blob: 5549849d29919619af6a86644bc84334edfa233b [file] [log] [blame]
Tom Rini83d290c2018-05-06 17:58:06 -04001# SPDX-License-Identifier: GPL-2.0+
wdenkc6097192002-11-03 00:24:07 +00002#
Wolfgang Denkeca3aeb2013-06-21 10:22:36 +02003# (C) Copyright 2000 - 2013
wdenkc6097192002-11-03 00:24:07 +00004# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
wdenkc6097192002-11-03 00:24:07 +00005
6Summary:
7========
8
wdenk24ee89b2002-11-03 17:56:27 +00009This directory contains the source code for U-Boot, a boot loader for
wdenke86e5a02004-10-17 21:12:06 +000010Embedded boards based on PowerPC, ARM, MIPS and several other
11processors, which can be installed in a boot ROM and used to
12initialize and test the hardware or to download and run application
13code.
wdenkc6097192002-11-03 00:24:07 +000014
15The development of U-Boot is closely related to Linux: some parts of
wdenk24ee89b2002-11-03 17:56:27 +000016the source code originate in the Linux source tree, we have some
17header files in common, and special provision has been made to
wdenkc6097192002-11-03 00:24:07 +000018support booting of Linux images.
19
20Some attention has been paid to make this software easily
21configurable and extendable. For instance, all monitor commands are
22implemented with the same call interface, so that it's very easy to
23add new commands. Also, instead of permanently adding rarely used
24code (for instance hardware test utilities) to the monitor, you can
25load and run it dynamically.
26
27
28Status:
29=======
30
31In general, all boards for which a configuration option exists in the
wdenk24ee89b2002-11-03 17:56:27 +000032Makefile have been tested to some extent and can be considered
wdenkc6097192002-11-03 00:24:07 +000033"working". In fact, many of them are used in production systems.
34
Robert P. J. Day7207b362015-12-19 07:16:10 -050035In case of problems see the CHANGELOG file to find out who contributed
36the specific port. In addition, there are various MAINTAINERS files
37scattered throughout the U-Boot source identifying the people or
38companies responsible for various boards and subsystems.
wdenkc6097192002-11-03 00:24:07 +000039
Robert P. J. Day7207b362015-12-19 07:16:10 -050040Note: As of August, 2010, there is no longer a CHANGELOG file in the
41actual U-Boot source tree; however, it can be created dynamically
42from the Git log using:
Robert P. J. Dayadb9d852012-11-14 02:03:20 +000043
44 make CHANGELOG
45
wdenkc6097192002-11-03 00:24:07 +000046
47Where to get help:
48==================
49
wdenk24ee89b2002-11-03 17:56:27 +000050In case you have questions about, problems with or contributions for
Robert P. J. Day7207b362015-12-19 07:16:10 -050051U-Boot, you should send a message to the U-Boot mailing list at
Peter Tyser0c325652008-09-10 09:18:34 -050052<u-boot@lists.denx.de>. There is also an archive of previous traffic
53on the mailing list - please search the archive before asking FAQ's.
Naoki Hayama6681bbb2020-10-08 13:16:18 +090054Please see https://lists.denx.de/pipermail/u-boot and
55https://marc.info/?l=u-boot
wdenkc6097192002-11-03 00:24:07 +000056
Wolfgang Denk218ca722008-03-26 10:40:12 +010057Where to get source code:
58=========================
59
Robert P. J. Day7207b362015-12-19 07:16:10 -050060The U-Boot source code is maintained in the Git repository at
Heinrich Schuchardta3bbd0b2021-02-24 13:19:04 +010061https://source.denx.de/u-boot/u-boot.git ; you can browse it online at
62https://source.denx.de/u-boot/u-boot
Wolfgang Denk218ca722008-03-26 10:40:12 +010063
Naoki Hayamac4bd51e2020-10-08 13:16:25 +090064The "Tags" links on this page allow you to download tarballs of
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020065any version you might be interested in. Official releases are also
Naoki Hayamac4bd51e2020-10-08 13:16:25 +090066available from the DENX file server through HTTPS or FTP.
67https://ftp.denx.de/pub/u-boot/
68ftp://ftp.denx.de/pub/u-boot/
Wolfgang Denk218ca722008-03-26 10:40:12 +010069
70
wdenkc6097192002-11-03 00:24:07 +000071Where we come from:
72===================
73
74- start from 8xxrom sources
Naoki Hayama047f6ec2020-10-08 13:17:16 +090075- create PPCBoot project (https://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000076- clean up code
77- make it easier to add custom boards
78- make it possible to add other [PowerPC] CPUs
79- extend functions, especially:
80 * Provide extended interface to Linux boot loader
81 * S-Record download
82 * network boot
Simon Glass9e5616d2019-08-01 09:47:14 -060083 * ATA disk / SCSI ... boot
Naoki Hayama047f6ec2020-10-08 13:17:16 +090084- create ARMBoot project (https://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000085- add other CPU families (starting with ARM)
Naoki Hayama047f6ec2020-10-08 13:17:16 +090086- create U-Boot project (https://sourceforge.net/projects/u-boot)
87- current project page: see https://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000088
89
90Names and Spelling:
91===================
92
93The "official" name of this project is "Das U-Boot". The spelling
94"U-Boot" shall be used in all written text (documentation, comments
95in source files etc.). Example:
96
97 This is the README file for the U-Boot project.
98
99File names etc. shall be based on the string "u-boot". Examples:
100
101 include/asm-ppc/u-boot.h
102
103 #include <asm/u-boot.h>
104
105Variable names, preprocessor constants etc. shall be either based on
106the string "u_boot" or on "U_BOOT". Example:
107
108 U_BOOT_VERSION u_boot_logo
109 IH_OS_U_BOOT u_boot_hush_start
wdenkc6097192002-11-03 00:24:07 +0000110
111
wdenk93f19cc2002-12-17 17:55:09 +0000112Versioning:
113===========
114
Thomas Weber360d8832010-09-28 08:06:25 +0200115Starting with the release in October 2008, the names of the releases
116were changed from numerical release numbers without deeper meaning
117into a time stamp based numbering. Regular releases are identified by
118names consisting of the calendar year and month of the release date.
119Additional fields (if present) indicate release candidates or bug fix
120releases in "stable" maintenance trees.
wdenk93f19cc2002-12-17 17:55:09 +0000121
Thomas Weber360d8832010-09-28 08:06:25 +0200122Examples:
Wolfgang Denkc0f40852011-10-26 10:21:21 +0000123 U-Boot v2009.11 - Release November 2009
Thomas Weber360d8832010-09-28 08:06:25 +0200124 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
Jelle van der Waa0de21ec2016-10-30 17:30:30 +0100125 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
wdenk93f19cc2002-12-17 17:55:09 +0000126
127
wdenkc6097192002-11-03 00:24:07 +0000128Directory Hierarchy:
129====================
130
Simon Glass6e73ed02021-07-10 21:14:21 -0600131/arch Architecture-specific files
Masahiro Yamada6eae68e2014-03-07 18:02:02 +0900132 /arc Files generic to ARC architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500133 /arm Files generic to ARM architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500134 /m68k Files generic to m68k architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500135 /microblaze Files generic to microblaze architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500136 /mips Files generic to MIPS architecture
Macpaul Linafc1ce82011-10-19 20:41:11 +0000137 /nds32 Files generic to NDS32 architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500138 /nios2 Files generic to Altera NIOS2 architecture
Stefan Roesea47a12b2010-04-15 16:07:28 +0200139 /powerpc Files generic to PowerPC architecture
Rick Chen3fafced2017-12-26 13:55:59 +0800140 /riscv Files generic to RISC-V architecture
Robert P. J. Day7207b362015-12-19 07:16:10 -0500141 /sandbox Files generic to HW-independent "sandbox"
Peter Tyser8d321b82010-04-12 22:28:21 -0500142 /sh Files generic to SH architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400143 /x86 Files generic to x86 architecture
Naoki Hayamae4eb3132020-10-08 13:16:38 +0900144 /xtensa Files generic to Xtensa architecture
Simon Glass6e73ed02021-07-10 21:14:21 -0600145/api Machine/arch-independent API for external apps
146/board Board-dependent files
Simon Glass19a91f22021-10-14 12:47:54 -0600147/boot Support for images and booting
Xu Ziyuan740f7e52016-08-26 19:54:49 +0800148/cmd U-Boot commands functions
Simon Glass6e73ed02021-07-10 21:14:21 -0600149/common Misc architecture-independent functions
Robert P. J. Day7207b362015-12-19 07:16:10 -0500150/configs Board default configuration files
Peter Tyser8d321b82010-04-12 22:28:21 -0500151/disk Code for disk drive partition handling
Simon Glass6e73ed02021-07-10 21:14:21 -0600152/doc Documentation (a mix of ReST and READMEs)
153/drivers Device drivers
154/dts Makefile for building internal U-Boot fdt.
155/env Environment support
Peter Tyser8d321b82010-04-12 22:28:21 -0500156/examples Example code for standalone applications, etc.
157/fs Filesystem code (cramfs, ext2, jffs2, etc.)
158/include Header Files
Robert P. J. Day7207b362015-12-19 07:16:10 -0500159/lib Library routines generic to all architectures
160/Licenses Various license files
Peter Tyser8d321b82010-04-12 22:28:21 -0500161/net Networking code
162/post Power On Self Test
Robert P. J. Day7207b362015-12-19 07:16:10 -0500163/scripts Various build scripts and Makefiles
164/test Various unit test files
Simon Glass6e73ed02021-07-10 21:14:21 -0600165/tools Tools to build and sign FIT images, etc.
wdenkc6097192002-11-03 00:24:07 +0000166
wdenkc6097192002-11-03 00:24:07 +0000167Software Configuration:
168=======================
169
170Configuration is usually done using C preprocessor defines; the
171rationale behind that is to avoid dead code whenever possible.
172
173There are two classes of configuration variables:
174
175* Configuration _OPTIONS_:
176 These are selectable by the user and have names beginning with
177 "CONFIG_".
178
179* Configuration _SETTINGS_:
180 These depend on the hardware etc. and should not be meddled with if
181 you don't know what you're doing; they have names beginning with
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200182 "CONFIG_SYS_".
wdenkc6097192002-11-03 00:24:07 +0000183
Robert P. J. Day7207b362015-12-19 07:16:10 -0500184Previously, all configuration was done by hand, which involved creating
185symbolic links and editing configuration files manually. More recently,
186U-Boot has added the Kbuild infrastructure used by the Linux kernel,
187allowing you to use the "make menuconfig" command to configure your
188build.
wdenkc6097192002-11-03 00:24:07 +0000189
190
191Selection of Processor Architecture and Board Type:
192---------------------------------------------------
193
194For all supported boards there are ready-to-use default
Holger Freytherab584d62014-08-04 09:26:05 +0200195configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000196
197Example: For a TQM823L module type:
198
199 cd u-boot
Holger Freytherab584d62014-08-04 09:26:05 +0200200 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000201
Robert P. J. Day7207b362015-12-19 07:16:10 -0500202Note: If you're looking for the default configuration file for a board
203you're sure used to be there but is now missing, check the file
204doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000205
Simon Glass75b3c3a2014-03-22 17:12:59 -0600206Sandbox Environment:
207--------------------
208
209U-Boot can be built natively to run on a Linux host using the 'sandbox'
210board. This allows feature development which is not board- or architecture-
211specific to be undertaken on a native platform. The sandbox is also used to
212run some of U-Boot's tests.
213
Naoki Hayamabbb140e2020-10-08 13:16:58 +0900214See doc/arch/sandbox.rst for more details.
Simon Glass75b3c3a2014-03-22 17:12:59 -0600215
216
Simon Glassdb910352015-03-03 08:03:00 -0700217Board Initialisation Flow:
218--------------------------
219
220This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day7207b362015-12-19 07:16:10 -0500221SPL and U-Boot proper (i.e. they both follow the same rules).
Simon Glassdb910352015-03-03 08:03:00 -0700222
Robert P. J. Day7207b362015-12-19 07:16:10 -0500223Note: "SPL" stands for "Secondary Program Loader," which is explained in
224more detail later in this file.
225
226At present, SPL mostly uses a separate code path, but the function names
227and roles of each function are the same. Some boards or architectures
228may not conform to this. At least most ARM boards which use
229CONFIG_SPL_FRAMEWORK conform to this.
230
231Execution typically starts with an architecture-specific (and possibly
232CPU-specific) start.S file, such as:
233
234 - arch/arm/cpu/armv7/start.S
235 - arch/powerpc/cpu/mpc83xx/start.S
236 - arch/mips/cpu/start.S
237
238and so on. From there, three functions are called; the purpose and
239limitations of each of these functions are described below.
Simon Glassdb910352015-03-03 08:03:00 -0700240
241lowlevel_init():
242 - purpose: essential init to permit execution to reach board_init_f()
243 - no global_data or BSS
244 - there is no stack (ARMv7 may have one but it will soon be removed)
245 - must not set up SDRAM or use console
246 - must only do the bare minimum to allow execution to continue to
247 board_init_f()
248 - this is almost never needed
249 - return normally from this function
250
251board_init_f():
252 - purpose: set up the machine ready for running board_init_r():
253 i.e. SDRAM and serial UART
254 - global_data is available
255 - stack is in SRAM
256 - BSS is not available, so you cannot use global/static variables,
257 only stack variables and global_data
258
259 Non-SPL-specific notes:
260 - dram_init() is called to set up DRAM. If already done in SPL this
261 can do nothing
262
263 SPL-specific notes:
264 - you can override the entire board_init_f() function with your own
265 version as needed.
266 - preloader_console_init() can be called here in extremis
267 - should set up SDRAM, and anything needed to make the UART work
Naoki Hayama499696e2020-09-24 15:57:19 +0900268 - there is no need to clear BSS, it will be done by crt0.S
Andreas Dannenberg14254652019-08-08 12:54:49 -0500269 - for specific scenarios on certain architectures an early BSS *can*
270 be made available (via CONFIG_SPL_EARLY_BSS by moving the clearing
271 of BSS prior to entering board_init_f()) but doing so is discouraged.
272 Instead it is strongly recommended to architect any code changes
273 or additions such to not depend on the availability of BSS during
274 board_init_f() as indicated in other sections of this README to
275 maintain compatibility and consistency across the entire code base.
Simon Glassdb910352015-03-03 08:03:00 -0700276 - must return normally from this function (don't call board_init_r()
277 directly)
278
279Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
280this point the stack and global_data are relocated to below
281CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
282memory.
283
284board_init_r():
285 - purpose: main execution, common code
286 - global_data is available
287 - SDRAM is available
288 - BSS is available, all static/global variables can be used
289 - execution eventually continues to main_loop()
290
291 Non-SPL-specific notes:
292 - U-Boot is relocated to the top of memory and is now running from
293 there.
294
295 SPL-specific notes:
296 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
297 CONFIG_SPL_STACK_R_ADDR points into SDRAM
298 - preloader_console_init() can be called here - typically this is
Ley Foon Tan0680f1b2017-05-03 17:13:32 +0800299 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
Simon Glassdb910352015-03-03 08:03:00 -0700300 spl_board_init() function containing this call
301 - loads U-Boot or (in falcon mode) Linux
302
303
wdenkc6097192002-11-03 00:24:07 +0000304Configuration Options:
305----------------------
306
307Configuration depends on the combination of board and CPU type; all
308such information is kept in a configuration file
309"include/configs/<board_name>.h".
310
311Example: For a TQM823L module, all configuration settings are in
312"include/configs/TQM823L.h".
313
314
wdenk7f6c2cb2002-11-10 22:06:23 +0000315Many of the options are named exactly as the corresponding Linux
316kernel configuration options. The intention is to make it easier to
317build a config tool - later.
318
Ashish Kumar63b23162017-08-11 11:09:14 +0530319- ARM Platform Bus Type(CCI):
320 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
321 provides full cache coherency between two clusters of multi-core
322 CPUs and I/O coherency for devices and I/O masters
323
324 CONFIG_SYS_FSL_HAS_CCI400
325
326 Defined For SoC that has cache coherent interconnect
327 CCN-400
wdenk7f6c2cb2002-11-10 22:06:23 +0000328
Ashish Kumarc055cee2017-08-18 10:54:36 +0530329 CONFIG_SYS_FSL_HAS_CCN504
330
331 Defined for SoC that has cache coherent interconnect CCN-504
332
wdenkc6097192002-11-03 00:24:07 +0000333The following options need to be configured:
334
Kim Phillips26281142007-08-10 13:28:25 -0500335- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000336
Kim Phillips26281142007-08-10 13:28:25 -0500337- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk6ccec442006-10-24 14:42:37 +0200338
Kumar Gala66412c62011-02-18 05:40:54 -0600339- 85xx CPU Options:
York Sunffd06e02012-10-08 07:44:30 +0000340 CONFIG_SYS_PPC64
341
342 Specifies that the core is a 64-bit PowerPC implementation (implements
343 the "64" category of the Power ISA). This is necessary for ePAPR
344 compliance, among other possible reasons.
345
Kumar Gala66412c62011-02-18 05:40:54 -0600346 CONFIG_SYS_FSL_TBCLK_DIV
347
348 Defines the core time base clock divider ratio compared to the
349 system clock. On most PQ3 devices this is 8, on newer QorIQ
350 devices it can be 16 or 32. The ratio varies from SoC to Soc.
351
Kumar Gala8f290842011-05-20 00:39:21 -0500352 CONFIG_SYS_FSL_PCIE_COMPAT
353
354 Defines the string to utilize when trying to match PCIe device
355 tree nodes for the given platform.
356
Scott Wood33eee332012-08-14 10:14:53 +0000357 CONFIG_SYS_FSL_ERRATUM_A004510
358
359 Enables a workaround for erratum A004510. If set,
360 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
361 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
362
363 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
364 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
365
366 Defines one or two SoC revisions (low 8 bits of SVR)
367 for which the A004510 workaround should be applied.
368
369 The rest of SVR is either not relevant to the decision
370 of whether the erratum is present (e.g. p2040 versus
371 p2041) or is implied by the build target, which controls
372 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
373
374 See Freescale App Note 4493 for more information about
375 this erratum.
376
Prabhakar Kushwaha74fa22e2013-04-16 13:27:44 +0530377 CONFIG_A003399_NOR_WORKAROUND
378 Enables a workaround for IFC erratum A003399. It is only
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800379 required during NOR boot.
Prabhakar Kushwaha74fa22e2013-04-16 13:27:44 +0530380
Prabhakar Kushwaha9f074e62014-10-29 22:33:09 +0530381 CONFIG_A008044_WORKAROUND
382 Enables a workaround for T1040/T1042 erratum A008044. It is only
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800383 required during NAND boot and valid for Rev 1.0 SoC revision
Prabhakar Kushwaha9f074e62014-10-29 22:33:09 +0530384
Scott Wood33eee332012-08-14 10:14:53 +0000385 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
386
387 This is the value to write into CCSR offset 0x18600
388 according to the A004510 workaround.
389
Priyanka Jain64501c62013-07-02 09:21:04 +0530390 CONFIG_SYS_FSL_DSP_DDR_ADDR
391 This value denotes start offset of DDR memory which is
392 connected exclusively to the DSP cores.
393
Priyanka Jain765b0bd2013-04-04 09:31:54 +0530394 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
395 This value denotes start offset of M2 memory
396 which is directly connected to the DSP core.
397
Priyanka Jain64501c62013-07-02 09:21:04 +0530398 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
399 This value denotes start offset of M3 memory which is directly
400 connected to the DSP core.
401
Priyanka Jain765b0bd2013-04-04 09:31:54 +0530402 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
403 This value denotes start offset of DSP CCSR space.
404
Priyanka Jainb1359912013-12-17 14:25:52 +0530405 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
406 Single Source Clock is clocking mode present in some of FSL SoC's.
407 In this mode, a single differential clock is used to supply
408 clocks to the sysclock, ddrclock and usbclock.
409
Aneesh Bansalfb4a2402014-03-18 23:40:26 +0530410 CONFIG_SYS_CPC_REINIT_F
411 This CONFIG is defined when the CPC is configured as SRAM at the
Bin Menga1875592016-02-05 19:30:11 -0800412 time of U-Boot entry and is required to be re-initialized.
Aneesh Bansalfb4a2402014-03-18 23:40:26 +0530413
Tang Yuantianaade2002014-04-17 15:33:46 +0800414 CONFIG_DEEP_SLEEP
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800415 Indicates this SoC supports deep sleep feature. If deep sleep is
Tang Yuantianaade2002014-04-17 15:33:46 +0800416 supported, core will start to execute uboot when wakes up.
417
Daniel Schwierzeck6cb461b2012-04-02 02:57:56 +0000418- Generic CPU options:
419 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
420
421 Defines the endianess of the CPU. Implementation of those
422 values is arch specific.
423
York Sun5614e712013-09-30 09:22:09 -0700424 CONFIG_SYS_FSL_DDR
425 Freescale DDR driver in use. This type of DDR controller is
Tom Rini1c588572021-05-14 21:34:26 -0400426 found in mpc83xx, mpc85xx as well as some ARM core SoCs.
York Sun5614e712013-09-30 09:22:09 -0700427
428 CONFIG_SYS_FSL_DDR_ADDR
429 Freescale DDR memory-mapped register base.
430
431 CONFIG_SYS_FSL_DDR_EMU
432 Specify emulator support for DDR. Some DDR features such as
433 deskew training are not available.
434
435 CONFIG_SYS_FSL_DDRC_GEN1
436 Freescale DDR1 controller.
437
438 CONFIG_SYS_FSL_DDRC_GEN2
439 Freescale DDR2 controller.
440
441 CONFIG_SYS_FSL_DDRC_GEN3
442 Freescale DDR3 controller.
443
York Sun34e026f2014-03-27 17:54:47 -0700444 CONFIG_SYS_FSL_DDRC_GEN4
445 Freescale DDR4 controller.
446
York Sun9ac4ffb2013-09-30 14:20:51 -0700447 CONFIG_SYS_FSL_DDRC_ARM_GEN3
448 Freescale DDR3 controller for ARM-based SoCs.
449
York Sun5614e712013-09-30 09:22:09 -0700450 CONFIG_SYS_FSL_DDR1
451 Board config to use DDR1. It can be enabled for SoCs with
452 Freescale DDR1 or DDR2 controllers, depending on the board
453 implemetation.
454
455 CONFIG_SYS_FSL_DDR2
Robert P. J. Day62a3b7d2016-07-15 13:44:45 -0400456 Board config to use DDR2. It can be enabled for SoCs with
York Sun5614e712013-09-30 09:22:09 -0700457 Freescale DDR2 or DDR3 controllers, depending on the board
458 implementation.
459
460 CONFIG_SYS_FSL_DDR3
461 Board config to use DDR3. It can be enabled for SoCs with
York Sun34e026f2014-03-27 17:54:47 -0700462 Freescale DDR3 or DDR3L controllers.
