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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
315
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316The following options need to be configured:
317
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318- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
319
320- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
6ccec449 321
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322- Marvell Family Member
323 CONFIG_SYS_MVFS - define it if you want to enable
324 multiple fs option at one time
325 for marvell soc family
326
66412c63 327- 85xx CPU Options:
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328 CONFIG_SYS_PPC64
329
330 Specifies that the core is a 64-bit PowerPC implementation (implements
331 the "64" category of the Power ISA). This is necessary for ePAPR
332 compliance, among other possible reasons.
333
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334 CONFIG_SYS_FSL_TBCLK_DIV
335
336 Defines the core time base clock divider ratio compared to the
337 system clock. On most PQ3 devices this is 8, on newer QorIQ
338 devices it can be 16 or 32. The ratio varies from SoC to Soc.
339
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340 CONFIG_SYS_FSL_PCIE_COMPAT
341
342 Defines the string to utilize when trying to match PCIe device
343 tree nodes for the given platform.
344
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345 CONFIG_SYS_FSL_ERRATUM_A004510
346
347 Enables a workaround for erratum A004510. If set,
348 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
349 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
350
351 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
352 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
353
354 Defines one or two SoC revisions (low 8 bits of SVR)
355 for which the A004510 workaround should be applied.
356
357 The rest of SVR is either not relevant to the decision
358 of whether the erratum is present (e.g. p2040 versus
359 p2041) or is implied by the build target, which controls
360 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
361
362 See Freescale App Note 4493 for more information about
363 this erratum.
364
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365 CONFIG_A003399_NOR_WORKAROUND
366 Enables a workaround for IFC erratum A003399. It is only
b445bbb4 367 required during NOR boot.
74fa22ed 368
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369 CONFIG_A008044_WORKAROUND
370 Enables a workaround for T1040/T1042 erratum A008044. It is only
b445bbb4 371 required during NAND boot and valid for Rev 1.0 SoC revision
9f074e67 372
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373 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
374
375 This is the value to write into CCSR offset 0x18600
376 according to the A004510 workaround.
377
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378 CONFIG_SYS_FSL_DSP_DDR_ADDR
379 This value denotes start offset of DDR memory which is
380 connected exclusively to the DSP cores.
381
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382 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
383 This value denotes start offset of M2 memory
384 which is directly connected to the DSP core.
385
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386 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
387 This value denotes start offset of M3 memory which is directly
388 connected to the DSP core.
389
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390 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
391 This value denotes start offset of DSP CCSR space.
392
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393 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
394 Single Source Clock is clocking mode present in some of FSL SoC's.
395 In this mode, a single differential clock is used to supply
396 clocks to the sysclock, ddrclock and usbclock.
397
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398 CONFIG_SYS_CPC_REINIT_F
399 This CONFIG is defined when the CPC is configured as SRAM at the
a187559e 400 time of U-Boot entry and is required to be re-initialized.
fb4a2409 401
aade2004 402 CONFIG_DEEP_SLEEP
b445bbb4 403 Indicates this SoC supports deep sleep feature. If deep sleep is
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404 supported, core will start to execute uboot when wakes up.
405
6cb461b4 406- Generic CPU options:
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407 CONFIG_SYS_GENERIC_GLOBAL_DATA
408 Defines global data is initialized in generic board board_init_f().
409 If this macro is defined, global data is created and cleared in
410 generic board board_init_f(). Without this macro, architecture/board
411 should initialize global data before calling board_init_f().
412
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413 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
414
415 Defines the endianess of the CPU. Implementation of those
416 values is arch specific.
417
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418 CONFIG_SYS_FSL_DDR
419 Freescale DDR driver in use. This type of DDR controller is
420 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
421 SoCs.
422
423 CONFIG_SYS_FSL_DDR_ADDR
424 Freescale DDR memory-mapped register base.
425
426 CONFIG_SYS_FSL_DDR_EMU
427 Specify emulator support for DDR. Some DDR features such as
428 deskew training are not available.
429
430 CONFIG_SYS_FSL_DDRC_GEN1
431 Freescale DDR1 controller.
432
433 CONFIG_SYS_FSL_DDRC_GEN2
434 Freescale DDR2 controller.
435
436 CONFIG_SYS_FSL_DDRC_GEN3
437 Freescale DDR3 controller.
438
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439 CONFIG_SYS_FSL_DDRC_GEN4
440 Freescale DDR4 controller.
441
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442 CONFIG_SYS_FSL_DDRC_ARM_GEN3
443 Freescale DDR3 controller for ARM-based SoCs.
444
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445 CONFIG_SYS_FSL_DDR1
446 Board config to use DDR1. It can be enabled for SoCs with
447 Freescale DDR1 or DDR2 controllers, depending on the board
448 implemetation.
449
450 CONFIG_SYS_FSL_DDR2
62a3b7dd 451 Board config to use DDR2. It can be enabled for SoCs with
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452 Freescale DDR2 or DDR3 controllers, depending on the board
453 implementation.
454
455 CONFIG_SYS_FSL_DDR3
456 Board config to use DDR3. It can be enabled for SoCs with
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457 Freescale DDR3 or DDR3L controllers.
458
459 CONFIG_SYS_FSL_DDR3L
460 Board config to use DDR3L. It can be enabled for SoCs with
461 DDR3L controllers.
462
463 CONFIG_SYS_FSL_DDR4
464 Board config to use DDR4. It can be enabled for SoCs with
465 DDR4 controllers.
5614e71b 466
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467 CONFIG_SYS_FSL_IFC_BE
468 Defines the IFC controller register space as Big Endian
469
470 CONFIG_SYS_FSL_IFC_LE
471 Defines the IFC controller register space as Little Endian
472
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473 CONFIG_SYS_FSL_IFC_CLK_DIV
474 Defines divider of platform clock(clock input to IFC controller).
475
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476 CONFIG_SYS_FSL_LBC_CLK_DIV
477 Defines divider of platform clock(clock input to eLBC controller).
478
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479 CONFIG_SYS_FSL_PBL_PBI
480 It enables addition of RCW (Power on reset configuration) in built image.
481 Please refer doc/README.pblimage for more details
482
483 CONFIG_SYS_FSL_PBL_RCW
484 It adds PBI(pre-boot instructions) commands in u-boot build image.
485 PBI commands can be used to configure SoC before it starts the execution.
486 Please refer doc/README.pblimage for more details
487
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488 CONFIG_SPL_FSL_PBL
489 It adds a target to create boot binary having SPL binary in PBI format
490 concatenated with u-boot binary.
491
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492 CONFIG_SYS_FSL_DDR_BE
493 Defines the DDR controller register space as Big Endian
494
495 CONFIG_SYS_FSL_DDR_LE
496 Defines the DDR controller register space as Little Endian
497
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498 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
499 Physical address from the view of DDR controllers. It is the
500 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
501 it could be different for ARM SoCs.
502
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503 CONFIG_SYS_FSL_DDR_INTLV_256B
504 DDR controller interleaving on 256-byte. This is a special
505 interleaving mode, handled by Dickens for Freescale layerscape
506 SoCs with ARM core.
507
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508 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
509 Number of controllers used as main memory.
510
511 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
512 Number of controllers used for other than main memory.
513
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514 CONFIG_SYS_FSL_HAS_DP_DDR
515 Defines the SoC has DP-DDR used for DPAA.
516
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517 CONFIG_SYS_FSL_SEC_BE
518 Defines the SEC controller register space as Big Endian
519
520 CONFIG_SYS_FSL_SEC_LE
521 Defines the SEC controller register space as Little Endian
522
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523- MIPS CPU options:
524 CONFIG_SYS_INIT_SP_OFFSET
525
526 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
527 pointer. This is needed for the temporary stack before
528 relocation.
529
530 CONFIG_SYS_MIPS_CACHE_MODE
531
532 Cache operation mode for the MIPS CPU.
533 See also arch/mips/include/asm/mipsregs.h.
534 Possible values are:
535 CONF_CM_CACHABLE_NO_WA
536 CONF_CM_CACHABLE_WA
537 CONF_CM_UNCACHED
538 CONF_CM_CACHABLE_NONCOHERENT
539 CONF_CM_CACHABLE_CE
540 CONF_CM_CACHABLE_COW
541 CONF_CM_CACHABLE_CUW
542 CONF_CM_CACHABLE_ACCELERATED
543
544 CONFIG_SYS_XWAY_EBU_BOOTCFG
545
546 Special option for Lantiq XWAY SoCs for booting from NOR flash.
547 See also arch/mips/cpu/mips32/start.S.
548
549 CONFIG_XWAY_SWAP_BYTES
550
551 Enable compilation of tools/xway-swap-bytes needed for Lantiq
552 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
553 be swapped if a flash programmer is used.
554
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555- ARM options:
556 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
557
558 Select high exception vectors of the ARM core, e.g., do not
559 clear the V bit of the c1 register of CP15.
560
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561 COUNTER_FREQUENCY
562 Generic timer clock source frequency.
563
564 COUNTER_FREQUENCY_REAL
565 Generic timer clock source frequency if the real clock is
566 different from COUNTER_FREQUENCY, and can only be determined
567 at run time.
568
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569- Tegra SoC options:
570 CONFIG_TEGRA_SUPPORT_NON_SECURE
571
572 Support executing U-Boot in non-secure (NS) mode. Certain
573 impossible actions will be skipped if the CPU is in NS mode,
574 such as ARM architectural timer initialization.
575
5da627a4 576- Linux Kernel Interface:
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577 CONFIG_CLOCKS_IN_MHZ
578
579 U-Boot stores all clock information in Hz
580 internally. For binary compatibility with older Linux
581 kernels (which expect the clocks passed in the
582 bd_info data to be in MHz) the environment variable
583 "clocks_in_mhz" can be defined so that U-Boot
584 converts clock data to MHZ before passing it to the
585 Linux kernel.
c609719b 586 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
218ca724 587 "clocks_in_mhz=1" is automatically included in the
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588 default environment.
589
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590 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
591
b445bbb4 592 When transferring memsize parameter to Linux, some versions
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593 expect it to be in bytes, others in MB.
594 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
595
fec6d9ee 596 CONFIG_OF_LIBFDT
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597
598 New kernel versions are expecting firmware settings to be
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599 passed using flattened device trees (based on open firmware
600 concepts).
601
602 CONFIG_OF_LIBFDT
603 * New libfdt-based support
604 * Adds the "fdt" command
3bb342fc 605 * The bootm command automatically updates the fdt
213bf8c8 606
f57f70aa 607 OF_TBCLK - The timebase frequency.
c2871f03 608 OF_STDOUT_PATH - The path to the console device
f57f70aa 609
11ccc33f
MZ
610 boards with QUICC Engines require OF_QE to set UCC MAC
611 addresses
3bb342fc 612
4e253137
KG
613 CONFIG_OF_BOARD_SETUP
614
615 Board code has addition modification that it wants to make
616 to the flat device tree before handing it off to the kernel
f57f70aa 617
c654b517
SG
618 CONFIG_OF_SYSTEM_SETUP
619
620 Other code has addition modification that it wants to make
621 to the flat device tree before handing it off to the kernel.
622 This causes ft_system_setup() to be called before booting
623 the kernel.
624
3887c3fb
HS
625 CONFIG_OF_IDE_FIXUP
626
627 U-Boot can detect if an IDE device is present or not.
628 If not, and this new config option is activated, U-Boot
629 removes the ATA node from the DTS before booting Linux,
630 so the Linux IDE driver does not probe the device and
631 crash. This is needed for buggy hardware (uc101) where
632 no pull down resistor is connected to the signal IDE5V_DD7.
633
7eb29398
IG
634 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
635
636 This setting is mandatory for all boards that have only one
637 machine type and must be used to specify the machine type
638 number as it appears in the ARM machine registry
639 (see http://www.arm.linux.org.uk/developer/machines/).
640 Only boards that have multiple machine types supported
641 in a single configuration file and the machine type is
642 runtime discoverable, do not have to use this setting.
643
0b2f4eca
NG
644- vxWorks boot parameters:
645
646 bootvx constructs a valid bootline using the following
9e98b7e3
BM
647 environments variables: bootdev, bootfile, ipaddr, netmask,
648 serverip, gatewayip, hostname, othbootargs.
0b2f4eca
NG
649 It loads the vxWorks image pointed bootfile.
650
0b2f4eca
NG
651 Note: If a "bootargs" environment is defined, it will overwride
652 the defaults discussed just above.
653
2c451f78
A
654- Cache Configuration:
655 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
656 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
657 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
658
93bc2193
A
659- Cache Configuration for ARM:
660 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
661 controller
662 CONFIG_SYS_PL310_BASE - Physical base address of PL310
663 controller register space
664
6705d81e 665- Serial Ports:
48d0192f 666 CONFIG_PL010_SERIAL
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WD
667
668 Define this if you want support for Amba PrimeCell PL010 UARTs.
669
48d0192f 670 CONFIG_PL011_SERIAL
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671
672 Define this if you want support for Amba PrimeCell PL011 UARTs.
673
674 CONFIG_PL011_CLOCK
675
676 If you have Amba PrimeCell PL011 UARTs, set this variable to
677 the clock speed of the UARTs.
678
679 CONFIG_PL01x_PORTS
680
681 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
682 define this to a list of base addresses for each (supported)
683 port. See e.g. include/configs/versatile.h
684
d57dee57
KM
685 CONFIG_SERIAL_HW_FLOW_CONTROL
686
687 Define this variable to enable hw flow control in serial driver.
688 Current user of this option is drivers/serial/nsl16550.c driver
6705d81e 689
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690- Console Baudrate:
691 CONFIG_BAUDRATE - in bps
692 Select one of the baudrates listed in
6d0f6bcf 693 CONFIG_SYS_BAUDRATE_TABLE, see below.
c609719b 694
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695- Autoboot Command:
696 CONFIG_BOOTCOMMAND
697 Only needed when CONFIG_BOOTDELAY is enabled;
698 define a command string that is automatically executed
699 when no character is read on the console interface
700 within "Boot Delay" after reset.
701
702 CONFIG_BOOTARGS
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WD
703 This can be used to pass arguments to the bootm
704 command. The value of CONFIG_BOOTARGS goes into the
705 environment value "bootargs".
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706
707 CONFIG_RAMBOOT and CONFIG_NFSBOOT
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708 The value of these goes into the environment as
709 "ramboot" and "nfsboot" respectively, and can be used
710 as a convenience, when switching between booting from
11ccc33f 711 RAM and NFS.
c609719b 712
eda0ba38
HS
713- Bootcount:
714 CONFIG_BOOTCOUNT_LIMIT
715 Implements a mechanism for detecting a repeating reboot
716 cycle, see:
717 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
718
719 CONFIG_BOOTCOUNT_ENV
720 If no softreset save registers are found on the hardware
721 "bootcount" is stored in the environment. To prevent a
722 saveenv on all reboots, the environment variable
723 "upgrade_available" is used. If "upgrade_available" is
724 0, "bootcount" is always 0, if "upgrade_available" is
725 1 "bootcount" is incremented in the environment.
726 So the Userspace Applikation must set the "upgrade_available"
727 and "bootcount" variable to 0, if a boot was successfully.
728
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729- Pre-Boot Commands:
730 CONFIG_PREBOOT
731
732 When this option is #defined, the existence of the
733 environment variable "preboot" will be checked
734 immediately before starting the CONFIG_BOOTDELAY
735 countdown and/or running the auto-boot command resp.
736 entering interactive mode.
737
738 This feature is especially useful when "preboot" is
739 automatically generated or modified. For an example
740 see the LWMON board specific code: here "preboot" is
741 modified when the user holds down a certain
742 combination of keys on the (special) keyboard when
743 booting the systems
744
745- Serial Download Echo Mode:
746 CONFIG_LOADS_ECHO
747 If defined to 1, all characters received during a
748 serial download (using the "loads" command) are
749 echoed back. This might be needed by some terminal
750 emulations (like "cu"), but may as well just take
751 time on others. This setting #define's the initial
752 value of the "loads_echo" environment variable.
753
602ad3b3 754- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
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755 CONFIG_KGDB_BAUDRATE
756 Select one of the baudrates listed in
6d0f6bcf 757 CONFIG_SYS_BAUDRATE_TABLE, see below.
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758
759- Monitor Functions:
602ad3b3
JL
760 Monitor commands can be included or excluded
761 from the build by using the #include files
c6c621bd 762 <config_cmd_all.h> and #undef'ing unwanted
ef0f2f57 763 commands, or adding #define's for wanted commands.
602ad3b3
JL
764
765 The default command configuration includes all commands
766 except those marked below with a "*".
767
b401b73d 768 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
602ad3b3 769 CONFIG_CMD_ASKENV * ask for env variable
602ad3b3 770 CONFIG_CMD_BDI bdinfo
602ad3b3 771 CONFIG_CMD_BOOTD bootd
d2b2ffe3 772 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support
602ad3b3
JL
773 CONFIG_CMD_CACHE * icache, dcache
774 CONFIG_CMD_CONSOLE coninfo
602ad3b3
JL
775 CONFIG_CMD_DHCP * DHCP support
776 CONFIG_CMD_DIAG * Diagnostics
602ad3b3 777 CONFIG_CMD_ECHO echo arguments
246c6922 778 CONFIG_CMD_EDITENV edit env variable
602ad3b3 779 CONFIG_CMD_ELF * bootelf, bootvx
88733e2c 780 CONFIG_CMD_ENV_EXISTS * check existence of env variable
0c79cda0 781 CONFIG_CMD_EXPORTENV * export the environment
03e2ecf6
SW
782 CONFIG_CMD_EXT2 * ext2 command support
783 CONFIG_CMD_EXT4 * ext4 command support
16f4d933
SW
784 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
785 that work for multiple fs types
59e890ef 786 CONFIG_CMD_FS_UUID * Look up a filesystem UUID
bdab39d3 787 CONFIG_CMD_SAVEENV saveenv
602ad3b3
JL
788 CONFIG_CMD_FLASH flinfo, erase, protect
789 CONFIG_CMD_FPGA FPGA device initialization support
a641b979 790 CONFIG_CMD_GO * the 'go' command (exec code)
a000b795 791 CONFIG_CMD_GREPENV * search environment
602ad3b3 792 CONFIG_CMD_I2C * I2C serial bus support
602ad3b3 793 CONFIG_CMD_IMI iminfo
8fdf1e0f 794 CONFIG_CMD_IMLS List all images found in NOR flash
4d98b5c8 795 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
0c79cda0 796 CONFIG_CMD_IMPORTENV * import an environment
c167cc02 797 CONFIG_CMD_INI * import data from an ini file into the env
602ad3b3 798 CONFIG_CMD_ITEST Integer/string test of 2 values
4d98b5c8 799 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
d22c338e
JH
800 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
801 (169.254.*.*)
602ad3b3
JL
802 CONFIG_CMD_LOADB loadb
803 CONFIG_CMD_LOADS loads
4d98b5c8 804 CONFIG_CMD_MD5SUM * print md5 message digest
02c9aa1d 805 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
15a33e49 806 CONFIG_CMD_MEMINFO * Display detailed memory information
602ad3b3 807 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
a2681707 808 loop, loopw
4d98b5c8 809 CONFIG_CMD_MEMTEST * mtest
602ad3b3
JL
810 CONFIG_CMD_MISC Misc functions like sleep etc
811 CONFIG_CMD_MMC * MMC memory mapped support
812 CONFIG_CMD_MII * MII utility commands
602ad3b3 813 CONFIG_CMD_NET bootp, tftpboot, rarpboot
4d98b5c8 814 CONFIG_CMD_NFS NFS support
e92739d3 815 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
c0f40859 816 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
602ad3b3
JL
817 CONFIG_CMD_PCI * pciinfo
818 CONFIG_CMD_PCMCIA * PCMCIA support
819 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
820 host
821 CONFIG_CMD_PORTIO * Port I/O
ff048ea9 822 CONFIG_CMD_READ * Read raw data from partition
602ad3b3
JL
823 CONFIG_CMD_REGINFO * Register dump
824 CONFIG_CMD_RUN run command in env variable
d304931f 825 CONFIG_CMD_SANDBOX * sb command to access sandbox features
602ad3b3 826 CONFIG_CMD_SAVES * save S record dump
602ad3b3
JL
827 CONFIG_CMD_SDRAM * print SDRAM configuration information
828 (requires CONFIG_CMD_I2C)
f61ec45e 829 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
7d861d95 830 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
74de7aef 831 CONFIG_CMD_SOURCE "source" command Support
602ad3b3 832 CONFIG_CMD_SPI * SPI serial bus support
7a83af07 833 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
1fb7cd49 834 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
da83bcd7
JH
835 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
836 CONFIG_CMD_TIMER * access to the system tick timer
602ad3b3 837 CONFIG_CMD_USB * USB support
602ad3b3 838 CONFIG_CMD_CDP * Cisco Discover Protocol support
4d98b5c8 839 CONFIG_CMD_XIMG Load part of Multi Image
89c8230d 840 CONFIG_CMD_UUID * Generate random UUID or GUID string
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WD
841
842 EXAMPLE: If you want all functions except of network
843 support you can write:
844
602ad3b3
JL
845 #include "config_cmd_all.h"
846 #undef CONFIG_CMD_NET
c609719b 847
213bf8c8
GVB
848 Other Commands:
849 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
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WD
850
851 Note: Don't enable the "icache" and "dcache" commands
602ad3b3 852 (configuration option CONFIG_CMD_CACHE) unless you know
43d9616c 853 what you (and your U-Boot users) are doing. Data
5b8e76c3 854 cache cannot be enabled on systems like the
907208c4 855 8xx (where accesses to the IMMR region must be
43d9616c
WD
856 uncached), and it cannot be disabled on all other
857 systems where we (mis-) use the data cache to hold an
858 initial stack and some data.
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WD
859
860
861 XXX - this list needs to get updated!
862
302a6487
SG
863- Removal of commands
864 If no commands are needed to boot, you can disable
865 CONFIG_CMDLINE to remove them. In this case, the command line
866 will not be available, and when U-Boot wants to execute the
867 boot command (on start-up) it will call board_run_command()
868 instead. This can reduce image size significantly for very
869 simple boot procedures.
870
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WD
871- Regular expression support:
872 CONFIG_REGEX
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WD
873 If this variable is defined, U-Boot is linked against
874 the SLRE (Super Light Regular Expression) library,
875 which adds regex support to some commands, as for
876 example "env grep" and "setexpr".
a5ecbe62 877
45ba8077
SG
878- Device tree:
879 CONFIG_OF_CONTROL
880 If this variable is defined, U-Boot will use a device tree
881 to configure its devices, instead of relying on statically
882 compiled #defines in the board file. This option is
883 experimental and only available on a few boards. The device
884 tree is available in the global data as gd->fdt_blob.
885
2c0f79e4 886 U-Boot needs to get its device tree from somewhere. This can
82f766d1 887 be done using one of the three options below:
bbb0b128
SG
888
889 CONFIG_OF_EMBED
890 If this variable is defined, U-Boot will embed a device tree
891 binary in its image. This device tree file should be in the
892 board directory and called <soc>-<board>.dts. The binary file
893 is then picked up in board_init_f() and made available through
894 the global data structure as gd->blob.
45ba8077 895
2c0f79e4
SG
896 CONFIG_OF_SEPARATE
897 If this variable is defined, U-Boot will build a device tree
898 binary. It will be called u-boot.dtb. Architecture-specific
899 code will locate it at run-time. Generally this works by:
900
901 cat u-boot.bin u-boot.dtb >image.bin
902
903 and in fact, U-Boot does this for you, creating a file called
904 u-boot-dtb.bin which is useful in the common case. You can
905 still use the individual files if you need something more
906 exotic.
907
82f766d1
AD
908 CONFIG_OF_BOARD
909 If this variable is defined, U-Boot will use the device tree
910 provided by the board at runtime instead of embedding one with
911 the image. Only boards defining board_fdt_blob_setup() support
912 this option (see include/fdtdec.h file).
913
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914- Watchdog:
915 CONFIG_WATCHDOG
916 If this variable is defined, it enables watchdog
6abe6fb6 917 support for the SoC. There must be support in the SoC
907208c4
CL
918 specific code for a watchdog. For the 8xx
919 CPUs, the SIU Watchdog feature is enabled in the SYPCR
920 register. When supported for a specific SoC is
921 available, then no further board specific code should
922 be needed to use it.
6abe6fb6
DZ
923
924 CONFIG_HW_WATCHDOG
925 When using a watchdog circuitry external to the used
926 SoC, then define this variable and provide board
927 specific code for the "hw_watchdog_reset" function.
c609719b 928
7bae0d6f
HS
929 CONFIG_AT91_HW_WDT_TIMEOUT
930 specify the timeout in seconds. default 2 seconds.
931
c1551ea8
SR
932- U-Boot Version:
933 CONFIG_VERSION_VARIABLE
934 If this variable is defined, an environment variable
935 named "ver" is created by U-Boot showing the U-Boot
936 version as printed by the "version" command.
a1ea8e51
BT
937 Any change to this variable will be reverted at the
938 next reset.
c1551ea8 939
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WD
940- Real-Time Clock:
941
602ad3b3 942 When CONFIG_CMD_DATE is selected, the type of the RTC
c609719b
WD
943 has to be selected, too. Define exactly one of the
944 following options:
945
c609719b 946 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
4e8b7544 947 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
c609719b 948 CONFIG_RTC_MC146818 - use MC146818 RTC
1cb8e980 949 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
c609719b 950 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
7f70e853 951 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
412921d2 952 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
3bac3513 953 CONFIG_RTC_DS164x - use Dallas DS164x RTC
9536dfcc 954 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
4c0d4c3b 955 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
2bd3cab3 956 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
71d19f30
HS
957 CONFIG_SYS_RV3029_TCR - enable trickle charger on
958 RV3029 RTC.
c609719b 959
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WD
960 Note that if the RTC uses I2C, then the I2C interface
961 must also be configured. See I2C Support, below.
962
e92739d3
PT
963- GPIO Support:
964 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
e92739d3 965
5dec49ca
CP
966 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
967 chip-ngpio pairs that tell the PCA953X driver the number of
968 pins supported by a particular chip.
