blob: f26c34a5e200b16f486b6e03e4909ccf7ab976a1 [file] [log] [blame]
Tom Rini10e47792018-05-06 17:58:06 -04001# SPDX-License-Identifier: GPL-2.0+
wdenkc6097192002-11-03 00:24:07 +00002#
Wolfgang Denk1234ce72013-06-21 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
wdenkce4832c2004-10-17 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
Heinrich Schuchardtbdabeb82023-01-25 19:14:59 +010031In general, all boards for which a default configuration file exists in the
32configs/ directory 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
Heinrich Schuchardtbdabeb82023-01-25 19:14:59 +010035In case of problems you can use
wdenkc6097192002-11-03 00:24:07 +000036
Heinrich Schuchardtbdabeb82023-01-25 19:14:59 +010037 scripts/get_maintainer.pl <path>
Robert P. J. Day974ed2f2012-11-14 02:03:20 +000038
Heinrich Schuchardtbdabeb82023-01-25 19:14:59 +010039to identify the people or companies responsible for various boards and
40subsystems. Or have a look at the git log.
Robert P. J. Day974ed2f2012-11-14 02:03:20 +000041
wdenkc6097192002-11-03 00:24:07 +000042
43Where to get help:
44==================
45
wdenk24ee89b2002-11-03 17:56:27 +000046In case you have questions about, problems with or contributions for
Robert P. J. Day076ed9b2015-12-19 07:16:10 -050047U-Boot, you should send a message to the U-Boot mailing list at
Peter Tyser8804a612008-09-10 09:18:34 -050048<u-boot@lists.denx.de>. There is also an archive of previous traffic
49on the mailing list - please search the archive before asking FAQ's.
Naoki Hayama2bc50c22020-10-08 13:16:18 +090050Please see https://lists.denx.de/pipermail/u-boot and
51https://marc.info/?l=u-boot
wdenkc6097192002-11-03 00:24:07 +000052
Wolfgang Denkb240aef2008-03-26 10:40:12 +010053Where to get source code:
54=========================
55
Robert P. J. Day076ed9b2015-12-19 07:16:10 -050056The U-Boot source code is maintained in the Git repository at
Heinrich Schuchardt28b2b852021-02-24 13:19:04 +010057https://source.denx.de/u-boot/u-boot.git ; you can browse it online at
58https://source.denx.de/u-boot/u-boot
Wolfgang Denkb240aef2008-03-26 10:40:12 +010059
Naoki Hayama65ae68a2020-10-08 13:16:25 +090060The "Tags" links on this page allow you to download tarballs of
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +020061any version you might be interested in. Official releases are also
Naoki Hayama65ae68a2020-10-08 13:16:25 +090062available from the DENX file server through HTTPS or FTP.
63https://ftp.denx.de/pub/u-boot/
64ftp://ftp.denx.de/pub/u-boot/
Wolfgang Denkb240aef2008-03-26 10:40:12 +010065
66
wdenkc6097192002-11-03 00:24:07 +000067Where we come from:
68===================
69
70- start from 8xxrom sources
Naoki Hayamae0cc1852020-10-08 13:17:16 +090071- create PPCBoot project (https://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000072- clean up code
73- make it easier to add custom boards
74- make it possible to add other [PowerPC] CPUs
75- extend functions, especially:
76 * Provide extended interface to Linux boot loader
77 * S-Record download
78 * network boot
Simon Glassaaef3bf2019-08-01 09:47:14 -060079 * ATA disk / SCSI ... boot
Naoki Hayamae0cc1852020-10-08 13:17:16 +090080- create ARMBoot project (https://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000081- add other CPU families (starting with ARM)
Naoki Hayamae0cc1852020-10-08 13:17:16 +090082- create U-Boot project (https://sourceforge.net/projects/u-boot)
83- current project page: see https://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000084
85
86Names and Spelling:
87===================
88
89The "official" name of this project is "Das U-Boot". The spelling
90"U-Boot" shall be used in all written text (documentation, comments
91in source files etc.). Example:
92
93 This is the README file for the U-Boot project.
94
95File names etc. shall be based on the string "u-boot". Examples:
96
97 include/asm-ppc/u-boot.h
98
99 #include <asm/u-boot.h>
100
101Variable names, preprocessor constants etc. shall be either based on
102the string "u_boot" or on "U_BOOT". Example:
wdenkc6097192002-11-03 00:24:07 +0000103
wdenk24ee89b2002-11-03 17:56:27 +0000104 U_BOOT_VERSION u_boot_logo
105 IH_OS_U_BOOT u_boot_hush_start
106
wdenkc6097192002-11-03 00:24:07 +0000107
wdenkc6097192002-11-03 00:24:07 +0000108Software Configuration:
109=======================
110
wdenkc6097192002-11-03 00:24:07 +0000111Selection of Processor Architecture and Board Type:
112---------------------------------------------------
113
114For all supported boards there are ready-to-use default
Holger Freyther7ba4e572014-08-04 09:26:05 +0200115configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000116
117Example: For a TQM823L module type:
118
119 cd u-boot
Holger Freyther7ba4e572014-08-04 09:26:05 +0200120 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000121
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500122Note: If you're looking for the default configuration file for a board
123you're sure used to be there but is now missing, check the file
124doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000125
Simon Glass53552c92014-03-22 17:12:59 -0600126Sandbox Environment:
127--------------------
128
129U-Boot can be built natively to run on a Linux host using the 'sandbox'
130board. This allows feature development which is not board- or architecture-
131specific to be undertaken on a native platform. The sandbox is also used to
132run some of U-Boot's tests.
133
Heinrich Schuchardtfda020e2023-01-25 19:14:56 +0100134See doc/arch/sandbox/sandbox.rst for more details.
Simon Glass53552c92014-03-22 17:12:59 -0600135
136
Simon Glassd8711af2015-03-03 08:03:00 -0700137Board Initialisation Flow:
138--------------------------
139
140This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500141SPL and U-Boot proper (i.e. they both follow the same rules).
142
143Note: "SPL" stands for "Secondary Program Loader," which is explained in
144more detail later in this file.
145
146At present, SPL mostly uses a separate code path, but the function names
147and roles of each function are the same. Some boards or architectures
148may not conform to this. At least most ARM boards which use
149CONFIG_SPL_FRAMEWORK conform to this.
Simon Glassd8711af2015-03-03 08:03:00 -0700150
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500151Execution typically starts with an architecture-specific (and possibly
152CPU-specific) start.S file, such as:
153
154 - arch/arm/cpu/armv7/start.S
155 - arch/powerpc/cpu/mpc83xx/start.S
156 - arch/mips/cpu/start.S
157
158and so on. From there, three functions are called; the purpose and
159limitations of each of these functions are described below.
Simon Glassd8711af2015-03-03 08:03:00 -0700160
161lowlevel_init():
162 - purpose: essential init to permit execution to reach board_init_f()
163 - no global_data or BSS
164 - there is no stack (ARMv7 may have one but it will soon be removed)
165 - must not set up SDRAM or use console
166 - must only do the bare minimum to allow execution to continue to
167 board_init_f()
168 - this is almost never needed
169 - return normally from this function
170
171board_init_f():
172 - purpose: set up the machine ready for running board_init_r():
173 i.e. SDRAM and serial UART
174 - global_data is available
175 - stack is in SRAM
176 - BSS is not available, so you cannot use global/static variables,
177 only stack variables and global_data
178
179 Non-SPL-specific notes:
180 - dram_init() is called to set up DRAM. If already done in SPL this
181 can do nothing
182
183 SPL-specific notes:
184 - you can override the entire board_init_f() function with your own
185 version as needed.
186 - preloader_console_init() can be called here in extremis
187 - should set up SDRAM, and anything needed to make the UART work
Naoki Hayamaebfd8192020-09-24 15:57:19 +0900188 - there is no need to clear BSS, it will be done by crt0.S
Andreas Dannenberg7673bed2019-08-08 12:54:49 -0500189 - for specific scenarios on certain architectures an early BSS *can*
190 be made available (via CONFIG_SPL_EARLY_BSS by moving the clearing
191 of BSS prior to entering board_init_f()) but doing so is discouraged.
192 Instead it is strongly recommended to architect any code changes
193 or additions such to not depend on the availability of BSS during
194 board_init_f() as indicated in other sections of this README to
195 maintain compatibility and consistency across the entire code base.
Simon Glassd8711af2015-03-03 08:03:00 -0700196 - must return normally from this function (don't call board_init_r()
197 directly)
198
199Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
200this point the stack and global_data are relocated to below
201CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
202memory.
203
204board_init_r():
205 - purpose: main execution, common code
206 - global_data is available
207 - SDRAM is available
208 - BSS is available, all static/global variables can be used
209 - execution eventually continues to main_loop()
210
211 Non-SPL-specific notes:
212 - U-Boot is relocated to the top of memory and is now running from
213 there.
214
215 SPL-specific notes:
216 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
Ashish Kumar11234062017-08-11 11:09:14 +0530217 CONFIG_SYS_FSL_HAS_CCI400
218
219 Defined For SoC that has cache coherent interconnect
220 CCN-400
wdenk1272e232002-11-10 22:06:23 +0000221
Ashish Kumar97393d62017-08-18 10:54:36 +0530222 CONFIG_SYS_FSL_HAS_CCN504
223
224 Defined for SoC that has cache coherent interconnect CCN-504
225
wdenkc6097192002-11-03 00:24:07 +0000226The following options need to be configured:
227
Kim Phillips203fee32007-08-10 13:28:25 -0500228- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000229
Kim Phillips203fee32007-08-10 13:28:25 -0500230- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk994ad962006-10-24 14:42:37 +0200231
Kumar Galaf4fb90f2011-02-18 05:40:54 -0600232- 85xx CPU Options:
York Sun2394a0f2012-10-08 07:44:30 +0000233 CONFIG_SYS_PPC64
234
235 Specifies that the core is a 64-bit PowerPC implementation (implements
236 the "64" category of the Power ISA). This is necessary for ePAPR
237 compliance, among other possible reasons.
238
Scott Wood80806962012-08-14 10:14:53 +0000239 CONFIG_SYS_FSL_ERRATUM_A004510
240
241 Enables a workaround for erratum A004510. If set,
242 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
Tom Rini376b88a2022-10-28 20:27:13 -0400243 CFG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
Scott Wood80806962012-08-14 10:14:53 +0000244
245 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
246 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
247
248 Defines one or two SoC revisions (low 8 bits of SVR)
249 for which the A004510 workaround should be applied.
250
251 The rest of SVR is either not relevant to the decision
252 of whether the erratum is present (e.g. p2040 versus
253 p2041) or is implied by the build target, which controls
254 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
255
256 See Freescale App Note 4493 for more information about
257 this erratum.
258
Tom Rini376b88a2022-10-28 20:27:13 -0400259 CFG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
Scott Wood80806962012-08-14 10:14:53 +0000260
261 This is the value to write into CCSR offset 0x18600
262 according to the A004510 workaround.
263
Priyanka Jaine9dcaa82013-12-17 14:25:52 +0530264 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
265 Single Source Clock is clocking mode present in some of FSL SoC's.
266 In this mode, a single differential clock is used to supply
267 clocks to the sysclock, ddrclock and usbclock.
268
Daniel Schwierzeckd8a49ca2012-04-02 02:57:56 +0000269- Generic CPU options:
Daniel Schwierzeckd8a49ca2012-04-02 02:57:56 +0000270
York Sunf0626592013-09-30 09:22:09 -0700271 CONFIG_SYS_FSL_DDR
272 Freescale DDR driver in use. This type of DDR controller is
Tom Rinie5404982021-05-14 21:34:26 -0400273 found in mpc83xx, mpc85xx as well as some ARM core SoCs.
York Sunf0626592013-09-30 09:22:09 -0700274
Tom Rini376b88a2022-10-28 20:27:13 -0400275 CFG_SYS_FSL_DDR_ADDR
York Sunf0626592013-09-30 09:22:09 -0700276 Freescale DDR memory-mapped register base.
277
Prabhakar Kushwaha3c48f582017-02-02 15:01:26 +0530278 CONFIG_SYS_FSL_IFC_CLK_DIV
279 Defines divider of platform clock(clock input to IFC controller).
280
Prabhakar Kushwahabedc5622017-02-02 15:02:00 +0530281 CONFIG_SYS_FSL_LBC_CLK_DIV
282 Defines divider of platform clock(clock input to eLBC controller).
283
Tom Rini376b88a2022-10-28 20:27:13 -0400284 CFG_SYS_FSL_DDR_SDRAM_BASE_PHY
York Sun3a0916d2014-02-10 13:59:43 -0800285 Physical address from the view of DDR controllers. It is the
Tom Rini6a5dccc2022-11-16 13:10:41 -0500286 same as CFG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
York Sun3a0916d2014-02-10 13:59:43 -0800287 it could be different for ARM SoCs.
288
Christian Riesch48c2d6d2012-02-02 00:44:39 +0000289- ARM options:
Tom Rini6a5dccc2022-11-16 13:10:41 -0500290 CFG_SYS_EXCEPTION_VECTORS_HIGH
Christian Riesch48c2d6d2012-02-02 00:44:39 +0000291
292 Select high exception vectors of the ARM core, e.g., do not
293 clear the V bit of the c1 register of CP15.
294
York Sun77a10972015-03-20 19:28:08 -0700295 COUNTER_FREQUENCY
296 Generic timer clock source frequency.
297
298 COUNTER_FREQUENCY_REAL
299 Generic timer clock source frequency if the real clock is
300 different from COUNTER_FREQUENCY, and can only be determined
301 at run time.
302
Stephen Warren8d1fb312015-01-19 16:25:52 -0700303- Tegra SoC options:
304 CONFIG_TEGRA_SUPPORT_NON_SECURE
305
306 Support executing U-Boot in non-secure (NS) mode. Certain
307 impossible actions will be skipped if the CPU is in NS mode,
308 such as ARM architectural timer initialization.
309
wdenk9b7f3842003-10-09 20:09:04 +0000310- Linux Kernel Interface:
Gerald Van Barenfcd91bb2008-06-03 20:34:45 -0400311 CONFIG_OF_LIBFDT
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200312
313 New kernel versions are expecting firmware settings to be
Gerald Van Barend6abef42007-03-31 12:23:51 -0400314 passed using flattened device trees (based on open firmware
315 concepts).
316
317 CONFIG_OF_LIBFDT
318 * New libfdt-based support
319 * Adds the "fdt" command
Kim Phillips9b46eb62007-08-10 14:34:14 -0500320 * The bootm command automatically updates the fdt
Gerald Van Barend6abef42007-03-31 12:23:51 -0400321
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200322 OF_TBCLK - The timebase frequency.
323
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200324 boards with QUICC Engines require OF_QE to set UCC MAC
325 addresses
Kim Phillips9b46eb62007-08-10 14:34:14 -0500326
Heiko Schocherffb293a2009-09-23 07:56:08 +0200327 CONFIG_OF_IDE_FIXUP
328
329 U-Boot can detect if an IDE device is present or not.
330 If not, and this new config option is activated, U-Boot
331 removes the ATA node from the DTS before booting Linux,
332 so the Linux IDE driver does not probe the device and
333 crash. This is needed for buggy hardware (uc101) where
334 no pull down resistor is connected to the signal IDE5V_DD7.
335
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100336- vxWorks boot parameters:
337
338 bootvx constructs a valid bootline using the following
Bin Mengfb694b92015-10-07 20:19:17 -0700339 environments variables: bootdev, bootfile, ipaddr, netmask,
340 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100341 It loads the vxWorks image pointed bootfile.
342
Naoki Hayama158c2262020-10-08 13:17:08 +0900343 Note: If a "bootargs" environment is defined, it will override
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100344 the defaults discussed just above.
345
Aneesh V686a0752011-06-16 23:30:51 +0000346- Cache Configuration for ARM:
Tom Rini6a5dccc2022-11-16 13:10:41 -0500347 CFG_SYS_PL310_BASE - Physical base address of PL310
Aneesh V686a0752011-06-16 23:30:51 +0000348 controller register space
349
wdenkda04a8b2004-08-02 23:22:59 +0000350- Serial Ports:
Tom Rini5c896ae2022-12-04 10:13:30 -0500351 CFG_PL011_CLOCK
wdenkda04a8b2004-08-02 23:22:59 +0000352
353 If you have Amba PrimeCell PL011 UARTs, set this variable to
354 the clock speed of the UARTs.
355
Tom Rini9fe2b312022-12-04 10:13:31 -0500356 CFG_PL01x_PORTS
wdenkda04a8b2004-08-02 23:22:59 +0000357
358 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
359 define this to a list of base addresses for each (supported)
360 port. See e.g. include/configs/versatile.h
361
Karicheri, Muralidharancbc08882014-04-09 15:38:46 -0400362 CONFIG_SERIAL_HW_FLOW_CONTROL
363
364 Define this variable to enable hw flow control in serial driver.
365 Current user of this option is drivers/serial/nsl16550.c driver
wdenkda04a8b2004-08-02 23:22:59 +0000366
Simon Glassaa34ef22016-03-13 19:07:28 -0600367- Removal of commands
368 If no commands are needed to boot, you can disable
369 CONFIG_CMDLINE to remove them. In this case, the command line
370 will not be available, and when U-Boot wants to execute the
371 boot command (on start-up) it will call board_run_command()
372 instead. This can reduce image size significantly for very
373 simple boot procedures.
