2 # (C) Copyright 2000 - 2012
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # See file CREDITS for list of people who contributed to this
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
57 Note: There is no CHANGELOG file in the actual U-Boot source tree;
58 it can be created dynamically from the Git log using:
66 In case you have questions about, problems with or contributions for
67 U-Boot you should send a message to the U-Boot mailing list at
68 <u-boot@lists.denx.de>. There is also an archive of previous traffic
69 on the mailing list - please search the archive before asking FAQ's.
70 Please see http://lists.denx.de/pipermail/u-boot and
71 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
74 Where to get source code:
75 =========================
77 The U-Boot source code is maintained in the git repository at
78 git://www.denx.de/git/u-boot.git ; you can browse it online at
79 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
81 The "snapshot" links on this page allow you to download tarballs of
82 any version you might be interested in. Official releases are also
83 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
86 Pre-built (and tested) images are available from
87 ftp://ftp.denx.de/pub/u-boot/images/
93 - start from 8xxrom sources
94 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
96 - make it easier to add custom boards
97 - make it possible to add other [PowerPC] CPUs
98 - extend functions, especially:
99 * Provide extended interface to Linux boot loader
102 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
103 - create ARMBoot project (http://sourceforge.net/projects/armboot)
104 - add other CPU families (starting with ARM)
105 - create U-Boot project (http://sourceforge.net/projects/u-boot)
106 - current project page: see http://www.denx.de/wiki/U-Boot
112 The "official" name of this project is "Das U-Boot". The spelling
113 "U-Boot" shall be used in all written text (documentation, comments
114 in source files etc.). Example:
116 This is the README file for the U-Boot project.
118 File names etc. shall be based on the string "u-boot". Examples:
120 include/asm-ppc/u-boot.h
122 #include <asm/u-boot.h>
124 Variable names, preprocessor constants etc. shall be either based on
125 the string "u_boot" or on "U_BOOT". Example:
127 U_BOOT_VERSION u_boot_logo
128 IH_OS_U_BOOT u_boot_hush_start
134 Starting with the release in October 2008, the names of the releases
135 were changed from numerical release numbers without deeper meaning
136 into a time stamp based numbering. Regular releases are identified by
137 names consisting of the calendar year and month of the release date.
138 Additional fields (if present) indicate release candidates or bug fix
139 releases in "stable" maintenance trees.
142 U-Boot v2009.11 - Release November 2009
143 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
144 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
150 /arch Architecture specific files
151 /arm Files generic to ARM architecture
152 /cpu CPU specific files
153 /arm720t Files specific to ARM 720 CPUs
154 /arm920t Files specific to ARM 920 CPUs
155 /at91 Files specific to Atmel AT91RM9200 CPU
156 /imx Files specific to Freescale MC9328 i.MX CPUs
157 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
158 /arm925t Files specific to ARM 925 CPUs
159 /arm926ejs Files specific to ARM 926 CPUs
160 /arm1136 Files specific to ARM 1136 CPUs
161 /ixp Files specific to Intel XScale IXP CPUs
162 /pxa Files specific to Intel XScale PXA CPUs
163 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
164 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
165 /lib Architecture specific library files
166 /avr32 Files generic to AVR32 architecture
167 /cpu CPU specific files
168 /lib Architecture specific library files
169 /blackfin Files generic to Analog Devices Blackfin architecture
170 /cpu CPU specific files
171 /lib Architecture specific library files
172 /x86 Files generic to x86 architecture
173 /cpu CPU specific files
174 /lib Architecture specific library files
175 /m68k Files generic to m68k architecture
176 /cpu CPU specific files
177 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
178 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
179 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
180 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
181 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
182 /lib Architecture specific library files
183 /microblaze Files generic to microblaze architecture
184 /cpu CPU specific files
185 /lib Architecture specific library files
186 /mips Files generic to MIPS architecture
187 /cpu CPU specific files
188 /mips32 Files specific to MIPS32 CPUs
189 /xburst Files specific to Ingenic XBurst CPUs
190 /lib Architecture specific library files
191 /nds32 Files generic to NDS32 architecture
192 /cpu CPU specific files
193 /n1213 Files specific to Andes Technology N1213 CPUs
194 /lib Architecture specific library files
195 /nios2 Files generic to Altera NIOS2 architecture
196 /cpu CPU specific files
197 /lib Architecture specific library files
198 /powerpc Files generic to PowerPC architecture
199 /cpu CPU specific files
200 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
201 /mpc5xx Files specific to Freescale MPC5xx CPUs
202 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
203 /mpc8xx Files specific to Freescale MPC8xx CPUs
204 /mpc8220 Files specific to Freescale MPC8220 CPUs
205 /mpc824x Files specific to Freescale MPC824x CPUs
206 /mpc8260 Files specific to Freescale MPC8260 CPUs
207 /mpc85xx Files specific to Freescale MPC85xx CPUs
208 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
209 /lib Architecture specific library files
210 /sh Files generic to SH architecture
211 /cpu CPU specific files
212 /sh2 Files specific to sh2 CPUs
213 /sh3 Files specific to sh3 CPUs
214 /sh4 Files specific to sh4 CPUs
215 /lib Architecture specific library files
216 /sparc Files generic to SPARC architecture
217 /cpu CPU specific files
218 /leon2 Files specific to Gaisler LEON2 SPARC CPU
219 /leon3 Files specific to Gaisler LEON3 SPARC CPU
220 /lib Architecture specific library files
221 /api Machine/arch independent API for external apps
222 /board Board dependent files
223 /common Misc architecture independent functions
224 /disk Code for disk drive partition handling
225 /doc Documentation (don't expect too much)
226 /drivers Commonly used device drivers
227 /examples Example code for standalone applications, etc.
228 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
229 /include Header Files
230 /lib Files generic to all architectures
231 /libfdt Library files to support flattened device trees
232 /lzma Library files to support LZMA decompression
233 /lzo Library files to support LZO decompression
235 /post Power On Self Test
236 /rtc Real Time Clock drivers
237 /tools Tools to build S-Record or U-Boot images, etc.
239 Software Configuration:
240 =======================
242 Configuration is usually done using C preprocessor defines; the
243 rationale behind that is to avoid dead code whenever possible.
245 There are two classes of configuration variables:
247 * Configuration _OPTIONS_:
248 These are selectable by the user and have names beginning with
251 * Configuration _SETTINGS_:
252 These depend on the hardware etc. and should not be meddled with if
253 you don't know what you're doing; they have names beginning with
256 Later we will add a configuration tool - probably similar to or even
257 identical to what's used for the Linux kernel. Right now, we have to
258 do the configuration by hand, which means creating some symbolic
259 links and editing some configuration files. We use the TQM8xxL boards
263 Selection of Processor Architecture and Board Type:
264 ---------------------------------------------------
266 For all supported boards there are ready-to-use default
267 configurations available; just type "make <board_name>_config".
269 Example: For a TQM823L module type:
274 For the Cogent platform, you need to specify the CPU type as well;
275 e.g. "make cogent_mpc8xx_config". And also configure the cogent
276 directory according to the instructions in cogent/README.
279 Configuration Options:
280 ----------------------
282 Configuration depends on the combination of board and CPU type; all
283 such information is kept in a configuration file
284 "include/configs/<board_name>.h".
286 Example: For a TQM823L module, all configuration settings are in
287 "include/configs/TQM823L.h".
290 Many of the options are named exactly as the corresponding Linux
291 kernel configuration options. The intention is to make it easier to
292 build a config tool - later.
295 The following options need to be configured:
297 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
299 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
301 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
302 Define exactly one, e.g. CONFIG_ATSTK1002
304 - CPU Module Type: (if CONFIG_COGENT is defined)
305 Define exactly one of
307 --- FIXME --- not tested yet:
308 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
309 CONFIG_CMA287_23, CONFIG_CMA287_50
311 - Motherboard Type: (if CONFIG_COGENT is defined)
312 Define exactly one of
313 CONFIG_CMA101, CONFIG_CMA102
315 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
316 Define one or more of
319 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
320 Define one or more of
321 CONFIG_LCD_HEARTBEAT - update a character position on
322 the LCD display every second with
325 - Board flavour: (if CONFIG_MPC8260ADS is defined)
328 CONFIG_SYS_8260ADS - original MPC8260ADS
329 CONFIG_SYS_8266ADS - MPC8266ADS
330 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
331 CONFIG_SYS_8272ADS - MPC8272ADS
333 - Marvell Family Member
334 CONFIG_SYS_MVFS - define it if you want to enable
335 multiple fs option at one time
336 for marvell soc family
338 - MPC824X Family Member (if CONFIG_MPC824X is defined)
339 Define exactly one of
340 CONFIG_MPC8240, CONFIG_MPC8245
342 - 8xx CPU Options: (if using an MPC8xx CPU)
343 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
344 get_gclk_freq() cannot work
345 e.g. if there is no 32KHz
346 reference PIT/RTC clock
347 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
350 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
351 CONFIG_SYS_8xx_CPUCLK_MIN
352 CONFIG_SYS_8xx_CPUCLK_MAX
353 CONFIG_8xx_CPUCLK_DEFAULT
354 See doc/README.MPC866
356 CONFIG_SYS_MEASURE_CPUCLK
358 Define this to measure the actual CPU clock instead
359 of relying on the correctness of the configured
360 values. Mostly useful for board bringup to make sure
361 the PLL is locked at the intended frequency. Note
362 that this requires a (stable) reference clock (32 kHz
363 RTC clock or CONFIG_SYS_8XX_XIN)
365 CONFIG_SYS_DELAYED_ICACHE
367 Define this option if you want to enable the
368 ICache only when Code runs from RAM.
373 Specifies that the core is a 64-bit PowerPC implementation (implements
374 the "64" category of the Power ISA). This is necessary for ePAPR
375 compliance, among other possible reasons.
377 CONFIG_SYS_FSL_TBCLK_DIV
379 Defines the core time base clock divider ratio compared to the
380 system clock. On most PQ3 devices this is 8, on newer QorIQ
381 devices it can be 16 or 32. The ratio varies from SoC to Soc.
383 CONFIG_SYS_FSL_PCIE_COMPAT
385 Defines the string to utilize when trying to match PCIe device
386 tree nodes for the given platform.
388 CONFIG_SYS_PPC_E500_DEBUG_TLB
390 Enables a temporary TLB entry to be used during boot to work
391 around limitations in e500v1 and e500v2 external debugger
392 support. This reduces the portions of the boot code where
393 breakpoints and single stepping do not work. The value of this
394 symbol should be set to the TLB1 entry to be used for this
397 CONFIG_SYS_FSL_ERRATUM_A004510
399 Enables a workaround for erratum A004510. If set,
400 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
401 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
403 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
404 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
406 Defines one or two SoC revisions (low 8 bits of SVR)
407 for which the A004510 workaround should be applied.
409 The rest of SVR is either not relevant to the decision
410 of whether the erratum is present (e.g. p2040 versus
411 p2041) or is implied by the build target, which controls
412 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
414 See Freescale App Note 4493 for more information about
417 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
419 This is the value to write into CCSR offset 0x18600
420 according to the A004510 workaround.
422 - Generic CPU options:
423 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
425 Defines the endianess of the CPU. Implementation of those
426 values is arch specific.
428 - Intel Monahans options:
429 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
431 Defines the Monahans run mode to oscillator
432 ratio. Valid values are 8, 16, 24, 31. The core
433 frequency is this value multiplied by 13 MHz.
435 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
437 Defines the Monahans turbo mode to oscillator
438 ratio. Valid values are 1 (default if undefined) and
439 2. The core frequency as calculated above is multiplied
443 CONFIG_SYS_INIT_SP_OFFSET
445 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
446 pointer. This is needed for the temporary stack before
449 CONFIG_SYS_MIPS_CACHE_MODE
451 Cache operation mode for the MIPS CPU.
452 See also arch/mips/include/asm/mipsregs.h.
454 CONF_CM_CACHABLE_NO_WA
457 CONF_CM_CACHABLE_NONCOHERENT
461 CONF_CM_CACHABLE_ACCELERATED
463 CONFIG_SYS_XWAY_EBU_BOOTCFG
465 Special option for Lantiq XWAY SoCs for booting from NOR flash.
466 See also arch/mips/cpu/mips32/start.S.
468 CONFIG_XWAY_SWAP_BYTES
470 Enable compilation of tools/xway-swap-bytes needed for Lantiq
471 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
472 be swapped if a flash programmer is used.
475 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
477 Select high exception vectors of the ARM core, e.g., do not
478 clear the V bit of the c1 register of CP15.
480 CONFIG_SYS_THUMB_BUILD
482 Use this flag to build U-Boot using the Thumb instruction
483 set for ARM architectures. Thumb instruction set provides
484 better code density. For ARM architectures that support
485 Thumb2 this flag will result in Thumb2 code generated by
488 - Linux Kernel Interface:
491 U-Boot stores all clock information in Hz
492 internally. For binary compatibility with older Linux
493 kernels (which expect the clocks passed in the
494 bd_info data to be in MHz) the environment variable
495 "clocks_in_mhz" can be defined so that U-Boot
496 converts clock data to MHZ before passing it to the
498 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
499 "clocks_in_mhz=1" is automatically included in the
502 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
504 When transferring memsize parameter to linux, some versions
505 expect it to be in bytes, others in MB.
506 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
510 New kernel versions are expecting firmware settings to be
511 passed using flattened device trees (based on open firmware
515 * New libfdt-based support
516 * Adds the "fdt" command
517 * The bootm command automatically updates the fdt
519 OF_CPU - The proper name of the cpus node (only required for
520 MPC512X and MPC5xxx based boards).
521 OF_SOC - The proper name of the soc node (only required for
522 MPC512X and MPC5xxx based boards).
523 OF_TBCLK - The timebase frequency.
524 OF_STDOUT_PATH - The path to the console device
526 boards with QUICC Engines require OF_QE to set UCC MAC
529 CONFIG_OF_BOARD_SETUP
531 Board code has addition modification that it wants to make
532 to the flat device tree before handing it off to the kernel
536 This define fills in the correct boot CPU in the boot
537 param header, the default value is zero if undefined.
541 U-Boot can detect if an IDE device is present or not.
542 If not, and this new config option is activated, U-Boot
543 removes the ATA node from the DTS before booting Linux,
544 so the Linux IDE driver does not probe the device and
545 crash. This is needed for buggy hardware (uc101) where
546 no pull down resistor is connected to the signal IDE5V_DD7.
548 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
550 This setting is mandatory for all boards that have only one
551 machine type and must be used to specify the machine type
552 number as it appears in the ARM machine registry
553 (see http://www.arm.linux.org.uk/developer/machines/).
554 Only boards that have multiple machine types supported
555 in a single configuration file and the machine type is
556 runtime discoverable, do not have to use this setting.
558 - vxWorks boot parameters:
560 bootvx constructs a valid bootline using the following
561 environments variables: bootfile, ipaddr, serverip, hostname.
562 It loads the vxWorks image pointed bootfile.
564 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
565 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
566 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
567 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
569 CONFIG_SYS_VXWORKS_ADD_PARAMS
571 Add it at the end of the bootline. E.g "u=username pw=secret"
573 Note: If a "bootargs" environment is defined, it will overwride
574 the defaults discussed just above.
576 - Cache Configuration:
577 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
578 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
579 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
581 - Cache Configuration for ARM:
582 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
584 CONFIG_SYS_PL310_BASE - Physical base address of PL310
585 controller register space
590 Define this if you want support for Amba PrimeCell PL010 UARTs.
594 Define this if you want support for Amba PrimeCell PL011 UARTs.
598 If you have Amba PrimeCell PL011 UARTs, set this variable to
599 the clock speed of the UARTs.
603 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
604 define this to a list of base addresses for each (supported)
605 port. See e.g. include/configs/versatile.h
607 CONFIG_PL011_SERIAL_RLCR
609 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
610 have separate receive and transmit line control registers. Set
611 this variable to initialize the extra register.
613 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
615 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
616 boot loader that has already initialized the UART. Define this
617 variable to flush the UART at init time.
621 Depending on board, define exactly one serial port
622 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
623 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
624 console by defining CONFIG_8xx_CONS_NONE
626 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
627 port routines must be defined elsewhere
628 (i.e. serial_init(), serial_getc(), ...)
631 Enables console device for a color framebuffer. Needs following
632 defines (cf. smiLynxEM, i8042)
633 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
635 VIDEO_HW_RECTFILL graphic chip supports
638 VIDEO_HW_BITBLT graphic chip supports
639 bit-blit (cf. smiLynxEM)
640 VIDEO_VISIBLE_COLS visible pixel columns
642 VIDEO_VISIBLE_ROWS visible pixel rows
643 VIDEO_PIXEL_SIZE bytes per pixel
644 VIDEO_DATA_FORMAT graphic data format
645 (0-5, cf. cfb_console.c)
646 VIDEO_FB_ADRS framebuffer address
647 VIDEO_KBD_INIT_FCT keyboard int fct
648 (i.e. i8042_kbd_init())
649 VIDEO_TSTC_FCT test char fct
651 VIDEO_GETC_FCT get char fct
653 CONFIG_CONSOLE_CURSOR cursor drawing on/off
654 (requires blink timer
656 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
657 CONFIG_CONSOLE_TIME display time/date info in
659 (requires CONFIG_CMD_DATE)
660 CONFIG_VIDEO_LOGO display Linux logo in
662 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
663 linux_logo.h for logo.
664 Requires CONFIG_VIDEO_LOGO
665 CONFIG_CONSOLE_EXTRA_INFO
666 additional board info beside
669 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
670 a limited number of ANSI escape sequences (cursor control,
671 erase functions and limited graphics rendition control).
673 When CONFIG_CFB_CONSOLE is defined, video console is
674 default i/o. Serial console can be forced with
675 environment 'console=serial'.
677 When CONFIG_SILENT_CONSOLE is defined, all console
678 messages (by U-Boot and Linux!) can be silenced with
679 the "silent" environment variable. See
680 doc/README.silent for more information.
683 CONFIG_BAUDRATE - in bps
684 Select one of the baudrates listed in
685 CONFIG_SYS_BAUDRATE_TABLE, see below.
686 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
688 - Console Rx buffer length
689 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
690 the maximum receive buffer length for the SMC.
691 This option is actual only for 82xx and 8xx possible.
692 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
693 must be defined, to setup the maximum idle timeout for
696 - Pre-Console Buffer:
697 Prior to the console being initialised (i.e. serial UART
698 initialised etc) all console output is silently discarded.
699 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
700 buffer any console messages prior to the console being
701 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
702 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
703 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
704 bytes are output before the console is initialised, the
705 earlier bytes are discarded.
707 'Sane' compilers will generate smaller code if
708 CONFIG_PRE_CON_BUF_SZ is a power of 2
710 - Safe printf() functions
711 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
712 the printf() functions. These are defined in
713 include/vsprintf.h and include snprintf(), vsnprintf() and
714 so on. Code size increase is approximately 300-500 bytes.
715 If this option is not given then these functions will
716 silently discard their buffer size argument - this means
717 you are not getting any overflow checking in this case.
719 - Boot Delay: CONFIG_BOOTDELAY - in seconds
720 Delay before automatically booting the default image;
721 set to -1 to disable autoboot.
722 set to -2 to autoboot with no delay and not check for abort
723 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
725 See doc/README.autoboot for these options that
726 work with CONFIG_BOOTDELAY. None are required.
727 CONFIG_BOOT_RETRY_TIME
728 CONFIG_BOOT_RETRY_MIN
729 CONFIG_AUTOBOOT_KEYED
730 CONFIG_AUTOBOOT_PROMPT
731 CONFIG_AUTOBOOT_DELAY_STR
732 CONFIG_AUTOBOOT_STOP_STR
733 CONFIG_AUTOBOOT_DELAY_STR2
734 CONFIG_AUTOBOOT_STOP_STR2
735 CONFIG_ZERO_BOOTDELAY_CHECK
736 CONFIG_RESET_TO_RETRY
740 Only needed when CONFIG_BOOTDELAY is enabled;
741 define a command string that is automatically executed
742 when no character is read on the console interface
743 within "Boot Delay" after reset.