969
e92739d3
PT
970 Note that if the GPIO device uses I2C, then the I2C interface
971 must also be configured. See I2C Support, below.
972
aa53233a
SG
973- I/O tracing:
974 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
975 accesses and can checksum them or write a list of them out
976 to memory. See the 'iotrace' command for details. This is
977 useful for testing device drivers since it can confirm that
978 the driver behaves the same way before and after a code
979 change. Currently this is supported on sandbox and arm. To
980 add support for your architecture, add '#include <iotrace.h>'
981 to the bottom of arch/<arch>/include/asm/io.h and test.
982
983 Example output from the 'iotrace stats' command is below.
984 Note that if the trace buffer is exhausted, the checksum will
985 still continue to operate.
986
987 iotrace is enabled
988 Start: 10000000 (buffer start address)
989 Size: 00010000 (buffer size)
990 Offset: 00000120 (current buffer offset)
991 Output: 10000120 (start + offset)
992 Count: 00000018 (number of trace records)
993 CRC32: 9526fb66 (CRC32 of all trace records)
994
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WD
995- Timestamp Support:
996
43d9616c
WD
997 When CONFIG_TIMESTAMP is selected, the timestamp
998 (date and time) of an image is printed by image
999 commands like bootm or iminfo. This option is
602ad3b3 1000 automatically enabled when you select CONFIG_CMD_DATE .
c609719b 1001
923c46f9
KP
1002- Partition Labels (disklabels) Supported:
1003 Zero or more of the following:
1004 CONFIG_MAC_PARTITION Apple's MacOS partition table.
923c46f9
KP
1005 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1006 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1007 bootloader. Note 2TB partition limit; see
1008 disk/part_efi.c
1009 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
c609719b 1010
fc843a02 1011 If IDE or SCSI support is enabled (CONFIG_IDE or
c649e3c9 1012 CONFIG_SCSI) you must configure support for at
923c46f9 1013 least one non-MTD partition type as well.
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1014
1015- IDE Reset method:
4d13cbad
WD
1016 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1017 board configurations files but used nowhere!
c609719b 1018
4d13cbad
WD
1019 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1020 be performed by calling the function
1021 ide_set_reset(int reset)
1022 which has to be defined in a board specific file
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1023
1024- ATAPI Support:
1025 CONFIG_ATAPI
1026
1027 Set this to enable ATAPI support.
1028
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WD
1029- LBA48 Support
1030 CONFIG_LBA48
1031
1032 Set this to enable support for disks larger than 137GB
4b142feb 1033 Also look at CONFIG_SYS_64BIT_LBA.
c40b2956
WD
1034 Whithout these , LBA48 support uses 32bit variables and will 'only'
1035 support disks up to 2.1TB.
1036
6d0f6bcf 1037 CONFIG_SYS_64BIT_LBA:
c40b2956
WD
1038 When enabled, makes the IDE subsystem use 64bit sector addresses.
1039 Default is 32bit.
1040
c609719b 1041- SCSI Support:
6d0f6bcf
JCPV
1042 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1043 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1044 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
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WD
1045 maximum numbers of LUNs, SCSI ID's and target
1046 devices.
c609719b 1047
93e14596
WD
1048 The environment variable 'scsidevs' is set to the number of
1049 SCSI devices found during the last scan.
447c031b 1050
c609719b 1051- NETWORK Support (PCI):
682011ff 1052 CONFIG_E1000
ce5207e1
KM
1053 Support for Intel 8254x/8257x gigabit chips.
1054
1055 CONFIG_E1000_SPI
1056 Utility code for direct access to the SPI bus on Intel 8257x.
1057 This does not do anything useful unless you set at least one
1058 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1059
1060 CONFIG_E1000_SPI_GENERIC
1061 Allow generic access to the SPI bus on the Intel 8257x, for
1062 example with the "sspi" command.
1063
1064 CONFIG_CMD_E1000
1065 Management command for E1000 devices. When used on devices
1066 with SPI support you can reprogram the EEPROM from U-Boot.
53cf9435 1067
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WD
1068 CONFIG_EEPRO100
1069 Support for Intel 82557/82559/82559ER chips.
11ccc33f 1070 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
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1071 write routine for first time initialisation.
1072
1073 CONFIG_TULIP
1074 Support for Digital 2114x chips.
1075 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1076 modem chip initialisation (KS8761/QS6611).
1077
1078 CONFIG_NATSEMI
1079 Support for National dp83815 chips.
1080
1081 CONFIG_NS8382X
1082 Support for National dp8382[01] gigabit chips.
1083
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WD
1084- NETWORK Support (other):
1085
c041e9d2
JS
1086 CONFIG_DRIVER_AT91EMAC
1087 Support for AT91RM9200 EMAC.
1088
1089 CONFIG_RMII
1090 Define this to use reduced MII inteface
1091
1092 CONFIG_DRIVER_AT91EMAC_QUIET
1093 If this defined, the driver is quiet.
1094 The driver doen't show link status messages.
1095
efdd7319
RH
1096 CONFIG_CALXEDA_XGMAC
1097 Support for the Calxeda XGMAC device
1098
3bb46d23 1099 CONFIG_LAN91C96
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WD
1100 Support for SMSC's LAN91C96 chips.
1101
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WD
1102 CONFIG_LAN91C96_USE_32_BIT
1103 Define this to enable 32 bit addressing
1104
3bb46d23 1105 CONFIG_SMC91111
f39748ae
WD
1106 Support for SMSC's LAN91C111 chip
1107
1108 CONFIG_SMC91111_BASE
1109 Define this to hold the physical address
1110 of the device (I/O space)
1111
1112 CONFIG_SMC_USE_32_BIT
1113 Define this if data bus is 32 bits
1114
1115 CONFIG_SMC_USE_IOFUNCS
1116 Define this to use i/o functions instead of macros
1117 (some hardware wont work with macros)
1118
dc02bada
HS
1119 CONFIG_DRIVER_TI_EMAC
1120 Support for davinci emac
1121
1122 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1123 Define this if you have more then 3 PHYs.
1124
b3dbf4a5
ML
1125 CONFIG_FTGMAC100
1126 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1127
1128 CONFIG_FTGMAC100_EGIGA
1129 Define this to use GE link update with gigabit PHY.
1130 Define this if FTGMAC100 is connected to gigabit PHY.
1131 If your system has 10/100 PHY only, it might not occur
1132 wrong behavior. Because PHY usually return timeout or
1133 useless data when polling gigabit status and gigabit
1134 control registers. This behavior won't affect the
1135 correctnessof 10/100 link speed update.
1136
c2fff331 1137 CONFIG_SMC911X
557b377d
JG
1138 Support for SMSC's LAN911x and LAN921x chips
1139
c2fff331 1140 CONFIG_SMC911X_BASE
557b377d
JG
1141 Define this to hold the physical address
1142 of the device (I/O space)
1143
c2fff331 1144 CONFIG_SMC911X_32_BIT
557b377d
JG
1145 Define this if data bus is 32 bits
1146
c2fff331 1147 CONFIG_SMC911X_16_BIT
557b377d
JG
1148 Define this if data bus is 16 bits. If your processor
1149 automatically converts one 32 bit word to two 16 bit
c2fff331 1150 words you may also try CONFIG_SMC911X_32_BIT.
557b377d 1151
3d0075fa
YS
1152 CONFIG_SH_ETHER
1153 Support for Renesas on-chip Ethernet controller
1154
1155 CONFIG_SH_ETHER_USE_PORT
1156 Define the number of ports to be used
1157
1158 CONFIG_SH_ETHER_PHY_ADDR
1159 Define the ETH PHY's address
1160
68260aab
YS
1161 CONFIG_SH_ETHER_CACHE_WRITEBACK
1162 If this option is set, the driver enables cache flush.
1163
b2f97cf2
HS
1164- PWM Support:
1165 CONFIG_PWM_IMX
5052e819 1166 Support for PWM module on the imx6.
b2f97cf2 1167
5e124724 1168- TPM Support:
90899cc0
CC
1169 CONFIG_TPM
1170 Support TPM devices.
1171
0766ad2f
CR
1172 CONFIG_TPM_TIS_INFINEON
1173 Support for Infineon i2c bus TPM devices. Only one device
1b393db5
TWHT
1174 per system is supported at this time.
1175
1b393db5
TWHT
1176 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1177 Define the burst count bytes upper limit
1178
3aa74088
CR
1179 CONFIG_TPM_ST33ZP24
1180 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
1181
1182 CONFIG_TPM_ST33ZP24_I2C
1183 Support for STMicroelectronics ST33ZP24 I2C devices.
1184 Requires TPM_ST33ZP24 and I2C.
1185
b75fdc11
CR
1186 CONFIG_TPM_ST33ZP24_SPI
1187 Support for STMicroelectronics ST33ZP24 SPI devices.
1188 Requires TPM_ST33ZP24 and SPI.
1189
c01939c7
DE
1190 CONFIG_TPM_ATMEL_TWI
1191 Support for Atmel TWI TPM device. Requires I2C support.
1192
90899cc0 1193 CONFIG_TPM_TIS_LPC
5e124724
VB
1194 Support for generic parallel port TPM devices. Only one device
1195 per system is supported at this time.
1196
1197 CONFIG_TPM_TIS_BASE_ADDRESS
1198 Base address where the generic TPM device is mapped
1199 to. Contemporary x86 systems usually map it at
1200 0xfed40000.
1201
be6c1529
RP
1202 CONFIG_CMD_TPM
1203 Add tpm monitor functions.
1204 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1205 provides monitor access to authorized functions.
1206
1207 CONFIG_TPM
1208 Define this to enable the TPM support library which provides
1209 functional interfaces to some TPM commands.
1210 Requires support for a TPM device.
1211
1212 CONFIG_TPM_AUTH_SESSIONS
1213 Define this to enable authorized functions in the TPM library.
1214 Requires CONFIG_TPM and CONFIG_SHA1.
1215
c609719b
WD
1216- USB Support:
1217 At the moment only the UHCI host controller is
064b55cf 1218 supported (PIP405, MIP405); define
c609719b
WD
1219 CONFIG_USB_UHCI to enable it.
1220 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
30d56fae 1221 and define CONFIG_USB_STORAGE to enable the USB
c609719b
WD
1222 storage devices.
1223 Note:
1224 Supported are USB Keyboards and USB Floppy drives
1225 (TEAC FD-05PUB).
4d13cbad 1226
9ab4ce22
SG
1227 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1228 txfilltuning field in the EHCI controller on reset.
1229
6e9e0626
OT
1230 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1231 HW module registers.
1232
16c8d5e7
WD
1233- USB Device:
1234 Define the below if you wish to use the USB console.
1235 Once firmware is rebuilt from a serial console issue the
1236 command "setenv stdin usbtty; setenv stdout usbtty" and
11ccc33f 1237 attach your USB cable. The Unix command "dmesg" should print
16c8d5e7
WD
1238 it has found a new device. The environment variable usbtty
1239 can be set to gserial or cdc_acm to enable your device to
386eda02 1240 appear to a USB host as a Linux gserial device or a
16c8d5e7
WD
1241 Common Device Class Abstract Control Model serial device.
1242 If you select usbtty = gserial you should be able to enumerate
1243 a Linux host by
1244 # modprobe usbserial vendor=0xVendorID product=0xProductID
1245 else if using cdc_acm, simply setting the environment
1246 variable usbtty to be cdc_acm should suffice. The following
1247 might be defined in YourBoardName.h
386eda02 1248
16c8d5e7
WD
1249 CONFIG_USB_DEVICE
1250 Define this to build a UDC device
1251
1252 CONFIG_USB_TTY
1253 Define this to have a tty type of device available to
1254 talk to the UDC device
386eda02 1255
f9da0f89
VK
1256 CONFIG_USBD_HS
1257 Define this to enable the high speed support for usb
1258 device and usbtty. If this feature is enabled, a routine
1259 int is_usbd_high_speed(void)
1260 also needs to be defined by the driver to dynamically poll
1261 whether the enumeration has succeded at high speed or full
1262 speed.
1263
6d0f6bcf 1264 CONFIG_SYS_CONSOLE_IS_IN_ENV
16c8d5e7
WD
1265 Define this if you want stdin, stdout &/or stderr to
1266 be set to usbtty.
1267
386eda02 1268 If you have a USB-IF assigned VendorID then you may wish to
16c8d5e7 1269 define your own vendor specific values either in BoardName.h
386eda02 1270 or directly in usbd_vendor_info.h. If you don't define
16c8d5e7
WD
1271 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1272 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1273 should pretend to be a Linux device to it's target host.
1274
1275 CONFIG_USBD_MANUFACTURER
1276 Define this string as the name of your company for
1277 - CONFIG_USBD_MANUFACTURER "my company"
386eda02 1278
16c8d5e7
WD
1279 CONFIG_USBD_PRODUCT_NAME
1280 Define this string as the name of your product
1281 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1282
1283 CONFIG_USBD_VENDORID
1284 Define this as your assigned Vendor ID from the USB
1285 Implementors Forum. This *must* be a genuine Vendor ID
1286 to avoid polluting the USB namespace.
1287 - CONFIG_USBD_VENDORID 0xFFFF
386eda02 1288
16c8d5e7
WD
1289 CONFIG_USBD_PRODUCTID
1290 Define this as the unique Product ID
1291 for your device
1292 - CONFIG_USBD_PRODUCTID 0xFFFF
4d13cbad 1293
d70a560f
IG
1294- ULPI Layer Support:
1295 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1296 the generic ULPI layer. The generic layer accesses the ULPI PHY
1297 via the platform viewport, so you need both the genric layer and
1298 the viewport enabled. Currently only Chipidea/ARC based
1299 viewport is supported.
1300 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1301 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
6d365ea0
LS
1302 If your ULPI phy needs a different reference clock than the
1303 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1304 the appropriate value in Hz.
c609719b 1305
71f95118 1306- MMC Support:
8bde7f77
WD
1307 The MMC controller on the Intel PXA is supported. To
1308 enable this define CONFIG_MMC. The MMC can be
1309 accessed from the boot prompt by mapping the device
71f95118 1310 to physical memory similar to flash. Command line is
602ad3b3
JL
1311 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1312 the FAT fs. This is enabled with CONFIG_CMD_FAT.
71f95118 1313
afb35666
YS
1314 CONFIG_SH_MMCIF
1315 Support for Renesas on-chip MMCIF controller
1316
1317 CONFIG_SH_MMCIF_ADDR
1318 Define the base address of MMCIF registers
1319
1320 CONFIG_SH_MMCIF_CLK
1321 Define the clock frequency for MMCIF
1322
1fd93c6e
PA
1323 CONFIG_SUPPORT_EMMC_BOOT
1324 Enable some additional features of the eMMC boot partitions.
1325
1326 CONFIG_SUPPORT_EMMC_RPMB
1327 Enable the commands for reading, writing and programming the
1328 key for the Replay Protection Memory Block partition in eMMC.
1329
b3ba6e94 1330- USB Device Firmware Update (DFU) class support:
01acd6ab 1331 CONFIG_USB_FUNCTION_DFU
b3ba6e94
TR
1332 This enables the USB portion of the DFU USB class
1333
1334 CONFIG_CMD_DFU
1335 This enables the command "dfu" which is used to have
1336 U-Boot create a DFU class device via USB. This command
1337 requires that the "dfu_alt_info" environment variable be
1338 set and define the alt settings to expose to the host.
1339
1340 CONFIG_DFU_MMC
1341 This enables support for exposing (e)MMC devices via DFU.
1342
c6631764
PA
1343 CONFIG_DFU_NAND
1344 This enables support for exposing NAND devices via DFU.
1345
a9479f04
AM
1346 CONFIG_DFU_RAM
1347 This enables support for exposing RAM via DFU.
1348 Note: DFU spec refer to non-volatile memory usage, but
1349 allow usages beyond the scope of spec - here RAM usage,
1350 one that would help mostly the developer.
1351
e7e75c70
HS
1352 CONFIG_SYS_DFU_DATA_BUF_SIZE
1353 Dfu transfer uses a buffer before writing data to the
1354 raw storage device. Make the size (in bytes) of this buffer
1355 configurable. The size of this buffer is also configurable
1356 through the "dfu_bufsiz" environment variable.
1357
ea2453d5
PA
1358 CONFIG_SYS_DFU_MAX_FILE_SIZE
1359 When updating files rather than the raw storage device,
1360 we use a static buffer to copy the file into and then write
1361 the buffer once we've been given the whole file. Define
1362 this to the maximum filesize (in bytes) for the buffer.
1363 Default is 4 MiB if undefined.
1364
001a8319
HS
1365 DFU_DEFAULT_POLL_TIMEOUT
1366 Poll timeout [ms], is the timeout a device can send to the
1367 host. The host must wait for this timeout before sending
1368 a subsequent DFU_GET_STATUS request to the device.
1369
1370 DFU_MANIFEST_POLL_TIMEOUT
1371 Poll timeout [ms], which the device sends to the host when
1372 entering dfuMANIFEST state. Host waits this timeout, before
1373 sending again an USB request to the device.
1374
3aab70af 1375- USB Device Android Fastboot support:
17da3c0c
PK
1376 CONFIG_USB_FUNCTION_FASTBOOT
1377 This enables the USB part of the fastboot gadget
1378
3aab70af
SS
1379 CONFIG_CMD_FASTBOOT
1380 This enables the command "fastboot" which enables the Android
1381 fastboot mode for the platform's USB device. Fastboot is a USB
1382 protocol for downloading images, flashing and device control
1383 used on Android devices.
1384 See doc/README.android-fastboot for more information.
1385
1386 CONFIG_ANDROID_BOOT_IMAGE
1387 This enables support for booting images which use the Android
1388 image format header.
1389
a588d99a 1390 CONFIG_FASTBOOT_BUF_ADDR
3aab70af
SS
1391 The fastboot protocol requires a large memory buffer for
1392 downloads. Define this to the starting RAM address to use for
1393 downloaded images.
1394
a588d99a 1395 CONFIG_FASTBOOT_BUF_SIZE
3aab70af
SS
1396 The fastboot protocol requires a large memory buffer for
1397 downloads. This buffer should be as large as possible for a
1398 platform. Define this to the size available RAM for fastboot.
d1b5ed07
SR
1399
1400 CONFIG_FASTBOOT_FLASH
1401 The fastboot protocol includes a "flash" command for writing
1402 the downloaded image to a non-volatile storage device. Define
1403 this to enable the "fastboot flash" command.
1404
1405 CONFIG_FASTBOOT_FLASH_MMC_DEV
1406 The fastboot "flash" command requires additional information
1407 regarding the non-volatile storage device. Define this to
1408 the eMMC device that fastboot should use to store the image.
3aab70af 1409
0ff7e585
SR
1410 CONFIG_FASTBOOT_GPT_NAME
1411 The fastboot "flash" command supports writing the downloaded
1412 image to the Protective MBR and the Primary GUID Partition
1413 Table. (Additionally, this downloaded image is post-processed
1414 to generate and write the Backup GUID Partition Table.)
1415 This occurs when the specified "partition name" on the
1416 "fastboot flash" command line matches this value.
6f6c8630 1417 The default is "gpt" if undefined.
0ff7e585 1418
b6dd69a4
PK
1419 CONFIG_FASTBOOT_MBR_NAME
1420 The fastboot "flash" command supports writing the downloaded
1421 image to DOS MBR.
1422 This occurs when the "partition name" specified on the
1423 "fastboot flash" command line matches this value.
1424 If not defined the default value "mbr" is used.
1425
6705d81e 1426- Journaling Flash filesystem support:
b2482dff 1427 CONFIG_JFFS2_NAND
6705d81e
WD
1428 Define these for a default partition on a NAND device
1429
6d0f6bcf
JCPV
1430 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1431 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
6705d81e
WD
1432 Define these for a default partition on a NOR device
1433
c609719b 1434- Keyboard Support:
39f615ed
SG
1435 See Kconfig help for available keyboard drivers.
1436
1437 CONFIG_KEYBOARD
1438
1439 Define this to enable a custom keyboard support.
1440 This simply calls drv_keyboard_init() which must be
1441 defined in your board-specific files. This option is deprecated
1442 and is only used by novena. For new boards, use driver model
1443 instead.
c609719b
WD
1444
1445- Video support:
7d3053fb 1446 CONFIG_FSL_DIU_FB
04e5ae79 1447 Enable the Freescale DIU video driver. Reference boards for
7d3053fb
TT
1448 SOCs that have a DIU should define this macro to enable DIU
1449 support, and should also define these other macros:
1450
1451 CONFIG_SYS_DIU_ADDR
1452 CONFIG_VIDEO
7d3053fb
TT
1453 CONFIG_CFB_CONSOLE
1454 CONFIG_VIDEO_SW_CURSOR
1455 CONFIG_VGA_AS_SINGLE_DEVICE
1456 CONFIG_VIDEO_LOGO
1457 CONFIG_VIDEO_BMP_LOGO
1458
ba8e76bd
TT
1459 The DIU driver will look for the 'video-mode' environment
1460 variable, and if defined, enable the DIU as a console during
8eca9439 1461 boot. See the documentation file doc/README.video for a
ba8e76bd 1462 description of this variable.
7d3053fb 1463
c609719b
WD
1464- LCD Support: CONFIG_LCD
1465
1466 Define this to enable LCD support (for output to LCD
1467 display); also select one of the supported displays
1468 by defining one of these:
1469
39cf4804
SP
1470 CONFIG_ATMEL_LCD:
1471
1472 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1473
fd3103bb 1474 CONFIG_NEC_NL6448AC33:
c609719b 1475
fd3103bb 1476 NEC NL6448AC33-18. Active, color, single scan.
c609719b 1477
fd3103bb 1478 CONFIG_NEC_NL6448BC20
c609719b 1479
fd3103bb
WD
1480 NEC NL6448BC20-08. 6.5", 640x480.
1481 Active, color, single scan.
1482
1483 CONFIG_NEC_NL6448BC33_54
1484
1485 NEC NL6448BC33-54. 10.4", 640x480.
c609719b
WD
1486 Active, color, single scan.
1487
1488 CONFIG_SHARP_16x9
1489
1490 Sharp 320x240. Active, color, single scan.
1491 It isn't 16x9, and I am not sure what it is.
1492
1493 CONFIG_SHARP_LQ64D341
1494
1495 Sharp LQ64D341 display, 640x480.
1496 Active, color, single scan.
1497
1498 CONFIG_HLD1045
1499
1500 HLD1045 display, 640x480.
1501 Active, color, single scan.
1502
1503 CONFIG_OPTREX_BW
1504
1505 Optrex CBL50840-2 NF-FW 99 22 M5
1506 or
1507 Hitachi LMG6912RPFC-00T
1508 or
1509 Hitachi SP14Q002
1510
1511 320x240. Black & white.
1512
676d319e
SG
1513 CONFIG_LCD_ALIGNMENT
1514
b445bbb4 1515 Normally the LCD is page-aligned (typically 4KB). If this is
676d319e
SG
1516 defined then the LCD will be aligned to this value instead.
1517 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1518 here, since it is cheaper to change data cache settings on
1519 a per-section basis.
1520
1521
604c7d4a
HP
1522 CONFIG_LCD_ROTATION
1523
1524 Sometimes, for example if the display is mounted in portrait
1525 mode or even if it's mounted landscape but rotated by 180degree,
1526 we need to rotate our content of the display relative to the
1527 framebuffer, so that user can read the messages which are
1528 printed out.
1529 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1530 initialized with a given rotation from "vl_rot" out of
1531 "vidinfo_t" which is provided by the board specific code.
1532 The value for vl_rot is coded as following (matching to
1533 fbcon=rotate:<n> linux-kernel commandline):
1534 0 = no rotation respectively 0 degree
1535 1 = 90 degree rotation
1536 2 = 180 degree rotation
1537 3 = 270 degree rotation
1538
1539 If CONFIG_LCD_ROTATION is not defined, the console will be
1540 initialized with 0degree rotation.
1541
45d7f525
TWHT
1542 CONFIG_LCD_BMP_RLE8
1543
1544 Support drawing of RLE8-compressed bitmaps on the LCD.
1545
735987c5
TWHT
1546 CONFIG_I2C_EDID
1547
1548 Enables an 'i2c edid' command which can read EDID
1549 information over I2C from an attached LCD display.
1550
7152b1d0 1551- Splash Screen Support: CONFIG_SPLASH_SCREEN
d791b1dc 1552
8bde7f77
WD
1553 If this option is set, the environment is checked for
1554 a variable "splashimage". If found, the usual display
1555 of logo, copyright and system information on the LCD
e94d2cd9 1556 is suppressed and the BMP image at the address
8bde7f77
WD
1557 specified in "splashimage" is loaded instead. The
1558 console is redirected to the "nulldev", too. This
1559 allows for a "silent" boot where a splash screen is
1560 loaded very quickly after power-on.
d791b1dc 1561
c0880485
NK
1562 CONFIG_SPLASHIMAGE_GUARD
1563
1564 If this option is set, then U-Boot will prevent the environment
1565 variable "splashimage" from being set to a problematic address
ab5645f1 1566 (see doc/README.displaying-bmps).
c0880485
NK
1567 This option is useful for targets where, due to alignment
1568 restrictions, an improperly aligned BMP image will cause a data
1569 abort. If you think you will not have problems with unaligned
1570 accesses (for example because your toolchain prevents them)
1571 there is no need to set this option.
1572
1ca298ce
MW
1573 CONFIG_SPLASH_SCREEN_ALIGN
1574
1575 If this option is set the splash image can be freely positioned
1576 on the screen. Environment variable "splashpos" specifies the
1577 position as "x,y". If a positive number is given it is used as
1578 number of pixel from left/top. If a negative number is given it
1579 is used as number of pixel from right/bottom. You can also
1580 specify 'm' for centering the image.
1581
1582 Example:
1583 setenv splashpos m,m
1584 => image at center of screen
1585
1586 setenv splashpos 30,20
1587 => image at x = 30 and y = 20
1588
1589 setenv splashpos -10,m
1590 => vertically centered image
1591 at x = dspWidth - bmpWidth - 9
1592
98f4a3df
SR
1593- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1594
1595 If this option is set, additionally to standard BMP
1596 images, gzipped BMP images can be displayed via the
1597 splashscreen support or the bmp command.