374
Wolfgang Denk2aceea12013-03-23 23:50:31 +0000375- Regular expression support:
376 CONFIG_REGEX
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200377 If this variable is defined, U-Boot is linked against
378 the SLRE (Super Light Regular Expression) library,
379 which adds regex support to some commands, as for
380 example "env grep" and "setexpr".
Wolfgang Denk2aceea12013-03-23 23:50:31 +0000381
wdenkc6097192002-11-03 00:24:07 +0000382- Watchdog:
Tom Rini364d0022023-01-10 11:19:45 -0500383 CFG_SYS_WATCHDOG_FREQ
Rasmus Villemoes134cc2b2021-04-14 09:18:22 +0200384 Some platforms automatically call WATCHDOG_RESET()
385 from the timer interrupt handler every
Tom Rini364d0022023-01-10 11:19:45 -0500386 CFG_SYS_WATCHDOG_FREQ interrupts. If not set by the
Rasmus Villemoes134cc2b2021-04-14 09:18:22 +0200387 board configuration file, a default of CONFIG_SYS_HZ/2
Tom Rini364d0022023-01-10 11:19:45 -0500388 (i.e. 500) is used. Setting CFG_SYS_WATCHDOG_FREQ
Rasmus Villemoes134cc2b2021-04-14 09:18:22 +0200389 to 0 disables calling WATCHDOG_RESET() from the timer
390 interrupt.
391
Peter Tyser9902e422008-12-17 16:36:21 -0600392- GPIO Support:
Tom Rini6a5dccc2022-11-16 13:10:41 -0500393 The CFG_SYS_I2C_PCA953X_WIDTH option specifies a list of
Chris Packham9b383202010-12-19 10:12:13 +0000394 chip-ngpio pairs that tell the PCA953X driver the number of
395 pins supported by a particular chip.
396
Peter Tyser9902e422008-12-17 16:36:21 -0600397 Note that if the GPIO device uses I2C, then the I2C interface
398 must also be configured. See I2C Support, below.
399
Simon Glass4dc47ca2014-06-11 23:29:41 -0600400- I/O tracing:
401 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
402 accesses and can checksum them or write a list of them out
403 to memory. See the 'iotrace' command for details. This is
404 useful for testing device drivers since it can confirm that
405 the driver behaves the same way before and after a code
406 change. Currently this is supported on sandbox and arm. To
407 add support for your architecture, add '#include <iotrace.h>'
408 to the bottom of arch/<arch>/include/asm/io.h and test.
409
410 Example output from the 'iotrace stats' command is below.
411 Note that if the trace buffer is exhausted, the checksum will
412 still continue to operate.
413
414 iotrace is enabled
415 Start: 10000000 (buffer start address)
416 Size: 00010000 (buffer size)
417 Offset: 00000120 (current buffer offset)
418 Output: 10000120 (start + offset)
419 Count: 00000018 (number of trace records)
420 CRC32: 9526fb66 (CRC32 of all trace records)
421
wdenkc6097192002-11-03 00:24:07 +0000422- Timestamp Support:
423
wdenk4a5c8a72003-03-06 00:02:04 +0000424 When CONFIG_TIMESTAMP is selected, the timestamp
425 (date and time) of an image is printed by image
426 commands like bootm or iminfo. This option is
Jon Loeligerc1da5c92007-06-11 19:03:39 -0500427 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000428
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000429- Partition Labels (disklabels) Supported:
430 Zero or more of the following:
431 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000432 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
433 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
434 bootloader. Note 2TB partition limit; see
435 disk/part_efi.c
Simon Glass8706b812016-05-01 11:36:02 -0600436 CONFIG_SCSI) you must configure support for at
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000437 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000438
wdenkc6097192002-11-03 00:24:07 +0000439- NETWORK Support (PCI):
Kyle Moffett64b94dd2011-10-18 11:05:29 +0000440 CONFIG_E1000_SPI
441 Utility code for direct access to the SPI bus on Intel 8257x.
442 This does not do anything useful unless you set at least one
443 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
444
wdenkc6097192002-11-03 00:24:07 +0000445 CONFIG_NATSEMI
446 Support for National dp83815 chips.
447
448 CONFIG_NS8382X
449 Support for National dp8382[01] gigabit chips.
450
wdenkaa603362003-05-12 21:50:16 +0000451- NETWORK Support (other):
Rob Herringc9830dc2011-12-15 11:15:49 +0000452 CONFIG_CALXEDA_XGMAC
453 Support for the Calxeda XGMAC device
454
Ashok93fb8722012-10-15 06:20:47 +0000455 CONFIG_LAN91C96
wdenkaa603362003-05-12 21:50:16 +0000456 Support for SMSC's LAN91C96 chips.
457
wdenkaa603362003-05-12 21:50:16 +0000458 CONFIG_LAN91C96_USE_32_BIT
459 Define this to enable 32 bit addressing
460
Tom Rini364d0022023-01-10 11:19:45 -0500461 CFG_SYS_DAVINCI_EMAC_PHY_COUNT
Heiko Schocher7d037f72011-11-15 10:00:04 -0500462 Define this if you have more then 3 PHYs.
463
Macpaul Lin199c6252010-12-21 16:59:46 +0800464 CONFIG_FTGMAC100
465 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
466
467 CONFIG_FTGMAC100_EGIGA
468 Define this to use GE link update with gigabit PHY.
469 Define this if FTGMAC100 is connected to gigabit PHY.
470 If your system has 10/100 PHY only, it might not occur
471 wrong behavior. Because PHY usually return timeout or
472 useless data when polling gigabit status and gigabit
473 control registers. This behavior won't affect the
474 correctnessof 10/100 link speed update.
475
Yoshihiro Shimodaed4cea02011-01-27 10:06:03 +0900476 CONFIG_SH_ETHER
477 Support for Renesas on-chip Ethernet controller
478
Tom Rini9996ab82022-12-04 10:13:52 -0500479 CFG_SH_ETHER_USE_PORT
Yoshihiro Shimodaed4cea02011-01-27 10:06:03 +0900480 Define the number of ports to be used
481
Tom Rini45ec5fd2022-12-04 10:13:50 -0500482 CFG_SH_ETHER_PHY_ADDR
Yoshihiro Shimodaed4cea02011-01-27 10:06:03 +0900483 Define the ETH PHY's address
484
Tom Rini872054f2022-12-04 10:13:49 -0500485 CFG_SH_ETHER_CACHE_WRITEBACK
Yoshihiro Shimoda281aa052011-01-27 10:06:08 +0900486 If this option is set, the driver enables cache flush.
487
Vadim Bendeburydac69642011-10-17 08:36:14 +0000488- TPM Support:
Che-liang Chiouacea5702013-04-12 11:04:34 +0000489 CONFIG_TPM
490 Support TPM devices.
491
Christophe Ricard8759ff82015-10-06 22:54:41 +0200492 CONFIG_TPM_TIS_INFINEON
493 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tame49fed52013-04-12 11:04:37 +0000494 per system is supported at this time.
495
Tom Wai-Hong Tame49fed52013-04-12 11:04:37 +0000496 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
497 Define the burst count bytes upper limit
498
Christophe Ricard88249232016-01-21 23:27:13 +0100499 CONFIG_TPM_ST33ZP24
500 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
501
502 CONFIG_TPM_ST33ZP24_I2C
503 Support for STMicroelectronics ST33ZP24 I2C devices.
504 Requires TPM_ST33ZP24 and I2C.
505
Christophe Ricard5ffadc32016-01-21 23:27:14 +0100506 CONFIG_TPM_ST33ZP24_SPI
507 Support for STMicroelectronics ST33ZP24 SPI devices.
508 Requires TPM_ST33ZP24 and SPI.
509
Dirk Eibach20489092013-06-26 15:55:15 +0200510 CONFIG_TPM_ATMEL_TWI
511 Support for Atmel TWI TPM device. Requires I2C support.
512
Che-liang Chiouacea5702013-04-12 11:04:34 +0000513 CONFIG_TPM_TIS_LPC
Vadim Bendeburydac69642011-10-17 08:36:14 +0000514 Support for generic parallel port TPM devices. Only one device
515 per system is supported at this time.
516
Reinhard Pfau4fece432013-06-26 15:55:13 +0200517 CONFIG_TPM
518 Define this to enable the TPM support library which provides
519 functional interfaces to some TPM commands.
520 Requires support for a TPM device.
521
522 CONFIG_TPM_AUTH_SESSIONS
523 Define this to enable authorized functions in the TPM library.
524 Requires CONFIG_TPM and CONFIG_SHA1.
525
wdenkc6097192002-11-03 00:24:07 +0000526- USB Support:
527 At the moment only the UHCI host controller is
Heiko Schocher6f90e582017-06-14 05:49:40 +0200528 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +0000529 CONFIG_USB_UHCI to enable it.
530 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenkfb30b4c2004-10-09 22:44:59 +0000531 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +0000532 storage devices.
533 Note:
534 Supported are USB Keyboards and USB Floppy drives
535 (TEAC FD-05PUB).
wdenk369d43d2004-03-14 14:09:05 +0000536
Oleksandr Tymoshenko7a881752014-02-01 21:51:25 -0700537 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
538 HW module registers.
539
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200540- USB Device:
541 Define the below if you wish to use the USB console.
542 Once firmware is rebuilt from a serial console issue the
543 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200544 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200545 it has found a new device. The environment variable usbtty
546 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denke2601822006-06-14 18:14:56 +0200547 appear to a USB host as a Linux gserial device or a
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200548 Common Device Class Abstract Control Model serial device.
549 If you select usbtty = gserial you should be able to enumerate
550 a Linux host by
551 # modprobe usbserial vendor=0xVendorID product=0xProductID
552 else if using cdc_acm, simply setting the environment
553 variable usbtty to be cdc_acm should suffice. The following
554 might be defined in YourBoardName.h
Wolfgang Denke2601822006-06-14 18:14:56 +0200555
Wolfgang Denke2601822006-06-14 18:14:56 +0200556 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200557 define your own vendor specific values either in BoardName.h
Wolfgang Denke2601822006-06-14 18:14:56 +0200558 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200559 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
560 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
561 should pretend to be a Linux device to it's target host.
562
563 CONFIG_USBD_MANUFACTURER
564 Define this string as the name of your company for
565 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denke2601822006-06-14 18:14:56 +0200566
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200567 CONFIG_USBD_PRODUCT_NAME
568 Define this string as the name of your product
569 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
wdenkc6097192002-11-03 00:24:07 +0000570
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200571 CONFIG_USBD_VENDORID
572 Define this as your assigned Vendor ID from the USB
573 Implementors Forum. This *must* be a genuine Vendor ID
574 to avoid polluting the USB namespace.
575 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denke2601822006-06-14 18:14:56 +0200576
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200577 CONFIG_USBD_PRODUCTID
578 Define this as the unique Product ID
579 for your device
580 - CONFIG_USBD_PRODUCTID 0xFFFF
Wolfgang Denke2601822006-06-14 18:14:56 +0200581
Igor Grinbergac5f6ee2011-12-12 12:08:35 +0200582- ULPI Layer Support:
583 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
584 the generic ULPI layer. The generic layer accesses the ULPI PHY
585 via the platform viewport, so you need both the genric layer and
586 the viewport enabled. Currently only Chipidea/ARC based
587 viewport is supported.
588 To enable the ULPI layer support, define CONFIG_USB_ULPI and
589 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stachf31e4112012-10-01 00:44:35 +0200590 If your ULPI phy needs a different reference clock than the
Tom Rini364d0022023-01-10 11:19:45 -0500591 standard 24 MHz then you have to define CFG_ULPI_REF_CLK to
Lucas Stachf31e4112012-10-01 00:44:35 +0200592 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +0000593
wdenk7a428cc2003-06-15 22:40:42 +0000594- MMC Support:
Yoshihiro Shimodadb7717b2011-07-04 22:21:22 +0000595 CONFIG_SH_MMCIF
596 Support for Renesas on-chip MMCIF controller
597
598 CONFIG_SH_MMCIF_ADDR
599 Define the base address of MMCIF registers
600
601 CONFIG_SH_MMCIF_CLK
602 Define the clock frequency for MMCIF
603
Tom Rini58a8d322013-03-14 05:32:47 +0000604- USB Device Firmware Update (DFU) class support:
Marek Vasut7f8d4362018-02-16 16:41:18 +0100605 CONFIG_DFU_OVER_USB
Tom Rini58a8d322013-03-14 05:32:47 +0000606 This enables the USB portion of the DFU USB class
607
Pantelis Antonioucf14d0d2013-03-14 05:32:52 +0000608 CONFIG_DFU_NAND
609 This enables support for exposing NAND devices via DFU.
610
Afzal Mohammede3c687a2013-09-18 01:15:24 +0530611 CONFIG_DFU_RAM
612 This enables support for exposing RAM via DFU.
613 Note: DFU spec refer to non-volatile memory usage, but
614 allow usages beyond the scope of spec - here RAM usage,
615 one that would help mostly the developer.
616
Heiko Schochera2f831e2013-06-12 06:05:51 +0200617 CONFIG_SYS_DFU_DATA_BUF_SIZE
618 Dfu transfer uses a buffer before writing data to the
619 raw storage device. Make the size (in bytes) of this buffer
620 configurable. The size of this buffer is also configurable
621 through the "dfu_bufsiz" environment variable.
622
Pantelis Antonioua6e788d2013-03-14 05:32:48 +0000623 CONFIG_SYS_DFU_MAX_FILE_SIZE
624 When updating files rather than the raw storage device,
625 we use a static buffer to copy the file into and then write
626 the buffer once we've been given the whole file. Define
627 this to the maximum filesize (in bytes) for the buffer.
628 Default is 4 MiB if undefined.
629
Heiko Schochere1ba1512014-03-18 08:09:56 +0100630 DFU_DEFAULT_POLL_TIMEOUT
631 Poll timeout [ms], is the timeout a device can send to the
632 host. The host must wait for this timeout before sending
633 a subsequent DFU_GET_STATUS request to the device.
634
635 DFU_MANIFEST_POLL_TIMEOUT
636 Poll timeout [ms], which the device sends to the host when
637 entering dfuMANIFEST state. Host waits this timeout, before
638 sending again an USB request to the device.
639
wdenkc6097192002-11-03 00:24:07 +0000640- Keyboard Support:
Simon Glasseaba37e2015-11-11 10:05:47 -0700641 See Kconfig help for available keyboard drivers.
642
wdenk0e2bd9c2004-06-06 21:51:03 +0000643- MII/PHY support:
wdenk0e2bd9c2004-06-06 21:51:03 +0000644 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
645
646 The clock frequency of the MII bus
647
wdenk0e2bd9c2004-06-06 21:51:03 +0000648 CONFIG_PHY_CMD_DELAY (ppc4xx)
649
650 Some PHY like Intel LXT971A need extra delay after
651 command issued before MII status register can be read
652
wdenkc6097192002-11-03 00:24:07 +0000653- BOOTP Recovery Mode:
654 CONFIG_BOOTP_RANDOM_DELAY
655
656 If you have many targets in a network that try to
657 boot using BOOTP, you may want to avoid that all
658 systems send out BOOTP requests at precisely the same
659 moment (which would happen for instance at recovery
660 from a power failure, when all systems will try to
661 boot, thus flooding the BOOTP server. Defining
662 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
663 inserted before sending out BOOTP requests. The
Wolfgang Denkb65aaf92007-08-06 23:21:05 +0200664 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +0000665
666 1st BOOTP request: delay 0 ... 1 sec
667 2nd BOOTP request: delay 0 ... 2 sec
668 3rd BOOTP request: delay 0 ... 4 sec
669 4th and following
670 BOOTP requests: delay 0 ... 8 sec
671
Tom Rini364d0022023-01-10 11:19:45 -0500672 CFG_BOOTP_ID_CACHE_SIZE
Thierry Reding8977cda2014-08-19 10:21:24 +0200673
674 BOOTP packets are uniquely identified using a 32-bit ID. The
675 server will copy the ID from client requests to responses and
676 U-Boot will use this to determine if it is the destination of
677 an incoming response. Some servers will check that addresses
678 aren't in use before handing them out (usually using an ARP
679 ping) and therefore take up to a few hundred milliseconds to
680 respond. Network congestion may also influence the time it
681 takes for a response to make it back to the client. If that
682 time is too long, U-Boot will retransmit requests. In order
683 to allow earlier responses to still be accepted after these
684 retransmissions, U-Boot's BOOTP client keeps a small cache of
Tom Rini364d0022023-01-10 11:19:45 -0500685 IDs. The CFG_BOOTP_ID_CACHE_SIZE controls the size of this
Thierry Reding8977cda2014-08-19 10:21:24 +0200686 cache. The default is to keep IDs for up to four outstanding
687 requests. Increasing this will allow U-Boot to accept offers
688 from a BOOTP client in networks with unusually high latency.