463
464 CONFIG_SYS_FSL_DDR3L
465 Board config to use DDR3L. It can be enabled for SoCs with
466 DDR3L controllers.
467
Prabhakar Kushwaha1b4175d2014-01-18 12:28:30 +0530468 CONFIG_SYS_FSL_IFC_BE
469 Defines the IFC controller register space as Big Endian
470
471 CONFIG_SYS_FSL_IFC_LE
472 Defines the IFC controller register space as Little Endian
473
Prabhakar Kushwaha1c407072017-02-02 15:01:26 +0530474 CONFIG_SYS_FSL_IFC_CLK_DIV
475 Defines divider of platform clock(clock input to IFC controller).
476
Prabhakar Kushwahaadd63f92017-02-02 15:02:00 +0530477 CONFIG_SYS_FSL_LBC_CLK_DIV
478 Defines divider of platform clock(clock input to eLBC controller).
479
York Sun4e5b1bd2014-02-10 13:59:42 -0800480 CONFIG_SYS_FSL_DDR_BE
481 Defines the DDR controller register space as Big Endian
482
483 CONFIG_SYS_FSL_DDR_LE
484 Defines the DDR controller register space as Little Endian
485
York Sun6b9e3092014-02-10 13:59:43 -0800486 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
487 Physical address from the view of DDR controllers. It is the
488 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
489 it could be different for ARM SoCs.
490
York Sun6b1e1252014-02-10 13:59:44 -0800491 CONFIG_SYS_FSL_DDR_INTLV_256B
492 DDR controller interleaving on 256-byte. This is a special
493 interleaving mode, handled by Dickens for Freescale layerscape
494 SoCs with ARM core.
495
York Sun1d71efb2014-08-01 15:51:00 -0700496 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
497 Number of controllers used as main memory.
498
499 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
500 Number of controllers used for other than main memory.
501
Prabhakar Kushwaha44937212015-11-09 16:42:07 +0530502 CONFIG_SYS_FSL_HAS_DP_DDR
503 Defines the SoC has DP-DDR used for DPAA.
504
Ruchika Gupta028dbb82014-09-09 11:50:31 +0530505 CONFIG_SYS_FSL_SEC_BE
506 Defines the SEC controller register space as Big Endian
507
508 CONFIG_SYS_FSL_SEC_LE
509 Defines the SEC controller register space as Little Endian
510
Daniel Schwierzeck92bbd642011-07-27 13:22:39 +0200511- MIPS CPU options:
512 CONFIG_SYS_INIT_SP_OFFSET
513
514 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
515 pointer. This is needed for the temporary stack before
516 relocation.
517
Daniel Schwierzeck92bbd642011-07-27 13:22:39 +0200518 CONFIG_XWAY_SWAP_BYTES
519
520 Enable compilation of tools/xway-swap-bytes needed for Lantiq
521 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
522 be swapped if a flash programmer is used.
523
Christian Rieschb67d8812012-02-02 00:44:39 +0000524- ARM options:
525 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
526
527 Select high exception vectors of the ARM core, e.g., do not
528 clear the V bit of the c1 register of CP15.
529
York Sun207774b2015-03-20 19:28:08 -0700530 COUNTER_FREQUENCY
531 Generic timer clock source frequency.
532
533 COUNTER_FREQUENCY_REAL
534 Generic timer clock source frequency if the real clock is
535 different from COUNTER_FREQUENCY, and can only be determined
536 at run time.
537
Stephen Warren73c38932015-01-19 16:25:52 -0700538- Tegra SoC options:
539 CONFIG_TEGRA_SUPPORT_NON_SECURE
540
541 Support executing U-Boot in non-secure (NS) mode. Certain
542 impossible actions will be skipped if the CPU is in NS mode,
543 such as ARM architectural timer initialization.
544
wdenk5da627a2003-10-09 20:09:04 +0000545- Linux Kernel Interface:
wdenk5da627a2003-10-09 20:09:04 +0000546 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
547
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800548 When transferring memsize parameter to Linux, some versions
wdenk5da627a2003-10-09 20:09:04 +0000549 expect it to be in bytes, others in MB.
550 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
551
Gerald Van Barenfec6d9e2008-06-03 20:34:45 -0400552 CONFIG_OF_LIBFDT
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200553
554 New kernel versions are expecting firmware settings to be
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400555 passed using flattened device trees (based on open firmware
556 concepts).
557
558 CONFIG_OF_LIBFDT
559 * New libfdt-based support
560 * Adds the "fdt" command
Kim Phillips3bb342f2007-08-10 14:34:14 -0500561 * The bootm command automatically updates the fdt
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400562
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200563 OF_TBCLK - The timebase frequency.
564
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200565 boards with QUICC Engines require OF_QE to set UCC MAC
566 addresses
Kim Phillips3bb342f2007-08-10 14:34:14 -0500567
Simon Glassc654b512014-10-23 18:58:54 -0600568 CONFIG_OF_SYSTEM_SETUP
569
570 Other code has addition modification that it wants to make
571 to the flat device tree before handing it off to the kernel.
572 This causes ft_system_setup() to be called before booting
573 the kernel.
574
Heiko Schocher3887c3f2009-09-23 07:56:08 +0200575 CONFIG_OF_IDE_FIXUP
576
577 U-Boot can detect if an IDE device is present or not.
578 If not, and this new config option is activated, U-Boot
579 removes the ATA node from the DTS before booting Linux,
580 so the Linux IDE driver does not probe the device and
581 crash. This is needed for buggy hardware (uc101) where
582 no pull down resistor is connected to the signal IDE5V_DD7.
583
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100584- vxWorks boot parameters:
585
586 bootvx constructs a valid bootline using the following
Bin Meng9e98b7e2015-10-07 20:19:17 -0700587 environments variables: bootdev, bootfile, ipaddr, netmask,
588 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100589 It loads the vxWorks image pointed bootfile.
590
Naoki Hayama81a05d92020-10-08 13:17:08 +0900591 Note: If a "bootargs" environment is defined, it will override
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100592 the defaults discussed just above.
593
Aneesh V93bc2192011-06-16 23:30:51 +0000594- Cache Configuration for ARM:
595 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
596 controller
597 CONFIG_SYS_PL310_BASE - Physical base address of PL310
598 controller register space
599
wdenk6705d812004-08-02 23:22:59 +0000600- Serial Ports:
wdenk6705d812004-08-02 23:22:59 +0000601 CONFIG_PL011_CLOCK
602
603 If you have Amba PrimeCell PL011 UARTs, set this variable to
604 the clock speed of the UARTs.
605
606 CONFIG_PL01x_PORTS
607
608 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
609 define this to a list of base addresses for each (supported)
610 port. See e.g. include/configs/versatile.h
611
Karicheri, Muralidharand57dee52014-04-09 15:38:46 -0400612 CONFIG_SERIAL_HW_FLOW_CONTROL
613
614 Define this variable to enable hw flow control in serial driver.
615 Current user of this option is drivers/serial/nsl16550.c driver
wdenk6705d812004-08-02 23:22:59 +0000616
wdenkc6097192002-11-03 00:24:07 +0000617- Serial Download Echo Mode:
618 CONFIG_LOADS_ECHO
619 If defined to 1, all characters received during a
620 serial download (using the "loads" command) are
621 echoed back. This might be needed by some terminal
622 emulations (like "cu"), but may as well just take
623 time on others. This setting #define's the initial
624 value of the "loads_echo" environment variable.
625
Simon Glass302a6482016-03-13 19:07:28 -0600626- Removal of commands
627 If no commands are needed to boot, you can disable
628 CONFIG_CMDLINE to remove them. In this case, the command line
629 will not be available, and when U-Boot wants to execute the
630 boot command (on start-up) it will call board_run_command()
631 instead. This can reduce image size significantly for very
632 simple boot procedures.
633
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000634- Regular expression support:
635 CONFIG_REGEX
Wolfgang Denk93e14592013-10-04 17:43:24 +0200636 If this variable is defined, U-Boot is linked against
637 the SLRE (Super Light Regular Expression) library,
638 which adds regex support to some commands, as for
639 example "env grep" and "setexpr".
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000640
wdenkc6097192002-11-03 00:24:07 +0000641- Watchdog:
Rasmus Villemoes933ada52021-04-14 09:18:22 +0200642 CONFIG_SYS_WATCHDOG_FREQ
643 Some platforms automatically call WATCHDOG_RESET()
644 from the timer interrupt handler every
645 CONFIG_SYS_WATCHDOG_FREQ interrupts. If not set by the
646 board configuration file, a default of CONFIG_SYS_HZ/2
647 (i.e. 500) is used. Setting CONFIG_SYS_WATCHDOG_FREQ
648 to 0 disables calling WATCHDOG_RESET() from the timer
649 interrupt.
650
wdenkc6097192002-11-03 00:24:07 +0000651- Real-Time Clock:
652
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500653 When CONFIG_CMD_DATE is selected, the type of the RTC
wdenkc6097192002-11-03 00:24:07 +0000654 has to be selected, too. Define exactly one of the
655 following options:
656
wdenkc6097192002-11-03 00:24:07 +0000657 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
Fabio Estevam4e8b7542011-10-24 06:44:15 +0000658 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
wdenkc6097192002-11-03 00:24:07 +0000659 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1cb8e982003-03-06 21:55:29 +0000660 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000661 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk7f70e852003-05-20 14:25:27 +0000662 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
Markus Niebel412921d2014-07-21 11:06:16 +0200663 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
wdenk3bac3512003-03-12 10:41:04 +0000664 CONFIG_RTC_DS164x - use Dallas DS164x RTC
Tor Krill9536dfc2008-03-15 15:40:26 +0100665 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
wdenk4c0d4c32004-06-09 17:34:58 +0000666 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Chris Packham2bd3cab2017-05-30 12:03:33 +1200667 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
Heiko Schocher71d19f32011-03-28 09:24:22 +0200668 CONFIG_SYS_RV3029_TCR - enable trickle charger on
669 RV3029 RTC.
wdenkc6097192002-11-03 00:24:07 +0000670
wdenkb37c7e52003-06-30 16:24:52 +0000671 Note that if the RTC uses I2C, then the I2C interface
672 must also be configured. See I2C Support, below.
673
Peter Tysere92739d2008-12-17 16:36:21 -0600674- GPIO Support:
675 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
Peter Tysere92739d2008-12-17 16:36:21 -0600676
Chris Packham5dec49c2010-12-19 10:12:13 +0000677 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
678 chip-ngpio pairs that tell the PCA953X driver the number of
679 pins supported by a particular chip.
680
Peter Tysere92739d2008-12-17 16:36:21 -0600681 Note that if the GPIO device uses I2C, then the I2C interface
682 must also be configured. See I2C Support, below.
683
Simon Glassaa532332014-06-11 23:29:41 -0600684- I/O tracing:
685 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
686 accesses and can checksum them or write a list of them out
687 to memory. See the 'iotrace' command for details. This is
688 useful for testing device drivers since it can confirm that
689 the driver behaves the same way before and after a code
690 change. Currently this is supported on sandbox and arm. To
691 add support for your architecture, add '#include <iotrace.h>'
692 to the bottom of arch/<arch>/include/asm/io.h and test.
693
694 Example output from the 'iotrace stats' command is below.
695 Note that if the trace buffer is exhausted, the checksum will
696 still continue to operate.
697
698 iotrace is enabled
699 Start: 10000000 (buffer start address)
700 Size: 00010000 (buffer size)
701 Offset: 00000120 (current buffer offset)
702 Output: 10000120 (start + offset)
703 Count: 00000018 (number of trace records)
704 CRC32: 9526fb66 (CRC32 of all trace records)
705
wdenkc6097192002-11-03 00:24:07 +0000706- Timestamp Support:
707
wdenk43d96162003-03-06 00:02:04 +0000708 When CONFIG_TIMESTAMP is selected, the timestamp
709 (date and time) of an image is printed by image
710 commands like bootm or iminfo. This option is
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500711 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000712
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000713- Partition Labels (disklabels) Supported:
714 Zero or more of the following:
715 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000716 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
717 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
718 bootloader. Note 2TB partition limit; see
719 disk/part_efi.c
Simon Glassc649e3c2016-05-01 11:36:02 -0600720 CONFIG_SCSI) you must configure support for at
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000721 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000722
723- IDE Reset method:
wdenk4d13cba2004-03-14 14:09:05 +0000724 CONFIG_IDE_RESET - is this is defined, IDE Reset will
725 be performed by calling the function
726 ide_set_reset(int reset)
727 which has to be defined in a board specific file
wdenkc6097192002-11-03 00:24:07 +0000728
729- ATAPI Support:
730 CONFIG_ATAPI
731
732 Set this to enable ATAPI support.
733
wdenkc40b2952004-03-13 23:29:43 +0000734- LBA48 Support
735 CONFIG_LBA48
736
737 Set this to enable support for disks larger than 137GB
Heiko Schocher4b142fe2009-12-03 11:21:21 +0100738 Also look at CONFIG_SYS_64BIT_LBA.
wdenkc40b2952004-03-13 23:29:43 +0000739 Whithout these , LBA48 support uses 32bit variables and will 'only'
740 support disks up to 2.1TB.
741
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200742 CONFIG_SYS_64BIT_LBA:
wdenkc40b2952004-03-13 23:29:43 +0000743 When enabled, makes the IDE subsystem use 64bit sector addresses.
744 Default is 32bit.
745
wdenkc6097192002-11-03 00:24:07 +0000746- SCSI Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200747 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
748 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
749 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
wdenkc6097192002-11-03 00:24:07 +0000750 maximum numbers of LUNs, SCSI ID's and target
751 devices.
wdenkc6097192002-11-03 00:24:07 +0000752
Wolfgang Denk93e14592013-10-04 17:43:24 +0200753 The environment variable 'scsidevs' is set to the number of
754 SCSI devices found during the last scan.
Stefan Reinauer447c0312012-10-29 05:23:48 +0000755
wdenkc6097192002-11-03 00:24:07 +0000756- NETWORK Support (PCI):
Kyle Moffettce5207e2011-10-18 11:05:29 +0000757 CONFIG_E1000_SPI
758 Utility code for direct access to the SPI bus on Intel 8257x.
759 This does not do anything useful unless you set at least one
760 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
761
wdenkc6097192002-11-03 00:24:07 +0000762 CONFIG_NATSEMI
763 Support for National dp83815 chips.
764
765 CONFIG_NS8382X
766 Support for National dp8382[01] gigabit chips.
767
wdenk45219c42003-05-12 21:50:16 +0000768- NETWORK Support (other):
Rob Herringefdd7312011-12-15 11:15:49 +0000769 CONFIG_CALXEDA_XGMAC
770 Support for the Calxeda XGMAC device
771
Ashok3bb46d22012-10-15 06:20:47 +0000772 CONFIG_LAN91C96
wdenk45219c42003-05-12 21:50:16 +0000773 Support for SMSC's LAN91C96 chips.
774
wdenk45219c42003-05-12 21:50:16 +0000775 CONFIG_LAN91C96_USE_32_BIT
776 Define this to enable 32 bit addressing
777
Ashok3bb46d22012-10-15 06:20:47 +0000778 CONFIG_SMC91111
wdenkf39748a2004-06-09 13:37:52 +0000779 Support for SMSC's LAN91C111 chip
780
781 CONFIG_SMC91111_BASE
782 Define this to hold the physical address
783 of the device (I/O space)
784
785 CONFIG_SMC_USE_32_BIT
786 Define this if data bus is 32 bits
787
788 CONFIG_SMC_USE_IOFUNCS
789 Define this to use i/o functions instead of macros
790 (some hardware wont work with macros)
791
Heiko Schocherdc02bad2011-11-15 10:00:04 -0500792 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
793 Define this if you have more then 3 PHYs.
794
Macpaul Linb3dbf4a52010-12-21 16:59:46 +0800795 CONFIG_FTGMAC100
796 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
797
798 CONFIG_FTGMAC100_EGIGA
799 Define this to use GE link update with gigabit PHY.
800 Define this if FTGMAC100 is connected to gigabit PHY.
801 If your system has 10/100 PHY only, it might not occur
802 wrong behavior. Because PHY usually return timeout or
803 useless data when polling gigabit status and gigabit
804 control registers. This behavior won't affect the
805 correctnessof 10/100 link speed update.
806
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +0900807 CONFIG_SH_ETHER
808 Support for Renesas on-chip Ethernet controller
809
810 CONFIG_SH_ETHER_USE_PORT
811 Define the number of ports to be used
812
813 CONFIG_SH_ETHER_PHY_ADDR
814 Define the ETH PHY's address
815
Yoshihiro Shimoda68260aa2011-01-27 10:06:08 +0900816 CONFIG_SH_ETHER_CACHE_WRITEBACK
817 If this option is set, the driver enables cache flush.
818
Vadim Bendebury5e124722011-10-17 08:36:14 +0000819- TPM Support:
Che-liang Chiou90899cc2013-04-12 11:04:34 +0000820 CONFIG_TPM
821 Support TPM devices.
822
Christophe Ricard0766ad22015-10-06 22:54:41 +0200823 CONFIG_TPM_TIS_INFINEON
824 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +0000825 per system is supported at this time.
826
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +0000827 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
828 Define the burst count bytes upper limit
829
Christophe Ricard3aa74082016-01-21 23:27:13 +0100830 CONFIG_TPM_ST33ZP24
831 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
832
833 CONFIG_TPM_ST33ZP24_I2C
834 Support for STMicroelectronics ST33ZP24 I2C devices.
835 Requires TPM_ST33ZP24 and I2C.
836
Christophe Ricardb75fdc12016-01-21 23:27:14 +0100837 CONFIG_TPM_ST33ZP24_SPI
838 Support for STMicroelectronics ST33ZP24 SPI devices.
839 Requires TPM_ST33ZP24 and SPI.
840
Dirk Eibachc01939c2013-06-26 15:55:15 +0200841 CONFIG_TPM_ATMEL_TWI
842 Support for Atmel TWI TPM device. Requires I2C support.
843
Che-liang Chiou90899cc2013-04-12 11:04:34 +0000844 CONFIG_TPM_TIS_LPC
Vadim Bendebury5e124722011-10-17 08:36:14 +0000845 Support for generic parallel port TPM devices. Only one device
846 per system is supported at this time.
847
848 CONFIG_TPM_TIS_BASE_ADDRESS
849 Base address where the generic TPM device is mapped
850 to. Contemporary x86 systems usually map it at
851 0xfed40000.
852
Reinhard Pfaube6c1522013-06-26 15:55:13 +0200853 CONFIG_TPM
854 Define this to enable the TPM support library which provides
855 functional interfaces to some TPM commands.
856 Requires support for a TPM device.
857
858 CONFIG_TPM_AUTH_SESSIONS
859 Define this to enable authorized functions in the TPM library.
860 Requires CONFIG_TPM and CONFIG_SHA1.
861
wdenkc6097192002-11-03 00:24:07 +0000862- USB Support:
863 At the moment only the UHCI host controller is
Heiko Schocher064b55c2017-06-14 05:49:40 +0200864 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +0000865 CONFIG_USB_UHCI to enable it.
866 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenk30d56fa2004-10-09 22:44:59 +0000867 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +0000868 storage devices.
869 Note:
870 Supported are USB Keyboards and USB Floppy drives
871 (TEAC FD-05PUB).
wdenk4d13cba2004-03-14 14:09:05 +0000872
Simon Glass9ab4ce22012-02-27 10:52:47 +0000873 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
874 txfilltuning field in the EHCI controller on reset.
875
Oleksandr Tymoshenko6e9e0622014-02-01 21:51:25 -0700876 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
877 HW module registers.
878
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200879- USB Device:
880 Define the below if you wish to use the USB console.
881 Once firmware is rebuilt from a serial console issue the
882 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200883 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200884 it has found a new device. The environment variable usbtty
885 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denk386eda02006-06-14 18:14:56 +0200886 appear to a USB host as a Linux gserial device or a
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200887 Common Device Class Abstract Control Model serial device.
888 If you select usbtty = gserial you should be able to enumerate
889 a Linux host by
890 # modprobe usbserial vendor=0xVendorID product=0xProductID
891 else if using cdc_acm, simply setting the environment
892 variable usbtty to be cdc_acm should suffice. The following
893 might be defined in YourBoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +0200894
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200895 CONFIG_USB_DEVICE
896 Define this to build a UDC device
wdenkc6097192002-11-03 00:24:07 +0000897
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200898 CONFIG_USB_TTY
899 Define this to have a tty type of device available to
900 talk to the UDC device
Wolfgang Denk386eda02006-06-14 18:14:56 +0200901
Vipin KUMARf9da0f82012-03-26 15:38:06 +0530902 CONFIG_USBD_HS
903 Define this to enable the high speed support for usb
904 device and usbtty. If this feature is enabled, a routine
905 int is_usbd_high_speed(void)
906 also needs to be defined by the driver to dynamically poll
907 whether the enumeration has succeded at high speed or full
908 speed.
909
Wolfgang Denk386eda02006-06-14 18:14:56 +0200910 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200911 define your own vendor specific values either in BoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +0200912 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200913 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
914 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
915 should pretend to be a Linux device to it's target host.
916
917 CONFIG_USBD_MANUFACTURER
918 Define this string as the name of your company for
919 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denk386eda02006-06-14 18:14:56 +0200920
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200921 CONFIG_USBD_PRODUCT_NAME
922 Define this string as the name of your product
923 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
924
925 CONFIG_USBD_VENDORID
926 Define this as your assigned Vendor ID from the USB
927 Implementors Forum. This *must* be a genuine Vendor ID
928 to avoid polluting the USB namespace.
929 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denk386eda02006-06-14 18:14:56 +0200930
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200931 CONFIG_USBD_PRODUCTID
932 Define this as the unique Product ID
933 for your device
934 - CONFIG_USBD_PRODUCTID 0xFFFF
wdenkc6097192002-11-03 00:24:07 +0000935
Igor Grinbergd70a5602011-12-12 12:08:35 +0200936- ULPI Layer Support:
937 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
938 the generic ULPI layer. The generic layer accesses the ULPI PHY
939 via the platform viewport, so you need both the genric layer and
940 the viewport enabled. Currently only Chipidea/ARC based
941 viewport is supported.
942 To enable the ULPI layer support, define CONFIG_USB_ULPI and
943 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stach6d365ea2012-10-01 00:44:35 +0200944 If your ULPI phy needs a different reference clock than the
945 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
946 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +0000947
948- MMC Support:
949 The MMC controller on the Intel PXA is supported. To
950 enable this define CONFIG_MMC. The MMC can be
951 accessed from the boot prompt by mapping the device
952 to physical memory similar to flash. Command line is
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500953 enabled with CONFIG_CMD_MMC. The MMC driver also works with
954 the FAT fs. This is enabled with CONFIG_CMD_FAT.
wdenkc6097192002-11-03 00:24:07 +0000955
Yoshihiro Shimodaafb35662011-07-04 22:21:22 +0000956 CONFIG_SH_MMCIF
957 Support for Renesas on-chip MMCIF controller
958
959 CONFIG_SH_MMCIF_ADDR
960 Define the base address of MMCIF registers
961
962 CONFIG_SH_MMCIF_CLK
963 Define the clock frequency for MMCIF
964
Tom Rinib3ba6e92013-03-14 05:32:47 +0000965- USB Device Firmware Update (DFU) class support:
Marek Vasutbb4059a2018-02-16 16:41:18 +0100966 CONFIG_DFU_OVER_USB
Tom Rinib3ba6e92013-03-14 05:32:47 +0000967 This enables the USB portion of the DFU USB class
968
Pantelis Antoniouc6631762013-03-14 05:32:52 +0000969 CONFIG_DFU_NAND
970 This enables support for exposing NAND devices via DFU.
971
Afzal Mohammeda9479f02013-09-18 01:15:24 +0530972 CONFIG_DFU_RAM
973 This enables support for exposing RAM via DFU.
974 Note: DFU spec refer to non-volatile memory usage, but
975 allow usages beyond the scope of spec - here RAM usage,
976 one that would help mostly the developer.