1598
d5011762
AG
1599- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1600
1601 If this option is set, 8-bit RLE compressed BMP images
1602 can be displayed via the splashscreen support or the
1603 bmp command.
1604
c29fdfc1 1605- Compression support:
8ef70478
KC
1606 CONFIG_GZIP
1607
1608 Enabled by default to support gzip compressed images.
1609
c29fdfc1
WD
1610 CONFIG_BZIP2
1611
1612 If this option is set, support for bzip2 compressed
1613 images is included. If not, only uncompressed and gzip
1614 compressed images are supported.
1615
42d1f039 1616 NOTE: the bzip2 algorithm requires a lot of RAM, so
6d0f6bcf 1617 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
42d1f039 1618 be at least 4MB.
d791b1dc 1619
17ea1177
WD
1620- MII/PHY support:
1621 CONFIG_PHY_ADDR
1622
1623 The address of PHY on MII bus.
1624
1625 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1626
1627 The clock frequency of the MII bus
1628
17ea1177
WD
1629 CONFIG_PHY_RESET_DELAY
1630
1631 Some PHY like Intel LXT971A need extra delay after
1632 reset before any MII register access is possible.
1633 For such PHY, set this option to the usec delay
1634 required. (minimum 300usec for LXT971A)
1635
1636 CONFIG_PHY_CMD_DELAY (ppc4xx)
1637
1638 Some PHY like Intel LXT971A need extra delay after
1639 command issued before MII status register can be read
1640
c609719b
WD
1641- IP address:
1642 CONFIG_IPADDR
1643
1644 Define a default value for the IP address to use for
11ccc33f 1645 the default Ethernet interface, in case this is not
c609719b 1646 determined through e.g. bootp.
1ebcd654 1647 (Environment variable "ipaddr")
c609719b
WD
1648
1649- Server IP address:
1650 CONFIG_SERVERIP
1651
11ccc33f 1652 Defines a default value for the IP address of a TFTP
c609719b 1653 server to contact when using the "tftboot" command.
1ebcd654 1654 (Environment variable "serverip")
c609719b 1655
97cfe861
RG
1656 CONFIG_KEEP_SERVERADDR
1657
1658 Keeps the server's MAC address, in the env 'serveraddr'
1659 for passing to bootargs (like Linux's netconsole option)
1660
1ebcd654
WD
1661- Gateway IP address:
1662 CONFIG_GATEWAYIP
1663
1664 Defines a default value for the IP address of the
1665 default router where packets to other networks are
1666 sent to.
1667 (Environment variable "gatewayip")
1668
1669- Subnet mask:
1670 CONFIG_NETMASK
1671
1672 Defines a default value for the subnet mask (or
1673 routing prefix) which is used to determine if an IP
1674 address belongs to the local subnet or needs to be
1675 forwarded through a router.
1676 (Environment variable "netmask")
1677
53a5c424
DU
1678- Multicast TFTP Mode:
1679 CONFIG_MCAST_TFTP
1680
1681 Defines whether you want to support multicast TFTP as per
1682 rfc-2090; for example to work with atftp. Lets lots of targets
11ccc33f 1683 tftp down the same boot image concurrently. Note: the Ethernet
53a5c424
DU
1684 driver in use must provide a function: mcast() to join/leave a
1685 multicast group.
1686
c609719b
WD
1687- BOOTP Recovery Mode:
1688 CONFIG_BOOTP_RANDOM_DELAY
1689
1690 If you have many targets in a network that try to
1691 boot using BOOTP, you may want to avoid that all
1692 systems send out BOOTP requests at precisely the same
1693 moment (which would happen for instance at recovery
1694 from a power failure, when all systems will try to
1695 boot, thus flooding the BOOTP server. Defining
1696 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1697 inserted before sending out BOOTP requests. The
6c33c785 1698 following delays are inserted then:
c609719b
WD
1699
1700 1st BOOTP request: delay 0 ... 1 sec
1701 2nd BOOTP request: delay 0 ... 2 sec
1702 3rd BOOTP request: delay 0 ... 4 sec
1703 4th and following
1704 BOOTP requests: delay 0 ... 8 sec
1705
92ac8acc
TR
1706 CONFIG_BOOTP_ID_CACHE_SIZE
1707
1708 BOOTP packets are uniquely identified using a 32-bit ID. The
1709 server will copy the ID from client requests to responses and
1710 U-Boot will use this to determine if it is the destination of
1711 an incoming response. Some servers will check that addresses
1712 aren't in use before handing them out (usually using an ARP
1713 ping) and therefore take up to a few hundred milliseconds to
1714 respond. Network congestion may also influence the time it
1715 takes for a response to make it back to the client. If that
1716 time is too long, U-Boot will retransmit requests. In order
1717 to allow earlier responses to still be accepted after these
1718 retransmissions, U-Boot's BOOTP client keeps a small cache of
1719 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1720 cache. The default is to keep IDs for up to four outstanding
1721 requests. Increasing this will allow U-Boot to accept offers
1722 from a BOOTP client in networks with unusually high latency.
1723
fe389a82 1724- DHCP Advanced Options:
1fe80d79
JL
1725 You can fine tune the DHCP functionality by defining
1726 CONFIG_BOOTP_* symbols:
1727
1728 CONFIG_BOOTP_SUBNETMASK
1729 CONFIG_BOOTP_GATEWAY
1730 CONFIG_BOOTP_HOSTNAME
1731 CONFIG_BOOTP_NISDOMAIN
1732 CONFIG_BOOTP_BOOTPATH
1733 CONFIG_BOOTP_BOOTFILESIZE
1734 CONFIG_BOOTP_DNS
1735 CONFIG_BOOTP_DNS2
1736 CONFIG_BOOTP_SEND_HOSTNAME
1737 CONFIG_BOOTP_NTPSERVER
1738 CONFIG_BOOTP_TIMEOFFSET
1739 CONFIG_BOOTP_VENDOREX
2c00e099 1740 CONFIG_BOOTP_MAY_FAIL
fe389a82 1741
5d110f0a
WC
1742 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1743 environment variable, not the BOOTP server.
fe389a82 1744
2c00e099
JH
1745 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1746 after the configured retry count, the call will fail
1747 instead of starting over. This can be used to fail over
1748 to Link-local IP address configuration if the DHCP server
1749 is not available.
1750
fe389a82
SR
1751 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1752 serverip from a DHCP server, it is possible that more
1753 than one DNS serverip is offered to the client.
1754 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1755 serverip will be stored in the additional environment
1756 variable "dnsip2". The first DNS serverip is always
1757 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1fe80d79 1758 is defined.
fe389a82
SR
1759
1760 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1761 to do a dynamic update of a DNS server. To do this, they
1762 need the hostname of the DHCP requester.
5d110f0a 1763 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1fe80d79
JL
1764 of the "hostname" environment variable is passed as
1765 option 12 to the DHCP server.
fe389a82 1766
d9a2f416
AV
1767 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1768
1769 A 32bit value in microseconds for a delay between
1770 receiving a "DHCP Offer" and sending the "DHCP Request".
1771 This fixes a problem with certain DHCP servers that don't
1772 respond 100% of the time to a "DHCP request". E.g. On an
1773 AT91RM9200 processor running at 180MHz, this delay needed
1774 to be *at least* 15,000 usec before a Windows Server 2003
1775 DHCP server would reply 100% of the time. I recommend at
1776 least 50,000 usec to be safe. The alternative is to hope
1777 that one of the retries will be successful but note that
1778 the DHCP timeout and retry process takes a longer than
1779 this delay.
1780
d22c338e
JH
1781 - Link-local IP address negotiation:
1782 Negotiate with other link-local clients on the local network
1783 for an address that doesn't require explicit configuration.
1784 This is especially useful if a DHCP server cannot be guaranteed
1785 to exist in all environments that the device must operate.
1786
1787 See doc/README.link-local for more information.
1788
a3d991bd 1789 - CDP Options:
6e592385 1790 CONFIG_CDP_DEVICE_ID
a3d991bd
WD
1791
1792 The device id used in CDP trigger frames.
1793
1794 CONFIG_CDP_DEVICE_ID_PREFIX
1795
1796 A two character string which is prefixed to the MAC address
1797 of the device.
1798
1799 CONFIG_CDP_PORT_ID
1800
1801 A printf format string which contains the ascii name of
1802 the port. Normally is set to "eth%d" which sets
11ccc33f 1803 eth0 for the first Ethernet, eth1 for the second etc.
a3d991bd
WD
1804
1805 CONFIG_CDP_CAPABILITIES
1806
1807 A 32bit integer which indicates the device capabilities;
1808 0x00000010 for a normal host which does not forwards.
1809
1810 CONFIG_CDP_VERSION
1811
1812 An ascii string containing the version of the software.
1813
1814 CONFIG_CDP_PLATFORM
1815
1816 An ascii string containing the name of the platform.
1817
1818 CONFIG_CDP_TRIGGER
1819
1820 A 32bit integer sent on the trigger.
1821
1822 CONFIG_CDP_POWER_CONSUMPTION
1823
1824 A 16bit integer containing the power consumption of the
1825 device in .1 of milliwatts.
1826
1827 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1828
1829 A byte containing the id of the VLAN.
1830
79267edd 1831- Status LED: CONFIG_LED_STATUS
c609719b
WD
1832
1833 Several configurations allow to display the current
1834 status using a LED. For instance, the LED will blink
1835 fast while running U-Boot code, stop blinking as
1836 soon as a reply to a BOOTP request was received, and
1837 start blinking slow once the Linux kernel is running
1838 (supported by a status LED driver in the Linux
79267edd 1839 kernel). Defining CONFIG_LED_STATUS enables this
c609719b
WD
1840 feature in U-Boot.
1841
1df7bbba
IG
1842 Additional options:
1843
79267edd 1844 CONFIG_LED_STATUS_GPIO
1df7bbba
IG
1845 The status LED can be connected to a GPIO pin.
1846 In such cases, the gpio_led driver can be used as a
79267edd 1847 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
1df7bbba
IG
1848 to include the gpio_led driver in the U-Boot binary.
1849
9dfdcdfe
IG
1850 CONFIG_GPIO_LED_INVERTED_TABLE
1851 Some GPIO connected LEDs may have inverted polarity in which
1852 case the GPIO high value corresponds to LED off state and
1853 GPIO low value corresponds to LED on state.
1854 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1855 with a list of GPIO LEDs that have inverted polarity.
1856
3f4978c7
HS
1857- I2C Support: CONFIG_SYS_I2C
1858
1859 This enable the NEW i2c subsystem, and will allow you to use
1860 i2c commands at the u-boot command line (as long as you set
1861 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1862 based realtime clock chips or other i2c devices. See
1863 common/cmd_i2c.c for a description of the command line
1864 interface.
1865
1866 ported i2c driver to the new framework:
ea818dbb
HS
1867 - drivers/i2c/soft_i2c.c:
1868 - activate first bus with CONFIG_SYS_I2C_SOFT define
1869 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1870 for defining speed and slave address
1871 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1872 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1873 for defining speed and slave address
1874 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1875 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1876 for defining speed and slave address
1877 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1878 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1879 for defining speed and slave address
3f4978c7 1880
00f792e0
HS
1881 - drivers/i2c/fsl_i2c.c:
1882 - activate i2c driver with CONFIG_SYS_I2C_FSL
1883 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1884 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1885 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1886 bus.
93e14596 1887 - If your board supports a second fsl i2c bus, define
00f792e0
HS
1888 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1889 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1890 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1891 second bus.
1892
1f2ba722 1893 - drivers/i2c/tegra_i2c.c:
10cee516
NI
1894 - activate this driver with CONFIG_SYS_I2C_TEGRA
1895 - This driver adds 4 i2c buses with a fix speed from
1896 100000 and the slave addr 0!
1f2ba722 1897
880540de
DE
1898 - drivers/i2c/ppc4xx_i2c.c
1899 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1900 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1901 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1902
fac96408 1903 - drivers/i2c/i2c_mxc.c
1904 - activate this driver with CONFIG_SYS_I2C_MXC
03544c66
AA
1905 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
1906 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
1907 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
1908 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
fac96408 1909 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1910 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1911 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1912 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1913 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1914 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
03544c66
AA
1915 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
1916 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
b445bbb4 1917 If those defines are not set, default value is 100000
fac96408 1918 for speed, and 0 for slave.
1919
1086bfa9
NI
1920 - drivers/i2c/rcar_i2c.c:
1921 - activate this driver with CONFIG_SYS_I2C_RCAR
1922 - This driver adds 4 i2c buses
1923
1924 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
1925 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
1926 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
1927 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
1928 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
1929 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
1930 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
1931 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
1932 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
1933
2035d77d
NI
1934 - drivers/i2c/sh_i2c.c:
1935 - activate this driver with CONFIG_SYS_I2C_SH
1936 - This driver adds from 2 to 5 i2c buses
1937
1938 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
1939 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
1940 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
1941 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
1942 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
1943 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
1944 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
1945 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
1946 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
1947 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
b445bbb4 1948 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
2035d77d 1949
6789e84e
HS
1950 - drivers/i2c/omap24xx_i2c.c
1951 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
1952 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
1953 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
1954 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
1955 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
1956 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
1957 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
1958 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
1959 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
1960 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
1961 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
1962
0bdffe71
HS
1963 - drivers/i2c/zynq_i2c.c
1964 - activate this driver with CONFIG_SYS_I2C_ZYNQ
1965 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
1966 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
1967
e717fc6d
NKC
1968 - drivers/i2c/s3c24x0_i2c.c:
1969 - activate this driver with CONFIG_SYS_I2C_S3C24X0
1970 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1971 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1972 with a fix speed from 100000 and the slave addr 0!
1973
b46226bd
DE
1974 - drivers/i2c/ihs_i2c.c
1975 - activate this driver with CONFIG_SYS_I2C_IHS
1976 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1977 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1978 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1979 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1980 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1981 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1982 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1983 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1984 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1985 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1986 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1987 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
071be896
DE
1988 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1989 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1990 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1991 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1992 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1993 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1994 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1995 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1996 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
b46226bd 1997
3f4978c7
HS
1998 additional defines:
1999
2000 CONFIG_SYS_NUM_I2C_BUSES
945a18e6 2001 Hold the number of i2c buses you want to use.
3f4978c7
HS
2002
2003 CONFIG_SYS_I2C_DIRECT_BUS
2004 define this, if you don't use i2c muxes on your hardware.
2005 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2006 omit this define.
2007
2008 CONFIG_SYS_I2C_MAX_HOPS
2009 define how many muxes are maximal consecutively connected
2010 on one i2c bus. If you not use i2c muxes, omit this
2011 define.
2012
2013 CONFIG_SYS_I2C_BUSES
b445bbb4 2014 hold a list of buses you want to use, only used if
3f4978c7
HS
2015 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2016 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2017 CONFIG_SYS_NUM_I2C_BUSES = 9:
2018
2019 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2020 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2021 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2022 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2023 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2024 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2025 {1, {I2C_NULL_HOP}}, \
2026 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2027 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2028 }
2029
2030 which defines
2031 bus 0 on adapter 0 without a mux
ea818dbb
HS
2032 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2033 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2034 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2035 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2036 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
3f4978c7 2037 bus 6 on adapter 1 without a mux
ea818dbb
HS
2038 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2039 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
3f4978c7
HS
2040
2041 If you do not have i2c muxes on your board, omit this define.
2042
ce3b5d69 2043- Legacy I2C Support:
ea818dbb 2044 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
b37c7e5e
WD
2045 then the following macros need to be defined (examples are
2046 from include/configs/lwmon.h):
c609719b
WD
2047
2048 I2C_INIT
2049
b37c7e5e 2050 (Optional). Any commands necessary to enable the I2C
43d9616c 2051 controller or configure ports.
c609719b 2052
ba56f625 2053 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
b37c7e5e 2054
c609719b
WD
2055 I2C_ACTIVE
2056
2057 The code necessary to make the I2C data line active
2058 (driven). If the data line is open collector, this
2059 define can be null.
2060
b37c7e5e
WD
2061 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2062
c609719b
WD
2063 I2C_TRISTATE
2064
2065 The code necessary to make the I2C data line tri-stated
2066 (inactive). If the data line is open collector, this
2067 define can be null.
2068
b37c7e5e
WD
2069 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2070
c609719b
WD
2071 I2C_READ
2072
472d5460
YS
2073 Code that returns true if the I2C data line is high,
2074 false if it is low.
c609719b 2075
b37c7e5e
WD
2076 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2077
c609719b
WD
2078 I2C_SDA(bit)
2079
472d5460
YS
2080 If <bit> is true, sets the I2C data line high. If it
2081 is false, it clears it (low).
c609719b 2082
b37c7e5e 2083 eg: #define I2C_SDA(bit) \
2535d602 2084 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
ba56f625 2085 else immr->im_cpm.cp_pbdat &= ~PB_SDA
b37c7e5e 2086
c609719b
WD
2087 I2C_SCL(bit)
2088
472d5460
YS
2089 If <bit> is true, sets the I2C clock line high. If it
2090 is false, it clears it (low).
c609719b 2091
b37c7e5e 2092 eg: #define I2C_SCL(bit) \
2535d602 2093 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
ba56f625 2094 else immr->im_cpm.cp_pbdat &= ~PB_SCL
b37c7e5e 2095
c609719b
WD
2096 I2C_DELAY
2097
2098 This delay is invoked four times per clock cycle so this
2099 controls the rate of data transfer. The data rate thus
b37c7e5e 2100 is 1 / (I2C_DELAY * 4). Often defined to be something
945af8d7
WD
2101 like:
2102
b37c7e5e 2103 #define I2C_DELAY udelay(2)
c609719b 2104
793b5726
MF
2105 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2106
2107 If your arch supports the generic GPIO framework (asm/gpio.h),
2108 then you may alternatively define the two GPIOs that are to be
2109 used as SCL / SDA. Any of the previous I2C_xxx macros will
2110 have GPIO-based defaults assigned to them as appropriate.
2111
2112 You should define these to the GPIO value as given directly to
2113 the generic GPIO functions.
2114
6d0f6bcf 2115 CONFIG_SYS_I2C_INIT_BOARD
47cd00fa 2116
8bde7f77
WD
2117 When a board is reset during an i2c bus transfer
2118 chips might think that the current transfer is still
2119 in progress. On some boards it is possible to access
2120 the i2c SCLK line directly, either by using the
2121 processor pin as a GPIO or by having a second pin
2122 connected to the bus. If this option is defined a
2123 custom i2c_init_board() routine in boards/xxx/board.c
2124 is run early in the boot sequence.
47cd00fa 2125
bb99ad6d
BW
2126 CONFIG_I2C_MULTI_BUS
2127
2128 This option allows the use of multiple I2C buses, each of which
c0f40859
WD
2129 must have a controller. At any point in time, only one bus is
2130 active. To switch to a different bus, use the 'i2c dev' command.
bb99ad6d
BW
2131 Note that bus numbering is zero-based.
2132
6d0f6bcf 2133 CONFIG_SYS_I2C_NOPROBES
bb99ad6d
BW
2134
2135 This option specifies a list of I2C devices that will be skipped
c0f40859 2136 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
0f89c54b
PT
2137 is set, specify a list of bus-device pairs. Otherwise, specify
2138 a 1D array of device addresses
bb99ad6d
BW
2139
2140 e.g.
2141 #undef CONFIG_I2C_MULTI_BUS
c0f40859 2142 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
bb99ad6d
BW
2143
2144 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2145
c0f40859 2146 #define CONFIG_I2C_MULTI_BUS
945a18e6 2147 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
bb99ad6d
BW
2148
2149 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2150
6d0f6bcf 2151 CONFIG_SYS_SPD_BUS_NUM
be5e6181
TT
2152
2153 If defined, then this indicates the I2C bus number for DDR SPD.
2154 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2155
6d0f6bcf 2156 CONFIG_SYS_RTC_BUS_NUM
0dc018ec
SR
2157
2158 If defined, then this indicates the I2C bus number for the RTC.
2159 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2160
2ac6985a
AD
2161 CONFIG_SOFT_I2C_READ_REPEATED_START
2162
2163 defining this will force the i2c_read() function in
2164 the soft_i2c driver to perform an I2C repeated start
2165 between writing the address pointer and reading the
2166 data. If this define is omitted the default behaviour
2167 of doing a stop-start sequence will be used. Most I2C
2168 devices can use either method, but some require one or
2169 the other.
be5e6181 2170
c609719b
WD
2171- SPI Support: CONFIG_SPI
2172
2173 Enables SPI driver (so far only tested with
2174 SPI EEPROM, also an instance works with Crystal A/D and
2175 D/As on the SACSng board)
2176
6639562e
YS
2177 CONFIG_SH_SPI
2178
2179 Enables the driver for SPI controller on SuperH. Currently
2180 only SH7757 is supported.
2181
c609719b
WD
2182 CONFIG_SOFT_SPI
2183
43d9616c
WD
2184 Enables a software (bit-bang) SPI driver rather than
2185 using hardware support. This is a general purpose
2186 driver that only requires three general I/O port pins
2187 (two outputs, one input) to function. If this is
2188 defined, the board configuration must define several
2189 SPI configuration items (port pins to use, etc). For
2190 an example, see include/configs/sacsng.h.
c609719b 2191
04a9e118
BW
2192 CONFIG_HARD_SPI
2193
2194 Enables a hardware SPI driver for general-purpose reads
2195 and writes. As with CONFIG_SOFT_SPI, the board configuration
2196 must define a list of chip-select function pointers.
c0f40859 2197 Currently supported on some MPC8xxx processors. For an
04a9e118
BW
2198 example, see include/configs/mpc8349emds.h.
2199
38254f45
GL
2200 CONFIG_MXC_SPI
2201
2202 Enables the driver for the SPI controllers on i.MX and MXC
2e3cd1cd 2203 SoCs. Currently i.MX31/35/51 are supported.
38254f45 2204
f659b573
HS
2205 CONFIG_SYS_SPI_MXC_WAIT
2206 Timeout for waiting until spi transfer completed.
2207 default: (CONFIG_SYS_HZ/100) /* 10 ms */
2208
0133502e 2209- FPGA Support: CONFIG_FPGA
c609719b 2210
0133502e
MF
2211 Enables FPGA subsystem.
2212
2213 CONFIG_FPGA_<vendor>
2214
2215 Enables support for specific chip vendors.
2216 (ALTERA, XILINX)
c609719b 2217
0133502e 2218 CONFIG_FPGA_<family>
c609719b 2219
0133502e
MF
2220 Enables support for FPGA family.
2221 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2222
2223 CONFIG_FPGA_COUNT
2224
2225 Specify the number of FPGA devices to support.
c609719b 2226
6d0f6bcf 2227 CONFIG_SYS_FPGA_PROG_FEEDBACK
c609719b 2228
8bde7f77 2229 Enable printing of hash marks during FPGA configuration.
c609719b 2230
6d0f6bcf 2231 CONFIG_SYS_FPGA_CHECK_BUSY
c609719b 2232
43d9616c
WD
2233 Enable checks on FPGA configuration interface busy
2234 status by the configuration function. This option
2235 will require a board or device specific function to
2236 be written.
c609719b
WD
2237
2238 CONFIG_FPGA_DELAY
2239
2240 If defined, a function that provides delays in the FPGA
2241 configuration driver.
2242
6d0f6bcf 2243 CONFIG_SYS_FPGA_CHECK_CTRLC
c609719b
WD
2244 Allow Control-C to interrupt FPGA configuration
2245
6d0f6bcf 2246 CONFIG_SYS_FPGA_CHECK_ERROR
c609719b 2247
43d9616c
WD
2248 Check for configuration errors during FPGA bitfile
2249 loading. For example, abort during Virtex II
2250 configuration if the INIT_B line goes low (which
2251 indicated a CRC error).
c609719b 2252
6d0f6bcf 2253 CONFIG_SYS_FPGA_WAIT_INIT
c609719b 2254
b445bbb4
JM
2255 Maximum time to wait for the INIT_B line to de-assert
2256 after PROB_B has been de-asserted during a Virtex II
43d9616c 2257 FPGA configuration sequence. The default time is 500
11ccc33f 2258 ms.
c609719b 2259
6d0f6bcf 2260 CONFIG_SYS_FPGA_WAIT_BUSY
c609719b 2261
b445bbb4 2262 Maximum time to wait for BUSY to de-assert during
11ccc33f 2263 Virtex II FPGA configuration. The default is 5 ms.
c609719b 2264
6d0f6bcf 2265 CONFIG_SYS_FPGA_WAIT_CONFIG
c609719b 2266
43d9616c 2267 Time to wait after FPGA configuration. The default is
11ccc33f 2268 200 ms.
c609719b
WD
2269
2270- Configuration Management:
b2b8a696
SR
2271 CONFIG_BUILD_TARGET
2272
2273 Some SoCs need special image types (e.g. U-Boot binary
2274 with a special header) as build targets. By defining
2275 CONFIG_BUILD_TARGET in the SoC / board header, this
2276 special image will be automatically built upon calling
6de80f21 2277 make / buildman.
b2b8a696 2278
c609719b
WD
2279 CONFIG_IDENT_STRING
2280
43d9616c
WD
2281 If defined, this string will be added to the U-Boot
2282 version information (U_BOOT_VERSION)
c609719b
WD
2283
2284- Vendor Parameter Protection:
2285
43d9616c
WD
2286 U-Boot considers the values of the environment
2287 variables "serial#" (Board Serial Number) and
7152b1d0 2288 "ethaddr" (Ethernet Address) to be parameters that
43d9616c
WD
2289 are set once by the board vendor / manufacturer, and
2290 protects these variables from casual modification by
2291 the user. Once set, these variables are read-only,
2292 and write or delete attempts are rejected. You can
11ccc33f 2293 change this behaviour:
c609719b
WD
2294
2295 If CONFIG_ENV_OVERWRITE is #defined in your config
2296 file, the write protection for vendor parameters is
47cd00fa 2297 completely disabled. Anybody can change or delete
c609719b
WD
2298 these parameters.