746 This can be used to pass arguments to the bootm
747 command. The value of CONFIG_BOOTARGS goes into the
748 environment value "bootargs".
750 CONFIG_RAMBOOT and CONFIG_NFSBOOT
751 The value of these goes into the environment as
752 "ramboot" and "nfsboot" respectively, and can be used
753 as a convenience, when switching between booting from
759 When this option is #defined, the existence of the
760 environment variable "preboot" will be checked
761 immediately before starting the CONFIG_BOOTDELAY
762 countdown and/or running the auto-boot command resp.
763 entering interactive mode.
765 This feature is especially useful when "preboot" is
766 automatically generated or modified. For an example
767 see the LWMON board specific code: here "preboot" is
768 modified when the user holds down a certain
769 combination of keys on the (special) keyboard when
772 - Serial Download Echo Mode:
774 If defined to 1, all characters received during a
775 serial download (using the "loads" command) are
776 echoed back. This might be needed by some terminal
777 emulations (like "cu"), but may as well just take
778 time on others. This setting #define's the initial
779 value of the "loads_echo" environment variable.
781 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
783 Select one of the baudrates listed in
784 CONFIG_SYS_BAUDRATE_TABLE, see below.
787 Monitor commands can be included or excluded
788 from the build by using the #include files
789 <config_cmd_all.h> and #undef'ing unwanted
790 commands, or using <config_cmd_default.h>
791 and augmenting with additional #define's
794 The default command configuration includes all commands
795 except those marked below with a "*".
797 CONFIG_CMD_ASKENV * ask for env variable
798 CONFIG_CMD_BDI bdinfo
799 CONFIG_CMD_BEDBUG * Include BedBug Debugger
800 CONFIG_CMD_BMP * BMP support
801 CONFIG_CMD_BSP * Board specific commands
802 CONFIG_CMD_BOOTD bootd
803 CONFIG_CMD_CACHE * icache, dcache
804 CONFIG_CMD_CONSOLE coninfo
805 CONFIG_CMD_CRC32 * crc32
806 CONFIG_CMD_DATE * support for RTC, date/time...
807 CONFIG_CMD_DHCP * DHCP support
808 CONFIG_CMD_DIAG * Diagnostics
809 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
810 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
811 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
812 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
813 CONFIG_CMD_DTT * Digital Therm and Thermostat
814 CONFIG_CMD_ECHO echo arguments
815 CONFIG_CMD_EDITENV edit env variable
816 CONFIG_CMD_EEPROM * EEPROM read/write support
817 CONFIG_CMD_ELF * bootelf, bootvx
818 CONFIG_CMD_EXPORTENV * export the environment
819 CONFIG_CMD_EXT2 * ext2 command support
820 CONFIG_CMD_EXT4 * ext4 command support
821 CONFIG_CMD_SAVEENV saveenv
822 CONFIG_CMD_FDC * Floppy Disk Support
823 CONFIG_CMD_FAT * FAT command support
824 CONFIG_CMD_FDOS * Dos diskette Support
825 CONFIG_CMD_FLASH flinfo, erase, protect
826 CONFIG_CMD_FPGA FPGA device initialization support
827 CONFIG_CMD_GETTIME * Get time since boot
828 CONFIG_CMD_GO * the 'go' command (exec code)
829 CONFIG_CMD_GREPENV * search environment
830 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
831 CONFIG_CMD_I2C * I2C serial bus support
832 CONFIG_CMD_IDE * IDE harddisk support
833 CONFIG_CMD_IMI iminfo
834 CONFIG_CMD_IMLS List all found images
835 CONFIG_CMD_IMMAP * IMMR dump support
836 CONFIG_CMD_IMPORTENV * import an environment
837 CONFIG_CMD_INI * import data from an ini file into the env
838 CONFIG_CMD_IRQ * irqinfo
839 CONFIG_CMD_ITEST Integer/string test of 2 values
840 CONFIG_CMD_JFFS2 * JFFS2 Support
841 CONFIG_CMD_KGDB * kgdb
842 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
843 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
845 CONFIG_CMD_LOADB loadb
846 CONFIG_CMD_LOADS loads
847 CONFIG_CMD_MD5SUM print md5 message digest
848 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
849 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
851 CONFIG_CMD_MISC Misc functions like sleep etc
852 CONFIG_CMD_MMC * MMC memory mapped support
853 CONFIG_CMD_MII * MII utility commands
854 CONFIG_CMD_MTDPARTS * MTD partition support
855 CONFIG_CMD_NAND * NAND support
856 CONFIG_CMD_NET bootp, tftpboot, rarpboot
857 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
858 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
859 CONFIG_CMD_PCI * pciinfo
860 CONFIG_CMD_PCMCIA * PCMCIA support
861 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
863 CONFIG_CMD_PORTIO * Port I/O
864 CONFIG_CMD_REGINFO * Register dump
865 CONFIG_CMD_RUN run command in env variable
866 CONFIG_CMD_SAVES * save S record dump
867 CONFIG_CMD_SCSI * SCSI Support
868 CONFIG_CMD_SDRAM * print SDRAM configuration information
869 (requires CONFIG_CMD_I2C)
870 CONFIG_CMD_SETGETDCR Support for DCR Register access
872 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
873 CONFIG_CMD_SHA1SUM print sha1 memory digest
874 (requires CONFIG_CMD_MEMORY)
875 CONFIG_CMD_SOURCE "source" command Support
876 CONFIG_CMD_SPI * SPI serial bus support
877 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
878 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
879 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
880 CONFIG_CMD_TIMER * access to the system tick timer
881 CONFIG_CMD_USB * USB support
882 CONFIG_CMD_CDP * Cisco Discover Protocol support
883 CONFIG_CMD_MFSL * Microblaze FSL support
886 EXAMPLE: If you want all functions except of network
887 support you can write:
889 #include "config_cmd_all.h"
890 #undef CONFIG_CMD_NET
893 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
895 Note: Don't enable the "icache" and "dcache" commands
896 (configuration option CONFIG_CMD_CACHE) unless you know
897 what you (and your U-Boot users) are doing. Data
898 cache cannot be enabled on systems like the 8xx or
899 8260 (where accesses to the IMMR region must be
900 uncached), and it cannot be disabled on all other
901 systems where we (mis-) use the data cache to hold an
902 initial stack and some data.
905 XXX - this list needs to get updated!
909 If this variable is defined, U-Boot will use a device tree
910 to configure its devices, instead of relying on statically
911 compiled #defines in the board file. This option is
912 experimental and only available on a few boards. The device
913 tree is available in the global data as gd->fdt_blob.
915 U-Boot needs to get its device tree from somewhere. This can
916 be done using one of the two options below:
919 If this variable is defined, U-Boot will embed a device tree
920 binary in its image. This device tree file should be in the
921 board directory and called <soc>-<board>.dts. The binary file
922 is then picked up in board_init_f() and made available through
923 the global data structure as gd->blob.
926 If this variable is defined, U-Boot will build a device tree
927 binary. It will be called u-boot.dtb. Architecture-specific
928 code will locate it at run-time. Generally this works by:
930 cat u-boot.bin u-boot.dtb >image.bin
932 and in fact, U-Boot does this for you, creating a file called
933 u-boot-dtb.bin which is useful in the common case. You can
934 still use the individual files if you need something more
939 If this variable is defined, it enables watchdog
940 support for the SoC. There must be support in the SoC
941 specific code for a watchdog. For the 8xx and 8260
942 CPUs, the SIU Watchdog feature is enabled in the SYPCR
943 register. When supported for a specific SoC is
944 available, then no further board specific code should
948 When using a watchdog circuitry external to the used
949 SoC, then define this variable and provide board
950 specific code for the "hw_watchdog_reset" function.
953 CONFIG_VERSION_VARIABLE
954 If this variable is defined, an environment variable
955 named "ver" is created by U-Boot showing the U-Boot
956 version as printed by the "version" command.
957 Any change to this variable will be reverted at the
962 When CONFIG_CMD_DATE is selected, the type of the RTC
963 has to be selected, too. Define exactly one of the
966 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
967 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
968 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
969 CONFIG_RTC_MC146818 - use MC146818 RTC
970 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
971 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
972 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
973 CONFIG_RTC_DS164x - use Dallas DS164x RTC
974 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
975 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
976 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
977 CONFIG_SYS_RV3029_TCR - enable trickle charger on
980 Note that if the RTC uses I2C, then the I2C interface
981 must also be configured. See I2C Support, below.
984 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
985 CONFIG_PCA953X_INFO - enable pca953x info command
987 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
988 chip-ngpio pairs that tell the PCA953X driver the number of
989 pins supported by a particular chip.
991 Note that if the GPIO device uses I2C, then the I2C interface
992 must also be configured. See I2C Support, below.
996 When CONFIG_TIMESTAMP is selected, the timestamp
997 (date and time) of an image is printed by image
998 commands like bootm or iminfo. This option is
999 automatically enabled when you select CONFIG_CMD_DATE .
1001 - Partition Labels (disklabels) Supported:
1002 Zero or more of the following:
1003 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1004 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1005 Intel architecture, USB sticks, etc.
1006 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1007 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1008 bootloader. Note 2TB partition limit; see
1010 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1012 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1013 CONFIG_CMD_SCSI) you must configure support for at
1014 least one non-MTD partition type as well.
1017 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1018 board configurations files but used nowhere!
1020 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1021 be performed by calling the function
1022 ide_set_reset(int reset)
1023 which has to be defined in a board specific file
1028 Set this to enable ATAPI support.
1033 Set this to enable support for disks larger than 137GB
1034 Also look at CONFIG_SYS_64BIT_LBA.
1035 Whithout these , LBA48 support uses 32bit variables and will 'only'
1036 support disks up to 2.1TB.
1038 CONFIG_SYS_64BIT_LBA:
1039 When enabled, makes the IDE subsystem use 64bit sector addresses.
1043 At the moment only there is only support for the
1044 SYM53C8XX SCSI controller; define
1045 CONFIG_SCSI_SYM53C8XX to enable it.
1047 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1048 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1049 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1050 maximum numbers of LUNs, SCSI ID's and target
1052 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1054 The environment variable 'scsidevs' is set to the number of
1055 SCSI devices found during the last scan.
1057 - NETWORK Support (PCI):
1059 Support for Intel 8254x/8257x gigabit chips.
1062 Utility code for direct access to the SPI bus on Intel 8257x.
1063 This does not do anything useful unless you set at least one
1064 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1066 CONFIG_E1000_SPI_GENERIC
1067 Allow generic access to the SPI bus on the Intel 8257x, for
1068 example with the "sspi" command.
1071 Management command for E1000 devices. When used on devices
1072 with SPI support you can reprogram the EEPROM from U-Boot.
1074 CONFIG_E1000_FALLBACK_MAC
1075 default MAC for empty EEPROM after production.
1078 Support for Intel 82557/82559/82559ER chips.
1079 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1080 write routine for first time initialisation.
1083 Support for Digital 2114x chips.
1084 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1085 modem chip initialisation (KS8761/QS6611).
1088 Support for National dp83815 chips.
1091 Support for National dp8382[01] gigabit chips.
1093 - NETWORK Support (other):
1095 CONFIG_DRIVER_AT91EMAC
1096 Support for AT91RM9200 EMAC.
1099 Define this to use reduced MII inteface
1101 CONFIG_DRIVER_AT91EMAC_QUIET
1102 If this defined, the driver is quiet.
1103 The driver doen't show link status messages.
1105 CONFIG_CALXEDA_XGMAC
1106 Support for the Calxeda XGMAC device
1109 Support for SMSC's LAN91C96 chips.
1111 CONFIG_LAN91C96_BASE
1112 Define this to hold the physical address
1113 of the LAN91C96's I/O space
1115 CONFIG_LAN91C96_USE_32_BIT
1116 Define this to enable 32 bit addressing
1119 Support for SMSC's LAN91C111 chip
1121 CONFIG_SMC91111_BASE
1122 Define this to hold the physical address
1123 of the device (I/O space)
1125 CONFIG_SMC_USE_32_BIT
1126 Define this if data bus is 32 bits
1128 CONFIG_SMC_USE_IOFUNCS
1129 Define this to use i/o functions instead of macros
1130 (some hardware wont work with macros)
1132 CONFIG_DRIVER_TI_EMAC
1133 Support for davinci emac
1135 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1136 Define this if you have more then 3 PHYs.
1139 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1141 CONFIG_FTGMAC100_EGIGA
1142 Define this to use GE link update with gigabit PHY.
1143 Define this if FTGMAC100 is connected to gigabit PHY.
1144 If your system has 10/100 PHY only, it might not occur
1145 wrong behavior. Because PHY usually return timeout or
1146 useless data when polling gigabit status and gigabit
1147 control registers. This behavior won't affect the
1148 correctnessof 10/100 link speed update.
1151 Support for SMSC's LAN911x and LAN921x chips
1154 Define this to hold the physical address
1155 of the device (I/O space)
1157 CONFIG_SMC911X_32_BIT
1158 Define this if data bus is 32 bits
1160 CONFIG_SMC911X_16_BIT
1161 Define this if data bus is 16 bits. If your processor
1162 automatically converts one 32 bit word to two 16 bit
1163 words you may also try CONFIG_SMC911X_32_BIT.
1166 Support for Renesas on-chip Ethernet controller
1168 CONFIG_SH_ETHER_USE_PORT
1169 Define the number of ports to be used
1171 CONFIG_SH_ETHER_PHY_ADDR
1172 Define the ETH PHY's address
1174 CONFIG_SH_ETHER_CACHE_WRITEBACK
1175 If this option is set, the driver enables cache flush.
1178 CONFIG_GENERIC_LPC_TPM
1179 Support for generic parallel port TPM devices. Only one device
1180 per system is supported at this time.
1182 CONFIG_TPM_TIS_BASE_ADDRESS
1183 Base address where the generic TPM device is mapped
1184 to. Contemporary x86 systems usually map it at
1188 At the moment only the UHCI host controller is
1189 supported (PIP405, MIP405, MPC5200); define
1190 CONFIG_USB_UHCI to enable it.
1191 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1192 and define CONFIG_USB_STORAGE to enable the USB
1195 Supported are USB Keyboards and USB Floppy drives
1197 MPC5200 USB requires additional defines:
1199 for 528 MHz Clock: 0x0001bbbb
1203 for differential drivers: 0x00001000
1204 for single ended drivers: 0x00005000
1205 for differential drivers on PSC3: 0x00000100
1206 for single ended drivers on PSC3: 0x00004100
1207 CONFIG_SYS_USB_EVENT_POLL
1208 May be defined to allow interrupt polling
1209 instead of using asynchronous interrupts
1211 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1212 txfilltuning field in the EHCI controller on reset.
1215 Define the below if you wish to use the USB console.
1216 Once firmware is rebuilt from a serial console issue the
1217 command "setenv stdin usbtty; setenv stdout usbtty" and
1218 attach your USB cable. The Unix command "dmesg" should print
1219 it has found a new device. The environment variable usbtty
1220 can be set to gserial or cdc_acm to enable your device to
1221 appear to a USB host as a Linux gserial device or a
1222 Common Device Class Abstract Control Model serial device.
1223 If you select usbtty = gserial you should be able to enumerate
1225 # modprobe usbserial vendor=0xVendorID product=0xProductID
1226 else if using cdc_acm, simply setting the environment
1227 variable usbtty to be cdc_acm should suffice. The following
1228 might be defined in YourBoardName.h
1231 Define this to build a UDC device
1234 Define this to have a tty type of device available to
1235 talk to the UDC device
1238 Define this to enable the high speed support for usb
1239 device and usbtty. If this feature is enabled, a routine
1240 int is_usbd_high_speed(void)
1241 also needs to be defined by the driver to dynamically poll
1242 whether the enumeration has succeded at high speed or full
1245 CONFIG_SYS_CONSOLE_IS_IN_ENV
1246 Define this if you want stdin, stdout &/or stderr to
1250 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1251 Derive USB clock from external clock "blah"
1252 - CONFIG_SYS_USB_EXTC_CLK 0x02
1254 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1255 Derive USB clock from brgclk
1256 - CONFIG_SYS_USB_BRG_CLK 0x04
1258 If you have a USB-IF assigned VendorID then you may wish to
1259 define your own vendor specific values either in BoardName.h
1260 or directly in usbd_vendor_info.h. If you don't define
1261 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1262 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1263 should pretend to be a Linux device to it's target host.
1265 CONFIG_USBD_MANUFACTURER
1266 Define this string as the name of your company for
1267 - CONFIG_USBD_MANUFACTURER "my company"
1269 CONFIG_USBD_PRODUCT_NAME
1270 Define this string as the name of your product
1271 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1273 CONFIG_USBD_VENDORID
1274 Define this as your assigned Vendor ID from the USB
1275 Implementors Forum. This *must* be a genuine Vendor ID
1276 to avoid polluting the USB namespace.
1277 - CONFIG_USBD_VENDORID 0xFFFF
1279 CONFIG_USBD_PRODUCTID
1280 Define this as the unique Product ID
1282 - CONFIG_USBD_PRODUCTID 0xFFFF
1284 - ULPI Layer Support:
1285 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1286 the generic ULPI layer. The generic layer accesses the ULPI PHY
1287 via the platform viewport, so you need both the genric layer and
1288 the viewport enabled. Currently only Chipidea/ARC based
1289 viewport is supported.
1290 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1291 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1292 If your ULPI phy needs a different reference clock than the
1293 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1294 the appropriate value in Hz.
1297 The MMC controller on the Intel PXA is supported. To
1298 enable this define CONFIG_MMC. The MMC can be
1299 accessed from the boot prompt by mapping the device
1300 to physical memory similar to flash. Command line is
1301 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1302 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1305 Support for Renesas on-chip MMCIF controller
1307 CONFIG_SH_MMCIF_ADDR
1308 Define the base address of MMCIF registers
1311 Define the clock frequency for MMCIF
1313 - Journaling Flash filesystem support:
1314 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1315 CONFIG_JFFS2_NAND_DEV
1316 Define these for a default partition on a NAND device
1318 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1319 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1320 Define these for a default partition on a NOR device
1322 CONFIG_SYS_JFFS_CUSTOM_PART
1323 Define this to create an own partition. You have to provide a
1324 function struct part_info* jffs2_part_info(int part_num)
1326 If you define only one JFFS2 partition you may also want to
1327 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1328 to disable the command chpart. This is the default when you
1329 have not defined a custom partition
1331 - FAT(File Allocation Table) filesystem write function support:
1334 Define this to enable support for saving memory data as a
1335 file in FAT formatted partition.
1337 This will also enable the command "fatwrite" enabling the
1338 user to write files to FAT.
1340 CBFS (Coreboot Filesystem) support
1343 Define this to enable support for reading from a Coreboot
1344 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1350 Define this to enable standard (PC-Style) keyboard
1354 Standard PC keyboard driver with US (is default) and
1355 GERMAN key layout (switch via environment 'keymap=de') support.
1356 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1357 for cfb_console. Supports cursor blinking.
1362 Define this to enable video support (for output to
1365 CONFIG_VIDEO_CT69000
1367 Enable Chips & Technologies 69000 Video chip
1369 CONFIG_VIDEO_SMI_LYNXEM
1370 Enable Silicon Motion SMI 712/710/810 Video chip. The
1371 video output is selected via environment 'videoout'
1372 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1375 For the CT69000 and SMI_LYNXEM drivers, videomode is
1376 selected via environment 'videomode'. Two different ways
1378 - "videomode=num" 'num' is a standard LiLo mode numbers.