977
Heiko Schochere7e75c72013-06-12 06:05:51 +0200978 CONFIG_SYS_DFU_DATA_BUF_SIZE
979 Dfu transfer uses a buffer before writing data to the
980 raw storage device. Make the size (in bytes) of this buffer
981 configurable. The size of this buffer is also configurable
982 through the "dfu_bufsiz" environment variable.
983
Pantelis Antoniouea2453d2013-03-14 05:32:48 +0000984 CONFIG_SYS_DFU_MAX_FILE_SIZE
985 When updating files rather than the raw storage device,
986 we use a static buffer to copy the file into and then write
987 the buffer once we've been given the whole file. Define
988 this to the maximum filesize (in bytes) for the buffer.
989 Default is 4 MiB if undefined.
990
Heiko Schocher001a8312014-03-18 08:09:56 +0100991 DFU_DEFAULT_POLL_TIMEOUT
992 Poll timeout [ms], is the timeout a device can send to the
993 host. The host must wait for this timeout before sending
994 a subsequent DFU_GET_STATUS request to the device.
995
996 DFU_MANIFEST_POLL_TIMEOUT
997 Poll timeout [ms], which the device sends to the host when
998 entering dfuMANIFEST state. Host waits this timeout, before
999 sending again an USB request to the device.
1000
wdenk6705d812004-08-02 23:22:59 +00001001- Journaling Flash filesystem support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001002 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1003 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenk6705d812004-08-02 23:22:59 +00001004 Define these for a default partition on a NOR device
1005
wdenkc6097192002-11-03 00:24:07 +00001006- Keyboard Support:
Simon Glass39f615e2015-11-11 10:05:47 -07001007 See Kconfig help for available keyboard drivers.
1008
wdenkc6097192002-11-03 00:24:07 +00001009- Video support:
Timur Tabi7d3053f2011-02-15 17:09:19 -06001010 CONFIG_FSL_DIU_FB
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001011 Enable the Freescale DIU video driver. Reference boards for
Timur Tabi7d3053f2011-02-15 17:09:19 -06001012 SOCs that have a DIU should define this macro to enable DIU
1013 support, and should also define these other macros:
1014
1015 CONFIG_SYS_DIU_ADDR
1016 CONFIG_VIDEO
Timur Tabi7d3053f2011-02-15 17:09:19 -06001017 CONFIG_CFB_CONSOLE
1018 CONFIG_VIDEO_SW_CURSOR
1019 CONFIG_VGA_AS_SINGLE_DEVICE
Timur Tabi7d3053f2011-02-15 17:09:19 -06001020 CONFIG_VIDEO_BMP_LOGO
1021
Timur Tabiba8e76b2011-04-11 14:18:22 -05001022 The DIU driver will look for the 'video-mode' environment
1023 variable, and if defined, enable the DIU as a console during
Fabio Estevam8eca9432016-04-02 11:53:18 -03001024 boot. See the documentation file doc/README.video for a
Timur Tabiba8e76b2011-04-11 14:18:22 -05001025 description of this variable.
Timur Tabi7d3053f2011-02-15 17:09:19 -06001026
wdenkc6097192002-11-03 00:24:07 +00001027- LCD Support: CONFIG_LCD
1028
1029 Define this to enable LCD support (for output to LCD
1030 display); also select one of the supported displays
1031 by defining one of these:
1032
Stelian Pop39cf4802008-05-09 21:57:18 +02001033 CONFIG_ATMEL_LCD:
1034
1035 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1036
wdenkfd3103b2003-11-25 16:55:19 +00001037 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +00001038
wdenkfd3103b2003-11-25 16:55:19 +00001039 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +00001040
wdenkfd3103b2003-11-25 16:55:19 +00001041 CONFIG_NEC_NL6448BC20
wdenkc6097192002-11-03 00:24:07 +00001042
wdenkfd3103b2003-11-25 16:55:19 +00001043 NEC NL6448BC20-08. 6.5", 640x480.
1044 Active, color, single scan.
1045
1046 CONFIG_NEC_NL6448BC33_54
1047
1048 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +00001049 Active, color, single scan.
1050
1051 CONFIG_SHARP_16x9
1052
1053 Sharp 320x240. Active, color, single scan.
1054 It isn't 16x9, and I am not sure what it is.
1055
1056 CONFIG_SHARP_LQ64D341
1057
1058 Sharp LQ64D341 display, 640x480.
1059 Active, color, single scan.
1060
1061 CONFIG_HLD1045
1062
1063 HLD1045 display, 640x480.
1064 Active, color, single scan.
1065
1066 CONFIG_OPTREX_BW
1067
1068 Optrex CBL50840-2 NF-FW 99 22 M5
1069 or
1070 Hitachi LMG6912RPFC-00T
1071 or
1072 Hitachi SP14Q002
1073
1074 320x240. Black & white.
1075
Simon Glass676d3192012-10-17 13:24:54 +00001076 CONFIG_LCD_ALIGNMENT
1077
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001078 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass676d3192012-10-17 13:24:54 +00001079 defined then the LCD will be aligned to this value instead.
1080 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1081 here, since it is cheaper to change data cache settings on
1082 a per-section basis.
1083
1084
Hannes Petermaier604c7d42015-03-27 08:01:38 +01001085 CONFIG_LCD_ROTATION
1086
1087 Sometimes, for example if the display is mounted in portrait
1088 mode or even if it's mounted landscape but rotated by 180degree,
1089 we need to rotate our content of the display relative to the
1090 framebuffer, so that user can read the messages which are
1091 printed out.
1092 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1093 initialized with a given rotation from "vl_rot" out of
1094 "vidinfo_t" which is provided by the board specific code.
1095 The value for vl_rot is coded as following (matching to
1096 fbcon=rotate:<n> linux-kernel commandline):
1097 0 = no rotation respectively 0 degree
1098 1 = 90 degree rotation
1099 2 = 180 degree rotation
1100 3 = 270 degree rotation
1101
1102 If CONFIG_LCD_ROTATION is not defined, the console will be
1103 initialized with 0degree rotation.
1104
Tom Wai-Hong Tam45d7f522012-09-28 15:11:16 +00001105 CONFIG_LCD_BMP_RLE8
1106
1107 Support drawing of RLE8-compressed bitmaps on the LCD.
1108
wdenk17ea1172004-06-06 21:51:03 +00001109- MII/PHY support:
wdenk17ea1172004-06-06 21:51:03 +00001110 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1111
1112 The clock frequency of the MII bus
1113
wdenk17ea1172004-06-06 21:51:03 +00001114 CONFIG_PHY_RESET_DELAY
1115
1116 Some PHY like Intel LXT971A need extra delay after
1117 reset before any MII register access is possible.
1118 For such PHY, set this option to the usec delay
1119 required. (minimum 300usec for LXT971A)
1120
1121 CONFIG_PHY_CMD_DELAY (ppc4xx)
1122
1123 Some PHY like Intel LXT971A need extra delay after
1124 command issued before MII status register can be read
1125
wdenkc6097192002-11-03 00:24:07 +00001126- IP address:
1127 CONFIG_IPADDR
1128
1129 Define a default value for the IP address to use for
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001130 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +00001131 determined through e.g. bootp.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001132 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +00001133
1134- Server IP address:
1135 CONFIG_SERVERIP
1136
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001137 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +00001138 server to contact when using the "tftboot" command.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001139 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +00001140
Robin Getz97cfe862009-07-21 12:15:28 -04001141 CONFIG_KEEP_SERVERADDR
1142
1143 Keeps the server's MAC address, in the env 'serveraddr'
1144 for passing to bootargs (like Linux's netconsole option)
1145
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001146- Gateway IP address:
1147 CONFIG_GATEWAYIP
1148
1149 Defines a default value for the IP address of the
1150 default router where packets to other networks are
1151 sent to.
1152 (Environment variable "gatewayip")
1153
1154- Subnet mask:
1155 CONFIG_NETMASK
1156
1157 Defines a default value for the subnet mask (or
1158 routing prefix) which is used to determine if an IP
1159 address belongs to the local subnet or needs to be
1160 forwarded through a router.
1161 (Environment variable "netmask")
1162
wdenkc6097192002-11-03 00:24:07 +00001163- BOOTP Recovery Mode:
1164 CONFIG_BOOTP_RANDOM_DELAY
1165
1166 If you have many targets in a network that try to
1167 boot using BOOTP, you may want to avoid that all
1168 systems send out BOOTP requests at precisely the same
1169 moment (which would happen for instance at recovery
1170 from a power failure, when all systems will try to
1171 boot, thus flooding the BOOTP server. Defining
1172 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1173 inserted before sending out BOOTP requests. The
Wolfgang Denk6c33c782007-08-06 23:21:05 +02001174 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +00001175
1176 1st BOOTP request: delay 0 ... 1 sec
1177 2nd BOOTP request: delay 0 ... 2 sec
1178 3rd BOOTP request: delay 0 ... 4 sec
1179 4th and following
1180 BOOTP requests: delay 0 ... 8 sec
1181
Thierry Reding92ac8ac2014-08-19 10:21:24 +02001182 CONFIG_BOOTP_ID_CACHE_SIZE
1183
1184 BOOTP packets are uniquely identified using a 32-bit ID. The
1185 server will copy the ID from client requests to responses and
1186 U-Boot will use this to determine if it is the destination of
1187 an incoming response. Some servers will check that addresses
1188 aren't in use before handing them out (usually using an ARP
1189 ping) and therefore take up to a few hundred milliseconds to
1190 respond. Network congestion may also influence the time it
1191 takes for a response to make it back to the client. If that
1192 time is too long, U-Boot will retransmit requests. In order
1193 to allow earlier responses to still be accepted after these
1194 retransmissions, U-Boot's BOOTP client keeps a small cache of
1195 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1196 cache. The default is to keep IDs for up to four outstanding
1197 requests. Increasing this will allow U-Boot to accept offers
1198 from a BOOTP client in networks with unusually high latency.
1199
stroesefe389a82003-08-28 14:17:32 +00001200- DHCP Advanced Options:
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001201 You can fine tune the DHCP functionality by defining
1202 CONFIG_BOOTP_* symbols:
stroesefe389a82003-08-28 14:17:32 +00001203
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001204 CONFIG_BOOTP_NISDOMAIN
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001205 CONFIG_BOOTP_BOOTFILESIZE
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001206 CONFIG_BOOTP_NTPSERVER
1207 CONFIG_BOOTP_TIMEOFFSET
1208 CONFIG_BOOTP_VENDOREX
Joe Hershberger2c00e092012-05-23 07:59:19 +00001209 CONFIG_BOOTP_MAY_FAIL
stroesefe389a82003-08-28 14:17:32 +00001210
Wilson Callan5d110f02007-07-28 10:56:13 -04001211 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1212 environment variable, not the BOOTP server.
stroesefe389a82003-08-28 14:17:32 +00001213
Joe Hershberger2c00e092012-05-23 07:59:19 +00001214 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1215 after the configured retry count, the call will fail
1216 instead of starting over. This can be used to fail over
1217 to Link-local IP address configuration if the DHCP server
1218 is not available.
1219
Aras Vaichasd9a2f412008-03-26 09:43:57 +11001220 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1221
1222 A 32bit value in microseconds for a delay between
1223 receiving a "DHCP Offer" and sending the "DHCP Request".
1224 This fixes a problem with certain DHCP servers that don't
1225 respond 100% of the time to a "DHCP request". E.g. On an
1226 AT91RM9200 processor running at 180MHz, this delay needed
1227 to be *at least* 15,000 usec before a Windows Server 2003
1228 DHCP server would reply 100% of the time. I recommend at
1229 least 50,000 usec to be safe. The alternative is to hope
1230 that one of the retries will be successful but note that
1231 the DHCP timeout and retry process takes a longer than
1232 this delay.
1233
Joe Hershbergerd22c3382012-05-23 08:00:12 +00001234 - Link-local IP address negotiation:
1235 Negotiate with other link-local clients on the local network
1236 for an address that doesn't require explicit configuration.
1237 This is especially useful if a DHCP server cannot be guaranteed
1238 to exist in all environments that the device must operate.
1239
1240 See doc/README.link-local for more information.
1241
Prabhakar Kushwaha24acb832017-11-23 16:51:32 +05301242 - MAC address from environment variables
1243
1244 FDT_SEQ_MACADDR_FROM_ENV
1245
1246 Fix-up device tree with MAC addresses fetched sequentially from
1247 environment variables. This config work on assumption that
1248 non-usable ethernet node of device-tree are either not present
1249 or their status has been marked as "disabled".
1250
wdenka3d991b2004-04-15 21:48:45 +00001251 - CDP Options:
wdenk6e592382004-04-18 17:39:38 +00001252 CONFIG_CDP_DEVICE_ID
wdenka3d991b2004-04-15 21:48:45 +00001253
1254 The device id used in CDP trigger frames.
1255
1256 CONFIG_CDP_DEVICE_ID_PREFIX
1257
1258 A two character string which is prefixed to the MAC address
1259 of the device.
1260
1261 CONFIG_CDP_PORT_ID
1262
1263 A printf format string which contains the ascii name of
1264 the port. Normally is set to "eth%d" which sets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001265 eth0 for the first Ethernet, eth1 for the second etc.
wdenka3d991b2004-04-15 21:48:45 +00001266
1267 CONFIG_CDP_CAPABILITIES
1268
1269 A 32bit integer which indicates the device capabilities;
1270 0x00000010 for a normal host which does not forwards.
1271
1272 CONFIG_CDP_VERSION
1273
1274 An ascii string containing the version of the software.
1275
1276 CONFIG_CDP_PLATFORM
1277
1278 An ascii string containing the name of the platform.
1279
1280 CONFIG_CDP_TRIGGER
1281
1282 A 32bit integer sent on the trigger.
1283
1284 CONFIG_CDP_POWER_CONSUMPTION
1285
1286 A 16bit integer containing the power consumption of the
1287 device in .1 of milliwatts.
1288
1289 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1290
1291 A byte containing the id of the VLAN.
1292
Uri Mashiach79267ed2017-01-19 10:51:05 +02001293- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +00001294
1295 Several configurations allow to display the current
1296 status using a LED. For instance, the LED will blink
1297 fast while running U-Boot code, stop blinking as
1298 soon as a reply to a BOOTP request was received, and
1299 start blinking slow once the Linux kernel is running
1300 (supported by a status LED driver in the Linux
Uri Mashiach79267ed2017-01-19 10:51:05 +02001301 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +00001302 feature in U-Boot.
1303
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001304 Additional options:
1305
Uri Mashiach79267ed2017-01-19 10:51:05 +02001306 CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001307 The status LED can be connected to a GPIO pin.
1308 In such cases, the gpio_led driver can be used as a
Uri Mashiach79267ed2017-01-19 10:51:05 +02001309 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001310 to include the gpio_led driver in the U-Boot binary.
1311
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +02001312 CONFIG_GPIO_LED_INVERTED_TABLE
1313 Some GPIO connected LEDs may have inverted polarity in which
1314 case the GPIO high value corresponds to LED off state and
1315 GPIO low value corresponds to LED on state.
1316 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1317 with a list of GPIO LEDs that have inverted polarity.
1318
Tom Rini55dabcc2021-08-18 23:12:24 -04001319- I2C Support:
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001320 CONFIG_SYS_NUM_I2C_BUSES
Simon Glass945a18e2016-10-02 18:01:05 -06001321 Hold the number of i2c buses you want to use.
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001322
1323 CONFIG_SYS_I2C_DIRECT_BUS
1324 define this, if you don't use i2c muxes on your hardware.
1325 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1326 omit this define.
1327
1328 CONFIG_SYS_I2C_MAX_HOPS
1329 define how many muxes are maximal consecutively connected
1330 on one i2c bus. If you not use i2c muxes, omit this
1331 define.
1332
1333 CONFIG_SYS_I2C_BUSES
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001334 hold a list of buses you want to use, only used if
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001335 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1336 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1337 CONFIG_SYS_NUM_I2C_BUSES = 9:
1338
1339 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1340 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1341 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1342 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1343 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1344 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1345 {1, {I2C_NULL_HOP}}, \
1346 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1347 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1348 }
1349
1350 which defines
1351 bus 0 on adapter 0 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001352 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1353 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1354 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1355 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1356 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001357 bus 6 on adapter 1 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001358 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1359 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001360
1361 If you do not have i2c muxes on your board, omit this define.
1362
Simon Glassce3b5d62017-05-12 21:10:00 -06001363- Legacy I2C Support:
Heiko Schocherea818db2013-01-29 08:53:15 +01001364 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb37c7e52003-06-30 16:24:52 +00001365 then the following macros need to be defined (examples are
1366 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001367
1368 I2C_INIT
1369
wdenkb37c7e52003-06-30 16:24:52 +00001370 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +00001371 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001372
wdenkba56f622004-02-06 23:19:44 +00001373 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb37c7e52003-06-30 16:24:52 +00001374
wdenkc6097192002-11-03 00:24:07 +00001375 I2C_ACTIVE
1376
1377 The code necessary to make the I2C data line active
1378 (driven). If the data line is open collector, this
1379 define can be null.
1380
wdenkb37c7e52003-06-30 16:24:52 +00001381 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1382
wdenkc6097192002-11-03 00:24:07 +00001383 I2C_TRISTATE
1384
1385 The code necessary to make the I2C data line tri-stated
1386 (inactive). If the data line is open collector, this
1387 define can be null.
1388
wdenkb37c7e52003-06-30 16:24:52 +00001389 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1390
wdenkc6097192002-11-03 00:24:07 +00001391 I2C_READ
1392
York Sun472d5462013-04-01 11:29:11 -07001393 Code that returns true if the I2C data line is high,
1394 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001395
wdenkb37c7e52003-06-30 16:24:52 +00001396 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1397
wdenkc6097192002-11-03 00:24:07 +00001398 I2C_SDA(bit)
1399
York Sun472d5462013-04-01 11:29:11 -07001400 If <bit> is true, sets the I2C data line high. If it
1401 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001402
wdenkb37c7e52003-06-30 16:24:52 +00001403 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +00001404 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenkba56f622004-02-06 23:19:44 +00001405 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +00001406
wdenkc6097192002-11-03 00:24:07 +00001407 I2C_SCL(bit)
1408
York Sun472d5462013-04-01 11:29:11 -07001409 If <bit> is true, sets the I2C clock line high. If it
1410 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001411
wdenkb37c7e52003-06-30 16:24:52 +00001412 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +00001413 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenkba56f622004-02-06 23:19:44 +00001414 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +00001415
wdenkc6097192002-11-03 00:24:07 +00001416 I2C_DELAY
1417
1418 This delay is invoked four times per clock cycle so this
1419 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +00001420 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +00001421 like:
1422
wdenkb37c7e52003-06-30 16:24:52 +00001423 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001424
Mike Frysinger793b5722010-07-21 13:38:02 -04001425 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1426
1427 If your arch supports the generic GPIO framework (asm/gpio.h),
1428 then you may alternatively define the two GPIOs that are to be
1429 used as SCL / SDA. Any of the previous I2C_xxx macros will
1430 have GPIO-based defaults assigned to them as appropriate.
1431
1432 You should define these to the GPIO value as given directly to
1433 the generic GPIO functions.
1434
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001435 CONFIG_SYS_I2C_INIT_BOARD
wdenk47cd00f2003-03-06 13:39:27 +00001436
wdenk8bde7f72003-06-27 21:31:46 +00001437 When a board is reset during an i2c bus transfer
1438 chips might think that the current transfer is still
1439 in progress. On some boards it is possible to access
1440 the i2c SCLK line directly, either by using the
1441 processor pin as a GPIO or by having a second pin
1442 connected to the bus. If this option is defined a
1443 custom i2c_init_board() routine in boards/xxx/board.c
1444 is run early in the boot sequence.
wdenk47cd00f2003-03-06 13:39:27 +00001445
Ben Warrenbb99ad62006-09-07 16:50:54 -04001446 CONFIG_I2C_MULTI_BUS
1447
1448 This option allows the use of multiple I2C buses, each of which
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001449 must have a controller. At any point in time, only one bus is
1450 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001451 Note that bus numbering is zero-based.
1452
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001453 CONFIG_SYS_I2C_NOPROBES
Ben Warrenbb99ad62006-09-07 16:50:54 -04001454
1455 This option specifies a list of I2C devices that will be skipped
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001456 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser0f89c542009-04-18 22:34:03 -05001457 is set, specify a list of bus-device pairs. Otherwise, specify
1458 a 1D array of device addresses
Ben Warrenbb99ad62006-09-07 16:50:54 -04001459
1460 e.g.
1461 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001462 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001463
1464 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1465
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001466 #define CONFIG_I2C_MULTI_BUS
Simon Glass945a18e2016-10-02 18:01:05 -06001467 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001468
1469 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1470
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001471 CONFIG_SYS_SPD_BUS_NUM
Timur Tabibe5e6182006-11-03 19:15:00 -06001472
1473 If defined, then this indicates the I2C bus number for DDR SPD.
1474 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1475
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001476 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese0dc018e2007-02-20 10:51:26 +01001477
1478 If defined, then this indicates the I2C bus number for the RTC.
1479 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1480
Andrew Dyer2ac69852008-12-29 17:36:01 -06001481 CONFIG_SOFT_I2C_READ_REPEATED_START
1482
1483 defining this will force the i2c_read() function in
1484 the soft_i2c driver to perform an I2C repeated start
1485 between writing the address pointer and reading the
1486 data. If this define is omitted the default behaviour
1487 of doing a stop-start sequence will be used. Most I2C
1488 devices can use either method, but some require one or
1489 the other.
Timur Tabibe5e6182006-11-03 19:15:00 -06001490
wdenkc6097192002-11-03 00:24:07 +00001491- SPI Support: CONFIG_SPI
1492
1493 Enables SPI driver (so far only tested with
1494 SPI EEPROM, also an instance works with Crystal A/D and
1495 D/As on the SACSng board)
1496
Heiko Schocherf659b572014-07-14 10:22:11 +02001497 CONFIG_SYS_SPI_MXC_WAIT
1498 Timeout for waiting until spi transfer completed.
1499 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1500
Matthias Fuchs01335022007-12-27 17:12:34 +01001501- FPGA Support: CONFIG_FPGA
1502
1503 Enables FPGA subsystem.
1504
1505 CONFIG_FPGA_<vendor>
1506
1507 Enables support for specific chip vendors.
1508 (ALTERA, XILINX)
1509
1510 CONFIG_FPGA_<family>
1511
1512 Enables support for FPGA family.
1513 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1514
1515 CONFIG_FPGA_COUNT
wdenkc6097192002-11-03 00:24:07 +00001516
wdenk43d96162003-03-06 00:02:04 +00001517 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00001518
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001519 CONFIG_SYS_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00001520
wdenk8bde7f72003-06-27 21:31:46 +00001521 Enable printing of hash marks during FPGA configuration.
wdenkc6097192002-11-03 00:24:07 +00001522
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001523 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00001524
wdenk43d96162003-03-06 00:02:04 +00001525 Enable checks on FPGA configuration interface busy
1526 status by the configuration function. This option
1527 will require a board or device specific function to
1528 be written.
wdenkc6097192002-11-03 00:24:07 +00001529
1530 CONFIG_FPGA_DELAY
1531
1532 If defined, a function that provides delays in the FPGA
1533 configuration driver.