2299
92ac5208
JH
2300 Alternatively, if you define _both_ an ethaddr in the
2301 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
11ccc33f 2302 Ethernet address is installed in the environment,
c609719b
WD
2303 which can be changed exactly ONCE by the user. [The
2304 serial# is unaffected by this, i. e. it remains
2305 read-only.]
2306
2598090b
JH
2307 The same can be accomplished in a more flexible way
2308 for any variable by configuring the type of access
2309 to allow for those variables in the ".flags" variable
2310 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2311
c609719b
WD
2312- Protected RAM:
2313 CONFIG_PRAM
2314
2315 Define this variable to enable the reservation of
2316 "protected RAM", i. e. RAM which is not overwritten
2317 by U-Boot. Define CONFIG_PRAM to hold the number of
2318 kB you want to reserve for pRAM. You can overwrite
2319 this default value by defining an environment
2320 variable "pram" to the number of kB you want to
2321 reserve. Note that the board info structure will
2322 still show the full amount of RAM. If pRAM is
2323 reserved, a new environment variable "mem" will
2324 automatically be defined to hold the amount of
2325 remaining RAM in a form that can be passed as boot
2326 argument to Linux, for instance like that:
2327
fe126d8b 2328 setenv bootargs ... mem=\${mem}
c609719b
WD
2329 saveenv
2330
2331 This way you can tell Linux not to use this memory,
2332 either, which results in a memory region that will
2333 not be affected by reboots.
2334
2335 *WARNING* If your board configuration uses automatic
2336 detection of the RAM size, you must make sure that
2337 this memory test is non-destructive. So far, the
2338 following board configurations are known to be
2339 "pRAM-clean":
2340
5b8e76c3 2341 IVMS8, IVML24, SPD8xx,
1b0757ec 2342 HERMES, IP860, RPXlite, LWMON,
2eb48ff7 2343 FLAGADM
c609719b 2344
40fef049
GB
2345- Access to physical memory region (> 4GB)
2346 Some basic support is provided for operations on memory not
2347 normally accessible to U-Boot - e.g. some architectures
2348 support access to more than 4GB of memory on 32-bit
2349 machines using physical address extension or similar.
2350 Define CONFIG_PHYSMEM to access this basic support, which
2351 currently only supports clearing the memory.
2352
c609719b
WD
2353- Error Recovery:
2354 CONFIG_PANIC_HANG
2355
2356 Define this variable to stop the system in case of a
2357 fatal error, so that you have to reset it manually.
2358 This is probably NOT a good idea for an embedded
11ccc33f 2359 system where you want the system to reboot
c609719b
WD
2360 automatically as fast as possible, but it may be
2361 useful during development since you can try to debug
2362 the conditions that lead to the situation.
2363
2364 CONFIG_NET_RETRY_COUNT
2365
43d9616c
WD
2366 This variable defines the number of retries for
2367 network operations like ARP, RARP, TFTP, or BOOTP
2368 before giving up the operation. If not defined, a
2369 default value of 5 is used.
c609719b 2370
40cb90ee
GL
2371 CONFIG_ARP_TIMEOUT
2372
2373 Timeout waiting for an ARP reply in milliseconds.
2374
48a3e999
TK
2375 CONFIG_NFS_TIMEOUT
2376
2377 Timeout in milliseconds used in NFS protocol.
2378 If you encounter "ERROR: Cannot umount" in nfs command,
2379 try longer timeout such as
2380 #define CONFIG_NFS_TIMEOUT 10000UL
2381
c609719b 2382- Command Interpreter:
8078f1a5 2383 CONFIG_AUTO_COMPLETE
04a85b3b
WD
2384
2385 Enable auto completion of commands using TAB.
2386
6d0f6bcf 2387 CONFIG_SYS_PROMPT_HUSH_PS2
c609719b
WD
2388
2389 This defines the secondary prompt string, which is
2390 printed when the command interpreter needs more input
2391 to complete a command. Usually "> ".
2392
2393 Note:
2394
8bde7f77
WD
2395 In the current implementation, the local variables
2396 space and global environment variables space are
2397 separated. Local variables are those you define by
2398 simply typing `name=value'. To access a local
2399 variable later on, you have write `$name' or
2400 `${name}'; to execute the contents of a variable
2401 directly type `$name' at the command prompt.
c609719b 2402
43d9616c
WD
2403 Global environment variables are those you use
2404 setenv/printenv to work with. To run a command stored
2405 in such a variable, you need to use the run command,
2406 and you must not use the '$' sign to access them.
c609719b
WD
2407
2408 To store commands and special characters in a
2409 variable, please use double quotation marks
2410 surrounding the whole text of the variable, instead
2411 of the backslashes before semicolons and special
2412 symbols.
2413
b445bbb4 2414- Command Line Editing and History:
aa0c71ac
WD
2415 CONFIG_CMDLINE_EDITING
2416
11ccc33f 2417 Enable editing and History functions for interactive
b445bbb4 2418 command line input operations
aa0c71ac 2419
f3b267b3
MV
2420- Command Line PS1/PS2 support:
2421 CONFIG_CMDLINE_PS_SUPPORT
2422
2423 Enable support for changing the command prompt string
2424 at run-time. Only static string is supported so far.
2425 The string is obtained from environment variables PS1
2426 and PS2.
2427
a8c7c708 2428- Default Environment:
c609719b
WD
2429 CONFIG_EXTRA_ENV_SETTINGS
2430
43d9616c
WD
2431 Define this to contain any number of null terminated
2432 strings (variable = value pairs) that will be part of
7152b1d0 2433 the default environment compiled into the boot image.
2262cfee 2434
43d9616c
WD
2435 For example, place something like this in your
2436 board's config file:
c609719b
WD
2437
2438 #define CONFIG_EXTRA_ENV_SETTINGS \
2439 "myvar1=value1\0" \
2440 "myvar2=value2\0"
2441
43d9616c
WD
2442 Warning: This method is based on knowledge about the
2443 internal format how the environment is stored by the
2444 U-Boot code. This is NOT an official, exported
2445 interface! Although it is unlikely that this format
7152b1d0 2446 will change soon, there is no guarantee either.
c609719b
WD
2447 You better know what you are doing here.
2448
43d9616c
WD
2449 Note: overly (ab)use of the default environment is
2450 discouraged. Make sure to check other ways to preset
74de7aef 2451 the environment like the "source" command or the
43d9616c 2452 boot command first.
c609719b 2453
5e724ca2
SW
2454 CONFIG_ENV_VARS_UBOOT_CONFIG
2455
2456 Define this in order to add variables describing the
2457 U-Boot build configuration to the default environment.
2458 These will be named arch, cpu, board, vendor, and soc.
2459
2460 Enabling this option will cause the following to be defined:
2461
2462 - CONFIG_SYS_ARCH
2463 - CONFIG_SYS_CPU
2464 - CONFIG_SYS_BOARD
2465 - CONFIG_SYS_VENDOR
2466 - CONFIG_SYS_SOC
2467
7e27f89f
TR
2468 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2469
2470 Define this in order to add variables describing certain
2471 run-time determined information about the hardware to the
2472 environment. These will be named board_name, board_rev.
2473
06fd8538
SG
2474 CONFIG_DELAY_ENVIRONMENT
2475
2476 Normally the environment is loaded when the board is
b445bbb4 2477 initialised so that it is available to U-Boot. This inhibits
06fd8538
SG
2478 that so that the environment is not available until
2479 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2480 this is instead controlled by the value of
2481 /config/load-environment.
2482
a8c7c708 2483- DataFlash Support:
2abbe075
WD
2484 CONFIG_HAS_DATAFLASH
2485
8bde7f77
WD
2486 Defining this option enables DataFlash features and
2487 allows to read/write in Dataflash via the standard
2488 commands cp, md...
2abbe075 2489
f61ec45e
EN
2490- Serial Flash support
2491 CONFIG_CMD_SF
2492
2493 Defining this option enables SPI flash commands
2494 'sf probe/read/write/erase/update'.
2495
2496 Usage requires an initial 'probe' to define the serial
2497 flash parameters, followed by read/write/erase/update
2498 commands.
2499
2500 The following defaults may be provided by the platform
2501 to handle the common case when only a single serial
2502 flash is present on the system.
2503
2504 CONFIG_SF_DEFAULT_BUS Bus identifier
2505 CONFIG_SF_DEFAULT_CS Chip-select
2506 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2507 CONFIG_SF_DEFAULT_SPEED in Hz
2508
24007273
SG
2509 CONFIG_CMD_SF_TEST
2510
2511 Define this option to include a destructive SPI flash
2512 test ('sf test').
2513
3f85ce27
WD
2514- SystemACE Support:
2515 CONFIG_SYSTEMACE
2516
2517 Adding this option adds support for Xilinx SystemACE
2518 chips attached via some sort of local bus. The address
11ccc33f 2519 of the chip must also be defined in the
6d0f6bcf 2520 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
3f85ce27
WD
2521
2522 #define CONFIG_SYSTEMACE
6d0f6bcf 2523 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
3f85ce27
WD
2524
2525 When SystemACE support is added, the "ace" device type
2526 becomes available to the fat commands, i.e. fatls.
2527
ecb0ccd9
WD
2528- TFTP Fixed UDP Port:
2529 CONFIG_TFTP_PORT
2530
28cb9375 2531 If this is defined, the environment variable tftpsrcp
ecb0ccd9 2532 is used to supply the TFTP UDP source port value.
28cb9375 2533 If tftpsrcp isn't defined, the normal pseudo-random port
ecb0ccd9
WD
2534 number generator is used.
2535
28cb9375
WD
2536 Also, the environment variable tftpdstp is used to supply
2537 the TFTP UDP destination port value. If tftpdstp isn't
2538 defined, the normal port 69 is used.
2539
2540 The purpose for tftpsrcp is to allow a TFTP server to
ecb0ccd9
WD
2541 blindly start the TFTP transfer using the pre-configured
2542 target IP address and UDP port. This has the effect of
2543 "punching through" the (Windows XP) firewall, allowing
2544 the remainder of the TFTP transfer to proceed normally.
2545 A better solution is to properly configure the firewall,
2546 but sometimes that is not allowed.
2547
9e50c406
HS
2548- bootcount support:
2549 CONFIG_BOOTCOUNT_LIMIT
2550
2551 This enables the bootcounter support, see:
2552 http://www.denx.de/wiki/DULG/UBootBootCountLimit
2553
2554 CONFIG_AT91SAM9XE
2555 enable special bootcounter support on at91sam9xe based boards.
9e50c406
HS
2556 CONFIG_SOC_DA8XX
2557 enable special bootcounter support on da850 based boards.
2558 CONFIG_BOOTCOUNT_RAM
2559 enable support for the bootcounter in RAM
2560 CONFIG_BOOTCOUNT_I2C
2561 enable support for the bootcounter on an i2c (like RTC) device.
2562 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
2563 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
2564 the bootcounter.
2565 CONFIG_BOOTCOUNT_ALEN = address len
19c402af 2566
a8c7c708 2567- Show boot progress:
c609719b
WD
2568 CONFIG_SHOW_BOOT_PROGRESS
2569
43d9616c
WD
2570 Defining this option allows to add some board-
2571 specific code (calling a user-provided function
2572 "show_boot_progress(int)") that enables you to show
2573 the system's boot progress on some display (for
2574 example, some LED's) on your board. At the moment,
2575 the following checkpoints are implemented:
c609719b 2576
94fd1316 2577
1372cce2
MB
2578Legacy uImage format:
2579
c609719b
WD
2580 Arg Where When
2581 1 common/cmd_bootm.c before attempting to boot an image
ba56f625 2582 -1 common/cmd_bootm.c Image header has bad magic number
c609719b 2583 2 common/cmd_bootm.c Image header has correct magic number
ba56f625 2584 -2 common/cmd_bootm.c Image header has bad checksum
c609719b 2585 3 common/cmd_bootm.c Image header has correct checksum
ba56f625 2586 -3 common/cmd_bootm.c Image data has bad checksum
c609719b
WD
2587 4 common/cmd_bootm.c Image data has correct checksum
2588 -4 common/cmd_bootm.c Image is for unsupported architecture
2589 5 common/cmd_bootm.c Architecture check OK
1372cce2 2590 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
c609719b
WD
2591 6 common/cmd_bootm.c Image Type check OK
2592 -6 common/cmd_bootm.c gunzip uncompression error
2593 -7 common/cmd_bootm.c Unimplemented compression type
2594 7 common/cmd_bootm.c Uncompression OK
1372cce2 2595 8 common/cmd_bootm.c No uncompress/copy overwrite error
c609719b 2596 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1372cce2
MB
2597
2598 9 common/image.c Start initial ramdisk verification
2599 -10 common/image.c Ramdisk header has bad magic number
2600 -11 common/image.c Ramdisk header has bad checksum
2601 10 common/image.c Ramdisk header is OK
2602 -12 common/image.c Ramdisk data has bad checksum
2603 11 common/image.c Ramdisk data has correct checksum
2604 12 common/image.c Ramdisk verification complete, start loading
11ccc33f 2605 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
1372cce2
MB
2606 13 common/image.c Start multifile image verification
2607 14 common/image.c No initial ramdisk, no multifile, continue.
2608
c0f40859 2609 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
c609719b 2610
a47a12be 2611 -30 arch/powerpc/lib/board.c Fatal error, hang the system
11dadd54
WD
2612 -31 post/post.c POST test failed, detected by post_output_backlog()
2613 -32 post/post.c POST test failed, detected by post_run_single()
63e73c9a 2614
566a494f
HS
2615 34 common/cmd_doc.c before loading a Image from a DOC device
2616 -35 common/cmd_doc.c Bad usage of "doc" command
2617 35 common/cmd_doc.c correct usage of "doc" command
2618 -36 common/cmd_doc.c No boot device
2619 36 common/cmd_doc.c correct boot device
2620 -37 common/cmd_doc.c Unknown Chip ID on boot device
2621 37 common/cmd_doc.c correct chip ID found, device available
2622 -38 common/cmd_doc.c Read Error on boot device
2623 38 common/cmd_doc.c reading Image header from DOC device OK
2624 -39 common/cmd_doc.c Image header has bad magic number
2625 39 common/cmd_doc.c Image header has correct magic number
2626 -40 common/cmd_doc.c Error reading Image from DOC device
2627 40 common/cmd_doc.c Image header has correct magic number
2628 41 common/cmd_ide.c before loading a Image from a IDE device
2629 -42 common/cmd_ide.c Bad usage of "ide" command
2630 42 common/cmd_ide.c correct usage of "ide" command
2631 -43 common/cmd_ide.c No boot device
2632 43 common/cmd_ide.c boot device found
2633 -44 common/cmd_ide.c Device not available
2634 44 common/cmd_ide.c Device available
2635 -45 common/cmd_ide.c wrong partition selected
2636 45 common/cmd_ide.c partition selected
2637 -46 common/cmd_ide.c Unknown partition table
2638 46 common/cmd_ide.c valid partition table found
2639 -47 common/cmd_ide.c Invalid partition type
2640 47 common/cmd_ide.c correct partition type
2641 -48 common/cmd_ide.c Error reading Image Header on boot device
2642 48 common/cmd_ide.c reading Image Header from IDE device OK
2643 -49 common/cmd_ide.c Image header has bad magic number
2644 49 common/cmd_ide.c Image header has correct magic number
2645 -50 common/cmd_ide.c Image header has bad checksum
2646 50 common/cmd_ide.c Image header has correct checksum
2647 -51 common/cmd_ide.c Error reading Image from IDE device
2648 51 common/cmd_ide.c reading Image from IDE device OK
2649 52 common/cmd_nand.c before loading a Image from a NAND device
2650 -53 common/cmd_nand.c Bad usage of "nand" command
2651 53 common/cmd_nand.c correct usage of "nand" command
2652 -54 common/cmd_nand.c No boot device
2653 54 common/cmd_nand.c boot device found
2654 -55 common/cmd_nand.c Unknown Chip ID on boot device
2655 55 common/cmd_nand.c correct chip ID found, device available
2656 -56 common/cmd_nand.c Error reading Image Header on boot device
2657 56 common/cmd_nand.c reading Image Header from NAND device OK
2658 -57 common/cmd_nand.c Image header has bad magic number
2659 57 common/cmd_nand.c Image header has correct magic number
2660 -58 common/cmd_nand.c Error reading Image from NAND device
2661 58 common/cmd_nand.c reading Image from NAND device OK
2662
2663 -60 common/env_common.c Environment has a bad CRC, using default
2664
11ccc33f 2665 64 net/eth.c starting with Ethernet configuration.
566a494f
HS
2666 -64 net/eth.c no Ethernet found.
2667 65 net/eth.c Ethernet found.
2668
2669 -80 common/cmd_net.c usage wrong
bc0571fc
JH
2670 80 common/cmd_net.c before calling net_loop()
2671 -81 common/cmd_net.c some error in net_loop() occurred
2672 81 common/cmd_net.c net_loop() back without error
566a494f
HS
2673 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2674 82 common/cmd_net.c trying automatic boot
74de7aef
WD
2675 83 common/cmd_net.c running "source" command
2676 -83 common/cmd_net.c some error in automatic boot or "source" command
566a494f 2677 84 common/cmd_net.c end without errors
c609719b 2678
1372cce2
MB
2679FIT uImage format:
2680
2681 Arg Where When
2682 100 common/cmd_bootm.c Kernel FIT Image has correct format
2683 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2684 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2685 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2686 102 common/cmd_bootm.c Kernel unit name specified
2687 -103 common/cmd_bootm.c Can't get kernel subimage node offset
f773bea8 2688 103 common/cmd_bootm.c Found configuration node
1372cce2
MB
2689 104 common/cmd_bootm.c Got kernel subimage node offset
2690 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2691 105 common/cmd_bootm.c Kernel subimage hash verification OK
2692 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2693 106 common/cmd_bootm.c Architecture check OK
11ccc33f
MZ
2694 -106 common/cmd_bootm.c Kernel subimage has wrong type
2695 107 common/cmd_bootm.c Kernel subimage type OK
1372cce2
MB
2696 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2697 108 common/cmd_bootm.c Got kernel subimage data/size
2698 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2699 -109 common/cmd_bootm.c Can't get kernel subimage type
2700 -110 common/cmd_bootm.c Can't get kernel subimage comp
2701 -111 common/cmd_bootm.c Can't get kernel subimage os
2702 -112 common/cmd_bootm.c Can't get kernel subimage load address
2703 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2704
2705 120 common/image.c Start initial ramdisk verification
2706 -120 common/image.c Ramdisk FIT image has incorrect format
2707 121 common/image.c Ramdisk FIT image has correct format
11ccc33f 2708 122 common/image.c No ramdisk subimage unit name, using configuration
1372cce2
MB
2709 -122 common/image.c Can't get configuration for ramdisk subimage
2710 123 common/image.c Ramdisk unit name specified
2711 -124 common/image.c Can't get ramdisk subimage node offset
2712 125 common/image.c Got ramdisk subimage node offset
2713 -125 common/image.c Ramdisk subimage hash verification failed
2714 126 common/image.c Ramdisk subimage hash verification OK
2715 -126 common/image.c Ramdisk subimage for unsupported architecture
2716 127 common/image.c Architecture check OK
2717 -127 common/image.c Can't get ramdisk subimage data/size
2718 128 common/image.c Got ramdisk subimage data/size
2719 129 common/image.c Can't get ramdisk load address
2720 -129 common/image.c Got ramdisk load address
2721
11ccc33f 2722 -130 common/cmd_doc.c Incorrect FIT image format
1372cce2
MB
2723 131 common/cmd_doc.c FIT image format OK
2724
11ccc33f 2725 -140 common/cmd_ide.c Incorrect FIT image format
1372cce2
MB
2726 141 common/cmd_ide.c FIT image format OK
2727
11ccc33f 2728 -150 common/cmd_nand.c Incorrect FIT image format
1372cce2
MB
2729 151 common/cmd_nand.c FIT image format OK
2730
21d29f7f
HS
2731- legacy image format:
2732 CONFIG_IMAGE_FORMAT_LEGACY
2733 enables the legacy image format support in U-Boot.
2734
2735 Default:
2736 enabled if CONFIG_FIT_SIGNATURE is not defined.
2737
2738 CONFIG_DISABLE_IMAGE_LEGACY
2739 disable the legacy image format
2740
2741 This define is introduced, as the legacy image format is
2742 enabled per default for backward compatibility.
2743
4cf2609b
WD
2744- Standalone program support:
2745 CONFIG_STANDALONE_LOAD_ADDR
2746
6feff899
WD
2747 This option defines a board specific value for the
2748 address where standalone program gets loaded, thus
2749 overwriting the architecture dependent default
4cf2609b
WD
2750 settings.
2751
2752- Frame Buffer Address:
2753 CONFIG_FB_ADDR
2754
2755 Define CONFIG_FB_ADDR if you want to use specific
44a53b57
WD
2756 address for frame buffer. This is typically the case
2757 when using a graphics controller has separate video
2758 memory. U-Boot will then place the frame buffer at
2759 the given address instead of dynamically reserving it
2760 in system RAM by calling lcd_setmem(), which grabs
2761 the memory for the frame buffer depending on the
2762 configured panel size.
4cf2609b
WD
2763
2764 Please see board_init_f function.
2765
cccfc2ab
DZ
2766- Automatic software updates via TFTP server
2767 CONFIG_UPDATE_TFTP
2768 CONFIG_UPDATE_TFTP_CNT_MAX
2769 CONFIG_UPDATE_TFTP_MSEC_MAX
2770
2771 These options enable and control the auto-update feature;
2772 for a more detailed description refer to doc/README.update.
2773
2774- MTD Support (mtdparts command, UBI support)
2775 CONFIG_MTD_DEVICE
2776
2777 Adds the MTD device infrastructure from the Linux kernel.
2778 Needed for mtdparts command support.
2779
2780 CONFIG_MTD_PARTITIONS
2781
2782 Adds the MTD partitioning infrastructure from the Linux
2783 kernel. Needed for UBI support.
2784
70c219cd 2785- UBI support
147162da
JH
2786 CONFIG_UBI_SILENCE_MSG
2787
2788 Make the verbose messages from UBI stop printing. This leaves
2789 warnings and errors enabled.
2790
ff94bc40
HS
2791
2792 CONFIG_MTD_UBI_WL_THRESHOLD
2793 This parameter defines the maximum difference between the highest
2794 erase counter value and the lowest erase counter value of eraseblocks
2795 of UBI devices. When this threshold is exceeded, UBI starts performing
2796 wear leveling by means of moving data from eraseblock with low erase
2797 counter to eraseblocks with high erase counter.
2798
2799 The default value should be OK for SLC NAND flashes, NOR flashes and
2800 other flashes which have eraseblock life-cycle 100000 or more.
2801 However, in case of MLC NAND flashes which typically have eraseblock
2802 life-cycle less than 10000, the threshold should be lessened (e.g.,
2803 to 128 or 256, although it does not have to be power of 2).
2804
2805 default: 4096
c654b517 2806
ff94bc40
HS
2807 CONFIG_MTD_UBI_BEB_LIMIT
2808 This option specifies the maximum bad physical eraseblocks UBI
2809 expects on the MTD device (per 1024 eraseblocks). If the
2810 underlying flash does not admit of bad eraseblocks (e.g. NOR
2811 flash), this value is ignored.
2812
2813 NAND datasheets often specify the minimum and maximum NVM
2814 (Number of Valid Blocks) for the flashes' endurance lifetime.
2815 The maximum expected bad eraseblocks per 1024 eraseblocks
2816 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2817 which gives 20 for most NANDs (MaxNVB is basically the total
2818 count of eraseblocks on the chip).
2819
2820 To put it differently, if this value is 20, UBI will try to
2821 reserve about 1.9% of physical eraseblocks for bad blocks
2822 handling. And that will be 1.9% of eraseblocks on the entire
2823 NAND chip, not just the MTD partition UBI attaches. This means
2824 that if you have, say, a NAND flash chip admits maximum 40 bad
2825 eraseblocks, and it is split on two MTD partitions of the same
2826 size, UBI will reserve 40 eraseblocks when attaching a
2827 partition.
2828
2829 default: 20
2830
2831 CONFIG_MTD_UBI_FASTMAP
2832 Fastmap is a mechanism which allows attaching an UBI device
2833 in nearly constant time. Instead of scanning the whole MTD device it
2834 only has to locate a checkpoint (called fastmap) on the device.
2835 The on-flash fastmap contains all information needed to attach
2836 the device. Using fastmap makes only sense on large devices where
2837 attaching by scanning takes long. UBI will not automatically install
2838 a fastmap on old images, but you can set the UBI parameter
2839 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2840 that fastmap-enabled images are still usable with UBI implementations
2841 without fastmap support. On typical flash devices the whole fastmap
2842 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2843
2844 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2845 Set this parameter to enable fastmap automatically on images
2846 without a fastmap.
2847 default: 0
2848
0195a7bb
HS
2849 CONFIG_MTD_UBI_FM_DEBUG
2850 Enable UBI fastmap debug
2851 default: 0
2852
70c219cd 2853- UBIFS support
147162da
JH
2854 CONFIG_UBIFS_SILENCE_MSG
2855
2856 Make the verbose messages from UBIFS stop printing. This leaves
2857 warnings and errors enabled.
2858
6a11cf48 2859- SPL framework
04e5ae79
WD
2860 CONFIG_SPL
2861 Enable building of SPL globally.
6a11cf48 2862
95579793
TR
2863 CONFIG_SPL_LDSCRIPT
2864 LDSCRIPT for linking the SPL binary.
2865
6ebc3461
AA
2866 CONFIG_SPL_MAX_FOOTPRINT
2867 Maximum size in memory allocated to the SPL, BSS included.
2868 When defined, the linker checks that the actual memory
2869 used by SPL from _start to __bss_end does not exceed it.
8960af8b 2870 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
6ebc3461
AA
2871 must not be both defined at the same time.
2872
95579793 2873 CONFIG_SPL_MAX_SIZE
6ebc3461
AA
2874 Maximum size of the SPL image (text, data, rodata, and
2875 linker lists sections), BSS excluded.
