f0a
WC
1574 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1575 environment variable, not the BOOTP server.
fe389a82 1576
2c00e099
JH
1577 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1578 after the configured retry count, the call will fail
1579 instead of starting over. This can be used to fail over
1580 to Link-local IP address configuration if the DHCP server
1581 is not available.
1582
fe389a82
SR
1583 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1584 serverip from a DHCP server, it is possible that more
1585 than one DNS serverip is offered to the client.
1586 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1587 serverip will be stored in the additional environment
1588 variable "dnsip2". The first DNS serverip is always
1589 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1fe80d79 1590 is defined.
fe389a82
SR
1591
1592 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1593 to do a dynamic update of a DNS server. To do this, they
1594 need the hostname of the DHCP requester.
5d110f0a 1595 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1fe80d79
JL
1596 of the "hostname" environment variable is passed as
1597 option 12 to the DHCP server.
fe389a82 1598
d9a2f416
AV
1599 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1600
1601 A 32bit value in microseconds for a delay between
1602 receiving a "DHCP Offer" and sending the "DHCP Request".
1603 This fixes a problem with certain DHCP servers that don't
1604 respond 100% of the time to a "DHCP request". E.g. On an
1605 AT91RM9200 processor running at 180MHz, this delay needed
1606 to be *at least* 15,000 usec before a Windows Server 2003
1607 DHCP server would reply 100% of the time. I recommend at
1608 least 50,000 usec to be safe. The alternative is to hope
1609 that one of the retries will be successful but note that
1610 the DHCP timeout and retry process takes a longer than
1611 this delay.
1612
d22c338e
JH
1613 - Link-local IP address negotiation:
1614 Negotiate with other link-local clients on the local network
1615 for an address that doesn't require explicit configuration.
1616 This is especially useful if a DHCP server cannot be guaranteed
1617 to exist in all environments that the device must operate.
1618
1619 See doc/README.link-local for more information.
1620
a3d991bd 1621 - CDP Options:
6e592385 1622 CONFIG_CDP_DEVICE_ID
a3d991bd
WD
1623
1624 The device id used in CDP trigger frames.
1625
1626 CONFIG_CDP_DEVICE_ID_PREFIX
1627
1628 A two character string which is prefixed to the MAC address
1629 of the device.
1630
1631 CONFIG_CDP_PORT_ID
1632
1633 A printf format string which contains the ascii name of
1634 the port. Normally is set to "eth%d" which sets
11ccc33f 1635 eth0 for the first Ethernet, eth1 for the second etc.
a3d991bd
WD
1636
1637 CONFIG_CDP_CAPABILITIES
1638
1639 A 32bit integer which indicates the device capabilities;
1640 0x00000010 for a normal host which does not forwards.
1641
1642 CONFIG_CDP_VERSION
1643
1644 An ascii string containing the version of the software.
1645
1646 CONFIG_CDP_PLATFORM
1647
1648 An ascii string containing the name of the platform.
1649
1650 CONFIG_CDP_TRIGGER
1651
1652 A 32bit integer sent on the trigger.
1653
1654 CONFIG_CDP_POWER_CONSUMPTION
1655
1656 A 16bit integer containing the power consumption of the
1657 device in .1 of milliwatts.
1658
1659 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1660
1661 A byte containing the id of the VLAN.
1662
79267edd 1663- Status LED: CONFIG_LED_STATUS
c609719b
WD
1664
1665 Several configurations allow to display the current
1666 status using a LED. For instance, the LED will blink
1667 fast while running U-Boot code, stop blinking as
1668 soon as a reply to a BOOTP request was received, and
1669 start blinking slow once the Linux kernel is running
1670 (supported by a status LED driver in the Linux
79267edd 1671 kernel). Defining CONFIG_LED_STATUS enables this
c609719b
WD
1672 feature in U-Boot.
1673
1df7bbba
IG
1674 Additional options:
1675
79267edd 1676 CONFIG_LED_STATUS_GPIO
1df7bbba
IG
1677 The status LED can be connected to a GPIO pin.
1678 In such cases, the gpio_led driver can be used as a
79267edd 1679 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
1df7bbba
IG
1680 to include the gpio_led driver in the U-Boot binary.
1681
9dfdcdfe
IG
1682 CONFIG_GPIO_LED_INVERTED_TABLE
1683 Some GPIO connected LEDs may have inverted polarity in which
1684 case the GPIO high value corresponds to LED off state and
1685 GPIO low value corresponds to LED on state.
1686 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1687 with a list of GPIO LEDs that have inverted polarity.
1688
3f4978c7
HS
1689- I2C Support: CONFIG_SYS_I2C
1690
1691 This enable the NEW i2c subsystem, and will allow you to use
1692 i2c commands at the u-boot command line (as long as you set
1693 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1694 based realtime clock chips or other i2c devices. See
1695 common/cmd_i2c.c for a description of the command line
1696 interface.
1697
1698 ported i2c driver to the new framework:
ea818dbb
HS
1699 - drivers/i2c/soft_i2c.c:
1700 - activate first bus with CONFIG_SYS_I2C_SOFT define
1701 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1702 for defining speed and slave address
1703 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1704 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1705 for defining speed and slave address
1706 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1707 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1708 for defining speed and slave address
1709 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1710 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1711 for defining speed and slave address
3f4978c7 1712
00f792e0
HS
1713 - drivers/i2c/fsl_i2c.c:
1714 - activate i2c driver with CONFIG_SYS_I2C_FSL
1715 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1716 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1717 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1718 bus.
93e14596 1719 - If your board supports a second fsl i2c bus, define
00f792e0
HS
1720 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1721 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1722 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1723 second bus.
1724
1f2ba722 1725 - drivers/i2c/tegra_i2c.c:
10cee516
NI
1726 - activate this driver with CONFIG_SYS_I2C_TEGRA
1727 - This driver adds 4 i2c buses with a fix speed from
1728 100000 and the slave addr 0!
1f2ba722 1729
880540de
DE
1730 - drivers/i2c/ppc4xx_i2c.c
1731 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1732 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1733 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1734
fac96408 1735 - drivers/i2c/i2c_mxc.c
1736 - activate this driver with CONFIG_SYS_I2C_MXC
03544c66
AA
1737 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
1738 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
1739 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
1740 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
fac96408 1741 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1742 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1743 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1744 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1745 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1746 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
03544c66
AA
1747 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
1748 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
b445bbb4 1749 If those defines are not set, default value is 100000
fac96408 1750 for speed, and 0 for slave.
1751
1086bfa9
NI
1752 - drivers/i2c/rcar_i2c.c:
1753 - activate this driver with CONFIG_SYS_I2C_RCAR
1754 - This driver adds 4 i2c buses
1755
1756 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
1757 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
1758 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
1759 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
1760 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
1761 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
1762 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
1763 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
1764 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
1765
2035d77d
NI
1766 - drivers/i2c/sh_i2c.c:
1767 - activate this driver with CONFIG_SYS_I2C_SH
1768 - This driver adds from 2 to 5 i2c buses
1769
1770 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
1771 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
1772 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
1773 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
1774 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
1775 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
1776 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
1777 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
1778 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
1779 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
b445bbb4 1780 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
2035d77d 1781
6789e84e
HS
1782 - drivers/i2c/omap24xx_i2c.c
1783 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
1784 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
1785 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
1786 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
1787 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
1788 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
1789 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
1790 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
1791 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
1792 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
1793 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
1794
0bdffe71
HS
1795 - drivers/i2c/zynq_i2c.c
1796 - activate this driver with CONFIG_SYS_I2C_ZYNQ
1797 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
1798 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
1799
e717fc6d
NKC
1800 - drivers/i2c/s3c24x0_i2c.c:
1801 - activate this driver with CONFIG_SYS_I2C_S3C24X0
1802 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1803 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1804 with a fix speed from 100000 and the slave addr 0!
1805
b46226bd
DE
1806 - drivers/i2c/ihs_i2c.c
1807 - activate this driver with CONFIG_SYS_I2C_IHS
1808 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1809 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1810 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1811 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1812 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1813 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1814 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1815 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1816 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1817 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1818 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1819 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
071be896
DE
1820 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1821 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1822 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1823 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1824 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1825 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1826 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1827 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1828 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
b46226bd 1829
3f4978c7
HS
1830 additional defines:
1831
1832 CONFIG_SYS_NUM_I2C_BUSES
945a18e6 1833 Hold the number of i2c buses you want to use.
3f4978c7
HS
1834
1835 CONFIG_SYS_I2C_DIRECT_BUS
1836 define this, if you don't use i2c muxes on your hardware.
1837 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1838 omit this define.
1839
1840 CONFIG_SYS_I2C_MAX_HOPS
1841 define how many muxes are maximal consecutively connected
1842 on one i2c bus. If you not use i2c muxes, omit this
1843 define.
1844
1845 CONFIG_SYS_I2C_BUSES
b445bbb4 1846 hold a list of buses you want to use, only used if
3f4978c7
HS
1847 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1848 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1849 CONFIG_SYS_NUM_I2C_BUSES = 9:
1850
1851 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1852 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1853 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1854 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1855 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1856 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1857 {1, {I2C_NULL_HOP}}, \
1858 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1859 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1860 }
1861
1862 which defines
1863 bus 0 on adapter 0 without a mux
ea818dbb
HS
1864 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1865 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1866 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1867 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1868 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
3f4978c7 1869 bus 6 on adapter 1 without a mux
ea818dbb
HS
1870 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1871 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
3f4978c7
HS
1872
1873 If you do not have i2c muxes on your board, omit this define.
1874
ce3b5d69 1875- Legacy I2C Support:
ea818dbb 1876 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
b37c7e5e
WD
1877 then the following macros need to be defined (examples are
1878 from include/configs/lwmon.h):
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WD
1879
1880 I2C_INIT
1881
b37c7e5e 1882 (Optional). Any commands necessary to enable the I2C
43d9616c 1883 controller or configure ports.
c609719b 1884
ba56f625 1885 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
b37c7e5e 1886
c609719b
WD
1887 I2C_ACTIVE
1888
1889 The code necessary to make the I2C data line active
1890 (driven). If the data line is open collector, this
1891 define can be null.
1892
b37c7e5e
WD
1893 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1894
c609719b
WD
1895 I2C_TRISTATE
1896
1897 The code necessary to make the I2C data line tri-stated
1898 (inactive). If the data line is open collector, this
1899 define can be null.
1900
b37c7e5e
WD
1901 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1902
c609719b
WD
1903 I2C_READ
1904
472d5460
YS
1905 Code that returns true if the I2C data line is high,
1906 false if it is low.
c609719b 1907
b37c7e5e
WD
1908 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1909
c609719b
WD
1910 I2C_SDA(bit)
1911
472d5460
YS
1912 If <bit> is true, sets the I2C data line high. If it
1913 is false, it clears it (low).
c609719b 1914
b37c7e5e 1915 eg: #define I2C_SDA(bit) \
2535d602 1916 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
ba56f625 1917 else immr->im_cpm.cp_pbdat &= ~PB_SDA
b37c7e5e 1918
c609719b
WD
1919 I2C_SCL(bit)
1920
472d5460
YS
1921 If <bit> is true, sets the I2C clock line high. If it
1922 is false, it clears it (low).
c609719b 1923
b37c7e5e 1924 eg: #define I2C_SCL(bit) \
2535d602 1925 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
ba56f625 1926 else immr->im_cpm.cp_pbdat &= ~PB_SCL
b37c7e5e 1927
c609719b
WD
1928 I2C_DELAY
1929
1930 This delay is invoked four times per clock cycle so this
1931 controls the rate of data transfer. The data rate thus
b37c7e5e 1932 is 1 / (I2C_DELAY * 4). Often defined to be something
945af8d7
WD
1933 like:
1934
b37c7e5e 1935 #define I2C_DELAY udelay(2)
c609719b 1936
793b5726
MF
1937 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1938
1939 If your arch supports the generic GPIO framework (asm/gpio.h),
1940 then you may alternatively define the two GPIOs that are to be
1941 used as SCL / SDA. Any of the previous I2C_xxx macros will
1942 have GPIO-based defaults assigned to them as appropriate.
1943
1944 You should define these to the GPIO value as given directly to
1945 the generic GPIO functions.
1946
6d0f6bcf 1947 CONFIG_SYS_I2C_INIT_BOARD
47cd00fa 1948
8bde7f77
WD
1949 When a board is reset during an i2c bus transfer
1950 chips might think that the current transfer is still
1951 in progress. On some boards it is possible to access
1952 the i2c SCLK line directly, either by using the
1953 processor pin as a GPIO or by having a second pin
1954 connected to the bus. If this option is defined a
1955 custom i2c_init_board() routine in boards/xxx/board.c
1956 is run early in the boot sequence.
47cd00fa 1957
bb99ad6d
BW
1958 CONFIG_I2C_MULTI_BUS
1959
1960 This option allows the use of multiple I2C buses, each of which
c0f40859
WD
1961 must have a controller. At any point in time, only one bus is
1962 active. To switch to a different bus, use the 'i2c dev' command.
bb99ad6d
BW
1963 Note that bus numbering is zero-based.
1964
6d0f6bcf 1965 CONFIG_SYS_I2C_NOPROBES
bb99ad6d
BW
1966
1967 This option specifies a list of I2C devices that will be skipped
c0f40859 1968 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
0f89c54b
PT
1969 is set, specify a list of bus-device pairs. Otherwise, specify
1970 a 1D array of device addresses
bb99ad6d
BW
1971
1972 e.g.
1973 #undef CONFIG_I2C_MULTI_BUS
c0f40859 1974 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
bb99ad6d
BW
1975
1976 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1977
c0f40859 1978 #define CONFIG_I2C_MULTI_BUS
945a18e6 1979 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
bb99ad6d
BW
1980
1981 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1982
6d0f6bcf 1983 CONFIG_SYS_SPD_BUS_NUM
be5e6181
TT
1984
1985 If defined, then this indicates the I2C bus number for DDR SPD.
1986 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1987
6d0f6bcf 1988 CONFIG_SYS_RTC_BUS_NUM
0dc018ec
SR
1989
1990 If defined, then this indicates the I2C bus number for the RTC.
1991 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1992
2ac6985a
AD
1993 CONFIG_SOFT_I2C_READ_REPEATED_START
1994
1995 defining this will force the i2c_read() function in
1996 the soft_i2c driver to perform an I2C repeated start
1997 between writing the address pointer and reading the
1998 data. If this define is omitted the default behaviour
1999 of doing a stop-start sequence will be used. Most I2C
2000 devices can use either method, but some require one or
2001 the other.
be5e6181 2002
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WD
2003- SPI Support: CONFIG_SPI
2004
2005 Enables SPI driver (so far only tested with
2006 SPI EEPROM, also an instance works with Crystal A/D and
2007 D/As on the SACSng board)
2008
6639562e
YS
2009 CONFIG_SH_SPI
2010
2011 Enables the driver for SPI controller on SuperH. Currently
2012 only SH7757 is supported.
2013
c609719b
WD
2014 CONFIG_SOFT_SPI
2015
43d9616c
WD
2016 Enables a software (bit-bang) SPI driver rather than
2017 using hardware support. This is a general purpose
2018 driver that only requires three general I/O port pins
2019 (two outputs, one input) to function. If this is
2020 defined, the board configuration must define several
2021 SPI configuration items (port pins to use, etc). For
2022 an example, see include/configs/sacsng.h.
c609719b 2023
04a9e118
BW
2024 CONFIG_HARD_SPI
2025
2026 Enables a hardware SPI driver for general-purpose reads
2027 and writes. As with CONFIG_SOFT_SPI, the board configuration
2028 must define a list of chip-select function pointers.
c0f40859 2029 Currently supported on some MPC8xxx processors. For an
04a9e118
BW
2030 example, see include/configs/mpc8349emds.h.
2031
38254f45
GL
2032 CONFIG_MXC_SPI
2033
2034 Enables the driver for the SPI controllers on i.MX and MXC
2e3cd1cd 2035 SoCs. Currently i.MX31/35/51 are supported.
38254f45 2036
f659b573
HS
2037 CONFIG_SYS_SPI_MXC_WAIT
2038 Timeout for waiting until spi transfer completed.
2039 default: (CONFIG_SYS_HZ/100) /* 10 ms */
2040
0133502e 2041- FPGA Support: CONFIG_FPGA
c609719b 2042
0133502e
MF
2043 Enables FPGA subsystem.
2044
2045 CONFIG_FPGA_<vendor>
2046
2047 Enables support for specific chip vendors.
2048 (ALTERA, XILINX)
c609719b 2049
0133502e 2050 CONFIG_FPGA_<family>
c609719b 2051
0133502e
MF
2052 Enables support for FPGA family.
2053 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2054
2055 CONFIG_FPGA_COUNT
2056
2057 Specify the number of FPGA devices to support.
c609719b 2058
6d0f6bcf 2059 CONFIG_SYS_FPGA_PROG_FEEDBACK
c609719b 2060
8bde7f77 2061 Enable printing of hash marks during FPGA configuration.
c609719b 2062
6d0f6bcf 2063 CONFIG_SYS_FPGA_CHECK_BUSY
c609719b 2064
43d9616c
WD
2065 Enable checks on FPGA configuration interface busy
2066 status by the configuration function. This option
2067 will require a board or device specific function to
2068 be written.
c609719b
WD
2069
2070 CONFIG_FPGA_DELAY
2071
2072 If defined, a function that provides delays in the FPGA
2073 configuration driver.
2074
6d0f6bcf 2075 CONFIG_SYS_FPGA_CHECK_CTRLC
c609719b
WD
2076 Allow Control-C to interrupt FPGA configuration
2077
6d0f6bcf 2078 CONFIG_SYS_FPGA_CHECK_ERROR
c609719b 2079
43d9616c
WD
2080 Check for configuration errors during FPGA bitfile
2081 loading. For example, abort during Virtex II
2082 configuration if the INIT_B line goes low (which
2083 indicated a CRC error).
c609719b 2084
6d0f6bcf 2085 CONFIG_SYS_FPGA_WAIT_INIT
c609719b 2086
b445bbb4
JM
2087 Maximum time to wait for the INIT_B line to de-assert
2088 after PROB_B has been de-asserted during a Virtex II
43d9616c 2089 FPGA configuration sequence. The default time is 500
11ccc33f 2090 ms.
c609719b 2091
6d0f6bcf 2092 CONFIG_SYS_FPGA_WAIT_BUSY
c609719b 2093
b445bbb4 2094 Maximum time to wait for BUSY to de-assert during
11ccc33f 2095 Virtex II FPGA configuration. The default is 5 ms.
c609719b 2096
6d0f6bcf 2097 CONFIG_SYS_FPGA_WAIT_CONFIG
c609719b 2098
43d9616c 2099 Time to wait after FPGA configuration. The default is
11ccc33f 2100 200 ms.
c609719b
WD
2101
2102- Configuration Management:
b2b8a696
SR
2103 CONFIG_BUILD_TARGET
2104
2105 Some SoCs need special image types (e.g. U-Boot binary
2106 with a special header) as build targets. By defining
2107 CONFIG_BUILD_TARGET in the SoC / board header, this
2108 special image will be automatically built upon calling
6de80f21 2109 make / buildman.
b2b8a696 2110
c609719b
WD
2111 CONFIG_IDENT_STRING
2112
43d9616c
WD
2113 If defined, this string will be added to the U-Boot
2114 version information (U_BOOT_VERSION)
c609719b
WD
2115
2116- Vendor Parameter Protection:
2117
43d9616c
WD
2118 U-Boot considers the values of the environment
2119 variables "serial#" (Board Serial Number) and
7152b1d0 2120 "ethaddr" (Ethernet Address) to be parameters that
43d9616c
WD
2121 are set once by the board vendor / manufacturer, and
2122 protects these variables from casual modification by
2123 the user. Once set, these variables are read-only,
2124 and write or delete attempts are rejected. You can
11ccc33f 2125 change this behaviour:
c609719b
WD
2126
2127 If CONFIG_ENV_OVERWRITE is #defined in your config
2128 file, the write protection for vendor parameters is
47cd00fa 2129 completely disabled. Anybody can change or delete
c609719b
WD
2130 these parameters.