1534
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001535 CONFIG_SYS_FPGA_CHECK_CTRLC
wdenkc6097192002-11-03 00:24:07 +00001536 Allow Control-C to interrupt FPGA configuration
1537
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001538 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00001539
wdenk43d96162003-03-06 00:02:04 +00001540 Check for configuration errors during FPGA bitfile
1541 loading. For example, abort during Virtex II
1542 configuration if the INIT_B line goes low (which
1543 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00001544
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001545 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00001546
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001547 Maximum time to wait for the INIT_B line to de-assert
1548 after PROB_B has been de-asserted during a Virtex II
wdenk43d96162003-03-06 00:02:04 +00001549 FPGA configuration sequence. The default time is 500
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001550 ms.
wdenkc6097192002-11-03 00:24:07 +00001551
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001552 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00001553
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001554 Maximum time to wait for BUSY to de-assert during
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001555 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00001556
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001557 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00001558
wdenk43d96162003-03-06 00:02:04 +00001559 Time to wait after FPGA configuration. The default is
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001560 200 ms.
wdenkc6097192002-11-03 00:24:07 +00001561
wdenkc6097192002-11-03 00:24:07 +00001562- Vendor Parameter Protection:
1563
wdenk43d96162003-03-06 00:02:04 +00001564 U-Boot considers the values of the environment
1565 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +00001566 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +00001567 are set once by the board vendor / manufacturer, and
1568 protects these variables from casual modification by
1569 the user. Once set, these variables are read-only,
1570 and write or delete attempts are rejected. You can
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001571 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00001572
1573 If CONFIG_ENV_OVERWRITE is #defined in your config
1574 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +00001575 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00001576 these parameters.
1577
Joe Hershberger92ac5202015-05-04 14:55:14 -05001578 Alternatively, if you define _both_ an ethaddr in the
1579 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001580 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00001581 which can be changed exactly ONCE by the user. [The
1582 serial# is unaffected by this, i. e. it remains
1583 read-only.]
1584
Joe Hershberger25980902012-12-11 22:16:31 -06001585 The same can be accomplished in a more flexible way
1586 for any variable by configuring the type of access
1587 to allow for those variables in the ".flags" variable
1588 or define CONFIG_ENV_FLAGS_LIST_STATIC.
1589
wdenkc6097192002-11-03 00:24:07 +00001590- Protected RAM:
1591 CONFIG_PRAM
1592
1593 Define this variable to enable the reservation of
1594 "protected RAM", i. e. RAM which is not overwritten
1595 by U-Boot. Define CONFIG_PRAM to hold the number of
1596 kB you want to reserve for pRAM. You can overwrite
1597 this default value by defining an environment
1598 variable "pram" to the number of kB you want to
1599 reserve. Note that the board info structure will
1600 still show the full amount of RAM. If pRAM is
1601 reserved, a new environment variable "mem" will
1602 automatically be defined to hold the amount of
1603 remaining RAM in a form that can be passed as boot
1604 argument to Linux, for instance like that:
1605
Wolfgang Denkfe126d82005-11-20 21:40:11 +01001606 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00001607 saveenv
1608
1609 This way you can tell Linux not to use this memory,
1610 either, which results in a memory region that will
1611 not be affected by reboots.
1612
1613 *WARNING* If your board configuration uses automatic
1614 detection of the RAM size, you must make sure that
1615 this memory test is non-destructive. So far, the
1616 following board configurations are known to be
1617 "pRAM-clean":
1618
Heiko Schocher5b8e76c2017-06-07 17:33:09 +02001619 IVMS8, IVML24, SPD8xx,
Wolfgang Denk1b0757e2012-10-24 02:36:15 +00001620 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02001621 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00001622
1623- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00001624 CONFIG_NET_RETRY_COUNT
1625
wdenk43d96162003-03-06 00:02:04 +00001626 This variable defines the number of retries for
1627 network operations like ARP, RARP, TFTP, or BOOTP
1628 before giving up the operation. If not defined, a
1629 default value of 5 is used.
wdenkc6097192002-11-03 00:24:07 +00001630
Guennadi Liakhovetski40cb90e2008-04-03 17:04:19 +02001631 CONFIG_ARP_TIMEOUT
1632
1633 Timeout waiting for an ARP reply in milliseconds.
1634
Tetsuyuki Kobayashi48a3e992012-07-03 22:25:21 +00001635 CONFIG_NFS_TIMEOUT
1636
1637 Timeout in milliseconds used in NFS protocol.
1638 If you encounter "ERROR: Cannot umount" in nfs command,
1639 try longer timeout such as
1640 #define CONFIG_NFS_TIMEOUT 10000UL
1641
wdenkc6097192002-11-03 00:24:07 +00001642 Note:
1643
wdenk8bde7f72003-06-27 21:31:46 +00001644 In the current implementation, the local variables
1645 space and global environment variables space are
1646 separated. Local variables are those you define by
1647 simply typing `name=value'. To access a local
1648 variable later on, you have write `$name' or
1649 `${name}'; to execute the contents of a variable
1650 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00001651
wdenk43d96162003-03-06 00:02:04 +00001652 Global environment variables are those you use
1653 setenv/printenv to work with. To run a command stored
1654 in such a variable, you need to use the run command,
1655 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00001656
1657 To store commands and special characters in a
1658 variable, please use double quotation marks
1659 surrounding the whole text of the variable, instead
1660 of the backslashes before semicolons and special
1661 symbols.
1662
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001663- Command Line Editing and History:
Marek Vasutf3b267b2016-01-27 04:47:55 +01001664 CONFIG_CMDLINE_PS_SUPPORT
1665
1666 Enable support for changing the command prompt string
1667 at run-time. Only static string is supported so far.
1668 The string is obtained from environment variables PS1
1669 and PS2.
1670
wdenka8c7c702003-12-06 19:49:23 +00001671- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00001672 CONFIG_EXTRA_ENV_SETTINGS
1673
wdenk43d96162003-03-06 00:02:04 +00001674 Define this to contain any number of null terminated
1675 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00001676 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00001677
wdenk43d96162003-03-06 00:02:04 +00001678 For example, place something like this in your
1679 board's config file:
wdenkc6097192002-11-03 00:24:07 +00001680
1681 #define CONFIG_EXTRA_ENV_SETTINGS \
1682 "myvar1=value1\0" \
1683 "myvar2=value2\0"
1684
wdenk43d96162003-03-06 00:02:04 +00001685 Warning: This method is based on knowledge about the
1686 internal format how the environment is stored by the
1687 U-Boot code. This is NOT an official, exported
1688 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00001689 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00001690 You better know what you are doing here.
1691
wdenk43d96162003-03-06 00:02:04 +00001692 Note: overly (ab)use of the default environment is
1693 discouraged. Make sure to check other ways to preset
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02001694 the environment like the "source" command or the
wdenk43d96162003-03-06 00:02:04 +00001695 boot command first.
wdenkc6097192002-11-03 00:24:07 +00001696
Simon Glass06fd8532012-11-30 13:01:17 +00001697 CONFIG_DELAY_ENVIRONMENT
1698
1699 Normally the environment is loaded when the board is
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001700 initialised so that it is available to U-Boot. This inhibits
Simon Glass06fd8532012-11-30 13:01:17 +00001701 that so that the environment is not available until
1702 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
1703 this is instead controlled by the value of
1704 /config/load-environment.
1705
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02001706- TFTP Fixed UDP Port:
1707 CONFIG_TFTP_PORT
1708
Wolfgang Denk28cb9372005-09-24 23:25:46 +02001709 If this is defined, the environment variable tftpsrcp
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02001710 is used to supply the TFTP UDP source port value.
Wolfgang Denk28cb9372005-09-24 23:25:46 +02001711 If tftpsrcp isn't defined, the normal pseudo-random port
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02001712 number generator is used.
1713
Wolfgang Denk28cb9372005-09-24 23:25:46 +02001714 Also, the environment variable tftpdstp is used to supply
1715 the TFTP UDP destination port value. If tftpdstp isn't
1716 defined, the normal port 69 is used.
1717
1718 The purpose for tftpsrcp is to allow a TFTP server to
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02001719 blindly start the TFTP transfer using the pre-configured
1720 target IP address and UDP port. This has the effect of
1721 "punching through" the (Windows XP) firewall, allowing
1722 the remainder of the TFTP transfer to proceed normally.
1723 A better solution is to properly configure the firewall,
1724 but sometimes that is not allowed.
1725
Wolfgang Denk4cf26092011-10-07 09:58:21 +02001726 CONFIG_STANDALONE_LOAD_ADDR
1727
Wolfgang Denk6feff892011-10-09 21:06:34 +02001728 This option defines a board specific value for the
1729 address where standalone program gets loaded, thus
1730 overwriting the architecture dependent default
Wolfgang Denk4cf26092011-10-07 09:58:21 +02001731 settings.
1732
1733- Frame Buffer Address:
1734 CONFIG_FB_ADDR
1735
1736 Define CONFIG_FB_ADDR if you want to use specific
Wolfgang Denk44a53b52013-01-03 00:43:59 +00001737 address for frame buffer. This is typically the case
1738 when using a graphics controller has separate video
1739 memory. U-Boot will then place the frame buffer at
1740 the given address instead of dynamically reserving it
1741 in system RAM by calling lcd_setmem(), which grabs
1742 the memory for the frame buffer depending on the
1743 configured panel size.
Wolfgang Denk4cf26092011-10-07 09:58:21 +02001744
1745 Please see board_init_f function.
1746
Detlev Zundelcccfc2a2009-12-01 17:16:19 +01001747- Automatic software updates via TFTP server
1748 CONFIG_UPDATE_TFTP
1749 CONFIG_UPDATE_TFTP_CNT_MAX
1750 CONFIG_UPDATE_TFTP_MSEC_MAX
1751
1752 These options enable and control the auto-update feature;
1753 for a more detailed description refer to doc/README.update.
1754
1755- MTD Support (mtdparts command, UBI support)
Heiko Schocherff94bc42014-06-24 10:10:04 +02001756 CONFIG_MTD_UBI_WL_THRESHOLD
1757 This parameter defines the maximum difference between the highest
1758 erase counter value and the lowest erase counter value of eraseblocks
1759 of UBI devices. When this threshold is exceeded, UBI starts performing
1760 wear leveling by means of moving data from eraseblock with low erase
1761 counter to eraseblocks with high erase counter.
1762
1763 The default value should be OK for SLC NAND flashes, NOR flashes and
1764 other flashes which have eraseblock life-cycle 100000 or more.
1765 However, in case of MLC NAND flashes which typically have eraseblock
1766 life-cycle less than 10000, the threshold should be lessened (e.g.,
1767 to 128 or 256, although it does not have to be power of 2).
1768
1769 default: 4096
Simon Glassc654b512014-10-23 18:58:54 -06001770
Heiko Schocherff94bc42014-06-24 10:10:04 +02001771 CONFIG_MTD_UBI_BEB_LIMIT
1772 This option specifies the maximum bad physical eraseblocks UBI
1773 expects on the MTD device (per 1024 eraseblocks). If the
1774 underlying flash does not admit of bad eraseblocks (e.g. NOR
1775 flash), this value is ignored.
1776
1777 NAND datasheets often specify the minimum and maximum NVM
1778 (Number of Valid Blocks) for the flashes' endurance lifetime.
1779 The maximum expected bad eraseblocks per 1024 eraseblocks
1780 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
1781 which gives 20 for most NANDs (MaxNVB is basically the total
1782 count of eraseblocks on the chip).
1783
1784 To put it differently, if this value is 20, UBI will try to
1785 reserve about 1.9% of physical eraseblocks for bad blocks
1786 handling. And that will be 1.9% of eraseblocks on the entire
1787 NAND chip, not just the MTD partition UBI attaches. This means
1788 that if you have, say, a NAND flash chip admits maximum 40 bad
1789 eraseblocks, and it is split on two MTD partitions of the same
1790 size, UBI will reserve 40 eraseblocks when attaching a
1791 partition.
1792
1793 default: 20
1794
1795 CONFIG_MTD_UBI_FASTMAP
1796 Fastmap is a mechanism which allows attaching an UBI device
1797 in nearly constant time. Instead of scanning the whole MTD device it
1798 only has to locate a checkpoint (called fastmap) on the device.
1799 The on-flash fastmap contains all information needed to attach
1800 the device. Using fastmap makes only sense on large devices where
1801 attaching by scanning takes long. UBI will not automatically install
1802 a fastmap on old images, but you can set the UBI parameter
1803 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
1804 that fastmap-enabled images are still usable with UBI implementations
1805 without fastmap support. On typical flash devices the whole fastmap
1806 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
1807
1808 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
1809 Set this parameter to enable fastmap automatically on images
1810 without a fastmap.
1811 default: 0
1812
Heiko Schocher0195a7b2015-10-22 06:19:21 +02001813 CONFIG_MTD_UBI_FM_DEBUG
1814 Enable UBI fastmap debug
1815 default: 0
1816
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00001817- SPL framework
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001818 CONFIG_SPL
1819 Enable building of SPL globally.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00001820
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00001821 CONFIG_SPL_MAX_FOOTPRINT
1822 Maximum size in memory allocated to the SPL, BSS included.
1823 When defined, the linker checks that the actual memory
1824 used by SPL from _start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00001825 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00001826 must not be both defined at the same time.
1827
Tom Rini95579792012-02-14 07:29:40 +00001828 CONFIG_SPL_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00001829 Maximum size of the SPL image (text, data, rodata, and
1830 linker lists sections), BSS excluded.
1831 When defined, the linker checks that the actual size does
1832 not exceed it.
Tom Rini95579792012-02-14 07:29:40 +00001833
Scott Wood94a45bb2012-09-20 19:05:12 -05001834 CONFIG_SPL_RELOC_TEXT_BASE
1835 Address to relocate to. If unspecified, this is equal to
1836 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
1837
Tom Rini95579792012-02-14 07:29:40 +00001838 CONFIG_SPL_BSS_START_ADDR
1839 Link address for the BSS within the SPL binary.
1840
1841 CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00001842 Maximum size in memory allocated to the SPL BSS.
1843 When defined, the linker checks that the actual memory used
1844 by SPL from __bss_start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00001845 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00001846 must not be both defined at the same time.
Tom Rini95579792012-02-14 07:29:40 +00001847
1848 CONFIG_SPL_STACK
1849 Adress of the start of the stack SPL will use
1850
Albert ARIBAUD \(3ADEV\)8c80eb32015-03-31 11:40:50 +02001851 CONFIG_SPL_PANIC_ON_RAW_IMAGE
1852 When defined, SPL will panic() if the image it has
1853 loaded does not have a signature.
1854 Defining this is useful when code which loads images
1855 in SPL cannot guarantee that absolutely all read errors
1856 will be caught.
1857 An example is the LPC32XX MLC NAND driver, which will
1858 consider that a completely unreadable NAND block is bad,
1859 and thus should be skipped silently.
1860
Scott Wood94a45bb2012-09-20 19:05:12 -05001861 CONFIG_SPL_RELOC_STACK
1862 Adress of the start of the stack SPL will use after
1863 relocation. If unspecified, this is equal to
1864 CONFIG_SPL_STACK.
1865
Tom Rini95579792012-02-14 07:29:40 +00001866 CONFIG_SYS_SPL_MALLOC_START
1867 Starting address of the malloc pool used in SPL.
Fabio Estevam9ac4fc82015-11-12 12:30:19 -02001868 When this option is set the full malloc is used in SPL and
1869 it is set up by spl_init() and before that, the simple malloc()
1870 can be used if CONFIG_SYS_MALLOC_F is defined.
Tom Rini95579792012-02-14 07:29:40 +00001871
1872 CONFIG_SYS_SPL_MALLOC_SIZE
1873 The size of the malloc pool used in SPL.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00001874
Tom Rini861a86f2012-08-13 11:37:56 -07001875 CONFIG_SPL_DISPLAY_PRINT
1876 For ARM, enable an optional function to print more information
1877 about the running system.
1878
Scott Wood4b919722012-09-20 16:35:21 -05001879 CONFIG_SPL_INIT_MINIMAL
1880 Arch init code should be built for a very small image
1881
Peter Korsgaard2b75b0a2013-05-13 08:36:29 +00001882 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
1883 Sector to load kernel uImage from when MMC is being
1884 used in raw mode (for Falcon mode)
1885
1886 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
1887 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
1888 Sector and number of sectors to load kernel argument
1889 parameters from when MMC is being used in raw mode
1890 (for falcon mode)
1891
Guillaume GARDETfae81c72014-10-15 17:53:13 +02001892 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
1893 Filename to read to load U-Boot when reading from filesystem
1894
1895 CONFIG_SPL_FS_LOAD_KERNEL_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00001896 Filename to read to load kernel uImage when reading
Guillaume GARDETfae81c72014-10-15 17:53:13 +02001897 from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00001898
Guillaume GARDETfae81c72014-10-15 17:53:13 +02001899 CONFIG_SPL_FS_LOAD_ARGS_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00001900 Filename to read to load kernel argument parameters
Guillaume GARDETfae81c72014-10-15 17:53:13 +02001901 when reading from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00001902
Scott Wood06f60ae2012-12-06 13:33:17 +00001903 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
1904 Set this for NAND SPL on PPC mpc83xx targets, so that
1905 start.S waits for the rest of the SPL to load before
1906 continuing (the hardware starts execution after just
1907 loading the first page rather than the full 4K).
1908
Prabhakar Kushwaha651fcf62014-04-08 19:12:31 +05301909 CONFIG_SPL_SKIP_RELOCATE
1910 Avoid SPL relocation
1911
Jörg Krause15e207f2018-01-14 19:26:38 +01001912 CONFIG_SPL_NAND_IDENT
1913 SPL uses the chip ID list to identify the NAND flash.
1914 Requires CONFIG_SPL_NAND_BASE.
1915
Thomas Gleixner6f4e7d32016-07-12 20:28:12 +02001916 CONFIG_SPL_UBI
1917 Support for a lightweight UBI (fastmap) scanner and
1918 loader
1919
Heiko Schocher0c3117b2014-10-31 08:31:00 +01001920 CONFIG_SPL_NAND_RAW_ONLY
1921 Support to boot only raw u-boot.bin images. Use this only
1922 if you need to save space.
1923
Ying Zhang7c8eea52013-08-16 15:16:12 +08001924 CONFIG_SPL_COMMON_INIT_DDR
1925 Set for common ddr init with serial presence detect in
1926 SPL binary.
1927
Tom Rini95579792012-02-14 07:29:40 +00001928 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
1929 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
1930 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
1931 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
1932 CONFIG_SYS_NAND_ECCBYTES
1933 Defines the size and behavior of the NAND that SPL uses
Scott Wood7d4b7952012-09-21 18:35:27 -05001934 to read U-Boot
Tom Rini95579792012-02-14 07:29:40 +00001935
Scott Wood7d4b7952012-09-21 18:35:27 -05001936 CONFIG_SYS_NAND_U_BOOT_DST
1937 Location in memory to load U-Boot to
1938
1939 CONFIG_SYS_NAND_U_BOOT_SIZE
1940 Size of image to load
Tom Rini95579792012-02-14 07:29:40 +00001941
1942 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood7d4b7952012-09-21 18:35:27 -05001943 Entry point in loaded image to jump to
Tom Rini95579792012-02-14 07:29:40 +00001944
1945 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
1946 Define this if you need to first read the OOB and then the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001947 data. This is used, for example, on davinci platforms.
Tom Rini95579792012-02-14 07:29:40 +00001948
Pavel Machekc57b9532012-08-30 22:42:11 +02001949 CONFIG_SPL_RAM_DEVICE
1950 Support for running image already present in ram, in SPL binary
1951
Scott Wood74752ba2012-12-06 13:33:16 +00001952 CONFIG_SPL_PAD_TO
Benoît Thébaudeau6113d3f2013-04-11 09:35:49 +00001953 Image offset to which the SPL should be padded before appending
1954 the SPL payload. By default, this is defined as
1955 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
1956 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
1957 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Scott Wood74752ba2012-12-06 13:33:16 +00001958
Scott Woodca2fca22012-09-21 16:27:32 -05001959 CONFIG_SPL_TARGET
1960 Final target image containing SPL and payload. Some SPLs
1961 use an arch-specific makefile fragment instead, for
1962 example if more than one image needs to be produced.
1963
Marek Vasutb527b9c2018-05-13 00:22:52 +02001964 CONFIG_SPL_FIT_PRINT
Simon Glass87ebee32013-05-08 08:05:59 +00001965 Printing information about a FIT image adds quite a bit of
1966 code to SPL. So this is normally disabled in SPL. Use this
1967 option to re-enable it. This will affect the output of the
1968 bootm command when booting a FIT image.
1969
Ying Zhang3aa29de2013-08-16 15:16:15 +08001970- TPL framework
1971 CONFIG_TPL
1972 Enable building of TPL globally.
1973
1974 CONFIG_TPL_PAD_TO
1975 Image offset to which the TPL should be padded before appending
1976 the TPL payload. By default, this is defined as
Wolfgang Denk93e14592013-10-04 17:43:24 +02001977 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
1978 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
1979 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Ying Zhang3aa29de2013-08-16 15:16:15 +08001980
wdenka8c7c702003-12-06 19:49:23 +00001981- Interrupt support (PPC):
1982
wdenkd4ca31c2004-01-02 14:00:00 +00001983 There are common interrupt_init() and timer_interrupt()
1984 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001985 for CPU specific initialization. interrupt_init_cpu()
wdenkd4ca31c2004-01-02 14:00:00 +00001986 should set decrementer_count to appropriate value. If
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001987 CPU resets decrementer automatically after interrupt
wdenkd4ca31c2004-01-02 14:00:00 +00001988 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001989 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenkd4ca31c2004-01-02 14:00:00 +00001990 specific handling. If board has watchdog / status_led
1991 / other_activity_monitor it works automatically from
1992 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00001993
wdenkc6097192002-11-03 00:24:07 +00001994
Helmut Raiger9660e442011-10-20 04:19:47 +00001995Board initialization settings:
1996------------------------------
1997
1998During Initialization u-boot calls a number of board specific functions
1999to allow the preparation of board specific prerequisites, e.g. pin setup
2000before drivers are initialized. To enable these callbacks the
2001following configuration macros have to be defined. Currently this is
2002architecture specific, so please check arch/your_architecture/lib/board.c
2003typically in board_init_f() and board_init_r().
2004
2005- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2006- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2007- CONFIG_BOARD_LATE_INIT: Call board_late_init()
2008- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
wdenkc6097192002-11-03 00:24:07 +00002009
wdenkc6097192002-11-03 00:24:07 +00002010Configuration Settings:
2011-----------------------
2012
Simon Glass4d979bf2019-12-28 10:45:10 -07002013- MEM_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
York Sun4d1fd7f2014-02-26 17:03:19 -08002014 Optionally it can be defined to support 64-bit memory commands.
2015
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002016- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00002017 undefine this when you're short of memory.