2876 When defined, the linker checks that the actual size does
2877 not exceed it.
95579793 2878
04e5ae79
WD
2879 CONFIG_SPL_TEXT_BASE
2880 TEXT_BASE for linking the SPL binary.
6a11cf48 2881
94a45bb1
SW
2882 CONFIG_SPL_RELOC_TEXT_BASE
2883 Address to relocate to. If unspecified, this is equal to
2884 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2885
95579793
TR
2886 CONFIG_SPL_BSS_START_ADDR
2887 Link address for the BSS within the SPL binary.
2888
2889 CONFIG_SPL_BSS_MAX_SIZE
6ebc3461
AA
2890 Maximum size in memory allocated to the SPL BSS.
2891 When defined, the linker checks that the actual memory used
2892 by SPL from __bss_start to __bss_end does not exceed it.
8960af8b 2893 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
6ebc3461 2894 must not be both defined at the same time.
95579793
TR
2895
2896 CONFIG_SPL_STACK
2897 Adress of the start of the stack SPL will use
2898
8c80eb3b
AA
2899 CONFIG_SPL_PANIC_ON_RAW_IMAGE
2900 When defined, SPL will panic() if the image it has
2901 loaded does not have a signature.
2902 Defining this is useful when code which loads images
2903 in SPL cannot guarantee that absolutely all read errors
2904 will be caught.
2905 An example is the LPC32XX MLC NAND driver, which will
2906 consider that a completely unreadable NAND block is bad,
2907 and thus should be skipped silently.
2908
94a45bb1
SW
2909 CONFIG_SPL_RELOC_STACK
2910 Adress of the start of the stack SPL will use after
2911 relocation. If unspecified, this is equal to
2912 CONFIG_SPL_STACK.
2913
95579793
TR
2914 CONFIG_SYS_SPL_MALLOC_START
2915 Starting address of the malloc pool used in SPL.
9ac4fc82
FE
2916 When this option is set the full malloc is used in SPL and
2917 it is set up by spl_init() and before that, the simple malloc()
2918 can be used if CONFIG_SYS_MALLOC_F is defined.
95579793
TR
2919
2920 CONFIG_SYS_SPL_MALLOC_SIZE
2921 The size of the malloc pool used in SPL.
6a11cf48 2922
47f7bcae
TR
2923 CONFIG_SPL_FRAMEWORK
2924 Enable the SPL framework under common/. This framework
2925 supports MMC, NAND and YMODEM loading of U-Boot and NAND
2926 NAND loading of the Linux Kernel.
2927
9607faf2
TR
2928 CONFIG_SPL_OS_BOOT
2929 Enable booting directly to an OS from SPL.
2930 See also: doc/README.falcon
2931
861a86f4
TR
2932 CONFIG_SPL_DISPLAY_PRINT
2933 For ARM, enable an optional function to print more information
2934 about the running system.
2935
4b919725
SW
2936 CONFIG_SPL_INIT_MINIMAL
2937 Arch init code should be built for a very small image
2938
b97300b6
PK
2939 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2940 Partition on the MMC to load U-Boot from when the MMC is being
2941 used in raw mode
2942
2b75b0ad
PK
2943 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2944 Sector to load kernel uImage from when MMC is being
2945 used in raw mode (for Falcon mode)
2946
2947 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2948 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2949 Sector and number of sectors to load kernel argument
2950 parameters from when MMC is being used in raw mode
2951 (for falcon mode)
2952
e2ccdf89
PK
2953 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2954 Partition on the MMC to load U-Boot from when the MMC is being
2955 used in fs mode
2956
fae81c72
GG
2957 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2958 Filename to read to load U-Boot when reading from filesystem
2959
2960 CONFIG_SPL_FS_LOAD_KERNEL_NAME
7ad2cc79 2961 Filename to read to load kernel uImage when reading
fae81c72 2962 from filesystem (for Falcon mode)
7ad2cc79 2963
fae81c72 2964 CONFIG_SPL_FS_LOAD_ARGS_NAME
7ad2cc79 2965 Filename to read to load kernel argument parameters
fae81c72 2966 when reading from filesystem (for Falcon mode)
7ad2cc79 2967
06f60ae3
SW
2968 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
2969 Set this for NAND SPL on PPC mpc83xx targets, so that
2970 start.S waits for the rest of the SPL to load before
2971 continuing (the hardware starts execution after just
2972 loading the first page rather than the full 4K).
2973
651fcf60
PK
2974 CONFIG_SPL_SKIP_RELOCATE
2975 Avoid SPL relocation
2976
6f2f01b9
SW
2977 CONFIG_SPL_NAND_BASE
2978 Include nand_base.c in the SPL. Requires
2979 CONFIG_SPL_NAND_DRIVERS.
2980
2981 CONFIG_SPL_NAND_DRIVERS
2982 SPL uses normal NAND drivers, not minimal drivers.
2983
2984 CONFIG_SPL_NAND_ECC
2985 Include standard software ECC in the SPL
2986
95579793 2987 CONFIG_SPL_NAND_SIMPLE
7d4b7955
SW
2988 Support for NAND boot using simple NAND drivers that
2989 expose the cmd_ctrl() interface.
95579793 2990
6f4e7d3c
TG
2991 CONFIG_SPL_UBI
2992 Support for a lightweight UBI (fastmap) scanner and
2993 loader
2994
0c3117b1
HS
2995 CONFIG_SPL_NAND_RAW_ONLY
2996 Support to boot only raw u-boot.bin images. Use this only
2997 if you need to save space.
2998
7c8eea59
YZ
2999 CONFIG_SPL_COMMON_INIT_DDR
3000 Set for common ddr init with serial presence detect in
3001 SPL binary.
3002
95579793
TR
3003 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3004 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3005 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3006 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3007 CONFIG_SYS_NAND_ECCBYTES
3008 Defines the size and behavior of the NAND that SPL uses
7d4b7955 3009 to read U-Boot
95579793 3010
fbe76ae4
PK
3011 CONFIG_SPL_NAND_BOOT
3012 Add support NAND boot
3013
95579793 3014 CONFIG_SYS_NAND_U_BOOT_OFFS
7d4b7955
SW
3015 Location in NAND to read U-Boot from
3016
3017 CONFIG_SYS_NAND_U_BOOT_DST
3018 Location in memory to load U-Boot to
3019
3020 CONFIG_SYS_NAND_U_BOOT_SIZE
3021 Size of image to load
95579793
TR
3022
3023 CONFIG_SYS_NAND_U_BOOT_START
7d4b7955 3024 Entry point in loaded image to jump to
95579793
TR
3025
3026 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3027 Define this if you need to first read the OOB and then the
b445bbb4 3028 data. This is used, for example, on davinci platforms.
95579793
TR
3029
3030 CONFIG_SPL_OMAP3_ID_NAND
3031 Support for an OMAP3-specific set of functions to return the
3032 ID and MFR of the first attached NAND chip, if present.
3033
c57b953d
PM
3034 CONFIG_SPL_RAM_DEVICE
3035 Support for running image already present in ram, in SPL binary
6a11cf48 3036
74752baa 3037 CONFIG_SPL_PAD_TO
6113d3f2
BT
3038 Image offset to which the SPL should be padded before appending
3039 the SPL payload. By default, this is defined as
3040 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3041 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3042 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
74752baa 3043
ca2fca22
SW
3044 CONFIG_SPL_TARGET
3045 Final target image containing SPL and payload. Some SPLs
3046 use an arch-specific makefile fragment instead, for
3047 example if more than one image needs to be produced.
3048
87ebee39
SG
3049 CONFIG_FIT_SPL_PRINT
3050 Printing information about a FIT image adds quite a bit of
3051 code to SPL. So this is normally disabled in SPL. Use this
3052 option to re-enable it. This will affect the output of the
3053 bootm command when booting a FIT image.
3054
3aa29de0
YZ
3055- TPL framework
3056 CONFIG_TPL
3057 Enable building of TPL globally.
3058
3059 CONFIG_TPL_PAD_TO
3060 Image offset to which the TPL should be padded before appending
3061 the TPL payload. By default, this is defined as
93e14596
WD
3062 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3063 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3064 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3aa29de0 3065
a8c7c708
WD
3066- Interrupt support (PPC):
3067
d4ca31c4
WD
3068 There are common interrupt_init() and timer_interrupt()
3069 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
11ccc33f 3070 for CPU specific initialization. interrupt_init_cpu()
d4ca31c4 3071 should set decrementer_count to appropriate value. If
11ccc33f 3072 CPU resets decrementer automatically after interrupt
d4ca31c4 3073 (ppc4xx) it should set decrementer_count to zero.
11ccc33f 3074 timer_interrupt() calls timer_interrupt_cpu() for CPU
d4ca31c4
WD
3075 specific handling. If board has watchdog / status_led
3076 / other_activity_monitor it works automatically from
3077 general timer_interrupt().
a8c7c708 3078
c609719b 3079
9660e442
HR
3080Board initialization settings:
3081------------------------------
3082
3083During Initialization u-boot calls a number of board specific functions
3084to allow the preparation of board specific prerequisites, e.g. pin setup
3085before drivers are initialized. To enable these callbacks the
3086following configuration macros have to be defined. Currently this is
3087architecture specific, so please check arch/your_architecture/lib/board.c
3088typically in board_init_f() and board_init_r().
3089
3090- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3091- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3092- CONFIG_BOARD_LATE_INIT: Call board_late_init()
3093- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
c609719b 3094
c609719b
WD
3095Configuration Settings:
3096-----------------------
3097
4d1fd7f1
YS
3098- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
3099 Optionally it can be defined to support 64-bit memory commands.
3100
6d0f6bcf 3101- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
c609719b
WD
3102 undefine this when you're short of memory.
3103
2fb2604d
PT
3104- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3105 width of the commands listed in the 'help' command output.
3106
6d0f6bcf 3107- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
c609719b
WD
3108 prompt for user input.
3109
6d0f6bcf 3110- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
c609719b 3111
6d0f6bcf 3112- CONFIG_SYS_PBSIZE: Buffer size for Console output
c609719b 3113
6d0f6bcf 3114- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
c609719b 3115
6d0f6bcf 3116- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
c609719b
WD
3117 the application (usually a Linux kernel) when it is
3118 booted
3119
6d0f6bcf 3120- CONFIG_SYS_BAUDRATE_TABLE:
c609719b
WD
3121 List of legal baudrate settings for this board.
3122
6d0f6bcf 3123- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
c609719b
WD
3124 Begin and End addresses of the area used by the
3125 simple memory test.
3126
6d0f6bcf 3127- CONFIG_SYS_ALT_MEMTEST:
8bde7f77 3128 Enable an alternate, more extensive memory test.
c609719b 3129
6d0f6bcf 3130- CONFIG_SYS_MEMTEST_SCRATCH:
5f535fe1
WD
3131 Scratch address used by the alternate memory test
3132 You only need to set this if address zero isn't writeable
3133
e8149522 3134- CONFIG_SYS_MEM_RESERVE_SECURE
e61a7534 3135 Only implemented for ARMv8 for now.
e8149522
YS
3136 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
3137 is substracted from total RAM and won't be reported to OS.
3138 This memory can be used as secure memory. A variable
e61a7534 3139 gd->arch.secure_ram is used to track the location. In systems
e8149522
YS
3140 the RAM base is not zero, or RAM is divided into banks,
3141 this variable needs to be recalcuated to get the address.
3142
aabd7ddb 3143- CONFIG_SYS_MEM_TOP_HIDE:
6d0f6bcf 3144 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
14f73ca6 3145 this specified memory area will get subtracted from the top
11ccc33f 3146 (end) of RAM and won't get "touched" at all by U-Boot. By
14f73ca6
SR
3147 fixing up gd->ram_size the Linux kernel should gets passed
3148 the now "corrected" memory size and won't touch it either.
3149 This should work for arch/ppc and arch/powerpc. Only Linux
5e12e75d 3150 board ports in arch/powerpc with bootwrapper support that
14f73ca6 3151 recalculate the memory size from the SDRAM controller setup
5e12e75d 3152 will have to get fixed in Linux additionally.
14f73ca6
SR
3153
3154 This option can be used as a workaround for the 440EPx/GRx
3155 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3156 be touched.
3157
3158 WARNING: Please make sure that this value is a multiple of
3159 the Linux page size (normally 4k). If this is not the case,
3160 then the end address of the Linux memory will be located at a
3161 non page size aligned address and this could cause major
3162 problems.
3163
6d0f6bcf 3164- CONFIG_SYS_LOADS_BAUD_CHANGE:
c609719b
WD
3165 Enable temporary baudrate change while serial download
3166
6d0f6bcf 3167- CONFIG_SYS_SDRAM_BASE:
c609719b
WD
3168 Physical start address of SDRAM. _Must_ be 0 here.
3169
6d0f6bcf 3170- CONFIG_SYS_FLASH_BASE:
c609719b
WD
3171 Physical start address of Flash memory.
3172
6d0f6bcf 3173- CONFIG_SYS_MONITOR_BASE:
c609719b
WD
3174 Physical start address of boot monitor code (set by
3175 make config files to be same as the text base address
14d0a02a 3176 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
6d0f6bcf 3177 CONFIG_SYS_FLASH_BASE when booting from flash.
c609719b 3178
6d0f6bcf 3179- CONFIG_SYS_MONITOR_LEN:
8bde7f77
WD
3180 Size of memory reserved for monitor code, used to
3181 determine _at_compile_time_ (!) if the environment is
3182 embedded within the U-Boot image, or in a separate
3183 flash sector.
c609719b 3184
6d0f6bcf 3185- CONFIG_SYS_MALLOC_LEN:
c609719b
WD
3186 Size of DRAM reserved for malloc() use.
3187
d59476b6
SG
3188- CONFIG_SYS_MALLOC_F_LEN
3189 Size of the malloc() pool for use before relocation. If
3190 this is defined, then a very simple malloc() implementation
3191 will become available before relocation. The address is just
3192 below the global data, and the stack is moved down to make
3193 space.
3194
3195 This feature allocates regions with increasing addresses
3196 within the region. calloc() is supported, but realloc()
3197 is not available. free() is supported but does nothing.
b445bbb4 3198 The memory will be freed (or in fact just forgotten) when
d59476b6
SG
3199 U-Boot relocates itself.
3200
38687ae6
SG
3201- CONFIG_SYS_MALLOC_SIMPLE
3202 Provides a simple and small malloc() and calloc() for those
3203 boards which do not use the full malloc in SPL (which is
3204 enabled with CONFIG_SYS_SPL_MALLOC_START).
3205
1dfdd9ba
TR
3206- CONFIG_SYS_NONCACHED_MEMORY:
3207 Size of non-cached memory area. This area of memory will be
3208 typically located right below the malloc() area and mapped
3209 uncached in the MMU. This is useful for drivers that would
3210 otherwise require a lot of explicit cache maintenance. For
3211 some drivers it's also impossible to properly maintain the
3212 cache. For example if the regions that need to be flushed
3213 are not a multiple of the cache-line size, *and* padding
3214 cannot be allocated between the regions to align them (i.e.
3215 if the HW requires a contiguous array of regions, and the
3216 size of each region is not cache-aligned), then a flush of
3217 one region may result in overwriting data that hardware has
3218 written to another region in the same cache-line. This can
3219 happen for example in network drivers where descriptors for
3220 buffers are typically smaller than the CPU cache-line (e.g.
3221 16 bytes vs. 32 or 64 bytes).
3222
3223 Non-cached memory is only supported on 32-bit ARM at present.
3224
6d0f6bcf 3225- CONFIG_SYS_BOOTM_LEN:
15940c9a
SR
3226 Normally compressed uImages are limited to an
3227 uncompressed size of 8 MBytes. If this is not enough,
6d0f6bcf 3228 you can define CONFIG_SYS_BOOTM_LEN in your board config file
15940c9a
SR
3229 to adjust this setting to your needs.
3230
6d0f6bcf 3231- CONFIG_SYS_BOOTMAPSZ:
c609719b
WD
3232 Maximum size of memory mapped by the startup code of
3233 the Linux kernel; all data that must be processed by
7d721e34
BS
3234 the Linux kernel (bd_info, boot arguments, FDT blob if
3235 used) must be put below this limit, unless "bootm_low"
1bce2aeb 3236 environment variable is defined and non-zero. In such case
7d721e34 3237 all data for the Linux kernel must be between "bootm_low"
c0f40859 3238 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
c3624e6e
GL
3239 variable "bootm_mapsize" will override the value of
3240 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3241 then the value in "bootm_size" will be used instead.
c609719b 3242
fca43cc8
JR
3243- CONFIG_SYS_BOOT_RAMDISK_HIGH:
3244 Enable initrd_high functionality. If defined then the
3245 initrd_high feature is enabled and the bootm ramdisk subcommand
3246 is enabled.
3247
3248- CONFIG_SYS_BOOT_GET_CMDLINE:
3249 Enables allocating and saving kernel cmdline in space between
3250 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3251
3252- CONFIG_SYS_BOOT_GET_KBD:
3253 Enables allocating and saving a kernel copy of the bd_info in
3254 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3255
6d0f6bcf 3256- CONFIG_SYS_MAX_FLASH_BANKS:
c609719b
WD
3257 Max number of Flash memory banks
3258
6d0f6bcf 3259- CONFIG_SYS_MAX_FLASH_SECT:
c609719b
WD
3260 Max number of sectors on a Flash chip
3261
6d0f6bcf 3262- CONFIG_SYS_FLASH_ERASE_TOUT:
c609719b
WD
3263 Timeout for Flash erase operations (in ms)
3264
6d0f6bcf 3265- CONFIG_SYS_FLASH_WRITE_TOUT:
c609719b
WD
3266 Timeout for Flash write operations (in ms)
3267
6d0f6bcf 3268- CONFIG_SYS_FLASH_LOCK_TOUT
8564acf9
WD
3269 Timeout for Flash set sector lock bit operation (in ms)
3270
6d0f6bcf 3271- CONFIG_SYS_FLASH_UNLOCK_TOUT
8564acf9
WD
3272 Timeout for Flash clear lock bits operation (in ms)
3273
6d0f6bcf 3274- CONFIG_SYS_FLASH_PROTECTION
8564acf9
WD
3275 If defined, hardware flash sectors protection is used
3276 instead of U-Boot software protection.
3277
6d0f6bcf 3278- CONFIG_SYS_DIRECT_FLASH_TFTP:
c609719b
WD
3279
3280 Enable TFTP transfers directly to flash memory;
3281 without this option such a download has to be
3282 performed in two steps: (1) download to RAM, and (2)
3283 copy from RAM to flash.
3284
3285 The two-step approach is usually more reliable, since
3286 you can check if the download worked before you erase
11ccc33f
MZ
3287 the flash, but in some situations (when system RAM is
3288 too limited to allow for a temporary copy of the
c609719b
WD
3289 downloaded image) this option may be very useful.
3290
6d0f6bcf 3291- CONFIG_SYS_FLASH_CFI:
43d9616c 3292 Define if the flash driver uses extra elements in the
5653fc33
WD
3293 common flash structure for storing flash geometry.
3294
00b1883a 3295- CONFIG_FLASH_CFI_DRIVER
5653fc33
WD
3296 This option also enables the building of the cfi_flash driver
3297 in the drivers directory
c609719b 3298
91809ed5
PZ
3299- CONFIG_FLASH_CFI_MTD
3300 This option enables the building of the cfi_mtd driver
3301 in the drivers directory. The driver exports CFI flash
3302 to the MTD layer.
3303
6d0f6bcf 3304- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
96ef831f
GL
3305 Use buffered writes to flash.
3306
3307- CONFIG_FLASH_SPANSION_S29WS_N
3308 s29ws-n MirrorBit flash has non-standard addresses for buffered
3309 write commands.
3310
6d0f6bcf 3311- CONFIG_SYS_FLASH_QUIET_TEST
5568e613
SR
3312 If this option is defined, the common CFI flash doesn't
3313 print it's warning upon not recognized FLASH banks. This
3314 is useful, if some of the configured banks are only
3315 optionally available.
3316
9a042e9c
JVB
3317- CONFIG_FLASH_SHOW_PROGRESS
3318 If defined (must be an integer), print out countdown
3319 digits and dots. Recommended value: 45 (9..1) for 80
3320 column displays, 15 (3..1) for 40 column displays.
3321
352ef3f1
SR
3322- CONFIG_FLASH_VERIFY
3323 If defined, the content of the flash (destination) is compared
3324 against the source after the write operation. An error message
3325 will be printed when the contents are not identical.
3326 Please note that this option is useless in nearly all cases,
3327 since such flash programming errors usually are detected earlier
3328 while unprotecting/erasing/programming. Please only enable
3329 this option if you really know what you are doing.
3330
6d0f6bcf 3331- CONFIG_SYS_RX_ETH_BUFFER:
11ccc33f
MZ
3332 Defines the number of Ethernet receive buffers. On some
3333 Ethernet controllers it is recommended to set this value
53cf9435
SR
3334 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3335 buffers can be full shortly after enabling the interface
11ccc33f 3336 on high Ethernet traffic.
53cf9435
SR
3337 Defaults to 4 if not defined.
3338
ea882baf
WD
3339- CONFIG_ENV_MAX_ENTRIES
3340
071bc923
WD
3341 Maximum number of entries in the hash table that is used
3342 internally to store the environment settings. The default
3343 setting is supposed to be generous and should work in most
3344 cases. This setting can be used to tune behaviour; see
3345 lib/hashtable.c for details.
ea882baf 3346
2598090b
JH
3347- CONFIG_ENV_FLAGS_LIST_DEFAULT
3348- CONFIG_ENV_FLAGS_LIST_STATIC
1bce2aeb 3349 Enable validation of the values given to environment variables when
2598090b
JH
3350 calling env set. Variables can be restricted to only decimal,
3351 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3352 the variables can also be restricted to IP address or MAC address.
3353
3354 The format of the list is:
3355 type_attribute = [s|d|x|b|i|m]
b445bbb4
JM
3356 access_attribute = [a|r|o|c]
3357 attributes = type_attribute[access_attribute]
2598090b
JH
3358 entry = variable_name[:attributes]
3359 list = entry[,list]
3360
3361 The type attributes are:
3362 s - String (default)
3363 d - Decimal
3364 x - Hexadecimal
3365 b - Boolean ([1yYtT|0nNfF])
3366 i - IP address
3367 m - MAC address
3368
267541f7
JH
3369 The access attributes are:
3370 a - Any (default)
3371 r - Read-only
3372 o - Write-once
3373 c - Change-default
3374
2598090b
JH
3375 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3376 Define this to a list (string) to define the ".flags"
b445bbb4 3377 environment variable in the default or embedded environment.
2598090b
JH
3378
3379 - CONFIG_ENV_FLAGS_LIST_STATIC
3380 Define this to a list (string) to define validation that
3381 should be done if an entry is not found in the ".flags"
3382 environment variable. To override a setting in the static
3383 list, simply add an entry for the same variable name to the
3384 ".flags" variable.
3385
bdf1fe4e
JH
3386 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3387 regular expression. This allows multiple variables to define the same
3388 flags without explicitly listing them for each variable.
3389
267541f7
JH
3390- CONFIG_ENV_ACCESS_IGNORE_FORCE
3391 If defined, don't allow the -f switch to env set override variable
3392 access flags.
3393
0d296cc2
GB
3394- CONFIG_USE_STDINT
3395 If stdint.h is available with your toolchain you can define this
3396 option to enable it. You can provide option 'USE_STDINT=1' when
3397 building U-Boot to enable this.
3398
c609719b
WD
3399The following definitions that deal with the placement and management
3400of environment data (variable area); in general, we support the
3401following configurations:
3402
c3eb3fe4
MF
3403- CONFIG_BUILD_ENVCRC:
3404
3405 Builds up envcrc with the target environment so that external utils
3406 may easily extract it and embed it in final U-Boot images.
3407
c609719b 3408BE CAREFUL! The first access to the environment happens quite early
b445bbb4 3409in U-Boot initialization (when we try to get the setting of for the
11ccc33f 3410console baudrate). You *MUST* have mapped your NVRAM area then, or
c609719b
WD
3411U-Boot will hang.
3412
3413Please note that even with NVRAM we still use a copy of the
3414environment in RAM: we could work on NVRAM directly, but we want to
3415keep settings there always unmodified except somebody uses "saveenv"
3416to save the current settings.
3417
0a85a9e7
LG
3418BE CAREFUL! For some special cases, the local device can not use
3419"saveenv" command. For example, the local device will get the
fc54c7fa
LG
3420environment stored in a remote NOR flash by SRIO or PCIE link,
3421but it can not erase, write this NOR flash by SRIO or PCIE interface.
0a85a9e7 3422
b74ab737
GL
3423- CONFIG_NAND_ENV_DST
3424
3425 Defines address in RAM to which the nand_spl code should copy the
3426 environment. If redundant environment is used, it will be copied to
3427 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3428
e881cb56 3429Please note that the environment is read-only until the monitor
c609719b 3430has been relocated to RAM and a RAM copy of the environment has been
cdb74977 3431created; also, when using EEPROM you will have to use getenv_f()
c609719b
WD
3432until then to read environment variables.
3433
85ec0bcc
WD
3434The environment is protected by a CRC32 checksum. Before the monitor
3435is relocated into RAM, as a result of a bad CRC you will be working
3436with the compiled-in default environment - *silently*!!! [This is
3437necessary, because the first environment variable we need is the
3438"baudrate" setting for the console - if we have a bad CRC, we don't
3439have any device yet where we could complain.]
c609719b
WD
3440
3441Note: once the monitor has been relocated, then it will complain if
3442the default environment is used; a new CRC is computed as soon as you
85ec0bcc 3443use the "saveenv" command to store a valid environment.
c609719b 3444
6d0f6bcf 3445- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
42d1f039 3446 Echo the inverted Ethernet link state to the fault LED.
fc3e2165 3447
6d0f6bcf 3448 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
fc3e2165
WD
3449 also needs to be defined.