2131
92ac5208
JH
2132 Alternatively, if you define _both_ an ethaddr in the
2133 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
11ccc33f 2134 Ethernet address is installed in the environment,
c609719b
WD
2135 which can be changed exactly ONCE by the user. [The
2136 serial# is unaffected by this, i. e. it remains
2137 read-only.]
2138
2598090b
JH
2139 The same can be accomplished in a more flexible way
2140 for any variable by configuring the type of access
2141 to allow for those variables in the ".flags" variable
2142 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2143
c609719b
WD
2144- Protected RAM:
2145 CONFIG_PRAM
2146
2147 Define this variable to enable the reservation of
2148 "protected RAM", i. e. RAM which is not overwritten
2149 by U-Boot. Define CONFIG_PRAM to hold the number of
2150 kB you want to reserve for pRAM. You can overwrite
2151 this default value by defining an environment
2152 variable "pram" to the number of kB you want to
2153 reserve. Note that the board info structure will
2154 still show the full amount of RAM. If pRAM is
2155 reserved, a new environment variable "mem" will
2156 automatically be defined to hold the amount of
2157 remaining RAM in a form that can be passed as boot
2158 argument to Linux, for instance like that:
2159
fe126d8b 2160 setenv bootargs ... mem=\${mem}
c609719b
WD
2161 saveenv
2162
2163 This way you can tell Linux not to use this memory,
2164 either, which results in a memory region that will
2165 not be affected by reboots.
2166
2167 *WARNING* If your board configuration uses automatic
2168 detection of the RAM size, you must make sure that
2169 this memory test is non-destructive. So far, the
2170 following board configurations are known to be
2171 "pRAM-clean":
2172
5b8e76c3 2173 IVMS8, IVML24, SPD8xx,
1b0757ec 2174 HERMES, IP860, RPXlite, LWMON,
2eb48ff7 2175 FLAGADM
c609719b 2176
40fef049
GB
2177- Access to physical memory region (> 4GB)
2178 Some basic support is provided for operations on memory not
2179 normally accessible to U-Boot - e.g. some architectures
2180 support access to more than 4GB of memory on 32-bit
2181 machines using physical address extension or similar.
2182 Define CONFIG_PHYSMEM to access this basic support, which
2183 currently only supports clearing the memory.
2184
c609719b
WD
2185- Error Recovery:
2186 CONFIG_PANIC_HANG
2187
2188 Define this variable to stop the system in case of a
2189 fatal error, so that you have to reset it manually.
2190 This is probably NOT a good idea for an embedded
11ccc33f 2191 system where you want the system to reboot
c609719b
WD
2192 automatically as fast as possible, but it may be
2193 useful during development since you can try to debug
2194 the conditions that lead to the situation.
2195
2196 CONFIG_NET_RETRY_COUNT
2197
43d9616c
WD
2198 This variable defines the number of retries for
2199 network operations like ARP, RARP, TFTP, or BOOTP
2200 before giving up the operation. If not defined, a
2201 default value of 5 is used.
c609719b 2202
40cb90ee
GL
2203 CONFIG_ARP_TIMEOUT
2204
2205 Timeout waiting for an ARP reply in milliseconds.
2206
48a3e999
TK
2207 CONFIG_NFS_TIMEOUT
2208
2209 Timeout in milliseconds used in NFS protocol.
2210 If you encounter "ERROR: Cannot umount" in nfs command,
2211 try longer timeout such as
2212 #define CONFIG_NFS_TIMEOUT 10000UL
2213
c609719b 2214- Command Interpreter:
8078f1a5 2215 CONFIG_AUTO_COMPLETE
04a85b3b
WD
2216
2217 Enable auto completion of commands using TAB.
2218
6d0f6bcf 2219 CONFIG_SYS_PROMPT_HUSH_PS2
c609719b
WD
2220
2221 This defines the secondary prompt string, which is
2222 printed when the command interpreter needs more input
2223 to complete a command. Usually "> ".
2224
2225 Note:
2226
8bde7f77
WD
2227 In the current implementation, the local variables
2228 space and global environment variables space are
2229 separated. Local variables are those you define by
2230 simply typing `name=value'. To access a local
2231 variable later on, you have write `$name' or
2232 `${name}'; to execute the contents of a variable
2233 directly type `$name' at the command prompt.
c609719b 2234
43d9616c
WD
2235 Global environment variables are those you use
2236 setenv/printenv to work with. To run a command stored
2237 in such a variable, you need to use the run command,
2238 and you must not use the '$' sign to access them.
c609719b
WD
2239
2240 To store commands and special characters in a
2241 variable, please use double quotation marks
2242 surrounding the whole text of the variable, instead
2243 of the backslashes before semicolons and special
2244 symbols.
2245
b445bbb4 2246- Command Line Editing and History:
aa0c71ac
WD
2247 CONFIG_CMDLINE_EDITING
2248
11ccc33f 2249 Enable editing and History functions for interactive
b445bbb4 2250 command line input operations
aa0c71ac 2251
f3b267b3
MV
2252- Command Line PS1/PS2 support:
2253 CONFIG_CMDLINE_PS_SUPPORT
2254
2255 Enable support for changing the command prompt string
2256 at run-time. Only static string is supported so far.
2257 The string is obtained from environment variables PS1
2258 and PS2.
2259
a8c7c708 2260- Default Environment:
c609719b
WD
2261 CONFIG_EXTRA_ENV_SETTINGS
2262
43d9616c
WD
2263 Define this to contain any number of null terminated
2264 strings (variable = value pairs) that will be part of
7152b1d0 2265 the default environment compiled into the boot image.
2262cfee 2266
43d9616c
WD
2267 For example, place something like this in your
2268 board's config file:
c609719b
WD
2269
2270 #define CONFIG_EXTRA_ENV_SETTINGS \
2271 "myvar1=value1\0" \
2272 "myvar2=value2\0"
2273
43d9616c
WD
2274 Warning: This method is based on knowledge about the
2275 internal format how the environment is stored by the
2276 U-Boot code. This is NOT an official, exported
2277 interface! Although it is unlikely that this format
7152b1d0 2278 will change soon, there is no guarantee either.
c609719b
WD
2279 You better know what you are doing here.
2280
43d9616c
WD
2281 Note: overly (ab)use of the default environment is
2282 discouraged. Make sure to check other ways to preset
74de7aef 2283 the environment like the "source" command or the
43d9616c 2284 boot command first.
c609719b 2285
5e724ca2
SW
2286 CONFIG_ENV_VARS_UBOOT_CONFIG
2287
2288 Define this in order to add variables describing the
2289 U-Boot build configuration to the default environment.
2290 These will be named arch, cpu, board, vendor, and soc.
2291
2292 Enabling this option will cause the following to be defined:
2293
2294 - CONFIG_SYS_ARCH
2295 - CONFIG_SYS_CPU
2296 - CONFIG_SYS_BOARD
2297 - CONFIG_SYS_VENDOR
2298 - CONFIG_SYS_SOC
2299
7e27f89f
TR
2300 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2301
2302 Define this in order to add variables describing certain
2303 run-time determined information about the hardware to the
2304 environment. These will be named board_name, board_rev.
2305
06fd8538
SG
2306 CONFIG_DELAY_ENVIRONMENT
2307
2308 Normally the environment is loaded when the board is
b445bbb4 2309 initialised so that it is available to U-Boot. This inhibits
06fd8538
SG
2310 that so that the environment is not available until
2311 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2312 this is instead controlled by the value of
2313 /config/load-environment.
2314
a8c7c708 2315- DataFlash Support:
2abbe075
WD
2316 CONFIG_HAS_DATAFLASH
2317
8bde7f77
WD
2318 Defining this option enables DataFlash features and
2319 allows to read/write in Dataflash via the standard
2320 commands cp, md...
2abbe075 2321
f61ec45e 2322- Serial Flash support
00fd59dd 2323 Usage requires an initial 'sf probe' to define the serial
f61ec45e
EN
2324 flash parameters, followed by read/write/erase/update
2325 commands.
2326
2327 The following defaults may be provided by the platform
2328 to handle the common case when only a single serial
2329 flash is present on the system.
2330
2331 CONFIG_SF_DEFAULT_BUS Bus identifier
2332 CONFIG_SF_DEFAULT_CS Chip-select
2333 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2334 CONFIG_SF_DEFAULT_SPEED in Hz
2335
3f85ce27
WD
2336 CONFIG_SYSTEMACE
2337
2338 Adding this option adds support for Xilinx SystemACE
2339 chips attached via some sort of local bus. The address
11ccc33f 2340 of the chip must also be defined in the
6d0f6bcf 2341 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
3f85ce27
WD
2342
2343 #define CONFIG_SYSTEMACE
6d0f6bcf 2344 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
3f85ce27
WD
2345
2346 When SystemACE support is added, the "ace" device type
2347 becomes available to the fat commands, i.e. fatls.
2348
ecb0ccd9
WD
2349- TFTP Fixed UDP Port:
2350 CONFIG_TFTP_PORT
2351
28cb9375 2352 If this is defined, the environment variable tftpsrcp
ecb0ccd9 2353 is used to supply the TFTP UDP source port value.
28cb9375 2354 If tftpsrcp isn't defined, the normal pseudo-random port
ecb0ccd9
WD
2355 number generator is used.
2356
28cb9375
WD
2357 Also, the environment variable tftpdstp is used to supply
2358 the TFTP UDP destination port value. If tftpdstp isn't
2359 defined, the normal port 69 is used.
2360
2361 The purpose for tftpsrcp is to allow a TFTP server to
ecb0ccd9
WD
2362 blindly start the TFTP transfer using the pre-configured
2363 target IP address and UDP port. This has the effect of
2364 "punching through" the (Windows XP) firewall, allowing
2365 the remainder of the TFTP transfer to proceed normally.
2366 A better solution is to properly configure the firewall,
2367 but sometimes that is not allowed.
2368
9e50c406
HS
2369- bootcount support:
2370 CONFIG_BOOTCOUNT_LIMIT
2371
2372 This enables the bootcounter support, see:
2373 http://www.denx.de/wiki/DULG/UBootBootCountLimit
2374
2375 CONFIG_AT91SAM9XE
2376 enable special bootcounter support on at91sam9xe based boards.
9e50c406
HS
2377 CONFIG_SOC_DA8XX
2378 enable special bootcounter support on da850 based boards.
2379 CONFIG_BOOTCOUNT_RAM
2380 enable support for the bootcounter in RAM
2381 CONFIG_BOOTCOUNT_I2C
2382 enable support for the bootcounter on an i2c (like RTC) device.
2383 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
2384 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
2385 the bootcounter.
2386 CONFIG_BOOTCOUNT_ALEN = address len
19c402af 2387
a8c7c708 2388- Show boot progress:
c609719b
WD
2389 CONFIG_SHOW_BOOT_PROGRESS
2390
43d9616c
WD
2391 Defining this option allows to add some board-
2392 specific code (calling a user-provided function
2393 "show_boot_progress(int)") that enables you to show
2394 the system's boot progress on some display (for
2395 example, some LED's) on your board. At the moment,
2396 the following checkpoints are implemented:
c609719b 2397
94fd1316 2398
1372cce2
MB
2399Legacy uImage format:
2400
c609719b
WD
2401 Arg Where When
2402 1 common/cmd_bootm.c before attempting to boot an image
ba56f625 2403 -1 common/cmd_bootm.c Image header has bad magic number
c609719b 2404 2 common/cmd_bootm.c Image header has correct magic number
ba56f625 2405 -2 common/cmd_bootm.c Image header has bad checksum
c609719b 2406 3 common/cmd_bootm.c Image header has correct checksum
ba56f625 2407 -3 common/cmd_bootm.c Image data has bad checksum
c609719b
WD
2408 4 common/cmd_bootm.c Image data has correct checksum
2409 -4 common/cmd_bootm.c Image is for unsupported architecture
2410 5 common/cmd_bootm.c Architecture check OK
1372cce2 2411 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
c609719b
WD
2412 6 common/cmd_bootm.c Image Type check OK
2413 -6 common/cmd_bootm.c gunzip uncompression error
2414 -7 common/cmd_bootm.c Unimplemented compression type
2415 7 common/cmd_bootm.c Uncompression OK
1372cce2 2416 8 common/cmd_bootm.c No uncompress/copy overwrite error
c609719b 2417 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1372cce2
MB
2418
2419 9 common/image.c Start initial ramdisk verification
2420 -10 common/image.c Ramdisk header has bad magic number
2421 -11 common/image.c Ramdisk header has bad checksum
2422 10 common/image.c Ramdisk header is OK
2423 -12 common/image.c Ramdisk data has bad checksum
2424 11 common/image.c Ramdisk data has correct checksum
2425 12 common/image.c Ramdisk verification complete, start loading
11ccc33f 2426 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
1372cce2
MB
2427 13 common/image.c Start multifile image verification
2428 14 common/image.c No initial ramdisk, no multifile, continue.
2429
c0f40859 2430 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
c609719b 2431
a47a12be 2432 -30 arch/powerpc/lib/board.c Fatal error, hang the system
11dadd54
WD
2433 -31 post/post.c POST test failed, detected by post_output_backlog()
2434 -32 post/post.c POST test failed, detected by post_run_single()
63e73c9a 2435
566a494f
HS
2436 34 common/cmd_doc.c before loading a Image from a DOC device
2437 -35 common/cmd_doc.c Bad usage of "doc" command
2438 35 common/cmd_doc.c correct usage of "doc" command
2439 -36 common/cmd_doc.c No boot device
2440 36 common/cmd_doc.c correct boot device
2441 -37 common/cmd_doc.c Unknown Chip ID on boot device
2442 37 common/cmd_doc.c correct chip ID found, device available
2443 -38 common/cmd_doc.c Read Error on boot device
2444 38 common/cmd_doc.c reading Image header from DOC device OK
2445 -39 common/cmd_doc.c Image header has bad magic number
2446 39 common/cmd_doc.c Image header has correct magic number
2447 -40 common/cmd_doc.c Error reading Image from DOC device
2448 40 common/cmd_doc.c Image header has correct magic number
2449 41 common/cmd_ide.c before loading a Image from a IDE device
2450 -42 common/cmd_ide.c Bad usage of "ide" command
2451 42 common/cmd_ide.c correct usage of "ide" command
2452 -43 common/cmd_ide.c No boot device
2453 43 common/cmd_ide.c boot device found
2454 -44 common/cmd_ide.c Device not available
2455 44 common/cmd_ide.c Device available
2456 -45 common/cmd_ide.c wrong partition selected
2457 45 common/cmd_ide.c partition selected
2458 -46 common/cmd_ide.c Unknown partition table
2459 46 common/cmd_ide.c valid partition table found
2460 -47 common/cmd_ide.c Invalid partition type
2461 47 common/cmd_ide.c correct partition type
2462 -48 common/cmd_ide.c Error reading Image Header on boot device
2463 48 common/cmd_ide.c reading Image Header from IDE device OK
2464 -49 common/cmd_ide.c Image header has bad magic number
2465 49 common/cmd_ide.c Image header has correct magic number
2466 -50 common/cmd_ide.c Image header has bad checksum
2467 50 common/cmd_ide.c Image header has correct checksum
2468 -51 common/cmd_ide.c Error reading Image from IDE device
2469 51 common/cmd_ide.c reading Image from IDE device OK
2470 52 common/cmd_nand.c before loading a Image from a NAND device
2471 -53 common/cmd_nand.c Bad usage of "nand" command
2472 53 common/cmd_nand.c correct usage of "nand" command
2473 -54 common/cmd_nand.c No boot device
2474 54 common/cmd_nand.c boot device found
2475 -55 common/cmd_nand.c Unknown Chip ID on boot device
2476 55 common/cmd_nand.c correct chip ID found, device available
2477 -56 common/cmd_nand.c Error reading Image Header on boot device
2478 56 common/cmd_nand.c reading Image Header from NAND device OK
2479 -57 common/cmd_nand.c Image header has bad magic number
2480 57 common/cmd_nand.c Image header has correct magic number
2481 -58 common/cmd_nand.c Error reading Image from NAND device
2482 58 common/cmd_nand.c reading Image from NAND device OK
2483
2484 -60 common/env_common.c Environment has a bad CRC, using default
2485
11ccc33f 2486 64 net/eth.c starting with Ethernet configuration.
566a494f
HS
2487 -64 net/eth.c no Ethernet found.
2488 65 net/eth.c Ethernet found.