2018
Peter Tyser2fb26042009-01-27 18:03:12 -06002019- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2020 width of the commands listed in the 'help' command output.
2021
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002022- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00002023 prompt for user input.
2024
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002025- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
wdenkc6097192002-11-03 00:24:07 +00002026
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002027- CONFIG_SYS_PBSIZE: Buffer size for Console output
wdenkc6097192002-11-03 00:24:07 +00002028
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002029- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
wdenkc6097192002-11-03 00:24:07 +00002030
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002031- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
wdenkc6097192002-11-03 00:24:07 +00002032 the application (usually a Linux kernel) when it is
2033 booted
2034
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002035- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00002036 List of legal baudrate settings for this board.
2037
York Sune8149522015-12-04 11:57:07 -08002038- CONFIG_SYS_MEM_RESERVE_SECURE
York Sune61a7532016-06-24 16:46:18 -07002039 Only implemented for ARMv8 for now.
York Sune8149522015-12-04 11:57:07 -08002040 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2041 is substracted from total RAM and won't be reported to OS.
2042 This memory can be used as secure memory. A variable
York Sune61a7532016-06-24 16:46:18 -07002043 gd->arch.secure_ram is used to track the location. In systems
York Sune8149522015-12-04 11:57:07 -08002044 the RAM base is not zero, or RAM is divided into banks,
2045 this variable needs to be recalcuated to get the address.
2046
York Sunaabd7dd2015-12-07 11:05:29 -08002047- CONFIG_SYS_MEM_TOP_HIDE:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002048 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
Stefan Roese14f73ca2008-03-26 10:14:11 +01002049 this specified memory area will get subtracted from the top
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002050 (end) of RAM and won't get "touched" at all by U-Boot. By
Stefan Roese14f73ca2008-03-26 10:14:11 +01002051 fixing up gd->ram_size the Linux kernel should gets passed
2052 the now "corrected" memory size and won't touch it either.
2053 This should work for arch/ppc and arch/powerpc. Only Linux
Stefan Roese5e12e752008-03-28 11:02:53 +01002054 board ports in arch/powerpc with bootwrapper support that
Stefan Roese14f73ca2008-03-26 10:14:11 +01002055 recalculate the memory size from the SDRAM controller setup
Stefan Roese5e12e752008-03-28 11:02:53 +01002056 will have to get fixed in Linux additionally.
Stefan Roese14f73ca2008-03-26 10:14:11 +01002057
2058 This option can be used as a workaround for the 440EPx/GRx
2059 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2060 be touched.
2061
2062 WARNING: Please make sure that this value is a multiple of
2063 the Linux page size (normally 4k). If this is not the case,
2064 then the end address of the Linux memory will be located at a
2065 non page size aligned address and this could cause major
2066 problems.
2067
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002068- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00002069 Enable temporary baudrate change while serial download
2070
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002071- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00002072 Physical start address of SDRAM. _Must_ be 0 here.
2073
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002074- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00002075 Physical start address of Flash memory.
2076
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002077- CONFIG_SYS_MONITOR_BASE:
wdenkc6097192002-11-03 00:24:07 +00002078 Physical start address of boot monitor code (set by
2079 make config files to be same as the text base address
Wolfgang Denk14d0a022010-10-07 21:51:12 +02002080 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002081 CONFIG_SYS_FLASH_BASE when booting from flash.
wdenkc6097192002-11-03 00:24:07 +00002082
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002083- CONFIG_SYS_MONITOR_LEN:
wdenk8bde7f72003-06-27 21:31:46 +00002084 Size of memory reserved for monitor code, used to
2085 determine _at_compile_time_ (!) if the environment is
2086 embedded within the U-Boot image, or in a separate
2087 flash sector.
wdenkc6097192002-11-03 00:24:07 +00002088
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002089- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00002090 Size of DRAM reserved for malloc() use.
2091
Simon Glassd59476b2014-07-10 22:23:28 -06002092- CONFIG_SYS_MALLOC_F_LEN
2093 Size of the malloc() pool for use before relocation. If
2094 this is defined, then a very simple malloc() implementation
2095 will become available before relocation. The address is just
2096 below the global data, and the stack is moved down to make
2097 space.
2098
2099 This feature allocates regions with increasing addresses
2100 within the region. calloc() is supported, but realloc()
2101 is not available. free() is supported but does nothing.
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002102 The memory will be freed (or in fact just forgotten) when
Simon Glassd59476b2014-07-10 22:23:28 -06002103 U-Boot relocates itself.
2104
Simon Glass38687ae2014-11-10 17:16:54 -07002105- CONFIG_SYS_MALLOC_SIMPLE
2106 Provides a simple and small malloc() and calloc() for those
2107 boards which do not use the full malloc in SPL (which is
2108 enabled with CONFIG_SYS_SPL_MALLOC_START).
2109
Thierry Reding1dfdd9b2014-12-09 22:25:22 -07002110- CONFIG_SYS_NONCACHED_MEMORY:
2111 Size of non-cached memory area. This area of memory will be
2112 typically located right below the malloc() area and mapped
2113 uncached in the MMU. This is useful for drivers that would
2114 otherwise require a lot of explicit cache maintenance. For
2115 some drivers it's also impossible to properly maintain the
2116 cache. For example if the regions that need to be flushed
2117 are not a multiple of the cache-line size, *and* padding
2118 cannot be allocated between the regions to align them (i.e.
2119 if the HW requires a contiguous array of regions, and the
2120 size of each region is not cache-aligned), then a flush of
2121 one region may result in overwriting data that hardware has
2122 written to another region in the same cache-line. This can
2123 happen for example in network drivers where descriptors for
2124 buffers are typically smaller than the CPU cache-line (e.g.
2125 16 bytes vs. 32 or 64 bytes).
2126
2127 Non-cached memory is only supported on 32-bit ARM at present.
2128
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002129- CONFIG_SYS_BOOTM_LEN:
Stefan Roese15940c92006-03-13 11:16:36 +01002130 Normally compressed uImages are limited to an
2131 uncompressed size of 8 MBytes. If this is not enough,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002132 you can define CONFIG_SYS_BOOTM_LEN in your board config file
Stefan Roese15940c92006-03-13 11:16:36 +01002133 to adjust this setting to your needs.
2134
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002135- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00002136 Maximum size of memory mapped by the startup code of
2137 the Linux kernel; all data that must be processed by
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002138 the Linux kernel (bd_info, boot arguments, FDT blob if
2139 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002140 environment variable is defined and non-zero. In such case
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002141 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002142 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likelyc3624e62011-03-28 09:58:43 +00002143 variable "bootm_mapsize" will override the value of
2144 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2145 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00002146
John Rigbyfca43cc2010-10-13 13:57:35 -06002147- CONFIG_SYS_BOOT_RAMDISK_HIGH:
2148 Enable initrd_high functionality. If defined then the
2149 initrd_high feature is enabled and the bootm ramdisk subcommand
2150 is enabled.
2151
2152- CONFIG_SYS_BOOT_GET_CMDLINE:
2153 Enables allocating and saving kernel cmdline in space between
2154 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2155
2156- CONFIG_SYS_BOOT_GET_KBD:
2157 Enables allocating and saving a kernel copy of the bd_info in
2158 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2159
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002160- CONFIG_SYS_MAX_FLASH_BANKS:
wdenkc6097192002-11-03 00:24:07 +00002161 Max number of Flash memory banks
2162
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002163- CONFIG_SYS_MAX_FLASH_SECT:
wdenkc6097192002-11-03 00:24:07 +00002164 Max number of sectors on a Flash chip
2165
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002166- CONFIG_SYS_FLASH_ERASE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002167 Timeout for Flash erase operations (in ms)
2168
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002169- CONFIG_SYS_FLASH_WRITE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002170 Timeout for Flash write operations (in ms)
2171
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002172- CONFIG_SYS_FLASH_LOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002173 Timeout for Flash set sector lock bit operation (in ms)
2174
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002175- CONFIG_SYS_FLASH_UNLOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002176 Timeout for Flash clear lock bits operation (in ms)
2177
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002178- CONFIG_SYS_FLASH_PROTECTION
wdenk8564acf2003-07-14 22:13:32 +00002179 If defined, hardware flash sectors protection is used
2180 instead of U-Boot software protection.
2181
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002182- CONFIG_SYS_DIRECT_FLASH_TFTP:
wdenkc6097192002-11-03 00:24:07 +00002183
2184 Enable TFTP transfers directly to flash memory;
2185 without this option such a download has to be
2186 performed in two steps: (1) download to RAM, and (2)
2187 copy from RAM to flash.
2188
2189 The two-step approach is usually more reliable, since
2190 you can check if the download worked before you erase
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002191 the flash, but in some situations (when system RAM is
2192 too limited to allow for a temporary copy of the
wdenkc6097192002-11-03 00:24:07 +00002193 downloaded image) this option may be very useful.
2194
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002195- CONFIG_SYS_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00002196 Define if the flash driver uses extra elements in the
wdenk5653fc32004-02-08 22:55:38 +00002197 common flash structure for storing flash geometry.
2198
Jean-Christophe PLAGNIOL-VILLARD00b18832008-08-13 01:40:42 +02002199- CONFIG_FLASH_CFI_DRIVER
wdenk5653fc32004-02-08 22:55:38 +00002200 This option also enables the building of the cfi_flash driver
2201 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00002202
Piotr Ziecik91809ed2008-11-17 15:57:58 +01002203- CONFIG_FLASH_CFI_MTD
2204 This option enables the building of the cfi_mtd driver
2205 in the drivers directory. The driver exports CFI flash
2206 to the MTD layer.
2207
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002208- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski96ef8312008-04-03 13:36:02 +02002209 Use buffered writes to flash.
2210
2211- CONFIG_FLASH_SPANSION_S29WS_N
2212 s29ws-n MirrorBit flash has non-standard addresses for buffered
2213 write commands.
2214
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002215- CONFIG_SYS_FLASH_QUIET_TEST
Stefan Roese5568e612005-11-22 13:20:42 +01002216 If this option is defined, the common CFI flash doesn't
2217 print it's warning upon not recognized FLASH banks. This
2218 is useful, if some of the configured banks are only
2219 optionally available.
2220
Jerry Van Baren9a042e92008-03-08 13:48:01 -05002221- CONFIG_FLASH_SHOW_PROGRESS
2222 If defined (must be an integer), print out countdown
2223 digits and dots. Recommended value: 45 (9..1) for 80
2224 column displays, 15 (3..1) for 40 column displays.
2225
Stefan Roese352ef3f2013-04-04 15:53:14 +02002226- CONFIG_FLASH_VERIFY
2227 If defined, the content of the flash (destination) is compared
2228 against the source after the write operation. An error message
2229 will be printed when the contents are not identical.
2230 Please note that this option is useless in nearly all cases,
2231 since such flash programming errors usually are detected earlier
2232 while unprotecting/erasing/programming. Please only enable
2233 this option if you really know what you are doing.
2234
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002235- CONFIG_SYS_RX_ETH_BUFFER:
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002236 Defines the number of Ethernet receive buffers. On some
2237 Ethernet controllers it is recommended to set this value
stroese53cf9432003-06-05 15:39:44 +00002238 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2239 buffers can be full shortly after enabling the interface
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002240 on high Ethernet traffic.
stroese53cf9432003-06-05 15:39:44 +00002241 Defaults to 4 if not defined.
2242
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002243- CONFIG_ENV_MAX_ENTRIES
2244
Wolfgang Denk071bc922010-10-27 22:48:30 +02002245 Maximum number of entries in the hash table that is used
2246 internally to store the environment settings. The default
2247 setting is supposed to be generous and should work in most
2248 cases. This setting can be used to tune behaviour; see
2249 lib/hashtable.c for details.
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002250
Joe Hershberger25980902012-12-11 22:16:31 -06002251- CONFIG_ENV_FLAGS_LIST_DEFAULT
2252- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002253 Enable validation of the values given to environment variables when
Joe Hershberger25980902012-12-11 22:16:31 -06002254 calling env set. Variables can be restricted to only decimal,
2255 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
2256 the variables can also be restricted to IP address or MAC address.
2257
2258 The format of the list is:
2259 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002260 access_attribute = [a|r|o|c]
2261 attributes = type_attribute[access_attribute]
Joe Hershberger25980902012-12-11 22:16:31 -06002262 entry = variable_name[:attributes]
2263 list = entry[,list]
2264
2265 The type attributes are:
2266 s - String (default)
2267 d - Decimal
2268 x - Hexadecimal
2269 b - Boolean ([1yYtT|0nNfF])
2270 i - IP address
2271 m - MAC address
2272
Joe Hershberger267541f2012-12-11 22:16:34 -06002273 The access attributes are:
2274 a - Any (default)
2275 r - Read-only
2276 o - Write-once
2277 c - Change-default
2278
Joe Hershberger25980902012-12-11 22:16:31 -06002279 - CONFIG_ENV_FLAGS_LIST_DEFAULT
2280 Define this to a list (string) to define the ".flags"
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002281 environment variable in the default or embedded environment.
Joe Hershberger25980902012-12-11 22:16:31 -06002282
2283 - CONFIG_ENV_FLAGS_LIST_STATIC
2284 Define this to a list (string) to define validation that
2285 should be done if an entry is not found in the ".flags"
2286 environment variable. To override a setting in the static
2287 list, simply add an entry for the same variable name to the
2288 ".flags" variable.
2289
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05002290 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
2291 regular expression. This allows multiple variables to define the same
2292 flags without explicitly listing them for each variable.
2293
wdenkc6097192002-11-03 00:24:07 +00002294The following definitions that deal with the placement and management
2295of environment data (variable area); in general, we support the
2296following configurations:
2297
Mike Frysingerc3eb3fe2011-07-08 10:44:25 +00002298- CONFIG_BUILD_ENVCRC:
2299
2300 Builds up envcrc with the target environment so that external utils
2301 may easily extract it and embed it in final U-Boot images.
2302
wdenkc6097192002-11-03 00:24:07 +00002303BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002304in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002305console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00002306U-Boot will hang.
2307
2308Please note that even with NVRAM we still use a copy of the
2309environment in RAM: we could work on NVRAM directly, but we want to
2310keep settings there always unmodified except somebody uses "saveenv"
2311to save the current settings.
2312
Liu Gang0a85a9e2012-03-08 00:33:20 +00002313BE CAREFUL! For some special cases, the local device can not use
2314"saveenv" command. For example, the local device will get the
Liu Gangfc54c7f2012-08-09 05:10:01 +00002315environment stored in a remote NOR flash by SRIO or PCIE link,
2316but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang0a85a9e2012-03-08 00:33:20 +00002317
Guennadi Liakhovetskib74ab732009-05-18 16:07:22 +02002318- CONFIG_NAND_ENV_DST
2319
2320 Defines address in RAM to which the nand_spl code should copy the
2321 environment. If redundant environment is used, it will be copied to
2322 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2323
Bruce Adlere881cb52007-11-02 13:15:42 -07002324Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00002325has been relocated to RAM and a RAM copy of the environment has been
Simon Glass00caae62017-08-03 12:22:12 -06002326created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00002327until then to read environment variables.
2328
wdenk85ec0bc2003-03-31 16:34:49 +00002329The environment is protected by a CRC32 checksum. Before the monitor
2330is relocated into RAM, as a result of a bad CRC you will be working
2331with the compiled-in default environment - *silently*!!! [This is
2332necessary, because the first environment variable we need is the
2333"baudrate" setting for the console - if we have a bad CRC, we don't
2334have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00002335
2336Note: once the monitor has been relocated, then it will complain if
2337the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00002338use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00002339
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002340- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
wdenk42d1f032003-10-15 23:53:47 +00002341 Echo the inverted Ethernet link state to the fault LED.
wdenkfc3e2162003-10-08 22:33:00 +00002342
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002343 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
wdenkfc3e2162003-10-08 22:33:00 +00002344 also needs to be defined.
2345
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002346- CONFIG_SYS_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00002347 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00002348
Ron Madridf5675aa2009-02-18 14:30:44 -08002349- CONFIG_NS16550_MIN_FUNCTIONS:
2350 Define this if you desire to only have use of the NS16550_init
2351 and NS16550_putc functions for the serial driver located at
2352 drivers/serial/ns16550.c. This option is useful for saving
2353 space for already greatly restricted images, including but not
2354 limited to NAND_SPL configurations.
2355
Simon Glassb2b92f52012-11-30 13:01:18 +00002356- CONFIG_DISPLAY_BOARDINFO
2357 Display information about the board that U-Boot is running on
2358 when U-Boot starts up. The board function checkboard() is called
2359 to do this.
2360
Simon Glasse2e3e2b2012-11-30 13:01:19 +00002361- CONFIG_DISPLAY_BOARDINFO_LATE
2362 Similar to the previous option, but display this information
2363 later, once stdio is running and output goes to the LCD, if
2364 present.
2365
Sascha Silbefeb85802013-08-11 16:40:43 +02002366- CONFIG_BOARD_SIZE_LIMIT:
2367 Maximum size of the U-Boot image. When defined, the
2368 build system checks that the actual size does not
2369 exceed it.
2370
wdenkc6097192002-11-03 00:24:07 +00002371Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00002372---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00002373
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002374- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00002375 Cache Line Size of the CPU.
2376
Timur Tabie46fedf2011-08-04 18:03:41 -05002377- CONFIG_SYS_CCSRBAR_DEFAULT:
2378 Default (power-on reset) physical address of CCSR on Freescale
2379 PowerPC SOCs.
2380
2381- CONFIG_SYS_CCSRBAR:
2382 Virtual address of CCSR. On a 32-bit build, this is typically
2383 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
2384
Timur Tabie46fedf2011-08-04 18:03:41 -05002385- CONFIG_SYS_CCSRBAR_PHYS:
2386 Physical address of CCSR. CCSR can be relocated to a new
2387 physical address, if desired. In this case, this macro should
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002388 be set to that address. Otherwise, it should be set to the
Timur Tabie46fedf2011-08-04 18:03:41 -05002389 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
2390 is typically relocated on 36-bit builds. It is recommended
2391 that this macro be defined via the _HIGH and _LOW macros:
2392
2393 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
2394 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
2395
2396- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002397 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
2398 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05002399 used in assembly code, so it must not contain typecasts or
2400 integer size suffixes (e.g. "ULL").
2401
2402- CONFIG_SYS_CCSRBAR_PHYS_LOW:
2403 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
2404 used in assembly code, so it must not contain typecasts or
2405 integer size suffixes (e.g. "ULL").
2406
2407- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
2408 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
2409 forced to a value that ensures that CCSR is not relocated.
2410
Macpaul Lin0abddf82011-04-11 20:45:32 +00002411- CONFIG_IDE_AHB:
2412 Most IDE controllers were designed to be connected with PCI
2413 interface. Only few of them were designed for AHB interface.
2414 When software is doing ATA command and data transfer to
2415 IDE devices through IDE-AHB controller, some additional
2416 registers accessing to these kind of IDE-AHB controller
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002417 is required.
Macpaul Lin0abddf82011-04-11 20:45:32 +00002418
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002419- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenkefe2a4d2004-12-16 21:44:03 +00002420 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy907208c2017-07-06 10:23:22 +02002421 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00002422
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002423- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00002424
wdenk7152b1d2003-09-05 23:19:14 +00002425 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00002426 initial data and stack; please note that this must be
2427 writable memory that is working WITHOUT special
2428 initialization, i. e. you CANNOT use normal RAM which
2429 will become available only after programming the
2430 memory controller and running certain initialization
2431 sequences.
2432
2433 U-Boot uses the following memory types:
Christophe Leroy907208c2017-07-06 10:23:22 +02002434 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00002435
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002436- CONFIG_SYS_GBL_DATA_OFFSET:
wdenkc6097192002-11-03 00:24:07 +00002437
2438 Offset of the initial data structure in the memory
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002439 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2440 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
wdenkc6097192002-11-03 00:24:07 +00002441 data is located at the end of the available space
Wolfgang Denk553f0982010-10-26 13:32:32 +02002442 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
Simon Glassacd51f92016-10-02 18:01:06 -06002443 GENERATED_GBL_DATA_SIZE), and the initial stack is just
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002444 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2445 CONFIG_SYS_GBL_DATA_OFFSET) downward.
wdenkc6097192002-11-03 00:24:07 +00002446
2447 Note:
2448 On the MPC824X (or other systems that use the data
2449 cache for initial memory) the address chosen for
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002450 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
wdenkc6097192002-11-03 00:24:07 +00002451 point to an otherwise UNUSED address space between
2452 the top of RAM and the start of the PCI space.
2453
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002454- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00002455
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002456- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00002457 SDRAM timing
2458
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002459- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00002460 periodic timer for refresh
2461
Kumar Galaa09b9b62010-12-30 12:09:53 -06002462- CONFIG_SYS_SRIO:
2463 Chip has SRIO or not
2464
2465- CONFIG_SRIO1:
2466 Board has SRIO 1 port available
2467
2468- CONFIG_SRIO2:
2469 Board has SRIO 2 port available
2470
Liu Gangc8b28152013-05-07 16:30:46 +08002471- CONFIG_SRIO_PCIE_BOOT_MASTER
2472 Board can support master function for Boot from SRIO and PCIE
2473
Kumar Galaa09b9b62010-12-30 12:09:53 -06002474- CONFIG_SYS_SRIOn_MEM_VIRT:
2475 Virtual Address of SRIO port 'n' memory region
2476
Simon Glass62f9b652019-11-14 12:57:09 -07002477- CONFIG_SYS_SRIOn_MEM_PHYxS:
Kumar Galaa09b9b62010-12-30 12:09:53 -06002478 Physical Address of SRIO port 'n' memory region
2479
2480- CONFIG_SYS_SRIOn_MEM_SIZE:
2481 Size of SRIO port 'n' memory region
2482
Fabio Estevam66bd1842013-04-11 09:35:34 +00002483- CONFIG_SYS_NAND_BUSWIDTH_16BIT
2484 Defined to tell the NAND controller that the NAND chip is using
2485 a 16 bit bus.
2486 Not all NAND drivers use this symbol.
Fabio Estevama430e912013-04-11 09:35:35 +00002487 Example of drivers that use it:
Miquel Raynala430fa02018-08-16 17:30:07 +02002488 - drivers/mtd/nand/raw/ndfc.c
2489 - drivers/mtd/nand/raw/mxc_nand.c
Alex Watermaneced4622011-05-19 15:08:36 -04002490
2491- CONFIG_SYS_NDFC_EBC0_CFG
2492 Sets the EBC0_CFG register for the NDFC. If not defined
2493 a default value will be used.
2494
Ben Warrenbb99ad62006-09-07 16:50:54 -04002495- CONFIG_SPD_EEPROM
Wolfgang Denk218ca722008-03-26 10:40:12 +01002496 Get DDR timing information from an I2C EEPROM. Common
2497 with pluggable memory modules such as SODIMMs
2498
Ben Warrenbb99ad62006-09-07 16:50:54 -04002499 SPD_EEPROM_ADDRESS
2500 I2C address of the SPD EEPROM
2501
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002502- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denk218ca722008-03-26 10:40:12 +01002503 If SPD EEPROM is on an I2C bus other than the first
2504 one, specify here. Note that the value must resolve
2505 to something your driver can deal with.