689
stroesee0aadfb2003-08-28 14:17:32 +0000690- DHCP Advanced Options:
Joe Hershberger8ca7fa02012-05-23 07:59:19 +0000691
Joe Hershbergerb35a3a62012-05-23 08:00:12 +0000692 - Link-local IP address negotiation:
693 Negotiate with other link-local clients on the local network
694 for an address that doesn't require explicit configuration.
695 This is especially useful if a DHCP server cannot be guaranteed
696 to exist in all environments that the device must operate.
697
698 See doc/README.link-local for more information.
699
Prabhakar Kushwaha2dec06f2017-11-23 16:51:32 +0530700 - MAC address from environment variables
701
702 FDT_SEQ_MACADDR_FROM_ENV
703
704 Fix-up device tree with MAC addresses fetched sequentially from
705 environment variables. This config work on assumption that
706 non-usable ethernet node of device-tree are either not present
707 or their status has been marked as "disabled".
708
wdenk145d2c12004-04-15 21:48:45 +0000709 - CDP Options:
wdenk05939202004-04-18 17:39:38 +0000710 CONFIG_CDP_DEVICE_ID
wdenk145d2c12004-04-15 21:48:45 +0000711
712 The device id used in CDP trigger frames.
713
714 CONFIG_CDP_DEVICE_ID_PREFIX
715
716 A two character string which is prefixed to the MAC address
717 of the device.
718
719 CONFIG_CDP_PORT_ID
720
721 A printf format string which contains the ascii name of
722 the port. Normally is set to "eth%d" which sets
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200723 eth0 for the first Ethernet, eth1 for the second etc.
wdenk145d2c12004-04-15 21:48:45 +0000724
725 CONFIG_CDP_CAPABILITIES
726
727 A 32bit integer which indicates the device capabilities;
728 0x00000010 for a normal host which does not forwards.
729
730 CONFIG_CDP_VERSION
731
732 An ascii string containing the version of the software.
733
734 CONFIG_CDP_PLATFORM
735
736 An ascii string containing the name of the platform.
737
738 CONFIG_CDP_TRIGGER
739
740 A 32bit integer sent on the trigger.
741
742 CONFIG_CDP_POWER_CONSUMPTION
743
744 A 16bit integer containing the power consumption of the
745 device in .1 of milliwatts.
746
747 CONFIG_CDP_APPLIANCE_VLAN_TYPE
748
749 A byte containing the id of the VLAN.
750
Uri Mashiach3dc6f652017-01-19 10:51:05 +0200751- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +0000752
753 Several configurations allow to display the current
754 status using a LED. For instance, the LED will blink
755 fast while running U-Boot code, stop blinking as
756 soon as a reply to a BOOTP request was received, and
757 start blinking slow once the Linux kernel is running
758 (supported by a status LED driver in the Linux
Uri Mashiach3dc6f652017-01-19 10:51:05 +0200759 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +0000760 feature in U-Boot.
761
Igor Grinberg4997a9e2013-11-08 01:03:50 +0200762 Additional options:
763
Uri Mashiach3dc6f652017-01-19 10:51:05 +0200764 CONFIG_LED_STATUS_GPIO
Igor Grinberg4997a9e2013-11-08 01:03:50 +0200765 The status LED can be connected to a GPIO pin.
766 In such cases, the gpio_led driver can be used as a
Uri Mashiach3dc6f652017-01-19 10:51:05 +0200767 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg4997a9e2013-11-08 01:03:50 +0200768 to include the gpio_led driver in the U-Boot binary.
769
Tom Rini364d0022023-01-10 11:19:45 -0500770 CFG_GPIO_LED_INVERTED_TABLE
Igor Grinberg203bd9f2013-11-08 01:03:52 +0200771 Some GPIO connected LEDs may have inverted polarity in which
772 case the GPIO high value corresponds to LED off state and
773 GPIO low value corresponds to LED on state.
Tom Rini364d0022023-01-10 11:19:45 -0500774 In such cases CFG_GPIO_LED_INVERTED_TABLE may be defined
Igor Grinberg203bd9f2013-11-08 01:03:52 +0200775 with a list of GPIO LEDs that have inverted polarity.
776
Tom Rini52b2e262021-08-18 23:12:24 -0400777- I2C Support:
Tom Rini0a2bac72022-11-16 13:10:29 -0500778 CFG_SYS_NUM_I2C_BUSES
Simon Glassb05e2b32016-10-02 18:01:05 -0600779 Hold the number of i2c buses you want to use.
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000780
Tom Rini76627362022-12-04 10:13:57 -0500781 CFG_SYS_I2C_DIRECT_BUS
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000782 define this, if you don't use i2c muxes on your hardware.
Tom Rini6a5dccc2022-11-16 13:10:41 -0500783 if CFG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000784 omit this define.
785
Tom Rini6a5dccc2022-11-16 13:10:41 -0500786 CFG_SYS_I2C_MAX_HOPS
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000787 define how many muxes are maximal consecutively connected
788 on one i2c bus. If you not use i2c muxes, omit this
789 define.
790
Tom Rini6a5dccc2022-11-16 13:10:41 -0500791 CFG_SYS_I2C_BUSES
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800792 hold a list of buses you want to use, only used if
Tom Rini76627362022-12-04 10:13:57 -0500793 CFG_SYS_I2C_DIRECT_BUS is not defined, for example
Tom Rini6a5dccc2022-11-16 13:10:41 -0500794 a board with CFG_SYS_I2C_MAX_HOPS = 1 and
Tom Rini0a2bac72022-11-16 13:10:29 -0500795 CFG_SYS_NUM_I2C_BUSES = 9:
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000796
Tom Rini6a5dccc2022-11-16 13:10:41 -0500797 CFG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000798 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
799 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
800 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
801 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
802 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
803 {1, {I2C_NULL_HOP}}, \
804 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
805 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
806 }
807
808 which defines
809 bus 0 on adapter 0 without a mux
Heiko Schocher479a4cf2013-01-29 08:53:15 +0100810 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
811 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
812 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
813 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
814 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000815 bus 6 on adapter 1 without a mux
Heiko Schocher479a4cf2013-01-29 08:53:15 +0100816 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
817 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000818
819 If you do not have i2c muxes on your board, omit this define.
820
Simon Glass3efce392017-05-12 21:10:00 -0600821- Legacy I2C Support:
Heiko Schocher479a4cf2013-01-29 08:53:15 +0100822 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb9bbd242003-06-30 16:24:52 +0000823 then the following macros need to be defined (examples are
824 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +0000825
826 I2C_INIT
827
wdenkb9bbd242003-06-30 16:24:52 +0000828 (Optional). Any commands necessary to enable the I2C
wdenk4a5c8a72003-03-06 00:02:04 +0000829 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +0000830
wdenk544e9732004-02-06 23:19:44 +0000831 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb9bbd242003-06-30 16:24:52 +0000832
wdenkc6097192002-11-03 00:24:07 +0000833 I2C_ACTIVE
834
835 The code necessary to make the I2C data line active
836 (driven). If the data line is open collector, this
837 define can be null.
838
wdenkb9bbd242003-06-30 16:24:52 +0000839 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
840
wdenkc6097192002-11-03 00:24:07 +0000841 I2C_TRISTATE
842
843 The code necessary to make the I2C data line tri-stated
844 (inactive). If the data line is open collector, this
845 define can be null.
846
wdenkb9bbd242003-06-30 16:24:52 +0000847 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
848
wdenkc6097192002-11-03 00:24:07 +0000849 I2C_READ
850
York Sun4a598092013-04-01 11:29:11 -0700851 Code that returns true if the I2C data line is high,
852 false if it is low.
wdenkc6097192002-11-03 00:24:07 +0000853
wdenkb9bbd242003-06-30 16:24:52 +0000854 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
855
wdenkc6097192002-11-03 00:24:07 +0000856 I2C_SDA(bit)
857
York Sun4a598092013-04-01 11:29:11 -0700858 If <bit> is true, sets the I2C data line high. If it
859 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +0000860
wdenkb9bbd242003-06-30 16:24:52 +0000861 eg: #define I2C_SDA(bit) \
wdenk2bb11052003-07-17 23:16:40 +0000862 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenk544e9732004-02-06 23:19:44 +0000863 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb9bbd242003-06-30 16:24:52 +0000864
wdenkc6097192002-11-03 00:24:07 +0000865 I2C_SCL(bit)
866
York Sun4a598092013-04-01 11:29:11 -0700867 If <bit> is true, sets the I2C clock line high. If it
868 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +0000869
wdenkb9bbd242003-06-30 16:24:52 +0000870 eg: #define I2C_SCL(bit) \
wdenk2bb11052003-07-17 23:16:40 +0000871 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenk544e9732004-02-06 23:19:44 +0000872 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb9bbd242003-06-30 16:24:52 +0000873
wdenkc6097192002-11-03 00:24:07 +0000874 I2C_DELAY
875
876 This delay is invoked four times per clock cycle so this
877 controls the rate of data transfer. The data rate thus
wdenkb9bbd242003-06-30 16:24:52 +0000878 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk21136db2003-07-16 21:53:01 +0000879 like:
880
wdenkb9bbd242003-06-30 16:24:52 +0000881 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +0000882
Mike Frysingeree12d542010-07-21 13:38:02 -0400883 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
884
885 If your arch supports the generic GPIO framework (asm/gpio.h),
886 then you may alternatively define the two GPIOs that are to be
887 used as SCL / SDA. Any of the previous I2C_xxx macros will
888 have GPIO-based defaults assigned to them as appropriate.
889
890 You should define these to the GPIO value as given directly to
891 the generic GPIO functions.
892
Tom Rini8227d052022-12-04 10:04:08 -0500893 CFG_I2C_MULTI_BUS
Ben Warren45657152006-09-07 16:50:54 -0400894
895 This option allows the use of multiple I2C buses, each of which
Wolfgang Denk092ae952011-10-26 10:21:21 +0000896 must have a controller. At any point in time, only one bus is
897 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warren45657152006-09-07 16:50:54 -0400898 Note that bus numbering is zero-based.
899
Tom Rini6a5dccc2022-11-16 13:10:41 -0500900 CFG_SYS_I2C_NOPROBES
Ben Warren45657152006-09-07 16:50:54 -0400901
902 This option specifies a list of I2C devices that will be skipped
Tom Rini6da96a12022-12-02 16:42:30 -0500903 when the 'i2c probe' command is issued.
Ben Warren45657152006-09-07 16:50:54 -0400904
905 e.g.
Tom Rini6a5dccc2022-11-16 13:10:41 -0500906 #define CFG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warren45657152006-09-07 16:50:54 -0400907
908 will skip addresses 0x50 and 0x68 on a board with one I2C bus
909
Tom Rini6a5dccc2022-11-16 13:10:41 -0500910 CFG_SYS_RTC_BUS_NUM
Stefan Roese096cc9b2007-02-20 10:51:26 +0100911
912 If defined, then this indicates the I2C bus number for the RTC.
913 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
914
Andrew Dyer58c41f92008-12-29 17:36:01 -0600915 CONFIG_SOFT_I2C_READ_REPEATED_START
916
917 defining this will force the i2c_read() function in
918 the soft_i2c driver to perform an I2C repeated start
919 between writing the address pointer and reading the
920 data. If this define is omitted the default behaviour
921 of doing a stop-start sequence will be used. Most I2C
922 devices can use either method, but some require one or
923 the other.
Timur Tabiab347542006-11-03 19:15:00 -0600924
wdenkc6097192002-11-03 00:24:07 +0000925- SPI Support: CONFIG_SPI
926
927 Enables SPI driver (so far only tested with
928 SPI EEPROM, also an instance works with Crystal A/D and
929 D/As on the SACSng board)
930
Tom Rini364d0022023-01-10 11:19:45 -0500931 CFG_SYS_SPI_MXC_WAIT
Heiko Schocherb77c8882014-07-14 10:22:11 +0200932 Timeout for waiting until spi transfer completed.
933 default: (CONFIG_SYS_HZ/100) /* 10 ms */
934
Matthias Fuchsa4400872007-12-27 17:12:34 +0100935- FPGA Support: CONFIG_FPGA
wdenkc6097192002-11-03 00:24:07 +0000936
Matthias Fuchsa4400872007-12-27 17:12:34 +0100937 Enables FPGA subsystem.
938
939 CONFIG_FPGA_<vendor>
940
941 Enables support for specific chip vendors.
942 (ALTERA, XILINX)
wdenkc6097192002-11-03 00:24:07 +0000943
Matthias Fuchsa4400872007-12-27 17:12:34 +0100944 CONFIG_FPGA_<family>
wdenkc6097192002-11-03 00:24:07 +0000945
Matthias Fuchsa4400872007-12-27 17:12:34 +0100946 Enables support for FPGA family.
947 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
948
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +0200949 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +0000950
wdenk4a5c8a72003-03-06 00:02:04 +0000951 Enable checks on FPGA configuration interface busy
952 status by the configuration function. This option
953 will require a board or device specific function to
954 be written.
wdenkc6097192002-11-03 00:24:07 +0000955
Tom Rini88d86ec2022-12-04 10:03:57 -0500956 CFG_FPGA_DELAY
wdenkc6097192002-11-03 00:24:07 +0000957
958 If defined, a function that provides delays in the FPGA
959 configuration driver.
960
Tom Rini364d0022023-01-10 11:19:45 -0500961 CFG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +0000962
wdenk4a5c8a72003-03-06 00:02:04 +0000963 Check for configuration errors during FPGA bitfile
964 loading. For example, abort during Virtex II
965 configuration if the INIT_B line goes low (which
966 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +0000967
Tom Rini6a5dccc2022-11-16 13:10:41 -0500968 CFG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +0000969
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800970 Maximum time to wait for the INIT_B line to de-assert
971 after PROB_B has been de-asserted during a Virtex II
wdenk4a5c8a72003-03-06 00:02:04 +0000972 FPGA configuration sequence. The default time is 500
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200973 ms.
wdenkc6097192002-11-03 00:24:07 +0000974
Tom Rini6a5dccc2022-11-16 13:10:41 -0500975 CFG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +0000976
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800977 Maximum time to wait for BUSY to de-assert during
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200978 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +0000979
Tom Rini6a5dccc2022-11-16 13:10:41 -0500980 CFG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +0000981
wdenk4a5c8a72003-03-06 00:02:04 +0000982 Time to wait after FPGA configuration. The default is
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200983 200 ms.
wdenkc6097192002-11-03 00:24:07 +0000984
wdenkc6097192002-11-03 00:24:07 +0000985- Vendor Parameter Protection:
986
wdenk4a5c8a72003-03-06 00:02:04 +0000987 U-Boot considers the values of the environment
988 variables "serial#" (Board Serial Number) and
wdenkeb20ad32003-09-05 23:19:14 +0000989 "ethaddr" (Ethernet Address) to be parameters that
wdenk4a5c8a72003-03-06 00:02:04 +0000990 are set once by the board vendor / manufacturer, and
991 protects these variables from casual modification by
992 the user. Once set, these variables are read-only,
993 and write or delete attempts are rejected. You can
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200994 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +0000995
996 If CONFIG_ENV_OVERWRITE is #defined in your config
997 file, the write protection for vendor parameters is
wdenkcc1e2562003-03-06 13:39:27 +0000998 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +0000999 these parameters.
1000
Joe Hershberger71497d02012-12-11 22:16:31 -06001001 The same can be accomplished in a more flexible way
1002 for any variable by configuring the type of access
1003 to allow for those variables in the ".flags" variable
Tom Rini0297e5f2022-12-04 10:03:40 -05001004 or define CFG_ENV_FLAGS_LIST_STATIC.
Joe Hershberger71497d02012-12-11 22:16:31 -06001005
wdenkc6097192002-11-03 00:24:07 +00001006- Protected RAM:
Tom Rini0bb9b092022-12-04 10:13:37 -05001007 CFG_PRAM
wdenkc6097192002-11-03 00:24:07 +00001008
1009 Define this variable to enable the reservation of
1010 "protected RAM", i. e. RAM which is not overwritten
Tom Rini0bb9b092022-12-04 10:13:37 -05001011 by U-Boot. Define CFG_PRAM to hold the number of
wdenkc6097192002-11-03 00:24:07 +00001012 kB you want to reserve for pRAM. You can overwrite
1013 this default value by defining an environment
1014 variable "pram" to the number of kB you want to
1015 reserve. Note that the board info structure will
1016 still show the full amount of RAM. If pRAM is
1017 reserved, a new environment variable "mem" will
1018 automatically be defined to hold the amount of
1019 remaining RAM in a form that can be passed as boot
1020 argument to Linux, for instance like that:
1021
Wolfgang Denk86eb3b72005-11-20 21:40:11 +01001022 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00001023 saveenv
1024
1025 This way you can tell Linux not to use this memory,
1026 either, which results in a memory region that will
1027 not be affected by reboots.