2489
2490 -80 common/cmd_net.c usage wrong
bc0571fc
JH
2491 80 common/cmd_net.c before calling net_loop()
2492 -81 common/cmd_net.c some error in net_loop() occurred
2493 81 common/cmd_net.c net_loop() back without error
566a494f
HS
2494 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2495 82 common/cmd_net.c trying automatic boot
74de7aef
WD
2496 83 common/cmd_net.c running "source" command
2497 -83 common/cmd_net.c some error in automatic boot or "source" command
566a494f 2498 84 common/cmd_net.c end without errors
c609719b 2499
1372cce2
MB
2500FIT uImage format:
2501
2502 Arg Where When
2503 100 common/cmd_bootm.c Kernel FIT Image has correct format
2504 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2505 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2506 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2507 102 common/cmd_bootm.c Kernel unit name specified
2508 -103 common/cmd_bootm.c Can't get kernel subimage node offset
f773bea8 2509 103 common/cmd_bootm.c Found configuration node
1372cce2
MB
2510 104 common/cmd_bootm.c Got kernel subimage node offset
2511 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2512 105 common/cmd_bootm.c Kernel subimage hash verification OK
2513 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2514 106 common/cmd_bootm.c Architecture check OK
11ccc33f
MZ
2515 -106 common/cmd_bootm.c Kernel subimage has wrong type
2516 107 common/cmd_bootm.c Kernel subimage type OK
1372cce2
MB
2517 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2518 108 common/cmd_bootm.c Got kernel subimage data/size
2519 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2520 -109 common/cmd_bootm.c Can't get kernel subimage type
2521 -110 common/cmd_bootm.c Can't get kernel subimage comp
2522 -111 common/cmd_bootm.c Can't get kernel subimage os
2523 -112 common/cmd_bootm.c Can't get kernel subimage load address
2524 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2525
2526 120 common/image.c Start initial ramdisk verification
2527 -120 common/image.c Ramdisk FIT image has incorrect format
2528 121 common/image.c Ramdisk FIT image has correct format
11ccc33f 2529 122 common/image.c No ramdisk subimage unit name, using configuration
1372cce2
MB
2530 -122 common/image.c Can't get configuration for ramdisk subimage
2531 123 common/image.c Ramdisk unit name specified
2532 -124 common/image.c Can't get ramdisk subimage node offset
2533 125 common/image.c Got ramdisk subimage node offset
2534 -125 common/image.c Ramdisk subimage hash verification failed
2535 126 common/image.c Ramdisk subimage hash verification OK
2536 -126 common/image.c Ramdisk subimage for unsupported architecture
2537 127 common/image.c Architecture check OK
2538 -127 common/image.c Can't get ramdisk subimage data/size
2539 128 common/image.c Got ramdisk subimage data/size
2540 129 common/image.c Can't get ramdisk load address
2541 -129 common/image.c Got ramdisk load address
2542
11ccc33f 2543 -130 common/cmd_doc.c Incorrect FIT image format
1372cce2
MB
2544 131 common/cmd_doc.c FIT image format OK
2545
11ccc33f 2546 -140 common/cmd_ide.c Incorrect FIT image format
1372cce2
MB
2547 141 common/cmd_ide.c FIT image format OK
2548
11ccc33f 2549 -150 common/cmd_nand.c Incorrect FIT image format
1372cce2
MB
2550 151 common/cmd_nand.c FIT image format OK
2551
21d29f7f
HS
2552- legacy image format:
2553 CONFIG_IMAGE_FORMAT_LEGACY
2554 enables the legacy image format support in U-Boot.
2555
2556 Default:
2557 enabled if CONFIG_FIT_SIGNATURE is not defined.
2558
2559 CONFIG_DISABLE_IMAGE_LEGACY
2560 disable the legacy image format
2561
2562 This define is introduced, as the legacy image format is
2563 enabled per default for backward compatibility.
2564
4cf2609b
WD
2565- Standalone program support:
2566 CONFIG_STANDALONE_LOAD_ADDR
2567
6feff899
WD
2568 This option defines a board specific value for the
2569 address where standalone program gets loaded, thus
2570 overwriting the architecture dependent default
4cf2609b
WD
2571 settings.
2572
2573- Frame Buffer Address:
2574 CONFIG_FB_ADDR
2575
2576 Define CONFIG_FB_ADDR if you want to use specific
44a53b57
WD
2577 address for frame buffer. This is typically the case
2578 when using a graphics controller has separate video
2579 memory. U-Boot will then place the frame buffer at
2580 the given address instead of dynamically reserving it
2581 in system RAM by calling lcd_setmem(), which grabs
2582 the memory for the frame buffer depending on the
2583 configured panel size.
4cf2609b
WD
2584
2585 Please see board_init_f function.
2586
cccfc2ab
DZ
2587- Automatic software updates via TFTP server
2588 CONFIG_UPDATE_TFTP
2589 CONFIG_UPDATE_TFTP_CNT_MAX
2590 CONFIG_UPDATE_TFTP_MSEC_MAX
2591
2592 These options enable and control the auto-update feature;
2593 for a more detailed description refer to doc/README.update.
2594
2595- MTD Support (mtdparts command, UBI support)
2596 CONFIG_MTD_DEVICE
2597
2598 Adds the MTD device infrastructure from the Linux kernel.
2599 Needed for mtdparts command support.
2600
2601 CONFIG_MTD_PARTITIONS
2602
2603 Adds the MTD partitioning infrastructure from the Linux
2604 kernel. Needed for UBI support.
2605
70c219cd 2606- UBI support
147162da
JH
2607 CONFIG_UBI_SILENCE_MSG
2608
2609 Make the verbose messages from UBI stop printing. This leaves
2610 warnings and errors enabled.
2611
ff94bc40
HS
2612
2613 CONFIG_MTD_UBI_WL_THRESHOLD
2614 This parameter defines the maximum difference between the highest
2615 erase counter value and the lowest erase counter value of eraseblocks
2616 of UBI devices. When this threshold is exceeded, UBI starts performing
2617 wear leveling by means of moving data from eraseblock with low erase
2618 counter to eraseblocks with high erase counter.
2619
2620 The default value should be OK for SLC NAND flashes, NOR flashes and
2621 other flashes which have eraseblock life-cycle 100000 or more.
2622 However, in case of MLC NAND flashes which typically have eraseblock
2623 life-cycle less than 10000, the threshold should be lessened (e.g.,
2624 to 128 or 256, although it does not have to be power of 2).
2625
2626 default: 4096
c654b517 2627
ff94bc40
HS
2628 CONFIG_MTD_UBI_BEB_LIMIT
2629 This option specifies the maximum bad physical eraseblocks UBI
2630 expects on the MTD device (per 1024 eraseblocks). If the
2631 underlying flash does not admit of bad eraseblocks (e.g. NOR
2632 flash), this value is ignored.
2633
2634 NAND datasheets often specify the minimum and maximum NVM
2635 (Number of Valid Blocks) for the flashes' endurance lifetime.
2636 The maximum expected bad eraseblocks per 1024 eraseblocks
2637 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2638 which gives 20 for most NANDs (MaxNVB is basically the total
2639 count of eraseblocks on the chip).
2640
2641 To put it differently, if this value is 20, UBI will try to
2642 reserve about 1.9% of physical eraseblocks for bad blocks
2643 handling. And that will be 1.9% of eraseblocks on the entire
2644 NAND chip, not just the MTD partition UBI attaches. This means
2645 that if you have, say, a NAND flash chip admits maximum 40 bad
2646 eraseblocks, and it is split on two MTD partitions of the same
2647 size, UBI will reserve 40 eraseblocks when attaching a
2648 partition.
2649
2650 default: 20
2651
2652 CONFIG_MTD_UBI_FASTMAP
2653 Fastmap is a mechanism which allows attaching an UBI device
2654 in nearly constant time. Instead of scanning the whole MTD device it
2655 only has to locate a checkpoint (called fastmap) on the device.
2656 The on-flash fastmap contains all information needed to attach
2657 the device. Using fastmap makes only sense on large devices where
2658 attaching by scanning takes long. UBI will not automatically install
2659 a fastmap on old images, but you can set the UBI parameter
2660 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2661 that fastmap-enabled images are still usable with UBI implementations
2662 without fastmap support. On typical flash devices the whole fastmap
2663 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2664
2665 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2666 Set this parameter to enable fastmap automatically on images
2667 without a fastmap.
2668 default: 0
2669
0195a7bb
HS
2670 CONFIG_MTD_UBI_FM_DEBUG
2671 Enable UBI fastmap debug
2672 default: 0
2673
70c219cd 2674- UBIFS support
147162da
JH
2675 CONFIG_UBIFS_SILENCE_MSG
2676
2677 Make the verbose messages from UBIFS stop printing. This leaves
2678 warnings and errors enabled.
2679
6a11cf48 2680- SPL framework
04e5ae79
WD
2681 CONFIG_SPL
2682 Enable building of SPL globally.
6a11cf48 2683
95579793
TR
2684 CONFIG_SPL_LDSCRIPT
2685 LDSCRIPT for linking the SPL binary.
2686
6ebc3461
AA
2687 CONFIG_SPL_MAX_FOOTPRINT
2688 Maximum size in memory allocated to the SPL, BSS included.
2689 When defined, the linker checks that the actual memory
2690 used by SPL from _start to __bss_end does not exceed it.
8960af8b 2691 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
6ebc3461
AA
2692 must not be both defined at the same time.
2693
95579793 2694 CONFIG_SPL_MAX_SIZE
6ebc3461
AA
2695 Maximum size of the SPL image (text, data, rodata, and
2696 linker lists sections), BSS excluded.
2697 When defined, the linker checks that the actual size does
2698 not exceed it.
95579793 2699
04e5ae79
WD
2700 CONFIG_SPL_TEXT_BASE
2701 TEXT_BASE for linking the SPL binary.
6a11cf48 2702
94a45bb1
SW
2703 CONFIG_SPL_RELOC_TEXT_BASE
2704 Address to relocate to. If unspecified, this is equal to
2705 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2706
95579793
TR
2707 CONFIG_SPL_BSS_START_ADDR
2708 Link address for the BSS within the SPL binary.
2709
2710 CONFIG_SPL_BSS_MAX_SIZE
6ebc3461
AA
2711 Maximum size in memory allocated to the SPL BSS.
2712 When defined, the linker checks that the actual memory used
2713 by SPL from __bss_start to __bss_end does not exceed it.
8960af8b 2714 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
6ebc3461 2715 must not be both defined at the same time.
95579793
TR
2716
2717 CONFIG_SPL_STACK
2718 Adress of the start of the stack SPL will use
2719
8c80eb3b
AA
2720 CONFIG_SPL_PANIC_ON_RAW_IMAGE
2721 When defined, SPL will panic() if the image it has
2722 loaded does not have a signature.
2723 Defining this is useful when code which loads images
2724 in SPL cannot guarantee that absolutely all read errors
2725 will be caught.
2726 An example is the LPC32XX MLC NAND driver, which will
2727 consider that a completely unreadable NAND block is bad,
2728 and thus should be skipped silently.
2729
94a45bb1
SW
2730 CONFIG_SPL_RELOC_STACK
2731 Adress of the start of the stack SPL will use after
2732 relocation. If unspecified, this is equal to
2733 CONFIG_SPL_STACK.
2734
95579793
TR
2735 CONFIG_SYS_SPL_MALLOC_START
2736 Starting address of the malloc pool used in SPL.
9ac4fc82
FE
2737 When this option is set the full malloc is used in SPL and
2738 it is set up by spl_init() and before that, the simple malloc()
2739 can be used if CONFIG_SYS_MALLOC_F is defined.
95579793
TR
2740
2741 CONFIG_SYS_SPL_MALLOC_SIZE
2742 The size of the malloc pool used in SPL.
6a11cf48 2743
47f7bcae
TR
2744 CONFIG_SPL_FRAMEWORK
2745 Enable the SPL framework under common/. This framework
2746 supports MMC, NAND and YMODEM loading of U-Boot and NAND
2747 NAND loading of the Linux Kernel.
2748
9607faf2
TR
2749 CONFIG_SPL_OS_BOOT
2750 Enable booting directly to an OS from SPL.
2751 See also: doc/README.falcon
2752
861a86f4
TR
2753 CONFIG_SPL_DISPLAY_PRINT
2754 For ARM, enable an optional function to print more information
2755 about the running system.
2756
4b919725
SW
2757 CONFIG_SPL_INIT_MINIMAL
2758 Arch init code should be built for a very small image
2759
b97300b6
PK
2760 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2761 Partition on the MMC to load U-Boot from when the MMC is being
2762 used in raw mode
2763
2b75b0ad
PK
2764 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2765 Sector to load kernel uImage from when MMC is being
2766 used in raw mode (for Falcon mode)
2767
2768 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2769 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2770 Sector and number of sectors to load kernel argument
2771 parameters from when MMC is being used in raw mode
2772 (for falcon mode)
2773
e2ccdf89
PK
2774 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2775 Partition on the MMC to load U-Boot from when the MMC is being
2776 used in fs mode
2777
fae81c72
GG
2778 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2779 Filename to read to load U-Boot when reading from filesystem
2780
2781 CONFIG_SPL_FS_LOAD_KERNEL_NAME
7ad2cc79 2782 Filename to read to load kernel uImage when reading
fae81c72 2783 from filesystem (for Falcon mode)
7ad2cc79 2784
fae81c72 2785 CONFIG_SPL_FS_LOAD_ARGS_NAME
7ad2cc79 2786 Filename to read to load kernel argument parameters
fae81c72 2787 when reading from filesystem (for Falcon mode)
7ad2cc79 2788
06f60ae3
SW
2789 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
2790 Set this for NAND SPL on PPC mpc83xx targets, so that
2791 start.S waits for the rest of the SPL to load before
2792 continuing (the hardware starts execution after just
2793 loading the first page rather than the full 4K).
2794
651fcf60
PK
2795 CONFIG_SPL_SKIP_RELOCATE
2796 Avoid SPL relocation
2797
6f2f01b9
SW
2798 CONFIG_SPL_NAND_BASE
2799 Include nand_base.c in the SPL. Requires
2800 CONFIG_SPL_NAND_DRIVERS.
2801
2802 CONFIG_SPL_NAND_DRIVERS
2803 SPL uses normal NAND drivers, not minimal drivers.
2804
2805 CONFIG_SPL_NAND_ECC
2806 Include standard software ECC in the SPL
2807
95579793 2808 CONFIG_SPL_NAND_SIMPLE
7d4b7955
SW
2809 Support for NAND boot using simple NAND drivers that
2810 expose the cmd_ctrl() interface.
95579793 2811
6f4e7d3c
TG
2812 CONFIG_SPL_UBI
2813 Support for a lightweight UBI (fastmap) scanner and
2814 loader
2815
0c3117b1
HS
2816 CONFIG_SPL_NAND_RAW_ONLY
2817 Support to boot only raw u-boot.bin images. Use this only
2818 if you need to save space.
2819
7c8eea59
YZ
2820 CONFIG_SPL_COMMON_INIT_DDR
2821 Set for common ddr init with serial presence detect in
2822 SPL binary.
2823
95579793
TR
2824 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2825 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2826 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2827 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2828 CONFIG_SYS_NAND_ECCBYTES
2829 Defines the size and behavior of the NAND that SPL uses
7d4b7955 2830 to read U-Boot
95579793 2831
fbe76ae4
PK
2832 CONFIG_SPL_NAND_BOOT
2833 Add support NAND boot
2834
95579793 2835 CONFIG_SYS_NAND_U_BOOT_OFFS
7d4b7955
SW
2836 Location in NAND to read U-Boot from
2837
2838 CONFIG_SYS_NAND_U_BOOT_DST
2839 Location in memory to load U-Boot to
2840
2841 CONFIG_SYS_NAND_U_BOOT_SIZE
2842 Size of image to load
95579793
TR
2843
2844 CONFIG_SYS_NAND_U_BOOT_START
7d4b7955 2845 Entry point in loaded image to jump to
95579793
TR
2846
2847 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2848 Define this if you need to first read the OOB and then the
b445bbb4 2849 data. This is used, for example, on davinci platforms.
95579793 2850
c57b953d
PM
2851 CONFIG_SPL_RAM_DEVICE
2852 Support for running image already present in ram, in SPL binary
6a11cf48 2853
74752baa 2854 CONFIG_SPL_PAD_TO
6113d3f2
BT
2855 Image offset to which the SPL should be padded before appending
2856 the SPL payload. By default, this is defined as
2857 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2858 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2859 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
74752baa 2860
ca2fca22
SW
2861 CONFIG_SPL_TARGET
2862 Final target image containing SPL and payload. Some SPLs
2863 use an arch-specific makefile fragment instead, for
2864 example if more than one image needs to be produced.
2865
87ebee39
SG
2866 CONFIG_FIT_SPL_PRINT
2867 Printing information about a FIT image adds quite a bit of
2868 code to SPL. So this is normally disabled in SPL. Use this
2869 option to re-enable it. This will affect the output of the
2870 bootm command when booting a FIT image.
2871
3aa29de0
YZ
2872- TPL framework
2873 CONFIG_TPL
2874 Enable building of TPL globally.
2875
2876 CONFIG_TPL_PAD_TO
2877 Image offset to which the TPL should be padded before appending
2878 the TPL payload. By default, this is defined as
93e14596
WD
2879 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2880 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2881 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3aa29de0 2882
a8c7c708
WD
2883- Interrupt support (PPC):
2884
d4ca31c4
WD
2885 There are common interrupt_init() and timer_interrupt()
2886 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
11ccc33f 2887 for CPU specific initialization. interrupt_init_cpu()
d4ca31c4 2888 should set decrementer_count to appropriate value. If
11ccc33f 2889 CPU resets decrementer automatically after interrupt
d4ca31c4 2890 (ppc4xx) it should set decrementer_count to zero.
11ccc33f 2891 timer_interrupt() calls timer_interrupt_cpu() for CPU
d4ca31c4
WD
2892 specific handling. If board has watchdog / status_led
2893 / other_activity_monitor it works automatically from
2894 general timer_interrupt().
a8c7c708 2895
c609719b 2896
9660e442
HR
2897Board initialization settings:
2898------------------------------
2899
2900During Initialization u-boot calls a number of board specific functions
2901to allow the preparation of board specific prerequisites, e.g. pin setup
2902before drivers are initialized. To enable these callbacks the
2903following configuration macros have to be defined. Currently this is
2904architecture specific, so please check arch/your_architecture/lib/board.c
2905typically in board_init_f() and board_init_r().
2906
2907- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2908- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2909- CONFIG_BOARD_LATE_INIT: Call board_late_init()
2910- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
c609719b 2911
c609719b
WD
2912Configuration Settings:
2913-----------------------
2914
4d1fd7f1
YS
2915- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
2916 Optionally it can be defined to support 64-bit memory commands.
2917
6d0f6bcf 2918- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
c609719b
WD
2919 undefine this when you're short of memory.
2920
2fb2604d
PT
2921- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2922 width of the commands listed in the 'help' command output.
2923
6d0f6bcf 2924- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
c609719b
WD
2925 prompt for user input.
2926
6d0f6bcf 2927- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
c609719b 2928
6d0f6bcf 2929- CONFIG_SYS_PBSIZE: Buffer size for Console output
c609719b 2930
6d0f6bcf 2931- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
c609719b 2932
6d0f6bcf 2933- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
c609719b
WD
2934 the application (usually a Linux kernel) when it is
2935 booted
2936
6d0f6bcf 2937- CONFIG_SYS_BAUDRATE_TABLE:
c609719b
WD
2938 List of legal baudrate settings for this board.
2939
6d0f6bcf 2940- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
c609719b
WD
2941 Begin and End addresses of the area used by the
2942 simple memory test.