Ben Warrenbb99ad62006-09-07 16:50:54 -04002506
York Sun1b3e3c42011-06-07 09:42:16 +08002507- CONFIG_SYS_DDR_RAW_TIMING
2508 Get DDR timing information from other than SPD. Common with
2509 soldered DDR chips onboard without SPD. DDR raw timing
2510 parameters are extracted from datasheet and hard-coded into
2511 header files or board specific files.
2512
York Sun6f5e1dc2011-09-16 13:21:35 -07002513- CONFIG_FSL_DDR_INTERACTIVE
2514 Enable interactive DDR debugging. See doc/README.fsl-ddr.
2515
York Sune32d59a2015-01-06 13:18:55 -08002516- CONFIG_FSL_DDR_SYNC_REFRESH
2517 Enable sync of refresh for multiple controllers.
2518
York Sun4516ff82015-03-19 09:30:28 -07002519- CONFIG_FSL_DDR_BIST
2520 Enable built-in memory test for Freescale DDR controllers.
2521
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002522- CONFIG_SYS_83XX_DDR_USES_CS0
Wolfgang Denk218ca722008-03-26 10:40:12 +01002523 Only for 83xx systems. If specified, then DDR should
2524 be configured using CS0 and CS1 instead of CS2 and CS3.
Timur Tabi2ad6b512006-10-31 18:44:42 -06002525
wdenkc26e4542004-04-18 10:13:26 +00002526- CONFIG_RMII
2527 Enable RMII mode for all FECs.
2528 Note that this is a global option, we can't
2529 have one FEC in standard MII mode and another in RMII mode.
2530
wdenk5cf91d62004-04-23 20:32:05 +00002531- CONFIG_CRC32_VERIFY
2532 Add a verify option to the crc32 command.
2533 The syntax is:
2534
2535 => crc32 -v <address> <count> <crc32>
2536
2537 Where address/count indicate a memory area
2538 and crc32 is the correct crc32 which the
2539 area should have.
2540
wdenk56523f12004-07-11 17:40:54 +00002541- CONFIG_LOOPW
2542 Add the "loopw" memory command. This only takes effect if
Simon Glass493f4202017-08-04 16:34:27 -06002543 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk56523f12004-07-11 17:40:54 +00002544
Joel Johnson72732312020-01-29 09:17:18 -07002545- CONFIG_CMD_MX_CYCLIC
stroese7b466642004-12-16 18:46:55 +00002546 Add the "mdc" and "mwc" memory commands. These are cyclic
2547 "md/mw" commands.
2548 Examples:
2549
wdenkefe2a4d2004-12-16 21:44:03 +00002550 => mdc.b 10 4 500
stroese7b466642004-12-16 18:46:55 +00002551 This command will print 4 bytes (10,11,12,13) each 500 ms.
2552
wdenkefe2a4d2004-12-16 21:44:03 +00002553 => mwc.l 100 12345678 10
stroese7b466642004-12-16 18:46:55 +00002554 This command will write 12345678 to address 100 all 10 ms.
2555
wdenkefe2a4d2004-12-16 21:44:03 +00002556 This only takes effect if the memory commands are activated
Simon Glass493f4202017-08-04 16:34:27 -06002557 globally (CONFIG_CMD_MEMORY).
stroese7b466642004-12-16 18:46:55 +00002558
Aneesh V401bb302011-07-13 05:11:07 +00002559- CONFIG_SPL_BUILD
Thomas Hebb32f2ca22019-11-13 18:18:03 -08002560 Set when the currently-running compilation is for an artifact
2561 that will end up in the SPL (as opposed to the TPL or U-Boot
2562 proper). Code that needs stage-specific behavior should check
2563 this.
wdenk400558b2005-04-02 23:52:25 +00002564
Ying Zhang3aa29de2013-08-16 15:16:15 +08002565- CONFIG_TPL_BUILD
Thomas Hebb32f2ca22019-11-13 18:18:03 -08002566 Set when the currently-running compilation is for an artifact
2567 that will end up in the TPL (as opposed to the SPL or U-Boot
2568 proper). Code that needs stage-specific behavior should check
2569 this.
Ying Zhang3aa29de2013-08-16 15:16:15 +08002570
Ying Zhang5df572f2013-05-20 14:07:23 +08002571- CONFIG_SYS_MPC85XX_NO_RESETVEC
2572 Only for 85xx systems. If this variable is specified, the section
2573 .resetvec is not kept and the section .bootpg is placed in the
2574 previous 4k of the .text section.
2575
Simon Glass4213fc22013-02-24 17:33:14 +00002576- CONFIG_ARCH_MAP_SYSMEM
2577 Generally U-Boot (and in particular the md command) uses
2578 effective address. It is therefore not necessary to regard
2579 U-Boot address as virtual addresses that need to be translated
2580 to physical addresses. However, sandbox requires this, since
2581 it maintains its own little RAM buffer which contains all
2582 addressable memory. This option causes some memory accesses
2583 to be mapped through map_sysmem() / unmap_sysmem().
2584
Simon Glass588a13f2013-02-14 04:18:54 +00002585- CONFIG_X86_RESET_VECTOR
2586 If defined, the x86 reset vector code is included. This is not
2587 needed when U-Boot is running from Coreboot.
Gabe Blackb16f5212012-11-27 21:08:06 +00002588
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04002589- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
2590 Option to disable subpage write in NAND driver
2591 driver that uses this:
Miquel Raynala430fa02018-08-16 17:30:07 +02002592 drivers/mtd/nand/raw/davinci_nand.c
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04002593
Timur Tabif2717b42011-11-22 09:21:25 -06002594Freescale QE/FMAN Firmware Support:
2595-----------------------------------
2596
2597The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
2598loading of "firmware", which is encoded in the QE firmware binary format.
2599This firmware often needs to be loaded during U-Boot booting, so macros
2600are used to identify the storage device (NOR flash, SPI, etc) and the address
2601within that device.
2602
Zhao Qiangdcf1d772014-03-21 16:21:44 +08002603- CONFIG_SYS_FMAN_FW_ADDR
2604 The address in the storage device where the FMAN microcode is located. The
Tom Rinicc1e98b2019-05-12 07:59:12 -04002605 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Zhao Qiangdcf1d772014-03-21 16:21:44 +08002606 is also specified.
2607
2608- CONFIG_SYS_QE_FW_ADDR
2609 The address in the storage device where the QE microcode is located. The
Tom Rinicc1e98b2019-05-12 07:59:12 -04002610 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Timur Tabif2717b42011-11-22 09:21:25 -06002611 is also specified.
2612
2613- CONFIG_SYS_QE_FMAN_FW_LENGTH
2614 The maximum possible size of the firmware. The firmware binary format
2615 has a field that specifies the actual size of the firmware, but it
2616 might not be possible to read any part of the firmware unless some
2617 local storage is allocated to hold the entire firmware first.
2618
2619- CONFIG_SYS_QE_FMAN_FW_IN_NOR
2620 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
2621 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
2622 virtual address in NOR flash.
2623
2624- CONFIG_SYS_QE_FMAN_FW_IN_NAND
2625 Specifies that QE/FMAN firmware is located in NAND flash.
2626 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
2627
2628- CONFIG_SYS_QE_FMAN_FW_IN_MMC
2629 Specifies that QE/FMAN firmware is located on the primary SD/MMC
2630 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
2631
Liu Gang292dc6c2012-03-08 00:33:18 +00002632- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
2633 Specifies that QE/FMAN firmware is located in the remote (master)
2634 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gangfc54c7f2012-08-09 05:10:01 +00002635 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
2636 window->master inbound window->master LAW->the ucode address in
2637 master's memory space.
Timur Tabif2717b42011-11-22 09:21:25 -06002638
J. German Riverab940ca62014-06-23 15:15:55 -07002639Freescale Layerscape Management Complex Firmware Support:
2640---------------------------------------------------------
2641The Freescale Layerscape Management Complex (MC) supports the loading of
2642"firmware".
2643This firmware often needs to be loaded during U-Boot booting, so macros
2644are used to identify the storage device (NOR flash, SPI, etc) and the address
2645within that device.
2646
2647- CONFIG_FSL_MC_ENET
2648 Enable the MC driver for Layerscape SoCs.
2649
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05302650Freescale Layerscape Debug Server Support:
2651-------------------------------------------
2652The Freescale Layerscape Debug Server Support supports the loading of
2653"Debug Server firmware" and triggering SP boot-rom.
2654This firmware often needs to be loaded during U-Boot booting.
2655
York Sunc0492142015-12-07 11:08:58 -08002656- CONFIG_SYS_MC_RSV_MEM_ALIGN
2657 Define alignment of reserved memory MC requires
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05302658
Paul Kocialkowskif3f431a2015-07-26 18:48:15 +02002659Reproducible builds
2660-------------------
2661
2662In order to achieve reproducible builds, timestamps used in the U-Boot build
2663process have to be set to a fixed value.
2664
2665This is done using the SOURCE_DATE_EPOCH environment variable.
2666SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
2667option for U-Boot or an environment variable in U-Boot.
2668
2669SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
2670
wdenkc6097192002-11-03 00:24:07 +00002671Building the Software:
2672======================
2673
Wolfgang Denk218ca722008-03-26 10:40:12 +01002674Building U-Boot has been tested in several native build environments
2675and in many different cross environments. Of course we cannot support
2676all possibly existing versions of cross development tools in all
2677(potentially obsolete) versions. In case of tool chain problems we
Naoki Hayama047f6ec2020-10-08 13:17:16 +09002678recommend to use the ELDK (see https://www.denx.de/wiki/DULG/ELDK)
Wolfgang Denk218ca722008-03-26 10:40:12 +01002679which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00002680
Wolfgang Denk218ca722008-03-26 10:40:12 +01002681If you are not using a native environment, it is assumed that you
2682have GNU cross compiling tools available in your path. In this case,
2683you must set the environment variable CROSS_COMPILE in your shell.
2684Note that no changes to the Makefile or any other source files are
2685necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00002686
Wolfgang Denk218ca722008-03-26 10:40:12 +01002687 $ CROSS_COMPILE=ppc_4xx-
2688 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00002689
Wolfgang Denk218ca722008-03-26 10:40:12 +01002690U-Boot is intended to be simple to build. After installing the
2691sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00002692is done by typing:
2693
Holger Freytherab584d62014-08-04 09:26:05 +02002694 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00002695
Holger Freytherab584d62014-08-04 09:26:05 +02002696where "NAME_defconfig" is the name of one of the existing configu-
Heinrich Schuchardtecb3a0a2020-02-24 18:36:30 +01002697rations; see configs/*_defconfig for supported names.
wdenk54387ac2003-10-08 22:45:44 +00002698
Heinrich Schuchardtecb3a0a2020-02-24 18:36:30 +01002699Note: for some boards special configuration names may exist; check if
wdenk2729af92004-05-03 20:45:30 +00002700 additional information is available from the board vendor; for
2701 instance, the TQM823L systems are available without (standard)
2702 or with LCD support. You can select such additional "features"
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002703 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00002704
Holger Freytherab584d62014-08-04 09:26:05 +02002705 make TQM823L_defconfig
wdenk2729af92004-05-03 20:45:30 +00002706 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00002707
Holger Freytherab584d62014-08-04 09:26:05 +02002708 make TQM823L_LCD_defconfig
wdenk2729af92004-05-03 20:45:30 +00002709 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00002710
wdenk2729af92004-05-03 20:45:30 +00002711 etc.
wdenkc6097192002-11-03 00:24:07 +00002712
wdenkc6097192002-11-03 00:24:07 +00002713
wdenk2729af92004-05-03 20:45:30 +00002714Finally, type "make all", and you should get some working U-Boot
2715images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00002716
wdenk2729af92004-05-03 20:45:30 +00002717- "u-boot.bin" is a raw binary image
2718- "u-boot" is an image in ELF binary format
2719- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00002720
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002721By default the build is performed locally and the objects are saved
2722in the source directory. One of the two methods can be used to change
2723this behavior and build U-Boot to some external directory:
2724
27251. Add O= to the make command line invocations:
2726
2727 make O=/tmp/build distclean
Holger Freytherab584d62014-08-04 09:26:05 +02002728 make O=/tmp/build NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002729 make O=/tmp/build all
2730
Timo Ketolaadbba992014-11-06 14:39:05 +020027312. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002732
Timo Ketolaadbba992014-11-06 14:39:05 +02002733 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002734 make distclean
Holger Freytherab584d62014-08-04 09:26:05 +02002735 make NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002736 make all
2737
Timo Ketolaadbba992014-11-06 14:39:05 +02002738Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002739variable.
2740
Daniel Schwierzeck215bb1c2018-01-26 16:31:04 +01002741User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
2742setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
2743For example to treat all compiler warnings as errors:
2744
2745 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00002746
wdenk2729af92004-05-03 20:45:30 +00002747Please be aware that the Makefiles assume you are using GNU make, so
2748for instance on NetBSD you might need to use "gmake" instead of
2749native "make".
wdenkc6097192002-11-03 00:24:07 +00002750
wdenkc6097192002-11-03 00:24:07 +00002751
wdenk2729af92004-05-03 20:45:30 +00002752If the system board that you have is not listed, then you will need
2753to port U-Boot to your hardware platform. To do this, follow these
2754steps:
wdenkc6097192002-11-03 00:24:07 +00002755
Phil Sutter3c1496c2015-12-25 14:41:18 +010027561. Create a new directory to hold your board specific code. Add any
wdenk2729af92004-05-03 20:45:30 +00002757 files you need. In your board directory, you will need at least
Phil Sutter3c1496c2015-12-25 14:41:18 +01002758 the "Makefile" and a "<board>.c".
27592. Create a new configuration file "include/configs/<board>.h" for
2760 your board.
wdenk2729af92004-05-03 20:45:30 +000027613. If you're porting U-Boot to a new CPU, then also create a new
2762 directory to hold your CPU specific code. Add any files you need.
Holger Freytherab584d62014-08-04 09:26:05 +020027634. Run "make <board>_defconfig" with your new name.
wdenk2729af92004-05-03 20:45:30 +000027645. Type "make", and you should get a working "u-boot.srec" file
2765 to be installed on your target system.
27666. Debug and solve any problems that might arise.
2767 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00002768
wdenkc6097192002-11-03 00:24:07 +00002769
wdenk2729af92004-05-03 20:45:30 +00002770Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2771==============================================================
wdenkc6097192002-11-03 00:24:07 +00002772
Wolfgang Denk218ca722008-03-26 10:40:12 +01002773If you have modified U-Boot sources (for instance added a new board
2774or support for new devices, a new CPU, etc.) you are expected to
wdenk2729af92004-05-03 20:45:30 +00002775provide feedback to the other developers. The feedback normally takes
Thomas Hebb32f2ca22019-11-13 18:18:03 -08002776the form of a "patch", i.e. a context diff against a certain (latest
Wolfgang Denk218ca722008-03-26 10:40:12 +01002777official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00002778
Wolfgang Denk218ca722008-03-26 10:40:12 +01002779But before you submit such a patch, please verify that your modifi-
2780cation did not break existing code. At least make sure that *ALL* of
wdenk2729af92004-05-03 20:45:30 +00002781the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glass6de80f22016-07-27 20:33:08 -06002782just run the buildman script (tools/buildman/buildman), which will
2783configure and build U-Boot for ALL supported system. Be warned, this
2784will take a while. Please see the buildman README, or run 'buildman -H'
2785for documentation.
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002786
2787
wdenk2729af92004-05-03 20:45:30 +00002788See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00002789
wdenkc6097192002-11-03 00:24:07 +00002790
wdenk2729af92004-05-03 20:45:30 +00002791Monitor Commands - Overview:
2792============================
wdenkc6097192002-11-03 00:24:07 +00002793
wdenk2729af92004-05-03 20:45:30 +00002794go - start application at address 'addr'
2795run - run commands in an environment variable
2796bootm - boot application image from memory
2797bootp - boot image via network using BootP/TFTP protocol
Marek Vasut44f074c2012-03-14 21:52:45 +00002798bootz - boot zImage from memory
wdenk2729af92004-05-03 20:45:30 +00002799tftpboot- boot image via network using TFTP protocol
2800 and env variables "ipaddr" and "serverip"
2801 (and eventually "gatewayip")
Simon Glass1fb7cd42011-10-24 18:00:07 +00002802tftpput - upload a file via network using TFTP protocol
wdenk2729af92004-05-03 20:45:30 +00002803rarpboot- boot image via network using RARP/TFTP protocol
2804diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2805loads - load S-Record file over serial line
2806loadb - load binary file over serial line (kermit mode)
2807md - memory display
2808mm - memory modify (auto-incrementing)
2809nm - memory modify (constant address)
2810mw - memory write (fill)
Simon Glassbdded202020-06-02 19:26:49 -06002811ms - memory search
wdenk2729af92004-05-03 20:45:30 +00002812cp - memory copy
2813cmp - memory compare
2814crc32 - checksum calculation
Peter Tyser0f89c542009-04-18 22:34:03 -05002815i2c - I2C sub-system
wdenk2729af92004-05-03 20:45:30 +00002816sspi - SPI utility commands
2817base - print or set address offset
2818printenv- print environment variables
Pragnesh Patel9e9a5302020-12-22 11:30:05 +05302819pwm - control pwm channels
wdenk2729af92004-05-03 20:45:30 +00002820setenv - set environment variables
2821saveenv - save environment variables to persistent storage
2822protect - enable or disable FLASH write protection
2823erase - erase FLASH memory
2824flinfo - print FLASH memory information
Karl O. Pinc10635af2012-08-03 05:57:21 +00002825nand - NAND memory operations (see doc/README.nand)
wdenk2729af92004-05-03 20:45:30 +00002826bdinfo - print Board Info structure
2827iminfo - print header information for application image
2828coninfo - print console devices and informations
2829ide - IDE sub-system
2830loop - infinite loop on address range
wdenk56523f12004-07-11 17:40:54 +00002831loopw - infinite write loop on address range
wdenk2729af92004-05-03 20:45:30 +00002832mtest - simple RAM test
2833icache - enable or disable instruction cache
2834dcache - enable or disable data cache
2835reset - Perform RESET of the CPU
2836echo - echo args to console
2837version - print monitor version
2838help - print online help
2839? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00002840
wdenkc6097192002-11-03 00:24:07 +00002841
wdenk2729af92004-05-03 20:45:30 +00002842Monitor Commands - Detailed Description:
2843========================================
wdenkc6097192002-11-03 00:24:07 +00002844
wdenk2729af92004-05-03 20:45:30 +00002845TODO.
wdenkc6097192002-11-03 00:24:07 +00002846
wdenk2729af92004-05-03 20:45:30 +00002847For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00002848
2849
wdenk2729af92004-05-03 20:45:30 +00002850Note for Redundant Ethernet Interfaces:
2851=======================================
wdenkf07771c2003-05-28 08:06:31 +00002852
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002853Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk2729af92004-05-03 20:45:30 +00002854such configurations and is capable of automatic selection of a
2855"working" interface when needed. MAC assignment works as follows:
wdenkf07771c2003-05-28 08:06:31 +00002856
wdenk2729af92004-05-03 20:45:30 +00002857Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2858MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2859"eth1addr" (=>eth1), "eth2addr", ...
wdenkf07771c2003-05-28 08:06:31 +00002860
wdenk2729af92004-05-03 20:45:30 +00002861If the network interface stores some valid MAC address (for instance
2862in SROM), this is used as default address if there is NO correspon-
2863ding setting in the environment; if the corresponding environment
2864variable is set, this overrides the settings in the card; that means:
wdenkf07771c2003-05-28 08:06:31 +00002865
wdenk2729af92004-05-03 20:45:30 +00002866o If the SROM has a valid MAC address, and there is no address in the
2867 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00002868
wdenk2729af92004-05-03 20:45:30 +00002869o If there is no valid address in the SROM, and a definition in the
2870 environment exists, then the value from the environment variable is
2871 used.
wdenkc6097192002-11-03 00:24:07 +00002872
wdenk2729af92004-05-03 20:45:30 +00002873o If both the SROM and the environment contain a MAC address, and
2874 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00002875
wdenk2729af92004-05-03 20:45:30 +00002876o If both the SROM and the environment contain a MAC address, and the
2877 addresses differ, the value from the environment is used and a
2878 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00002879
wdenk2729af92004-05-03 20:45:30 +00002880o If neither SROM nor the environment contain a MAC address, an error
Joe Hershbergerbef10142015-05-04 14:55:13 -05002881 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
2882 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00002883
Ben Warrenecee9322010-04-26 11:11:46 -07002884If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002885will be programmed into hardware as part of the initialization process. This
Ben Warrenecee9322010-04-26 11:11:46 -07002886may be skipped by setting the appropriate 'ethmacskip' environment variable.
2887The naming convention is as follows:
2888"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00002889
wdenk2729af92004-05-03 20:45:30 +00002890Image Formats:
2891==============
wdenkc6097192002-11-03 00:24:07 +00002892
Marian Balakowicz3310c542008-03-12 12:13:13 +01002893U-Boot is capable of booting (and performing other auxiliary operations on)
2894images in two formats:
2895
2896New uImage format (FIT)
2897-----------------------
2898
2899Flexible and powerful format based on Flattened Image Tree -- FIT (similar
2900to Flattened Device Tree). It allows the use of images with multiple
2901components (several kernels, ramdisks, etc.), with contents protected by
2902SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
2903
2904
2905Old uImage format
2906-----------------
2907
2908Old image format is based on binary files which can be basically anything,
2909preceded by a special header; see the definitions in include/image.h for
2910details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00002911
wdenk2729af92004-05-03 20:45:30 +00002912* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2913 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyserf5ed9e32008-09-08 14:56:49 -05002914 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
Thomas Huth0797e732021-11-13 18:13:50 +01002915 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, INTEGRITY).
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03002916* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Macpaul Linafc1ce82011-10-19 20:41:11 +00002917 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03002918 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
wdenk2729af92004-05-03 20:45:30 +00002919* Compression Type (uncompressed, gzip, bzip2)
2920* Load Address
2921* Entry Point
2922* Image Name
2923* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00002924
wdenk2729af92004-05-03 20:45:30 +00002925The header is marked by a special Magic Number, and both the header
2926and the data portions of the image are secured against corruption by
2927CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00002928
wdenkc6097192002-11-03 00:24:07 +00002929
wdenk2729af92004-05-03 20:45:30 +00002930Linux Support:
2931==============
wdenkc6097192002-11-03 00:24:07 +00002932
wdenk2729af92004-05-03 20:45:30 +00002933Although U-Boot should support any OS or standalone application
2934easily, the main focus has always been on Linux during the design of
2935U-Boot.
wdenkc6097192002-11-03 00:24:07 +00002936
wdenk2729af92004-05-03 20:45:30 +00002937U-Boot includes many features that so far have been part of some
2938special "boot loader" code within the Linux kernel. Also, any
2939"initrd" images to be used are no longer part of one big Linux image;
2940instead, kernel and "initrd" are separate images. This implementation
2941serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00002942
wdenk2729af92004-05-03 20:45:30 +00002943- the same features can be used for other OS or standalone
2944 applications (for instance: using compressed images to reduce the
2945 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00002946
wdenk2729af92004-05-03 20:45:30 +00002947- it becomes much easier to port new Linux kernel versions because
2948 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00002949
wdenk2729af92004-05-03 20:45:30 +00002950- the same Linux kernel image can now be used with different "initrd"
2951 images; of course this also means that different kernel images can
2952 be run with the same "initrd". This makes testing easier (you don't
2953 have to build a new "zImage.initrd" Linux image when you just
2954 change a file in your "initrd"). Also, a field-upgrade of the
2955 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00002956
wdenkc6097192002-11-03 00:24:07 +00002957
wdenk2729af92004-05-03 20:45:30 +00002958Linux HOWTO:
2959============
wdenkc6097192002-11-03 00:24:07 +00002960
wdenk2729af92004-05-03 20:45:30 +00002961Porting Linux to U-Boot based systems:
2962---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00002963
wdenk2729af92004-05-03 20:45:30 +00002964U-Boot cannot save you from doing all the necessary modifications to
2965configure the Linux device drivers for use with your target hardware
2966(no, we don't intend to provide a full virtual machine interface to
2967Linux :-).
wdenkc6097192002-11-03 00:24:07 +00002968
Stefan Roesea47a12b2010-04-15 16:07:28 +02002969But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00002970
wdenk2729af92004-05-03 20:45:30 +00002971Just make sure your machine specific header file (for instance
2972include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg1dc30692008-09-07 20:18:27 +02002973Information structure as we define in include/asm-<arch>/u-boot.h,
2974and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002975as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00002976
Simon Glass2eb31b12014-06-11 23:29:46 -06002977Note that U-Boot now has a driver model, a unified model for drivers.