1379 Following standard modes are supported (* is default):
1381 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1382 -------------+---------------------------------------------
1383 8 bits | 0x301* 0x303 0x305 0x161 0x307
1384 15 bits | 0x310 0x313 0x316 0x162 0x319
1385 16 bits | 0x311 0x314 0x317 0x163 0x31A
1386 24 bits | 0x312 0x315 0x318 ? 0x31B
1387 -------------+---------------------------------------------
1388 (i.e. setenv videomode 317; saveenv; reset;)
1390 - "videomode=bootargs" all the video parameters are parsed
1391 from the bootargs. (See drivers/video/videomodes.c)
1394 CONFIG_VIDEO_SED13806
1395 Enable Epson SED13806 driver. This driver supports 8bpp
1396 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1397 or CONFIG_VIDEO_SED13806_16BPP
1400 Enable the Freescale DIU video driver. Reference boards for
1401 SOCs that have a DIU should define this macro to enable DIU
1402 support, and should also define these other macros:
1408 CONFIG_VIDEO_SW_CURSOR
1409 CONFIG_VGA_AS_SINGLE_DEVICE
1411 CONFIG_VIDEO_BMP_LOGO
1413 The DIU driver will look for the 'video-mode' environment
1414 variable, and if defined, enable the DIU as a console during
1415 boot. See the documentation file README.video for a
1416 description of this variable.
1420 Enable the VGA video / BIOS for x86. The alternative if you
1421 are using coreboot is to use the coreboot frame buffer
1428 Define this to enable a custom keyboard support.
1429 This simply calls drv_keyboard_init() which must be
1430 defined in your board-specific files.
1431 The only board using this so far is RBC823.
1433 - LCD Support: CONFIG_LCD
1435 Define this to enable LCD support (for output to LCD
1436 display); also select one of the supported displays
1437 by defining one of these:
1441 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1443 CONFIG_NEC_NL6448AC33:
1445 NEC NL6448AC33-18. Active, color, single scan.
1447 CONFIG_NEC_NL6448BC20
1449 NEC NL6448BC20-08. 6.5", 640x480.
1450 Active, color, single scan.
1452 CONFIG_NEC_NL6448BC33_54
1454 NEC NL6448BC33-54. 10.4", 640x480.
1455 Active, color, single scan.
1459 Sharp 320x240. Active, color, single scan.
1460 It isn't 16x9, and I am not sure what it is.
1462 CONFIG_SHARP_LQ64D341
1464 Sharp LQ64D341 display, 640x480.
1465 Active, color, single scan.
1469 HLD1045 display, 640x480.
1470 Active, color, single scan.
1474 Optrex CBL50840-2 NF-FW 99 22 M5
1476 Hitachi LMG6912RPFC-00T
1480 320x240. Black & white.
1482 Normally display is black on white background; define
1483 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1487 Support drawing of RLE8-compressed bitmaps on the LCD.
1490 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1492 If this option is set, the environment is checked for
1493 a variable "splashimage". If found, the usual display
1494 of logo, copyright and system information on the LCD
1495 is suppressed and the BMP image at the address
1496 specified in "splashimage" is loaded instead. The
1497 console is redirected to the "nulldev", too. This
1498 allows for a "silent" boot where a splash screen is
1499 loaded very quickly after power-on.
1501 CONFIG_SPLASH_SCREEN_ALIGN
1503 If this option is set the splash image can be freely positioned
1504 on the screen. Environment variable "splashpos" specifies the
1505 position as "x,y". If a positive number is given it is used as
1506 number of pixel from left/top. If a negative number is given it
1507 is used as number of pixel from right/bottom. You can also
1508 specify 'm' for centering the image.
1511 setenv splashpos m,m
1512 => image at center of screen
1514 setenv splashpos 30,20
1515 => image at x = 30 and y = 20
1517 setenv splashpos -10,m
1518 => vertically centered image
1519 at x = dspWidth - bmpWidth - 9
1521 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1523 If this option is set, additionally to standard BMP
1524 images, gzipped BMP images can be displayed via the
1525 splashscreen support or the bmp command.
1527 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1529 If this option is set, 8-bit RLE compressed BMP images
1530 can be displayed via the splashscreen support or the
1533 - Do compresssing for memory range:
1536 If this option is set, it would use zlib deflate method
1537 to compress the specified memory at its best effort.
1539 - Compression support:
1542 If this option is set, support for bzip2 compressed
1543 images is included. If not, only uncompressed and gzip
1544 compressed images are supported.
1546 NOTE: the bzip2 algorithm requires a lot of RAM, so
1547 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1552 If this option is set, support for lzma compressed
1555 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1556 requires an amount of dynamic memory that is given by the
1559 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1561 Where lc and lp stand for, respectively, Literal context bits
1562 and Literal pos bits.
1564 This value is upper-bounded by 14MB in the worst case. Anyway,
1565 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1566 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1567 a very small buffer.
1569 Use the lzmainfo tool to determinate the lc and lp values and
1570 then calculate the amount of needed dynamic memory (ensuring
1571 the appropriate CONFIG_SYS_MALLOC_LEN value).
1576 The address of PHY on MII bus.
1578 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1580 The clock frequency of the MII bus
1584 If this option is set, support for speed/duplex
1585 detection of gigabit PHY is included.
1587 CONFIG_PHY_RESET_DELAY
1589 Some PHY like Intel LXT971A need extra delay after
1590 reset before any MII register access is possible.
1591 For such PHY, set this option to the usec delay
1592 required. (minimum 300usec for LXT971A)
1594 CONFIG_PHY_CMD_DELAY (ppc4xx)
1596 Some PHY like Intel LXT971A need extra delay after
1597 command issued before MII status register can be read
1607 Define a default value for Ethernet address to use
1608 for the respective Ethernet interface, in case this
1609 is not determined automatically.
1614 Define a default value for the IP address to use for
1615 the default Ethernet interface, in case this is not
1616 determined through e.g. bootp.
1617 (Environment variable "ipaddr")
1619 - Server IP address:
1622 Defines a default value for the IP address of a TFTP
1623 server to contact when using the "tftboot" command.
1624 (Environment variable "serverip")
1626 CONFIG_KEEP_SERVERADDR
1628 Keeps the server's MAC address, in the env 'serveraddr'
1629 for passing to bootargs (like Linux's netconsole option)
1631 - Gateway IP address:
1634 Defines a default value for the IP address of the
1635 default router where packets to other networks are
1637 (Environment variable "gatewayip")
1642 Defines a default value for the subnet mask (or
1643 routing prefix) which is used to determine if an IP
1644 address belongs to the local subnet or needs to be
1645 forwarded through a router.
1646 (Environment variable "netmask")
1648 - Multicast TFTP Mode:
1651 Defines whether you want to support multicast TFTP as per
1652 rfc-2090; for example to work with atftp. Lets lots of targets
1653 tftp down the same boot image concurrently. Note: the Ethernet
1654 driver in use must provide a function: mcast() to join/leave a
1657 - BOOTP Recovery Mode:
1658 CONFIG_BOOTP_RANDOM_DELAY
1660 If you have many targets in a network that try to
1661 boot using BOOTP, you may want to avoid that all
1662 systems send out BOOTP requests at precisely the same
1663 moment (which would happen for instance at recovery
1664 from a power failure, when all systems will try to
1665 boot, thus flooding the BOOTP server. Defining
1666 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1667 inserted before sending out BOOTP requests. The
1668 following delays are inserted then:
1670 1st BOOTP request: delay 0 ... 1 sec
1671 2nd BOOTP request: delay 0 ... 2 sec
1672 3rd BOOTP request: delay 0 ... 4 sec
1674 BOOTP requests: delay 0 ... 8 sec
1676 - DHCP Advanced Options:
1677 You can fine tune the DHCP functionality by defining
1678 CONFIG_BOOTP_* symbols:
1680 CONFIG_BOOTP_SUBNETMASK
1681 CONFIG_BOOTP_GATEWAY
1682 CONFIG_BOOTP_HOSTNAME
1683 CONFIG_BOOTP_NISDOMAIN
1684 CONFIG_BOOTP_BOOTPATH
1685 CONFIG_BOOTP_BOOTFILESIZE
1688 CONFIG_BOOTP_SEND_HOSTNAME
1689 CONFIG_BOOTP_NTPSERVER
1690 CONFIG_BOOTP_TIMEOFFSET
1691 CONFIG_BOOTP_VENDOREX
1692 CONFIG_BOOTP_MAY_FAIL
1694 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1695 environment variable, not the BOOTP server.
1697 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1698 after the configured retry count, the call will fail
1699 instead of starting over. This can be used to fail over
1700 to Link-local IP address configuration if the DHCP server
1703 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1704 serverip from a DHCP server, it is possible that more
1705 than one DNS serverip is offered to the client.
1706 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1707 serverip will be stored in the additional environment
1708 variable "dnsip2". The first DNS serverip is always
1709 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1712 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1713 to do a dynamic update of a DNS server. To do this, they
1714 need the hostname of the DHCP requester.
1715 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1716 of the "hostname" environment variable is passed as
1717 option 12 to the DHCP server.
1719 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1721 A 32bit value in microseconds for a delay between
1722 receiving a "DHCP Offer" and sending the "DHCP Request".
1723 This fixes a problem with certain DHCP servers that don't
1724 respond 100% of the time to a "DHCP request". E.g. On an
1725 AT91RM9200 processor running at 180MHz, this delay needed
1726 to be *at least* 15,000 usec before a Windows Server 2003
1727 DHCP server would reply 100% of the time. I recommend at
1728 least 50,000 usec to be safe. The alternative is to hope
1729 that one of the retries will be successful but note that
1730 the DHCP timeout and retry process takes a longer than
1733 - Link-local IP address negotiation:
1734 Negotiate with other link-local clients on the local network
1735 for an address that doesn't require explicit configuration.
1736 This is especially useful if a DHCP server cannot be guaranteed
1737 to exist in all environments that the device must operate.
1739 See doc/README.link-local for more information.
1742 CONFIG_CDP_DEVICE_ID
1744 The device id used in CDP trigger frames.
1746 CONFIG_CDP_DEVICE_ID_PREFIX
1748 A two character string which is prefixed to the MAC address
1753 A printf format string which contains the ascii name of
1754 the port. Normally is set to "eth%d" which sets
1755 eth0 for the first Ethernet, eth1 for the second etc.
1757 CONFIG_CDP_CAPABILITIES
1759 A 32bit integer which indicates the device capabilities;
1760 0x00000010 for a normal host which does not forwards.
1764 An ascii string containing the version of the software.
1768 An ascii string containing the name of the platform.
1772 A 32bit integer sent on the trigger.
1774 CONFIG_CDP_POWER_CONSUMPTION
1776 A 16bit integer containing the power consumption of the
1777 device in .1 of milliwatts.
1779 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1781 A byte containing the id of the VLAN.
1783 - Status LED: CONFIG_STATUS_LED
1785 Several configurations allow to display the current
1786 status using a LED. For instance, the LED will blink
1787 fast while running U-Boot code, stop blinking as
1788 soon as a reply to a BOOTP request was received, and
1789 start blinking slow once the Linux kernel is running
1790 (supported by a status LED driver in the Linux
1791 kernel). Defining CONFIG_STATUS_LED enables this
1794 - CAN Support: CONFIG_CAN_DRIVER
1796 Defining CONFIG_CAN_DRIVER enables CAN driver support
1797 on those systems that support this (optional)
1798 feature, like the TQM8xxL modules.
1800 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1802 These enable I2C serial bus commands. Defining either of
1803 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1804 include the appropriate I2C driver for the selected CPU.
1806 This will allow you to use i2c commands at the u-boot
1807 command line (as long as you set CONFIG_CMD_I2C in
1808 CONFIG_COMMANDS) and communicate with i2c based realtime
1809 clock chips. See common/cmd_i2c.c for a description of the
1810 command line interface.
1812 CONFIG_HARD_I2C selects a hardware I2C controller.
1814 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1815 bit-banging) driver instead of CPM or similar hardware
1818 There are several other quantities that must also be
1819 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1821 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1822 to be the frequency (in Hz) at which you wish your i2c bus
1823 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1824 the CPU's i2c node address).
1826 Now, the u-boot i2c code for the mpc8xx
1827 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1828 and so its address should therefore be cleared to 0 (See,
1829 eg, MPC823e User's Manual p.16-473). So, set
1830 CONFIG_SYS_I2C_SLAVE to 0.
1832 CONFIG_SYS_I2C_INIT_MPC5XXX
1834 When a board is reset during an i2c bus transfer
1835 chips might think that the current transfer is still
1836 in progress. Reset the slave devices by sending start
1837 commands until the slave device responds.
1839 That's all that's required for CONFIG_HARD_I2C.
1841 If you use the software i2c interface (CONFIG_SOFT_I2C)
1842 then the following macros need to be defined (examples are
1843 from include/configs/lwmon.h):
1847 (Optional). Any commands necessary to enable the I2C
1848 controller or configure ports.
1850 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1854 (Only for MPC8260 CPU). The I/O port to use (the code
1855 assumes both bits are on the same port). Valid values
1856 are 0..3 for ports A..D.
1860 The code necessary to make the I2C data line active
1861 (driven). If the data line is open collector, this
1864 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1868 The code necessary to make the I2C data line tri-stated
1869 (inactive). If the data line is open collector, this
1872 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1876 Code that returns TRUE if the I2C data line is high,
1879 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1883 If <bit> is TRUE, sets the I2C data line high. If it
1884 is FALSE, it clears it (low).
1886 eg: #define I2C_SDA(bit) \
1887 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1888 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1892 If <bit> is TRUE, sets the I2C clock line high. If it
1893 is FALSE, it clears it (low).
1895 eg: #define I2C_SCL(bit) \
1896 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1897 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1901 This delay is invoked four times per clock cycle so this
1902 controls the rate of data transfer. The data rate thus
1903 is 1 / (I2C_DELAY * 4). Often defined to be something
1906 #define I2C_DELAY udelay(2)
1908 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1910 If your arch supports the generic GPIO framework (asm/gpio.h),
1911 then you may alternatively define the two GPIOs that are to be
1912 used as SCL / SDA. Any of the previous I2C_xxx macros will
1913 have GPIO-based defaults assigned to them as appropriate.
1915 You should define these to the GPIO value as given directly to
1916 the generic GPIO functions.
1918 CONFIG_SYS_I2C_INIT_BOARD
1920 When a board is reset during an i2c bus transfer
1921 chips might think that the current transfer is still
1922 in progress. On some boards it is possible to access
1923 the i2c SCLK line directly, either by using the
1924 processor pin as a GPIO or by having a second pin
1925 connected to the bus. If this option is defined a
1926 custom i2c_init_board() routine in boards/xxx/board.c
1927 is run early in the boot sequence.
1929 CONFIG_SYS_I2C_BOARD_LATE_INIT
1931 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1932 defined a custom i2c_board_late_init() routine in
1933 boards/xxx/board.c is run AFTER the operations in i2c_init()
1934 is completed. This callpoint can be used to unreset i2c bus
1935 using CPU i2c controller register accesses for CPUs whose i2c
1936 controller provide such a method. It is called at the end of
1937 i2c_init() to allow i2c_init operations to setup the i2c bus
1938 controller on the CPU (e.g. setting bus speed & slave address).
1940 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1942 This option enables configuration of bi_iic_fast[] flags
1943 in u-boot bd_info structure based on u-boot environment
1944 variable "i2cfast". (see also i2cfast)
1946 CONFIG_I2C_MULTI_BUS
1948 This option allows the use of multiple I2C buses, each of which
1949 must have a controller. At any point in time, only one bus is
1950 active. To switch to a different bus, use the 'i2c dev' command.
1951 Note that bus numbering is zero-based.
1953 CONFIG_SYS_I2C_NOPROBES
1955 This option specifies a list of I2C devices that will be skipped
1956 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1957 is set, specify a list of bus-device pairs. Otherwise, specify
1958 a 1D array of device addresses
1961 #undef CONFIG_I2C_MULTI_BUS
1962 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1964 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1966 #define CONFIG_I2C_MULTI_BUS
1967 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1969 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1971 CONFIG_SYS_SPD_BUS_NUM
1973 If defined, then this indicates the I2C bus number for DDR SPD.
1974 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1976 CONFIG_SYS_RTC_BUS_NUM
1978 If defined, then this indicates the I2C bus number for the RTC.
1979 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1981 CONFIG_SYS_DTT_BUS_NUM
1983 If defined, then this indicates the I2C bus number for the DTT.
1984 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1986 CONFIG_SYS_I2C_DTT_ADDR:
1988 If defined, specifies the I2C address of the DTT device.
1989 If not defined, then U-Boot uses predefined value for
1990 specified DTT device.
1994 Define this option if you want to use Freescale's I2C driver in
1995 drivers/i2c/fsl_i2c.c.
1999 Define this option if you have I2C devices reached over 1 .. n
2000 I2C Muxes like the pca9544a. This option addes a new I2C
2001 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
2002 new I2C Bus to the existing I2C Busses. If you select the
2003 new Bus with "i2c dev", u-bbot sends first the commandos for
2004 the muxes to activate this new "bus".
2006 CONFIG_I2C_MULTI_BUS must be also defined, to use this
2010 Adding a new I2C Bus reached over 2 pca9544a muxes
2011 The First mux with address 70 and channel 6
2012 The Second mux with address 71 and channel 4
2014 => i2c bus pca9544a:70:6:pca9544a:71:4
2016 Use the "i2c bus" command without parameter, to get a list
2017 of I2C Busses with muxes:
2020 Busses reached over muxes:
2022 reached over Mux(es):
2025 reached over Mux(es):
2030 If you now switch to the new I2C Bus 3 with "i2c dev 3"
2031 u-boot first sends the command to the mux@70 to enable
2032 channel 6, and then the command to the mux@71 to enable
2035 After that, you can use the "normal" i2c commands as
2036 usual to communicate with your I2C devices behind
2039 This option is actually implemented for the bitbanging
2040 algorithm in common/soft_i2c.c and for the Hardware I2C
2041 Bus on the MPC8260. But it should be not so difficult
2042 to add this option to other architectures.
2044 CONFIG_SOFT_I2C_READ_REPEATED_START
2046 defining this will force the i2c_read() function in
2047 the soft_i2c driver to perform an I2C repeated start
2048 between writing the address pointer and reading the
2049 data. If this define is omitted the default behaviour
2050 of doing a stop-start sequence will be used. Most I2C
2051 devices can use either method, but some require one or
2054 - SPI Support: CONFIG_SPI
2056 Enables SPI driver (so far only tested with
2057 SPI EEPROM, also an instance works with Crystal A/D and
2058 D/As on the SACSng board)
2062 Enables the driver for SPI controller on SuperH. Currently
2063 only SH7757 is supported.
2067 Enables extended (16-bit) SPI EEPROM addressing.
2068 (symmetrical to CONFIG_I2C_X)
2072 Enables a software (bit-bang) SPI driver rather than
2073 using hardware support. This is a general purpose
2074 driver that only requires three general I/O port pins
2075 (two outputs, one input) to function. If this is
2076 defined, the board configuration must define several
2077 SPI configuration items (port pins to use, etc). For
2078 an example, see include/configs/sacsng.h.
2082 Enables a hardware SPI driver for general-purpose reads
2083 and writes. As with CONFIG_SOFT_SPI, the board configuration
2084 must define a list of chip-select function pointers.
2085 Currently supported on some MPC8xxx processors. For an
2086 example, see include/configs/mpc8349emds.h.
2090 Enables the driver for the SPI controllers on i.MX and MXC
2091 SoCs. Currently i.MX31/35/51 are supported.
2093 - FPGA Support: CONFIG_FPGA
2095 Enables FPGA subsystem.
2097 CONFIG_FPGA_<vendor>
2099 Enables support for specific chip vendors.
2102 CONFIG_FPGA_<family>
2104 Enables support for FPGA family.
2105 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2109 Specify the number of FPGA devices to support.
2111 CONFIG_SYS_FPGA_PROG_FEEDBACK
2113 Enable printing of hash marks during FPGA configuration.
2115 CONFIG_SYS_FPGA_CHECK_BUSY
2117 Enable checks on FPGA configuration interface busy
2118 status by the configuration function. This option
2119 will require a board or device specific function to
2124 If defined, a function that provides delays in the FPGA
2125 configuration driver.