3450
6d0f6bcf 3451- CONFIG_SYS_FAULT_MII_ADDR:
42d1f039 3452 MII address of the PHY to check for the Ethernet link state.
c609719b 3453
f5675aa5
RM
3454- CONFIG_NS16550_MIN_FUNCTIONS:
3455 Define this if you desire to only have use of the NS16550_init
3456 and NS16550_putc functions for the serial driver located at
3457 drivers/serial/ns16550.c. This option is useful for saving
3458 space for already greatly restricted images, including but not
3459 limited to NAND_SPL configurations.
3460
b2b92f53
SG
3461- CONFIG_DISPLAY_BOARDINFO
3462 Display information about the board that U-Boot is running on
3463 when U-Boot starts up. The board function checkboard() is called
3464 to do this.
3465
e2e3e2b1
SG
3466- CONFIG_DISPLAY_BOARDINFO_LATE
3467 Similar to the previous option, but display this information
3468 later, once stdio is running and output goes to the LCD, if
3469 present.
3470
feb85801
SS
3471- CONFIG_BOARD_SIZE_LIMIT:
3472 Maximum size of the U-Boot image. When defined, the
3473 build system checks that the actual size does not
3474 exceed it.
3475
c609719b 3476Low Level (hardware related) configuration options:
dc7c9a1a 3477---------------------------------------------------
c609719b 3478
6d0f6bcf 3479- CONFIG_SYS_CACHELINE_SIZE:
c609719b
WD
3480 Cache Line Size of the CPU.
3481
e46fedfe
TT
3482- CONFIG_SYS_CCSRBAR_DEFAULT:
3483 Default (power-on reset) physical address of CCSR on Freescale
3484 PowerPC SOCs.
3485
3486- CONFIG_SYS_CCSRBAR:
3487 Virtual address of CCSR. On a 32-bit build, this is typically
3488 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3489
e46fedfe
TT
3490- CONFIG_SYS_CCSRBAR_PHYS:
3491 Physical address of CCSR. CCSR can be relocated to a new
3492 physical address, if desired. In this case, this macro should
c0f40859 3493 be set to that address. Otherwise, it should be set to the
e46fedfe
TT
3494 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3495 is typically relocated on 36-bit builds. It is recommended
3496 that this macro be defined via the _HIGH and _LOW macros:
3497
3498 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3499 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3500
3501- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4cf2609b
WD
3502 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3503 either 0 (32-bit build) or 0xF (36-bit build). This macro is
e46fedfe
TT
3504 used in assembly code, so it must not contain typecasts or
3505 integer size suffixes (e.g. "ULL").
3506
3507- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3508 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3509 used in assembly code, so it must not contain typecasts or
3510 integer size suffixes (e.g. "ULL").
3511
3512- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3513 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3514 forced to a value that ensures that CCSR is not relocated.
3515
7f6c2cbc 3516- Floppy Disk Support:
6d0f6bcf 3517 CONFIG_SYS_FDC_DRIVE_NUMBER
7f6c2cbc
WD
3518
3519 the default drive number (default value 0)
3520
6d0f6bcf 3521 CONFIG_SYS_ISA_IO_STRIDE
7f6c2cbc 3522
11ccc33f 3523 defines the spacing between FDC chipset registers
7f6c2cbc
WD
3524 (default value 1)
3525
6d0f6bcf 3526 CONFIG_SYS_ISA_IO_OFFSET
7f6c2cbc 3527
43d9616c
WD
3528 defines the offset of register from address. It
3529 depends on which part of the data bus is connected to
11ccc33f 3530 the FDC chipset. (default value 0)
7f6c2cbc 3531
6d0f6bcf
JCPV
3532 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3533 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
43d9616c 3534 default value.
7f6c2cbc 3535
6d0f6bcf 3536 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
43d9616c
WD
3537 fdc_hw_init() is called at the beginning of the FDC
3538 setup. fdc_hw_init() must be provided by the board
b445bbb4 3539 source code. It is used to make hardware-dependent
43d9616c 3540 initializations.
7f6c2cbc 3541
0abddf82
ML
3542- CONFIG_IDE_AHB:
3543 Most IDE controllers were designed to be connected with PCI
3544 interface. Only few of them were designed for AHB interface.
3545 When software is doing ATA command and data transfer to
3546 IDE devices through IDE-AHB controller, some additional
3547 registers accessing to these kind of IDE-AHB controller
b445bbb4 3548 is required.
0abddf82 3549
6d0f6bcf 3550- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
efe2a4d5 3551 DO NOT CHANGE unless you know exactly what you're
907208c4 3552 doing! (11-4) [MPC8xx systems only]
c609719b 3553
6d0f6bcf 3554- CONFIG_SYS_INIT_RAM_ADDR:
c609719b 3555
7152b1d0 3556 Start address of memory area that can be used for
c609719b
WD
3557 initial data and stack; please note that this must be
3558 writable memory that is working WITHOUT special
3559 initialization, i. e. you CANNOT use normal RAM which
3560 will become available only after programming the
3561 memory controller and running certain initialization
3562 sequences.
3563
3564 U-Boot uses the following memory types:
907208c4 3565 - MPC8xx: IMMR (internal memory of the CPU)
c609719b 3566
6d0f6bcf 3567- CONFIG_SYS_GBL_DATA_OFFSET:
c609719b
WD
3568
3569 Offset of the initial data structure in the memory
6d0f6bcf
JCPV
3570 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3571 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
c609719b 3572 data is located at the end of the available space
553f0982 3573 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
acd51f9d 3574 GENERATED_GBL_DATA_SIZE), and the initial stack is just
6d0f6bcf
JCPV
3575 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3576 CONFIG_SYS_GBL_DATA_OFFSET) downward.
c609719b
WD
3577
3578 Note:
3579 On the MPC824X (or other systems that use the data
3580 cache for initial memory) the address chosen for
6d0f6bcf 3581 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
c609719b
WD
3582 point to an otherwise UNUSED address space between
3583 the top of RAM and the start of the PCI space.
3584
6d0f6bcf 3585- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
c609719b 3586
6d0f6bcf 3587- CONFIG_SYS_OR_TIMING_SDRAM:
c609719b
WD
3588 SDRAM timing
3589
6d0f6bcf 3590- CONFIG_SYS_MAMR_PTA:
c609719b
WD
3591 periodic timer for refresh
3592
6d0f6bcf
JCPV
3593- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3594 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3595 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3596 CONFIG_SYS_BR1_PRELIM:
c609719b
WD
3597 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3598
3599- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
6d0f6bcf
JCPV
3600 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3601 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
c609719b
WD
3602 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3603
69fd2d3b 3604- CONFIG_PCI_ENUM_ONLY
b445bbb4 3605 Only scan through and get the devices on the buses.
69fd2d3b
AS
3606 Don't do any setup work, presumably because someone or
3607 something has already done it, and we don't need to do it
3608 a second time. Useful for platforms that are pre-booted
3609 by coreboot or similar.
3610
842033e6
GJ
3611- CONFIG_PCI_INDIRECT_BRIDGE:
3612 Enable support for indirect PCI bridges.
3613
a09b9b68
KG
3614- CONFIG_SYS_SRIO:
3615 Chip has SRIO or not
3616
3617- CONFIG_SRIO1:
3618 Board has SRIO 1 port available
3619
3620- CONFIG_SRIO2:
3621 Board has SRIO 2 port available
3622
c8b28152
LG
3623- CONFIG_SRIO_PCIE_BOOT_MASTER
3624 Board can support master function for Boot from SRIO and PCIE
3625
a09b9b68
KG
3626- CONFIG_SYS_SRIOn_MEM_VIRT:
3627 Virtual Address of SRIO port 'n' memory region
3628
3629- CONFIG_SYS_SRIOn_MEM_PHYS:
3630 Physical Address of SRIO port 'n' memory region
3631
3632- CONFIG_SYS_SRIOn_MEM_SIZE:
3633 Size of SRIO port 'n' memory region
3634
66bd1846
FE
3635- CONFIG_SYS_NAND_BUSWIDTH_16BIT
3636 Defined to tell the NAND controller that the NAND chip is using
3637 a 16 bit bus.
3638 Not all NAND drivers use this symbol.
a430e916 3639 Example of drivers that use it:
66bd1846 3640 - drivers/mtd/nand/ndfc.c
a430e916 3641 - drivers/mtd/nand/mxc_nand.c
eced4626
AW
3642
3643- CONFIG_SYS_NDFC_EBC0_CFG
3644 Sets the EBC0_CFG register for the NDFC. If not defined
3645 a default value will be used.
3646
bb99ad6d 3647- CONFIG_SPD_EEPROM
218ca724
WD
3648 Get DDR timing information from an I2C EEPROM. Common
3649 with pluggable memory modules such as SODIMMs
3650
bb99ad6d
BW
3651 SPD_EEPROM_ADDRESS
3652 I2C address of the SPD EEPROM
3653
6d0f6bcf 3654- CONFIG_SYS_SPD_BUS_NUM
218ca724
WD
3655 If SPD EEPROM is on an I2C bus other than the first
3656 one, specify here. Note that the value must resolve
3657 to something your driver can deal with.
bb99ad6d 3658
1b3e3c4f
YS
3659- CONFIG_SYS_DDR_RAW_TIMING
3660 Get DDR timing information from other than SPD. Common with
3661 soldered DDR chips onboard without SPD. DDR raw timing
3662 parameters are extracted from datasheet and hard-coded into
3663 header files or board specific files.
3664
6f5e1dc5
YS
3665- CONFIG_FSL_DDR_INTERACTIVE
3666 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3667
e32d59a2
YS
3668- CONFIG_FSL_DDR_SYNC_REFRESH
3669 Enable sync of refresh for multiple controllers.
3670
4516ff81
YS
3671- CONFIG_FSL_DDR_BIST
3672 Enable built-in memory test for Freescale DDR controllers.
3673
6d0f6bcf 3674- CONFIG_SYS_83XX_DDR_USES_CS0
218ca724
WD
3675 Only for 83xx systems. If specified, then DDR should
3676 be configured using CS0 and CS1 instead of CS2 and CS3.
2ad6b513 3677
c26e454d
WD
3678- CONFIG_RMII
3679 Enable RMII mode for all FECs.
3680 Note that this is a global option, we can't
3681 have one FEC in standard MII mode and another in RMII mode.
3682
5cf91d6b
WD
3683- CONFIG_CRC32_VERIFY
3684 Add a verify option to the crc32 command.
3685 The syntax is:
3686
3687 => crc32 -v <address> <count> <crc32>
3688
3689 Where address/count indicate a memory area
3690 and crc32 is the correct crc32 which the
3691 area should have.
3692
56523f12
WD
3693- CONFIG_LOOPW
3694 Add the "loopw" memory command. This only takes effect if
493f420e 3695 the memory commands are activated globally (CONFIG_CMD_MEMORY).
56523f12 3696
7b466641
SR
3697- CONFIG_MX_CYCLIC
3698 Add the "mdc" and "mwc" memory commands. These are cyclic
3699 "md/mw" commands.
3700 Examples:
3701
efe2a4d5 3702 => mdc.b 10 4 500
7b466641
SR
3703 This command will print 4 bytes (10,11,12,13) each 500 ms.
3704
efe2a4d5 3705 => mwc.l 100 12345678 10
7b466641
SR
3706 This command will write 12345678 to address 100 all 10 ms.
3707
efe2a4d5 3708 This only takes effect if the memory commands are activated
493f420e 3709 globally (CONFIG_CMD_MEMORY).
7b466641 3710
8aa1a2d1 3711- CONFIG_SKIP_LOWLEVEL_INIT
afc1ce82 3712 [ARM, NDS32, MIPS only] If this variable is defined, then certain
844f07d8
WD
3713 low level initializations (like setting up the memory
3714 controller) are omitted and/or U-Boot does not
3715 relocate itself into RAM.
3716
3717 Normally this variable MUST NOT be defined. The only
3718 exception is when U-Boot is loaded (to RAM) by some
3719 other boot loader or by a debugger which performs
3720 these initializations itself.
8aa1a2d1 3721
b5bd0982
SG
3722- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3723 [ARM926EJ-S only] This allows just the call to lowlevel_init()
90211f77 3724 to be skipped. The normal CP15 init (such as enabling the
b5bd0982
SG
3725 instruction cache) is still performed.
3726
401bb30b 3727- CONFIG_SPL_BUILD
df81238b
ML
3728 Modifies the behaviour of start.S when compiling a loader
3729 that is executed before the actual U-Boot. E.g. when
3730 compiling a NAND SPL.
400558b5 3731
3aa29de0
YZ
3732- CONFIG_TPL_BUILD
3733 Modifies the behaviour of start.S when compiling a loader
3734 that is executed after the SPL and before the actual U-Boot.
3735 It is loaded by the SPL.
3736
5df572f0
YZ
3737- CONFIG_SYS_MPC85XX_NO_RESETVEC
3738 Only for 85xx systems. If this variable is specified, the section
3739 .resetvec is not kept and the section .bootpg is placed in the
3740 previous 4k of the .text section.
3741
4213fc29
SG
3742- CONFIG_ARCH_MAP_SYSMEM
3743 Generally U-Boot (and in particular the md command) uses
3744 effective address. It is therefore not necessary to regard
3745 U-Boot address as virtual addresses that need to be translated
3746 to physical addresses. However, sandbox requires this, since
3747 it maintains its own little RAM buffer which contains all
3748 addressable memory. This option causes some memory accesses
3749 to be mapped through map_sysmem() / unmap_sysmem().
3750
588a13f7
SG
3751- CONFIG_X86_RESET_VECTOR
3752 If defined, the x86 reset vector code is included. This is not
3753 needed when U-Boot is running from Coreboot.
b16f521a 3754
16678eb4
HS
3755- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
3756 Enables the RTC32K OSC on AM33xx based plattforms
3757
999d7d32
KM
3758- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3759 Option to disable subpage write in NAND driver
3760 driver that uses this:
3761 drivers/mtd/nand/davinci_nand.c
3762
f2717b47
TT
3763Freescale QE/FMAN Firmware Support:
3764-----------------------------------
3765
3766The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3767loading of "firmware", which is encoded in the QE firmware binary format.
3768This firmware often needs to be loaded during U-Boot booting, so macros
3769are used to identify the storage device (NOR flash, SPI, etc) and the address
3770within that device.
3771
dcf1d774
ZQ
3772- CONFIG_SYS_FMAN_FW_ADDR
3773 The address in the storage device where the FMAN microcode is located. The
3774 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3775 is also specified.
3776
3777- CONFIG_SYS_QE_FW_ADDR
3778 The address in the storage device where the QE microcode is located. The
f2717b47
TT
3779 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3780 is also specified.
3781
3782- CONFIG_SYS_QE_FMAN_FW_LENGTH
3783 The maximum possible size of the firmware. The firmware binary format
3784 has a field that specifies the actual size of the firmware, but it
3785 might not be possible to read any part of the firmware unless some
3786 local storage is allocated to hold the entire firmware first.
3787
3788- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3789 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3790 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3791 virtual address in NOR flash.
3792
3793- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3794 Specifies that QE/FMAN firmware is located in NAND flash.
3795 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3796
3797- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3798 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3799 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3800
292dc6c5
LG
3801- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3802 Specifies that QE/FMAN firmware is located in the remote (master)
3803 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
fc54c7fa
LG
3804 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3805 window->master inbound window->master LAW->the ucode address in
3806 master's memory space.
f2717b47 3807
b940ca64
GR
3808Freescale Layerscape Management Complex Firmware Support:
3809---------------------------------------------------------
3810The Freescale Layerscape Management Complex (MC) supports the loading of
3811"firmware".
3812This firmware often needs to be loaded during U-Boot booting, so macros
3813are used to identify the storage device (NOR flash, SPI, etc) and the address
3814within that device.
3815
3816- CONFIG_FSL_MC_ENET
3817 Enable the MC driver for Layerscape SoCs.
3818
5c055089
PK
3819Freescale Layerscape Debug Server Support:
3820-------------------------------------------
3821The Freescale Layerscape Debug Server Support supports the loading of
3822"Debug Server firmware" and triggering SP boot-rom.
3823This firmware often needs to be loaded during U-Boot booting.
3824
c0492141
YS
3825- CONFIG_SYS_MC_RSV_MEM_ALIGN
3826 Define alignment of reserved memory MC requires
5c055089 3827
f3f431a7
PK
3828Reproducible builds
3829-------------------
3830
3831In order to achieve reproducible builds, timestamps used in the U-Boot build
3832process have to be set to a fixed value.
3833
3834This is done using the SOURCE_DATE_EPOCH environment variable.
3835SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3836option for U-Boot or an environment variable in U-Boot.
3837
3838SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3839
c609719b
WD
3840Building the Software:
3841======================
3842
218ca724
WD
3843Building U-Boot has been tested in several native build environments
3844and in many different cross environments. Of course we cannot support
3845all possibly existing versions of cross development tools in all
3846(potentially obsolete) versions. In case of tool chain problems we
3847recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3848which is extensively used to build and test U-Boot.
c609719b 3849
218ca724
WD
3850If you are not using a native environment, it is assumed that you
3851have GNU cross compiling tools available in your path. In this case,
3852you must set the environment variable CROSS_COMPILE in your shell.
3853Note that no changes to the Makefile or any other source files are
3854necessary. For example using the ELDK on a 4xx CPU, please enter:
c609719b 3855
218ca724
WD
3856 $ CROSS_COMPILE=ppc_4xx-
3857 $ export CROSS_COMPILE
c609719b 3858
2f8d396b
PT
3859Note: If you wish to generate Windows versions of the utilities in
3860 the tools directory you can use the MinGW toolchain
3861 (http://www.mingw.org). Set your HOST tools to the MinGW
3862 toolchain and execute 'make tools'. For example:
3863
3864 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3865
3866 Binaries such as tools/mkimage.exe will be created which can
3867 be executed on computers running Windows.
3868
218ca724
WD
3869U-Boot is intended to be simple to build. After installing the
3870sources you must configure U-Boot for one specific board type. This
c609719b
WD
3871is done by typing:
3872
ab584d67 3873 make NAME_defconfig
c609719b 3874
ab584d67 3875where "NAME_defconfig" is the name of one of the existing configu-
4d675ae6 3876rations; see boards.cfg for supported names.
db01a2ea 3877
2729af9d
WD
3878Note: for some board special configuration names may exist; check if
3879 additional information is available from the board vendor; for
3880 instance, the TQM823L systems are available without (standard)
3881 or with LCD support. You can select such additional "features"
11ccc33f 3882 when choosing the configuration, i. e.
2729af9d 3883
ab584d67 3884 make TQM823L_defconfig
2729af9d
WD
3885 - will configure for a plain TQM823L, i. e. no LCD support
3886
ab584d67 3887 make TQM823L_LCD_defconfig
2729af9d
WD
3888 - will configure for a TQM823L with U-Boot console on LCD
3889
3890 etc.
3891
3892
3893Finally, type "make all", and you should get some working U-Boot
3894images ready for download to / installation on your system:
3895
3896- "u-boot.bin" is a raw binary image
3897- "u-boot" is an image in ELF binary format
3898- "u-boot.srec" is in Motorola S-Record format
3899
baf31249
MB
3900By default the build is performed locally and the objects are saved
3901in the source directory. One of the two methods can be used to change
3902this behavior and build U-Boot to some external directory:
3903
39041. Add O= to the make command line invocations:
3905
3906 make O=/tmp/build distclean
ab584d67 3907 make O=/tmp/build NAME_defconfig
baf31249
MB
3908 make O=/tmp/build all
3909
adbba996 39102. Set environment variable KBUILD_OUTPUT to point to the desired location:
baf31249 3911
adbba996 3912 export KBUILD_OUTPUT=/tmp/build
baf31249 3913 make distclean
ab584d67 3914 make NAME_defconfig
baf31249
MB
3915 make all
3916
adbba996 3917Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
baf31249
MB
3918variable.
3919
2729af9d
WD
3920
3921Please be aware that the Makefiles assume you are using GNU make, so
3922for instance on NetBSD you might need to use "gmake" instead of
3923native "make".
3924
3925
3926If the system board that you have is not listed, then you will need
3927to port U-Boot to your hardware platform. To do this, follow these
3928steps:
3929
3c1496cd 39301. Create a new directory to hold your board specific code. Add any
2729af9d 3931 files you need. In your board directory, you will need at least
3c1496cd
PS
3932 the "Makefile" and a "<board>.c".
39332. Create a new configuration file "include/configs/<board>.h" for
3934 your board.
2729af9d
WD
39353. If you're porting U-Boot to a new CPU, then also create a new
3936 directory to hold your CPU specific code. Add any files you need.
ab584d67 39374. Run "make <board>_defconfig" with your new name.
2729af9d
WD
39385. Type "make", and you should get a working "u-boot.srec" file
3939 to be installed on your target system.
39406. Debug and solve any problems that might arise.
3941 [Of course, this last step is much harder than it sounds.]
3942
3943
3944Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3945==============================================================
3946
218ca724
WD
3947If you have modified U-Boot sources (for instance added a new board
3948or support for new devices, a new CPU, etc.) you are expected to
2729af9d
WD
3949provide feedback to the other developers. The feedback normally takes
3950the form of a "patch", i. e. a context diff against a certain (latest
218ca724 3951official or latest in the git repository) version of U-Boot sources.
2729af9d 3952
218ca724
WD
3953But before you submit such a patch, please verify that your modifi-
3954cation did not break existing code. At least make sure that *ALL* of
2729af9d 3955the supported boards compile WITHOUT ANY compiler warnings. To do so,
6de80f21
SG
3956just run the buildman script (tools/buildman/buildman), which will
3957configure and build U-Boot for ALL supported system. Be warned, this
3958will take a while. Please see the buildman README, or run 'buildman -H'
3959for documentation.
baf31249
MB
3960
3961
2729af9d
WD
3962See also "U-Boot Porting Guide" below.
3963
3964
3965Monitor Commands - Overview:
3966============================
3967
3968go - start application at address 'addr'
3969run - run commands in an environment variable
3970bootm - boot application image from memory
3971bootp - boot image via network using BootP/TFTP protocol
44f074c7 3972bootz - boot zImage from memory
2729af9d
WD
3973tftpboot- boot image via network using TFTP protocol
3974 and env variables "ipaddr" and "serverip"
3975 (and eventually "gatewayip")
1fb7cd49 3976tftpput - upload a file via network using TFTP protocol
2729af9d
WD
3977rarpboot- boot image via network using RARP/TFTP protocol
3978diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3979loads - load S-Record file over serial line
3980loadb - load binary file over serial line (kermit mode)
3981md - memory display
3982mm - memory modify (auto-incrementing)
3983nm - memory modify (constant address)
3984mw - memory write (fill)
3985cp - memory copy
3986cmp - memory compare
3987crc32 - checksum calculation
0f89c54b 3988i2c - I2C sub-system
2729af9d
WD
3989sspi - SPI utility commands
3990base - print or set address offset
3991printenv- print environment variables
3992setenv - set environment variables
3993saveenv - save environment variables to persistent storage
3994protect - enable or disable FLASH write protection
3995erase - erase FLASH memory
3996flinfo - print FLASH memory information
10635afa 3997nand - NAND memory operations (see doc/README.nand)
2729af9d
WD
3998bdinfo - print Board Info structure
3999iminfo - print header information for application image
4000coninfo - print console devices and informations
4001ide - IDE sub-system
4002loop - infinite loop on address range
56523f12 4003loopw - infinite write loop on address range
2729af9d
WD
4004mtest - simple RAM test
4005icache - enable or disable instruction cache
4006dcache - enable or disable data cache
4007reset - Perform RESET of the CPU
4008echo - echo args to console
4009version - print monitor version
4010help - print online help
4011? - alias for 'help'
4012
4013
4014Monitor Commands - Detailed Description:
4015========================================
4016
4017TODO.
4018
4019For now: just type "help <command>".
4020
4021
4022Environment Variables:
4023======================
4024
4025U-Boot supports user configuration using Environment Variables which
4026can be made persistent by saving to Flash memory.
c609719b 4027
2729af9d
WD
4028Environment Variables are set using "setenv", printed using
4029"printenv", and saved to Flash using "saveenv". Using "setenv"
4030without a value can be used to delete a variable from the
4031environment. As long as you don't save the environment you are
4032working with an in-memory copy. In case the Flash area containing the
4033environment is erased by accident, a default environment is provided.
c609719b 4034
c96f86ee
WD
4035Some configuration options can be set using Environment Variables.
4036
4037List of environment variables (most likely not complete):
c609719b 4038
2729af9d 4039 baudrate - see CONFIG_BAUDRATE
c609719b 4040
2729af9d 4041 bootdelay - see CONFIG_BOOTDELAY
c609719b 4042
2729af9d 4043 bootcmd - see CONFIG_BOOTCOMMAND
4a6fd34b 4044
2729af9d 4045 bootargs - Boot arguments when booting an RTOS image
c609719b 4046
2729af9d 4047 bootfile - Name of the image to load with TFTP
c609719b 4048
7d721e34
BS
4049 bootm_low - Memory range available for image processing in the bootm
4050 command can be restricted. This variable is given as
4051 a hexadecimal number and defines lowest address allowed
4052 for use by the bootm command. See also "bootm_size"
4053 environment variable. Address defined by "bootm_low" is
4054 also the base of the initial memory mapping for the Linux
c3624e6e
GL
4055 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4056 bootm_mapsize.
4057
c0f40859 4058 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
c3624e6e
GL
4059 This variable is given as a hexadecimal number and it
4060 defines the size of the memory region starting at base
4061 address bootm_low that is accessible by the Linux kernel
4062 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4063 as the default value if it is defined, and bootm_size is
4064 used otherwise.
7d721e34
BS
4065
4066 bootm_size - Memory range available for image processing in the bootm
4067 command can be restricted. This variable is given as
4068 a hexadecimal number and defines the size of the region
4069 allowed for use by the bootm command. See also "bootm_low"
4070 environment variable.
4071
4bae9090
BS
4072 updatefile - Location of the software update file on a TFTP server, used
4073 by the automatic software update feature. Please refer to
4074 documentation in doc/README.update for more details.