2943
6d0f6bcf 2944- CONFIG_SYS_ALT_MEMTEST:
8bde7f77 2945 Enable an alternate, more extensive memory test.
c609719b 2946
6d0f6bcf 2947- CONFIG_SYS_MEMTEST_SCRATCH:
5f535fe1
WD
2948 Scratch address used by the alternate memory test
2949 You only need to set this if address zero isn't writeable
2950
e8149522 2951- CONFIG_SYS_MEM_RESERVE_SECURE
e61a7534 2952 Only implemented for ARMv8 for now.
e8149522
YS
2953 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2954 is substracted from total RAM and won't be reported to OS.
2955 This memory can be used as secure memory. A variable
e61a7534 2956 gd->arch.secure_ram is used to track the location. In systems
e8149522
YS
2957 the RAM base is not zero, or RAM is divided into banks,
2958 this variable needs to be recalcuated to get the address.
2959
aabd7ddb 2960- CONFIG_SYS_MEM_TOP_HIDE:
6d0f6bcf 2961 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
14f73ca6 2962 this specified memory area will get subtracted from the top
11ccc33f 2963 (end) of RAM and won't get "touched" at all by U-Boot. By
14f73ca6
SR
2964 fixing up gd->ram_size the Linux kernel should gets passed
2965 the now "corrected" memory size and won't touch it either.
2966 This should work for arch/ppc and arch/powerpc. Only Linux
5e12e75d 2967 board ports in arch/powerpc with bootwrapper support that
14f73ca6 2968 recalculate the memory size from the SDRAM controller setup
5e12e75d 2969 will have to get fixed in Linux additionally.
14f73ca6
SR
2970
2971 This option can be used as a workaround for the 440EPx/GRx
2972 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2973 be touched.
2974
2975 WARNING: Please make sure that this value is a multiple of
2976 the Linux page size (normally 4k). If this is not the case,
2977 then the end address of the Linux memory will be located at a
2978 non page size aligned address and this could cause major
2979 problems.
2980
6d0f6bcf 2981- CONFIG_SYS_LOADS_BAUD_CHANGE:
c609719b
WD
2982 Enable temporary baudrate change while serial download
2983
6d0f6bcf 2984- CONFIG_SYS_SDRAM_BASE:
c609719b
WD
2985 Physical start address of SDRAM. _Must_ be 0 here.
2986
6d0f6bcf 2987- CONFIG_SYS_FLASH_BASE:
c609719b
WD
2988 Physical start address of Flash memory.
2989
6d0f6bcf 2990- CONFIG_SYS_MONITOR_BASE:
c609719b
WD
2991 Physical start address of boot monitor code (set by
2992 make config files to be same as the text base address
14d0a02a 2993 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
6d0f6bcf 2994 CONFIG_SYS_FLASH_BASE when booting from flash.
c609719b 2995
6d0f6bcf 2996- CONFIG_SYS_MONITOR_LEN:
8bde7f77
WD
2997 Size of memory reserved for monitor code, used to
2998 determine _at_compile_time_ (!) if the environment is
2999 embedded within the U-Boot image, or in a separate
3000 flash sector.
c609719b 3001
6d0f6bcf 3002- CONFIG_SYS_MALLOC_LEN:
c609719b
WD
3003 Size of DRAM reserved for malloc() use.
3004
d59476b6
SG
3005- CONFIG_SYS_MALLOC_F_LEN
3006 Size of the malloc() pool for use before relocation. If
3007 this is defined, then a very simple malloc() implementation
3008 will become available before relocation. The address is just
3009 below the global data, and the stack is moved down to make
3010 space.
3011
3012 This feature allocates regions with increasing addresses
3013 within the region. calloc() is supported, but realloc()
3014 is not available. free() is supported but does nothing.
b445bbb4 3015 The memory will be freed (or in fact just forgotten) when
d59476b6
SG
3016 U-Boot relocates itself.
3017
38687ae6
SG
3018- CONFIG_SYS_MALLOC_SIMPLE
3019 Provides a simple and small malloc() and calloc() for those
3020 boards which do not use the full malloc in SPL (which is
3021 enabled with CONFIG_SYS_SPL_MALLOC_START).
3022
1dfdd9ba
TR
3023- CONFIG_SYS_NONCACHED_MEMORY:
3024 Size of non-cached memory area. This area of memory will be
3025 typically located right below the malloc() area and mapped
3026 uncached in the MMU. This is useful for drivers that would
3027 otherwise require a lot of explicit cache maintenance. For
3028 some drivers it's also impossible to properly maintain the
3029 cache. For example if the regions that need to be flushed
3030 are not a multiple of the cache-line size, *and* padding
3031 cannot be allocated between the regions to align them (i.e.
3032 if the HW requires a contiguous array of regions, and the
3033 size of each region is not cache-aligned), then a flush of
3034 one region may result in overwriting data that hardware has
3035 written to another region in the same cache-line. This can
3036 happen for example in network drivers where descriptors for
3037 buffers are typically smaller than the CPU cache-line (e.g.
3038 16 bytes vs. 32 or 64 bytes).
3039
3040 Non-cached memory is only supported on 32-bit ARM at present.
3041
6d0f6bcf 3042- CONFIG_SYS_BOOTM_LEN:
15940c9a
SR
3043 Normally compressed uImages are limited to an
3044 uncompressed size of 8 MBytes. If this is not enough,
6d0f6bcf 3045 you can define CONFIG_SYS_BOOTM_LEN in your board config file
15940c9a
SR
3046 to adjust this setting to your needs.
3047
6d0f6bcf 3048- CONFIG_SYS_BOOTMAPSZ:
c609719b
WD
3049 Maximum size of memory mapped by the startup code of
3050 the Linux kernel; all data that must be processed by
7d721e34
BS
3051 the Linux kernel (bd_info, boot arguments, FDT blob if
3052 used) must be put below this limit, unless "bootm_low"
1bce2aeb 3053 environment variable is defined and non-zero. In such case
7d721e34 3054 all data for the Linux kernel must be between "bootm_low"
c0f40859 3055 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
c3624e6e
GL
3056 variable "bootm_mapsize" will override the value of
3057 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3058 then the value in "bootm_size" will be used instead.
c609719b 3059
fca43cc8
JR
3060- CONFIG_SYS_BOOT_RAMDISK_HIGH:
3061 Enable initrd_high functionality. If defined then the
3062 initrd_high feature is enabled and the bootm ramdisk subcommand
3063 is enabled.
3064
3065- CONFIG_SYS_BOOT_GET_CMDLINE:
3066 Enables allocating and saving kernel cmdline in space between
3067 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3068
3069- CONFIG_SYS_BOOT_GET_KBD:
3070 Enables allocating and saving a kernel copy of the bd_info in
3071 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3072
6d0f6bcf 3073- CONFIG_SYS_MAX_FLASH_BANKS:
c609719b
WD
3074 Max number of Flash memory banks
3075
6d0f6bcf 3076- CONFIG_SYS_MAX_FLASH_SECT:
c609719b
WD
3077 Max number of sectors on a Flash chip
3078
6d0f6bcf 3079- CONFIG_SYS_FLASH_ERASE_TOUT:
c609719b
WD
3080 Timeout for Flash erase operations (in ms)
3081
6d0f6bcf 3082- CONFIG_SYS_FLASH_WRITE_TOUT:
c609719b
WD
3083 Timeout for Flash write operations (in ms)
3084
6d0f6bcf 3085- CONFIG_SYS_FLASH_LOCK_TOUT
8564acf9
WD
3086 Timeout for Flash set sector lock bit operation (in ms)
3087
6d0f6bcf 3088- CONFIG_SYS_FLASH_UNLOCK_TOUT
8564acf9
WD
3089 Timeout for Flash clear lock bits operation (in ms)
3090
6d0f6bcf 3091- CONFIG_SYS_FLASH_PROTECTION
8564acf9
WD
3092 If defined, hardware flash sectors protection is used
3093 instead of U-Boot software protection.
3094
6d0f6bcf 3095- CONFIG_SYS_DIRECT_FLASH_TFTP:
c609719b
WD
3096
3097 Enable TFTP transfers directly to flash memory;
3098 without this option such a download has to be
3099 performed in two steps: (1) download to RAM, and (2)
3100 copy from RAM to flash.
3101
3102 The two-step approach is usually more reliable, since
3103 you can check if the download worked before you erase
11ccc33f
MZ
3104 the flash, but in some situations (when system RAM is
3105 too limited to allow for a temporary copy of the
c609719b
WD
3106 downloaded image) this option may be very useful.
3107
6d0f6bcf 3108- CONFIG_SYS_FLASH_CFI:
43d9616c 3109 Define if the flash driver uses extra elements in the
5653fc33
WD
3110 common flash structure for storing flash geometry.
3111
00b1883a 3112- CONFIG_FLASH_CFI_DRIVER
5653fc33
WD
3113 This option also enables the building of the cfi_flash driver
3114 in the drivers directory
c609719b 3115
91809ed5
PZ
3116- CONFIG_FLASH_CFI_MTD
3117 This option enables the building of the cfi_mtd driver
3118 in the drivers directory. The driver exports CFI flash
3119 to the MTD layer.
3120
6d0f6bcf 3121- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
96ef831f
GL
3122 Use buffered writes to flash.
3123
3124- CONFIG_FLASH_SPANSION_S29WS_N
3125 s29ws-n MirrorBit flash has non-standard addresses for buffered
3126 write commands.
3127
6d0f6bcf 3128- CONFIG_SYS_FLASH_QUIET_TEST
5568e613
SR
3129 If this option is defined, the common CFI flash doesn't
3130 print it's warning upon not recognized FLASH banks. This
3131 is useful, if some of the configured banks are only
3132 optionally available.
3133
9a042e9c
JVB
3134- CONFIG_FLASH_SHOW_PROGRESS
3135 If defined (must be an integer), print out countdown
3136 digits and dots. Recommended value: 45 (9..1) for 80
3137 column displays, 15 (3..1) for 40 column displays.
3138
352ef3f1
SR
3139- CONFIG_FLASH_VERIFY
3140 If defined, the content of the flash (destination) is compared
3141 against the source after the write operation. An error message
3142 will be printed when the contents are not identical.
3143 Please note that this option is useless in nearly all cases,
3144 since such flash programming errors usually are detected earlier
3145 while unprotecting/erasing/programming. Please only enable
3146 this option if you really know what you are doing.
3147
6d0f6bcf 3148- CONFIG_SYS_RX_ETH_BUFFER:
11ccc33f
MZ
3149 Defines the number of Ethernet receive buffers. On some
3150 Ethernet controllers it is recommended to set this value
53cf9435
SR
3151 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3152 buffers can be full shortly after enabling the interface
11ccc33f 3153 on high Ethernet traffic.
53cf9435
SR
3154 Defaults to 4 if not defined.
3155
ea882baf
WD
3156- CONFIG_ENV_MAX_ENTRIES
3157
071bc923
WD
3158 Maximum number of entries in the hash table that is used
3159 internally to store the environment settings. The default
3160 setting is supposed to be generous and should work in most
3161 cases. This setting can be used to tune behaviour; see
3162 lib/hashtable.c for details.
ea882baf 3163
2598090b
JH
3164- CONFIG_ENV_FLAGS_LIST_DEFAULT
3165- CONFIG_ENV_FLAGS_LIST_STATIC
1bce2aeb 3166 Enable validation of the values given to environment variables when
2598090b
JH
3167 calling env set. Variables can be restricted to only decimal,
3168 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3169 the variables can also be restricted to IP address or MAC address.
3170
3171 The format of the list is:
3172 type_attribute = [s|d|x|b|i|m]
b445bbb4
JM
3173 access_attribute = [a|r|o|c]
3174 attributes = type_attribute[access_attribute]
2598090b
JH
3175 entry = variable_name[:attributes]
3176 list = entry[,list]
3177
3178 The type attributes are:
3179 s - String (default)
3180 d - Decimal
3181 x - Hexadecimal
3182 b - Boolean ([1yYtT|0nNfF])
3183 i - IP address
3184 m - MAC address
3185
267541f7
JH
3186 The access attributes are:
3187 a - Any (default)
3188 r - Read-only
3189 o - Write-once
3190 c - Change-default
3191
2598090b
JH
3192 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3193 Define this to a list (string) to define the ".flags"
b445bbb4 3194 environment variable in the default or embedded environment.
2598090b
JH
3195
3196 - CONFIG_ENV_FLAGS_LIST_STATIC
3197 Define this to a list (string) to define validation that
3198 should be done if an entry is not found in the ".flags"
3199 environment variable. To override a setting in the static
3200 list, simply add an entry for the same variable name to the
3201 ".flags" variable.
3202
bdf1fe4e
JH
3203 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3204 regular expression. This allows multiple variables to define the same
3205 flags without explicitly listing them for each variable.
3206
267541f7
JH
3207- CONFIG_ENV_ACCESS_IGNORE_FORCE
3208 If defined, don't allow the -f switch to env set override variable
3209 access flags.
3210
0d296cc2
GB
3211- CONFIG_USE_STDINT
3212 If stdint.h is available with your toolchain you can define this
3213 option to enable it. You can provide option 'USE_STDINT=1' when
3214 building U-Boot to enable this.
3215
c609719b
WD
3216The following definitions that deal with the placement and management
3217of environment data (variable area); in general, we support the
3218following configurations:
3219
c3eb3fe4
MF
3220- CONFIG_BUILD_ENVCRC:
3221
3222 Builds up envcrc with the target environment so that external utils
3223 may easily extract it and embed it in final U-Boot images.
3224
c609719b 3225BE CAREFUL! The first access to the environment happens quite early
b445bbb4 3226in U-Boot initialization (when we try to get the setting of for the
11ccc33f 3227console baudrate). You *MUST* have mapped your NVRAM area then, or
c609719b
WD
3228U-Boot will hang.
3229
3230Please note that even with NVRAM we still use a copy of the
3231environment in RAM: we could work on NVRAM directly, but we want to
3232keep settings there always unmodified except somebody uses "saveenv"
3233to save the current settings.
3234
0a85a9e7
LG
3235BE CAREFUL! For some special cases, the local device can not use
3236"saveenv" command. For example, the local device will get the
fc54c7fa
LG
3237environment stored in a remote NOR flash by SRIO or PCIE link,
3238but it can not erase, write this NOR flash by SRIO or PCIE interface.
0a85a9e7 3239
b74ab737
GL
3240- CONFIG_NAND_ENV_DST
3241
3242 Defines address in RAM to which the nand_spl code should copy the
3243 environment. If redundant environment is used, it will be copied to
3244 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3245
e881cb56 3246Please note that the environment is read-only until the monitor
c609719b 3247has been relocated to RAM and a RAM copy of the environment has been
00caae6d 3248created; also, when using EEPROM you will have to use env_get_f()
c609719b
WD
3249until then to read environment variables.
3250
85ec0bcc
WD
3251The environment is protected by a CRC32 checksum. Before the monitor
3252is relocated into RAM, as a result of a bad CRC you will be working
3253with the compiled-in default environment - *silently*!!! [This is
3254necessary, because the first environment variable we need is the
3255"baudrate" setting for the console - if we have a bad CRC, we don't
3256have any device yet where we could complain.]
c609719b
WD
3257
3258Note: once the monitor has been relocated, then it will complain if
3259the default environment is used; a new CRC is computed as soon as you
85ec0bcc 3260use the "saveenv" command to store a valid environment.
c609719b 3261
6d0f6bcf 3262- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
42d1f039 3263 Echo the inverted Ethernet link state to the fault LED.
fc3e2165 3264
6d0f6bcf 3265 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
fc3e2165
WD
3266 also needs to be defined.
3267
6d0f6bcf 3268- CONFIG_SYS_FAULT_MII_ADDR:
42d1f039 3269 MII address of the PHY to check for the Ethernet link state.
c609719b 3270
f5675aa5
RM
3271- CONFIG_NS16550_MIN_FUNCTIONS:
3272 Define this if you desire to only have use of the NS16550_init
3273 and NS16550_putc functions for the serial driver located at
3274 drivers/serial/ns16550.c. This option is useful for saving
3275 space for already greatly restricted images, including but not
3276 limited to NAND_SPL configurations.
3277
b2b92f53
SG
3278- CONFIG_DISPLAY_BOARDINFO
3279 Display information about the board that U-Boot is running on
3280 when U-Boot starts up. The board function checkboard() is called
3281 to do this.
3282
e2e3e2b1
SG
3283- CONFIG_DISPLAY_BOARDINFO_LATE
3284 Similar to the previous option, but display this information
3285 later, once stdio is running and output goes to the LCD, if
3286 present.
3287
feb85801
SS
3288- CONFIG_BOARD_SIZE_LIMIT:
3289 Maximum size of the U-Boot image. When defined, the
3290 build system checks that the actual size does not
3291 exceed it.
3292
c609719b 3293Low Level (hardware related) configuration options:
dc7c9a1a 3294---------------------------------------------------
c609719b 3295
6d0f6bcf 3296- CONFIG_SYS_CACHELINE_SIZE:
c609719b
WD
3297 Cache Line Size of the CPU.
3298
e46fedfe
TT
3299- CONFIG_SYS_CCSRBAR_DEFAULT:
3300 Default (power-on reset) physical address of CCSR on Freescale
3301 PowerPC SOCs.
3302
3303- CONFIG_SYS_CCSRBAR:
3304 Virtual address of CCSR. On a 32-bit build, this is typically
3305 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3306
e46fedfe
TT
3307- CONFIG_SYS_CCSRBAR_PHYS:
3308 Physical address of CCSR. CCSR can be relocated to a new
3309 physical address, if desired. In this case, this macro should
c0f40859 3310 be set to that address. Otherwise, it should be set to the
e46fedfe
TT
3311 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3312 is typically relocated on 36-bit builds. It is recommended
3313 that this macro be defined via the _HIGH and _LOW macros:
3314
3315 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3316 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3317
3318- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4cf2609b
WD
3319 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3320 either 0 (32-bit build) or 0xF (36-bit build). This macro is
e46fedfe
TT
3321 used in assembly code, so it must not contain typecasts or
3322 integer size suffixes (e.g. "ULL").
3323
3324- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3325 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3326 used in assembly code, so it must not contain typecasts or
3327 integer size suffixes (e.g. "ULL").
3328
3329- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3330 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3331 forced to a value that ensures that CCSR is not relocated.
3332
7f6c2cbc 3333- Floppy Disk Support:
6d0f6bcf 3334 CONFIG_SYS_FDC_DRIVE_NUMBER
7f6c2cbc
WD
3335
3336 the default drive number (default value 0)
3337
6d0f6bcf 3338 CONFIG_SYS_ISA_IO_STRIDE
7f6c2cbc 3339
11ccc33f 3340 defines the spacing between FDC chipset registers
7f6c2cbc
WD
3341 (default value 1)
3342
6d0f6bcf 3343 CONFIG_SYS_ISA_IO_OFFSET
7f6c2cbc 3344
43d9616c
WD
3345 defines the offset of register from address. It
3346 depends on which part of the data bus is connected to
11ccc33f 3347 the FDC chipset. (default value 0)
7f6c2cbc 3348
6d0f6bcf
JCPV
3349 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3350 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
43d9616c 3351 default value.