2127 CONFIG_SYS_FPGA_CHECK_CTRLC
2128 Allow Control-C to interrupt FPGA configuration
2130 CONFIG_SYS_FPGA_CHECK_ERROR
2132 Check for configuration errors during FPGA bitfile
2133 loading. For example, abort during Virtex II
2134 configuration if the INIT_B line goes low (which
2135 indicated a CRC error).
2137 CONFIG_SYS_FPGA_WAIT_INIT
2139 Maximum time to wait for the INIT_B line to deassert
2140 after PROB_B has been deasserted during a Virtex II
2141 FPGA configuration sequence. The default time is 500
2144 CONFIG_SYS_FPGA_WAIT_BUSY
2146 Maximum time to wait for BUSY to deassert during
2147 Virtex II FPGA configuration. The default is 5 ms.
2149 CONFIG_SYS_FPGA_WAIT_CONFIG
2151 Time to wait after FPGA configuration. The default is
2154 - Configuration Management:
2157 If defined, this string will be added to the U-Boot
2158 version information (U_BOOT_VERSION)
2160 - Vendor Parameter Protection:
2162 U-Boot considers the values of the environment
2163 variables "serial#" (Board Serial Number) and
2164 "ethaddr" (Ethernet Address) to be parameters that
2165 are set once by the board vendor / manufacturer, and
2166 protects these variables from casual modification by
2167 the user. Once set, these variables are read-only,
2168 and write or delete attempts are rejected. You can
2169 change this behaviour:
2171 If CONFIG_ENV_OVERWRITE is #defined in your config
2172 file, the write protection for vendor parameters is
2173 completely disabled. Anybody can change or delete
2176 Alternatively, if you #define _both_ CONFIG_ETHADDR
2177 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2178 Ethernet address is installed in the environment,
2179 which can be changed exactly ONCE by the user. [The
2180 serial# is unaffected by this, i. e. it remains
2186 Define this variable to enable the reservation of
2187 "protected RAM", i. e. RAM which is not overwritten
2188 by U-Boot. Define CONFIG_PRAM to hold the number of
2189 kB you want to reserve for pRAM. You can overwrite
2190 this default value by defining an environment
2191 variable "pram" to the number of kB you want to
2192 reserve. Note that the board info structure will
2193 still show the full amount of RAM. If pRAM is
2194 reserved, a new environment variable "mem" will
2195 automatically be defined to hold the amount of
2196 remaining RAM in a form that can be passed as boot
2197 argument to Linux, for instance like that:
2199 setenv bootargs ... mem=\${mem}
2202 This way you can tell Linux not to use this memory,
2203 either, which results in a memory region that will
2204 not be affected by reboots.
2206 *WARNING* If your board configuration uses automatic
2207 detection of the RAM size, you must make sure that
2208 this memory test is non-destructive. So far, the
2209 following board configurations are known to be
2212 IVMS8, IVML24, SPD8xx, TQM8xxL,
2213 HERMES, IP860, RPXlite, LWMON,
2216 - Access to physical memory region (> 4GB)
2217 Some basic support is provided for operations on memory not
2218 normally accessible to U-Boot - e.g. some architectures
2219 support access to more than 4GB of memory on 32-bit
2220 machines using physical address extension or similar.
2221 Define CONFIG_PHYSMEM to access this basic support, which
2222 currently only supports clearing the memory.
2227 Define this variable to stop the system in case of a
2228 fatal error, so that you have to reset it manually.
2229 This is probably NOT a good idea for an embedded
2230 system where you want the system to reboot
2231 automatically as fast as possible, but it may be
2232 useful during development since you can try to debug
2233 the conditions that lead to the situation.
2235 CONFIG_NET_RETRY_COUNT
2237 This variable defines the number of retries for
2238 network operations like ARP, RARP, TFTP, or BOOTP
2239 before giving up the operation. If not defined, a
2240 default value of 5 is used.
2244 Timeout waiting for an ARP reply in milliseconds.
2248 Timeout in milliseconds used in NFS protocol.
2249 If you encounter "ERROR: Cannot umount" in nfs command,
2250 try longer timeout such as
2251 #define CONFIG_NFS_TIMEOUT 10000UL
2253 - Command Interpreter:
2254 CONFIG_AUTO_COMPLETE
2256 Enable auto completion of commands using TAB.
2258 Note that this feature has NOT been implemented yet
2259 for the "hush" shell.
2262 CONFIG_SYS_HUSH_PARSER
2264 Define this variable to enable the "hush" shell (from
2265 Busybox) as command line interpreter, thus enabling
2266 powerful command line syntax like
2267 if...then...else...fi conditionals or `&&' and '||'
2268 constructs ("shell scripts").
2270 If undefined, you get the old, much simpler behaviour
2271 with a somewhat smaller memory footprint.
2274 CONFIG_SYS_PROMPT_HUSH_PS2
2276 This defines the secondary prompt string, which is
2277 printed when the command interpreter needs more input
2278 to complete a command. Usually "> ".
2282 In the current implementation, the local variables
2283 space and global environment variables space are
2284 separated. Local variables are those you define by
2285 simply typing `name=value'. To access a local
2286 variable later on, you have write `$name' or
2287 `${name}'; to execute the contents of a variable
2288 directly type `$name' at the command prompt.
2290 Global environment variables are those you use
2291 setenv/printenv to work with. To run a command stored
2292 in such a variable, you need to use the run command,
2293 and you must not use the '$' sign to access them.
2295 To store commands and special characters in a
2296 variable, please use double quotation marks
2297 surrounding the whole text of the variable, instead
2298 of the backslashes before semicolons and special
2301 - Commandline Editing and History:
2302 CONFIG_CMDLINE_EDITING
2304 Enable editing and History functions for interactive
2305 commandline input operations
2307 - Default Environment:
2308 CONFIG_EXTRA_ENV_SETTINGS
2310 Define this to contain any number of null terminated
2311 strings (variable = value pairs) that will be part of
2312 the default environment compiled into the boot image.
2314 For example, place something like this in your
2315 board's config file:
2317 #define CONFIG_EXTRA_ENV_SETTINGS \
2321 Warning: This method is based on knowledge about the
2322 internal format how the environment is stored by the
2323 U-Boot code. This is NOT an official, exported
2324 interface! Although it is unlikely that this format
2325 will change soon, there is no guarantee either.
2326 You better know what you are doing here.
2328 Note: overly (ab)use of the default environment is
2329 discouraged. Make sure to check other ways to preset
2330 the environment like the "source" command or the
2333 CONFIG_ENV_VARS_UBOOT_CONFIG
2335 Define this in order to add variables describing the
2336 U-Boot build configuration to the default environment.
2337 These will be named arch, cpu, board, vendor, and soc.
2339 Enabling this option will cause the following to be defined:
2347 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2349 Define this in order to add variables describing certain
2350 run-time determined information about the hardware to the
2351 environment. These will be named board_name, board_rev.
2353 - DataFlash Support:
2354 CONFIG_HAS_DATAFLASH
2356 Defining this option enables DataFlash features and
2357 allows to read/write in Dataflash via the standard
2360 - Serial Flash support
2363 Defining this option enables SPI flash commands
2364 'sf probe/read/write/erase/update'.
2366 Usage requires an initial 'probe' to define the serial
2367 flash parameters, followed by read/write/erase/update
2370 The following defaults may be provided by the platform
2371 to handle the common case when only a single serial
2372 flash is present on the system.
2374 CONFIG_SF_DEFAULT_BUS Bus identifier
2375 CONFIG_SF_DEFAULT_CS Chip-select
2376 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2377 CONFIG_SF_DEFAULT_SPEED in Hz
2379 - SystemACE Support:
2382 Adding this option adds support for Xilinx SystemACE
2383 chips attached via some sort of local bus. The address
2384 of the chip must also be defined in the
2385 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2387 #define CONFIG_SYSTEMACE
2388 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2390 When SystemACE support is added, the "ace" device type
2391 becomes available to the fat commands, i.e. fatls.
2393 - TFTP Fixed UDP Port:
2396 If this is defined, the environment variable tftpsrcp
2397 is used to supply the TFTP UDP source port value.
2398 If tftpsrcp isn't defined, the normal pseudo-random port
2399 number generator is used.
2401 Also, the environment variable tftpdstp is used to supply
2402 the TFTP UDP destination port value. If tftpdstp isn't
2403 defined, the normal port 69 is used.
2405 The purpose for tftpsrcp is to allow a TFTP server to
2406 blindly start the TFTP transfer using the pre-configured
2407 target IP address and UDP port. This has the effect of
2408 "punching through" the (Windows XP) firewall, allowing
2409 the remainder of the TFTP transfer to proceed normally.
2410 A better solution is to properly configure the firewall,
2411 but sometimes that is not allowed.
2413 - Show boot progress:
2414 CONFIG_SHOW_BOOT_PROGRESS
2416 Defining this option allows to add some board-
2417 specific code (calling a user-provided function
2418 "show_boot_progress(int)") that enables you to show
2419 the system's boot progress on some display (for
2420 example, some LED's) on your board. At the moment,
2421 the following checkpoints are implemented:
2423 - Detailed boot stage timing
2425 Define this option to get detailed timing of each stage
2426 of the boot process.
2428 CONFIG_BOOTSTAGE_USER_COUNT
2429 This is the number of available user bootstage records.
2430 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2431 a new ID will be allocated from this stash. If you exceed
2432 the limit, recording will stop.
2434 CONFIG_BOOTSTAGE_REPORT
2435 Define this to print a report before boot, similar to this:
2437 Timer summary in microseconds:
2440 3,575,678 3,575,678 board_init_f start
2441 3,575,695 17 arch_cpu_init A9
2442 3,575,777 82 arch_cpu_init done
2443 3,659,598 83,821 board_init_r start
2444 3,910,375 250,777 main_loop
2445 29,916,167 26,005,792 bootm_start
2446 30,361,327 445,160 start_kernel
2448 CONFIG_CMD_BOOTSTAGE
2449 Add a 'bootstage' command which supports printing a report
2450 and un/stashing of bootstage data.
2452 CONFIG_BOOTSTAGE_FDT
2453 Stash the bootstage information in the FDT. A root 'bootstage'
2454 node is created with each bootstage id as a child. Each child
2455 has a 'name' property and either 'mark' containing the
2456 mark time in microsecond, or 'accum' containing the
2457 accumulated time for that bootstage id in microseconds.
2462 name = "board_init_f";
2471 Code in the Linux kernel can find this in /proc/devicetree.
2473 Legacy uImage format:
2476 1 common/cmd_bootm.c before attempting to boot an image
2477 -1 common/cmd_bootm.c Image header has bad magic number
2478 2 common/cmd_bootm.c Image header has correct magic number
2479 -2 common/cmd_bootm.c Image header has bad checksum
2480 3 common/cmd_bootm.c Image header has correct checksum
2481 -3 common/cmd_bootm.c Image data has bad checksum
2482 4 common/cmd_bootm.c Image data has correct checksum
2483 -4 common/cmd_bootm.c Image is for unsupported architecture
2484 5 common/cmd_bootm.c Architecture check OK
2485 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2486 6 common/cmd_bootm.c Image Type check OK
2487 -6 common/cmd_bootm.c gunzip uncompression error
2488 -7 common/cmd_bootm.c Unimplemented compression type
2489 7 common/cmd_bootm.c Uncompression OK
2490 8 common/cmd_bootm.c No uncompress/copy overwrite error
2491 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2493 9 common/image.c Start initial ramdisk verification
2494 -10 common/image.c Ramdisk header has bad magic number
2495 -11 common/image.c Ramdisk header has bad checksum
2496 10 common/image.c Ramdisk header is OK
2497 -12 common/image.c Ramdisk data has bad checksum
2498 11 common/image.c Ramdisk data has correct checksum
2499 12 common/image.c Ramdisk verification complete, start loading
2500 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2501 13 common/image.c Start multifile image verification
2502 14 common/image.c No initial ramdisk, no multifile, continue.
2504 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2506 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2507 -31 post/post.c POST test failed, detected by post_output_backlog()
2508 -32 post/post.c POST test failed, detected by post_run_single()
2510 34 common/cmd_doc.c before loading a Image from a DOC device
2511 -35 common/cmd_doc.c Bad usage of "doc" command
2512 35 common/cmd_doc.c correct usage of "doc" command
2513 -36 common/cmd_doc.c No boot device
2514 36 common/cmd_doc.c correct boot device
2515 -37 common/cmd_doc.c Unknown Chip ID on boot device
2516 37 common/cmd_doc.c correct chip ID found, device available
2517 -38 common/cmd_doc.c Read Error on boot device
2518 38 common/cmd_doc.c reading Image header from DOC device OK
2519 -39 common/cmd_doc.c Image header has bad magic number
2520 39 common/cmd_doc.c Image header has correct magic number
2521 -40 common/cmd_doc.c Error reading Image from DOC device
2522 40 common/cmd_doc.c Image header has correct magic number
2523 41 common/cmd_ide.c before loading a Image from a IDE device
2524 -42 common/cmd_ide.c Bad usage of "ide" command
2525 42 common/cmd_ide.c correct usage of "ide" command
2526 -43 common/cmd_ide.c No boot device
2527 43 common/cmd_ide.c boot device found
2528 -44 common/cmd_ide.c Device not available
2529 44 common/cmd_ide.c Device available
2530 -45 common/cmd_ide.c wrong partition selected
2531 45 common/cmd_ide.c partition selected
2532 -46 common/cmd_ide.c Unknown partition table
2533 46 common/cmd_ide.c valid partition table found
2534 -47 common/cmd_ide.c Invalid partition type
2535 47 common/cmd_ide.c correct partition type
2536 -48 common/cmd_ide.c Error reading Image Header on boot device
2537 48 common/cmd_ide.c reading Image Header from IDE device OK
2538 -49 common/cmd_ide.c Image header has bad magic number
2539 49 common/cmd_ide.c Image header has correct magic number
2540 -50 common/cmd_ide.c Image header has bad checksum
2541 50 common/cmd_ide.c Image header has correct checksum
2542 -51 common/cmd_ide.c Error reading Image from IDE device
2543 51 common/cmd_ide.c reading Image from IDE device OK
2544 52 common/cmd_nand.c before loading a Image from a NAND device
2545 -53 common/cmd_nand.c Bad usage of "nand" command
2546 53 common/cmd_nand.c correct usage of "nand" command
2547 -54 common/cmd_nand.c No boot device
2548 54 common/cmd_nand.c boot device found
2549 -55 common/cmd_nand.c Unknown Chip ID on boot device
2550 55 common/cmd_nand.c correct chip ID found, device available
2551 -56 common/cmd_nand.c Error reading Image Header on boot device
2552 56 common/cmd_nand.c reading Image Header from NAND device OK
2553 -57 common/cmd_nand.c Image header has bad magic number
2554 57 common/cmd_nand.c Image header has correct magic number
2555 -58 common/cmd_nand.c Error reading Image from NAND device
2556 58 common/cmd_nand.c reading Image from NAND device OK
2558 -60 common/env_common.c Environment has a bad CRC, using default
2560 64 net/eth.c starting with Ethernet configuration.
2561 -64 net/eth.c no Ethernet found.
2562 65 net/eth.c Ethernet found.
2564 -80 common/cmd_net.c usage wrong
2565 80 common/cmd_net.c before calling NetLoop()
2566 -81 common/cmd_net.c some error in NetLoop() occurred
2567 81 common/cmd_net.c NetLoop() back without error
2568 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2569 82 common/cmd_net.c trying automatic boot
2570 83 common/cmd_net.c running "source" command
2571 -83 common/cmd_net.c some error in automatic boot or "source" command
2572 84 common/cmd_net.c end without errors
2577 100 common/cmd_bootm.c Kernel FIT Image has correct format
2578 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2579 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2580 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2581 102 common/cmd_bootm.c Kernel unit name specified
2582 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2583 103 common/cmd_bootm.c Found configuration node
2584 104 common/cmd_bootm.c Got kernel subimage node offset
2585 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2586 105 common/cmd_bootm.c Kernel subimage hash verification OK
2587 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2588 106 common/cmd_bootm.c Architecture check OK
2589 -106 common/cmd_bootm.c Kernel subimage has wrong type
2590 107 common/cmd_bootm.c Kernel subimage type OK
2591 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2592 108 common/cmd_bootm.c Got kernel subimage data/size
2593 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2594 -109 common/cmd_bootm.c Can't get kernel subimage type
2595 -110 common/cmd_bootm.c Can't get kernel subimage comp
2596 -111 common/cmd_bootm.c Can't get kernel subimage os
2597 -112 common/cmd_bootm.c Can't get kernel subimage load address
2598 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2600 120 common/image.c Start initial ramdisk verification
2601 -120 common/image.c Ramdisk FIT image has incorrect format
2602 121 common/image.c Ramdisk FIT image has correct format
2603 122 common/image.c No ramdisk subimage unit name, using configuration
2604 -122 common/image.c Can't get configuration for ramdisk subimage
2605 123 common/image.c Ramdisk unit name specified
2606 -124 common/image.c Can't get ramdisk subimage node offset
2607 125 common/image.c Got ramdisk subimage node offset
2608 -125 common/image.c Ramdisk subimage hash verification failed
2609 126 common/image.c Ramdisk subimage hash verification OK
2610 -126 common/image.c Ramdisk subimage for unsupported architecture
2611 127 common/image.c Architecture check OK
2612 -127 common/image.c Can't get ramdisk subimage data/size
2613 128 common/image.c Got ramdisk subimage data/size
2614 129 common/image.c Can't get ramdisk load address
2615 -129 common/image.c Got ramdisk load address
2617 -130 common/cmd_doc.c Incorrect FIT image format
2618 131 common/cmd_doc.c FIT image format OK
2620 -140 common/cmd_ide.c Incorrect FIT image format
2621 141 common/cmd_ide.c FIT image format OK
2623 -150 common/cmd_nand.c Incorrect FIT image format
2624 151 common/cmd_nand.c FIT image format OK
2626 - FIT image support:
2628 Enable support for the FIT uImage format.
2630 CONFIG_FIT_BEST_MATCH
2631 When no configuration is explicitly selected, default to the
2632 one whose fdt's compatibility field best matches that of
2633 U-Boot itself. A match is considered "best" if it matches the
2634 most specific compatibility entry of U-Boot's fdt's root node.
2635 The order of entries in the configuration's fdt is ignored.
2637 - Standalone program support:
2638 CONFIG_STANDALONE_LOAD_ADDR
2640 This option defines a board specific value for the
2641 address where standalone program gets loaded, thus
2642 overwriting the architecture dependent default
2645 - Frame Buffer Address:
2648 Define CONFIG_FB_ADDR if you want to use specific
2649 address for frame buffer.
2650 Then system will reserve the frame buffer address to
2651 defined address instead of lcd_setmem (this function
2652 grabs the memory for frame buffer by panel's size).
2654 Please see board_init_f function.
2656 - Automatic software updates via TFTP server
2658 CONFIG_UPDATE_TFTP_CNT_MAX
2659 CONFIG_UPDATE_TFTP_MSEC_MAX
2661 These options enable and control the auto-update feature;
2662 for a more detailed description refer to doc/README.update.
2664 - MTD Support (mtdparts command, UBI support)
2667 Adds the MTD device infrastructure from the Linux kernel.
2668 Needed for mtdparts command support.
2670 CONFIG_MTD_PARTITIONS
2672 Adds the MTD partitioning infrastructure from the Linux
2673 kernel. Needed for UBI support.