1028
1029 *WARNING* If your board configuration uses automatic
1030 detection of the RAM size, you must make sure that
1031 this memory test is non-destructive. So far, the
1032 following board configurations are known to be
1033 "pRAM-clean":
1034
Heiko Schocher65d94db2017-06-07 17:33:09 +02001035 IVMS8, IVML24, SPD8xx,
Wolfgang Denk90326762012-10-24 02:36:15 +00001036 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher71cb3e92017-06-07 17:33:10 +02001037 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00001038
1039- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00001040 Note:
1041
wdenk57b2d802003-06-27 21:31:46 +00001042 In the current implementation, the local variables
1043 space and global environment variables space are
1044 separated. Local variables are those you define by
1045 simply typing `name=value'. To access a local
1046 variable later on, you have write `$name' or
1047 `${name}'; to execute the contents of a variable
1048 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00001049
wdenk4a5c8a72003-03-06 00:02:04 +00001050 Global environment variables are those you use
1051 setenv/printenv to work with. To run a command stored
1052 in such a variable, you need to use the run command,
1053 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00001054
1055 To store commands and special characters in a
1056 variable, please use double quotation marks
1057 surrounding the whole text of the variable, instead
1058 of the backslashes before semicolons and special
1059 symbols.
1060
wdenkc0aa5c52003-12-06 19:49:23 +00001061- Default Environment:
Tom Rinic9edebe2022-12-04 10:03:50 -05001062 CFG_EXTRA_ENV_SETTINGS
wdenkc6097192002-11-03 00:24:07 +00001063
wdenk4a5c8a72003-03-06 00:02:04 +00001064 Define this to contain any number of null terminated
1065 strings (variable = value pairs) that will be part of
wdenkeb20ad32003-09-05 23:19:14 +00001066 the default environment compiled into the boot image.
wdenk591dda52002-11-18 00:14:45 +00001067
wdenk4a5c8a72003-03-06 00:02:04 +00001068 For example, place something like this in your
1069 board's config file:
wdenkc6097192002-11-03 00:24:07 +00001070
Tom Rinic9edebe2022-12-04 10:03:50 -05001071 #define CFG_EXTRA_ENV_SETTINGS \
wdenkc6097192002-11-03 00:24:07 +00001072 "myvar1=value1\0" \
1073 "myvar2=value2\0"
1074
wdenk4a5c8a72003-03-06 00:02:04 +00001075 Warning: This method is based on knowledge about the
1076 internal format how the environment is stored by the
1077 U-Boot code. This is NOT an official, exported
1078 interface! Although it is unlikely that this format
wdenkeb20ad32003-09-05 23:19:14 +00001079 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00001080 You better know what you are doing here.
1081
wdenk4a5c8a72003-03-06 00:02:04 +00001082 Note: overly (ab)use of the default environment is
1083 discouraged. Make sure to check other ways to preset
Wolfgang Denk85c25df2009-04-01 23:34:12 +02001084 the environment like the "source" command or the
wdenk4a5c8a72003-03-06 00:02:04 +00001085 boot command first.
wdenkc6097192002-11-03 00:24:07 +00001086
Simon Glass6b8d5fd2012-11-30 13:01:17 +00001087 CONFIG_DELAY_ENVIRONMENT
1088
1089 Normally the environment is loaded when the board is
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001090 initialised so that it is available to U-Boot. This inhibits
Simon Glass6b8d5fd2012-11-30 13:01:17 +00001091 that so that the environment is not available until
1092 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
1093 this is instead controlled by the value of
1094 /config/load-environment.
1095
Detlev Zundel0ecb6112009-12-01 17:16:19 +01001096- Automatic software updates via TFTP server
1097 CONFIG_UPDATE_TFTP
1098 CONFIG_UPDATE_TFTP_CNT_MAX
1099 CONFIG_UPDATE_TFTP_MSEC_MAX
1100
1101 These options enable and control the auto-update feature;
1102 for a more detailed description refer to doc/README.update.
1103
1104- MTD Support (mtdparts command, UBI support)
Heiko Schocherf5895d12014-06-24 10:10:04 +02001105 CONFIG_MTD_UBI_WL_THRESHOLD
1106 This parameter defines the maximum difference between the highest
1107 erase counter value and the lowest erase counter value of eraseblocks
1108 of UBI devices. When this threshold is exceeded, UBI starts performing
1109 wear leveling by means of moving data from eraseblock with low erase
1110 counter to eraseblocks with high erase counter.
1111
1112 The default value should be OK for SLC NAND flashes, NOR flashes and
1113 other flashes which have eraseblock life-cycle 100000 or more.
1114 However, in case of MLC NAND flashes which typically have eraseblock
1115 life-cycle less than 10000, the threshold should be lessened (e.g.,
1116 to 128 or 256, although it does not have to be power of 2).
1117
1118 default: 4096
Simon Glass6c0be912014-10-23 18:58:54 -06001119
Heiko Schocherf5895d12014-06-24 10:10:04 +02001120 CONFIG_MTD_UBI_BEB_LIMIT
1121 This option specifies the maximum bad physical eraseblocks UBI
1122 expects on the MTD device (per 1024 eraseblocks). If the
1123 underlying flash does not admit of bad eraseblocks (e.g. NOR
1124 flash), this value is ignored.
1125
1126 NAND datasheets often specify the minimum and maximum NVM
1127 (Number of Valid Blocks) for the flashes' endurance lifetime.
1128 The maximum expected bad eraseblocks per 1024 eraseblocks
1129 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
1130 which gives 20 for most NANDs (MaxNVB is basically the total
1131 count of eraseblocks on the chip).
1132
1133 To put it differently, if this value is 20, UBI will try to
1134 reserve about 1.9% of physical eraseblocks for bad blocks
1135 handling. And that will be 1.9% of eraseblocks on the entire
1136 NAND chip, not just the MTD partition UBI attaches. This means
1137 that if you have, say, a NAND flash chip admits maximum 40 bad
1138 eraseblocks, and it is split on two MTD partitions of the same
1139 size, UBI will reserve 40 eraseblocks when attaching a
1140 partition.
1141
1142 default: 20
1143
1144 CONFIG_MTD_UBI_FASTMAP
1145 Fastmap is a mechanism which allows attaching an UBI device
1146 in nearly constant time. Instead of scanning the whole MTD device it
1147 only has to locate a checkpoint (called fastmap) on the device.
1148 The on-flash fastmap contains all information needed to attach
1149 the device. Using fastmap makes only sense on large devices where
1150 attaching by scanning takes long. UBI will not automatically install
1151 a fastmap on old images, but you can set the UBI parameter
1152 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
1153 that fastmap-enabled images are still usable with UBI implementations
1154 without fastmap support. On typical flash devices the whole fastmap
1155 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
1156
1157 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
1158 Set this parameter to enable fastmap automatically on images
1159 without a fastmap.
1160 default: 0
1161
Heiko Schocher94b66de2015-10-22 06:19:21 +02001162 CONFIG_MTD_UBI_FM_DEBUG
1163 Enable UBI fastmap debug
1164 default: 0
1165
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00001166- SPL framework
Wolfgang Denk825223d2011-09-11 21:24:09 +02001167 CONFIG_SPL
1168 Enable building of SPL globally.
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00001169
Albert ARIBAUD \(3ADEV\)287b0942015-03-31 11:40:50 +02001170 CONFIG_SPL_PANIC_ON_RAW_IMAGE
1171 When defined, SPL will panic() if the image it has
1172 loaded does not have a signature.
1173 Defining this is useful when code which loads images
1174 in SPL cannot guarantee that absolutely all read errors
1175 will be caught.
1176 An example is the LPC32XX MLC NAND driver, which will
1177 consider that a completely unreadable NAND block is bad,
1178 and thus should be skipped silently.
1179
Tom Rinife3b0c72012-08-13 11:37:56 -07001180 CONFIG_SPL_DISPLAY_PRINT
1181 For ARM, enable an optional function to print more information
1182 about the running system.
1183
Scott Wood2b36fbb2012-12-06 13:33:17 +00001184 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
1185 Set this for NAND SPL on PPC mpc83xx targets, so that
1186 start.S waits for the rest of the SPL to load before
1187 continuing (the hardware starts execution after just
1188 loading the first page rather than the full 4K).
1189
Thomas Gleixner820d24d2016-07-12 20:28:12 +02001190 CONFIG_SPL_UBI
1191 Support for a lightweight UBI (fastmap) scanner and
1192 loader
1193
Tom Rini36853852012-02-14 07:29:40 +00001194 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
1195 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
1196 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
Tom Rinib4213492022-11-12 17:36:51 -05001197 CFG_SYS_NAND_ECCPOS, CFG_SYS_NAND_ECCSIZE,
1198 CFG_SYS_NAND_ECCBYTES
Tom Rini36853852012-02-14 07:29:40 +00001199 Defines the size and behavior of the NAND that SPL uses
Scott Wood36c440e2012-09-21 18:35:27 -05001200 to read U-Boot
Tom Rini36853852012-02-14 07:29:40 +00001201
Tom Rinib4213492022-11-12 17:36:51 -05001202 CFG_SYS_NAND_U_BOOT_DST
Scott Wood36c440e2012-09-21 18:35:27 -05001203 Location in memory to load U-Boot to
1204
Tom Rinib4213492022-11-12 17:36:51 -05001205 CFG_SYS_NAND_U_BOOT_SIZE
Scott Wood36c440e2012-09-21 18:35:27 -05001206 Size of image to load
Tom Rini36853852012-02-14 07:29:40 +00001207
Tom Rinib4213492022-11-12 17:36:51 -05001208 CFG_SYS_NAND_U_BOOT_START
Scott Wood36c440e2012-09-21 18:35:27 -05001209 Entry point in loaded image to jump to
Tom Rini36853852012-02-14 07:29:40 +00001210
Pavel Machekde997252012-08-30 22:42:11 +02001211 CONFIG_SPL_RAM_DEVICE
1212 Support for running image already present in ram, in SPL binary
1213
Marek Vasut9f2e0eb2018-05-13 00:22:52 +02001214 CONFIG_SPL_FIT_PRINT
Simon Glass82d94532013-05-08 08:05:59 +00001215 Printing information about a FIT image adds quite a bit of
1216 code to SPL. So this is normally disabled in SPL. Use this
1217 option to re-enable it. This will affect the output of the
1218 bootm command when booting a FIT image.
1219
wdenkc0aa5c52003-12-06 19:49:23 +00001220- Interrupt support (PPC):
1221
wdenk1ebf41e2004-01-02 14:00:00 +00001222 There are common interrupt_init() and timer_interrupt()
1223 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001224 for CPU specific initialization. interrupt_init_cpu()
wdenk1ebf41e2004-01-02 14:00:00 +00001225 should set decrementer_count to appropriate value. If
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001226 CPU resets decrementer automatically after interrupt
wdenk1ebf41e2004-01-02 14:00:00 +00001227 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001228 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenk1ebf41e2004-01-02 14:00:00 +00001229 specific handling. If board has watchdog / status_led
1230 / other_activity_monitor it works automatically from
1231 general timer_interrupt().
wdenkc0aa5c52003-12-06 19:49:23 +00001232
wdenkc6097192002-11-03 00:24:07 +00001233
Helmut Raigerd5a184b2011-10-20 04:19:47 +00001234Board initialization settings:
1235------------------------------
1236
1237During Initialization u-boot calls a number of board specific functions
1238to allow the preparation of board specific prerequisites, e.g. pin setup
1239before drivers are initialized. To enable these callbacks the
1240following configuration macros have to be defined. Currently this is
1241architecture specific, so please check arch/your_architecture/lib/board.c
1242typically in board_init_f() and board_init_r().
1243
1244- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
1245- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
1246- CONFIG_BOARD_LATE_INIT: Call board_late_init()
wdenkc6097192002-11-03 00:24:07 +00001247
wdenkc6097192002-11-03 00:24:07 +00001248Configuration Settings:
1249-----------------------
1250
Simon Glass8927bf22019-12-28 10:45:10 -07001251- MEM_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
York Sun6c480012014-02-26 17:03:19 -08001252 Optionally it can be defined to support 64-bit memory commands.
1253
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001254- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00001255 undefine this when you're short of memory.
1256
Tom Rini364d0022023-01-10 11:19:45 -05001257- CFG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
Peter Tyserdfb72b82009-01-27 18:03:12 -06001258 width of the commands listed in the 'help' command output.
1259
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001260- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00001261 prompt for user input.
1262
Tom Rini6a5dccc2022-11-16 13:10:41 -05001263- CFG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00001264 List of legal baudrate settings for this board.
1265
Tom Rini6a5dccc2022-11-16 13:10:41 -05001266- CFG_SYS_MEM_RESERVE_SECURE
York Sun1ef95cc2016-06-24 16:46:18 -07001267 Only implemented for ARMv8 for now.
Tom Rini6a5dccc2022-11-16 13:10:41 -05001268 If defined, the size of CFG_SYS_MEM_RESERVE_SECURE memory
York Sun5d286cd2015-12-04 11:57:07 -08001269 is substracted from total RAM and won't be reported to OS.
1270 This memory can be used as secure memory. A variable
York Sun1ef95cc2016-06-24 16:46:18 -07001271 gd->arch.secure_ram is used to track the location. In systems
York Sun5d286cd2015-12-04 11:57:07 -08001272 the RAM base is not zero, or RAM is divided into banks,
1273 this variable needs to be recalcuated to get the address.
1274
Tom Rinibb4dd962022-11-16 13:10:37 -05001275- CFG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00001276 Physical start address of SDRAM. _Must_ be 0 here.
1277
Tom Rini6a5dccc2022-11-16 13:10:41 -05001278- CFG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00001279 Physical start address of Flash memory.
1280
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001281- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00001282 Size of DRAM reserved for malloc() use.
1283
Tom Rini6a5dccc2022-11-16 13:10:41 -05001284- CFG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00001285 Maximum size of memory mapped by the startup code of
1286 the Linux kernel; all data that must be processed by
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02001287 the Linux kernel (bd_info, boot arguments, FDT blob if
1288 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day832d36e2013-09-16 07:15:45 -04001289 environment variable is defined and non-zero. In such case
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02001290 all data for the Linux kernel must be between "bootm_low"
Tom Rini6a5dccc2022-11-16 13:10:41 -05001291 and "bootm_low" + CFG_SYS_BOOTMAPSZ. The environment
Grant Likely26396382011-03-28 09:58:43 +00001292 variable "bootm_mapsize" will override the value of
Tom Rini6a5dccc2022-11-16 13:10:41 -05001293 CFG_SYS_BOOTMAPSZ. If CFG_SYS_BOOTMAPSZ is undefined,
Grant Likely26396382011-03-28 09:58:43 +00001294 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00001295
John Rigbyeea8e692010-10-13 13:57:35 -06001296- CONFIG_SYS_BOOT_GET_CMDLINE:
1297 Enables allocating and saving kernel cmdline in space between
1298 "bootm_low" and "bootm_low" + BOOTMAPSZ.
1299
1300- CONFIG_SYS_BOOT_GET_KBD:
1301 Enables allocating and saving a kernel copy of the bd_info in
1302 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
1303
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001304- CONFIG_SYS_FLASH_PROTECTION
wdenkdccbda02003-07-14 22:13:32 +00001305 If defined, hardware flash sectors protection is used
1306 instead of U-Boot software protection.
1307
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001308- CONFIG_SYS_FLASH_CFI:
wdenk4a5c8a72003-03-06 00:02:04 +00001309 Define if the flash driver uses extra elements in the
wdenk2cefd152004-02-08 22:55:38 +00001310 common flash structure for storing flash geometry.
1311
Jean-Christophe PLAGNIOL-VILLARD8d94c232008-08-13 01:40:42 +02001312- CONFIG_FLASH_CFI_DRIVER
wdenk2cefd152004-02-08 22:55:38 +00001313 This option also enables the building of the cfi_flash driver
1314 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00001315
Piotr Ziecik3e939e92008-11-17 15:57:58 +01001316- CONFIG_FLASH_CFI_MTD
1317 This option enables the building of the cfi_mtd driver
1318 in the drivers directory. The driver exports CFI flash
1319 to the MTD layer.
1320
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001321- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski183284f2008-04-03 13:36:02 +02001322 Use buffered writes to flash.
1323
Joe Hershberger71497d02012-12-11 22:16:31 -06001324- CONFIG_ENV_FLAGS_LIST_DEFAULT
Tom Rini0297e5f2022-12-04 10:03:40 -05001325- CFG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day832d36e2013-09-16 07:15:45 -04001326 Enable validation of the values given to environment variables when
Joe Hershberger71497d02012-12-11 22:16:31 -06001327 calling env set. Variables can be restricted to only decimal,
1328 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
1329 the variables can also be restricted to IP address or MAC address.