2978If you are adding a new driver, plumb it into driver model. If there
2979is no uclass available, you are encouraged to create one. See
2980doc/driver-model.
2981
wdenkc6097192002-11-03 00:24:07 +00002982
wdenk2729af92004-05-03 20:45:30 +00002983Configuring the Linux kernel:
2984-----------------------------
wdenkc6097192002-11-03 00:24:07 +00002985
wdenk2729af92004-05-03 20:45:30 +00002986No specific requirements for U-Boot. Make sure you have some root
2987device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00002988
wdenkc6097192002-11-03 00:24:07 +00002989
wdenk2729af92004-05-03 20:45:30 +00002990Building a Linux Image:
2991-----------------------
wdenkc6097192002-11-03 00:24:07 +00002992
wdenk2729af92004-05-03 20:45:30 +00002993With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2994not used. If you use recent kernel source, a new build target
2995"uImage" will exist which automatically builds an image usable by
2996U-Boot. Most older kernels also have support for a "pImage" target,
2997which was introduced for our predecessor project PPCBoot and uses a
2998100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00002999
wdenk2729af92004-05-03 20:45:30 +00003000Example:
wdenkc6097192002-11-03 00:24:07 +00003001
Holger Freytherab584d62014-08-04 09:26:05 +02003002 make TQM850L_defconfig
wdenk2729af92004-05-03 20:45:30 +00003003 make oldconfig
3004 make dep
3005 make uImage
wdenkc6097192002-11-03 00:24:07 +00003006
wdenk2729af92004-05-03 20:45:30 +00003007The "uImage" build target uses a special tool (in 'tools/mkimage') to
3008encapsulate a compressed Linux kernel image with header information,
3009CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00003010
wdenk2729af92004-05-03 20:45:30 +00003011* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00003012
wdenk2729af92004-05-03 20:45:30 +00003013* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00003014
wdenk2729af92004-05-03 20:45:30 +00003015 ${CROSS_COMPILE}-objcopy -O binary \
3016 -R .note -R .comment \
3017 -S vmlinux linux.bin
wdenkc6097192002-11-03 00:24:07 +00003018
wdenk2729af92004-05-03 20:45:30 +00003019* compress the binary image:
wdenkc6097192002-11-03 00:24:07 +00003020
wdenk2729af92004-05-03 20:45:30 +00003021 gzip -9 linux.bin
wdenkc6097192002-11-03 00:24:07 +00003022
wdenk2729af92004-05-03 20:45:30 +00003023* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00003024
wdenk2729af92004-05-03 20:45:30 +00003025 mkimage -A ppc -O linux -T kernel -C gzip \
3026 -a 0 -e 0 -n "Linux Kernel Image" \
3027 -d linux.bin.gz uImage
wdenk24ee89b2002-11-03 17:56:27 +00003028
wdenk24ee89b2002-11-03 17:56:27 +00003029
wdenk2729af92004-05-03 20:45:30 +00003030The "mkimage" tool can also be used to create ramdisk images for use
3031with U-Boot, either separated from the Linux kernel image, or
3032combined into one file. "mkimage" encapsulates the images with a 64
3033byte header containing information about target architecture,
3034operating system, image type, compression method, entry points, time
3035stamp, CRC32 checksums, etc.
wdenk24ee89b2002-11-03 17:56:27 +00003036
wdenk2729af92004-05-03 20:45:30 +00003037"mkimage" can be called in two ways: to verify existing images and
3038print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00003039
wdenk2729af92004-05-03 20:45:30 +00003040In the first form (with "-l" option) mkimage lists the information
3041contained in the header of an existing U-Boot image; this includes
3042checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00003043
wdenk2729af92004-05-03 20:45:30 +00003044 tools/mkimage -l image
3045 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00003046
wdenk2729af92004-05-03 20:45:30 +00003047The second form (with "-d" option) is used to build a U-Boot image
3048from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00003049
wdenk2729af92004-05-03 20:45:30 +00003050 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3051 -n name -d data_file image
3052 -A ==> set architecture to 'arch'
3053 -O ==> set operating system to 'os'
3054 -T ==> set image type to 'type'
3055 -C ==> set compression type 'comp'
3056 -a ==> set load address to 'addr' (hex)
3057 -e ==> set entry point to 'ep' (hex)
3058 -n ==> set image name to 'name'
3059 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00003060
wdenk69459792004-05-29 16:53:29 +00003061Right now, all Linux kernels for PowerPC systems use the same load
3062address (0x00000000), but the entry point address depends on the
3063kernel version:
wdenkc6097192002-11-03 00:24:07 +00003064
wdenk2729af92004-05-03 20:45:30 +00003065- 2.2.x kernels have the entry point at 0x0000000C,
3066- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00003067
wdenk2729af92004-05-03 20:45:30 +00003068So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00003069
wdenk2729af92004-05-03 20:45:30 +00003070 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3071 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02003072 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk2729af92004-05-03 20:45:30 +00003073 > examples/uImage.TQM850L
3074 Image Name: 2.4.4 kernel for TQM850L
3075 Created: Wed Jul 19 02:34:59 2000
3076 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3077 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3078 Load Address: 0x00000000
3079 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003080
wdenk2729af92004-05-03 20:45:30 +00003081To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00003082
wdenk2729af92004-05-03 20:45:30 +00003083 -> tools/mkimage -l examples/uImage.TQM850L
3084 Image Name: 2.4.4 kernel for TQM850L
3085 Created: Wed Jul 19 02:34:59 2000
3086 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3087 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3088 Load Address: 0x00000000
3089 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003090
wdenk2729af92004-05-03 20:45:30 +00003091NOTE: for embedded systems where boot time is critical you can trade
3092speed for memory and install an UNCOMPRESSED image instead: this
3093needs more space in Flash, but boots much faster since it does not
3094need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00003095
Stefan Roesea47a12b2010-04-15 16:07:28 +02003096 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk2729af92004-05-03 20:45:30 +00003097 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3098 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02003099 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk2729af92004-05-03 20:45:30 +00003100 > examples/uImage.TQM850L-uncompressed
3101 Image Name: 2.4.4 kernel for TQM850L
3102 Created: Wed Jul 19 02:34:59 2000
3103 Image Type: PowerPC Linux Kernel Image (uncompressed)
3104 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3105 Load Address: 0x00000000
3106 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003107
wdenkc6097192002-11-03 00:24:07 +00003108
wdenk2729af92004-05-03 20:45:30 +00003109Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3110when your kernel is intended to use an initial ramdisk:
wdenkdb01a2e2004-04-15 23:14:49 +00003111
wdenk2729af92004-05-03 20:45:30 +00003112 -> tools/mkimage -n 'Simple Ramdisk Image' \
3113 > -A ppc -O linux -T ramdisk -C gzip \
3114 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3115 Image Name: Simple Ramdisk Image
3116 Created: Wed Jan 12 14:01:50 2000
3117 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3118 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3119 Load Address: 0x00000000
3120 Entry Point: 0x00000000
wdenkdb01a2e2004-04-15 23:14:49 +00003121
Tyler Hickse157a112020-10-26 10:40:24 -05003122The "dumpimage" tool can be used to disassemble or list the contents of images
3123built by mkimage. See dumpimage's help output (-h) for details.
wdenkdb01a2e2004-04-15 23:14:49 +00003124
wdenk2729af92004-05-03 20:45:30 +00003125Installing a Linux Image:
3126-------------------------
wdenkdb01a2e2004-04-15 23:14:49 +00003127
wdenk2729af92004-05-03 20:45:30 +00003128To downloading a U-Boot image over the serial (console) interface,
3129you must convert the image to S-Record format:
wdenkdb01a2e2004-04-15 23:14:49 +00003130
wdenk2729af92004-05-03 20:45:30 +00003131 objcopy -I binary -O srec examples/image examples/image.srec
wdenkdb01a2e2004-04-15 23:14:49 +00003132
wdenk2729af92004-05-03 20:45:30 +00003133The 'objcopy' does not understand the information in the U-Boot
3134image header, so the resulting S-Record file will be relative to
3135address 0x00000000. To load it to a given address, you need to
3136specify the target address as 'offset' parameter with the 'loads'
3137command.
wdenkc6097192002-11-03 00:24:07 +00003138
wdenk2729af92004-05-03 20:45:30 +00003139Example: install the image to address 0x40100000 (which on the
3140TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00003141
wdenk2729af92004-05-03 20:45:30 +00003142 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00003143
wdenk2729af92004-05-03 20:45:30 +00003144 .......... done
3145 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00003146
wdenk2729af92004-05-03 20:45:30 +00003147 => loads 40100000
3148 ## Ready for S-Record download ...
3149 ~>examples/image.srec
3150 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3151 ...
3152 15989 15990 15991 15992
3153 [file transfer complete]
3154 [connected]
3155 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003156
3157
wdenk2729af92004-05-03 20:45:30 +00003158You can check the success of the download using the 'iminfo' command;
Wolfgang Denk218ca722008-03-26 10:40:12 +01003159this includes a checksum verification so you can be sure no data
wdenk2729af92004-05-03 20:45:30 +00003160corruption happened:
wdenkc6097192002-11-03 00:24:07 +00003161
wdenk2729af92004-05-03 20:45:30 +00003162 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00003163
wdenk2729af92004-05-03 20:45:30 +00003164 ## Checking Image at 40100000 ...
3165 Image Name: 2.2.13 for initrd on TQM850L
3166 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3167 Data Size: 335725 Bytes = 327 kB = 0 MB
3168 Load Address: 00000000
3169 Entry Point: 0000000c
3170 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00003171
3172
wdenk2729af92004-05-03 20:45:30 +00003173Boot Linux:
3174-----------
wdenkc6097192002-11-03 00:24:07 +00003175
wdenk2729af92004-05-03 20:45:30 +00003176The "bootm" command is used to boot an application that is stored in
3177memory (RAM or Flash). In case of a Linux kernel image, the contents
3178of the "bootargs" environment variable is passed to the kernel as
3179parameters. You can check and modify this variable using the
3180"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00003181
3182
wdenk2729af92004-05-03 20:45:30 +00003183 => printenv bootargs
3184 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00003185
wdenk2729af92004-05-03 20:45:30 +00003186 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
wdenkc6097192002-11-03 00:24:07 +00003187
wdenk2729af92004-05-03 20:45:30 +00003188 => printenv bootargs
3189 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
wdenkc6097192002-11-03 00:24:07 +00003190
wdenk2729af92004-05-03 20:45:30 +00003191 => bootm 40020000
3192 ## Booting Linux kernel at 40020000 ...
3193 Image Name: 2.2.13 for NFS on TQM850L
3194 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3195 Data Size: 381681 Bytes = 372 kB = 0 MB
3196 Load Address: 00000000
3197 Entry Point: 0000000c
3198 Verifying Checksum ... OK
3199 Uncompressing Kernel Image ... OK
3200 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
3201 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3202 time_init: decrementer frequency = 187500000/60
3203 Calibrating delay loop... 49.77 BogoMIPS
3204 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3205 ...
wdenkc6097192002-11-03 00:24:07 +00003206
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003207If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk2729af92004-05-03 20:45:30 +00003208the memory addresses of both the kernel and the initrd image (PPBCOOT
3209format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00003210
wdenk2729af92004-05-03 20:45:30 +00003211 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00003212
wdenk2729af92004-05-03 20:45:30 +00003213 ## Checking Image at 40100000 ...
3214 Image Name: 2.2.13 for initrd on TQM850L
3215 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3216 Data Size: 335725 Bytes = 327 kB = 0 MB
3217 Load Address: 00000000
3218 Entry Point: 0000000c
3219 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00003220
wdenk2729af92004-05-03 20:45:30 +00003221 ## Checking Image at 40200000 ...
3222 Image Name: Simple Ramdisk Image
3223 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3224 Data Size: 566530 Bytes = 553 kB = 0 MB
3225 Load Address: 00000000
3226 Entry Point: 00000000
3227 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00003228
wdenk2729af92004-05-03 20:45:30 +00003229 => bootm 40100000 40200000
3230 ## Booting Linux kernel at 40100000 ...
3231 Image Name: 2.2.13 for initrd on TQM850L
3232 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3233 Data Size: 335725 Bytes = 327 kB = 0 MB
3234 Load Address: 00000000
3235 Entry Point: 0000000c
3236 Verifying Checksum ... OK
3237 Uncompressing Kernel Image ... OK
3238 ## Loading RAMDisk Image at 40200000 ...
3239 Image Name: Simple Ramdisk Image
3240 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3241 Data Size: 566530 Bytes = 553 kB = 0 MB
3242 Load Address: 00000000
3243 Entry Point: 00000000
3244 Verifying Checksum ... OK
3245 Loading Ramdisk ... OK
3246 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
3247 Boot arguments: root=/dev/ram
3248 time_init: decrementer frequency = 187500000/60
3249 Calibrating delay loop... 49.77 BogoMIPS
3250 ...
3251 RAMDISK: Compressed image found at block 0
3252 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00003253
wdenk2729af92004-05-03 20:45:30 +00003254 bash#
wdenkc6097192002-11-03 00:24:07 +00003255
Matthew McClintock02677682006-06-28 10:41:37 -05003256Boot Linux and pass a flat device tree:
3257-----------
3258
3259First, U-Boot must be compiled with the appropriate defines. See the section
3260titled "Linux Kernel Interface" above for a more in depth explanation. The
3261following is an example of how to start a kernel and pass an updated
3262flat device tree:
3263
3264=> print oftaddr
3265oftaddr=0x300000
3266=> print oft
3267oft=oftrees/mpc8540ads.dtb
3268=> tftp $oftaddr $oft
3269Speed: 1000, full duplex
3270Using TSEC0 device
3271TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3272Filename 'oftrees/mpc8540ads.dtb'.
3273Load address: 0x300000
3274Loading: #
3275done
3276Bytes transferred = 4106 (100a hex)
3277=> tftp $loadaddr $bootfile
3278Speed: 1000, full duplex
3279Using TSEC0 device
3280TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3281Filename 'uImage'.
3282Load address: 0x200000
3283Loading:############
3284done
3285Bytes transferred = 1029407 (fb51f hex)
3286=> print loadaddr
3287loadaddr=200000
3288=> print oftaddr
3289oftaddr=0x300000
3290=> bootm $loadaddr - $oftaddr
3291## Booting image at 00200000 ...
Wolfgang Denka9398e02006-11-27 15:32:42 +01003292 Image Name: Linux-2.6.17-dirty
3293 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3294 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintock02677682006-06-28 10:41:37 -05003295 Load Address: 00000000
Wolfgang Denka9398e02006-11-27 15:32:42 +01003296 Entry Point: 00000000
Matthew McClintock02677682006-06-28 10:41:37 -05003297 Verifying Checksum ... OK
3298 Uncompressing Kernel Image ... OK
3299Booting using flat device tree at 0x300000
3300Using MPC85xx ADS machine description
3301Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3302[snip]
3303
3304
wdenk2729af92004-05-03 20:45:30 +00003305More About U-Boot Image Types:
3306------------------------------
wdenk6069ff22003-02-28 00:49:47 +00003307
wdenk2729af92004-05-03 20:45:30 +00003308U-Boot supports the following image types:
wdenk6069ff22003-02-28 00:49:47 +00003309
wdenk2729af92004-05-03 20:45:30 +00003310 "Standalone Programs" are directly runnable in the environment
3311 provided by U-Boot; it is expected that (if they behave
3312 well) you can continue to work in U-Boot after return from
3313 the Standalone Program.
3314 "OS Kernel Images" are usually images of some Embedded OS which
3315 will take over control completely. Usually these programs
3316 will install their own set of exception handlers, device
3317 drivers, set up the MMU, etc. - this means, that you cannot
3318 expect to re-enter U-Boot except by resetting the CPU.
3319 "RAMDisk Images" are more or less just data blocks, and their
3320 parameters (address, size) are passed to an OS kernel that is
3321 being started.
3322 "Multi-File Images" contain several images, typically an OS
3323 (Linux) kernel image and one or more data images like
3324 RAMDisks. This construct is useful for instance when you want
3325 to boot over the network using BOOTP etc., where the boot
3326 server provides just a single image file, but you want to get
3327 for instance an OS kernel and a RAMDisk image.
stroesec1551ea2003-04-04 15:53:41 +00003328
wdenk2729af92004-05-03 20:45:30 +00003329 "Multi-File Images" start with a list of image sizes, each
3330 image size (in bytes) specified by an "uint32_t" in network
3331 byte order. This list is terminated by an "(uint32_t)0".
3332 Immediately after the terminating 0 follow the images, one by
3333 one, all aligned on "uint32_t" boundaries (size rounded up to
3334 a multiple of 4 bytes).
stroesec1551ea2003-04-04 15:53:41 +00003335
wdenk2729af92004-05-03 20:45:30 +00003336 "Firmware Images" are binary images containing firmware (like
3337 U-Boot or FPGA images) which usually will be programmed to
3338 flash memory.
stroesec1551ea2003-04-04 15:53:41 +00003339
wdenk2729af92004-05-03 20:45:30 +00003340 "Script files" are command sequences that will be executed by
3341 U-Boot's command interpreter; this feature is especially
3342 useful when you configure U-Boot to use a real shell (hush)
3343 as command interpreter.
wdenk6069ff22003-02-28 00:49:47 +00003344
Marek Vasut44f074c2012-03-14 21:52:45 +00003345Booting the Linux zImage:
3346-------------------------
3347
3348On some platforms, it's possible to boot Linux zImage. This is done
3349using the "bootz" command. The syntax of "bootz" command is the same
3350as the syntax of "bootm" command.
3351
Tom Rini8ac28562013-05-16 11:40:11 -04003352Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut017e1f32012-03-18 11:47:58 +00003353kernel with raw initrd images. The syntax is slightly different, the
3354address of the initrd must be augmented by it's size, in the following
3355format: "<initrd addres>:<initrd size>".
3356
wdenkc6097192002-11-03 00:24:07 +00003357
wdenk2729af92004-05-03 20:45:30 +00003358Standalone HOWTO:
3359=================
wdenkc6097192002-11-03 00:24:07 +00003360
wdenk2729af92004-05-03 20:45:30 +00003361One of the features of U-Boot is that you can dynamically load and
3362run "standalone" applications, which can use some resources of
3363U-Boot like console I/O functions or interrupt services.
wdenkc6097192002-11-03 00:24:07 +00003364
wdenk2729af92004-05-03 20:45:30 +00003365Two simple examples are included with the sources:
wdenkc6097192002-11-03 00:24:07 +00003366
wdenk2729af92004-05-03 20:45:30 +00003367"Hello World" Demo:
3368-------------------
wdenkc6097192002-11-03 00:24:07 +00003369
wdenk2729af92004-05-03 20:45:30 +00003370'examples/hello_world.c' contains a small "Hello World" Demo
3371application; it is automatically compiled when you build U-Boot.
3372It's configured to run at address 0x00040004, so you can play with it
3373like that:
wdenkc6097192002-11-03 00:24:07 +00003374
wdenk2729af92004-05-03 20:45:30 +00003375 => loads
3376 ## Ready for S-Record download ...
3377 ~>examples/hello_world.srec
3378 1 2 3 4 5 6 7 8 9 10 11 ...
3379 [file transfer complete]
3380 [connected]
3381 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00003382
wdenk2729af92004-05-03 20:45:30 +00003383 => go 40004 Hello World! This is a test.
3384 ## Starting application at 0x00040004 ...
3385 Hello World
3386 argc = 7
3387 argv[0] = "40004"
3388 argv[1] = "Hello"
3389 argv[2] = "World!"
3390 argv[3] = "This"
3391 argv[4] = "is"
3392 argv[5] = "a"
3393 argv[6] = "test."
3394 argv[7] = "<NULL>"
3395 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00003396
wdenk2729af92004-05-03 20:45:30 +00003397 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00003398
wdenk2729af92004-05-03 20:45:30 +00003399Another example, which demonstrates how to register a CPM interrupt
3400handler with the U-Boot code, can be found in 'examples/timer.c'.
3401Here, a CPM timer is set up to generate an interrupt every second.
3402The interrupt service routine is trivial, just printing a '.'
3403character, but this is just a demo program. The application can be
3404controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00003405
wdenk2729af92004-05-03 20:45:30 +00003406 ? - print current values og the CPM Timer registers
3407 b - enable interrupts and start timer
3408 e - stop timer and disable interrupts
3409 q - quit application
wdenkc6097192002-11-03 00:24:07 +00003410
wdenk2729af92004-05-03 20:45:30 +00003411 => loads
3412 ## Ready for S-Record download ...
3413 ~>examples/timer.srec
3414 1 2 3 4 5 6 7 8 9 10 11 ...
3415 [file transfer complete]
3416 [connected]
3417 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00003418
wdenk2729af92004-05-03 20:45:30 +00003419 => go 40004
3420 ## Starting application at 0x00040004 ...
3421 TIMERS=0xfff00980
3422 Using timer 1
3423 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00003424
wdenk2729af92004-05-03 20:45:30 +00003425Hit 'b':
3426 [q, b, e, ?] Set interval 1000000 us
3427 Enabling timer
3428Hit '?':
3429 [q, b, e, ?] ........
3430 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3431Hit '?':
3432 [q, b, e, ?] .
3433 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3434Hit '?':
3435 [q, b, e, ?] .
3436 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3437Hit '?':
3438 [q, b, e, ?] .
3439 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3440Hit 'e':
3441 [q, b, e, ?] ...Stopping timer
3442Hit 'q':
3443 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00003444
3445
wdenk2729af92004-05-03 20:45:30 +00003446Minicom warning:
3447================
wdenk85ec0bc2003-03-31 16:34:49 +00003448
wdenk2729af92004-05-03 20:45:30 +00003449Over time, many people have reported problems when trying to use the
3450"minicom" terminal emulation program for serial download. I (wd)
3451consider minicom to be broken, and recommend not to use it. Under
3452Unix, I recommend to use C-Kermit for general purpose use (and
3453especially for kermit binary protocol download ("loadb" command), and
Karl O. Pince53515a2012-10-01 05:11:56 +00003454use "cu" for S-Record download ("loads" command). See
Naoki Hayama047f6ec2020-10-08 13:17:16 +09003455https://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
Karl O. Pince53515a2012-10-01 05:11:56 +00003456for help with kermit.