7f6c2cbc 3352
6d0f6bcf 3353 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
43d9616c
WD
3354 fdc_hw_init() is called at the beginning of the FDC
3355 setup. fdc_hw_init() must be provided by the board
b445bbb4 3356 source code. It is used to make hardware-dependent
43d9616c 3357 initializations.
7f6c2cbc 3358
0abddf82
ML
3359- CONFIG_IDE_AHB:
3360 Most IDE controllers were designed to be connected with PCI
3361 interface. Only few of them were designed for AHB interface.
3362 When software is doing ATA command and data transfer to
3363 IDE devices through IDE-AHB controller, some additional
3364 registers accessing to these kind of IDE-AHB controller
b445bbb4 3365 is required.
0abddf82 3366
6d0f6bcf 3367- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
efe2a4d5 3368 DO NOT CHANGE unless you know exactly what you're
907208c4 3369 doing! (11-4) [MPC8xx systems only]
c609719b 3370
6d0f6bcf 3371- CONFIG_SYS_INIT_RAM_ADDR:
c609719b 3372
7152b1d0 3373 Start address of memory area that can be used for
c609719b
WD
3374 initial data and stack; please note that this must be
3375 writable memory that is working WITHOUT special
3376 initialization, i. e. you CANNOT use normal RAM which
3377 will become available only after programming the
3378 memory controller and running certain initialization
3379 sequences.
3380
3381 U-Boot uses the following memory types:
907208c4 3382 - MPC8xx: IMMR (internal memory of the CPU)
c609719b 3383
6d0f6bcf 3384- CONFIG_SYS_GBL_DATA_OFFSET:
c609719b
WD
3385
3386 Offset of the initial data structure in the memory
6d0f6bcf
JCPV
3387 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3388 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
c609719b 3389 data is located at the end of the available space
553f0982 3390 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
acd51f9d 3391 GENERATED_GBL_DATA_SIZE), and the initial stack is just
6d0f6bcf
JCPV
3392 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3393 CONFIG_SYS_GBL_DATA_OFFSET) downward.
c609719b
WD
3394
3395 Note:
3396 On the MPC824X (or other systems that use the data
3397 cache for initial memory) the address chosen for
6d0f6bcf 3398 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
c609719b
WD
3399 point to an otherwise UNUSED address space between
3400 the top of RAM and the start of the PCI space.
3401
6d0f6bcf 3402- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
c609719b 3403
6d0f6bcf 3404- CONFIG_SYS_OR_TIMING_SDRAM:
c609719b
WD
3405 SDRAM timing
3406
6d0f6bcf 3407- CONFIG_SYS_MAMR_PTA:
c609719b
WD
3408 periodic timer for refresh
3409
6d0f6bcf
JCPV
3410- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3411 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3412 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3413 CONFIG_SYS_BR1_PRELIM:
c609719b
WD
3414 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3415
3416- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
6d0f6bcf
JCPV
3417 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3418 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
c609719b
WD
3419 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3420
69fd2d3b 3421- CONFIG_PCI_ENUM_ONLY
b445bbb4 3422 Only scan through and get the devices on the buses.
69fd2d3b
AS
3423 Don't do any setup work, presumably because someone or
3424 something has already done it, and we don't need to do it
3425 a second time. Useful for platforms that are pre-booted
3426 by coreboot or similar.
3427
842033e6
GJ
3428- CONFIG_PCI_INDIRECT_BRIDGE:
3429 Enable support for indirect PCI bridges.
3430
a09b9b68
KG
3431- CONFIG_SYS_SRIO:
3432 Chip has SRIO or not
3433
3434- CONFIG_SRIO1:
3435 Board has SRIO 1 port available
3436
3437- CONFIG_SRIO2:
3438 Board has SRIO 2 port available
3439
c8b28152
LG
3440- CONFIG_SRIO_PCIE_BOOT_MASTER
3441 Board can support master function for Boot from SRIO and PCIE
3442
a09b9b68
KG
3443- CONFIG_SYS_SRIOn_MEM_VIRT:
3444 Virtual Address of SRIO port 'n' memory region
3445
3446- CONFIG_SYS_SRIOn_MEM_PHYS:
3447 Physical Address of SRIO port 'n' memory region
3448
3449- CONFIG_SYS_SRIOn_MEM_SIZE:
3450 Size of SRIO port 'n' memory region
3451
66bd1846
FE
3452- CONFIG_SYS_NAND_BUSWIDTH_16BIT
3453 Defined to tell the NAND controller that the NAND chip is using
3454 a 16 bit bus.
3455 Not all NAND drivers use this symbol.
a430e916 3456 Example of drivers that use it:
66bd1846 3457 - drivers/mtd/nand/ndfc.c
a430e916 3458 - drivers/mtd/nand/mxc_nand.c
eced4626
AW
3459
3460- CONFIG_SYS_NDFC_EBC0_CFG
3461 Sets the EBC0_CFG register for the NDFC. If not defined
3462 a default value will be used.
3463
bb99ad6d 3464- CONFIG_SPD_EEPROM
218ca724
WD
3465 Get DDR timing information from an I2C EEPROM. Common
3466 with pluggable memory modules such as SODIMMs
3467
bb99ad6d
BW
3468 SPD_EEPROM_ADDRESS
3469 I2C address of the SPD EEPROM
3470
6d0f6bcf 3471- CONFIG_SYS_SPD_BUS_NUM
218ca724
WD
3472 If SPD EEPROM is on an I2C bus other than the first
3473 one, specify here. Note that the value must resolve
3474 to something your driver can deal with.
bb99ad6d 3475
1b3e3c4f
YS
3476- CONFIG_SYS_DDR_RAW_TIMING
3477 Get DDR timing information from other than SPD. Common with
3478 soldered DDR chips onboard without SPD. DDR raw timing
3479 parameters are extracted from datasheet and hard-coded into
3480 header files or board specific files.
3481
6f5e1dc5
YS
3482- CONFIG_FSL_DDR_INTERACTIVE
3483 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3484
e32d59a2
YS
3485- CONFIG_FSL_DDR_SYNC_REFRESH
3486 Enable sync of refresh for multiple controllers.
3487
4516ff81
YS
3488- CONFIG_FSL_DDR_BIST
3489 Enable built-in memory test for Freescale DDR controllers.
3490
6d0f6bcf 3491- CONFIG_SYS_83XX_DDR_USES_CS0
218ca724
WD
3492 Only for 83xx systems. If specified, then DDR should
3493 be configured using CS0 and CS1 instead of CS2 and CS3.
2ad6b513 3494
c26e454d
WD
3495- CONFIG_RMII
3496 Enable RMII mode for all FECs.
3497 Note that this is a global option, we can't
3498 have one FEC in standard MII mode and another in RMII mode.
3499
5cf91d6b
WD
3500- CONFIG_CRC32_VERIFY
3501 Add a verify option to the crc32 command.
3502 The syntax is:
3503
3504 => crc32 -v <address> <count> <crc32>
3505
3506 Where address/count indicate a memory area
3507 and crc32 is the correct crc32 which the
3508 area should have.
3509
56523f12
WD
3510- CONFIG_LOOPW
3511 Add the "loopw" memory command. This only takes effect if
493f420e 3512 the memory commands are activated globally (CONFIG_CMD_MEMORY).
56523f12 3513
7b466641
SR
3514- CONFIG_MX_CYCLIC
3515 Add the "mdc" and "mwc" memory commands. These are cyclic
3516 "md/mw" commands.
3517 Examples:
3518
efe2a4d5 3519 => mdc.b 10 4 500
7b466641
SR
3520 This command will print 4 bytes (10,11,12,13) each 500 ms.
3521
efe2a4d5 3522 => mwc.l 100 12345678 10
7b466641
SR
3523 This command will write 12345678 to address 100 all 10 ms.
3524
efe2a4d5 3525 This only takes effect if the memory commands are activated
493f420e 3526 globally (CONFIG_CMD_MEMORY).
7b466641 3527
8aa1a2d1 3528- CONFIG_SKIP_LOWLEVEL_INIT
afc1ce82 3529 [ARM, NDS32, MIPS only] If this variable is defined, then certain
844f07d8
WD
3530 low level initializations (like setting up the memory
3531 controller) are omitted and/or U-Boot does not
3532 relocate itself into RAM.
3533
3534 Normally this variable MUST NOT be defined. The only
3535 exception is when U-Boot is loaded (to RAM) by some
3536 other boot loader or by a debugger which performs
3537 these initializations itself.
8aa1a2d1 3538
b5bd0982
SG
3539- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3540 [ARM926EJ-S only] This allows just the call to lowlevel_init()
90211f77 3541 to be skipped. The normal CP15 init (such as enabling the
b5bd0982
SG
3542 instruction cache) is still performed.
3543
401bb30b 3544- CONFIG_SPL_BUILD
df81238b
ML
3545 Modifies the behaviour of start.S when compiling a loader
3546 that is executed before the actual U-Boot. E.g. when
3547 compiling a NAND SPL.
400558b5 3548
3aa29de0
YZ
3549- CONFIG_TPL_BUILD
3550 Modifies the behaviour of start.S when compiling a loader
3551 that is executed after the SPL and before the actual U-Boot.
3552 It is loaded by the SPL.
3553
5df572f0
YZ
3554- CONFIG_SYS_MPC85XX_NO_RESETVEC
3555 Only for 85xx systems. If this variable is specified, the section
3556 .resetvec is not kept and the section .bootpg is placed in the
3557 previous 4k of the .text section.
3558
4213fc29
SG
3559- CONFIG_ARCH_MAP_SYSMEM
3560 Generally U-Boot (and in particular the md command) uses
3561 effective address. It is therefore not necessary to regard
3562 U-Boot address as virtual addresses that need to be translated
3563 to physical addresses. However, sandbox requires this, since
3564 it maintains its own little RAM buffer which contains all
3565 addressable memory. This option causes some memory accesses
3566 to be mapped through map_sysmem() / unmap_sysmem().
3567
588a13f7
SG
3568- CONFIG_X86_RESET_VECTOR
3569 If defined, the x86 reset vector code is included. This is not
3570 needed when U-Boot is running from Coreboot.
b16f521a 3571
16678eb4
HS
3572- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
3573 Enables the RTC32K OSC on AM33xx based plattforms
3574
999d7d32
KM
3575- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3576 Option to disable subpage write in NAND driver
3577 driver that uses this:
3578 drivers/mtd/nand/davinci_nand.c
3579
f2717b47
TT
3580Freescale QE/FMAN Firmware Support:
3581-----------------------------------
3582
3583The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3584loading of "firmware", which is encoded in the QE firmware binary format.
3585This firmware often needs to be loaded during U-Boot booting, so macros
3586are used to identify the storage device (NOR flash, SPI, etc) and the address
3587within that device.
3588
dcf1d774
ZQ
3589- CONFIG_SYS_FMAN_FW_ADDR
3590 The address in the storage device where the FMAN microcode is located. The
3591 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3592 is also specified.
3593
3594- CONFIG_SYS_QE_FW_ADDR
3595 The address in the storage device where the QE microcode is located. The
f2717b47
TT
3596 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3597 is also specified.
3598
3599- CONFIG_SYS_QE_FMAN_FW_LENGTH
3600 The maximum possible size of the firmware. The firmware binary format
3601 has a field that specifies the actual size of the firmware, but it
3602 might not be possible to read any part of the firmware unless some
3603 local storage is allocated to hold the entire firmware first.
3604
3605- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3606 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3607 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3608 virtual address in NOR flash.
3609
3610- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3611 Specifies that QE/FMAN firmware is located in NAND flash.
3612 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3613
3614- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3615 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3616 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3617
292dc6c5
LG
3618- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3619 Specifies that QE/FMAN firmware is located in the remote (master)
3620 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
fc54c7fa
LG
3621 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3622 window->master inbound window->master LAW->the ucode address in
3623 master's memory space.
f2717b47 3624
b940ca64
GR
3625Freescale Layerscape Management Complex Firmware Support:
3626---------------------------------------------------------
3627The Freescale Layerscape Management Complex (MC) supports the loading of
3628"firmware".
3629This firmware often needs to be loaded during U-Boot booting, so macros
3630are used to identify the storage device (NOR flash, SPI, etc) and the address
3631within that device.
3632
3633- CONFIG_FSL_MC_ENET
3634 Enable the MC driver for Layerscape SoCs.
3635
5c055089
PK
3636Freescale Layerscape Debug Server Support:
3637-------------------------------------------
3638The Freescale Layerscape Debug Server Support supports the loading of
3639"Debug Server firmware" and triggering SP boot-rom.
3640This firmware often needs to be loaded during U-Boot booting.
3641
c0492141
YS
3642- CONFIG_SYS_MC_RSV_MEM_ALIGN
3643 Define alignment of reserved memory MC requires
5c055089 3644
f3f431a7
PK
3645Reproducible builds
3646-------------------
3647
3648In order to achieve reproducible builds, timestamps used in the U-Boot build
3649process have to be set to a fixed value.
3650
3651This is done using the SOURCE_DATE_EPOCH environment variable.
3652SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3653option for U-Boot or an environment variable in U-Boot.
3654
3655SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3656
c609719b
WD
3657Building the Software:
3658======================
3659
218ca724
WD
3660Building U-Boot has been tested in several native build environments
3661and in many different cross environments. Of course we cannot support
3662all possibly existing versions of cross development tools in all
3663(potentially obsolete) versions. In case of tool chain problems we
3664recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3665which is extensively used to build and test U-Boot.
c609719b 3666
218ca724
WD
3667If you are not using a native environment, it is assumed that you
3668have GNU cross compiling tools available in your path. In this case,
3669you must set the environment variable CROSS_COMPILE in your shell.
3670Note that no changes to the Makefile or any other source files are
3671necessary. For example using the ELDK on a 4xx CPU, please enter:
c609719b 3672
218ca724
WD
3673 $ CROSS_COMPILE=ppc_4xx-
3674 $ export CROSS_COMPILE
c609719b 3675
2f8d396b
PT
3676Note: If you wish to generate Windows versions of the utilities in
3677 the tools directory you can use the MinGW toolchain
3678 (http://www.mingw.org). Set your HOST tools to the MinGW
3679 toolchain and execute 'make tools'. For example:
3680
3681 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3682
3683 Binaries such as tools/mkimage.exe will be created which can
3684 be executed on computers running Windows.
3685
218ca724
WD
3686U-Boot is intended to be simple to build. After installing the
3687sources you must configure U-Boot for one specific board type. This
c609719b
WD
3688is done by typing:
3689
ab584d67 3690 make NAME_defconfig
c609719b 3691
ab584d67 3692where "NAME_defconfig" is the name of one of the existing configu-
4d675ae6 3693rations; see boards.cfg for supported names.
db01a2ea 3694
2729af9d
WD
3695Note: for some board special configuration names may exist; check if
3696 additional information is available from the board vendor; for
3697 instance, the TQM823L systems are available without (standard)
3698 or with LCD support. You can select such additional "features"
11ccc33f 3699 when choosing the configuration, i. e.
2729af9d 3700
ab584d67 3701 make TQM823L_defconfig
2729af9d
WD
3702 - will configure for a plain TQM823L, i. e. no LCD support
3703
ab584d67 3704 make TQM823L_LCD_defconfig
2729af9d
WD
3705 - will configure for a TQM823L with U-Boot console on LCD
3706
3707 etc.
3708
3709
3710Finally, type "make all", and you should get some working U-Boot
3711images ready for download to / installation on your system:
3712
3713- "u-boot.bin" is a raw binary image
3714- "u-boot" is an image in ELF binary format
3715- "u-boot.srec" is in Motorola S-Record format
3716
baf31249
MB
3717By default the build is performed locally and the objects are saved
3718in the source directory. One of the two methods can be used to change
3719this behavior and build U-Boot to some external directory:
3720
37211. Add O= to the make command line invocations:
3722
3723 make O=/tmp/build distclean
ab584d67 3724 make O=/tmp/build NAME_defconfig
baf31249
MB
3725 make O=/tmp/build all
3726
adbba996 37272. Set environment variable KBUILD_OUTPUT to point to the desired location:
baf31249 3728
adbba996 3729 export KBUILD_OUTPUT=/tmp/build
baf31249 3730 make distclean
ab584d67 3731 make NAME_defconfig
baf31249
MB
3732 make all
3733
adbba996 3734Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
baf31249
MB
3735variable.
3736
2729af9d
WD
3737
3738Please be aware that the Makefiles assume you are using GNU make, so
3739for instance on NetBSD you might need to use "gmake" instead of
3740native "make".
3741
3742
3743If the system board that you have is not listed, then you will need
3744to port U-Boot to your hardware platform. To do this, follow these
3745steps:
3746
3c1496cd 37471. Create a new directory to hold your board specific code. Add any
2729af9d 3748 files you need. In your board directory, you will need at least
3c1496cd
PS
3749 the "Makefile" and a "<board>.c".
37502. Create a new configuration file "include/configs/<board>.h" for
3751 your board.
2729af9d
WD
37523. If you're porting U-Boot to a new CPU, then also create a new
3753 directory to hold your CPU specific code. Add any files you need.
ab584d67 37544. Run "make <board>_defconfig" with your new name.
2729af9d
WD
37555. Type "make", and you should get a working "u-boot.srec" file
3756 to be installed on your target system.
37576. Debug and solve any problems that might arise.
3758 [Of course, this last step is much harder than it sounds.]
3759
3760
3761Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3762==============================================================
3763
218ca724
WD
3764If you have modified U-Boot sources (for instance added a new board
3765or support for new devices, a new CPU, etc.) you are expected to
2729af9d
WD
3766provide feedback to the other developers. The feedback normally takes
3767the form of a "patch", i. e. a context diff against a certain (latest
218ca724 3768official or latest in the git repository) version of U-Boot sources.
2729af9d 3769
218ca724
WD
3770But before you submit such a patch, please verify that your modifi-
3771cation did not break existing code. At least make sure that *ALL* of
2729af9d 3772the supported boards compile WITHOUT ANY compiler warnings. To do so,
6de80f21
SG
3773just run the buildman script (tools/buildman/buildman), which will
3774configure and build U-Boot for ALL supported system. Be warned, this
3775will take a while. Please see the buildman README, or run 'buildman -H'
3776for documentation.
baf31249
MB
3777
3778
2729af9d
WD
3779See also "U-Boot Porting Guide" below.