2677 Enable building of SPL globally.
2680 LDSCRIPT for linking the SPL binary.
2683 Maximum binary size (text, data and rodata) of the SPL binary.
2685 CONFIG_SPL_TEXT_BASE
2686 TEXT_BASE for linking the SPL binary.
2688 CONFIG_SPL_RELOC_TEXT_BASE
2689 Address to relocate to. If unspecified, this is equal to
2690 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2692 CONFIG_SPL_BSS_START_ADDR
2693 Link address for the BSS within the SPL binary.
2695 CONFIG_SPL_BSS_MAX_SIZE
2696 Maximum binary size of the BSS section of the SPL binary.
2699 Adress of the start of the stack SPL will use
2701 CONFIG_SPL_RELOC_STACK
2702 Adress of the start of the stack SPL will use after
2703 relocation. If unspecified, this is equal to
2706 CONFIG_SYS_SPL_MALLOC_START
2707 Starting address of the malloc pool used in SPL.
2709 CONFIG_SYS_SPL_MALLOC_SIZE
2710 The size of the malloc pool used in SPL.
2712 CONFIG_SPL_FRAMEWORK
2713 Enable the SPL framework under common/. This framework
2714 supports MMC, NAND and YMODEM loading of U-Boot and NAND
2715 NAND loading of the Linux Kernel.
2717 CONFIG_SPL_DISPLAY_PRINT
2718 For ARM, enable an optional function to print more information
2719 about the running system.
2721 CONFIG_SPL_INIT_MINIMAL
2722 Arch init code should be built for a very small image
2724 CONFIG_SPL_LIBCOMMON_SUPPORT
2725 Support for common/libcommon.o in SPL binary
2727 CONFIG_SPL_LIBDISK_SUPPORT
2728 Support for disk/libdisk.o in SPL binary
2730 CONFIG_SPL_I2C_SUPPORT
2731 Support for drivers/i2c/libi2c.o in SPL binary
2733 CONFIG_SPL_GPIO_SUPPORT
2734 Support for drivers/gpio/libgpio.o in SPL binary
2736 CONFIG_SPL_MMC_SUPPORT
2737 Support for drivers/mmc/libmmc.o in SPL binary
2739 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
2740 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
2741 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
2742 Address, size and partition on the MMC to load U-Boot from
2743 when the MMC is being used in raw mode.
2745 CONFIG_SPL_FAT_SUPPORT
2746 Support for fs/fat/libfat.o in SPL binary
2748 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
2749 Filename to read to load U-Boot when reading from FAT
2751 CONFIG_SPL_NAND_BASE
2752 Include nand_base.c in the SPL. Requires
2753 CONFIG_SPL_NAND_DRIVERS.
2755 CONFIG_SPL_NAND_DRIVERS
2756 SPL uses normal NAND drivers, not minimal drivers.
2759 Include standard software ECC in the SPL
2761 CONFIG_SPL_NAND_SIMPLE
2762 Support for NAND boot using simple NAND drivers that
2763 expose the cmd_ctrl() interface.
2765 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2766 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2767 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2768 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2769 CONFIG_SYS_NAND_ECCBYTES
2770 Defines the size and behavior of the NAND that SPL uses
2773 CONFIG_SYS_NAND_U_BOOT_OFFS
2774 Location in NAND to read U-Boot from
2776 CONFIG_SYS_NAND_U_BOOT_DST
2777 Location in memory to load U-Boot to
2779 CONFIG_SYS_NAND_U_BOOT_SIZE
2780 Size of image to load
2782 CONFIG_SYS_NAND_U_BOOT_START
2783 Entry point in loaded image to jump to
2785 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2786 Define this if you need to first read the OOB and then the
2787 data. This is used for example on davinci plattforms.
2789 CONFIG_SPL_OMAP3_ID_NAND
2790 Support for an OMAP3-specific set of functions to return the
2791 ID and MFR of the first attached NAND chip, if present.
2793 CONFIG_SPL_SERIAL_SUPPORT
2794 Support for drivers/serial/libserial.o in SPL binary
2796 CONFIG_SPL_SPI_FLASH_SUPPORT
2797 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
2799 CONFIG_SPL_SPI_SUPPORT
2800 Support for drivers/spi/libspi.o in SPL binary
2802 CONFIG_SPL_RAM_DEVICE
2803 Support for running image already present in ram, in SPL binary
2805 CONFIG_SPL_LIBGENERIC_SUPPORT
2806 Support for lib/libgeneric.o in SPL binary
2809 Final target image containing SPL and payload. Some SPLs
2810 use an arch-specific makefile fragment instead, for
2811 example if more than one image needs to be produced.
2816 [so far only for SMDK2400 boards]
2818 - Modem support enable:
2819 CONFIG_MODEM_SUPPORT
2821 - RTS/CTS Flow control enable:
2824 - Modem debug support:
2825 CONFIG_MODEM_SUPPORT_DEBUG
2827 Enables debugging stuff (char screen[1024], dbg())
2828 for modem support. Useful only with BDI2000.
2830 - Interrupt support (PPC):
2832 There are common interrupt_init() and timer_interrupt()
2833 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2834 for CPU specific initialization. interrupt_init_cpu()
2835 should set decrementer_count to appropriate value. If
2836 CPU resets decrementer automatically after interrupt
2837 (ppc4xx) it should set decrementer_count to zero.
2838 timer_interrupt() calls timer_interrupt_cpu() for CPU
2839 specific handling. If board has watchdog / status_led
2840 / other_activity_monitor it works automatically from
2841 general timer_interrupt().
2845 In the target system modem support is enabled when a
2846 specific key (key combination) is pressed during
2847 power-on. Otherwise U-Boot will boot normally
2848 (autoboot). The key_pressed() function is called from
2849 board_init(). Currently key_pressed() is a dummy
2850 function, returning 1 and thus enabling modem
2853 If there are no modem init strings in the
2854 environment, U-Boot proceed to autoboot; the
2855 previous output (banner, info printfs) will be
2858 See also: doc/README.Modem
2860 Board initialization settings:
2861 ------------------------------
2863 During Initialization u-boot calls a number of board specific functions
2864 to allow the preparation of board specific prerequisites, e.g. pin setup
2865 before drivers are initialized. To enable these callbacks the
2866 following configuration macros have to be defined. Currently this is
2867 architecture specific, so please check arch/your_architecture/lib/board.c
2868 typically in board_init_f() and board_init_r().
2870 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2871 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2872 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
2873 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
2875 Configuration Settings:
2876 -----------------------
2878 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2879 undefine this when you're short of memory.
2881 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2882 width of the commands listed in the 'help' command output.
2884 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2885 prompt for user input.
2887 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2889 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2891 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2893 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2894 the application (usually a Linux kernel) when it is
2897 - CONFIG_SYS_BAUDRATE_TABLE:
2898 List of legal baudrate settings for this board.
2900 - CONFIG_SYS_CONSOLE_INFO_QUIET
2901 Suppress display of console information at boot.
2903 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2904 If the board specific function
2905 extern int overwrite_console (void);
2906 returns 1, the stdin, stderr and stdout are switched to the
2907 serial port, else the settings in the environment are used.
2909 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2910 Enable the call to overwrite_console().
2912 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2913 Enable overwrite of previous console environment settings.
2915 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2916 Begin and End addresses of the area used by the
2919 - CONFIG_SYS_ALT_MEMTEST:
2920 Enable an alternate, more extensive memory test.
2922 - CONFIG_SYS_MEMTEST_SCRATCH:
2923 Scratch address used by the alternate memory test
2924 You only need to set this if address zero isn't writeable
2926 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2927 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2928 this specified memory area will get subtracted from the top
2929 (end) of RAM and won't get "touched" at all by U-Boot. By
2930 fixing up gd->ram_size the Linux kernel should gets passed
2931 the now "corrected" memory size and won't touch it either.
2932 This should work for arch/ppc and arch/powerpc. Only Linux
2933 board ports in arch/powerpc with bootwrapper support that
2934 recalculate the memory size from the SDRAM controller setup
2935 will have to get fixed in Linux additionally.
2937 This option can be used as a workaround for the 440EPx/GRx
2938 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2941 WARNING: Please make sure that this value is a multiple of
2942 the Linux page size (normally 4k). If this is not the case,
2943 then the end address of the Linux memory will be located at a
2944 non page size aligned address and this could cause major
2947 - CONFIG_SYS_TFTP_LOADADDR:
2948 Default load address for network file downloads
2950 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2951 Enable temporary baudrate change while serial download
2953 - CONFIG_SYS_SDRAM_BASE:
2954 Physical start address of SDRAM. _Must_ be 0 here.
2956 - CONFIG_SYS_MBIO_BASE:
2957 Physical start address of Motherboard I/O (if using a
2960 - CONFIG_SYS_FLASH_BASE:
2961 Physical start address of Flash memory.
2963 - CONFIG_SYS_MONITOR_BASE:
2964 Physical start address of boot monitor code (set by
2965 make config files to be same as the text base address
2966 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2967 CONFIG_SYS_FLASH_BASE when booting from flash.
2969 - CONFIG_SYS_MONITOR_LEN:
2970 Size of memory reserved for monitor code, used to
2971 determine _at_compile_time_ (!) if the environment is
2972 embedded within the U-Boot image, or in a separate
2975 - CONFIG_SYS_MALLOC_LEN:
2976 Size of DRAM reserved for malloc() use.
2978 - CONFIG_SYS_BOOTM_LEN:
2979 Normally compressed uImages are limited to an
2980 uncompressed size of 8 MBytes. If this is not enough,
2981 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2982 to adjust this setting to your needs.
2984 - CONFIG_SYS_BOOTMAPSZ:
2985 Maximum size of memory mapped by the startup code of
2986 the Linux kernel; all data that must be processed by
2987 the Linux kernel (bd_info, boot arguments, FDT blob if
2988 used) must be put below this limit, unless "bootm_low"
2989 enviroment variable is defined and non-zero. In such case
2990 all data for the Linux kernel must be between "bootm_low"
2991 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2992 variable "bootm_mapsize" will override the value of
2993 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2994 then the value in "bootm_size" will be used instead.
2996 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2997 Enable initrd_high functionality. If defined then the
2998 initrd_high feature is enabled and the bootm ramdisk subcommand
3001 - CONFIG_SYS_BOOT_GET_CMDLINE:
3002 Enables allocating and saving kernel cmdline in space between
3003 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3005 - CONFIG_SYS_BOOT_GET_KBD:
3006 Enables allocating and saving a kernel copy of the bd_info in
3007 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3009 - CONFIG_SYS_MAX_FLASH_BANKS:
3010 Max number of Flash memory banks
3012 - CONFIG_SYS_MAX_FLASH_SECT:
3013 Max number of sectors on a Flash chip
3015 - CONFIG_SYS_FLASH_ERASE_TOUT:
3016 Timeout for Flash erase operations (in ms)
3018 - CONFIG_SYS_FLASH_WRITE_TOUT:
3019 Timeout for Flash write operations (in ms)
3021 - CONFIG_SYS_FLASH_LOCK_TOUT
3022 Timeout for Flash set sector lock bit operation (in ms)
3024 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3025 Timeout for Flash clear lock bits operation (in ms)
3027 - CONFIG_SYS_FLASH_PROTECTION
3028 If defined, hardware flash sectors protection is used
3029 instead of U-Boot software protection.
3031 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3033 Enable TFTP transfers directly to flash memory;
3034 without this option such a download has to be
3035 performed in two steps: (1) download to RAM, and (2)
3036 copy from RAM to flash.
3038 The two-step approach is usually more reliable, since
3039 you can check if the download worked before you erase
3040 the flash, but in some situations (when system RAM is
3041 too limited to allow for a temporary copy of the
3042 downloaded image) this option may be very useful.
3044 - CONFIG_SYS_FLASH_CFI:
3045 Define if the flash driver uses extra elements in the
3046 common flash structure for storing flash geometry.
3048 - CONFIG_FLASH_CFI_DRIVER
3049 This option also enables the building of the cfi_flash driver
3050 in the drivers directory
3052 - CONFIG_FLASH_CFI_MTD
3053 This option enables the building of the cfi_mtd driver
3054 in the drivers directory. The driver exports CFI flash
3057 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3058 Use buffered writes to flash.
3060 - CONFIG_FLASH_SPANSION_S29WS_N
3061 s29ws-n MirrorBit flash has non-standard addresses for buffered
3064 - CONFIG_SYS_FLASH_QUIET_TEST
3065 If this option is defined, the common CFI flash doesn't
3066 print it's warning upon not recognized FLASH banks. This
3067 is useful, if some of the configured banks are only
3068 optionally available.
3070 - CONFIG_FLASH_SHOW_PROGRESS
3071 If defined (must be an integer), print out countdown
3072 digits and dots. Recommended value: 45 (9..1) for 80
3073 column displays, 15 (3..1) for 40 column displays.
3075 - CONFIG_SYS_RX_ETH_BUFFER:
3076 Defines the number of Ethernet receive buffers. On some
3077 Ethernet controllers it is recommended to set this value
3078 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3079 buffers can be full shortly after enabling the interface
3080 on high Ethernet traffic.
3081 Defaults to 4 if not defined.
3083 - CONFIG_ENV_MAX_ENTRIES
3085 Maximum number of entries in the hash table that is used
3086 internally to store the environment settings. The default
3087 setting is supposed to be generous and should work in most
3088 cases. This setting can be used to tune behaviour; see
3089 lib/hashtable.c for details.
3091 The following definitions that deal with the placement and management
3092 of environment data (variable area); in general, we support the
3093 following configurations:
3095 - CONFIG_BUILD_ENVCRC:
3097 Builds up envcrc with the target environment so that external utils
3098 may easily extract it and embed it in final U-Boot images.
3100 - CONFIG_ENV_IS_IN_FLASH:
3102 Define this if the environment is in flash memory.
3104 a) The environment occupies one whole flash sector, which is
3105 "embedded" in the text segment with the U-Boot code. This
3106 happens usually with "bottom boot sector" or "top boot
3107 sector" type flash chips, which have several smaller
3108 sectors at the start or the end. For instance, such a
3109 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3110 such a case you would place the environment in one of the
3111 4 kB sectors - with U-Boot code before and after it. With
3112 "top boot sector" type flash chips, you would put the
3113 environment in one of the last sectors, leaving a gap
3114 between U-Boot and the environment.
3116 - CONFIG_ENV_OFFSET:
3118 Offset of environment data (variable area) to the
3119 beginning of flash memory; for instance, with bottom boot
3120 type flash chips the second sector can be used: the offset
3121 for this sector is given here.
3123 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3127 This is just another way to specify the start address of
3128 the flash sector containing the environment (instead of
3131 - CONFIG_ENV_SECT_SIZE:
3133 Size of the sector containing the environment.
3136 b) Sometimes flash chips have few, equal sized, BIG sectors.
3137 In such a case you don't want to spend a whole sector for
3142 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3143 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3144 of this flash sector for the environment. This saves
3145 memory for the RAM copy of the environment.
3147 It may also save flash memory if you decide to use this
3148 when your environment is "embedded" within U-Boot code,
3149 since then the remainder of the flash sector could be used
3150 for U-Boot code. It should be pointed out that this is
3151 STRONGLY DISCOURAGED from a robustness point of view:
3152 updating the environment in flash makes it always
3153 necessary to erase the WHOLE sector. If something goes
3154 wrong before the contents has been restored from a copy in
3155 RAM, your target system will be dead.
3157 - CONFIG_ENV_ADDR_REDUND
3158 CONFIG_ENV_SIZE_REDUND
3160 These settings describe a second storage area used to hold
3161 a redundant copy of the environment data, so that there is
3162 a valid backup copy in case there is a power failure during
3163 a "saveenv" operation.
3165 BE CAREFUL! Any changes to the flash layout, and some changes to the
3166 source code will make it necessary to adapt <board>/u-boot.lds*
3170 - CONFIG_ENV_IS_IN_NVRAM:
3172 Define this if you have some non-volatile memory device
3173 (NVRAM, battery buffered SRAM) which you want to use for the
3179 These two #defines are used to determine the memory area you
3180 want to use for environment. It is assumed that this memory
3181 can just be read and written to, without any special
3184 BE CAREFUL! The first access to the environment happens quite early
3185 in U-Boot initalization (when we try to get the setting of for the
3186 console baudrate). You *MUST* have mapped your NVRAM area then, or
3189 Please note that even with NVRAM we still use a copy of the
3190 environment in RAM: we could work on NVRAM directly, but we want to
3191 keep settings there always unmodified except somebody uses "saveenv"
3192 to save the current settings.
3195 - CONFIG_ENV_IS_IN_EEPROM:
3197 Use this if you have an EEPROM or similar serial access
3198 device and a driver for it.
3200 - CONFIG_ENV_OFFSET:
3203 These two #defines specify the offset and size of the
3204 environment area within the total memory of your EEPROM.
3206 - CONFIG_SYS_I2C_EEPROM_ADDR:
3207 If defined, specified the chip address of the EEPROM device.
3208 The default address is zero.
3210 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3211 If defined, the number of bits used to address bytes in a
3212 single page in the EEPROM device. A 64 byte page, for example
3213 would require six bits.
3215 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3216 If defined, the number of milliseconds to delay between
3217 page writes. The default is zero milliseconds.
3219 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3220 The length in bytes of the EEPROM memory array address. Note
3221 that this is NOT the chip address length!
3223 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3224 EEPROM chips that implement "address overflow" are ones
3225 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3226 address and the extra bits end up in the "chip address" bit
3227 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3230 Note that we consider the length of the address field to
3231 still be one byte because the extra address bits are hidden
3232 in the chip address.
3234 - CONFIG_SYS_EEPROM_SIZE:
3235 The size in bytes of the EEPROM device.
3237 - CONFIG_ENV_EEPROM_IS_ON_I2C
3238 define this, if you have I2C and SPI activated, and your
3239 EEPROM, which holds the environment, is on the I2C bus.
3241 - CONFIG_I2C_ENV_EEPROM_BUS
3242 if you have an Environment on an EEPROM reached over
3243 I2C muxes, you can define here, how to reach this
3244 EEPROM. For example:
3246 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
3248 EEPROM which holds the environment, is reached over
3249 a pca9547 i2c mux with address 0x70, channel 3.
3251 - CONFIG_ENV_IS_IN_DATAFLASH:
3253 Define this if you have a DataFlash memory device which you
3254 want to use for the environment.
3256 - CONFIG_ENV_OFFSET:
3260 These three #defines specify the offset and size of the
3261 environment area within the total memory of your DataFlash placed
3262 at the specified address.
3264 - CONFIG_ENV_IS_IN_REMOTE:
3266 Define this if you have a remote memory space which you
3267 want to use for the local device's environment.
3272 These two #defines specify the address and size of the
3273 environment area within the remote memory space. The
3274 local device can get the environment from remote memory
3275 space by SRIO or PCIE links.
3277 BE CAREFUL! For some special cases, the local device can not use
3278 "saveenv" command. For example, the local device will get the
3279 environment stored in a remote NOR flash by SRIO or PCIE link,
3280 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3282 - CONFIG_ENV_IS_IN_NAND:
3284 Define this if you have a NAND device which you want to use
3285 for the environment.
3287 - CONFIG_ENV_OFFSET:
3290 These two #defines specify the offset and size of the environment
3291 area within the first NAND device. CONFIG_ENV_OFFSET must be
3292 aligned to an erase block boundary.
3294 - CONFIG_ENV_OFFSET_REDUND (optional):
3296 This setting describes a second storage area of CONFIG_ENV_SIZE
3297 size used to hold a redundant copy of the environment data, so
3298 that there is a valid backup copy in case there is a power failure
3299 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3300 aligned to an erase block boundary.
3302 - CONFIG_ENV_RANGE (optional):
3304 Specifies the length of the region in which the environment
3305 can be written. This should be a multiple of the NAND device's
3306 block size. Specifying a range with more erase blocks than
3307 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3308 the range to be avoided.
3310 - CONFIG_ENV_OFFSET_OOB (optional):
3312 Enables support for dynamically retrieving the offset of the
3313 environment from block zero's out-of-band data. The
3314 "nand env.oob" command can be used to record this offset.
3315 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3316 using CONFIG_ENV_OFFSET_OOB.