4075
2729af9d
WD
4076 autoload - if set to "no" (any string beginning with 'n'),
4077 "bootp" will just load perform a lookup of the
4078 configuration from the BOOTP server, but not try to
4079 load any image using TFTP
c609719b 4080
2729af9d
WD
4081 autostart - if set to "yes", an image loaded using the "bootp",
4082 "rarpboot", "tftpboot" or "diskboot" commands will
4083 be automatically started (by internally calling
4084 "bootm")
38b99261 4085
2729af9d
WD
4086 If set to "no", a standalone image passed to the
4087 "bootm" command will be copied to the load address
4088 (and eventually uncompressed), but NOT be started.
4089 This can be used to load and uncompress arbitrary
4090 data.
c609719b 4091
a28afca5
DL
4092 fdt_high - if set this restricts the maximum address that the
4093 flattened device tree will be copied into upon boot.
fa34f6b2
SG
4094 For example, if you have a system with 1 GB memory
4095 at physical address 0x10000000, while Linux kernel
4096 only recognizes the first 704 MB as low memory, you
4097 may need to set fdt_high as 0x3C000000 to have the
4098 device tree blob be copied to the maximum address
4099 of the 704 MB low memory, so that Linux kernel can
4100 access it during the boot procedure.
4101
a28afca5
DL
4102 If this is set to the special value 0xFFFFFFFF then
4103 the fdt will not be copied at all on boot. For this
4104 to work it must reside in writable memory, have
4105 sufficient padding on the end of it for u-boot to
4106 add the information it needs into it, and the memory
4107 must be accessible by the kernel.
4108
eea63e05
SG
4109 fdtcontroladdr- if set this is the address of the control flattened
4110 device tree used by U-Boot when CONFIG_OF_CONTROL is
4111 defined.
4112
17ea1177
WD
4113 i2cfast - (PPC405GP|PPC405EP only)
4114 if set to 'y' configures Linux I2C driver for fast
4115 mode (400kHZ). This environment variable is used in
4116 initialization code. So, for changes to be effective
4117 it must be saved and board must be reset.
4118
2729af9d
WD
4119 initrd_high - restrict positioning of initrd images:
4120 If this variable is not set, initrd images will be
4121 copied to the highest possible address in RAM; this
4122 is usually what you want since it allows for
4123 maximum initrd size. If for some reason you want to
4124 make sure that the initrd image is loaded below the
6d0f6bcf 4125 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
2729af9d
WD
4126 variable to a value of "no" or "off" or "0".
4127 Alternatively, you can set it to a maximum upper
4128 address to use (U-Boot will still check that it
4129 does not overwrite the U-Boot stack and data).
c609719b 4130
2729af9d
WD
4131 For instance, when you have a system with 16 MB
4132 RAM, and want to reserve 4 MB from use by Linux,
4133 you can do this by adding "mem=12M" to the value of
4134 the "bootargs" variable. However, now you must make
4135 sure that the initrd image is placed in the first
4136 12 MB as well - this can be done with
c609719b 4137
2729af9d 4138 setenv initrd_high 00c00000
c609719b 4139
2729af9d
WD
4140 If you set initrd_high to 0xFFFFFFFF, this is an
4141 indication to U-Boot that all addresses are legal
4142 for the Linux kernel, including addresses in flash
4143 memory. In this case U-Boot will NOT COPY the
4144 ramdisk at all. This may be useful to reduce the
4145 boot time on your system, but requires that this
4146 feature is supported by your Linux kernel.
c609719b 4147
2729af9d 4148 ipaddr - IP address; needed for tftpboot command
c609719b 4149
2729af9d
WD
4150 loadaddr - Default load address for commands like "bootp",
4151 "rarpboot", "tftpboot", "loadb" or "diskboot"
c609719b 4152
2729af9d 4153 loads_echo - see CONFIG_LOADS_ECHO
a3d991bd 4154
2729af9d 4155 serverip - TFTP server IP address; needed for tftpboot command
a3d991bd 4156
2729af9d 4157 bootretry - see CONFIG_BOOT_RETRY_TIME
a3d991bd 4158
2729af9d 4159 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
a3d991bd 4160
2729af9d 4161 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
c609719b 4162
e2a53458 4163 ethprime - controls which interface is used first.
c609719b 4164
e2a53458
MF
4165 ethact - controls which interface is currently active.
4166 For example you can do the following
c609719b 4167
48690d80
HS
4168 => setenv ethact FEC
4169 => ping 192.168.0.1 # traffic sent on FEC
4170 => setenv ethact SCC
4171 => ping 10.0.0.1 # traffic sent on SCC
c609719b 4172
e1692577
MF
4173 ethrotate - When set to "no" U-Boot does not go through all
4174 available network interfaces.
4175 It just stays at the currently selected interface.
4176
c96f86ee 4177 netretry - When set to "no" each network operation will
2729af9d
WD
4178 either succeed or fail without retrying.
4179 When set to "once" the network operation will
4180 fail when all the available network interfaces
4181 are tried once without success.
4182 Useful on scripts which control the retry operation
4183 themselves.
c609719b 4184
b4e2f89d 4185 npe_ucode - set load address for the NPE microcode
a1cf027a 4186
b445bbb4 4187 silent_linux - If set then Linux will be told to boot silently, by
8d51aacd
SG
4188 changing the console to be empty. If "yes" it will be
4189 made silent. If "no" it will not be made silent. If
4190 unset, then it will be made silent if the U-Boot console
4191 is silent.
4192
f5fb7346 4193 tftpsrcp - If this is set, the value is used for TFTP's
ecb0ccd9
WD
4194 UDP source port.
4195
f5fb7346 4196 tftpdstp - If this is set, the value is used for TFTP's UDP
28cb9375
WD
4197 destination port instead of the Well Know Port 69.
4198
c96f86ee
WD
4199 tftpblocksize - Block size to use for TFTP transfers; if not set,
4200 we use the TFTP server's default block size
4201
4202 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4203 seconds, minimum value is 1000 = 1 second). Defines
4204 when a packet is considered to be lost so it has to
4205 be retransmitted. The default is 5000 = 5 seconds.
4206 Lowering this value may make downloads succeed
4207 faster in networks with high packet loss rates or
4208 with unreliable TFTP servers.
4209
f5fb7346
AA
4210 tftptimeoutcountmax - maximum count of TFTP timeouts (no
4211 unit, minimum value = 0). Defines how many timeouts
4212 can happen during a single file transfer before that
4213 transfer is aborted. The default is 10, and 0 means
4214 'no timeouts allowed'. Increasing this value may help
4215 downloads succeed with high packet loss rates, or with
4216 unreliable TFTP servers or client hardware.
4217
c96f86ee 4218 vlan - When set to a value < 4095 the traffic over
11ccc33f 4219 Ethernet is encapsulated/received over 802.1q
2729af9d 4220 VLAN tagged frames.
c609719b 4221
50768f5b
AM
4222 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
4223 Unsigned value, in milliseconds. If not set, the period will
4224 be either the default (28000), or a value based on
4225 CONFIG_NET_RETRY_COUNT, if defined. This value has
4226 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
4227
dc0b7b0e
JH
4228The following image location variables contain the location of images
4229used in booting. The "Image" column gives the role of the image and is
4230not an environment variable name. The other columns are environment
4231variable names. "File Name" gives the name of the file on a TFTP
4232server, "RAM Address" gives the location in RAM the image will be
4233loaded to, and "Flash Location" gives the image's address in NOR
4234flash or offset in NAND flash.
4235
4236*Note* - these variables don't have to be defined for all boards, some
aed9fed9 4237boards currently use other variables for these purposes, and some
dc0b7b0e
JH
4238boards use these variables for other purposes.
4239
c0f40859
WD
4240Image File Name RAM Address Flash Location
4241----- --------- ----------- --------------
4242u-boot u-boot u-boot_addr_r u-boot_addr
4243Linux kernel bootfile kernel_addr_r kernel_addr
4244device tree blob fdtfile fdt_addr_r fdt_addr
4245ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
dc0b7b0e 4246
2729af9d
WD
4247The following environment variables may be used and automatically
4248updated by the network boot commands ("bootp" and "rarpboot"),
4249depending the information provided by your boot server:
c609719b 4250
2729af9d
WD
4251 bootfile - see above
4252 dnsip - IP address of your Domain Name Server
4253 dnsip2 - IP address of your secondary Domain Name Server
4254 gatewayip - IP address of the Gateway (Router) to use
4255 hostname - Target hostname
4256 ipaddr - see above
4257 netmask - Subnet Mask
4258 rootpath - Pathname of the root filesystem on the NFS server
4259 serverip - see above
c1551ea8 4260
c1551ea8 4261
2729af9d 4262There are two special Environment Variables:
c1551ea8 4263
2729af9d
WD
4264 serial# - contains hardware identification information such
4265 as type string and/or serial number
4266 ethaddr - Ethernet address
c609719b 4267
2729af9d
WD
4268These variables can be set only once (usually during manufacturing of
4269the board). U-Boot refuses to delete or overwrite these variables
4270once they have been set once.
c609719b 4271
f07771cc 4272
2729af9d 4273Further special Environment Variables:
f07771cc 4274
2729af9d
WD
4275 ver - Contains the U-Boot version string as printed
4276 with the "version" command. This variable is
4277 readonly (see CONFIG_VERSION_VARIABLE).
f07771cc 4278
f07771cc 4279
2729af9d
WD
4280Please note that changes to some configuration parameters may take
4281only effect after the next boot (yes, that's just like Windoze :-).
f07771cc 4282
f07771cc 4283
170ab110
JH
4284Callback functions for environment variables:
4285---------------------------------------------
4286
4287For some environment variables, the behavior of u-boot needs to change
b445bbb4 4288when their values are changed. This functionality allows functions to
170ab110
JH
4289be associated with arbitrary variables. On creation, overwrite, or
4290deletion, the callback will provide the opportunity for some side
4291effect to happen or for the change to be rejected.
4292
4293The callbacks are named and associated with a function using the
4294U_BOOT_ENV_CALLBACK macro in your board or driver code.
4295
4296These callbacks are associated with variables in one of two ways. The
4297static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4298in the board configuration to a string that defines a list of
4299associations. The list must be in the following format:
4300
4301 entry = variable_name[:callback_name]
4302 list = entry[,list]
4303
4304If the callback name is not specified, then the callback is deleted.
4305Spaces are also allowed anywhere in the list.
4306
4307Callbacks can also be associated by defining the ".callbacks" variable
4308with the same list format above. Any association in ".callbacks" will
4309override any association in the static list. You can define
4310CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
b445bbb4 4311".callbacks" environment variable in the default or embedded environment.
170ab110 4312
bdf1fe4e
JH
4313If CONFIG_REGEX is defined, the variable_name above is evaluated as a
4314regular expression. This allows multiple variables to be connected to
4315the same callback without explicitly listing them all out.
4316
170ab110 4317
2729af9d
WD
4318Command Line Parsing:
4319=====================
f07771cc 4320
2729af9d
WD
4321There are two different command line parsers available with U-Boot:
4322the old "simple" one, and the much more powerful "hush" shell:
c609719b 4323
2729af9d
WD
4324Old, simple command line parser:
4325--------------------------------
c609719b 4326
2729af9d
WD
4327- supports environment variables (through setenv / saveenv commands)
4328- several commands on one line, separated by ';'
fe126d8b 4329- variable substitution using "... ${name} ..." syntax
2729af9d
WD
4330- special characters ('$', ';') can be escaped by prefixing with '\',
4331 for example:
fe126d8b 4332 setenv bootcmd bootm \${address}
2729af9d
WD
4333- You can also escape text by enclosing in single apostrophes, for example:
4334 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
c609719b 4335
2729af9d
WD
4336Hush shell:
4337-----------
c609719b 4338
2729af9d
WD
4339- similar to Bourne shell, with control structures like
4340 if...then...else...fi, for...do...done; while...do...done,
4341 until...do...done, ...
4342- supports environment ("global") variables (through setenv / saveenv
4343 commands) and local shell variables (through standard shell syntax
4344 "name=value"); only environment variables can be used with "run"
4345 command
4346
4347General rules:
4348--------------
c609719b 4349
2729af9d
WD
4350(1) If a command line (or an environment variable executed by a "run"
4351 command) contains several commands separated by semicolon, and
4352 one of these commands fails, then the remaining commands will be
4353 executed anyway.
c609719b 4354
2729af9d 4355(2) If you execute several variables with one call to run (i. e.
11ccc33f 4356 calling run with a list of variables as arguments), any failing
2729af9d
WD
4357 command will cause "run" to terminate, i. e. the remaining
4358 variables are not executed.
c609719b 4359
2729af9d
WD
4360Note for Redundant Ethernet Interfaces:
4361=======================================
c609719b 4362
11ccc33f 4363Some boards come with redundant Ethernet interfaces; U-Boot supports
2729af9d
WD
4364such configurations and is capable of automatic selection of a
4365"working" interface when needed. MAC assignment works as follows:
c609719b 4366
2729af9d
WD
4367Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4368MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4369"eth1addr" (=>eth1), "eth2addr", ...
c609719b 4370
2729af9d
WD
4371If the network interface stores some valid MAC address (for instance
4372in SROM), this is used as default address if there is NO correspon-
4373ding setting in the environment; if the corresponding environment
4374variable is set, this overrides the settings in the card; that means:
c609719b 4375
2729af9d
WD
4376o If the SROM has a valid MAC address, and there is no address in the
4377 environment, the SROM's address is used.
c609719b 4378
2729af9d
WD
4379o If there is no valid address in the SROM, and a definition in the
4380 environment exists, then the value from the environment variable is
4381 used.
c609719b 4382
2729af9d
WD
4383o If both the SROM and the environment contain a MAC address, and
4384 both addresses are the same, this MAC address is used.
c609719b 4385
2729af9d
WD
4386o If both the SROM and the environment contain a MAC address, and the
4387 addresses differ, the value from the environment is used and a
4388 warning is printed.
c609719b 4389
2729af9d 4390o If neither SROM nor the environment contain a MAC address, an error
bef1014b
JH
4391 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
4392 a random, locally-assigned MAC is used.
c609719b 4393
ecee9324 4394If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
c0f40859 4395will be programmed into hardware as part of the initialization process. This
ecee9324
BW
4396may be skipped by setting the appropriate 'ethmacskip' environment variable.
4397The naming convention is as follows:
4398"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
c609719b 4399
2729af9d
WD
4400Image Formats:
4401==============
c609719b 4402
3310c549
MB
4403U-Boot is capable of booting (and performing other auxiliary operations on)
4404images in two formats:
4405
4406New uImage format (FIT)
4407-----------------------
4408
4409Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4410to Flattened Device Tree). It allows the use of images with multiple
4411components (several kernels, ramdisks, etc.), with contents protected by
4412SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4413
4414
4415Old uImage format
4416-----------------
4417
4418Old image format is based on binary files which can be basically anything,
4419preceded by a special header; see the definitions in include/image.h for
4420details; basically, the header defines the following image properties:
c609719b 4421
2729af9d
WD
4422* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4423 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
f5ed9e39
PT
4424 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4425 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4426 INTEGRITY).
daab59ac 4427* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
afc1ce82 4428 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
daab59ac 4429 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
2729af9d
WD
4430* Compression Type (uncompressed, gzip, bzip2)
4431* Load Address
4432* Entry Point
4433* Image Name
4434* Image Timestamp
c609719b 4435
2729af9d
WD
4436The header is marked by a special Magic Number, and both the header
4437and the data portions of the image are secured against corruption by
4438CRC32 checksums.
c609719b
WD
4439
4440
2729af9d
WD
4441Linux Support:
4442==============
c609719b 4443
2729af9d
WD
4444Although U-Boot should support any OS or standalone application
4445easily, the main focus has always been on Linux during the design of
4446U-Boot.
c609719b 4447
2729af9d
WD
4448U-Boot includes many features that so far have been part of some
4449special "boot loader" code within the Linux kernel. Also, any
4450"initrd" images to be used are no longer part of one big Linux image;
4451instead, kernel and "initrd" are separate images. This implementation
4452serves several purposes:
c609719b 4453
2729af9d
WD
4454- the same features can be used for other OS or standalone
4455 applications (for instance: using compressed images to reduce the
4456 Flash memory footprint)
c609719b 4457
2729af9d
WD
4458- it becomes much easier to port new Linux kernel versions because
4459 lots of low-level, hardware dependent stuff are done by U-Boot
c609719b 4460
2729af9d
WD
4461- the same Linux kernel image can now be used with different "initrd"
4462 images; of course this also means that different kernel images can
4463 be run with the same "initrd". This makes testing easier (you don't
4464 have to build a new "zImage.initrd" Linux image when you just
4465 change a file in your "initrd"). Also, a field-upgrade of the
4466 software is easier now.
c609719b 4467
c609719b 4468
2729af9d
WD
4469Linux HOWTO:
4470============
c609719b 4471
2729af9d
WD
4472Porting Linux to U-Boot based systems:
4473---------------------------------------
c609719b 4474
2729af9d
WD
4475U-Boot cannot save you from doing all the necessary modifications to
4476configure the Linux device drivers for use with your target hardware
4477(no, we don't intend to provide a full virtual machine interface to
4478Linux :-).
c609719b 4479
a47a12be 4480But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
24ee89b9 4481
2729af9d
WD
4482Just make sure your machine specific header file (for instance
4483include/asm-ppc/tqm8xx.h) includes the same definition of the Board
1dc30693
MH
4484Information structure as we define in include/asm-<arch>/u-boot.h,
4485and make sure that your definition of IMAP_ADDR uses the same value
6d0f6bcf 4486as your U-Boot configuration in CONFIG_SYS_IMMR.
24ee89b9 4487
2eb31b13
SG
4488Note that U-Boot now has a driver model, a unified model for drivers.
4489If you are adding a new driver, plumb it into driver model. If there
4490is no uclass available, you are encouraged to create one. See
4491doc/driver-model.
4492
c609719b 4493
2729af9d
WD
4494Configuring the Linux kernel:
4495-----------------------------
c609719b 4496
2729af9d
WD
4497No specific requirements for U-Boot. Make sure you have some root
4498device (initial ramdisk, NFS) for your target system.
4499
4500
4501Building a Linux Image:
4502-----------------------
c609719b 4503
2729af9d
WD
4504With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4505not used. If you use recent kernel source, a new build target
4506"uImage" will exist which automatically builds an image usable by
4507U-Boot. Most older kernels also have support for a "pImage" target,
4508which was introduced for our predecessor project PPCBoot and uses a
4509100% compatible format.
4510
4511Example:
4512
ab584d67 4513 make TQM850L_defconfig
2729af9d
WD
4514 make oldconfig
4515 make dep
4516 make uImage
4517
4518The "uImage" build target uses a special tool (in 'tools/mkimage') to
4519encapsulate a compressed Linux kernel image with header information,
4520CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4521
4522* build a standard "vmlinux" kernel image (in ELF binary format):
4523
4524* convert the kernel into a raw binary image:
4525
4526 ${CROSS_COMPILE}-objcopy -O binary \
4527 -R .note -R .comment \
4528 -S vmlinux linux.bin
4529
4530* compress the binary image:
4531
4532 gzip -9 linux.bin
4533
4534* package compressed binary image for U-Boot:
4535
4536 mkimage -A ppc -O linux -T kernel -C gzip \
4537 -a 0 -e 0 -n "Linux Kernel Image" \
4538 -d linux.bin.gz uImage
c609719b 4539
c609719b 4540
2729af9d
WD
4541The "mkimage" tool can also be used to create ramdisk images for use
4542with U-Boot, either separated from the Linux kernel image, or
4543combined into one file. "mkimage" encapsulates the images with a 64
4544byte header containing information about target architecture,
4545operating system, image type, compression method, entry points, time
4546stamp, CRC32 checksums, etc.
4547
4548"mkimage" can be called in two ways: to verify existing images and
4549print the header information, or to build new images.
4550
4551In the first form (with "-l" option) mkimage lists the information
4552contained in the header of an existing U-Boot image; this includes
4553checksum verification:
c609719b 4554
2729af9d
WD
4555 tools/mkimage -l image
4556 -l ==> list image header information
4557
4558The second form (with "-d" option) is used to build a U-Boot image
4559from a "data file" which is used as image payload:
4560
4561 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4562 -n name -d data_file image
4563 -A ==> set architecture to 'arch'
4564 -O ==> set operating system to 'os'
4565 -T ==> set image type to 'type'
4566 -C ==> set compression type 'comp'
4567 -a ==> set load address to 'addr' (hex)
4568 -e ==> set entry point to 'ep' (hex)
4569 -n ==> set image name to 'name'
4570 -d ==> use image data from 'datafile'
4571
69459791
WD
4572Right now, all Linux kernels for PowerPC systems use the same load
4573address (0x00000000), but the entry point address depends on the
4574kernel version:
2729af9d
WD
4575
4576- 2.2.x kernels have the entry point at 0x0000000C,
4577- 2.3.x and later kernels have the entry point at 0x00000000.
4578
4579So a typical call to build a U-Boot image would read:
4580
4581 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4582 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
a47a12be 4583 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
2729af9d
WD
4584 > examples/uImage.TQM850L
4585 Image Name: 2.4.4 kernel for TQM850L
4586 Created: Wed Jul 19 02:34:59 2000
4587 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4588 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4589 Load Address: 0x00000000
4590 Entry Point: 0x00000000
4591
4592To verify the contents of the image (or check for corruption):
4593
4594 -> tools/mkimage -l examples/uImage.TQM850L
4595 Image Name: 2.4.4 kernel for TQM850L
4596 Created: Wed Jul 19 02:34:59 2000
4597 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4598 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4599 Load Address: 0x00000000
4600 Entry Point: 0x00000000
4601
4602NOTE: for embedded systems where boot time is critical you can trade
4603speed for memory and install an UNCOMPRESSED image instead: this
4604needs more space in Flash, but boots much faster since it does not
4605need to be uncompressed:
4606
a47a12be 4607 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
2729af9d
WD
4608 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4609 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
a47a12be 4610 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
2729af9d
WD
4611 > examples/uImage.TQM850L-uncompressed
4612 Image Name: 2.4.4 kernel for TQM850L
4613 Created: Wed Jul 19 02:34:59 2000
4614 Image Type: PowerPC Linux Kernel Image (uncompressed)
4615 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4616 Load Address: 0x00000000
4617 Entry Point: 0x00000000
4618
4619
4620Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4621when your kernel is intended to use an initial ramdisk:
4622
4623 -> tools/mkimage -n 'Simple Ramdisk Image' \
4624 > -A ppc -O linux -T ramdisk -C gzip \
4625 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4626 Image Name: Simple Ramdisk Image
4627 Created: Wed Jan 12 14:01:50 2000
4628 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4629 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4630 Load Address: 0x00000000
4631 Entry Point: 0x00000000
4632
a804b5ce
GMF
4633The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
4634option performs the converse operation of the mkimage's second form (the "-d"
4635option). Given an image built by mkimage, the dumpimage extracts a "data file"
4636from the image:
4637
f41f5b7c
GMF
4638 tools/dumpimage -i image -T type -p position data_file
4639 -i ==> extract from the 'image' a specific 'data_file'
4640 -T ==> set image type to 'type'
4641 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
a804b5ce 4642
2729af9d
WD
4643
4644Installing a Linux Image:
4645-------------------------
4646
4647To downloading a U-Boot image over the serial (console) interface,
4648you must convert the image to S-Record format:
4649
4650 objcopy -I binary -O srec examples/image examples/image.srec
4651
4652The 'objcopy' does not understand the information in the U-Boot
4653image header, so the resulting S-Record file will be relative to
4654address 0x00000000. To load it to a given address, you need to
4655specify the target address as 'offset' parameter with the 'loads'
4656command.
4657
4658Example: install the image to address 0x40100000 (which on the
4659TQM8xxL is in the first Flash bank):
4660
4661 => erase 40100000 401FFFFF
4662
4663 .......... done
4664 Erased 8 sectors
4665
4666 => loads 40100000
4667 ## Ready for S-Record download ...
4668 ~>examples/image.srec
4669 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4670 ...
4671 15989 15990 15991 15992
4672 [file transfer complete]
4673 [connected]
4674 ## Start Addr = 0x00000000
4675
4676
4677You can check the success of the download using the 'iminfo' command;
218ca724 4678this includes a checksum verification so you can be sure no data
2729af9d
WD
4679corruption happened:
4680
4681 => imi 40100000
4682
4683 ## Checking Image at 40100000 ...
4684 Image Name: 2.2.13 for initrd on TQM850L
4685 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4686 Data Size: 335725 Bytes = 327 kB = 0 MB
4687 Load Address: 00000000
4688 Entry Point: 0000000c
4689 Verifying Checksum ... OK
4690
4691
4692Boot Linux:
4693-----------
4694
4695The "bootm" command is used to boot an application that is stored in
4696memory (RAM or Flash). In case of a Linux kernel image, the contents
4697of the "bootargs" environment variable is passed to the kernel as
4698parameters. You can check and modify this variable using the
4699"printenv" and "setenv" commands:
4700
4701
4702 => printenv bootargs
4703 bootargs=root=/dev/ram
4704
4705 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4706
4707 => printenv bootargs
4708 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4709
4710 => bootm 40020000
4711 ## Booting Linux kernel at 40020000 ...
4712 Image Name: 2.2.13 for NFS on TQM850L
4713 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4714 Data Size: 381681 Bytes = 372 kB = 0 MB
4715 Load Address: 00000000
4716 Entry Point: 0000000c
4717 Verifying Checksum ... OK
4718 Uncompressing Kernel Image ... OK
4719 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
4720 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4721 time_init: decrementer frequency = 187500000/60
4722 Calibrating delay loop... 49.77 BogoMIPS
4723 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4724 ...
4725
11ccc33f 4726If you want to boot a Linux kernel with initial RAM disk, you pass
2729af9d
WD
4727the memory addresses of both the kernel and the initrd image (PPBCOOT
4728format!) to the "bootm" command:
4729
4730 => imi 40100000 40200000
4731
4732 ## Checking Image at 40100000 ...
4733 Image Name: 2.2.13 for initrd on TQM850L
4734 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4735 Data Size: 335725 Bytes = 327 kB = 0 MB
4736 Load Address: 00000000
4737 Entry Point: 0000000c
4738 Verifying Checksum ... OK
4739
4740 ## Checking Image at 40200000 ...