3780
3781
3782Monitor Commands - Overview:
3783============================
3784
3785go - start application at address 'addr'
3786run - run commands in an environment variable
3787bootm - boot application image from memory
3788bootp - boot image via network using BootP/TFTP protocol
44f074c7 3789bootz - boot zImage from memory
2729af9d
WD
3790tftpboot- boot image via network using TFTP protocol
3791 and env variables "ipaddr" and "serverip"
3792 (and eventually "gatewayip")
1fb7cd49 3793tftpput - upload a file via network using TFTP protocol
2729af9d
WD
3794rarpboot- boot image via network using RARP/TFTP protocol
3795diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3796loads - load S-Record file over serial line
3797loadb - load binary file over serial line (kermit mode)
3798md - memory display
3799mm - memory modify (auto-incrementing)
3800nm - memory modify (constant address)
3801mw - memory write (fill)
3802cp - memory copy
3803cmp - memory compare
3804crc32 - checksum calculation
0f89c54b 3805i2c - I2C sub-system
2729af9d
WD
3806sspi - SPI utility commands
3807base - print or set address offset
3808printenv- print environment variables
3809setenv - set environment variables
3810saveenv - save environment variables to persistent storage
3811protect - enable or disable FLASH write protection
3812erase - erase FLASH memory
3813flinfo - print FLASH memory information
10635afa 3814nand - NAND memory operations (see doc/README.nand)
2729af9d
WD
3815bdinfo - print Board Info structure
3816iminfo - print header information for application image
3817coninfo - print console devices and informations
3818ide - IDE sub-system
3819loop - infinite loop on address range
56523f12 3820loopw - infinite write loop on address range
2729af9d
WD
3821mtest - simple RAM test
3822icache - enable or disable instruction cache
3823dcache - enable or disable data cache
3824reset - Perform RESET of the CPU
3825echo - echo args to console
3826version - print monitor version
3827help - print online help
3828? - alias for 'help'
3829
3830
3831Monitor Commands - Detailed Description:
3832========================================
3833
3834TODO.
3835
3836For now: just type "help <command>".
3837
3838
3839Environment Variables:
3840======================
3841
3842U-Boot supports user configuration using Environment Variables which
3843can be made persistent by saving to Flash memory.
c609719b 3844
2729af9d
WD
3845Environment Variables are set using "setenv", printed using
3846"printenv", and saved to Flash using "saveenv". Using "setenv"
3847without a value can be used to delete a variable from the
3848environment. As long as you don't save the environment you are
3849working with an in-memory copy. In case the Flash area containing the
3850environment is erased by accident, a default environment is provided.
c609719b 3851
c96f86ee
WD
3852Some configuration options can be set using Environment Variables.
3853
3854List of environment variables (most likely not complete):
c609719b 3855
2729af9d 3856 baudrate - see CONFIG_BAUDRATE
c609719b 3857
2729af9d 3858 bootdelay - see CONFIG_BOOTDELAY
c609719b 3859
2729af9d 3860 bootcmd - see CONFIG_BOOTCOMMAND
4a6fd34b 3861
2729af9d 3862 bootargs - Boot arguments when booting an RTOS image
c609719b 3863
2729af9d 3864 bootfile - Name of the image to load with TFTP
c609719b 3865
7d721e34
BS
3866 bootm_low - Memory range available for image processing in the bootm
3867 command can be restricted. This variable is given as
3868 a hexadecimal number and defines lowest address allowed
3869 for use by the bootm command. See also "bootm_size"
3870 environment variable. Address defined by "bootm_low" is
3871 also the base of the initial memory mapping for the Linux
c3624e6e
GL
3872 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3873 bootm_mapsize.
3874
c0f40859 3875 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
c3624e6e
GL
3876 This variable is given as a hexadecimal number and it
3877 defines the size of the memory region starting at base
3878 address bootm_low that is accessible by the Linux kernel
3879 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3880 as the default value if it is defined, and bootm_size is
3881 used otherwise.
7d721e34
BS
3882
3883 bootm_size - Memory range available for image processing in the bootm
3884 command can be restricted. This variable is given as
3885 a hexadecimal number and defines the size of the region
3886 allowed for use by the bootm command. See also "bootm_low"
3887 environment variable.
3888
4bae9090
BS
3889 updatefile - Location of the software update file on a TFTP server, used
3890 by the automatic software update feature. Please refer to
3891 documentation in doc/README.update for more details.
3892
2729af9d
WD
3893 autoload - if set to "no" (any string beginning with 'n'),
3894 "bootp" will just load perform a lookup of the
3895 configuration from the BOOTP server, but not try to
3896 load any image using TFTP
c609719b 3897
2729af9d
WD
3898 autostart - if set to "yes", an image loaded using the "bootp",
3899 "rarpboot", "tftpboot" or "diskboot" commands will
3900 be automatically started (by internally calling
3901 "bootm")
38b99261 3902
2729af9d
WD
3903 If set to "no", a standalone image passed to the
3904 "bootm" command will be copied to the load address
3905 (and eventually uncompressed), but NOT be started.
3906 This can be used to load and uncompress arbitrary
3907 data.
c609719b 3908
a28afca5
DL
3909 fdt_high - if set this restricts the maximum address that the
3910 flattened device tree will be copied into upon boot.
fa34f6b2
SG
3911 For example, if you have a system with 1 GB memory
3912 at physical address 0x10000000, while Linux kernel
3913 only recognizes the first 704 MB as low memory, you
3914 may need to set fdt_high as 0x3C000000 to have the
3915 device tree blob be copied to the maximum address
3916 of the 704 MB low memory, so that Linux kernel can
3917 access it during the boot procedure.
3918
a28afca5
DL
3919 If this is set to the special value 0xFFFFFFFF then
3920 the fdt will not be copied at all on boot. For this
3921 to work it must reside in writable memory, have
3922 sufficient padding on the end of it for u-boot to
3923 add the information it needs into it, and the memory
3924 must be accessible by the kernel.
3925
eea63e05
SG
3926 fdtcontroladdr- if set this is the address of the control flattened
3927 device tree used by U-Boot when CONFIG_OF_CONTROL is
3928 defined.
3929
17ea1177
WD
3930 i2cfast - (PPC405GP|PPC405EP only)
3931 if set to 'y' configures Linux I2C driver for fast
3932 mode (400kHZ). This environment variable is used in
3933 initialization code. So, for changes to be effective
3934 it must be saved and board must be reset.
3935
2729af9d
WD
3936 initrd_high - restrict positioning of initrd images:
3937 If this variable is not set, initrd images will be
3938 copied to the highest possible address in RAM; this
3939 is usually what you want since it allows for
3940 maximum initrd size. If for some reason you want to
3941 make sure that the initrd image is loaded below the
6d0f6bcf 3942 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
2729af9d
WD
3943 variable to a value of "no" or "off" or "0".
3944 Alternatively, you can set it to a maximum upper
3945 address to use (U-Boot will still check that it
3946 does not overwrite the U-Boot stack and data).
c609719b 3947
2729af9d
WD
3948 For instance, when you have a system with 16 MB
3949 RAM, and want to reserve 4 MB from use by Linux,
3950 you can do this by adding "mem=12M" to the value of
3951 the "bootargs" variable. However, now you must make
3952 sure that the initrd image is placed in the first
3953 12 MB as well - this can be done with
c609719b 3954
2729af9d 3955 setenv initrd_high 00c00000
c609719b 3956
2729af9d
WD
3957 If you set initrd_high to 0xFFFFFFFF, this is an
3958 indication to U-Boot that all addresses are legal
3959 for the Linux kernel, including addresses in flash
3960 memory. In this case U-Boot will NOT COPY the
3961 ramdisk at all. This may be useful to reduce the
3962 boot time on your system, but requires that this
3963 feature is supported by your Linux kernel.
c609719b 3964
2729af9d 3965 ipaddr - IP address; needed for tftpboot command
c609719b 3966
2729af9d
WD
3967 loadaddr - Default load address for commands like "bootp",
3968 "rarpboot", "tftpboot", "loadb" or "diskboot"
c609719b 3969
2729af9d 3970 loads_echo - see CONFIG_LOADS_ECHO
a3d991bd 3971
2729af9d 3972 serverip - TFTP server IP address; needed for tftpboot command
a3d991bd 3973
2729af9d 3974 bootretry - see CONFIG_BOOT_RETRY_TIME
a3d991bd 3975
2729af9d 3976 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
a3d991bd 3977
2729af9d 3978 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
c609719b 3979
e2a53458 3980 ethprime - controls which interface is used first.
c609719b 3981
e2a53458
MF
3982 ethact - controls which interface is currently active.
3983 For example you can do the following
c609719b 3984
48690d80
HS
3985 => setenv ethact FEC
3986 => ping 192.168.0.1 # traffic sent on FEC
3987 => setenv ethact SCC
3988 => ping 10.0.0.1 # traffic sent on SCC
c609719b 3989
e1692577
MF
3990 ethrotate - When set to "no" U-Boot does not go through all
3991 available network interfaces.
3992 It just stays at the currently selected interface.
3993
c96f86ee 3994 netretry - When set to "no" each network operation will
2729af9d
WD
3995 either succeed or fail without retrying.
3996 When set to "once" the network operation will
3997 fail when all the available network interfaces
3998 are tried once without success.
3999 Useful on scripts which control the retry operation
4000 themselves.
c609719b 4001
b4e2f89d 4002 npe_ucode - set load address for the NPE microcode
a1cf027a 4003
b445bbb4 4004 silent_linux - If set then Linux will be told to boot silently, by
8d51aacd
SG
4005 changing the console to be empty. If "yes" it will be
4006 made silent. If "no" it will not be made silent. If
4007 unset, then it will be made silent if the U-Boot console
4008 is silent.
4009
f5fb7346 4010 tftpsrcp - If this is set, the value is used for TFTP's
ecb0ccd9
WD
4011 UDP source port.
4012
f5fb7346 4013 tftpdstp - If this is set, the value is used for TFTP's UDP
28cb9375
WD
4014 destination port instead of the Well Know Port 69.
4015
c96f86ee
WD
4016 tftpblocksize - Block size to use for TFTP transfers; if not set,
4017 we use the TFTP server's default block size
4018
4019 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4020 seconds, minimum value is 1000 = 1 second). Defines
4021 when a packet is considered to be lost so it has to
4022 be retransmitted. The default is 5000 = 5 seconds.
4023 Lowering this value may make downloads succeed
4024 faster in networks with high packet loss rates or
4025 with unreliable TFTP servers.
4026
f5fb7346
AA
4027 tftptimeoutcountmax - maximum count of TFTP timeouts (no
4028 unit, minimum value = 0). Defines how many timeouts
4029 can happen during a single file transfer before that
4030 transfer is aborted. The default is 10, and 0 means
4031 'no timeouts allowed'. Increasing this value may help
4032 downloads succeed with high packet loss rates, or with
4033 unreliable TFTP servers or client hardware.
4034
c96f86ee 4035 vlan - When set to a value < 4095 the traffic over
11ccc33f 4036 Ethernet is encapsulated/received over 802.1q
2729af9d 4037 VLAN tagged frames.
c609719b 4038
50768f5b
AM
4039 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
4040 Unsigned value, in milliseconds. If not set, the period will
4041 be either the default (28000), or a value based on
4042 CONFIG_NET_RETRY_COUNT, if defined. This value has
4043 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
4044
dc0b7b0e
JH
4045The following image location variables contain the location of images
4046used in booting. The "Image" column gives the role of the image and is
4047not an environment variable name. The other columns are environment
4048variable names. "File Name" gives the name of the file on a TFTP
4049server, "RAM Address" gives the location in RAM the image will be
4050loaded to, and "Flash Location" gives the image's address in NOR
4051flash or offset in NAND flash.
4052
4053*Note* - these variables don't have to be defined for all boards, some
aed9fed9 4054boards currently use other variables for these purposes, and some
dc0b7b0e
JH
4055boards use these variables for other purposes.
4056
c0f40859
WD
4057Image File Name RAM Address Flash Location
4058----- --------- ----------- --------------
4059u-boot u-boot u-boot_addr_r u-boot_addr
4060Linux kernel bootfile kernel_addr_r kernel_addr
4061device tree blob fdtfile fdt_addr_r fdt_addr
4062ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
dc0b7b0e 4063
2729af9d
WD
4064The following environment variables may be used and automatically
4065updated by the network boot commands ("bootp" and "rarpboot"),
4066depending the information provided by your boot server:
c609719b 4067
2729af9d
WD
4068 bootfile - see above
4069 dnsip - IP address of your Domain Name Server
4070 dnsip2 - IP address of your secondary Domain Name Server
4071 gatewayip - IP address of the Gateway (Router) to use
4072 hostname - Target hostname
4073 ipaddr - see above
4074 netmask - Subnet Mask
4075 rootpath - Pathname of the root filesystem on the NFS server
4076 serverip - see above
c1551ea8 4077
c1551ea8 4078
2729af9d 4079There are two special Environment Variables:
c1551ea8 4080
2729af9d
WD
4081 serial# - contains hardware identification information such
4082 as type string and/or serial number
4083 ethaddr - Ethernet address
c609719b 4084
2729af9d
WD
4085These variables can be set only once (usually during manufacturing of
4086the board). U-Boot refuses to delete or overwrite these variables
4087once they have been set once.
c609719b 4088
f07771cc 4089
2729af9d 4090Further special Environment Variables:
f07771cc 4091
2729af9d
WD
4092 ver - Contains the U-Boot version string as printed
4093 with the "version" command. This variable is
4094 readonly (see CONFIG_VERSION_VARIABLE).
f07771cc 4095
f07771cc 4096
2729af9d
WD
4097Please note that changes to some configuration parameters may take
4098only effect after the next boot (yes, that's just like Windoze :-).
f07771cc 4099
f07771cc 4100
170ab110
JH
4101Callback functions for environment variables:
4102---------------------------------------------
4103
4104For some environment variables, the behavior of u-boot needs to change
b445bbb4 4105when their values are changed. This functionality allows functions to
170ab110
JH
4106be associated with arbitrary variables. On creation, overwrite, or
4107deletion, the callback will provide the opportunity for some side
4108effect to happen or for the change to be rejected.
4109
4110The callbacks are named and associated with a function using the
4111U_BOOT_ENV_CALLBACK macro in your board or driver code.
4112
4113These callbacks are associated with variables in one of two ways. The
4114static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4115in the board configuration to a string that defines a list of
4116associations. The list must be in the following format:
4117
4118 entry = variable_name[:callback_name]
4119 list = entry[,list]
4120
4121If the callback name is not specified, then the callback is deleted.
4122Spaces are also allowed anywhere in the list.
4123
4124Callbacks can also be associated by defining the ".callbacks" variable
4125with the same list format above. Any association in ".callbacks" will
4126override any association in the static list. You can define
4127CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
b445bbb4 4128".callbacks" environment variable in the default or embedded environment.
170ab110 4129
bdf1fe4e
JH
4130If CONFIG_REGEX is defined, the variable_name above is evaluated as a
4131regular expression. This allows multiple variables to be connected to
4132the same callback without explicitly listing them all out.
4133
170ab110 4134
2729af9d
WD
4135Command Line Parsing:
4136=====================
f07771cc 4137
2729af9d
WD
4138There are two different command line parsers available with U-Boot:
4139the old "simple" one, and the much more powerful "hush" shell:
c609719b 4140
2729af9d
WD
4141Old, simple command line parser:
4142--------------------------------
c609719b 4143
2729af9d
WD
4144- supports environment variables (through setenv / saveenv commands)
4145- several commands on one line, separated by ';'
fe126d8b 4146- variable substitution using "... ${name} ..." syntax
2729af9d
WD
4147- special characters ('$', ';') can be escaped by prefixing with '\',
4148 for example:
fe126d8b 4149 setenv bootcmd bootm \${address}
2729af9d
WD
4150- You can also escape text by enclosing in single apostrophes, for example:
4151 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
c609719b 4152
2729af9d
WD
4153Hush shell:
4154-----------
c609719b 4155
2729af9d
WD
4156- similar to Bourne shell, with control structures like
4157 if...then...else...fi, for...do...done; while...do...done,
4158 until...do...done, ...
4159- supports environment ("global") variables (through setenv / saveenv
4160 commands) and local shell variables (through standard shell syntax
4161 "name=value"); only environment variables can be used with "run"
4162 command
4163
4164General rules:
4165--------------
c609719b 4166
2729af9d
WD
4167(1) If a command line (or an environment variable executed by a "run"
4168 command) contains several commands separated by semicolon, and
4169 one of these commands fails, then the remaining commands will be
4170 executed anyway.
c609719b 4171
2729af9d 4172(2) If you execute several variables with one call to run (i. e.
11ccc33f 4173 calling run with a list of variables as arguments), any failing
2729af9d
WD
4174 command will cause "run" to terminate, i. e. the remaining
4175 variables are not executed.
c609719b 4176
2729af9d
WD
4177Note for Redundant Ethernet Interfaces:
4178=======================================
c609719b 4179
11ccc33f 4180Some boards come with redundant Ethernet interfaces; U-Boot supports
2729af9d
WD
4181such configurations and is capable of automatic selection of a
4182"working" interface when needed. MAC assignment works as follows:
c609719b 4183
2729af9d
WD
4184Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4185MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4186"eth1addr" (=>eth1), "eth2addr", ...
c609719b 4187
2729af9d
WD
4188If the network interface stores some valid MAC address (for instance
4189in SROM), this is used as default address if there is NO correspon-
4190ding setting in the environment; if the corresponding environment
4191variable is set, this overrides the settings in the card; that means:
c609719b 4192
2729af9d
WD
4193o If the SROM has a valid MAC address, and there is no address in the
4194 environment, the SROM's address is used.
c609719b 4195
2729af9d
WD
4196o If there is no valid address in the SROM, and a definition in the
4197 environment exists, then the value from the environment variable is
4198 used.
c609719b 4199
2729af9d
WD
4200o If both the SROM and the environment contain a MAC address, and
4201 both addresses are the same, this MAC address is used.
c609719b 4202
2729af9d
WD
4203o If both the SROM and the environment contain a MAC address, and the
4204 addresses differ, the value from the environment is used and a
4205 warning is printed.
c609719b 4206
2729af9d 4207o If neither SROM nor the environment contain a MAC address, an error
bef1014b
JH
4208 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
4209 a random, locally-assigned MAC is used.
c609719b 4210
ecee9324 4211If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
c0f40859 4212will be programmed into hardware as part of the initialization process. This
ecee9324
BW
4213may be skipped by setting the appropriate 'ethmacskip' environment variable.