3318 - CONFIG_NAND_ENV_DST
3320 Defines address in RAM to which the nand_spl code should copy the
3321 environment. If redundant environment is used, it will be copied to
3322 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3324 - CONFIG_SYS_SPI_INIT_OFFSET
3326 Defines offset to the initial SPI buffer area in DPRAM. The
3327 area is used at an early stage (ROM part) if the environment
3328 is configured to reside in the SPI EEPROM: We need a 520 byte
3329 scratch DPRAM area. It is used between the two initialization
3330 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3331 to be a good choice since it makes it far enough from the
3332 start of the data area as well as from the stack pointer.
3334 Please note that the environment is read-only until the monitor
3335 has been relocated to RAM and a RAM copy of the environment has been
3336 created; also, when using EEPROM you will have to use getenv_f()
3337 until then to read environment variables.
3339 The environment is protected by a CRC32 checksum. Before the monitor
3340 is relocated into RAM, as a result of a bad CRC you will be working
3341 with the compiled-in default environment - *silently*!!! [This is
3342 necessary, because the first environment variable we need is the
3343 "baudrate" setting for the console - if we have a bad CRC, we don't
3344 have any device yet where we could complain.]
3346 Note: once the monitor has been relocated, then it will complain if
3347 the default environment is used; a new CRC is computed as soon as you
3348 use the "saveenv" command to store a valid environment.
3350 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3351 Echo the inverted Ethernet link state to the fault LED.
3353 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3354 also needs to be defined.
3356 - CONFIG_SYS_FAULT_MII_ADDR:
3357 MII address of the PHY to check for the Ethernet link state.
3359 - CONFIG_NS16550_MIN_FUNCTIONS:
3360 Define this if you desire to only have use of the NS16550_init
3361 and NS16550_putc functions for the serial driver located at
3362 drivers/serial/ns16550.c. This option is useful for saving
3363 space for already greatly restricted images, including but not
3364 limited to NAND_SPL configurations.
3366 Low Level (hardware related) configuration options:
3367 ---------------------------------------------------
3369 - CONFIG_SYS_CACHELINE_SIZE:
3370 Cache Line Size of the CPU.
3372 - CONFIG_SYS_DEFAULT_IMMR:
3373 Default address of the IMMR after system reset.
3375 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3376 and RPXsuper) to be able to adjust the position of
3377 the IMMR register after a reset.
3379 - CONFIG_SYS_CCSRBAR_DEFAULT:
3380 Default (power-on reset) physical address of CCSR on Freescale
3383 - CONFIG_SYS_CCSRBAR:
3384 Virtual address of CCSR. On a 32-bit build, this is typically
3385 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3387 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3388 for cross-platform code that uses that macro instead.
3390 - CONFIG_SYS_CCSRBAR_PHYS:
3391 Physical address of CCSR. CCSR can be relocated to a new
3392 physical address, if desired. In this case, this macro should
3393 be set to that address. Otherwise, it should be set to the
3394 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3395 is typically relocated on 36-bit builds. It is recommended
3396 that this macro be defined via the _HIGH and _LOW macros:
3398 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3399 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3401 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3402 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3403 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3404 used in assembly code, so it must not contain typecasts or
3405 integer size suffixes (e.g. "ULL").
3407 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3408 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3409 used in assembly code, so it must not contain typecasts or
3410 integer size suffixes (e.g. "ULL").
3412 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3413 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3414 forced to a value that ensures that CCSR is not relocated.
3416 - Floppy Disk Support:
3417 CONFIG_SYS_FDC_DRIVE_NUMBER
3419 the default drive number (default value 0)
3421 CONFIG_SYS_ISA_IO_STRIDE
3423 defines the spacing between FDC chipset registers
3426 CONFIG_SYS_ISA_IO_OFFSET
3428 defines the offset of register from address. It
3429 depends on which part of the data bus is connected to
3430 the FDC chipset. (default value 0)
3432 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3433 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3436 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3437 fdc_hw_init() is called at the beginning of the FDC
3438 setup. fdc_hw_init() must be provided by the board
3439 source code. It is used to make hardware dependant
3443 Most IDE controllers were designed to be connected with PCI
3444 interface. Only few of them were designed for AHB interface.
3445 When software is doing ATA command and data transfer to
3446 IDE devices through IDE-AHB controller, some additional
3447 registers accessing to these kind of IDE-AHB controller
3450 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3451 DO NOT CHANGE unless you know exactly what you're
3452 doing! (11-4) [MPC8xx/82xx systems only]
3454 - CONFIG_SYS_INIT_RAM_ADDR:
3456 Start address of memory area that can be used for
3457 initial data and stack; please note that this must be
3458 writable memory that is working WITHOUT special
3459 initialization, i. e. you CANNOT use normal RAM which
3460 will become available only after programming the
3461 memory controller and running certain initialization
3464 U-Boot uses the following memory types:
3465 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3466 - MPC824X: data cache
3467 - PPC4xx: data cache
3469 - CONFIG_SYS_GBL_DATA_OFFSET:
3471 Offset of the initial data structure in the memory
3472 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3473 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3474 data is located at the end of the available space
3475 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3476 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
3477 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3478 CONFIG_SYS_GBL_DATA_OFFSET) downward.
3481 On the MPC824X (or other systems that use the data
3482 cache for initial memory) the address chosen for
3483 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3484 point to an otherwise UNUSED address space between
3485 the top of RAM and the start of the PCI space.
3487 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
3489 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
3491 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
3493 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
3495 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
3497 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
3499 - CONFIG_SYS_OR_TIMING_SDRAM:
3502 - CONFIG_SYS_MAMR_PTA:
3503 periodic timer for refresh
3505 - CONFIG_SYS_DER: Debug Event Register (37-47)
3507 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3508 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3509 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3510 CONFIG_SYS_BR1_PRELIM:
3511 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3513 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
3514 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3515 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3516 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3518 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
3519 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
3520 Machine Mode Register and Memory Periodic Timer
3521 Prescaler definitions (SDRAM timing)
3523 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
3524 enable I2C microcode relocation patch (MPC8xx);
3525 define relocation offset in DPRAM [DSP2]
3527 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
3528 enable SMC microcode relocation patch (MPC8xx);
3529 define relocation offset in DPRAM [SMC1]
3531 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
3532 enable SPI microcode relocation patch (MPC8xx);
3533 define relocation offset in DPRAM [SCC4]
3535 - CONFIG_SYS_USE_OSCCLK:
3536 Use OSCM clock mode on MBX8xx board. Be careful,
3537 wrong setting might damage your board. Read
3538 doc/README.MBX before setting this variable!
3540 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
3541 Offset of the bootmode word in DPRAM used by post
3542 (Power On Self Tests). This definition overrides
3543 #define'd default value in commproc.h resp.
3546 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
3547 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
3548 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
3549 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
3550 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
3551 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
3552 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
3553 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
3554 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
3556 - CONFIG_PCI_DISABLE_PCIE:
3557 Disable PCI-Express on systems where it is supported but not
3560 - CONFIG_PCI_ENUM_ONLY
3561 Only scan through and get the devices on the busses.
3562 Don't do any setup work, presumably because someone or
3563 something has already done it, and we don't need to do it
3564 a second time. Useful for platforms that are pre-booted
3565 by coreboot or similar.
3568 Chip has SRIO or not
3571 Board has SRIO 1 port available
3574 Board has SRIO 2 port available
3576 - CONFIG_SYS_SRIOn_MEM_VIRT:
3577 Virtual Address of SRIO port 'n' memory region
3579 - CONFIG_SYS_SRIOn_MEM_PHYS:
3580 Physical Address of SRIO port 'n' memory region
3582 - CONFIG_SYS_SRIOn_MEM_SIZE:
3583 Size of SRIO port 'n' memory region
3585 - CONFIG_SYS_NDFC_16
3586 Defined to tell the NDFC that the NAND chip is using a
3589 - CONFIG_SYS_NDFC_EBC0_CFG
3590 Sets the EBC0_CFG register for the NDFC. If not defined
3591 a default value will be used.
3594 Get DDR timing information from an I2C EEPROM. Common
3595 with pluggable memory modules such as SODIMMs
3598 I2C address of the SPD EEPROM
3600 - CONFIG_SYS_SPD_BUS_NUM
3601 If SPD EEPROM is on an I2C bus other than the first
3602 one, specify here. Note that the value must resolve
3603 to something your driver can deal with.
3605 - CONFIG_SYS_DDR_RAW_TIMING
3606 Get DDR timing information from other than SPD. Common with
3607 soldered DDR chips onboard without SPD. DDR raw timing
3608 parameters are extracted from datasheet and hard-coded into
3609 header files or board specific files.
3611 - CONFIG_FSL_DDR_INTERACTIVE
3612 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3614 - CONFIG_SYS_83XX_DDR_USES_CS0
3615 Only for 83xx systems. If specified, then DDR should
3616 be configured using CS0 and CS1 instead of CS2 and CS3.
3618 - CONFIG_ETHER_ON_FEC[12]
3619 Define to enable FEC[12] on a 8xx series processor.
3621 - CONFIG_FEC[12]_PHY
3622 Define to the hardcoded PHY address which corresponds
3623 to the given FEC; i. e.
3624 #define CONFIG_FEC1_PHY 4
3625 means that the PHY with address 4 is connected to FEC1
3627 When set to -1, means to probe for first available.
3629 - CONFIG_FEC[12]_PHY_NORXERR
3630 The PHY does not have a RXERR line (RMII only).
3631 (so program the FEC to ignore it).
3634 Enable RMII mode for all FECs.
3635 Note that this is a global option, we can't
3636 have one FEC in standard MII mode and another in RMII mode.
3638 - CONFIG_CRC32_VERIFY
3639 Add a verify option to the crc32 command.
3642 => crc32 -v <address> <count> <crc32>
3644 Where address/count indicate a memory area
3645 and crc32 is the correct crc32 which the
3649 Add the "loopw" memory command. This only takes effect if
3650 the memory commands are activated globally (CONFIG_CMD_MEM).
3653 Add the "mdc" and "mwc" memory commands. These are cyclic
3658 This command will print 4 bytes (10,11,12,13) each 500 ms.
3660 => mwc.l 100 12345678 10
3661 This command will write 12345678 to address 100 all 10 ms.
3663 This only takes effect if the memory commands are activated
3664 globally (CONFIG_CMD_MEM).
3666 - CONFIG_SKIP_LOWLEVEL_INIT
3667 [ARM, NDS32, MIPS only] If this variable is defined, then certain
3668 low level initializations (like setting up the memory
3669 controller) are omitted and/or U-Boot does not
3670 relocate itself into RAM.
3672 Normally this variable MUST NOT be defined. The only
3673 exception is when U-Boot is loaded (to RAM) by some
3674 other boot loader or by a debugger which performs
3675 these initializations itself.
3678 Modifies the behaviour of start.S when compiling a loader
3679 that is executed before the actual U-Boot. E.g. when
3680 compiling a NAND SPL.
3682 - CONFIG_USE_ARCH_MEMCPY
3683 CONFIG_USE_ARCH_MEMSET
3684 If these options are used a optimized version of memcpy/memset will
3685 be used if available. These functions may be faster under some
3686 conditions but may increase the binary size.
3688 - CONFIG_X86_NO_RESET_VECTOR
3689 If defined, the x86 reset vector code is excluded. You will need
3690 to do this when U-Boot is running from Coreboot.
3692 - CONFIG_X86_NO_REAL_MODE
3693 If defined, x86 real mode code is omitted. This assumes a
3694 32-bit environment where such code is not needed. You will
3695 need to do this when U-Boot is running from Coreboot.
3698 Freescale QE/FMAN Firmware Support:
3699 -----------------------------------
3701 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3702 loading of "firmware", which is encoded in the QE firmware binary format.
3703 This firmware often needs to be loaded during U-Boot booting, so macros
3704 are used to identify the storage device (NOR flash, SPI, etc) and the address
3707 - CONFIG_SYS_QE_FMAN_FW_ADDR
3708 The address in the storage device where the firmware is located. The
3709 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3712 - CONFIG_SYS_QE_FMAN_FW_LENGTH
3713 The maximum possible size of the firmware. The firmware binary format
3714 has a field that specifies the actual size of the firmware, but it
3715 might not be possible to read any part of the firmware unless some
3716 local storage is allocated to hold the entire firmware first.
3718 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
3719 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3720 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3721 virtual address in NOR flash.
3723 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
3724 Specifies that QE/FMAN firmware is located in NAND flash.
3725 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3727 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
3728 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3729 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3731 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
3732 Specifies that QE/FMAN firmware is located on the primary SPI
3733 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3735 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3736 Specifies that QE/FMAN firmware is located in the remote (master)
3737 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
3738 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3739 window->master inbound window->master LAW->the ucode address in
3740 master's memory space.
3742 Building the Software:
3743 ======================
3745 Building U-Boot has been tested in several native build environments
3746 and in many different cross environments. Of course we cannot support
3747 all possibly existing versions of cross development tools in all
3748 (potentially obsolete) versions. In case of tool chain problems we
3749 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3750 which is extensively used to build and test U-Boot.
3752 If you are not using a native environment, it is assumed that you
3753 have GNU cross compiling tools available in your path. In this case,
3754 you must set the environment variable CROSS_COMPILE in your shell.
3755 Note that no changes to the Makefile or any other source files are
3756 necessary. For example using the ELDK on a 4xx CPU, please enter:
3758 $ CROSS_COMPILE=ppc_4xx-
3759 $ export CROSS_COMPILE
3761 Note: If you wish to generate Windows versions of the utilities in
3762 the tools directory you can use the MinGW toolchain
3763 (http://www.mingw.org). Set your HOST tools to the MinGW
3764 toolchain and execute 'make tools'. For example:
3766 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3768 Binaries such as tools/mkimage.exe will be created which can
3769 be executed on computers running Windows.
3771 U-Boot is intended to be simple to build. After installing the
3772 sources you must configure U-Boot for one specific board type. This
3777 where "NAME_config" is the name of one of the existing configu-
3778 rations; see boards.cfg for supported names.
3780 Note: for some board special configuration names may exist; check if
3781 additional information is available from the board vendor; for
3782 instance, the TQM823L systems are available without (standard)
3783 or with LCD support. You can select such additional "features"
3784 when choosing the configuration, i. e.
3787 - will configure for a plain TQM823L, i. e. no LCD support
3789 make TQM823L_LCD_config
3790 - will configure for a TQM823L with U-Boot console on LCD
3795 Finally, type "make all", and you should get some working U-Boot
3796 images ready for download to / installation on your system:
3798 - "u-boot.bin" is a raw binary image
3799 - "u-boot" is an image in ELF binary format
3800 - "u-boot.srec" is in Motorola S-Record format
3802 By default the build is performed locally and the objects are saved
3803 in the source directory. One of the two methods can be used to change
3804 this behavior and build U-Boot to some external directory:
3806 1. Add O= to the make command line invocations:
3808 make O=/tmp/build distclean
3809 make O=/tmp/build NAME_config
3810 make O=/tmp/build all
3812 2. Set environment variable BUILD_DIR to point to the desired location:
3814 export BUILD_DIR=/tmp/build
3819 Note that the command line "O=" setting overrides the BUILD_DIR environment
3823 Please be aware that the Makefiles assume you are using GNU make, so
3824 for instance on NetBSD you might need to use "gmake" instead of
3828 If the system board that you have is not listed, then you will need
3829 to port U-Boot to your hardware platform. To do this, follow these
3832 1. Add a new configuration option for your board to the toplevel
3833 "boards.cfg" file, using the existing entries as examples.
3834 Follow the instructions there to keep the boards in order.
3835 2. Create a new directory to hold your board specific code. Add any
3836 files you need. In your board directory, you will need at least
3837 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3838 3. Create a new configuration file "include/configs/<board>.h" for
3840 3. If you're porting U-Boot to a new CPU, then also create a new
3841 directory to hold your CPU specific code. Add any files you need.
3842 4. Run "make <board>_config" with your new name.
3843 5. Type "make", and you should get a working "u-boot.srec" file
3844 to be installed on your target system.
3845 6. Debug and solve any problems that might arise.
3846 [Of course, this last step is much harder than it sounds.]
3849 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3850 ==============================================================
3852 If you have modified U-Boot sources (for instance added a new board
3853 or support for new devices, a new CPU, etc.) you are expected to
3854 provide feedback to the other developers. The feedback normally takes
3855 the form of a "patch", i. e. a context diff against a certain (latest
3856 official or latest in the git repository) version of U-Boot sources.
3858 But before you submit such a patch, please verify that your modifi-
3859 cation did not break existing code. At least make sure that *ALL* of
3860 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3861 just run the "MAKEALL" script, which will configure and build U-Boot
3862 for ALL supported system. Be warned, this will take a while. You can
3863 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3864 environment variable to the script, i. e. to use the ELDK cross tools
3867 CROSS_COMPILE=ppc_8xx- MAKEALL
3869 or to build on a native PowerPC system you can type
3871 CROSS_COMPILE=' ' MAKEALL
3873 When using the MAKEALL script, the default behaviour is to build
3874 U-Boot in the source directory. This location can be changed by
3875 setting the BUILD_DIR environment variable. Also, for each target
3876 built, the MAKEALL script saves two log files (<target>.ERR and
3877 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3878 location can be changed by setting the MAKEALL_LOGDIR environment
3879 variable. For example:
3881 export BUILD_DIR=/tmp/build
3882 export MAKEALL_LOGDIR=/tmp/log
3883 CROSS_COMPILE=ppc_8xx- MAKEALL
3885 With the above settings build objects are saved in the /tmp/build,
3886 log files are saved in the /tmp/log and the source tree remains clean
3887 during the whole build process.
3890 See also "U-Boot Porting Guide" below.
3893 Monitor Commands - Overview:
3894 ============================
3896 go - start application at address 'addr'
3897 run - run commands in an environment variable
3898 bootm - boot application image from memory
3899 bootp - boot image via network using BootP/TFTP protocol
3900 bootz - boot zImage from memory
3901 tftpboot- boot image via network using TFTP protocol
3902 and env variables "ipaddr" and "serverip"
3903 (and eventually "gatewayip")
3904 tftpput - upload a file via network using TFTP protocol
3905 rarpboot- boot image via network using RARP/TFTP protocol
3906 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3907 loads - load S-Record file over serial line
3908 loadb - load binary file over serial line (kermit mode)
3910 mm - memory modify (auto-incrementing)
3911 nm - memory modify (constant address)
3912 mw - memory write (fill)
3914 cmp - memory compare
3915 crc32 - checksum calculation
3916 i2c - I2C sub-system
3917 sspi - SPI utility commands
3918 base - print or set address offset
3919 printenv- print environment variables
3920 setenv - set environment variables
3921 saveenv - save environment variables to persistent storage
3922 protect - enable or disable FLASH write protection
3923 erase - erase FLASH memory
3924 flinfo - print FLASH memory information
3925 nand - NAND memory operations (see doc/README.nand)
3926 bdinfo - print Board Info structure
3927 iminfo - print header information for application image
3928 coninfo - print console devices and informations
3929 ide - IDE sub-system
3930 loop - infinite loop on address range
3931 loopw - infinite write loop on address range
3932 mtest - simple RAM test
3933 icache - enable or disable instruction cache
3934 dcache - enable or disable data cache
3935 reset - Perform RESET of the CPU
3936 echo - echo args to console
3937 version - print monitor version
3938 help - print online help
3939 ? - alias for 'help'
3942 Monitor Commands - Detailed Description:
3943 ========================================
3947 For now: just type "help <command>".
3950 Environment Variables:
3951 ======================
3953 U-Boot supports user configuration using Environment Variables which
3954 can be made persistent by saving to Flash memory.
3956 Environment Variables are set using "setenv", printed using
3957 "printenv", and saved to Flash using "saveenv". Using "setenv"
3958 without a value can be used to delete a variable from the
3959 environment. As long as you don't save the environment you are
3960 working with an in-memory copy. In case the Flash area containing the
3961 environment is erased by accident, a default environment is provided.