1330
1331 The format of the list is:
1332 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001333 access_attribute = [a|r|o|c]
1334 attributes = type_attribute[access_attribute]
Joe Hershberger71497d02012-12-11 22:16:31 -06001335 entry = variable_name[:attributes]
1336 list = entry[,list]
1337
1338 The type attributes are:
1339 s - String (default)
1340 d - Decimal
1341 x - Hexadecimal
1342 b - Boolean ([1yYtT|0nNfF])
1343 i - IP address
1344 m - MAC address
1345
Joe Hershberger6fe26c92012-12-11 22:16:34 -06001346 The access attributes are:
1347 a - Any (default)
1348 r - Read-only
1349 o - Write-once
1350 c - Change-default
1351
Joe Hershberger71497d02012-12-11 22:16:31 -06001352 - CONFIG_ENV_FLAGS_LIST_DEFAULT
1353 Define this to a list (string) to define the ".flags"
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001354 environment variable in the default or embedded environment.
Joe Hershberger71497d02012-12-11 22:16:31 -06001355
Tom Rini0297e5f2022-12-04 10:03:40 -05001356 - CFG_ENV_FLAGS_LIST_STATIC
Joe Hershberger71497d02012-12-11 22:16:31 -06001357 Define this to a list (string) to define validation that
1358 should be done if an entry is not found in the ".flags"
1359 environment variable. To override a setting in the static
1360 list, simply add an entry for the same variable name to the
1361 ".flags" variable.
1362
Joe Hershberger6db9fd42015-05-20 14:27:20 -05001363 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
1364 regular expression. This allows multiple variables to define the same
1365 flags without explicitly listing them for each variable.
1366
wdenkc6097192002-11-03 00:24:07 +00001367The following definitions that deal with the placement and management
1368of environment data (variable area); in general, we support the
1369following configurations:
1370
wdenkc6097192002-11-03 00:24:07 +00001371BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001372in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001373console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00001374U-Boot will hang.
1375
1376Please note that even with NVRAM we still use a copy of the
1377environment in RAM: we could work on NVRAM directly, but we want to
1378keep settings there always unmodified except somebody uses "saveenv"
1379to save the current settings.
1380
Liu Gang85bcd732012-03-08 00:33:20 +00001381BE CAREFUL! For some special cases, the local device can not use
1382"saveenv" command. For example, the local device will get the
Liu Gang357bf5a2012-08-09 05:10:01 +00001383environment stored in a remote NOR flash by SRIO or PCIE link,
1384but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang85bcd732012-03-08 00:33:20 +00001385
Guennadi Liakhovetskifad24442009-05-18 16:07:22 +02001386- CONFIG_NAND_ENV_DST
1387
1388 Defines address in RAM to which the nand_spl code should copy the
1389 environment. If redundant environment is used, it will be copied to
1390 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
1391
Bruce Adleredecc942007-11-02 13:15:42 -07001392Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00001393has been relocated to RAM and a RAM copy of the environment has been
Simon Glass64b723f2017-08-03 12:22:12 -06001394created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00001395until then to read environment variables.
1396
wdenk8dba0502003-03-31 16:34:49 +00001397The environment is protected by a CRC32 checksum. Before the monitor
1398is relocated into RAM, as a result of a bad CRC you will be working
1399with the compiled-in default environment - *silently*!!! [This is
1400necessary, because the first environment variable we need is the
1401"baudrate" setting for the console - if we have a bad CRC, we don't
1402have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00001403
1404Note: once the monitor has been relocated, then it will complain if
1405the default environment is used; a new CRC is computed as soon as you
wdenk8dba0502003-03-31 16:34:49 +00001406use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00001407
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001408- CONFIG_SYS_FAULT_MII_ADDR:
wdenk9c53f402003-10-15 23:53:47 +00001409 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00001410
Simon Glass28a9e332012-11-30 13:01:18 +00001411- CONFIG_DISPLAY_BOARDINFO
1412 Display information about the board that U-Boot is running on
1413 when U-Boot starts up. The board function checkboard() is called
1414 to do this.
1415
Simon Glasse8822012012-11-30 13:01:19 +00001416- CONFIG_DISPLAY_BOARDINFO_LATE
1417 Similar to the previous option, but display this information
1418 later, once stdio is running and output goes to the LCD, if
1419 present.
1420
wdenkc6097192002-11-03 00:24:07 +00001421Low Level (hardware related) configuration options:
wdenkc8434db2003-03-26 06:55:25 +00001422---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00001423
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001424- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00001425 Cache Line Size of the CPU.
1426
Timur Tabid8f341c2011-08-04 18:03:41 -05001427- CONFIG_SYS_CCSRBAR_DEFAULT:
1428 Default (power-on reset) physical address of CCSR on Freescale
1429 PowerPC SOCs.
1430
Tom Rini6a5dccc2022-11-16 13:10:41 -05001431- CFG_SYS_CCSRBAR:
Timur Tabid8f341c2011-08-04 18:03:41 -05001432 Virtual address of CCSR. On a 32-bit build, this is typically
1433 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
1434
Tom Rini6a5dccc2022-11-16 13:10:41 -05001435- CFG_SYS_CCSRBAR_PHYS:
Timur Tabid8f341c2011-08-04 18:03:41 -05001436 Physical address of CCSR. CCSR can be relocated to a new
1437 physical address, if desired. In this case, this macro should
Wolfgang Denk092ae952011-10-26 10:21:21 +00001438 be set to that address. Otherwise, it should be set to the
Timur Tabid8f341c2011-08-04 18:03:41 -05001439 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
1440 is typically relocated on 36-bit builds. It is recommended
1441 that this macro be defined via the _HIGH and _LOW macros:
1442
Tom Rini6a5dccc2022-11-16 13:10:41 -05001443 #define CFG_SYS_CCSRBAR_PHYS ((CFG_SYS_CCSRBAR_PHYS_HIGH
1444 * 1ull) << 32 | CFG_SYS_CCSRBAR_PHYS_LOW)
Timur Tabid8f341c2011-08-04 18:03:41 -05001445
Tom Rini6a5dccc2022-11-16 13:10:41 -05001446- CFG_SYS_CCSRBAR_PHYS_HIGH:
1447 Bits 33-36 of CFG_SYS_CCSRBAR_PHYS. This value is typically
Wolfgang Denkd590fb12011-10-07 09:58:21 +02001448 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabid8f341c2011-08-04 18:03:41 -05001449 used in assembly code, so it must not contain typecasts or
1450 integer size suffixes (e.g. "ULL").
1451
Tom Rini6a5dccc2022-11-16 13:10:41 -05001452- CFG_SYS_CCSRBAR_PHYS_LOW:
1453 Lower 32-bits of CFG_SYS_CCSRBAR_PHYS. This macro is
Timur Tabid8f341c2011-08-04 18:03:41 -05001454 used in assembly code, so it must not contain typecasts or
1455 integer size suffixes (e.g. "ULL").
1456
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001457- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenk07d7e6b2004-12-16 21:44:03 +00001458 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy069fa832017-07-06 10:23:22 +02001459 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00001460
Tom Rini6a5dccc2022-11-16 13:10:41 -05001461- CFG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00001462
wdenkeb20ad32003-09-05 23:19:14 +00001463 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00001464 initial data and stack; please note that this must be
1465 writable memory that is working WITHOUT special
1466 initialization, i. e. you CANNOT use normal RAM which
1467 will become available only after programming the
1468 memory controller and running certain initialization
1469 sequences.
1470
1471 U-Boot uses the following memory types:
Christophe Leroy069fa832017-07-06 10:23:22 +02001472 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00001473
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001474- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00001475
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001476- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00001477 SDRAM timing
1478
Kumar Gala8975d7a2010-12-30 12:09:53 -06001479- CONFIG_SYS_SRIOn_MEM_VIRT:
1480 Virtual Address of SRIO port 'n' memory region
1481
Simon Glass970b61e2019-11-14 12:57:09 -07001482- CONFIG_SYS_SRIOn_MEM_PHYxS:
Kumar Gala8975d7a2010-12-30 12:09:53 -06001483 Physical Address of SRIO port 'n' memory region
1484
1485- CONFIG_SYS_SRIOn_MEM_SIZE:
1486 Size of SRIO port 'n' memory region
1487
Fabio Estevamf17e8782013-04-11 09:35:34 +00001488- CONFIG_SYS_NAND_BUSWIDTH_16BIT
1489 Defined to tell the NAND controller that the NAND chip is using
1490 a 16 bit bus.
1491 Not all NAND drivers use this symbol.
Fabio Estevam417052b2013-04-11 09:35:35 +00001492 Example of drivers that use it:
Miquel Raynal1f1ae152018-08-16 17:30:07 +02001493 - drivers/mtd/nand/raw/ndfc.c
1494 - drivers/mtd/nand/raw/mxc_nand.c
Alex Watermancd6aae32011-05-19 15:08:36 -04001495
1496- CONFIG_SYS_NDFC_EBC0_CFG
1497 Sets the EBC0_CFG register for the NDFC. If not defined
1498 a default value will be used.
1499
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001500- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001501 If SPD EEPROM is on an I2C bus other than the first
1502 one, specify here. Note that the value must resolve
1503 to something your driver can deal with.
Ben Warren45657152006-09-07 16:50:54 -04001504
York Sunbd495cf2011-09-16 13:21:35 -07001505- CONFIG_FSL_DDR_INTERACTIVE
1506 Enable interactive DDR debugging. See doc/README.fsl-ddr.
1507
York Sun8ced0502015-01-06 13:18:55 -08001508- CONFIG_FSL_DDR_SYNC_REFRESH
1509 Enable sync of refresh for multiple controllers.
1510
York Sunb6a35f82015-03-19 09:30:28 -07001511- CONFIG_FSL_DDR_BIST
1512 Enable built-in memory test for Freescale DDR controllers.
1513
wdenk6203e402004-04-18 10:13:26 +00001514- CONFIG_RMII
1515 Enable RMII mode for all FECs.
1516 Note that this is a global option, we can't
1517 have one FEC in standard MII mode and another in RMII mode.
1518
wdenk20c98a62004-04-23 20:32:05 +00001519- CONFIG_CRC32_VERIFY
1520 Add a verify option to the crc32 command.
1521 The syntax is:
1522
1523 => crc32 -v <address> <count> <crc32>
1524
1525 Where address/count indicate a memory area
1526 and crc32 is the correct crc32 which the
1527 area should have.
1528
wdenk64519362004-07-11 17:40:54 +00001529- CONFIG_LOOPW
1530 Add the "loopw" memory command. This only takes effect if
Simon Glass92ffdee2017-08-04 16:34:27 -06001531 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk64519362004-07-11 17:40:54 +00001532
Joel Johnsondb5a97e2020-01-29 09:17:18 -07001533- CONFIG_CMD_MX_CYCLIC
stroesecc3af832004-12-16 18:46:55 +00001534 Add the "mdc" and "mwc" memory commands. These are cyclic
1535 "md/mw" commands.
1536 Examples:
1537
wdenk07d7e6b2004-12-16 21:44:03 +00001538 => mdc.b 10 4 500
stroesecc3af832004-12-16 18:46:55 +00001539 This command will print 4 bytes (10,11,12,13) each 500 ms.
1540
wdenk07d7e6b2004-12-16 21:44:03 +00001541 => mwc.l 100 12345678 10
stroesecc3af832004-12-16 18:46:55 +00001542 This command will write 12345678 to address 100 all 10 ms.
1543
wdenk07d7e6b2004-12-16 21:44:03 +00001544 This only takes effect if the memory commands are activated
Simon Glass92ffdee2017-08-04 16:34:27 -06001545 globally (CONFIG_CMD_MEMORY).
stroesecc3af832004-12-16 18:46:55 +00001546
Aneesh V552a3192011-07-13 05:11:07 +00001547- CONFIG_SPL_BUILD
Simon Glass489641f2023-11-18 14:04:50 -07001548 Set when the currently running compilation is for an artifact
1549 that will end up in one of the 'xPL' builds, i.e. SPL, TPL or
1550 VPL. Code that needs phase-specific behaviour can check this,
1551 or (where possible) use spl_phase() instead.
1552
1553 Note that CONFIG_SPL_BUILD *is* always defined when either
1554 of CONFIG_TPL_BUILD / CONFIG_VPL_BUILD is defined. This can be
1555 counter-intuitive and should perhaps be changed.
wdenk336b2bc2005-04-02 23:52:25 +00001556
Ying Zhang2d2e3b62013-08-16 15:16:15 +08001557- CONFIG_TPL_BUILD
Simon Glass489641f2023-11-18 14:04:50 -07001558 Set when the currently running compilation is for an artifact
1559 that will end up in the TPL build (as opposed to SPL, VPL or
1560 U-Boot proper). Code that needs phase-specific behaviour can
1561 check this, or (where possible) use spl_phase() instead.
1562
1563- CONFIG_VPL_BUILD
1564 Set when the currently running compilation is for an artifact
1565 that will end up in the VPL build (as opposed to the SPL, TPL
1566 or U-Boot proper). Code that needs phase-specific behaviour can
1567 check this, or (where possible) use spl_phase() instead.
Ying Zhang2d2e3b62013-08-16 15:16:15 +08001568
Simon Glass17dabf02013-02-24 17:33:14 +00001569- CONFIG_ARCH_MAP_SYSMEM
1570 Generally U-Boot (and in particular the md command) uses
1571 effective address. It is therefore not necessary to regard
1572 U-Boot address as virtual addresses that need to be translated
1573 to physical addresses. However, sandbox requires this, since
1574 it maintains its own little RAM buffer which contains all
1575 addressable memory. This option causes some memory accesses
1576 to be mapped through map_sysmem() / unmap_sysmem().
1577
Simon Glassbfb59802013-02-14 04:18:54 +00001578- CONFIG_X86_RESET_VECTOR
1579 If defined, the x86 reset vector code is included. This is not
1580 needed when U-Boot is running from Coreboot.
Gabe Black14f82462012-11-27 21:08:06 +00001581
Timur Tabi275f4bb2011-11-22 09:21:25 -06001582Freescale QE/FMAN Firmware Support:
1583-----------------------------------
1584
1585The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
1586loading of "firmware", which is encoded in the QE firmware binary format.
1587This firmware often needs to be loaded during U-Boot booting, so macros
1588are used to identify the storage device (NOR flash, SPI, etc) and the address
1589within that device.
1590
Zhao Qiang83a90842014-03-21 16:21:44 +08001591- CONFIG_SYS_FMAN_FW_ADDR
1592 The address in the storage device where the FMAN microcode is located. The
Tom Rinifa911f82019-05-12 07:59:12 -04001593 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Zhao Qiang83a90842014-03-21 16:21:44 +08001594 is also specified.
1595
1596- CONFIG_SYS_QE_FW_ADDR
1597 The address in the storage device where the QE microcode is located. The
Tom Rinifa911f82019-05-12 07:59:12 -04001598 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Timur Tabi275f4bb2011-11-22 09:21:25 -06001599 is also specified.
1600
1601- CONFIG_SYS_QE_FMAN_FW_LENGTH
1602 The maximum possible size of the firmware. The firmware binary format
1603 has a field that specifies the actual size of the firmware, but it
1604 might not be possible to read any part of the firmware unless some
1605 local storage is allocated to hold the entire firmware first.
1606
1607- CONFIG_SYS_QE_FMAN_FW_IN_NOR
1608 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
1609 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
1610 virtual address in NOR flash.
1611
1612- CONFIG_SYS_QE_FMAN_FW_IN_NAND
1613 Specifies that QE/FMAN firmware is located in NAND flash.
1614 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
1615
1616- CONFIG_SYS_QE_FMAN_FW_IN_MMC
1617 Specifies that QE/FMAN firmware is located on the primary SD/MMC
1618 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
1619
Liu Gang1e084582012-03-08 00:33:18 +00001620- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
1621 Specifies that QE/FMAN firmware is located in the remote (master)
1622 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gang357bf5a2012-08-09 05:10:01 +00001623 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
1624 window->master inbound window->master LAW->the ucode address in
1625 master's memory space.
Timur Tabi275f4bb2011-11-22 09:21:25 -06001626
J. German Rivera8ff14b72014-06-23 15:15:55 -07001627Freescale Layerscape Management Complex Firmware Support:
1628---------------------------------------------------------
1629The Freescale Layerscape Management Complex (MC) supports the loading of
1630"firmware".
1631This firmware often needs to be loaded during U-Boot booting, so macros
1632are used to identify the storage device (NOR flash, SPI, etc) and the address
1633within that device.
1634
1635- CONFIG_FSL_MC_ENET
1636 Enable the MC driver for Layerscape SoCs.
1637
Prabhakar Kushwaha853a9012015-06-02 10:55:52 +05301638Freescale Layerscape Debug Server Support:
1639-------------------------------------------
1640The Freescale Layerscape Debug Server Support supports the loading of
1641"Debug Server firmware" and triggering SP boot-rom.
1642This firmware often needs to be loaded during U-Boot booting.