4214The naming convention is as follows:
4215"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
c609719b 4216
2729af9d
WD
4217Image Formats:
4218==============
c609719b 4219
3310c549
MB
4220U-Boot is capable of booting (and performing other auxiliary operations on)
4221images in two formats:
4222
4223New uImage format (FIT)
4224-----------------------
4225
4226Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4227to Flattened Device Tree). It allows the use of images with multiple
4228components (several kernels, ramdisks, etc.), with contents protected by
4229SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4230
4231
4232Old uImage format
4233-----------------
4234
4235Old image format is based on binary files which can be basically anything,
4236preceded by a special header; see the definitions in include/image.h for
4237details; basically, the header defines the following image properties:
c609719b 4238
2729af9d
WD
4239* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4240 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
f5ed9e39
PT
4241 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4242 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4243 INTEGRITY).
daab59ac 4244* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
afc1ce82 4245 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
daab59ac 4246 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
2729af9d
WD
4247* Compression Type (uncompressed, gzip, bzip2)
4248* Load Address
4249* Entry Point
4250* Image Name
4251* Image Timestamp
c609719b 4252
2729af9d
WD
4253The header is marked by a special Magic Number, and both the header
4254and the data portions of the image are secured against corruption by
4255CRC32 checksums.
c609719b
WD
4256
4257
2729af9d
WD
4258Linux Support:
4259==============
c609719b 4260
2729af9d
WD
4261Although U-Boot should support any OS or standalone application
4262easily, the main focus has always been on Linux during the design of
4263U-Boot.
c609719b 4264
2729af9d
WD
4265U-Boot includes many features that so far have been part of some
4266special "boot loader" code within the Linux kernel. Also, any
4267"initrd" images to be used are no longer part of one big Linux image;
4268instead, kernel and "initrd" are separate images. This implementation
4269serves several purposes:
c609719b 4270
2729af9d
WD
4271- the same features can be used for other OS or standalone
4272 applications (for instance: using compressed images to reduce the
4273 Flash memory footprint)
c609719b 4274
2729af9d
WD
4275- it becomes much easier to port new Linux kernel versions because
4276 lots of low-level, hardware dependent stuff are done by U-Boot
c609719b 4277
2729af9d
WD
4278- the same Linux kernel image can now be used with different "initrd"
4279 images; of course this also means that different kernel images can
4280 be run with the same "initrd". This makes testing easier (you don't
4281 have to build a new "zImage.initrd" Linux image when you just
4282 change a file in your "initrd"). Also, a field-upgrade of the
4283 software is easier now.
c609719b 4284
c609719b 4285
2729af9d
WD
4286Linux HOWTO:
4287============
c609719b 4288
2729af9d
WD
4289Porting Linux to U-Boot based systems:
4290---------------------------------------
c609719b 4291
2729af9d
WD
4292U-Boot cannot save you from doing all the necessary modifications to
4293configure the Linux device drivers for use with your target hardware
4294(no, we don't intend to provide a full virtual machine interface to
4295Linux :-).
c609719b 4296
a47a12be 4297But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
24ee89b9 4298
2729af9d
WD
4299Just make sure your machine specific header file (for instance
4300include/asm-ppc/tqm8xx.h) includes the same definition of the Board
1dc30693
MH
4301Information structure as we define in include/asm-<arch>/u-boot.h,
4302and make sure that your definition of IMAP_ADDR uses the same value
6d0f6bcf 4303as your U-Boot configuration in CONFIG_SYS_IMMR.
24ee89b9 4304
2eb31b13
SG
4305Note that U-Boot now has a driver model, a unified model for drivers.
4306If you are adding a new driver, plumb it into driver model. If there
4307is no uclass available, you are encouraged to create one. See
4308doc/driver-model.
4309
c609719b 4310
2729af9d
WD
4311Configuring the Linux kernel:
4312-----------------------------
c609719b 4313
2729af9d
WD
4314No specific requirements for U-Boot. Make sure you have some root
4315device (initial ramdisk, NFS) for your target system.
4316
4317
4318Building a Linux Image:
4319-----------------------
c609719b 4320
2729af9d
WD
4321With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4322not used. If you use recent kernel source, a new build target
4323"uImage" will exist which automatically builds an image usable by
4324U-Boot. Most older kernels also have support for a "pImage" target,
4325which was introduced for our predecessor project PPCBoot and uses a
4326100% compatible format.
4327
4328Example:
4329
ab584d67 4330 make TQM850L_defconfig
2729af9d
WD
4331 make oldconfig
4332 make dep
4333 make uImage
4334
4335The "uImage" build target uses a special tool (in 'tools/mkimage') to
4336encapsulate a compressed Linux kernel image with header information,
4337CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4338
4339* build a standard "vmlinux" kernel image (in ELF binary format):
4340
4341* convert the kernel into a raw binary image:
4342
4343 ${CROSS_COMPILE}-objcopy -O binary \
4344 -R .note -R .comment \
4345 -S vmlinux linux.bin
4346
4347* compress the binary image:
4348
4349 gzip -9 linux.bin
4350
4351* package compressed binary image for U-Boot:
4352
4353 mkimage -A ppc -O linux -T kernel -C gzip \
4354 -a 0 -e 0 -n "Linux Kernel Image" \
4355 -d linux.bin.gz uImage
c609719b 4356
c609719b 4357
2729af9d
WD
4358The "mkimage" tool can also be used to create ramdisk images for use
4359with U-Boot, either separated from the Linux kernel image, or
4360combined into one file. "mkimage" encapsulates the images with a 64
4361byte header containing information about target architecture,
4362operating system, image type, compression method, entry points, time
4363stamp, CRC32 checksums, etc.
4364
4365"mkimage" can be called in two ways: to verify existing images and
4366print the header information, or to build new images.
4367
4368In the first form (with "-l" option) mkimage lists the information
4369contained in the header of an existing U-Boot image; this includes
4370checksum verification:
c609719b 4371
2729af9d
WD
4372 tools/mkimage -l image
4373 -l ==> list image header information
4374
4375The second form (with "-d" option) is used to build a U-Boot image
4376from a "data file" which is used as image payload:
4377
4378 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4379 -n name -d data_file image
4380 -A ==> set architecture to 'arch'
4381 -O ==> set operating system to 'os'
4382 -T ==> set image type to 'type'
4383 -C ==> set compression type 'comp'
4384 -a ==> set load address to 'addr' (hex)
4385 -e ==> set entry point to 'ep' (hex)
4386 -n ==> set image name to 'name'
4387 -d ==> use image data from 'datafile'
4388
69459791
WD
4389Right now, all Linux kernels for PowerPC systems use the same load
4390address (0x00000000), but the entry point address depends on the
4391kernel version:
2729af9d
WD
4392
4393- 2.2.x kernels have the entry point at 0x0000000C,
4394- 2.3.x and later kernels have the entry point at 0x00000000.
4395
4396So a typical call to build a U-Boot image would read:
4397
4398 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4399 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
a47a12be 4400 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
2729af9d
WD
4401 > examples/uImage.TQM850L
4402 Image Name: 2.4.4 kernel for TQM850L
4403 Created: Wed Jul 19 02:34:59 2000
4404 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4405 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4406 Load Address: 0x00000000
4407 Entry Point: 0x00000000
4408
4409To verify the contents of the image (or check for corruption):
4410
4411 -> tools/mkimage -l examples/uImage.TQM850L
4412 Image Name: 2.4.4 kernel for TQM850L
4413 Created: Wed Jul 19 02:34:59 2000
4414 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4415 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4416 Load Address: 0x00000000
4417 Entry Point: 0x00000000
4418
4419NOTE: for embedded systems where boot time is critical you can trade
4420speed for memory and install an UNCOMPRESSED image instead: this
4421needs more space in Flash, but boots much faster since it does not
4422need to be uncompressed:
4423
a47a12be 4424 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
2729af9d
WD
4425 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4426 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
a47a12be 4427 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
2729af9d
WD
4428 > examples/uImage.TQM850L-uncompressed
4429 Image Name: 2.4.4 kernel for TQM850L
4430 Created: Wed Jul 19 02:34:59 2000
4431 Image Type: PowerPC Linux Kernel Image (uncompressed)
4432 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4433 Load Address: 0x00000000
4434 Entry Point: 0x00000000
4435
4436
4437Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4438when your kernel is intended to use an initial ramdisk:
4439
4440 -> tools/mkimage -n 'Simple Ramdisk Image' \
4441 > -A ppc -O linux -T ramdisk -C gzip \
4442 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4443 Image Name: Simple Ramdisk Image
4444 Created: Wed Jan 12 14:01:50 2000
4445 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4446 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4447 Load Address: 0x00000000
4448 Entry Point: 0x00000000
4449
a804b5ce
GMF
4450The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
4451option performs the converse operation of the mkimage's second form (the "-d"
4452option). Given an image built by mkimage, the dumpimage extracts a "data file"
4453from the image:
4454
f41f5b7c
GMF
4455 tools/dumpimage -i image -T type -p position data_file
4456 -i ==> extract from the 'image' a specific 'data_file'
4457 -T ==> set image type to 'type'
4458 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
a804b5ce 4459
2729af9d
WD
4460
4461Installing a Linux Image:
4462-------------------------
4463
4464To downloading a U-Boot image over the serial (console) interface,
4465you must convert the image to S-Record format:
4466
4467 objcopy -I binary -O srec examples/image examples/image.srec
4468
4469The 'objcopy' does not understand the information in the U-Boot
4470image header, so the resulting S-Record file will be relative to
4471address 0x00000000. To load it to a given address, you need to
4472specify the target address as 'offset' parameter with the 'loads'
4473command.
4474
4475Example: install the image to address 0x40100000 (which on the
4476TQM8xxL is in the first Flash bank):
4477
4478 => erase 40100000 401FFFFF
4479
4480 .......... done
4481 Erased 8 sectors
4482
4483 => loads 40100000
4484 ## Ready for S-Record download ...
4485 ~>examples/image.srec
4486 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4487 ...
4488 15989 15990 15991 15992
4489 [file transfer complete]
4490 [connected]
4491 ## Start Addr = 0x00000000
4492
4493
4494You can check the success of the download using the 'iminfo' command;
218ca724 4495this includes a checksum verification so you can be sure no data
2729af9d
WD
4496corruption happened:
4497
4498 => imi 40100000
4499
4500 ## Checking Image at 40100000 ...
4501 Image Name: 2.2.13 for initrd on TQM850L
4502 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4503 Data Size: 335725 Bytes = 327 kB = 0 MB
4504 Load Address: 00000000
4505 Entry Point: 0000000c
4506 Verifying Checksum ... OK
4507
4508
4509Boot Linux:
4510-----------
4511
4512The "bootm" command is used to boot an application that is stored in
4513memory (RAM or Flash). In case of a Linux kernel image, the contents
4514of the "bootargs" environment variable is passed to the kernel as
4515parameters. You can check and modify this variable using the
4516"printenv" and "setenv" commands:
4517
4518
4519 => printenv bootargs
4520 bootargs=root=/dev/ram
4521
4522 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4523
4524 => printenv bootargs
4525 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4526
4527 => bootm 40020000
4528 ## Booting Linux kernel at 40020000 ...
4529 Image Name: 2.2.13 for NFS on TQM850L
4530 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4531 Data Size: 381681 Bytes = 372 kB = 0 MB
4532 Load Address: 00000000
4533 Entry Point: 0000000c
4534 Verifying Checksum ... OK
4535 Uncompressing Kernel Image ... OK
4536 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
4537 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4538 time_init: decrementer frequency = 187500000/60
4539 Calibrating delay loop... 49.77 BogoMIPS
4540 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4541 ...
4542
11ccc33f 4543If you want to boot a Linux kernel with initial RAM disk, you pass
2729af9d
WD
4544the memory addresses of both the kernel and the initrd image (PPBCOOT
4545format!) to the "bootm" command:
4546
4547 => imi 40100000 40200000
4548
4549 ## Checking Image at 40100000 ...
4550 Image Name: 2.2.13 for initrd on TQM850L
4551 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4552 Data Size: 335725 Bytes = 327 kB = 0 MB
4553 Load Address: 00000000
4554 Entry Point: 0000000c
4555 Verifying Checksum ... OK
4556
4557 ## Checking Image at 40200000 ...
4558 Image Name: Simple Ramdisk Image
4559 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4560 Data Size: 566530 Bytes = 553 kB = 0 MB
4561 Load Address: 00000000
4562 Entry Point: 00000000
4563 Verifying Checksum ... OK
4564
4565 => bootm 40100000 40200000
4566 ## Booting Linux kernel at 40100000 ...
4567 Image Name: 2.2.13 for initrd on TQM850L
4568 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4569 Data Size: 335725 Bytes = 327 kB = 0 MB
4570 Load Address: 00000000
4571 Entry Point: 0000000c
4572 Verifying Checksum ... OK
4573 Uncompressing Kernel Image ... OK
4574 ## Loading RAMDisk Image at 40200000 ...
4575 Image Name: Simple Ramdisk Image
4576 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4577 Data Size: 566530 Bytes = 553 kB = 0 MB
4578 Load Address: 00000000
4579 Entry Point: 00000000
4580 Verifying Checksum ... OK
4581 Loading Ramdisk ... OK
4582 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
4583 Boot arguments: root=/dev/ram
4584 time_init: decrementer frequency = 187500000/60
4585 Calibrating delay loop... 49.77 BogoMIPS
4586 ...
4587 RAMDISK: Compressed image found at block 0
4588 VFS: Mounted root (ext2 filesystem).
4589
4590 bash#
4591
0267768e
MM
4592Boot Linux and pass a flat device tree:
4593-----------
4594
4595First, U-Boot must be compiled with the appropriate defines. See the section
4596titled "Linux Kernel Interface" above for a more in depth explanation. The
4597following is an example of how to start a kernel and pass an updated
4598flat device tree:
4599
4600=> print oftaddr
4601oftaddr=0x300000
4602=> print oft
4603oft=oftrees/mpc8540ads.dtb
4604=> tftp $oftaddr $oft
4605Speed: 1000, full duplex
4606Using TSEC0 device
4607TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4608Filename 'oftrees/mpc8540ads.dtb'.
4609Load address: 0x300000
4610Loading: #
4611done
4612Bytes transferred = 4106 (100a hex)
4613=> tftp $loadaddr $bootfile
4614Speed: 1000, full duplex
4615Using TSEC0 device
4616TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4617Filename 'uImage'.
4618Load address: 0x200000
4619Loading:############
4620done
4621Bytes transferred = 1029407 (fb51f hex)
4622=> print loadaddr
4623loadaddr=200000
4624=> print oftaddr
4625oftaddr=0x300000
4626=> bootm $loadaddr - $oftaddr
4627## Booting image at 00200000 ...
a9398e01
WD
4628 Image Name: Linux-2.6.17-dirty
4629 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4630 Data Size: 1029343 Bytes = 1005.2 kB
0267768e 4631 Load Address: 00000000
a9398e01 4632 Entry Point: 00000000
0267768e
MM
4633 Verifying Checksum ... OK
4634 Uncompressing Kernel Image ... OK
4635Booting using flat device tree at 0x300000
4636Using MPC85xx ADS machine description
4637Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4638[snip]
4639
4640
2729af9d
WD
4641More About U-Boot Image Types:
4642------------------------------
4643
4644U-Boot supports the following image types:
4645
4646 "Standalone Programs" are directly runnable in the environment
4647 provided by U-Boot; it is expected that (if they behave
4648 well) you can continue to work in U-Boot after return from
4649 the Standalone Program.
4650 "OS Kernel Images" are usually images of some Embedded OS which
4651 will take over control completely. Usually these programs
4652 will install their own set of exception handlers, device
4653 drivers, set up the MMU, etc. - this means, that you cannot
4654 expect to re-enter U-Boot except by resetting the CPU.
4655 "RAMDisk Images" are more or less just data blocks, and their
4656 parameters (address, size) are passed to an OS kernel that is
4657 being started.
4658 "Multi-File Images" contain several images, typically an OS
4659 (Linux) kernel image and one or more data images like
4660 RAMDisks. This construct is useful for instance when you want
4661 to boot over the network using BOOTP etc., where the boot
4662 server provides just a single image file, but you want to get
4663 for instance an OS kernel and a RAMDisk image.
4664
4665 "Multi-File Images" start with a list of image sizes, each
4666 image size (in bytes) specified by an "uint32_t" in network
4667 byte order. This list is terminated by an "(uint32_t)0".
4668 Immediately after the terminating 0 follow the images, one by
4669 one, all aligned on "uint32_t" boundaries (size rounded up to
4670 a multiple of 4 bytes).
4671
4672 "Firmware Images" are binary images containing firmware (like
4673 U-Boot or FPGA images) which usually will be programmed to
4674 flash memory.
4675
4676 "Script files" are command sequences that will be executed by
4677 U-Boot's command interpreter; this feature is especially
4678 useful when you configure U-Boot to use a real shell (hush)
4679 as command interpreter.
4680
44f074c7
MV
4681Booting the Linux zImage:
4682-------------------------
4683
4684On some platforms, it's possible to boot Linux zImage. This is done
4685using the "bootz" command. The syntax of "bootz" command is the same
4686as the syntax of "bootm" command.
4687
8ac28563 4688Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
017e1f3f
MV
4689kernel with raw initrd images. The syntax is slightly different, the
4690address of the initrd must be augmented by it's size, in the following
4691format: "<initrd addres>:<initrd size>".
4692
2729af9d
WD
4693
4694Standalone HOWTO:
4695=================
4696
4697One of the features of U-Boot is that you can dynamically load and
4698run "standalone" applications, which can use some resources of
4699U-Boot like console I/O functions or interrupt services.
4700
4701Two simple examples are included with the sources:
4702
4703"Hello World" Demo:
4704-------------------
4705
4706'examples/hello_world.c' contains a small "Hello World" Demo
4707application; it is automatically compiled when you build U-Boot.
4708It's configured to run at address 0x00040004, so you can play with it
4709like that:
4710
4711 => loads
4712 ## Ready for S-Record download ...
4713 ~>examples/hello_world.srec
4714 1 2 3 4 5 6 7 8 9 10 11 ...
4715 [file transfer complete]
4716 [connected]
4717 ## Start Addr = 0x00040004
4718
4719 => go 40004 Hello World! This is a test.
4720 ## Starting application at 0x00040004 ...
4721 Hello World
4722 argc = 7
4723 argv[0] = "40004"
4724 argv[1] = "Hello"
4725 argv[2] = "World!"
4726 argv[3] = "This"
4727 argv[4] = "is"
4728 argv[5] = "a"
4729 argv[6] = "test."
4730 argv[7] = "<NULL>"
4731 Hit any key to exit ...
4732
4733 ## Application terminated, rc = 0x0
4734
4735Another example, which demonstrates how to register a CPM interrupt
4736handler with the U-Boot code, can be found in 'examples/timer.c'.
4737Here, a CPM timer is set up to generate an interrupt every second.
4738The interrupt service routine is trivial, just printing a '.'
4739character, but this is just a demo program. The application can be
4740controlled by the following keys:
4741
4742 ? - print current values og the CPM Timer registers
4743 b - enable interrupts and start timer
4744 e - stop timer and disable interrupts
4745 q - quit application
4746
4747 => loads
4748 ## Ready for S-Record download ...
4749 ~>examples/timer.srec
4750 1 2 3 4 5 6 7 8 9 10 11 ...
4751 [file transfer complete]
4752 [connected]
4753 ## Start Addr = 0x00040004
4754
4755 => go 40004
4756 ## Starting application at 0x00040004 ...