3963 Some configuration options can be set using Environment Variables.
3965 List of environment variables (most likely not complete):
3967 baudrate - see CONFIG_BAUDRATE
3969 bootdelay - see CONFIG_BOOTDELAY
3971 bootcmd - see CONFIG_BOOTCOMMAND
3973 bootargs - Boot arguments when booting an RTOS image
3975 bootfile - Name of the image to load with TFTP
3977 bootm_low - Memory range available for image processing in the bootm
3978 command can be restricted. This variable is given as
3979 a hexadecimal number and defines lowest address allowed
3980 for use by the bootm command. See also "bootm_size"
3981 environment variable. Address defined by "bootm_low" is
3982 also the base of the initial memory mapping for the Linux
3983 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3986 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3987 This variable is given as a hexadecimal number and it
3988 defines the size of the memory region starting at base
3989 address bootm_low that is accessible by the Linux kernel
3990 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3991 as the default value if it is defined, and bootm_size is
3994 bootm_size - Memory range available for image processing in the bootm
3995 command can be restricted. This variable is given as
3996 a hexadecimal number and defines the size of the region
3997 allowed for use by the bootm command. See also "bootm_low"
3998 environment variable.
4000 updatefile - Location of the software update file on a TFTP server, used
4001 by the automatic software update feature. Please refer to
4002 documentation in doc/README.update for more details.
4004 autoload - if set to "no" (any string beginning with 'n'),
4005 "bootp" will just load perform a lookup of the
4006 configuration from the BOOTP server, but not try to
4007 load any image using TFTP
4009 autostart - if set to "yes", an image loaded using the "bootp",
4010 "rarpboot", "tftpboot" or "diskboot" commands will
4011 be automatically started (by internally calling
4014 If set to "no", a standalone image passed to the
4015 "bootm" command will be copied to the load address
4016 (and eventually uncompressed), but NOT be started.
4017 This can be used to load and uncompress arbitrary
4020 fdt_high - if set this restricts the maximum address that the
4021 flattened device tree will be copied into upon boot.
4022 For example, if you have a system with 1 GB memory
4023 at physical address 0x10000000, while Linux kernel
4024 only recognizes the first 704 MB as low memory, you
4025 may need to set fdt_high as 0x3C000000 to have the
4026 device tree blob be copied to the maximum address
4027 of the 704 MB low memory, so that Linux kernel can
4028 access it during the boot procedure.
4030 If this is set to the special value 0xFFFFFFFF then
4031 the fdt will not be copied at all on boot. For this
4032 to work it must reside in writable memory, have
4033 sufficient padding on the end of it for u-boot to
4034 add the information it needs into it, and the memory
4035 must be accessible by the kernel.
4037 fdtcontroladdr- if set this is the address of the control flattened
4038 device tree used by U-Boot when CONFIG_OF_CONTROL is
4041 i2cfast - (PPC405GP|PPC405EP only)
4042 if set to 'y' configures Linux I2C driver for fast
4043 mode (400kHZ). This environment variable is used in
4044 initialization code. So, for changes to be effective
4045 it must be saved and board must be reset.
4047 initrd_high - restrict positioning of initrd images:
4048 If this variable is not set, initrd images will be
4049 copied to the highest possible address in RAM; this
4050 is usually what you want since it allows for
4051 maximum initrd size. If for some reason you want to
4052 make sure that the initrd image is loaded below the
4053 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4054 variable to a value of "no" or "off" or "0".
4055 Alternatively, you can set it to a maximum upper
4056 address to use (U-Boot will still check that it
4057 does not overwrite the U-Boot stack and data).
4059 For instance, when you have a system with 16 MB
4060 RAM, and want to reserve 4 MB from use by Linux,
4061 you can do this by adding "mem=12M" to the value of
4062 the "bootargs" variable. However, now you must make
4063 sure that the initrd image is placed in the first
4064 12 MB as well - this can be done with
4066 setenv initrd_high 00c00000
4068 If you set initrd_high to 0xFFFFFFFF, this is an
4069 indication to U-Boot that all addresses are legal
4070 for the Linux kernel, including addresses in flash
4071 memory. In this case U-Boot will NOT COPY the
4072 ramdisk at all. This may be useful to reduce the
4073 boot time on your system, but requires that this
4074 feature is supported by your Linux kernel.
4076 ipaddr - IP address; needed for tftpboot command
4078 loadaddr - Default load address for commands like "bootp",
4079 "rarpboot", "tftpboot", "loadb" or "diskboot"
4081 loads_echo - see CONFIG_LOADS_ECHO
4083 serverip - TFTP server IP address; needed for tftpboot command
4085 bootretry - see CONFIG_BOOT_RETRY_TIME
4087 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4089 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4091 ethprime - controls which interface is used first.
4093 ethact - controls which interface is currently active.
4094 For example you can do the following
4096 => setenv ethact FEC
4097 => ping 192.168.0.1 # traffic sent on FEC
4098 => setenv ethact SCC
4099 => ping 10.0.0.1 # traffic sent on SCC
4101 ethrotate - When set to "no" U-Boot does not go through all
4102 available network interfaces.
4103 It just stays at the currently selected interface.
4105 netretry - When set to "no" each network operation will
4106 either succeed or fail without retrying.
4107 When set to "once" the network operation will
4108 fail when all the available network interfaces
4109 are tried once without success.
4110 Useful on scripts which control the retry operation
4113 npe_ucode - set load address for the NPE microcode
4115 tftpsrcport - If this is set, the value is used for TFTP's
4118 tftpdstport - If this is set, the value is used for TFTP's UDP
4119 destination port instead of the Well Know Port 69.
4121 tftpblocksize - Block size to use for TFTP transfers; if not set,
4122 we use the TFTP server's default block size
4124 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4125 seconds, minimum value is 1000 = 1 second). Defines
4126 when a packet is considered to be lost so it has to
4127 be retransmitted. The default is 5000 = 5 seconds.
4128 Lowering this value may make downloads succeed
4129 faster in networks with high packet loss rates or
4130 with unreliable TFTP servers.
4132 vlan - When set to a value < 4095 the traffic over
4133 Ethernet is encapsulated/received over 802.1q
4136 The following image location variables contain the location of images
4137 used in booting. The "Image" column gives the role of the image and is
4138 not an environment variable name. The other columns are environment
4139 variable names. "File Name" gives the name of the file on a TFTP
4140 server, "RAM Address" gives the location in RAM the image will be
4141 loaded to, and "Flash Location" gives the image's address in NOR
4142 flash or offset in NAND flash.
4144 *Note* - these variables don't have to be defined for all boards, some
4145 boards currenlty use other variables for these purposes, and some
4146 boards use these variables for other purposes.
4148 Image File Name RAM Address Flash Location
4149 ----- --------- ----------- --------------
4150 u-boot u-boot u-boot_addr_r u-boot_addr
4151 Linux kernel bootfile kernel_addr_r kernel_addr
4152 device tree blob fdtfile fdt_addr_r fdt_addr
4153 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4155 The following environment variables may be used and automatically
4156 updated by the network boot commands ("bootp" and "rarpboot"),
4157 depending the information provided by your boot server:
4159 bootfile - see above
4160 dnsip - IP address of your Domain Name Server
4161 dnsip2 - IP address of your secondary Domain Name Server
4162 gatewayip - IP address of the Gateway (Router) to use
4163 hostname - Target hostname
4165 netmask - Subnet Mask
4166 rootpath - Pathname of the root filesystem on the NFS server
4167 serverip - see above
4170 There are two special Environment Variables:
4172 serial# - contains hardware identification information such
4173 as type string and/or serial number
4174 ethaddr - Ethernet address
4176 These variables can be set only once (usually during manufacturing of
4177 the board). U-Boot refuses to delete or overwrite these variables
4178 once they have been set once.
4181 Further special Environment Variables:
4183 ver - Contains the U-Boot version string as printed
4184 with the "version" command. This variable is
4185 readonly (see CONFIG_VERSION_VARIABLE).
4188 Please note that changes to some configuration parameters may take
4189 only effect after the next boot (yes, that's just like Windoze :-).
4192 Command Line Parsing:
4193 =====================
4195 There are two different command line parsers available with U-Boot:
4196 the old "simple" one, and the much more powerful "hush" shell:
4198 Old, simple command line parser:
4199 --------------------------------
4201 - supports environment variables (through setenv / saveenv commands)
4202 - several commands on one line, separated by ';'
4203 - variable substitution using "... ${name} ..." syntax
4204 - special characters ('$', ';') can be escaped by prefixing with '\',
4206 setenv bootcmd bootm \${address}
4207 - You can also escape text by enclosing in single apostrophes, for example:
4208 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4213 - similar to Bourne shell, with control structures like
4214 if...then...else...fi, for...do...done; while...do...done,
4215 until...do...done, ...
4216 - supports environment ("global") variables (through setenv / saveenv
4217 commands) and local shell variables (through standard shell syntax
4218 "name=value"); only environment variables can be used with "run"
4224 (1) If a command line (or an environment variable executed by a "run"
4225 command) contains several commands separated by semicolon, and
4226 one of these commands fails, then the remaining commands will be
4229 (2) If you execute several variables with one call to run (i. e.
4230 calling run with a list of variables as arguments), any failing
4231 command will cause "run" to terminate, i. e. the remaining
4232 variables are not executed.
4234 Note for Redundant Ethernet Interfaces:
4235 =======================================
4237 Some boards come with redundant Ethernet interfaces; U-Boot supports
4238 such configurations and is capable of automatic selection of a
4239 "working" interface when needed. MAC assignment works as follows:
4241 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4242 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4243 "eth1addr" (=>eth1), "eth2addr", ...
4245 If the network interface stores some valid MAC address (for instance
4246 in SROM), this is used as default address if there is NO correspon-
4247 ding setting in the environment; if the corresponding environment
4248 variable is set, this overrides the settings in the card; that means:
4250 o If the SROM has a valid MAC address, and there is no address in the
4251 environment, the SROM's address is used.
4253 o If there is no valid address in the SROM, and a definition in the
4254 environment exists, then the value from the environment variable is
4257 o If both the SROM and the environment contain a MAC address, and
4258 both addresses are the same, this MAC address is used.
4260 o If both the SROM and the environment contain a MAC address, and the
4261 addresses differ, the value from the environment is used and a
4264 o If neither SROM nor the environment contain a MAC address, an error
4267 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4268 will be programmed into hardware as part of the initialization process. This
4269 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4270 The naming convention is as follows:
4271 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4276 U-Boot is capable of booting (and performing other auxiliary operations on)
4277 images in two formats:
4279 New uImage format (FIT)
4280 -----------------------
4282 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4283 to Flattened Device Tree). It allows the use of images with multiple
4284 components (several kernels, ramdisks, etc.), with contents protected by
4285 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4291 Old image format is based on binary files which can be basically anything,
4292 preceded by a special header; see the definitions in include/image.h for
4293 details; basically, the header defines the following image properties:
4295 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4296 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4297 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4298 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4300 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4301 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4302 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4303 * Compression Type (uncompressed, gzip, bzip2)
4309 The header is marked by a special Magic Number, and both the header
4310 and the data portions of the image are secured against corruption by
4317 Although U-Boot should support any OS or standalone application
4318 easily, the main focus has always been on Linux during the design of
4321 U-Boot includes many features that so far have been part of some
4322 special "boot loader" code within the Linux kernel. Also, any
4323 "initrd" images to be used are no longer part of one big Linux image;
4324 instead, kernel and "initrd" are separate images. This implementation
4325 serves several purposes:
4327 - the same features can be used for other OS or standalone
4328 applications (for instance: using compressed images to reduce the
4329 Flash memory footprint)
4331 - it becomes much easier to port new Linux kernel versions because
4332 lots of low-level, hardware dependent stuff are done by U-Boot
4334 - the same Linux kernel image can now be used with different "initrd"
4335 images; of course this also means that different kernel images can
4336 be run with the same "initrd". This makes testing easier (you don't
4337 have to build a new "zImage.initrd" Linux image when you just
4338 change a file in your "initrd"). Also, a field-upgrade of the
4339 software is easier now.
4345 Porting Linux to U-Boot based systems:
4346 ---------------------------------------
4348 U-Boot cannot save you from doing all the necessary modifications to
4349 configure the Linux device drivers for use with your target hardware
4350 (no, we don't intend to provide a full virtual machine interface to
4353 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4355 Just make sure your machine specific header file (for instance
4356 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4357 Information structure as we define in include/asm-<arch>/u-boot.h,
4358 and make sure that your definition of IMAP_ADDR uses the same value
4359 as your U-Boot configuration in CONFIG_SYS_IMMR.
4362 Configuring the Linux kernel:
4363 -----------------------------
4365 No specific requirements for U-Boot. Make sure you have some root
4366 device (initial ramdisk, NFS) for your target system.
4369 Building a Linux Image:
4370 -----------------------
4372 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4373 not used. If you use recent kernel source, a new build target
4374 "uImage" will exist which automatically builds an image usable by
4375 U-Boot. Most older kernels also have support for a "pImage" target,
4376 which was introduced for our predecessor project PPCBoot and uses a
4377 100% compatible format.
4386 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4387 encapsulate a compressed Linux kernel image with header information,
4388 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4390 * build a standard "vmlinux" kernel image (in ELF binary format):
4392 * convert the kernel into a raw binary image:
4394 ${CROSS_COMPILE}-objcopy -O binary \
4395 -R .note -R .comment \
4396 -S vmlinux linux.bin
4398 * compress the binary image:
4402 * package compressed binary image for U-Boot:
4404 mkimage -A ppc -O linux -T kernel -C gzip \
4405 -a 0 -e 0 -n "Linux Kernel Image" \
4406 -d linux.bin.gz uImage
4409 The "mkimage" tool can also be used to create ramdisk images for use
4410 with U-Boot, either separated from the Linux kernel image, or
4411 combined into one file. "mkimage" encapsulates the images with a 64
4412 byte header containing information about target architecture,
4413 operating system, image type, compression method, entry points, time
4414 stamp, CRC32 checksums, etc.
4416 "mkimage" can be called in two ways: to verify existing images and
4417 print the header information, or to build new images.
4419 In the first form (with "-l" option) mkimage lists the information
4420 contained in the header of an existing U-Boot image; this includes
4421 checksum verification:
4423 tools/mkimage -l image
4424 -l ==> list image header information
4426 The second form (with "-d" option) is used to build a U-Boot image
4427 from a "data file" which is used as image payload:
4429 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4430 -n name -d data_file image
4431 -A ==> set architecture to 'arch'
4432 -O ==> set operating system to 'os'
4433 -T ==> set image type to 'type'
4434 -C ==> set compression type 'comp'
4435 -a ==> set load address to 'addr' (hex)
4436 -e ==> set entry point to 'ep' (hex)
4437 -n ==> set image name to 'name'
4438 -d ==> use image data from 'datafile'
4440 Right now, all Linux kernels for PowerPC systems use the same load
4441 address (0x00000000), but the entry point address depends on the
4444 - 2.2.x kernels have the entry point at 0x0000000C,
4445 - 2.3.x and later kernels have the entry point at 0x00000000.
4447 So a typical call to build a U-Boot image would read:
4449 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4450 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4451 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
4452 > examples/uImage.TQM850L
4453 Image Name: 2.4.4 kernel for TQM850L
4454 Created: Wed Jul 19 02:34:59 2000
4455 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4456 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4457 Load Address: 0x00000000
4458 Entry Point: 0x00000000
4460 To verify the contents of the image (or check for corruption):
4462 -> tools/mkimage -l examples/uImage.TQM850L
4463 Image Name: 2.4.4 kernel for TQM850L
4464 Created: Wed Jul 19 02:34:59 2000
4465 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4466 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4467 Load Address: 0x00000000
4468 Entry Point: 0x00000000
4470 NOTE: for embedded systems where boot time is critical you can trade
4471 speed for memory and install an UNCOMPRESSED image instead: this
4472 needs more space in Flash, but boots much faster since it does not
4473 need to be uncompressed:
4475 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
4476 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4477 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4478 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
4479 > examples/uImage.TQM850L-uncompressed
4480 Image Name: 2.4.4 kernel for TQM850L
4481 Created: Wed Jul 19 02:34:59 2000
4482 Image Type: PowerPC Linux Kernel Image (uncompressed)
4483 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4484 Load Address: 0x00000000
4485 Entry Point: 0x00000000
4488 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4489 when your kernel is intended to use an initial ramdisk:
4491 -> tools/mkimage -n 'Simple Ramdisk Image' \
4492 > -A ppc -O linux -T ramdisk -C gzip \
4493 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4494 Image Name: Simple Ramdisk Image
4495 Created: Wed Jan 12 14:01:50 2000
4496 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4497 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4498 Load Address: 0x00000000
4499 Entry Point: 0x00000000
4502 Installing a Linux Image:
4503 -------------------------
4505 To downloading a U-Boot image over the serial (console) interface,
4506 you must convert the image to S-Record format:
4508 objcopy -I binary -O srec examples/image examples/image.srec
4510 The 'objcopy' does not understand the information in the U-Boot
4511 image header, so the resulting S-Record file will be relative to
4512 address 0x00000000. To load it to a given address, you need to
4513 specify the target address as 'offset' parameter with the 'loads'
4516 Example: install the image to address 0x40100000 (which on the
4517 TQM8xxL is in the first Flash bank):
4519 => erase 40100000 401FFFFF
4525 ## Ready for S-Record download ...
4526 ~>examples/image.srec
4527 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4529 15989 15990 15991 15992
4530 [file transfer complete]
4532 ## Start Addr = 0x00000000
4535 You can check the success of the download using the 'iminfo' command;
4536 this includes a checksum verification so you can be sure no data
4537 corruption happened:
4541 ## Checking Image at 40100000 ...
4542 Image Name: 2.2.13 for initrd on TQM850L
4543 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4544 Data Size: 335725 Bytes = 327 kB = 0 MB
4545 Load Address: 00000000
4546 Entry Point: 0000000c
4547 Verifying Checksum ... OK
4553 The "bootm" command is used to boot an application that is stored in
4554 memory (RAM or Flash). In case of a Linux kernel image, the contents
4555 of the "bootargs" environment variable is passed to the kernel as
4556 parameters. You can check and modify this variable using the
4557 "printenv" and "setenv" commands:
4560 => printenv bootargs
4561 bootargs=root=/dev/ram
4563 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4565 => printenv bootargs
4566 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4569 ## Booting Linux kernel at 40020000 ...
4570 Image Name: 2.2.13 for NFS on TQM850L
4571 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4572 Data Size: 381681 Bytes = 372 kB = 0 MB
4573 Load Address: 00000000
4574 Entry Point: 0000000c
4575 Verifying Checksum ... OK
4576 Uncompressing Kernel Image ... OK
4577 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
4578 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4579 time_init: decrementer frequency = 187500000/60
4580 Calibrating delay loop... 49.77 BogoMIPS
4581 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4584 If you want to boot a Linux kernel with initial RAM disk, you pass
4585 the memory addresses of both the kernel and the initrd image (PPBCOOT
4586 format!) to the "bootm" command:
4588 => imi 40100000 40200000
4590 ## Checking Image at 40100000 ...
4591 Image Name: 2.2.13 for initrd on TQM850L
4592 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4593 Data Size: 335725 Bytes = 327 kB = 0 MB
4594 Load Address: 00000000
4595 Entry Point: 0000000c
4596 Verifying Checksum ... OK
4598 ## Checking Image at 40200000 ...
4599 Image Name: Simple Ramdisk Image
4600 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4601 Data Size: 566530 Bytes = 553 kB = 0 MB
4602 Load Address: 00000000
4603 Entry Point: 00000000
4604 Verifying Checksum ... OK
4606 => bootm 40100000 40200000
4607 ## Booting Linux kernel at 40100000 ...