1643
York Sun928b6812015-12-07 11:08:58 -08001644- CONFIG_SYS_MC_RSV_MEM_ALIGN
1645 Define alignment of reserved memory MC requires
Prabhakar Kushwaha853a9012015-06-02 10:55:52 +05301646
Paul Kocialkowski7b917022015-07-26 18:48:15 +02001647
wdenkc6097192002-11-03 00:24:07 +00001648Building the Software:
1649======================
1650
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001651Building U-Boot has been tested in several native build environments
1652and in many different cross environments. Of course we cannot support
1653all possibly existing versions of cross development tools in all
1654(potentially obsolete) versions. In case of tool chain problems we
Naoki Hayamae0cc1852020-10-08 13:17:16 +09001655recommend to use the ELDK (see https://www.denx.de/wiki/DULG/ELDK)
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001656which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00001657
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001658If you are not using a native environment, it is assumed that you
1659have GNU cross compiling tools available in your path. In this case,
1660you must set the environment variable CROSS_COMPILE in your shell.
1661Note that no changes to the Makefile or any other source files are
1662necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00001663
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001664 $ CROSS_COMPILE=ppc_4xx-
1665 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00001666
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001667U-Boot is intended to be simple to build. After installing the
1668sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00001669is done by typing:
1670
Holger Freyther7ba4e572014-08-04 09:26:05 +02001671 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00001672
Holger Freyther7ba4e572014-08-04 09:26:05 +02001673where "NAME_defconfig" is the name of one of the existing configu-
Heinrich Schuchardtd6e07af2020-02-24 18:36:30 +01001674rations; see configs/*_defconfig for supported names.
wdenk2f0812d2003-10-08 22:45:44 +00001675
Heinrich Schuchardtd6e07af2020-02-24 18:36:30 +01001676Note: for some boards special configuration names may exist; check if
wdenk6c59edc2004-05-03 20:45:30 +00001677 additional information is available from the board vendor; for
1678 instance, the TQM823L systems are available without (standard)
1679 or with LCD support. You can select such additional "features"
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001680 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00001681
Holger Freyther7ba4e572014-08-04 09:26:05 +02001682 make TQM823L_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00001683 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00001684
Holger Freyther7ba4e572014-08-04 09:26:05 +02001685 make TQM823L_LCD_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00001686 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00001687
wdenk6c59edc2004-05-03 20:45:30 +00001688 etc.
wdenkc6097192002-11-03 00:24:07 +00001689
wdenkc6097192002-11-03 00:24:07 +00001690
wdenk6c59edc2004-05-03 20:45:30 +00001691Finally, type "make all", and you should get some working U-Boot
1692images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00001693
wdenk6c59edc2004-05-03 20:45:30 +00001694- "u-boot.bin" is a raw binary image
1695- "u-boot" is an image in ELF binary format
1696- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00001697
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001698By default the build is performed locally and the objects are saved
1699in the source directory. One of the two methods can be used to change
1700this behavior and build U-Boot to some external directory:
1701
17021. Add O= to the make command line invocations:
1703
1704 make O=/tmp/build distclean
Holger Freyther7ba4e572014-08-04 09:26:05 +02001705 make O=/tmp/build NAME_defconfig
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001706 make O=/tmp/build all
1707
Timo Ketolac8c67602014-11-06 14:39:05 +020017082. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001709
Timo Ketolac8c67602014-11-06 14:39:05 +02001710 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001711 make distclean
Holger Freyther7ba4e572014-08-04 09:26:05 +02001712 make NAME_defconfig
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001713 make all
1714
Timo Ketolac8c67602014-11-06 14:39:05 +02001715Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001716variable.
1717
Daniel Schwierzeck88484422018-01-26 16:31:04 +01001718User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
1719setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
1720For example to treat all compiler warnings as errors:
1721
1722 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00001723
wdenk6c59edc2004-05-03 20:45:30 +00001724Please be aware that the Makefiles assume you are using GNU make, so
1725for instance on NetBSD you might need to use "gmake" instead of
1726native "make".
wdenkc6097192002-11-03 00:24:07 +00001727
wdenkc6097192002-11-03 00:24:07 +00001728
wdenk6c59edc2004-05-03 20:45:30 +00001729If the system board that you have is not listed, then you will need
1730to port U-Boot to your hardware platform. To do this, follow these
1731steps:
wdenkc6097192002-11-03 00:24:07 +00001732
Phil Sutterc77b4882015-12-25 14:41:18 +010017331. Create a new directory to hold your board specific code. Add any
wdenk6c59edc2004-05-03 20:45:30 +00001734 files you need. In your board directory, you will need at least
Phil Sutterc77b4882015-12-25 14:41:18 +01001735 the "Makefile" and a "<board>.c".
17362. Create a new configuration file "include/configs/<board>.h" for
1737 your board.
wdenk6c59edc2004-05-03 20:45:30 +000017383. If you're porting U-Boot to a new CPU, then also create a new
1739 directory to hold your CPU specific code. Add any files you need.
Holger Freyther7ba4e572014-08-04 09:26:05 +020017404. Run "make <board>_defconfig" with your new name.
wdenk6c59edc2004-05-03 20:45:30 +000017415. Type "make", and you should get a working "u-boot.srec" file
1742 to be installed on your target system.
17436. Debug and solve any problems that might arise.
1744 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00001745
wdenkc6097192002-11-03 00:24:07 +00001746
wdenk6c59edc2004-05-03 20:45:30 +00001747Testing of U-Boot Modifications, Ports to New Hardware, etc.:
1748==============================================================
wdenkc6097192002-11-03 00:24:07 +00001749
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001750If you have modified U-Boot sources (for instance added a new board
1751or support for new devices, a new CPU, etc.) you are expected to
wdenk6c59edc2004-05-03 20:45:30 +00001752provide feedback to the other developers. The feedback normally takes
Thomas Hebbfd37f242019-11-13 18:18:03 -08001753the form of a "patch", i.e. a context diff against a certain (latest
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001754official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00001755
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001756But before you submit such a patch, please verify that your modifi-
1757cation did not break existing code. At least make sure that *ALL* of
wdenk6c59edc2004-05-03 20:45:30 +00001758the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glassdc27def2016-07-27 20:33:08 -06001759just run the buildman script (tools/buildman/buildman), which will
1760configure and build U-Boot for ALL supported system. Be warned, this
1761will take a while. Please see the buildman README, or run 'buildman -H'
1762for documentation.
wdenkc6097192002-11-03 00:24:07 +00001763
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001764
wdenk6c59edc2004-05-03 20:45:30 +00001765See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00001766
wdenkc6097192002-11-03 00:24:07 +00001767
wdenk6c59edc2004-05-03 20:45:30 +00001768Monitor Commands - Overview:
1769============================
wdenkc6097192002-11-03 00:24:07 +00001770
wdenk6c59edc2004-05-03 20:45:30 +00001771go - start application at address 'addr'
1772run - run commands in an environment variable
1773bootm - boot application image from memory
1774bootp - boot image via network using BootP/TFTP protocol
Marek Vasutcf41a9b2012-03-14 21:52:45 +00001775bootz - boot zImage from memory
wdenk6c59edc2004-05-03 20:45:30 +00001776tftpboot- boot image via network using TFTP protocol
1777 and env variables "ipaddr" and "serverip"
1778 (and eventually "gatewayip")
Simon Glass6a398d22011-10-24 18:00:07 +00001779tftpput - upload a file via network using TFTP protocol
wdenk6c59edc2004-05-03 20:45:30 +00001780rarpboot- boot image via network using RARP/TFTP protocol
1781diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
1782loads - load S-Record file over serial line
1783loadb - load binary file over serial line (kermit mode)
Rui Miguel Silva433f15a2022-05-11 10:55:40 +01001784loadm - load binary blob from source address to destination address
wdenk6c59edc2004-05-03 20:45:30 +00001785md - memory display
1786mm - memory modify (auto-incrementing)
1787nm - memory modify (constant address)
1788mw - memory write (fill)
Simon Glass19038de2020-06-02 19:26:49 -06001789ms - memory search
wdenk6c59edc2004-05-03 20:45:30 +00001790cp - memory copy
1791cmp - memory compare
1792crc32 - checksum calculation
Peter Tyser469cde42009-04-18 22:34:03 -05001793i2c - I2C sub-system
wdenk6c59edc2004-05-03 20:45:30 +00001794sspi - SPI utility commands
1795base - print or set address offset
1796printenv- print environment variables
Pragnesh Patel1d5955f2020-12-22 11:30:05 +05301797pwm - control pwm channels
Linus Walleijbef39252023-02-01 00:16:13 +01001798seama - load SEAMA NAND image
wdenk6c59edc2004-05-03 20:45:30 +00001799setenv - set environment variables
1800saveenv - save environment variables to persistent storage
1801protect - enable or disable FLASH write protection
1802erase - erase FLASH memory
1803flinfo - print FLASH memory information
Karl O. Pinc4baf03d2012-08-03 05:57:21 +00001804nand - NAND memory operations (see doc/README.nand)
wdenk6c59edc2004-05-03 20:45:30 +00001805bdinfo - print Board Info structure
1806iminfo - print header information for application image
1807coninfo - print console devices and informations
1808ide - IDE sub-system
1809loop - infinite loop on address range
wdenk64519362004-07-11 17:40:54 +00001810loopw - infinite write loop on address range
wdenk6c59edc2004-05-03 20:45:30 +00001811mtest - simple RAM test
1812icache - enable or disable instruction cache
1813dcache - enable or disable data cache
1814reset - Perform RESET of the CPU
1815echo - echo args to console
1816version - print monitor version
1817help - print online help
1818? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00001819
wdenkc6097192002-11-03 00:24:07 +00001820
wdenk6c59edc2004-05-03 20:45:30 +00001821Monitor Commands - Detailed Description:
1822========================================
wdenkc6097192002-11-03 00:24:07 +00001823
wdenk6c59edc2004-05-03 20:45:30 +00001824TODO.
wdenkc6097192002-11-03 00:24:07 +00001825
wdenk6c59edc2004-05-03 20:45:30 +00001826For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00001827
1828
wdenk6c59edc2004-05-03 20:45:30 +00001829Note for Redundant Ethernet Interfaces:
1830=======================================
wdenkf4688a22003-05-28 08:06:31 +00001831
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001832Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk6c59edc2004-05-03 20:45:30 +00001833such configurations and is capable of automatic selection of a
1834"working" interface when needed. MAC assignment works as follows:
wdenkf4688a22003-05-28 08:06:31 +00001835
wdenk6c59edc2004-05-03 20:45:30 +00001836Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
1837MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
1838"eth1addr" (=>eth1), "eth2addr", ...
wdenkf4688a22003-05-28 08:06:31 +00001839
wdenk6c59edc2004-05-03 20:45:30 +00001840If the network interface stores some valid MAC address (for instance
1841in SROM), this is used as default address if there is NO correspon-
1842ding setting in the environment; if the corresponding environment
1843variable is set, this overrides the settings in the card; that means:
wdenkf4688a22003-05-28 08:06:31 +00001844
wdenk6c59edc2004-05-03 20:45:30 +00001845o If the SROM has a valid MAC address, and there is no address in the
1846 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00001847
wdenk6c59edc2004-05-03 20:45:30 +00001848o If there is no valid address in the SROM, and a definition in the
1849 environment exists, then the value from the environment variable is
1850 used.
wdenkc6097192002-11-03 00:24:07 +00001851
wdenk6c59edc2004-05-03 20:45:30 +00001852o If both the SROM and the environment contain a MAC address, and
1853 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00001854
wdenk6c59edc2004-05-03 20:45:30 +00001855o If both the SROM and the environment contain a MAC address, and the
1856 addresses differ, the value from the environment is used and a
1857 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00001858
wdenk6c59edc2004-05-03 20:45:30 +00001859o If neither SROM nor the environment contain a MAC address, an error
Joe Hershberger2dc2b5d2015-05-04 14:55:13 -05001860 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
1861 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00001862
Ben Warren6db991a2010-04-26 11:11:46 -07001863If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denk092ae952011-10-26 10:21:21 +00001864will be programmed into hardware as part of the initialization process. This
Ben Warren6db991a2010-04-26 11:11:46 -07001865may be skipped by setting the appropriate 'ethmacskip' environment variable.
1866The naming convention is as follows:
1867"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00001868
wdenk6c59edc2004-05-03 20:45:30 +00001869Image Formats:
1870==============
wdenkc6097192002-11-03 00:24:07 +00001871
Marian Balakowicz18710b82008-03-12 12:13:13 +01001872U-Boot is capable of booting (and performing other auxiliary operations on)
1873images in two formats:
1874
1875New uImage format (FIT)
1876-----------------------
1877
1878Flexible and powerful format based on Flattened Image Tree -- FIT (similar
1879to Flattened Device Tree). It allows the use of images with multiple
1880components (several kernels, ramdisks, etc.), with contents protected by
1881SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
1882
1883
1884Old uImage format
1885-----------------
1886
1887Old image format is based on binary files which can be basically anything,
1888preceded by a special header; see the definitions in include/image.h for
1889details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00001890
wdenk6c59edc2004-05-03 20:45:30 +00001891* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
1892 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyser56b8dd12008-09-08 14:56:49 -05001893 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
Thomas Huthc90d56a2021-11-13 18:13:50 +01001894 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, INTEGRITY).
Andy Shevchenko8cb5cdd2017-07-05 16:25:22 +03001895* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Tom Rini53320122022-04-06 09:21:25 -04001896 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
1897 Currently supported: ARM, Intel x86, MIPS, Nios II, PowerPC).
wdenk6c59edc2004-05-03 20:45:30 +00001898* Compression Type (uncompressed, gzip, bzip2)
1899* Load Address
1900* Entry Point
1901* Image Name
1902* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00001903
wdenk6c59edc2004-05-03 20:45:30 +00001904The header is marked by a special Magic Number, and both the header
1905and the data portions of the image are secured against corruption by
1906CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00001907
wdenkc6097192002-11-03 00:24:07 +00001908
wdenk6c59edc2004-05-03 20:45:30 +00001909Linux Support:
1910==============
wdenkc6097192002-11-03 00:24:07 +00001911
wdenk6c59edc2004-05-03 20:45:30 +00001912Although U-Boot should support any OS or standalone application
1913easily, the main focus has always been on Linux during the design of
1914U-Boot.
wdenkc6097192002-11-03 00:24:07 +00001915
wdenk6c59edc2004-05-03 20:45:30 +00001916U-Boot includes many features that so far have been part of some
1917special "boot loader" code within the Linux kernel. Also, any
1918"initrd" images to be used are no longer part of one big Linux image;
1919instead, kernel and "initrd" are separate images. This implementation
1920serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00001921
wdenk6c59edc2004-05-03 20:45:30 +00001922- the same features can be used for other OS or standalone
1923 applications (for instance: using compressed images to reduce the
1924 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00001925
wdenk6c59edc2004-05-03 20:45:30 +00001926- it becomes much easier to port new Linux kernel versions because
1927 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00001928
wdenk6c59edc2004-05-03 20:45:30 +00001929- the same Linux kernel image can now be used with different "initrd"
1930 images; of course this also means that different kernel images can
1931 be run with the same "initrd". This makes testing easier (you don't
1932 have to build a new "zImage.initrd" Linux image when you just
1933 change a file in your "initrd"). Also, a field-upgrade of the
1934 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00001935
wdenkc6097192002-11-03 00:24:07 +00001936
wdenk6c59edc2004-05-03 20:45:30 +00001937Linux HOWTO:
1938============
wdenkc6097192002-11-03 00:24:07 +00001939
wdenk6c59edc2004-05-03 20:45:30 +00001940Porting Linux to U-Boot based systems:
1941---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00001942
wdenk6c59edc2004-05-03 20:45:30 +00001943U-Boot cannot save you from doing all the necessary modifications to
1944configure the Linux device drivers for use with your target hardware
1945(no, we don't intend to provide a full virtual machine interface to
1946Linux :-).
wdenkc6097192002-11-03 00:24:07 +00001947
Stefan Roese88fbf932010-04-15 16:07:28 +02001948But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00001949
wdenk6c59edc2004-05-03 20:45:30 +00001950Just make sure your machine specific header file (for instance
1951include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg47167572008-09-07 20:18:27 +02001952Information structure as we define in include/asm-<arch>/u-boot.h,
1953and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001954as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00001955
Simon Glassd097e592014-06-11 23:29:46 -06001956Note that U-Boot now has a driver model, a unified model for drivers.
1957If you are adding a new driver, plumb it into driver model. If there
1958is no uclass available, you are encouraged to create one. See
1959doc/driver-model.