3457
wdenk85ec0bc2003-03-31 16:34:49 +00003458
wdenk2729af92004-05-03 20:45:30 +00003459Nevertheless, if you absolutely want to use it try adding this
3460configuration to your "File transfer protocols" section:
wdenk52f52c12003-06-19 23:04:19 +00003461
wdenk2729af92004-05-03 20:45:30 +00003462 Name Program Name U/D FullScr IO-Red. Multi
3463 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3464 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk52f52c12003-06-19 23:04:19 +00003465
3466
wdenk2729af92004-05-03 20:45:30 +00003467NetBSD Notes:
3468=============
wdenkc6097192002-11-03 00:24:07 +00003469
wdenk2729af92004-05-03 20:45:30 +00003470Starting at version 0.9.2, U-Boot supports NetBSD both as host
3471(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenkc6097192002-11-03 00:24:07 +00003472
wdenk2729af92004-05-03 20:45:30 +00003473Building requires a cross environment; it is known to work on
3474NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3475need gmake since the Makefiles are not compatible with BSD make).
3476Note that the cross-powerpc package does not install include files;
3477attempting to build U-Boot will fail because <machine/ansi.h> is
3478missing. This file has to be installed and patched manually:
wdenkc6097192002-11-03 00:24:07 +00003479
wdenk2729af92004-05-03 20:45:30 +00003480 # cd /usr/pkg/cross/powerpc-netbsd/include
3481 # mkdir powerpc
3482 # ln -s powerpc machine
3483 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3484 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenkc6097192002-11-03 00:24:07 +00003485
wdenk2729af92004-05-03 20:45:30 +00003486Native builds *don't* work due to incompatibilities between native
3487and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00003488
wdenk2729af92004-05-03 20:45:30 +00003489Booting assumes that (the first part of) the image booted is a
3490stage-2 loader which in turn loads and then invokes the kernel
3491proper. Loader sources will eventually appear in the NetBSD source
3492tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenk2a8af182005-04-13 10:02:42 +00003493meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00003494
3495
wdenk2729af92004-05-03 20:45:30 +00003496Implementation Internals:
3497=========================
wdenkc6097192002-11-03 00:24:07 +00003498
wdenk2729af92004-05-03 20:45:30 +00003499The following is not intended to be a complete description of every
3500implementation detail. However, it should help to understand the
3501inner workings of U-Boot and make it easier to port it to custom
3502hardware.
wdenkc6097192002-11-03 00:24:07 +00003503
3504
wdenk2729af92004-05-03 20:45:30 +00003505Initial Stack, Global Data:
3506---------------------------
wdenkc6097192002-11-03 00:24:07 +00003507
wdenk2729af92004-05-03 20:45:30 +00003508The implementation of U-Boot is complicated by the fact that U-Boot
3509starts running out of ROM (flash memory), usually without access to
3510system RAM (because the memory controller is not initialized yet).
3511This means that we don't have writable Data or BSS segments, and BSS
3512is not initialized as zero. To be able to get a C environment working
3513at all, we have to allocate at least a minimal stack. Implementation
3514options for this are defined and restricted by the CPU used: Some CPU
3515models provide on-chip memory (like the IMMR area on MPC8xx and
3516MPC826x processors), on others (parts of) the data cache can be
3517locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00003518
Wolfgang Denk218ca722008-03-26 10:40:12 +01003519 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk06682362008-12-30 22:56:11 +01003520 U-Boot mailing list:
wdenk43d96162003-03-06 00:02:04 +00003521
wdenk2729af92004-05-03 20:45:30 +00003522 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3523 From: "Chris Hallinan" <clh@net1plus.com>
3524 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3525 ...
wdenk43d96162003-03-06 00:02:04 +00003526
wdenk2729af92004-05-03 20:45:30 +00003527 Correct me if I'm wrong, folks, but the way I understand it
3528 is this: Using DCACHE as initial RAM for Stack, etc, does not
3529 require any physical RAM backing up the cache. The cleverness
3530 is that the cache is being used as a temporary supply of
3531 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003532 beyond the scope of this list to explain the details, but you
wdenk2729af92004-05-03 20:45:30 +00003533 can see how this works by studying the cache architecture and
3534 operation in the architecture and processor-specific manuals.
wdenk43d96162003-03-06 00:02:04 +00003535
wdenk2729af92004-05-03 20:45:30 +00003536 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3537 is another option for the system designer to use as an
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003538 initial stack/RAM area prior to SDRAM being available. Either
wdenk2729af92004-05-03 20:45:30 +00003539 option should work for you. Using CS 4 should be fine if your
3540 board designers haven't used it for something that would
3541 cause you grief during the initial boot! It is frequently not
3542 used.
wdenk43d96162003-03-06 00:02:04 +00003543
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003544 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk2729af92004-05-03 20:45:30 +00003545 with your processor/board/system design. The default value
3546 you will find in any recent u-boot distribution in
Stefan Roese8a316c92005-08-01 16:49:12 +02003547 walnut.h should work for you. I'd set it to a value larger
wdenk2729af92004-05-03 20:45:30 +00003548 than your SDRAM module. If you have a 64MB SDRAM module, set
3549 it above 400_0000. Just make sure your board has no resources
3550 that are supposed to respond to that address! That code in
3551 start.S has been around a while and should work as is when
3552 you get the config right.
wdenk43d96162003-03-06 00:02:04 +00003553
wdenk2729af92004-05-03 20:45:30 +00003554 -Chris Hallinan
3555 DS4.COM, Inc.
wdenk43d96162003-03-06 00:02:04 +00003556
wdenk2729af92004-05-03 20:45:30 +00003557It is essential to remember this, since it has some impact on the C
3558code for the initialization procedures:
wdenkc6097192002-11-03 00:24:07 +00003559
wdenk2729af92004-05-03 20:45:30 +00003560* Initialized global data (data segment) is read-only. Do not attempt
3561 to write it.
wdenkc6097192002-11-03 00:24:07 +00003562
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003563* Do not use any uninitialized global data (or implicitly initialized
wdenk2729af92004-05-03 20:45:30 +00003564 as zero data - BSS segment) at all - this is undefined, initiali-
3565 zation is performed later (when relocating to RAM).
wdenkc6097192002-11-03 00:24:07 +00003566
wdenk2729af92004-05-03 20:45:30 +00003567* Stack space is very limited. Avoid big data buffers or things like
3568 that.
wdenkc6097192002-11-03 00:24:07 +00003569
wdenk2729af92004-05-03 20:45:30 +00003570Having only the stack as writable memory limits means we cannot use
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003571normal global data to share information between the code. But it
wdenk2729af92004-05-03 20:45:30 +00003572turned out that the implementation of U-Boot can be greatly
3573simplified by making a global data structure (gd_t) available to all
3574functions. We could pass a pointer to this data as argument to _all_
3575functions, but this would bloat the code. Instead we use a feature of
3576the GCC compiler (Global Register Variables) to share the data: we
3577place a pointer (gd) to the global data into a register which we
3578reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00003579
wdenk2729af92004-05-03 20:45:30 +00003580When choosing a register for such a purpose we are restricted by the
3581relevant (E)ABI specifications for the current architecture, and by
3582GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00003583
wdenk2729af92004-05-03 20:45:30 +00003584For PowerPC, the following registers have specific use:
3585 R1: stack pointer
Wolfgang Denke7670f62008-02-14 22:43:22 +01003586 R2: reserved for system use
wdenk2729af92004-05-03 20:45:30 +00003587 R3-R4: parameter passing and return values
3588 R5-R10: parameter passing
3589 R13: small data area pointer
3590 R30: GOT pointer
3591 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00003592
Joakim Tjernlunde6bee802010-01-19 14:41:58 +01003593 (U-Boot also uses R12 as internal GOT pointer. r12
3594 is a volatile register so r12 needs to be reset when
3595 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00003596
Wolfgang Denke7670f62008-02-14 22:43:22 +01003597 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00003598
wdenk2729af92004-05-03 20:45:30 +00003599 Note: on PPC, we could use a static initializer (since the
3600 address of the global data structure is known at compile time),
3601 but it turned out that reserving a register results in somewhat
3602 smaller code - although the code savings are not that big (on
3603 average for all boards 752 bytes for the whole U-Boot image,
3604 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00003605
wdenk2729af92004-05-03 20:45:30 +00003606On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00003607
wdenk2729af92004-05-03 20:45:30 +00003608 R0: function argument word/integer result
3609 R1-R3: function argument word
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02003610 R9: platform specific
3611 R10: stack limit (used only if stack checking is enabled)
wdenk2729af92004-05-03 20:45:30 +00003612 R11: argument (frame) pointer
3613 R12: temporary workspace
3614 R13: stack pointer
3615 R14: link register
3616 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00003617
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02003618 ==> U-Boot will use R9 to hold a pointer to the global data
3619
3620 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00003621
Thomas Chou0df01fd2010-05-21 11:08:03 +08003622On Nios II, the ABI is documented here:
Naoki Hayama047f6ec2020-10-08 13:17:16 +09003623 https://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
Thomas Chou0df01fd2010-05-21 11:08:03 +08003624
3625 ==> U-Boot will use gp to hold a pointer to the global data
3626
3627 Note: on Nios II, we give "-G0" option to gcc and don't use gp
3628 to access small data sections, so gp is free.
3629
Macpaul Linafc1ce82011-10-19 20:41:11 +00003630On NDS32, the following registers are used:
3631
3632 R0-R1: argument/return
3633 R2-R5: argument
3634 R15: temporary register for assembler
3635 R16: trampoline register
3636 R28: frame pointer (FP)
3637 R29: global pointer (GP)
3638 R30: link register (LP)
3639 R31: stack pointer (SP)
3640 PC: program counter (PC)
3641
3642 ==> U-Boot will use R10 to hold a pointer to the global data
3643
Wolfgang Denkd87080b2006-03-31 18:32:53 +02003644NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
3645or current versions of GCC may "optimize" the code too much.
wdenkc6097192002-11-03 00:24:07 +00003646
Rick Chen3fafced2017-12-26 13:55:59 +08003647On RISC-V, the following registers are used:
3648
3649 x0: hard-wired zero (zero)
3650 x1: return address (ra)
3651 x2: stack pointer (sp)
3652 x3: global pointer (gp)
3653 x4: thread pointer (tp)
3654 x5: link register (t0)
3655 x8: frame pointer (fp)
3656 x10-x11: arguments/return values (a0-1)
3657 x12-x17: arguments (a2-7)
3658 x28-31: temporaries (t3-6)
3659 pc: program counter (pc)
3660
3661 ==> U-Boot will use gp to hold a pointer to the global data
3662
wdenk2729af92004-05-03 20:45:30 +00003663Memory Management:
3664------------------
wdenkc6097192002-11-03 00:24:07 +00003665
wdenk2729af92004-05-03 20:45:30 +00003666U-Boot runs in system state and uses physical addresses, i.e. the
3667MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00003668
wdenk2729af92004-05-03 20:45:30 +00003669The available memory is mapped to fixed addresses using the memory
3670controller. In this process, a contiguous block is formed for each
3671memory type (Flash, SDRAM, SRAM), even when it consists of several
3672physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00003673
wdenk2729af92004-05-03 20:45:30 +00003674U-Boot is installed in the first 128 kB of the first Flash bank (on
3675TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3676booting and sizing and initializing DRAM, the code relocates itself
3677to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003678memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk2729af92004-05-03 20:45:30 +00003679configuration setting]. Below that, a structure with global Board
3680Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00003681
wdenk2729af92004-05-03 20:45:30 +00003682Additionally, some exception handler code is copied to the low 8 kB
3683of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00003684
wdenk2729af92004-05-03 20:45:30 +00003685So a typical memory configuration with 16 MB of DRAM could look like
3686this:
wdenkc6097192002-11-03 00:24:07 +00003687
wdenk2729af92004-05-03 20:45:30 +00003688 0x0000 0000 Exception Vector code
3689 :
3690 0x0000 1FFF
3691 0x0000 2000 Free for Application Use
3692 :
3693 :
wdenkc6097192002-11-03 00:24:07 +00003694
wdenk2729af92004-05-03 20:45:30 +00003695 :
3696 :
3697 0x00FB FF20 Monitor Stack (Growing downward)
3698 0x00FB FFAC Board Info Data and permanent copy of global data
3699 0x00FC 0000 Malloc Arena
3700 :
3701 0x00FD FFFF
3702 0x00FE 0000 RAM Copy of Monitor Code
3703 ... eventually: LCD or video framebuffer
3704 ... eventually: pRAM (Protected RAM - unchanged by reset)
3705 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00003706
3707
wdenk2729af92004-05-03 20:45:30 +00003708System Initialization:
3709----------------------
wdenkc6097192002-11-03 00:24:07 +00003710
wdenk2729af92004-05-03 20:45:30 +00003711In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003712(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003713configuration for CS0# this is a mirror of the on board Flash memory.
wdenk2729af92004-05-03 20:45:30 +00003714To be able to re-map memory U-Boot then jumps to its link address.
3715To be able to implement the initialization code in C, a (small!)
3716initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02003717which provide such a feature like), or in a locked part of the data
3718cache. After that, U-Boot initializes the CPU core, the caches and
3719the SIU.
wdenkc6097192002-11-03 00:24:07 +00003720
wdenk2729af92004-05-03 20:45:30 +00003721Next, all (potentially) available memory banks are mapped using a
3722preliminary mapping. For example, we put them on 512 MB boundaries
3723(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3724on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3725programmed for SDRAM access. Using the temporary configuration, a
3726simple memory test is run that determines the size of the SDRAM
3727banks.
wdenkc6097192002-11-03 00:24:07 +00003728
wdenk2729af92004-05-03 20:45:30 +00003729When there is more than one SDRAM bank, and the banks are of
3730different size, the largest is mapped first. For equal size, the first
3731bank (CS2#) is mapped first. The first mapping is always for address
37320x00000000, with any additional banks following immediately to create
3733contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00003734
wdenk2729af92004-05-03 20:45:30 +00003735Then, the monitor installs itself at the upper end of the SDRAM area
3736and allocates memory for use by malloc() and for the global Board
3737Info data; also, the exception vector code is copied to the low RAM
3738pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00003739
wdenk2729af92004-05-03 20:45:30 +00003740Only after this relocation will you have a "normal" C environment;
3741until that you are restricted in several ways, mostly because you are
3742running from ROM, and because the code will have to be relocated to a
3743new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00003744
3745
wdenk2729af92004-05-03 20:45:30 +00003746U-Boot Porting Guide:
3747----------------------
wdenkc6097192002-11-03 00:24:07 +00003748
wdenk2729af92004-05-03 20:45:30 +00003749[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3750list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00003751
3752
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003753int main(int argc, char *argv[])
wdenk2729af92004-05-03 20:45:30 +00003754{
3755 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00003756
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003757 signal(SIGALRM, no_more_time);
3758 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00003759
wdenk2729af92004-05-03 20:45:30 +00003760 if (available_money > available_manpower) {
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003761 Pay consultant to port U-Boot;
wdenkc6097192002-11-03 00:24:07 +00003762 return 0;
3763 }
3764
wdenk2729af92004-05-03 20:45:30 +00003765 Download latest U-Boot source;
3766
Wolfgang Denk06682362008-12-30 22:56:11 +01003767 Subscribe to u-boot mailing list;
wdenk2729af92004-05-03 20:45:30 +00003768
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003769 if (clueless)
3770 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00003771
wdenk2729af92004-05-03 20:45:30 +00003772 while (learning) {
3773 Read the README file in the top level directory;
Naoki Hayama047f6ec2020-10-08 13:17:16 +09003774 Read https://www.denx.de/wiki/bin/view/DULG/Manual;
Patrick Delaunay24bcaec2020-02-28 15:18:10 +01003775 Read applicable doc/README.*;
wdenk2729af92004-05-03 20:45:30 +00003776 Read the source, Luke;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003777 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk2729af92004-05-03 20:45:30 +00003778 }
wdenkc6097192002-11-03 00:24:07 +00003779
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003780 if (available_money > toLocalCurrency ($2500))
3781 Buy a BDI3000;
3782 else
wdenk2729af92004-05-03 20:45:30 +00003783 Add a lot of aggravation and time;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003784
3785 if (a similar board exists) { /* hopefully... */
3786 cp -a board/<similar> board/<myboard>
3787 cp include/configs/<similar>.h include/configs/<myboard>.h
3788 } else {
3789 Create your own board support subdirectory;
3790 Create your own board include/configs/<myboard>.h file;
wdenk2729af92004-05-03 20:45:30 +00003791 }
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003792 Edit new board/<myboard> files
3793 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00003794
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04003795 while (!accepted) {
3796 while (!running) {
3797 do {
3798 Add / modify source code;
3799 } until (compiles);
3800 Debug;
3801 if (clueless)
3802 email("Hi, I am having problems...");
3803 }
3804 Send patch file to the U-Boot email list;
3805 if (reasonable critiques)
3806 Incorporate improvements from email list code review;
3807 else
3808 Defend code as written;
wdenk2729af92004-05-03 20:45:30 +00003809 }
wdenkc6097192002-11-03 00:24:07 +00003810
wdenk2729af92004-05-03 20:45:30 +00003811 return 0;
3812}
3813
3814void no_more_time (int sig)
3815{
3816 hire_a_guru();
3817}
wdenkc6097192002-11-03 00:24:07 +00003818
3819
wdenk2729af92004-05-03 20:45:30 +00003820Coding Standards:
3821-----------------
wdenkc6097192002-11-03 00:24:07 +00003822
wdenk2729af92004-05-03 20:45:30 +00003823All contributions to U-Boot should conform to the Linux kernel
Baruch Siach659208d2017-12-10 17:34:35 +02003824coding style; see the kernel coding style guide at
3825https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
3826script "scripts/Lindent" in your Linux kernel source directory.
wdenk2729af92004-05-03 20:45:30 +00003827
Detlev Zundel2c051652006-09-01 15:39:02 +02003828Source files originating from a different project (for example the
3829MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003830reformatted to ease subsequent migration to newer versions of those
Detlev Zundel2c051652006-09-01 15:39:02 +02003831sources.
3832
3833Please note that U-Boot is implemented in C (and to some small parts in
3834Assembler); no C++ is used, so please do not use C++ style comments (//)
3835in your code.
wdenk2729af92004-05-03 20:45:30 +00003836
3837Please also stick to the following formatting rules:
3838- remove any trailing white space
Wolfgang Denk7ca92962011-07-27 10:59:55 +00003839- use TAB characters for indentation and vertical alignment, not spaces
wdenk2729af92004-05-03 20:45:30 +00003840- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk7ca92962011-07-27 10:59:55 +00003841- do not add more than 2 consecutive empty lines to source files
wdenk2729af92004-05-03 20:45:30 +00003842- do not add trailing empty lines to source files
3843
3844Submissions which do not conform to the standards may be returned
3845with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00003846
3847
wdenk2729af92004-05-03 20:45:30 +00003848Submitting Patches:
3849-------------------
wdenkc6097192002-11-03 00:24:07 +00003850
wdenk2729af92004-05-03 20:45:30 +00003851Since the number of patches for U-Boot is growing, we need to
3852establish some rules. Submissions which do not conform to these rules
3853may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00003854
Naoki Hayama047f6ec2020-10-08 13:17:16 +09003855Please see https://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denk218ca722008-03-26 10:40:12 +01003856
Wolfgang Denk06682362008-12-30 22:56:11 +01003857Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childs1dade182017-11-14 22:56:42 -08003858see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk06682362008-12-30 22:56:11 +01003859
wdenk2729af92004-05-03 20:45:30 +00003860When you send a patch, please include the following information with
3861it:
wdenkc6097192002-11-03 00:24:07 +00003862
wdenk2729af92004-05-03 20:45:30 +00003863* For bug fixes: a description of the bug and how your patch fixes
3864 this bug. Please try to include a way of demonstrating that the
3865 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00003866
wdenk2729af92004-05-03 20:45:30 +00003867* For new features: a description of the feature and your
3868 implementation.
wdenkc6097192002-11-03 00:24:07 +00003869
Robert P. J. Day7207b362015-12-19 07:16:10 -05003870* For major contributions, add a MAINTAINERS file with your
3871 information and associated file and directory references.
wdenk2729af92004-05-03 20:45:30 +00003872
Albert ARIBAUD27af9302013-09-11 15:52:51 +02003873* When you add support for a new board, don't forget to add a
3874 maintainer e-mail address to the boards.cfg file, too.
wdenk2729af92004-05-03 20:45:30 +00003875
3876* If your patch adds new configuration options, don't forget to
3877 document these in the README file.
3878
Wolfgang Denk218ca722008-03-26 10:40:12 +01003879* The patch itself. If you are using git (which is *strongly*
3880 recommended) you can easily generate the patch using the
Wolfgang Denk7ca92962011-07-27 10:59:55 +00003881 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denk218ca722008-03-26 10:40:12 +01003882 the U-Boot mailing list, you will avoid most of the common problems
3883 with some other mail clients.
wdenk2729af92004-05-03 20:45:30 +00003884
Wolfgang Denk218ca722008-03-26 10:40:12 +01003885 If you cannot use git, use "diff -purN OLD NEW". If your version of
3886 diff does not support these options, then get the latest version of
3887 GNU diff.
wdenk2729af92004-05-03 20:45:30 +00003888
Wolfgang Denk218ca722008-03-26 10:40:12 +01003889 The current directory when running this command shall be the parent
3890 directory of the U-Boot source tree (i. e. please make sure that
3891 your patch includes sufficient directory information for the
3892 affected files).
3893
3894 We prefer patches as plain text. MIME attachments are discouraged,
3895 and compressed attachments must not be used.
wdenk2729af92004-05-03 20:45:30 +00003896
3897* If one logical set of modifications affects or creates several
3898 files, all these changes shall be submitted in a SINGLE patch file.
3899
3900* Changesets that contain different, unrelated modifications shall be
3901 submitted as SEPARATE patches, one patch per changeset.
3902
3903
3904Notes:
3905
Simon Glass6de80f22016-07-27 20:33:08 -06003906* Before sending the patch, run the buildman script on your patched
wdenk2729af92004-05-03 20:45:30 +00003907 source tree and make sure that no errors or warnings are reported
3908 for any of the boards.
3909
3910* Keep your modifications to the necessary minimum: A patch
3911 containing several unrelated changes or arbitrary reformats will be
3912 returned with a request to re-formatting / split it.
3913
3914* If you modify existing code, make sure that your new code does not
3915 add to the memory footprint of the code ;-) Small is beautiful!
3916 When adding new features, these should compile conditionally only
3917 (using #ifdef), and the resulting code with the new feature
3918 disabled must not need more memory than the old code without your
3919 modification.
wdenk90dc6702005-05-03 14:12:25 +00003920
Wolfgang Denk06682362008-12-30 22:56:11 +01003921* Remember that there is a size limit of 100 kB per message on the
3922 u-boot mailing list. Bigger patches will be moderated. If they are
3923 reasonable and not too big, they will be acknowledged. But patches
3924 bigger than the size limit should be avoided.