4608 Image Name: 2.2.13 for initrd on TQM850L
4609 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4610 Data Size: 335725 Bytes = 327 kB = 0 MB
4611 Load Address: 00000000
4612 Entry Point: 0000000c
4613 Verifying Checksum ... OK
4614 Uncompressing Kernel Image ... OK
4615 ## Loading RAMDisk Image at 40200000 ...
4616 Image Name: Simple Ramdisk Image
4617 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4618 Data Size: 566530 Bytes = 553 kB = 0 MB
4619 Load Address: 00000000
4620 Entry Point: 00000000
4621 Verifying Checksum ... OK
4622 Loading Ramdisk ... OK
4623 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
4624 Boot arguments: root=/dev/ram
4625 time_init: decrementer frequency = 187500000/60
4626 Calibrating delay loop... 49.77 BogoMIPS
4628 RAMDISK: Compressed image found at block 0
4629 VFS: Mounted root (ext2 filesystem).
4633 Boot Linux and pass a flat device tree:
4636 First, U-Boot must be compiled with the appropriate defines. See the section
4637 titled "Linux Kernel Interface" above for a more in depth explanation. The
4638 following is an example of how to start a kernel and pass an updated
4644 oft=oftrees/mpc8540ads.dtb
4645 => tftp $oftaddr $oft
4646 Speed: 1000, full duplex
4648 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4649 Filename 'oftrees/mpc8540ads.dtb'.
4650 Load address: 0x300000
4653 Bytes transferred = 4106 (100a hex)
4654 => tftp $loadaddr $bootfile
4655 Speed: 1000, full duplex
4657 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4659 Load address: 0x200000
4660 Loading:############
4662 Bytes transferred = 1029407 (fb51f hex)
4667 => bootm $loadaddr - $oftaddr
4668 ## Booting image at 00200000 ...
4669 Image Name: Linux-2.6.17-dirty
4670 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4671 Data Size: 1029343 Bytes = 1005.2 kB
4672 Load Address: 00000000
4673 Entry Point: 00000000
4674 Verifying Checksum ... OK
4675 Uncompressing Kernel Image ... OK
4676 Booting using flat device tree at 0x300000
4677 Using MPC85xx ADS machine description
4678 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4682 More About U-Boot Image Types:
4683 ------------------------------
4685 U-Boot supports the following image types:
4687 "Standalone Programs" are directly runnable in the environment
4688 provided by U-Boot; it is expected that (if they behave
4689 well) you can continue to work in U-Boot after return from
4690 the Standalone Program.
4691 "OS Kernel Images" are usually images of some Embedded OS which
4692 will take over control completely. Usually these programs
4693 will install their own set of exception handlers, device
4694 drivers, set up the MMU, etc. - this means, that you cannot
4695 expect to re-enter U-Boot except by resetting the CPU.
4696 "RAMDisk Images" are more or less just data blocks, and their
4697 parameters (address, size) are passed to an OS kernel that is
4699 "Multi-File Images" contain several images, typically an OS
4700 (Linux) kernel image and one or more data images like
4701 RAMDisks. This construct is useful for instance when you want
4702 to boot over the network using BOOTP etc., where the boot
4703 server provides just a single image file, but you want to get
4704 for instance an OS kernel and a RAMDisk image.
4706 "Multi-File Images" start with a list of image sizes, each
4707 image size (in bytes) specified by an "uint32_t" in network
4708 byte order. This list is terminated by an "(uint32_t)0".
4709 Immediately after the terminating 0 follow the images, one by
4710 one, all aligned on "uint32_t" boundaries (size rounded up to
4711 a multiple of 4 bytes).
4713 "Firmware Images" are binary images containing firmware (like
4714 U-Boot or FPGA images) which usually will be programmed to
4717 "Script files" are command sequences that will be executed by
4718 U-Boot's command interpreter; this feature is especially
4719 useful when you configure U-Boot to use a real shell (hush)
4720 as command interpreter.
4722 Booting the Linux zImage:
4723 -------------------------
4725 On some platforms, it's possible to boot Linux zImage. This is done
4726 using the "bootz" command. The syntax of "bootz" command is the same
4727 as the syntax of "bootm" command.
4729 Note, defining the CONFIG_SUPPORT_INITRD_RAW allows user to supply
4730 kernel with raw initrd images. The syntax is slightly different, the
4731 address of the initrd must be augmented by it's size, in the following
4732 format: "<initrd addres>:<initrd size>".
4738 One of the features of U-Boot is that you can dynamically load and
4739 run "standalone" applications, which can use some resources of
4740 U-Boot like console I/O functions or interrupt services.
4742 Two simple examples are included with the sources:
4747 'examples/hello_world.c' contains a small "Hello World" Demo
4748 application; it is automatically compiled when you build U-Boot.
4749 It's configured to run at address 0x00040004, so you can play with it
4753 ## Ready for S-Record download ...
4754 ~>examples/hello_world.srec
4755 1 2 3 4 5 6 7 8 9 10 11 ...
4756 [file transfer complete]
4758 ## Start Addr = 0x00040004
4760 => go 40004 Hello World! This is a test.
4761 ## Starting application at 0x00040004 ...
4772 Hit any key to exit ...
4774 ## Application terminated, rc = 0x0
4776 Another example, which demonstrates how to register a CPM interrupt
4777 handler with the U-Boot code, can be found in 'examples/timer.c'.
4778 Here, a CPM timer is set up to generate an interrupt every second.
4779 The interrupt service routine is trivial, just printing a '.'
4780 character, but this is just a demo program. The application can be
4781 controlled by the following keys:
4783 ? - print current values og the CPM Timer registers
4784 b - enable interrupts and start timer
4785 e - stop timer and disable interrupts
4786 q - quit application
4789 ## Ready for S-Record download ...
4790 ~>examples/timer.srec
4791 1 2 3 4 5 6 7 8 9 10 11 ...
4792 [file transfer complete]
4794 ## Start Addr = 0x00040004
4797 ## Starting application at 0x00040004 ...
4800 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4803 [q, b, e, ?] Set interval 1000000 us
4806 [q, b, e, ?] ........
4807 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4810 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4813 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4816 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4818 [q, b, e, ?] ...Stopping timer
4820 [q, b, e, ?] ## Application terminated, rc = 0x0
4826 Over time, many people have reported problems when trying to use the
4827 "minicom" terminal emulation program for serial download. I (wd)
4828 consider minicom to be broken, and recommend not to use it. Under
4829 Unix, I recommend to use C-Kermit for general purpose use (and
4830 especially for kermit binary protocol download ("loadb" command), and
4831 use "cu" for S-Record download ("loads" command). See
4832 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4833 for help with kermit.
4836 Nevertheless, if you absolutely want to use it try adding this
4837 configuration to your "File transfer protocols" section:
4839 Name Program Name U/D FullScr IO-Red. Multi
4840 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4841 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4847 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4848 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4850 Building requires a cross environment; it is known to work on
4851 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4852 need gmake since the Makefiles are not compatible with BSD make).
4853 Note that the cross-powerpc package does not install include files;
4854 attempting to build U-Boot will fail because <machine/ansi.h> is
4855 missing. This file has to be installed and patched manually:
4857 # cd /usr/pkg/cross/powerpc-netbsd/include
4859 # ln -s powerpc machine
4860 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4861 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4863 Native builds *don't* work due to incompatibilities between native
4864 and U-Boot include files.
4866 Booting assumes that (the first part of) the image booted is a
4867 stage-2 loader which in turn loads and then invokes the kernel
4868 proper. Loader sources will eventually appear in the NetBSD source
4869 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4870 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4873 Implementation Internals:
4874 =========================
4876 The following is not intended to be a complete description of every
4877 implementation detail. However, it should help to understand the
4878 inner workings of U-Boot and make it easier to port it to custom
4882 Initial Stack, Global Data:
4883 ---------------------------
4885 The implementation of U-Boot is complicated by the fact that U-Boot
4886 starts running out of ROM (flash memory), usually without access to
4887 system RAM (because the memory controller is not initialized yet).
4888 This means that we don't have writable Data or BSS segments, and BSS
4889 is not initialized as zero. To be able to get a C environment working
4890 at all, we have to allocate at least a minimal stack. Implementation
4891 options for this are defined and restricted by the CPU used: Some CPU
4892 models provide on-chip memory (like the IMMR area on MPC8xx and
4893 MPC826x processors), on others (parts of) the data cache can be
4894 locked as (mis-) used as memory, etc.
4896 Chris Hallinan posted a good summary of these issues to the
4897 U-Boot mailing list:
4899 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4900 From: "Chris Hallinan" <clh@net1plus.com>
4901 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4904 Correct me if I'm wrong, folks, but the way I understand it
4905 is this: Using DCACHE as initial RAM for Stack, etc, does not
4906 require any physical RAM backing up the cache. The cleverness
4907 is that the cache is being used as a temporary supply of
4908 necessary storage before the SDRAM controller is setup. It's
4909 beyond the scope of this list to explain the details, but you
4910 can see how this works by studying the cache architecture and
4911 operation in the architecture and processor-specific manuals.
4913 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4914 is another option for the system designer to use as an
4915 initial stack/RAM area prior to SDRAM being available. Either
4916 option should work for you. Using CS 4 should be fine if your
4917 board designers haven't used it for something that would
4918 cause you grief during the initial boot! It is frequently not
4921 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4922 with your processor/board/system design. The default value
4923 you will find in any recent u-boot distribution in
4924 walnut.h should work for you. I'd set it to a value larger
4925 than your SDRAM module. If you have a 64MB SDRAM module, set
4926 it above 400_0000. Just make sure your board has no resources
4927 that are supposed to respond to that address! That code in
4928 start.S has been around a while and should work as is when
4929 you get the config right.
4934 It is essential to remember this, since it has some impact on the C
4935 code for the initialization procedures:
4937 * Initialized global data (data segment) is read-only. Do not attempt
4940 * Do not use any uninitialized global data (or implicitely initialized
4941 as zero data - BSS segment) at all - this is undefined, initiali-
4942 zation is performed later (when relocating to RAM).
4944 * Stack space is very limited. Avoid big data buffers or things like
4947 Having only the stack as writable memory limits means we cannot use
4948 normal global data to share information beween the code. But it
4949 turned out that the implementation of U-Boot can be greatly
4950 simplified by making a global data structure (gd_t) available to all
4951 functions. We could pass a pointer to this data as argument to _all_
4952 functions, but this would bloat the code. Instead we use a feature of
4953 the GCC compiler (Global Register Variables) to share the data: we
4954 place a pointer (gd) to the global data into a register which we
4955 reserve for this purpose.
4957 When choosing a register for such a purpose we are restricted by the
4958 relevant (E)ABI specifications for the current architecture, and by
4959 GCC's implementation.
4961 For PowerPC, the following registers have specific use:
4963 R2: reserved for system use
4964 R3-R4: parameter passing and return values
4965 R5-R10: parameter passing
4966 R13: small data area pointer
4970 (U-Boot also uses R12 as internal GOT pointer. r12
4971 is a volatile register so r12 needs to be reset when
4972 going back and forth between asm and C)
4974 ==> U-Boot will use R2 to hold a pointer to the global data
4976 Note: on PPC, we could use a static initializer (since the
4977 address of the global data structure is known at compile time),
4978 but it turned out that reserving a register results in somewhat
4979 smaller code - although the code savings are not that big (on
4980 average for all boards 752 bytes for the whole U-Boot image,
4981 624 text + 127 data).
4983 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4984 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4986 ==> U-Boot will use P3 to hold a pointer to the global data
4988 On ARM, the following registers are used:
4990 R0: function argument word/integer result
4991 R1-R3: function argument word
4993 R10: stack limit (used only if stack checking if enabled)
4994 R11: argument (frame) pointer
4995 R12: temporary workspace
4998 R15: program counter
5000 ==> U-Boot will use R8 to hold a pointer to the global data
5002 On Nios II, the ABI is documented here:
5003 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5005 ==> U-Boot will use gp to hold a pointer to the global data
5007 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5008 to access small data sections, so gp is free.
5010 On NDS32, the following registers are used:
5012 R0-R1: argument/return
5014 R15: temporary register for assembler
5015 R16: trampoline register
5016 R28: frame pointer (FP)
5017 R29: global pointer (GP)
5018 R30: link register (LP)
5019 R31: stack pointer (SP)
5020 PC: program counter (PC)
5022 ==> U-Boot will use R10 to hold a pointer to the global data
5024 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5025 or current versions of GCC may "optimize" the code too much.
5030 U-Boot runs in system state and uses physical addresses, i.e. the
5031 MMU is not used either for address mapping nor for memory protection.
5033 The available memory is mapped to fixed addresses using the memory
5034 controller. In this process, a contiguous block is formed for each
5035 memory type (Flash, SDRAM, SRAM), even when it consists of several
5036 physical memory banks.
5038 U-Boot is installed in the first 128 kB of the first Flash bank (on
5039 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5040 booting and sizing and initializing DRAM, the code relocates itself
5041 to the upper end of DRAM. Immediately below the U-Boot code some
5042 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5043 configuration setting]. Below that, a structure with global Board
5044 Info data is placed, followed by the stack (growing downward).
5046 Additionally, some exception handler code is copied to the low 8 kB
5047 of DRAM (0x00000000 ... 0x00001FFF).
5049 So a typical memory configuration with 16 MB of DRAM could look like
5052 0x0000 0000 Exception Vector code
5055 0x0000 2000 Free for Application Use
5061 0x00FB FF20 Monitor Stack (Growing downward)
5062 0x00FB FFAC Board Info Data and permanent copy of global data
5063 0x00FC 0000 Malloc Arena
5066 0x00FE 0000 RAM Copy of Monitor Code
5067 ... eventually: LCD or video framebuffer
5068 ... eventually: pRAM (Protected RAM - unchanged by reset)
5069 0x00FF FFFF [End of RAM]
5072 System Initialization:
5073 ----------------------
5075 In the reset configuration, U-Boot starts at the reset entry point
5076 (on most PowerPC systems at address 0x00000100). Because of the reset
5077 configuration for CS0# this is a mirror of the onboard Flash memory.
5078 To be able to re-map memory U-Boot then jumps to its link address.
5079 To be able to implement the initialization code in C, a (small!)
5080 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5081 which provide such a feature like MPC8xx or MPC8260), or in a locked
5082 part of the data cache. After that, U-Boot initializes the CPU core,
5083 the caches and the SIU.
5085 Next, all (potentially) available memory banks are mapped using a
5086 preliminary mapping. For example, we put them on 512 MB boundaries
5087 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5088 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5089 programmed for SDRAM access. Using the temporary configuration, a
5090 simple memory test is run that determines the size of the SDRAM
5093 When there is more than one SDRAM bank, and the banks are of
5094 different size, the largest is mapped first. For equal size, the first
5095 bank (CS2#) is mapped first. The first mapping is always for address
5096 0x00000000, with any additional banks following immediately to create
5097 contiguous memory starting from 0.
5099 Then, the monitor installs itself at the upper end of the SDRAM area
5100 and allocates memory for use by malloc() and for the global Board
5101 Info data; also, the exception vector code is copied to the low RAM
5102 pages, and the final stack is set up.
5104 Only after this relocation will you have a "normal" C environment;
5105 until that you are restricted in several ways, mostly because you are
5106 running from ROM, and because the code will have to be relocated to a
5110 U-Boot Porting Guide:
5111 ----------------------
5113 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5117 int main(int argc, char *argv[])
5119 sighandler_t no_more_time;
5121 signal(SIGALRM, no_more_time);
5122 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5124 if (available_money > available_manpower) {
5125 Pay consultant to port U-Boot;
5129 Download latest U-Boot source;
5131 Subscribe to u-boot mailing list;
5134 email("Hi, I am new to U-Boot, how do I get started?");
5137 Read the README file in the top level directory;
5138 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5139 Read applicable doc/*.README;
5140 Read the source, Luke;
5141 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5144 if (available_money > toLocalCurrency ($2500))
5147 Add a lot of aggravation and time;
5149 if (a similar board exists) { /* hopefully... */
5150 cp -a board/<similar> board/<myboard>
5151 cp include/configs/<similar>.h include/configs/<myboard>.h
5153 Create your own board support subdirectory;
5154 Create your own board include/configs/<myboard>.h file;
5156 Edit new board/<myboard> files
5157 Edit new include/configs/<myboard>.h
5162 Add / modify source code;
5166 email("Hi, I am having problems...");
5168 Send patch file to the U-Boot email list;
5169 if (reasonable critiques)
5170 Incorporate improvements from email list code review;
5172 Defend code as written;
5178 void no_more_time (int sig)
5187 All contributions to U-Boot should conform to the Linux kernel
5188 coding style; see the file "Documentation/CodingStyle" and the script
5189 "scripts/Lindent" in your Linux kernel source directory.
5191 Source files originating from a different project (for example the
5192 MTD subsystem) are generally exempt from these guidelines and are not
5193 reformated to ease subsequent migration to newer versions of those
5196 Please note that U-Boot is implemented in C (and to some small parts in
5197 Assembler); no C++ is used, so please do not use C++ style comments (//)
5200 Please also stick to the following formatting rules:
5201 - remove any trailing white space
5202 - use TAB characters for indentation and vertical alignment, not spaces
5203 - make sure NOT to use DOS '\r\n' line feeds
5204 - do not add more than 2 consecutive empty lines to source files
5205 - do not add trailing empty lines to source files
5207 Submissions which do not conform to the standards may be returned
5208 with a request to reformat the changes.
5214 Since the number of patches for U-Boot is growing, we need to
5215 establish some rules. Submissions which do not conform to these rules
5216 may be rejected, even when they contain important and valuable stuff.
5218 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5220 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5221 see http://lists.denx.de/mailman/listinfo/u-boot
5223 When you send a patch, please include the following information with
5226 * For bug fixes: a description of the bug and how your patch fixes
5227 this bug. Please try to include a way of demonstrating that the
5228 patch actually fixes something.
5230 * For new features: a description of the feature and your
5233 * A CHANGELOG entry as plaintext (separate from the patch)
5235 * For major contributions, your entry to the CREDITS file
5237 * When you add support for a new board, don't forget to add this
5238 board to the MAINTAINERS file, too.
5240 * If your patch adds new configuration options, don't forget to
5241 document these in the README file.
5243 * The patch itself. If you are using git (which is *strongly*
5244 recommended) you can easily generate the patch using the
5245 "git format-patch". If you then use "git send-email" to send it to
5246 the U-Boot mailing list, you will avoid most of the common problems
5247 with some other mail clients.
5249 If you cannot use git, use "diff -purN OLD NEW". If your version of
5250 diff does not support these options, then get the latest version of
5253 The current directory when running this command shall be the parent
5254 directory of the U-Boot source tree (i. e. please make sure that
5255 your patch includes sufficient directory information for the
5258 We prefer patches as plain text. MIME attachments are discouraged,
5259 and compressed attachments must not be used.
5261 * If one logical set of modifications affects or creates several
5262 files, all these changes shall be submitted in a SINGLE patch file.
5264 * Changesets that contain different, unrelated modifications shall be
5265 submitted as SEPARATE patches, one patch per changeset.
5270 * Before sending the patch, run the MAKEALL script on your patched
5271 source tree and make sure that no errors or warnings are reported
5272 for any of the boards.
5274 * Keep your modifications to the necessary minimum: A patch
5275 containing several unrelated changes or arbitrary reformats will be
5276 returned with a request to re-formatting / split it.
5278 * If you modify existing code, make sure that your new code does not
5279 add to the memory footprint of the code ;-) Small is beautiful!
5280 When adding new features, these should compile conditionally only
5281 (using #ifdef), and the resulting code with the new feature
5282 disabled must not need more memory than the old code without your
5285 * Remember that there is a size limit of 100 kB per message on the
5286 u-boot mailing list. Bigger patches will be moderated. If they are
5287 reasonable and not too big, they will be acknowledged. But patches
5288 bigger than the size limit should be avoided.
projects / kernel / u-boot.git / blob