1960
wdenkc6097192002-11-03 00:24:07 +00001961
wdenk6c59edc2004-05-03 20:45:30 +00001962Configuring the Linux kernel:
1963-----------------------------
wdenkc6097192002-11-03 00:24:07 +00001964
wdenk6c59edc2004-05-03 20:45:30 +00001965No specific requirements for U-Boot. Make sure you have some root
1966device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00001967
wdenkc6097192002-11-03 00:24:07 +00001968
wdenk6c59edc2004-05-03 20:45:30 +00001969Building a Linux Image:
1970-----------------------
wdenkc6097192002-11-03 00:24:07 +00001971
wdenk6c59edc2004-05-03 20:45:30 +00001972With U-Boot, "normal" build targets like "zImage" or "bzImage" are
1973not used. If you use recent kernel source, a new build target
1974"uImage" will exist which automatically builds an image usable by
1975U-Boot. Most older kernels also have support for a "pImage" target,
1976which was introduced for our predecessor project PPCBoot and uses a
1977100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00001978
wdenk6c59edc2004-05-03 20:45:30 +00001979Example:
wdenkc6097192002-11-03 00:24:07 +00001980
Holger Freyther7ba4e572014-08-04 09:26:05 +02001981 make TQM850L_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00001982 make oldconfig
1983 make dep
1984 make uImage
wdenkc6097192002-11-03 00:24:07 +00001985
wdenk6c59edc2004-05-03 20:45:30 +00001986The "uImage" build target uses a special tool (in 'tools/mkimage') to
1987encapsulate a compressed Linux kernel image with header information,
1988CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00001989
wdenk6c59edc2004-05-03 20:45:30 +00001990* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00001991
wdenk6c59edc2004-05-03 20:45:30 +00001992* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00001993
wdenk6c59edc2004-05-03 20:45:30 +00001994 ${CROSS_COMPILE}-objcopy -O binary \
1995 -R .note -R .comment \
1996 -S vmlinux linux.bin
wdenk24ee89b2002-11-03 17:56:27 +00001997
wdenk6c59edc2004-05-03 20:45:30 +00001998* compress the binary image:
wdenk24ee89b2002-11-03 17:56:27 +00001999
wdenk6c59edc2004-05-03 20:45:30 +00002000 gzip -9 linux.bin
wdenk24ee89b2002-11-03 17:56:27 +00002001
wdenk6c59edc2004-05-03 20:45:30 +00002002* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00002003
wdenk6c59edc2004-05-03 20:45:30 +00002004 mkimage -A ppc -O linux -T kernel -C gzip \
2005 -a 0 -e 0 -n "Linux Kernel Image" \
2006 -d linux.bin.gz uImage
wdenkc6097192002-11-03 00:24:07 +00002007
wdenkc6097192002-11-03 00:24:07 +00002008
wdenk6c59edc2004-05-03 20:45:30 +00002009The "mkimage" tool can also be used to create ramdisk images for use
2010with U-Boot, either separated from the Linux kernel image, or
2011combined into one file. "mkimage" encapsulates the images with a 64
2012byte header containing information about target architecture,
2013operating system, image type, compression method, entry points, time
2014stamp, CRC32 checksums, etc.
wdenkc6097192002-11-03 00:24:07 +00002015
wdenk6c59edc2004-05-03 20:45:30 +00002016"mkimage" can be called in two ways: to verify existing images and
2017print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00002018
wdenk6c59edc2004-05-03 20:45:30 +00002019In the first form (with "-l" option) mkimage lists the information
2020contained in the header of an existing U-Boot image; this includes
2021checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00002022
wdenk6c59edc2004-05-03 20:45:30 +00002023 tools/mkimage -l image
2024 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00002025
wdenk6c59edc2004-05-03 20:45:30 +00002026The second form (with "-d" option) is used to build a U-Boot image
2027from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00002028
wdenk6c59edc2004-05-03 20:45:30 +00002029 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2030 -n name -d data_file image
2031 -A ==> set architecture to 'arch'
2032 -O ==> set operating system to 'os'
2033 -T ==> set image type to 'type'
2034 -C ==> set compression type 'comp'
2035 -a ==> set load address to 'addr' (hex)
2036 -e ==> set entry point to 'ep' (hex)
2037 -n ==> set image name to 'name'
2038 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00002039
wdenkcd914452004-05-29 16:53:29 +00002040Right now, all Linux kernels for PowerPC systems use the same load
2041address (0x00000000), but the entry point address depends on the
2042kernel version:
wdenkc6097192002-11-03 00:24:07 +00002043
wdenk6c59edc2004-05-03 20:45:30 +00002044- 2.2.x kernels have the entry point at 0x0000000C,
2045- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00002046
wdenk6c59edc2004-05-03 20:45:30 +00002047So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00002048
wdenk6c59edc2004-05-03 20:45:30 +00002049 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2050 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roese88fbf932010-04-15 16:07:28 +02002051 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk6c59edc2004-05-03 20:45:30 +00002052 > examples/uImage.TQM850L
2053 Image Name: 2.4.4 kernel for TQM850L
2054 Created: Wed Jul 19 02:34:59 2000
2055 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2056 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2057 Load Address: 0x00000000
2058 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002059
wdenk6c59edc2004-05-03 20:45:30 +00002060To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00002061
wdenk6c59edc2004-05-03 20:45:30 +00002062 -> tools/mkimage -l examples/uImage.TQM850L
2063 Image Name: 2.4.4 kernel for TQM850L
2064 Created: Wed Jul 19 02:34:59 2000
2065 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2066 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2067 Load Address: 0x00000000
2068 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002069
wdenk6c59edc2004-05-03 20:45:30 +00002070NOTE: for embedded systems where boot time is critical you can trade
2071speed for memory and install an UNCOMPRESSED image instead: this
2072needs more space in Flash, but boots much faster since it does not
2073need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00002074
Stefan Roese88fbf932010-04-15 16:07:28 +02002075 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk6c59edc2004-05-03 20:45:30 +00002076 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2077 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roese88fbf932010-04-15 16:07:28 +02002078 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk6c59edc2004-05-03 20:45:30 +00002079 > examples/uImage.TQM850L-uncompressed
2080 Image Name: 2.4.4 kernel for TQM850L
2081 Created: Wed Jul 19 02:34:59 2000
2082 Image Type: PowerPC Linux Kernel Image (uncompressed)
2083 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2084 Load Address: 0x00000000
2085 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002086
wdenkc6097192002-11-03 00:24:07 +00002087
wdenk6c59edc2004-05-03 20:45:30 +00002088Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2089when your kernel is intended to use an initial ramdisk:
wdenkc6097192002-11-03 00:24:07 +00002090
wdenk6c59edc2004-05-03 20:45:30 +00002091 -> tools/mkimage -n 'Simple Ramdisk Image' \
2092 > -A ppc -O linux -T ramdisk -C gzip \
2093 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2094 Image Name: Simple Ramdisk Image
2095 Created: Wed Jan 12 14:01:50 2000
2096 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2097 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2098 Load Address: 0x00000000
2099 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002100
Tyler Hicks791c7472020-10-26 10:40:24 -05002101The "dumpimage" tool can be used to disassemble or list the contents of images
2102built by mkimage. See dumpimage's help output (-h) for details.
wdenkc6097192002-11-03 00:24:07 +00002103
wdenk6c59edc2004-05-03 20:45:30 +00002104Installing a Linux Image:
2105-------------------------
wdenkc6097192002-11-03 00:24:07 +00002106
wdenk6c59edc2004-05-03 20:45:30 +00002107To downloading a U-Boot image over the serial (console) interface,
2108you must convert the image to S-Record format:
wdenkc6097192002-11-03 00:24:07 +00002109
wdenk6c59edc2004-05-03 20:45:30 +00002110 objcopy -I binary -O srec examples/image examples/image.srec
wdenkc6097192002-11-03 00:24:07 +00002111
wdenk6c59edc2004-05-03 20:45:30 +00002112The 'objcopy' does not understand the information in the U-Boot
2113image header, so the resulting S-Record file will be relative to
2114address 0x00000000. To load it to a given address, you need to
2115specify the target address as 'offset' parameter with the 'loads'
2116command.
wdenkc6097192002-11-03 00:24:07 +00002117
wdenk6c59edc2004-05-03 20:45:30 +00002118Example: install the image to address 0x40100000 (which on the
2119TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00002120
wdenk6c59edc2004-05-03 20:45:30 +00002121 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00002122
wdenk6c59edc2004-05-03 20:45:30 +00002123 .......... done
2124 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00002125
wdenk6c59edc2004-05-03 20:45:30 +00002126 => loads 40100000
2127 ## Ready for S-Record download ...
2128 ~>examples/image.srec
2129 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2130 ...
2131 15989 15990 15991 15992
2132 [file transfer complete]
2133 [connected]
2134 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002135
wdenkc6097192002-11-03 00:24:07 +00002136
wdenk6c59edc2004-05-03 20:45:30 +00002137You can check the success of the download using the 'iminfo' command;
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002138this includes a checksum verification so you can be sure no data
wdenk6c59edc2004-05-03 20:45:30 +00002139corruption happened:
wdenkc6097192002-11-03 00:24:07 +00002140
wdenk6c59edc2004-05-03 20:45:30 +00002141 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00002142
wdenk6c59edc2004-05-03 20:45:30 +00002143 ## Checking Image at 40100000 ...
2144 Image Name: 2.2.13 for initrd on TQM850L
2145 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2146 Data Size: 335725 Bytes = 327 kB = 0 MB
2147 Load Address: 00000000
2148 Entry Point: 0000000c
2149 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002150
2151
wdenk6c59edc2004-05-03 20:45:30 +00002152Boot Linux:
2153-----------
wdenkc6097192002-11-03 00:24:07 +00002154
wdenk6c59edc2004-05-03 20:45:30 +00002155The "bootm" command is used to boot an application that is stored in
2156memory (RAM or Flash). In case of a Linux kernel image, the contents
2157of the "bootargs" environment variable is passed to the kernel as
2158parameters. You can check and modify this variable using the
2159"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00002160
wdenkc6097192002-11-03 00:24:07 +00002161
wdenk6c59edc2004-05-03 20:45:30 +00002162 => printenv bootargs
2163 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00002164
wdenk6c59edc2004-05-03 20:45:30 +00002165 => 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 +00002166
wdenk6c59edc2004-05-03 20:45:30 +00002167 => printenv bootargs
2168 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 +00002169
wdenk6c59edc2004-05-03 20:45:30 +00002170 => bootm 40020000
2171 ## Booting Linux kernel at 40020000 ...
2172 Image Name: 2.2.13 for NFS on TQM850L
2173 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2174 Data Size: 381681 Bytes = 372 kB = 0 MB
2175 Load Address: 00000000
2176 Entry Point: 0000000c
2177 Verifying Checksum ... OK
2178 Uncompressing Kernel Image ... OK
2179 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
2180 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2181 time_init: decrementer frequency = 187500000/60
2182 Calibrating delay loop... 49.77 BogoMIPS
2183 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2184 ...
wdenkc6097192002-11-03 00:24:07 +00002185
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002186If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk6c59edc2004-05-03 20:45:30 +00002187the memory addresses of both the kernel and the initrd image (PPBCOOT
2188format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00002189
wdenk6c59edc2004-05-03 20:45:30 +00002190 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00002191
wdenk6c59edc2004-05-03 20:45:30 +00002192 ## Checking Image at 40100000 ...
2193 Image Name: 2.2.13 for initrd on TQM850L
2194 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2195 Data Size: 335725 Bytes = 327 kB = 0 MB
2196 Load Address: 00000000
2197 Entry Point: 0000000c
2198 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002199
wdenk6c59edc2004-05-03 20:45:30 +00002200 ## Checking Image at 40200000 ...
2201 Image Name: Simple Ramdisk Image
2202 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2203 Data Size: 566530 Bytes = 553 kB = 0 MB
2204 Load Address: 00000000
2205 Entry Point: 00000000
2206 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002207
wdenk6c59edc2004-05-03 20:45:30 +00002208 => bootm 40100000 40200000
2209 ## Booting Linux kernel at 40100000 ...
2210 Image Name: 2.2.13 for initrd on TQM850L
2211 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2212 Data Size: 335725 Bytes = 327 kB = 0 MB
2213 Load Address: 00000000
2214 Entry Point: 0000000c
2215 Verifying Checksum ... OK
2216 Uncompressing Kernel Image ... OK
2217 ## Loading RAMDisk Image at 40200000 ...
2218 Image Name: Simple Ramdisk Image
2219 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2220 Data Size: 566530 Bytes = 553 kB = 0 MB
2221 Load Address: 00000000
2222 Entry Point: 00000000
2223 Verifying Checksum ... OK
2224 Loading Ramdisk ... OK
2225 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
2226 Boot arguments: root=/dev/ram
2227 time_init: decrementer frequency = 187500000/60
2228 Calibrating delay loop... 49.77 BogoMIPS
2229 ...
2230 RAMDISK: Compressed image found at block 0
2231 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00002232
wdenk6c59edc2004-05-03 20:45:30 +00002233 bash#
wdenkc6097192002-11-03 00:24:07 +00002234
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002235Boot Linux and pass a flat device tree:
2236-----------
2237
2238First, U-Boot must be compiled with the appropriate defines. See the section
2239titled "Linux Kernel Interface" above for a more in depth explanation. The
2240following is an example of how to start a kernel and pass an updated
2241flat device tree:
2242
2243=> print oftaddr
2244oftaddr=0x300000
2245=> print oft
2246oft=oftrees/mpc8540ads.dtb
2247=> tftp $oftaddr $oft
2248Speed: 1000, full duplex
2249Using TSEC0 device
2250TFTP from server 192.168.1.1; our IP address is 192.168.1.101
2251Filename 'oftrees/mpc8540ads.dtb'.
2252Load address: 0x300000
2253Loading: #
2254done
2255Bytes transferred = 4106 (100a hex)
2256=> tftp $loadaddr $bootfile
2257Speed: 1000, full duplex
2258Using TSEC0 device
2259TFTP from server 192.168.1.1; our IP address is 192.168.1.2
2260Filename 'uImage'.
2261Load address: 0x200000
2262Loading:############
2263done
2264Bytes transferred = 1029407 (fb51f hex)
2265=> print loadaddr
2266loadaddr=200000
2267=> print oftaddr
2268oftaddr=0x300000
2269=> bootm $loadaddr - $oftaddr
2270## Booting image at 00200000 ...
Wolfgang Denk018147d2006-11-27 15:32:42 +01002271 Image Name: Linux-2.6.17-dirty
2272 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2273 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002274 Load Address: 00000000
Wolfgang Denk018147d2006-11-27 15:32:42 +01002275 Entry Point: 00000000
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002276 Verifying Checksum ... OK
2277 Uncompressing Kernel Image ... OK
2278Booting using flat device tree at 0x300000
2279Using MPC85xx ADS machine description
2280Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
2281[snip]
2282
2283
wdenk6c59edc2004-05-03 20:45:30 +00002284More About U-Boot Image Types:
2285------------------------------
wdenkc6097192002-11-03 00:24:07 +00002286
wdenk6c59edc2004-05-03 20:45:30 +00002287U-Boot supports the following image types:
wdenkc6097192002-11-03 00:24:07 +00002288
wdenk6c59edc2004-05-03 20:45:30 +00002289 "Standalone Programs" are directly runnable in the environment
2290 provided by U-Boot; it is expected that (if they behave
2291 well) you can continue to work in U-Boot after return from
2292 the Standalone Program.
2293 "OS Kernel Images" are usually images of some Embedded OS which
2294 will take over control completely. Usually these programs
2295 will install their own set of exception handlers, device
2296 drivers, set up the MMU, etc. - this means, that you cannot
2297 expect to re-enter U-Boot except by resetting the CPU.
2298 "RAMDisk Images" are more or less just data blocks, and their
2299 parameters (address, size) are passed to an OS kernel that is
2300 being started.
2301 "Multi-File Images" contain several images, typically an OS
2302 (Linux) kernel image and one or more data images like
2303 RAMDisks. This construct is useful for instance when you want
2304 to boot over the network using BOOTP etc., where the boot
2305 server provides just a single image file, but you want to get
2306 for instance an OS kernel and a RAMDisk image.
wdenkc6097192002-11-03 00:24:07 +00002307
wdenk6c59edc2004-05-03 20:45:30 +00002308 "Multi-File Images" start with a list of image sizes, each
2309 image size (in bytes) specified by an "uint32_t" in network
2310 byte order. This list is terminated by an "(uint32_t)0".
2311 Immediately after the terminating 0 follow the images, one by
2312 one, all aligned on "uint32_t" boundaries (size rounded up to
2313 a multiple of 4 bytes).
wdenkc6097192002-11-03 00:24:07 +00002314
wdenk6c59edc2004-05-03 20:45:30 +00002315 "Firmware Images" are binary images containing firmware (like
2316 U-Boot or FPGA images) which usually will be programmed to
2317 flash memory.
wdenk4fc95692003-02-28 00:49:47 +00002318
wdenk6c59edc2004-05-03 20:45:30 +00002319 "Script files" are command sequences that will be executed by
2320 U-Boot's command interpreter; this feature is especially
2321 useful when you configure U-Boot to use a real shell (hush)
2322 as command interpreter.
wdenk4fc95692003-02-28 00:49:47 +00002323
Marek Vasutcf41a9b2012-03-14 21:52:45 +00002324Booting the Linux zImage:
2325-------------------------
2326
2327On some platforms, it's possible to boot Linux zImage. This is done
2328using the "bootz" command. The syntax of "bootz" command is the same
2329as the syntax of "bootm" command.