4757 TIMERS=0xfff00980
4758 Using timer 1
4759 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4760
4761Hit 'b':
4762 [q, b, e, ?] Set interval 1000000 us
4763 Enabling timer
4764Hit '?':
4765 [q, b, e, ?] ........
4766 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4767Hit '?':
4768 [q, b, e, ?] .
4769 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4770Hit '?':
4771 [q, b, e, ?] .
4772 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4773Hit '?':
4774 [q, b, e, ?] .
4775 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4776Hit 'e':
4777 [q, b, e, ?] ...Stopping timer
4778Hit 'q':
4779 [q, b, e, ?] ## Application terminated, rc = 0x0
4780
4781
4782Minicom warning:
4783================
4784
4785Over time, many people have reported problems when trying to use the
4786"minicom" terminal emulation program for serial download. I (wd)
4787consider minicom to be broken, and recommend not to use it. Under
4788Unix, I recommend to use C-Kermit for general purpose use (and
4789especially for kermit binary protocol download ("loadb" command), and
e53515a2
KP
4790use "cu" for S-Record download ("loads" command). See
4791http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4792for help with kermit.
4793
2729af9d
WD
4794
4795Nevertheless, if you absolutely want to use it try adding this
4796configuration to your "File transfer protocols" section:
4797
4798 Name Program Name U/D FullScr IO-Red. Multi
4799 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4800 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4801
4802
4803NetBSD Notes:
4804=============
4805
4806Starting at version 0.9.2, U-Boot supports NetBSD both as host
4807(build U-Boot) and target system (boots NetBSD/mpc8xx).
4808
4809Building requires a cross environment; it is known to work on
4810NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4811need gmake since the Makefiles are not compatible with BSD make).
4812Note that the cross-powerpc package does not install include files;
4813attempting to build U-Boot will fail because <machine/ansi.h> is
4814missing. This file has to be installed and patched manually:
4815
4816 # cd /usr/pkg/cross/powerpc-netbsd/include
4817 # mkdir powerpc
4818 # ln -s powerpc machine
4819 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4820 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4821
4822Native builds *don't* work due to incompatibilities between native
4823and U-Boot include files.
4824
4825Booting assumes that (the first part of) the image booted is a
4826stage-2 loader which in turn loads and then invokes the kernel
4827proper. Loader sources will eventually appear in the NetBSD source
4828tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2a8af187 4829meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
2729af9d
WD
4830
4831
4832Implementation Internals:
4833=========================
4834
4835The following is not intended to be a complete description of every
4836implementation detail. However, it should help to understand the
4837inner workings of U-Boot and make it easier to port it to custom
4838hardware.
4839
4840
4841Initial Stack, Global Data:
4842---------------------------
4843
4844The implementation of U-Boot is complicated by the fact that U-Boot
4845starts running out of ROM (flash memory), usually without access to
4846system RAM (because the memory controller is not initialized yet).
4847This means that we don't have writable Data or BSS segments, and BSS
4848is not initialized as zero. To be able to get a C environment working
4849at all, we have to allocate at least a minimal stack. Implementation
4850options for this are defined and restricted by the CPU used: Some CPU
4851models provide on-chip memory (like the IMMR area on MPC8xx and
4852MPC826x processors), on others (parts of) the data cache can be
4853locked as (mis-) used as memory, etc.
4854
218ca724 4855 Chris Hallinan posted a good summary of these issues to the
0668236b 4856 U-Boot mailing list:
2729af9d
WD
4857
4858 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4859 From: "Chris Hallinan" <clh@net1plus.com>
4860 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4861 ...
4862
4863 Correct me if I'm wrong, folks, but the way I understand it
4864 is this: Using DCACHE as initial RAM for Stack, etc, does not
4865 require any physical RAM backing up the cache. The cleverness
4866 is that the cache is being used as a temporary supply of
4867 necessary storage before the SDRAM controller is setup. It's
11ccc33f 4868 beyond the scope of this list to explain the details, but you
2729af9d
WD
4869 can see how this works by studying the cache architecture and
4870 operation in the architecture and processor-specific manuals.
4871
4872 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4873 is another option for the system designer to use as an
11ccc33f 4874 initial stack/RAM area prior to SDRAM being available. Either
2729af9d
WD
4875 option should work for you. Using CS 4 should be fine if your
4876 board designers haven't used it for something that would
4877 cause you grief during the initial boot! It is frequently not
4878 used.
4879
6d0f6bcf 4880 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
2729af9d
WD
4881 with your processor/board/system design. The default value
4882 you will find in any recent u-boot distribution in
8a316c9b 4883 walnut.h should work for you. I'd set it to a value larger
2729af9d
WD
4884 than your SDRAM module. If you have a 64MB SDRAM module, set
4885 it above 400_0000. Just make sure your board has no resources
4886 that are supposed to respond to that address! That code in
4887 start.S has been around a while and should work as is when
4888 you get the config right.
4889
4890 -Chris Hallinan
4891 DS4.COM, Inc.
4892
4893It is essential to remember this, since it has some impact on the C
4894code for the initialization procedures:
4895
4896* Initialized global data (data segment) is read-only. Do not attempt
4897 to write it.
4898
b445bbb4 4899* Do not use any uninitialized global data (or implicitly initialized
2729af9d
WD
4900 as zero data - BSS segment) at all - this is undefined, initiali-
4901 zation is performed later (when relocating to RAM).
4902
4903* Stack space is very limited. Avoid big data buffers or things like
4904 that.
4905
4906Having only the stack as writable memory limits means we cannot use
b445bbb4 4907normal global data to share information between the code. But it
2729af9d
WD
4908turned out that the implementation of U-Boot can be greatly
4909simplified by making a global data structure (gd_t) available to all
4910functions. We could pass a pointer to this data as argument to _all_
4911functions, but this would bloat the code. Instead we use a feature of
4912the GCC compiler (Global Register Variables) to share the data: we
4913place a pointer (gd) to the global data into a register which we
4914reserve for this purpose.
4915
4916When choosing a register for such a purpose we are restricted by the
4917relevant (E)ABI specifications for the current architecture, and by
4918GCC's implementation.
4919
4920For PowerPC, the following registers have specific use:
4921 R1: stack pointer
e7670f6c 4922 R2: reserved for system use
2729af9d
WD
4923 R3-R4: parameter passing and return values
4924 R5-R10: parameter passing
4925 R13: small data area pointer
4926 R30: GOT pointer
4927 R31: frame pointer
4928
e6bee808
JT
4929 (U-Boot also uses R12 as internal GOT pointer. r12
4930 is a volatile register so r12 needs to be reset when
4931 going back and forth between asm and C)
2729af9d 4932
e7670f6c 4933 ==> U-Boot will use R2 to hold a pointer to the global data
2729af9d
WD
4934
4935 Note: on PPC, we could use a static initializer (since the
4936 address of the global data structure is known at compile time),
4937 but it turned out that reserving a register results in somewhat
4938 smaller code - although the code savings are not that big (on
4939 average for all boards 752 bytes for the whole U-Boot image,
4940 624 text + 127 data).
4941
4942On ARM, the following registers are used:
4943
4944 R0: function argument word/integer result
4945 R1-R3: function argument word
12eba1b4
JH
4946 R9: platform specific
4947 R10: stack limit (used only if stack checking is enabled)
2729af9d
WD
4948 R11: argument (frame) pointer
4949 R12: temporary workspace
4950 R13: stack pointer
4951 R14: link register
4952 R15: program counter
4953
12eba1b4
JH
4954 ==> U-Boot will use R9 to hold a pointer to the global data
4955
4956 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
2729af9d 4957
0df01fd3
TC
4958On Nios II, the ABI is documented here:
4959 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4960
4961 ==> U-Boot will use gp to hold a pointer to the global data
4962
4963 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4964 to access small data sections, so gp is free.
4965
afc1ce82
ML
4966On NDS32, the following registers are used:
4967
4968 R0-R1: argument/return
4969 R2-R5: argument
4970 R15: temporary register for assembler
4971 R16: trampoline register
4972 R28: frame pointer (FP)
4973 R29: global pointer (GP)
4974 R30: link register (LP)
4975 R31: stack pointer (SP)
4976 PC: program counter (PC)
4977
4978 ==> U-Boot will use R10 to hold a pointer to the global data
4979
d87080b7
WD
4980NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4981or current versions of GCC may "optimize" the code too much.
2729af9d
WD
4982
4983Memory Management:
4984------------------
4985
4986U-Boot runs in system state and uses physical addresses, i.e. the
4987MMU is not used either for address mapping nor for memory protection.
4988
4989The available memory is mapped to fixed addresses using the memory
4990controller. In this process, a contiguous block is formed for each
4991memory type (Flash, SDRAM, SRAM), even when it consists of several
4992physical memory banks.
4993
4994U-Boot is installed in the first 128 kB of the first Flash bank (on
4995TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4996booting and sizing and initializing DRAM, the code relocates itself
4997to the upper end of DRAM. Immediately below the U-Boot code some
6d0f6bcf 4998memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
2729af9d
WD
4999configuration setting]. Below that, a structure with global Board
5000Info data is placed, followed by the stack (growing downward).
5001
5002Additionally, some exception handler code is copied to the low 8 kB
5003of DRAM (0x00000000 ... 0x00001FFF).
5004
5005So a typical memory configuration with 16 MB of DRAM could look like
5006this:
5007
5008 0x0000 0000 Exception Vector code
5009 :
5010 0x0000 1FFF
5011 0x0000 2000 Free for Application Use
5012 :
5013 :
5014
5015 :
5016 :
5017 0x00FB FF20 Monitor Stack (Growing downward)
5018 0x00FB FFAC Board Info Data and permanent copy of global data
5019 0x00FC 0000 Malloc Arena
5020 :
5021 0x00FD FFFF
5022 0x00FE 0000 RAM Copy of Monitor Code
5023 ... eventually: LCD or video framebuffer
5024 ... eventually: pRAM (Protected RAM - unchanged by reset)
5025 0x00FF FFFF [End of RAM]
5026
5027
5028System Initialization:
5029----------------------
c609719b 5030
2729af9d 5031In the reset configuration, U-Boot starts at the reset entry point
11ccc33f 5032(on most PowerPC systems at address 0x00000100). Because of the reset
b445bbb4 5033configuration for CS0# this is a mirror of the on board Flash memory.
2729af9d
WD
5034To be able to re-map memory U-Boot then jumps to its link address.
5035To be able to implement the initialization code in C, a (small!)
5036initial stack is set up in the internal Dual Ported RAM (in case CPUs
2eb48ff7
HS
5037which provide such a feature like), or in a locked part of the data
5038cache. After that, U-Boot initializes the CPU core, the caches and
5039the SIU.
2729af9d
WD
5040
5041Next, all (potentially) available memory banks are mapped using a
5042preliminary mapping. For example, we put them on 512 MB boundaries
5043(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5044on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5045programmed for SDRAM access. Using the temporary configuration, a
5046simple memory test is run that determines the size of the SDRAM
5047banks.
5048
5049When there is more than one SDRAM bank, and the banks are of
5050different size, the largest is mapped first. For equal size, the first
5051bank (CS2#) is mapped first. The first mapping is always for address
50520x00000000, with any additional banks following immediately to create
5053contiguous memory starting from 0.
5054
5055Then, the monitor installs itself at the upper end of the SDRAM area
5056and allocates memory for use by malloc() and for the global Board
5057Info data; also, the exception vector code is copied to the low RAM
5058pages, and the final stack is set up.
5059
5060Only after this relocation will you have a "normal" C environment;
5061until that you are restricted in several ways, mostly because you are
5062running from ROM, and because the code will have to be relocated to a
5063new address in RAM.
5064
5065
5066U-Boot Porting Guide:
5067----------------------
c609719b 5068
2729af9d
WD
5069[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5070list, October 2002]
c609719b
WD
5071
5072
6c3fef28 5073int main(int argc, char *argv[])
2729af9d
WD
5074{
5075 sighandler_t no_more_time;
c609719b 5076
6c3fef28
JVB
5077 signal(SIGALRM, no_more_time);
5078 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
c609719b 5079
2729af9d 5080 if (available_money > available_manpower) {
6c3fef28 5081 Pay consultant to port U-Boot;
c609719b
WD
5082 return 0;
5083 }
5084
2729af9d
WD
5085 Download latest U-Boot source;
5086
0668236b 5087 Subscribe to u-boot mailing list;
2729af9d 5088
6c3fef28
JVB
5089 if (clueless)
5090 email("Hi, I am new to U-Boot, how do I get started?");
2729af9d
WD
5091
5092 while (learning) {
5093 Read the README file in the top level directory;
6c3fef28
JVB
5094 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5095 Read applicable doc/*.README;
2729af9d 5096 Read the source, Luke;
6c3fef28 5097 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
2729af9d
WD
5098 }
5099
6c3fef28
JVB
5100 if (available_money > toLocalCurrency ($2500))
5101 Buy a BDI3000;
5102 else
2729af9d 5103 Add a lot of aggravation and time;
2729af9d 5104
6c3fef28
JVB
5105 if (a similar board exists) { /* hopefully... */
5106 cp -a board/<similar> board/<myboard>
5107 cp include/configs/<similar>.h include/configs/<myboard>.h
5108 } else {
5109 Create your own board support subdirectory;
5110 Create your own board include/configs/<myboard>.h file;
5111 }
5112 Edit new board/<myboard> files
5113 Edit new include/configs/<myboard>.h
5114
5115 while (!accepted) {
5116 while (!running) {
5117 do {
5118 Add / modify source code;
5119 } until (compiles);
5120 Debug;
5121 if (clueless)
5122 email("Hi, I am having problems...");
5123 }
5124 Send patch file to the U-Boot email list;
5125 if (reasonable critiques)
5126 Incorporate improvements from email list code review;
5127 else
5128 Defend code as written;
2729af9d 5129 }
2729af9d
WD
5130
5131 return 0;
5132}
5133
5134void no_more_time (int sig)
5135{
5136 hire_a_guru();
5137}
5138
c609719b 5139
2729af9d
WD
5140Coding Standards:
5141-----------------
c609719b 5142
2729af9d 5143All contributions to U-Boot should conform to the Linux kernel
2c051651 5144coding style; see the file "Documentation/CodingStyle" and the script
7ca9296e 5145"scripts/Lindent" in your Linux kernel source directory.
2c051651
DZ
5146
5147Source files originating from a different project (for example the
5148MTD subsystem) are generally exempt from these guidelines and are not
b445bbb4 5149reformatted to ease subsequent migration to newer versions of those
2c051651
DZ
5150sources.
5151
5152Please note that U-Boot is implemented in C (and to some small parts in
5153Assembler); no C++ is used, so please do not use C++ style comments (//)
5154in your code.
c609719b 5155
2729af9d
WD
5156Please also stick to the following formatting rules:
5157- remove any trailing white space
7ca9296e 5158- use TAB characters for indentation and vertical alignment, not spaces
2729af9d 5159- make sure NOT to use DOS '\r\n' line feeds
7ca9296e 5160- do not add more than 2 consecutive empty lines to source files
2729af9d 5161- do not add trailing empty lines to source files
180d3f74 5162
2729af9d
WD
5163Submissions which do not conform to the standards may be returned
5164with a request to reformat the changes.
c609719b
WD
5165
5166
2729af9d
WD
5167Submitting Patches:
5168-------------------
c609719b 5169
2729af9d
WD
5170Since the number of patches for U-Boot is growing, we need to
5171establish some rules. Submissions which do not conform to these rules
5172may be rejected, even when they contain important and valuable stuff.
c609719b 5173
0d28f34b 5174Please see http://www.denx.de/wiki/U-Boot/Patches for details.
218ca724 5175
0668236b
WD
5176Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5177see http://lists.denx.de/mailman/listinfo/u-boot
5178
2729af9d
WD
5179When you send a patch, please include the following information with
5180it:
c609719b 5181
2729af9d
WD
5182* For bug fixes: a description of the bug and how your patch fixes
5183 this bug. Please try to include a way of demonstrating that the
5184 patch actually fixes something.
c609719b 5185
2729af9d
WD
5186* For new features: a description of the feature and your
5187 implementation.
c609719b 5188
2729af9d 5189* A CHANGELOG entry as plaintext (separate from the patch)
c609719b 5190
7207b366
RD
5191* For major contributions, add a MAINTAINERS file with your
5192 information and associated file and directory references.
c609719b 5193
27af930e
AA
5194* When you add support for a new board, don't forget to add a
5195 maintainer e-mail address to the boards.cfg file, too.
c609719b 5196
2729af9d
WD
5197* If your patch adds new configuration options, don't forget to
5198 document these in the README file.
c609719b 5199
218ca724
WD
5200* The patch itself. If you are using git (which is *strongly*
5201 recommended) you can easily generate the patch using the
7ca9296e 5202 "git format-patch". If you then use "git send-email" to send it to
218ca724
WD
5203 the U-Boot mailing list, you will avoid most of the common problems
5204 with some other mail clients.
5205
5206 If you cannot use git, use "diff -purN OLD NEW". If your version of
5207 diff does not support these options, then get the latest version of
5208 GNU diff.
c609719b 5209
218ca724
WD
5210 The current directory when running this command shall be the parent
5211 directory of the U-Boot source tree (i. e. please make sure that
5212 your patch includes sufficient directory information for the
5213 affected files).
6dff5529 5214
218ca724
WD
5215 We prefer patches as plain text. MIME attachments are discouraged,
5216 and compressed attachments must not be used.
c609719b 5217
2729af9d
WD
5218* If one logical set of modifications affects or creates several
5219 files, all these changes shall be submitted in a SINGLE patch file.
52f52c14 5220
2729af9d
WD
5221* Changesets that contain different, unrelated modifications shall be
5222 submitted as SEPARATE patches, one patch per changeset.
8bde7f77 5223
52f52c14 5224
2729af9d 5225Notes:
c609719b 5226
6de80f21 5227* Before sending the patch, run the buildman script on your patched
2729af9d
WD
5228 source tree and make sure that no errors or warnings are reported
5229 for any of the boards.
c609719b 5230
2729af9d
WD
5231* Keep your modifications to the necessary minimum: A patch
5232 containing several unrelated changes or arbitrary reformats will be
5233 returned with a request to re-formatting / split it.
c609719b 5234
2729af9d
WD
5235* If you modify existing code, make sure that your new code does not
5236 add to the memory footprint of the code ;-) Small is beautiful!
5237 When adding new features, these should compile conditionally only
5238 (using #ifdef), and the resulting code with the new feature
5239 disabled must not need more memory than the old code without your
5240 modification.
90dc6704 5241
0668236b
WD
5242* Remember that there is a size limit of 100 kB per message on the
5243 u-boot mailing list. Bigger patches will be moderated. If they are
5244 reasonable and not too big, they will be acknowledged. But patches
5245 bigger than the size limit should be avoided.