4741 Image Name: Simple Ramdisk Image
4742 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4743 Data Size: 566530 Bytes = 553 kB = 0 MB
4744 Load Address: 00000000
4745 Entry Point: 00000000
4746 Verifying Checksum ... OK
4747
4748 => bootm 40100000 40200000
4749 ## Booting Linux kernel at 40100000 ...
4750 Image Name: 2.2.13 for initrd on TQM850L
4751 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4752 Data Size: 335725 Bytes = 327 kB = 0 MB
4753 Load Address: 00000000
4754 Entry Point: 0000000c
4755 Verifying Checksum ... OK
4756 Uncompressing Kernel Image ... OK
4757 ## Loading RAMDisk Image at 40200000 ...
4758 Image Name: Simple Ramdisk Image
4759 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4760 Data Size: 566530 Bytes = 553 kB = 0 MB
4761 Load Address: 00000000
4762 Entry Point: 00000000
4763 Verifying Checksum ... OK
4764 Loading Ramdisk ... OK
4765 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
4766 Boot arguments: root=/dev/ram
4767 time_init: decrementer frequency = 187500000/60
4768 Calibrating delay loop... 49.77 BogoMIPS
4769 ...
4770 RAMDISK: Compressed image found at block 0
4771 VFS: Mounted root (ext2 filesystem).
4772
4773 bash#
4774
0267768e
MM
4775Boot Linux and pass a flat device tree:
4776-----------
4777
4778First, U-Boot must be compiled with the appropriate defines. See the section
4779titled "Linux Kernel Interface" above for a more in depth explanation. The
4780following is an example of how to start a kernel and pass an updated
4781flat device tree:
4782
4783=> print oftaddr
4784oftaddr=0x300000
4785=> print oft
4786oft=oftrees/mpc8540ads.dtb
4787=> tftp $oftaddr $oft
4788Speed: 1000, full duplex
4789Using TSEC0 device
4790TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4791Filename 'oftrees/mpc8540ads.dtb'.
4792Load address: 0x300000
4793Loading: #
4794done
4795Bytes transferred = 4106 (100a hex)
4796=> tftp $loadaddr $bootfile
4797Speed: 1000, full duplex
4798Using TSEC0 device
4799TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4800Filename 'uImage'.
4801Load address: 0x200000
4802Loading:############
4803done
4804Bytes transferred = 1029407 (fb51f hex)
4805=> print loadaddr
4806loadaddr=200000
4807=> print oftaddr
4808oftaddr=0x300000
4809=> bootm $loadaddr - $oftaddr
4810## Booting image at 00200000 ...
a9398e01
WD
4811 Image Name: Linux-2.6.17-dirty
4812 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4813 Data Size: 1029343 Bytes = 1005.2 kB
0267768e 4814 Load Address: 00000000
a9398e01 4815 Entry Point: 00000000
0267768e
MM
4816 Verifying Checksum ... OK
4817 Uncompressing Kernel Image ... OK
4818Booting using flat device tree at 0x300000
4819Using MPC85xx ADS machine description
4820Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4821[snip]
4822
4823
2729af9d
WD
4824More About U-Boot Image Types:
4825------------------------------
4826
4827U-Boot supports the following image types:
4828
4829 "Standalone Programs" are directly runnable in the environment
4830 provided by U-Boot; it is expected that (if they behave
4831 well) you can continue to work in U-Boot after return from
4832 the Standalone Program.
4833 "OS Kernel Images" are usually images of some Embedded OS which
4834 will take over control completely. Usually these programs
4835 will install their own set of exception handlers, device
4836 drivers, set up the MMU, etc. - this means, that you cannot
4837 expect to re-enter U-Boot except by resetting the CPU.
4838 "RAMDisk Images" are more or less just data blocks, and their
4839 parameters (address, size) are passed to an OS kernel that is
4840 being started.
4841 "Multi-File Images" contain several images, typically an OS
4842 (Linux) kernel image and one or more data images like
4843 RAMDisks. This construct is useful for instance when you want
4844 to boot over the network using BOOTP etc., where the boot
4845 server provides just a single image file, but you want to get
4846 for instance an OS kernel and a RAMDisk image.
4847
4848 "Multi-File Images" start with a list of image sizes, each
4849 image size (in bytes) specified by an "uint32_t" in network
4850 byte order. This list is terminated by an "(uint32_t)0".
4851 Immediately after the terminating 0 follow the images, one by
4852 one, all aligned on "uint32_t" boundaries (size rounded up to
4853 a multiple of 4 bytes).
4854
4855 "Firmware Images" are binary images containing firmware (like
4856 U-Boot or FPGA images) which usually will be programmed to
4857 flash memory.
4858
4859 "Script files" are command sequences that will be executed by
4860 U-Boot's command interpreter; this feature is especially
4861 useful when you configure U-Boot to use a real shell (hush)
4862 as command interpreter.
4863
44f074c7
MV
4864Booting the Linux zImage:
4865-------------------------
4866
4867On some platforms, it's possible to boot Linux zImage. This is done
4868using the "bootz" command. The syntax of "bootz" command is the same
4869as the syntax of "bootm" command.
4870
8ac28563 4871Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
017e1f3f
MV
4872kernel with raw initrd images. The syntax is slightly different, the
4873address of the initrd must be augmented by it's size, in the following
4874format: "<initrd addres>:<initrd size>".
4875
2729af9d
WD
4876
4877Standalone HOWTO:
4878=================
4879
4880One of the features of U-Boot is that you can dynamically load and
4881run "standalone" applications, which can use some resources of
4882U-Boot like console I/O functions or interrupt services.
4883
4884Two simple examples are included with the sources:
4885
4886"Hello World" Demo:
4887-------------------
4888
4889'examples/hello_world.c' contains a small "Hello World" Demo
4890application; it is automatically compiled when you build U-Boot.
4891It's configured to run at address 0x00040004, so you can play with it
4892like that:
4893
4894 => loads
4895 ## Ready for S-Record download ...
4896 ~>examples/hello_world.srec
4897 1 2 3 4 5 6 7 8 9 10 11 ...
4898 [file transfer complete]
4899 [connected]
4900 ## Start Addr = 0x00040004
4901
4902 => go 40004 Hello World! This is a test.
4903 ## Starting application at 0x00040004 ...
4904 Hello World
4905 argc = 7
4906 argv[0] = "40004"
4907 argv[1] = "Hello"
4908 argv[2] = "World!"
4909 argv[3] = "This"
4910 argv[4] = "is"
4911 argv[5] = "a"
4912 argv[6] = "test."
4913 argv[7] = "<NULL>"
4914 Hit any key to exit ...
4915
4916 ## Application terminated, rc = 0x0
4917
4918Another example, which demonstrates how to register a CPM interrupt
4919handler with the U-Boot code, can be found in 'examples/timer.c'.
4920Here, a CPM timer is set up to generate an interrupt every second.
4921The interrupt service routine is trivial, just printing a '.'
4922character, but this is just a demo program. The application can be
4923controlled by the following keys:
4924
4925 ? - print current values og the CPM Timer registers
4926 b - enable interrupts and start timer
4927 e - stop timer and disable interrupts
4928 q - quit application
4929
4930 => loads
4931 ## Ready for S-Record download ...
4932 ~>examples/timer.srec
4933 1 2 3 4 5 6 7 8 9 10 11 ...
4934 [file transfer complete]
4935 [connected]
4936 ## Start Addr = 0x00040004
4937
4938 => go 40004
4939 ## Starting application at 0x00040004 ...
4940 TIMERS=0xfff00980
4941 Using timer 1
4942 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4943
4944Hit 'b':
4945 [q, b, e, ?] Set interval 1000000 us
4946 Enabling timer
4947Hit '?':
4948 [q, b, e, ?] ........
4949 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4950Hit '?':
4951 [q, b, e, ?] .
4952 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4953Hit '?':
4954 [q, b, e, ?] .
4955 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4956Hit '?':
4957 [q, b, e, ?] .
4958 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4959Hit 'e':
4960 [q, b, e, ?] ...Stopping timer
4961Hit 'q':
4962 [q, b, e, ?] ## Application terminated, rc = 0x0
4963
4964
4965Minicom warning:
4966================
4967
4968Over time, many people have reported problems when trying to use the
4969"minicom" terminal emulation program for serial download. I (wd)
4970consider minicom to be broken, and recommend not to use it. Under
4971Unix, I recommend to use C-Kermit for general purpose use (and
4972especially for kermit binary protocol download ("loadb" command), and
e53515a2
KP
4973use "cu" for S-Record download ("loads" command). See
4974http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4975for help with kermit.
4976
2729af9d
WD
4977
4978Nevertheless, if you absolutely want to use it try adding this
4979configuration to your "File transfer protocols" section:
4980
4981 Name Program Name U/D FullScr IO-Red. Multi
4982 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4983 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4984
4985
4986NetBSD Notes:
4987=============
4988
4989Starting at version 0.9.2, U-Boot supports NetBSD both as host
4990(build U-Boot) and target system (boots NetBSD/mpc8xx).
4991
4992Building requires a cross environment; it is known to work on
4993NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4994need gmake since the Makefiles are not compatible with BSD make).
4995Note that the cross-powerpc package does not install include files;
4996attempting to build U-Boot will fail because <machine/ansi.h> is
4997missing. This file has to be installed and patched manually:
4998
4999 # cd /usr/pkg/cross/powerpc-netbsd/include
5000 # mkdir powerpc
5001 # ln -s powerpc machine
5002 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5003 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5004
5005Native builds *don't* work due to incompatibilities between native
5006and U-Boot include files.
5007
5008Booting assumes that (the first part of) the image booted is a
5009stage-2 loader which in turn loads and then invokes the kernel
5010proper. Loader sources will eventually appear in the NetBSD source
5011tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2a8af187 5012meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
2729af9d
WD
5013
5014
5015Implementation Internals:
5016=========================
5017
5018The following is not intended to be a complete description of every
5019implementation detail. However, it should help to understand the
5020inner workings of U-Boot and make it easier to port it to custom
5021hardware.
5022
5023
5024Initial Stack, Global Data:
5025---------------------------
5026
5027The implementation of U-Boot is complicated by the fact that U-Boot
5028starts running out of ROM (flash memory), usually without access to
5029system RAM (because the memory controller is not initialized yet).
5030This means that we don't have writable Data or BSS segments, and BSS
5031is not initialized as zero. To be able to get a C environment working
5032at all, we have to allocate at least a minimal stack. Implementation
5033options for this are defined and restricted by the CPU used: Some CPU
5034models provide on-chip memory (like the IMMR area on MPC8xx and
5035MPC826x processors), on others (parts of) the data cache can be
5036locked as (mis-) used as memory, etc.
5037
218ca724 5038 Chris Hallinan posted a good summary of these issues to the
0668236b 5039 U-Boot mailing list:
2729af9d
WD
5040
5041 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5042 From: "Chris Hallinan" <clh@net1plus.com>
5043 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5044 ...
5045
5046 Correct me if I'm wrong, folks, but the way I understand it
5047 is this: Using DCACHE as initial RAM for Stack, etc, does not
5048 require any physical RAM backing up the cache. The cleverness
5049 is that the cache is being used as a temporary supply of
5050 necessary storage before the SDRAM controller is setup. It's
11ccc33f 5051 beyond the scope of this list to explain the details, but you
2729af9d
WD
5052 can see how this works by studying the cache architecture and
5053 operation in the architecture and processor-specific manuals.
5054
5055 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5056 is another option for the system designer to use as an
11ccc33f 5057 initial stack/RAM area prior to SDRAM being available. Either
2729af9d
WD
5058 option should work for you. Using CS 4 should be fine if your
5059 board designers haven't used it for something that would
5060 cause you grief during the initial boot! It is frequently not
5061 used.
5062
6d0f6bcf 5063 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
2729af9d
WD
5064 with your processor/board/system design. The default value
5065 you will find in any recent u-boot distribution in
8a316c9b 5066 walnut.h should work for you. I'd set it to a value larger
2729af9d
WD
5067 than your SDRAM module. If you have a 64MB SDRAM module, set
5068 it above 400_0000. Just make sure your board has no resources
5069 that are supposed to respond to that address! That code in
5070 start.S has been around a while and should work as is when
5071 you get the config right.
5072
5073 -Chris Hallinan
5074 DS4.COM, Inc.
5075
5076It is essential to remember this, since it has some impact on the C
5077code for the initialization procedures:
5078
5079* Initialized global data (data segment) is read-only. Do not attempt
5080 to write it.
5081
b445bbb4 5082* Do not use any uninitialized global data (or implicitly initialized
2729af9d
WD
5083 as zero data - BSS segment) at all - this is undefined, initiali-
5084 zation is performed later (when relocating to RAM).
5085
5086* Stack space is very limited. Avoid big data buffers or things like
5087 that.
5088
5089Having only the stack as writable memory limits means we cannot use
b445bbb4 5090normal global data to share information between the code. But it
2729af9d
WD
5091turned out that the implementation of U-Boot can be greatly
5092simplified by making a global data structure (gd_t) available to all
5093functions. We could pass a pointer to this data as argument to _all_
5094functions, but this would bloat the code. Instead we use a feature of
5095the GCC compiler (Global Register Variables) to share the data: we
5096place a pointer (gd) to the global data into a register which we
5097reserve for this purpose.
5098
5099When choosing a register for such a purpose we are restricted by the
5100relevant (E)ABI specifications for the current architecture, and by
5101GCC's implementation.
5102
5103For PowerPC, the following registers have specific use:
5104 R1: stack pointer
e7670f6c 5105 R2: reserved for system use
2729af9d
WD
5106 R3-R4: parameter passing and return values
5107 R5-R10: parameter passing
5108 R13: small data area pointer
5109 R30: GOT pointer
5110 R31: frame pointer
5111
e6bee808
JT
5112 (U-Boot also uses R12 as internal GOT pointer. r12
5113 is a volatile register so r12 needs to be reset when
5114 going back and forth between asm and C)
2729af9d 5115
e7670f6c 5116 ==> U-Boot will use R2 to hold a pointer to the global data
2729af9d
WD
5117
5118 Note: on PPC, we could use a static initializer (since the
5119 address of the global data structure is known at compile time),
5120 but it turned out that reserving a register results in somewhat
5121 smaller code - although the code savings are not that big (on
5122 average for all boards 752 bytes for the whole U-Boot image,
5123 624 text + 127 data).
5124
5125On ARM, the following registers are used:
5126
5127 R0: function argument word/integer result
5128 R1-R3: function argument word
12eba1b4
JH
5129 R9: platform specific
5130 R10: stack limit (used only if stack checking is enabled)
2729af9d
WD
5131 R11: argument (frame) pointer
5132 R12: temporary workspace
5133 R13: stack pointer
5134 R14: link register
5135 R15: program counter
5136
12eba1b4
JH
5137 ==> U-Boot will use R9 to hold a pointer to the global data
5138
5139 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
2729af9d 5140
0df01fd3
TC
5141On Nios II, the ABI is documented here:
5142 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5143
5144 ==> U-Boot will use gp to hold a pointer to the global data
5145
5146 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5147 to access small data sections, so gp is free.
5148
afc1ce82
ML
5149On NDS32, the following registers are used:
5150
5151 R0-R1: argument/return
5152 R2-R5: argument
5153 R15: temporary register for assembler
5154 R16: trampoline register
5155 R28: frame pointer (FP)
5156 R29: global pointer (GP)
5157 R30: link register (LP)
5158 R31: stack pointer (SP)
5159 PC: program counter (PC)
5160
5161 ==> U-Boot will use R10 to hold a pointer to the global data
5162
d87080b7
WD
5163NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5164or current versions of GCC may "optimize" the code too much.
2729af9d
WD
5165
5166Memory Management:
5167------------------
5168
5169U-Boot runs in system state and uses physical addresses, i.e. the
5170MMU is not used either for address mapping nor for memory protection.
5171
5172The available memory is mapped to fixed addresses using the memory
5173controller. In this process, a contiguous block is formed for each
5174memory type (Flash, SDRAM, SRAM), even when it consists of several
5175physical memory banks.
5176
5177U-Boot is installed in the first 128 kB of the first Flash bank (on
5178TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5179booting and sizing and initializing DRAM, the code relocates itself
5180to the upper end of DRAM. Immediately below the U-Boot code some
6d0f6bcf 5181memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
2729af9d
WD
5182configuration setting]. Below that, a structure with global Board
5183Info data is placed, followed by the stack (growing downward).
5184
5185Additionally, some exception handler code is copied to the low 8 kB
5186of DRAM (0x00000000 ... 0x00001FFF).
5187
5188So a typical memory configuration with 16 MB of DRAM could look like
5189this:
5190
5191 0x0000 0000 Exception Vector code
5192 :
5193 0x0000 1FFF
5194 0x0000 2000 Free for Application Use
5195 :
5196 :
5197
5198 :
5199 :
5200 0x00FB FF20 Monitor Stack (Growing downward)
5201 0x00FB FFAC Board Info Data and permanent copy of global data
5202 0x00FC 0000 Malloc Arena
5203 :
5204 0x00FD FFFF
5205 0x00FE 0000 RAM Copy of Monitor Code
5206 ... eventually: LCD or video framebuffer
5207 ... eventually: pRAM (Protected RAM - unchanged by reset)
5208 0x00FF FFFF [End of RAM]
5209
5210
5211System Initialization:
5212----------------------
c609719b 5213
2729af9d 5214In the reset configuration, U-Boot starts at the reset entry point
11ccc33f 5215(on most PowerPC systems at address 0x00000100). Because of the reset
b445bbb4 5216configuration for CS0# this is a mirror of the on board Flash memory.
2729af9d
WD
5217To be able to re-map memory U-Boot then jumps to its link address.
5218To be able to implement the initialization code in C, a (small!)
5219initial stack is set up in the internal Dual Ported RAM (in case CPUs
2eb48ff7
HS
5220which provide such a feature like), or in a locked part of the data
5221cache. After that, U-Boot initializes the CPU core, the caches and
5222the SIU.
2729af9d
WD
5223
5224Next, all (potentially) available memory banks are mapped using a
5225preliminary mapping. For example, we put them on 512 MB boundaries
5226(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5227on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5228programmed for SDRAM access. Using the temporary configuration, a
5229simple memory test is run that determines the size of the SDRAM
5230banks.
5231
5232When there is more than one SDRAM bank, and the banks are of
5233different size, the largest is mapped first. For equal size, the first
5234bank (CS2#) is mapped first. The first mapping is always for address
52350x00000000, with any additional banks following immediately to create
5236contiguous memory starting from 0.
5237
5238Then, the monitor installs itself at the upper end of the SDRAM area
5239and allocates memory for use by malloc() and for the global Board
5240Info data; also, the exception vector code is copied to the low RAM
5241pages, and the final stack is set up.
5242
5243Only after this relocation will you have a "normal" C environment;
5244until that you are restricted in several ways, mostly because you are
5245running from ROM, and because the code will have to be relocated to a
5246new address in RAM.
5247
5248
5249U-Boot Porting Guide:
5250----------------------
c609719b 5251
2729af9d
WD
5252[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5253list, October 2002]
c609719b
WD
5254
5255
6c3fef28 5256int main(int argc, char *argv[])
2729af9d
WD
5257{
5258 sighandler_t no_more_time;
c609719b 5259
6c3fef28
JVB
5260 signal(SIGALRM, no_more_time);
5261 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
c609719b 5262
2729af9d 5263 if (available_money > available_manpower) {
6c3fef28 5264 Pay consultant to port U-Boot;
c609719b
WD
5265 return 0;
5266 }
5267
2729af9d
WD
5268 Download latest U-Boot source;
5269
0668236b 5270 Subscribe to u-boot mailing list;
2729af9d 5271
6c3fef28
JVB
5272 if (clueless)
5273 email("Hi, I am new to U-Boot, how do I get started?");
2729af9d
WD
5274
5275 while (learning) {
5276 Read the README file in the top level directory;
6c3fef28
JVB
5277 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5278 Read applicable doc/*.README;
2729af9d 5279 Read the source, Luke;
6c3fef28 5280 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
2729af9d
WD
5281 }
5282
6c3fef28
JVB
5283 if (available_money > toLocalCurrency ($2500))
5284 Buy a BDI3000;
5285 else
2729af9d 5286 Add a lot of aggravation and time;
2729af9d 5287
6c3fef28
JVB
5288 if (a similar board exists) { /* hopefully... */
5289 cp -a board/<similar> board/<myboard>
5290 cp include/configs/<similar>.h include/configs/<myboard>.h
5291 } else {
5292 Create your own board support subdirectory;
5293 Create your own board include/configs/<myboard>.h file;
5294 }
5295 Edit new board/<myboard> files
5296 Edit new include/configs/<myboard>.h
5297
5298 while (!accepted) {
5299 while (!running) {
5300 do {
5301 Add / modify source code;
5302 } until (compiles);
5303 Debug;
5304 if (clueless)
5305 email("Hi, I am having problems...");
5306 }
5307 Send patch file to the U-Boot email list;
5308 if (reasonable critiques)
5309 Incorporate improvements from email list code review;
5310 else
5311 Defend code as written;
2729af9d 5312 }
2729af9d
WD
5313
5314 return 0;
5315}
5316
5317void no_more_time (int sig)
5318{
5319 hire_a_guru();
5320}
5321
c609719b 5322
2729af9d
WD
5323Coding Standards:
5324-----------------
c609719b 5325
2729af9d 5326All contributions to U-Boot should conform to the Linux kernel
2c051651 5327coding style; see the file "Documentation/CodingStyle" and the script
7ca9296e 5328"scripts/Lindent" in your Linux kernel source directory.
2c051651
DZ
5329
5330Source files originating from a different project (for example the
5331MTD subsystem) are generally exempt from these guidelines and are not
b445bbb4 5332reformatted to ease subsequent migration to newer versions of those
2c051651
DZ
5333sources.
5334
5335Please note that U-Boot is implemented in C (and to some small parts in
5336Assembler); no C++ is used, so please do not use C++ style comments (//)
5337in your code.
c609719b 5338
2729af9d
WD
5339Please also stick to the following formatting rules:
5340- remove any trailing white space
7ca9296e 5341- use TAB characters for indentation and vertical alignment, not spaces
2729af9d 5342- make sure NOT to use DOS '\r\n' line feeds
7ca9296e 5343- do not add more than 2 consecutive empty lines to source files
2729af9d 5344- do not add trailing empty lines to source files
180d3f74 5345
2729af9d
WD
5346Submissions which do not conform to the standards may be returned
5347with a request to reformat the changes.
c609719b
WD
5348
5349
2729af9d
WD
5350Submitting Patches:
5351-------------------
c609719b 5352
2729af9d
WD
5353Since the number of patches for U-Boot is growing, we need to
5354establish some rules. Submissions which do not conform to these rules
5355may be rejected, even when they contain important and valuable stuff.
c609719b 5356
0d28f34b 5357Please see http://www.denx.de/wiki/U-Boot/Patches for details.
218ca724 5358
0668236b
WD
5359Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5360see http://lists.denx.de/mailman/listinfo/u-boot
5361
2729af9d
WD
5362When you send a patch, please include the following information with
5363it:
c609719b 5364
2729af9d
WD
5365* For bug fixes: a description of the bug and how your patch fixes
5366 this bug. Please try to include a way of demonstrating that the
5367 patch actually fixes something.
c609719b 5368
2729af9d
WD
5369* For new features: a description of the feature and your
5370 implementation.
c609719b 5371
2729af9d 5372* A CHANGELOG entry as plaintext (separate from the patch)
c609719b 5373
7207b366
RD
5374* For major contributions, add a MAINTAINERS file with your
5375 information and associated file and directory references.
c609719b 5376
27af930e
AA
5377* When you add support for a new board, don't forget to add a
5378 maintainer e-mail address to the boards.cfg file, too.
c609719b 5379
2729af9d
WD
5380* If your patch adds new configuration options, don't forget to
5381 document these in the README file.
c609719b 5382
218ca724
WD
5383* The patch itself. If you are using git (which is *strongly*
5384 recommended) you can easily generate the patch using the
7ca9296e 5385 "git format-patch". If you then use "git send-email" to send it to
218ca724
WD
5386 the U-Boot mailing list, you will avoid most of the common problems
5387 with some other mail clients.
5388
5389 If you cannot use git, use "diff -purN OLD NEW". If your version of
5390 diff does not support these options, then get the latest version of
5391 GNU diff.
c609719b 5392
218ca724
WD
5393 The current directory when running this command shall be the parent
5394 directory of the U-Boot source tree (i. e. please make sure that
5395 your patch includes sufficient directory information for the
5396 affected files).
6dff5529 5397
218ca724
WD
5398 We prefer patches as plain text. MIME attachments are discouraged,
5399 and compressed attachments must not be used.
c609719b 5400
2729af9d
WD
5401* If one logical set of modifications affects or creates several
5402 files, all these changes shall be submitted in a SINGLE patch file.
52f52c14 5403
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WD
5404* Changesets that contain different, unrelated modifications shall be
5405 submitted as SEPARATE patches, one patch per changeset.
8bde7f77 5406
52f52c14 5407
2729af9d 5408Notes:
c609719b 5409
6de80f21 5410* Before sending the patch, run the buildman script on your patched
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WD
5411 source tree and make sure that no errors or warnings are reported
5412 for any of the boards.
c609719b 5413
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WD
5414* Keep your modifications to the necessary minimum: A patch
5415 containing several unrelated changes or arbitrary reformats will be
5416 returned with a request to re-formatting / split it.
c609719b 5417
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WD
5418* If you modify existing code, make sure that your new code does not
5419 add to the memory footprint of the code ;-) Small is beautiful!
5420 When adding new features, these should compile conditionally only
5421 (using #ifdef), and the resulting code with the new feature
5422 disabled must not need more memory than the old code without your
5423 modification.
90dc6704 5424
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5425* Remember that there is a size limit of 100 kB per message on the
5426 u-boot mailing list. Bigger patches will be moderated. If they are
5427 reasonable and not too big, they will be acknowledged. But patches
5428 bigger than the size limit should be avoided.