2330
Tom Rini45f46d12013-05-16 11:40:11 -04002331Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut28850d02012-03-18 11:47:58 +00002332kernel with raw initrd images. The syntax is slightly different, the
2333address of the initrd must be augmented by it's size, in the following
2334format: "<initrd addres>:<initrd size>".
2335
stroeseb9c17c52003-04-04 15:53:41 +00002336
wdenk6c59edc2004-05-03 20:45:30 +00002337Standalone HOWTO:
2338=================
stroeseb9c17c52003-04-04 15:53:41 +00002339
wdenk6c59edc2004-05-03 20:45:30 +00002340One of the features of U-Boot is that you can dynamically load and
2341run "standalone" applications, which can use some resources of
2342U-Boot like console I/O functions or interrupt services.
stroeseb9c17c52003-04-04 15:53:41 +00002343
wdenk6c59edc2004-05-03 20:45:30 +00002344Two simple examples are included with the sources:
wdenk4fc95692003-02-28 00:49:47 +00002345
wdenk6c59edc2004-05-03 20:45:30 +00002346"Hello World" Demo:
2347-------------------
wdenkc6097192002-11-03 00:24:07 +00002348
wdenk6c59edc2004-05-03 20:45:30 +00002349'examples/hello_world.c' contains a small "Hello World" Demo
2350application; it is automatically compiled when you build U-Boot.
2351It's configured to run at address 0x00040004, so you can play with it
2352like that:
wdenkc6097192002-11-03 00:24:07 +00002353
wdenk6c59edc2004-05-03 20:45:30 +00002354 => loads
2355 ## Ready for S-Record download ...
2356 ~>examples/hello_world.srec
2357 1 2 3 4 5 6 7 8 9 10 11 ...
2358 [file transfer complete]
2359 [connected]
2360 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00002361
wdenk6c59edc2004-05-03 20:45:30 +00002362 => go 40004 Hello World! This is a test.
2363 ## Starting application at 0x00040004 ...
2364 Hello World
2365 argc = 7
2366 argv[0] = "40004"
2367 argv[1] = "Hello"
2368 argv[2] = "World!"
2369 argv[3] = "This"
2370 argv[4] = "is"
2371 argv[5] = "a"
2372 argv[6] = "test."
2373 argv[7] = "<NULL>"
2374 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00002375
wdenk6c59edc2004-05-03 20:45:30 +00002376 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00002377
wdenk6c59edc2004-05-03 20:45:30 +00002378Another example, which demonstrates how to register a CPM interrupt
2379handler with the U-Boot code, can be found in 'examples/timer.c'.
2380Here, a CPM timer is set up to generate an interrupt every second.
2381The interrupt service routine is trivial, just printing a '.'
2382character, but this is just a demo program. The application can be
2383controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00002384
wdenk6c59edc2004-05-03 20:45:30 +00002385 ? - print current values og the CPM Timer registers
2386 b - enable interrupts and start timer
2387 e - stop timer and disable interrupts
2388 q - quit application
wdenkc6097192002-11-03 00:24:07 +00002389
wdenk6c59edc2004-05-03 20:45:30 +00002390 => loads
2391 ## Ready for S-Record download ...
2392 ~>examples/timer.srec
2393 1 2 3 4 5 6 7 8 9 10 11 ...
2394 [file transfer complete]
2395 [connected]
2396 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00002397
wdenk6c59edc2004-05-03 20:45:30 +00002398 => go 40004
2399 ## Starting application at 0x00040004 ...
2400 TIMERS=0xfff00980
2401 Using timer 1
2402 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00002403
wdenk6c59edc2004-05-03 20:45:30 +00002404Hit 'b':
2405 [q, b, e, ?] Set interval 1000000 us
2406 Enabling timer
2407Hit '?':
2408 [q, b, e, ?] ........
2409 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2410Hit '?':
2411 [q, b, e, ?] .
2412 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2413Hit '?':
2414 [q, b, e, ?] .
2415 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2416Hit '?':
2417 [q, b, e, ?] .
2418 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2419Hit 'e':
2420 [q, b, e, ?] ...Stopping timer
2421Hit 'q':
2422 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00002423
wdenkc6097192002-11-03 00:24:07 +00002424
wdenk6c59edc2004-05-03 20:45:30 +00002425Implementation Internals:
2426=========================
wdenkc6097192002-11-03 00:24:07 +00002427
wdenk6c59edc2004-05-03 20:45:30 +00002428The following is not intended to be a complete description of every
2429implementation detail. However, it should help to understand the
2430inner workings of U-Boot and make it easier to port it to custom
2431hardware.
wdenkc6097192002-11-03 00:24:07 +00002432
wdenkc6097192002-11-03 00:24:07 +00002433
wdenk6c59edc2004-05-03 20:45:30 +00002434Initial Stack, Global Data:
2435---------------------------
wdenkc6097192002-11-03 00:24:07 +00002436
wdenk6c59edc2004-05-03 20:45:30 +00002437The implementation of U-Boot is complicated by the fact that U-Boot
2438starts running out of ROM (flash memory), usually without access to
2439system RAM (because the memory controller is not initialized yet).
2440This means that we don't have writable Data or BSS segments, and BSS
2441is not initialized as zero. To be able to get a C environment working
2442at all, we have to allocate at least a minimal stack. Implementation
2443options for this are defined and restricted by the CPU used: Some CPU
2444models provide on-chip memory (like the IMMR area on MPC8xx and
2445MPC826x processors), on others (parts of) the data cache can be
2446locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00002447
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002448 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01002449 U-Boot mailing list:
wdenkc6097192002-11-03 00:24:07 +00002450
wdenk6c59edc2004-05-03 20:45:30 +00002451 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2452 From: "Chris Hallinan" <clh@net1plus.com>
2453 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2454 ...
wdenkc6097192002-11-03 00:24:07 +00002455
wdenk6c59edc2004-05-03 20:45:30 +00002456 Correct me if I'm wrong, folks, but the way I understand it
2457 is this: Using DCACHE as initial RAM for Stack, etc, does not
2458 require any physical RAM backing up the cache. The cleverness
2459 is that the cache is being used as a temporary supply of
2460 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002461 beyond the scope of this list to explain the details, but you
wdenk6c59edc2004-05-03 20:45:30 +00002462 can see how this works by studying the cache architecture and
2463 operation in the architecture and processor-specific manuals.
wdenkc6097192002-11-03 00:24:07 +00002464
wdenk6c59edc2004-05-03 20:45:30 +00002465 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2466 is another option for the system designer to use as an
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002467 initial stack/RAM area prior to SDRAM being available. Either
wdenk6c59edc2004-05-03 20:45:30 +00002468 option should work for you. Using CS 4 should be fine if your
2469 board designers haven't used it for something that would
2470 cause you grief during the initial boot! It is frequently not
2471 used.
wdenkc6097192002-11-03 00:24:07 +00002472
Tom Rini6a5dccc2022-11-16 13:10:41 -05002473 CFG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk6c59edc2004-05-03 20:45:30 +00002474 with your processor/board/system design. The default value
2475 you will find in any recent u-boot distribution in
Stefan Roese3e1f1b32005-08-01 16:49:12 +02002476 walnut.h should work for you. I'd set it to a value larger
wdenk6c59edc2004-05-03 20:45:30 +00002477 than your SDRAM module. If you have a 64MB SDRAM module, set
2478 it above 400_0000. Just make sure your board has no resources
2479 that are supposed to respond to that address! That code in
2480 start.S has been around a while and should work as is when
2481 you get the config right.
wdenk4a5c8a72003-03-06 00:02:04 +00002482
wdenk6c59edc2004-05-03 20:45:30 +00002483 -Chris Hallinan
2484 DS4.COM, Inc.
wdenk4a5c8a72003-03-06 00:02:04 +00002485
wdenk6c59edc2004-05-03 20:45:30 +00002486It is essential to remember this, since it has some impact on the C
2487code for the initialization procedures:
wdenk4a5c8a72003-03-06 00:02:04 +00002488
wdenk6c59edc2004-05-03 20:45:30 +00002489* Initialized global data (data segment) is read-only. Do not attempt
2490 to write it.
wdenk4a5c8a72003-03-06 00:02:04 +00002491
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002492* Do not use any uninitialized global data (or implicitly initialized
wdenk6c59edc2004-05-03 20:45:30 +00002493 as zero data - BSS segment) at all - this is undefined, initiali-
2494 zation is performed later (when relocating to RAM).
wdenk4a5c8a72003-03-06 00:02:04 +00002495
wdenk6c59edc2004-05-03 20:45:30 +00002496* Stack space is very limited. Avoid big data buffers or things like
2497 that.
wdenk4a5c8a72003-03-06 00:02:04 +00002498
wdenk6c59edc2004-05-03 20:45:30 +00002499Having only the stack as writable memory limits means we cannot use
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002500normal global data to share information between the code. But it
wdenk6c59edc2004-05-03 20:45:30 +00002501turned out that the implementation of U-Boot can be greatly
2502simplified by making a global data structure (gd_t) available to all
2503functions. We could pass a pointer to this data as argument to _all_
2504functions, but this would bloat the code. Instead we use a feature of
2505the GCC compiler (Global Register Variables) to share the data: we
2506place a pointer (gd) to the global data into a register which we
2507reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00002508
wdenk6c59edc2004-05-03 20:45:30 +00002509When choosing a register for such a purpose we are restricted by the
2510relevant (E)ABI specifications for the current architecture, and by
2511GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00002512
wdenk6c59edc2004-05-03 20:45:30 +00002513For PowerPC, the following registers have specific use:
2514 R1: stack pointer
Wolfgang Denk69c09642008-02-14 22:43:22 +01002515 R2: reserved for system use
wdenk6c59edc2004-05-03 20:45:30 +00002516 R3-R4: parameter passing and return values
2517 R5-R10: parameter passing
2518 R13: small data area pointer
2519 R30: GOT pointer
2520 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00002521
Joakim Tjernlund693c0c12010-01-19 14:41:58 +01002522 (U-Boot also uses R12 as internal GOT pointer. r12
2523 is a volatile register so r12 needs to be reset when
2524 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00002525
Wolfgang Denk69c09642008-02-14 22:43:22 +01002526 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00002527
wdenk6c59edc2004-05-03 20:45:30 +00002528 Note: on PPC, we could use a static initializer (since the
2529 address of the global data structure is known at compile time),
2530 but it turned out that reserving a register results in somewhat
2531 smaller code - although the code savings are not that big (on
2532 average for all boards 752 bytes for the whole U-Boot image,
2533 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00002534
wdenk6c59edc2004-05-03 20:45:30 +00002535On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00002536
wdenk6c59edc2004-05-03 20:45:30 +00002537 R0: function argument word/integer result
2538 R1-R3: function argument word
Jeroen Hofsteea556aca2013-09-21 14:04:42 +02002539 R9: platform specific
2540 R10: stack limit (used only if stack checking is enabled)
wdenk6c59edc2004-05-03 20:45:30 +00002541 R11: argument (frame) pointer
2542 R12: temporary workspace
2543 R13: stack pointer
2544 R14: link register
2545 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00002546
Jeroen Hofsteea556aca2013-09-21 14:04:42 +02002547 ==> U-Boot will use R9 to hold a pointer to the global data
2548
2549 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00002550
Thomas Chou8fa38582010-05-21 11:08:03 +08002551On Nios II, the ABI is documented here:
Naoki Hayamae0cc1852020-10-08 13:17:16 +09002552 https://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
Thomas Chou8fa38582010-05-21 11:08:03 +08002553
2554 ==> U-Boot will use gp to hold a pointer to the global data
2555
2556 Note: on Nios II, we give "-G0" option to gcc and don't use gp
2557 to access small data sections, so gp is free.
2558
Rick Chend7e6f922017-12-26 13:55:59 +08002559On RISC-V, the following registers are used:
2560
2561 x0: hard-wired zero (zero)
2562 x1: return address (ra)
2563 x2: stack pointer (sp)
2564 x3: global pointer (gp)
2565 x4: thread pointer (tp)
2566 x5: link register (t0)
2567 x8: frame pointer (fp)
2568 x10-x11: arguments/return values (a0-1)
2569 x12-x17: arguments (a2-7)
2570 x28-31: temporaries (t3-6)
2571 pc: program counter (pc)
2572
2573 ==> U-Boot will use gp to hold a pointer to the global data
2574
wdenk6c59edc2004-05-03 20:45:30 +00002575Memory Management:
2576------------------
wdenkc6097192002-11-03 00:24:07 +00002577
wdenk6c59edc2004-05-03 20:45:30 +00002578U-Boot runs in system state and uses physical addresses, i.e. the
2579MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00002580
wdenk6c59edc2004-05-03 20:45:30 +00002581The available memory is mapped to fixed addresses using the memory
2582controller. In this process, a contiguous block is formed for each
2583memory type (Flash, SDRAM, SRAM), even when it consists of several
2584physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00002585
wdenk6c59edc2004-05-03 20:45:30 +00002586U-Boot is installed in the first 128 kB of the first Flash bank (on
2587TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
2588booting and sizing and initializing DRAM, the code relocates itself
2589to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002590memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk6c59edc2004-05-03 20:45:30 +00002591configuration setting]. Below that, a structure with global Board
2592Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00002593
wdenk6c59edc2004-05-03 20:45:30 +00002594Additionally, some exception handler code is copied to the low 8 kB
2595of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00002596
wdenk6c59edc2004-05-03 20:45:30 +00002597So a typical memory configuration with 16 MB of DRAM could look like
2598this:
wdenkc6097192002-11-03 00:24:07 +00002599
wdenk6c59edc2004-05-03 20:45:30 +00002600 0x0000 0000 Exception Vector code
2601 :
2602 0x0000 1FFF
2603 0x0000 2000 Free for Application Use
2604 :
2605 :
wdenkc6097192002-11-03 00:24:07 +00002606
wdenk6c59edc2004-05-03 20:45:30 +00002607 :
2608 :
2609 0x00FB FF20 Monitor Stack (Growing downward)
2610 0x00FB FFAC Board Info Data and permanent copy of global data
2611 0x00FC 0000 Malloc Arena
2612 :
2613 0x00FD FFFF
2614 0x00FE 0000 RAM Copy of Monitor Code
2615 ... eventually: LCD or video framebuffer
2616 ... eventually: pRAM (Protected RAM - unchanged by reset)
2617 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00002618
wdenkc6097192002-11-03 00:24:07 +00002619
wdenk6c59edc2004-05-03 20:45:30 +00002620System Initialization:
2621----------------------
wdenkc6097192002-11-03 00:24:07 +00002622
wdenk6c59edc2004-05-03 20:45:30 +00002623In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002624(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002625configuration for CS0# this is a mirror of the on board Flash memory.
wdenk6c59edc2004-05-03 20:45:30 +00002626To be able to re-map memory U-Boot then jumps to its link address.
2627To be able to implement the initialization code in C, a (small!)
2628initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher71cb3e92017-06-07 17:33:10 +02002629which provide such a feature like), or in a locked part of the data
2630cache. After that, U-Boot initializes the CPU core, the caches and
2631the SIU.
wdenkc6097192002-11-03 00:24:07 +00002632
wdenk6c59edc2004-05-03 20:45:30 +00002633Next, all (potentially) available memory banks are mapped using a
2634preliminary mapping. For example, we put them on 512 MB boundaries
2635(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
2636on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
2637programmed for SDRAM access. Using the temporary configuration, a
2638simple memory test is run that determines the size of the SDRAM
2639banks.
wdenkc6097192002-11-03 00:24:07 +00002640
wdenk6c59edc2004-05-03 20:45:30 +00002641When there is more than one SDRAM bank, and the banks are of
2642different size, the largest is mapped first. For equal size, the first
2643bank (CS2#) is mapped first. The first mapping is always for address
26440x00000000, with any additional banks following immediately to create
2645contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00002646
wdenk6c59edc2004-05-03 20:45:30 +00002647Then, the monitor installs itself at the upper end of the SDRAM area
2648and allocates memory for use by malloc() and for the global Board
2649Info data; also, the exception vector code is copied to the low RAM
2650pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00002651
wdenk6c59edc2004-05-03 20:45:30 +00002652Only after this relocation will you have a "normal" C environment;
2653until that you are restricted in several ways, mostly because you are
2654running from ROM, and because the code will have to be relocated to a
2655new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00002656
wdenkc6097192002-11-03 00:24:07 +00002657
Heinrich Schuchardtdf053fc2023-01-25 19:14:57 +01002658Contributing
2659============
wdenkcbc49a52005-05-03 14:12:25 +00002660
Heinrich Schuchardtdf053fc2023-01-25 19:14:57 +01002661The U-Boot projects depends on contributions from the user community.
2662If you want to participate, please, have a look at the 'General'
2663section of https://u-boot.readthedocs.io/en/latest/develop/index.html
2664where we describe coding standards and the patch submission process.