2 # (C) Copyright 2000 - 2009
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
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
129 Starting with the release in October 2008, the names of the releases
130 were changed from numerical release numbers without deeper meaning
131 into a time stamp based numbering. Regular releases are identified by
132 names consisting of the calendar year and month of the release date.
133 Additional fields (if present) indicate release candidates or bug fix
134 releases in "stable" maintenance trees.
137 U-Boot v2009.11 - Release November 2009
138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
145 /arch Architecture specific files
146 /arm Files generic to ARM architecture
147 /cpu CPU specific files
148 /arm720t Files specific to ARM 720 CPUs
149 /arm920t Files specific to ARM 920 CPUs
150 /at91rm9200 Files specific to Atmel AT91RM9200 CPU
151 /imx Files specific to Freescale MC9328 i.MX CPUs
152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
153 /arm925t Files specific to ARM 925 CPUs
154 /arm926ejs Files specific to ARM 926 CPUs
155 /arm1136 Files specific to ARM 1136 CPUs
156 /ixp Files specific to Intel XScale IXP CPUs
157 /pxa Files specific to Intel XScale PXA CPUs
158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
160 /lib Architecture specific library files
161 /avr32 Files generic to AVR32 architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /blackfin Files generic to Analog Devices Blackfin architecture
165 /cpu CPU specific files
166 /lib Architecture specific library files
167 /x86 Files generic to x86 architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /m68k Files generic to m68k architecture
171 /cpu CPU specific files
172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
177 /lib Architecture specific library files
178 /microblaze Files generic to microblaze architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /mips Files generic to MIPS architecture
182 /cpu CPU specific files
183 /lib Architecture specific library files
184 /nios2 Files generic to Altera NIOS2 architecture
185 /cpu CPU specific files
186 /lib Architecture specific library files
187 /powerpc Files generic to PowerPC architecture
188 /cpu CPU specific files
189 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
190 /mpc5xx Files specific to Freescale MPC5xx CPUs
191 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
192 /mpc8xx Files specific to Freescale MPC8xx CPUs
193 /mpc8220 Files specific to Freescale MPC8220 CPUs
194 /mpc824x Files specific to Freescale MPC824x CPUs
195 /mpc8260 Files specific to Freescale MPC8260 CPUs
196 /mpc85xx Files specific to Freescale MPC85xx CPUs
197 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
198 /lib Architecture specific library files
199 /sh Files generic to SH architecture
200 /cpu CPU specific files
201 /sh2 Files specific to sh2 CPUs
202 /sh3 Files specific to sh3 CPUs
203 /sh4 Files specific to sh4 CPUs
204 /lib Architecture specific library files
205 /sparc Files generic to SPARC architecture
206 /cpu CPU specific files
207 /leon2 Files specific to Gaisler LEON2 SPARC CPU
208 /leon3 Files specific to Gaisler LEON3 SPARC CPU
209 /lib Architecture specific library files
210 /api Machine/arch independent API for external apps
211 /board Board dependent files
212 /common Misc architecture independent functions
213 /disk Code for disk drive partition handling
214 /doc Documentation (don't expect too much)
215 /drivers Commonly used device drivers
216 /examples Example code for standalone applications, etc.
217 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
218 /include Header Files
219 /lib Files generic to all architectures
220 /libfdt Library files to support flattened device trees
221 /lzma Library files to support LZMA decompression
222 /lzo Library files to support LZO decompression
224 /post Power On Self Test
225 /rtc Real Time Clock drivers
226 /tools Tools to build S-Record or U-Boot images, etc.
228 Software Configuration:
229 =======================
231 Configuration is usually done using C preprocessor defines; the
232 rationale behind that is to avoid dead code whenever possible.
234 There are two classes of configuration variables:
236 * Configuration _OPTIONS_:
237 These are selectable by the user and have names beginning with
240 * Configuration _SETTINGS_:
241 These depend on the hardware etc. and should not be meddled with if
242 you don't know what you're doing; they have names beginning with
245 Later we will add a configuration tool - probably similar to or even
246 identical to what's used for the Linux kernel. Right now, we have to
247 do the configuration by hand, which means creating some symbolic
248 links and editing some configuration files. We use the TQM8xxL boards
252 Selection of Processor Architecture and Board Type:
253 ---------------------------------------------------
255 For all supported boards there are ready-to-use default
256 configurations available; just type "make <board_name>_config".
258 Example: For a TQM823L module type:
263 For the Cogent platform, you need to specify the CPU type as well;
264 e.g. "make cogent_mpc8xx_config". And also configure the cogent
265 directory according to the instructions in cogent/README.
268 Configuration Options:
269 ----------------------
271 Configuration depends on the combination of board and CPU type; all
272 such information is kept in a configuration file
273 "include/configs/<board_name>.h".
275 Example: For a TQM823L module, all configuration settings are in
276 "include/configs/TQM823L.h".
279 Many of the options are named exactly as the corresponding Linux
280 kernel configuration options. The intention is to make it easier to
281 build a config tool - later.
284 The following options need to be configured:
286 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
288 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
290 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
291 Define exactly one, e.g. CONFIG_ATSTK1002
293 - CPU Module Type: (if CONFIG_COGENT is defined)
294 Define exactly one of
296 --- FIXME --- not tested yet:
297 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
298 CONFIG_CMA287_23, CONFIG_CMA287_50
300 - Motherboard Type: (if CONFIG_COGENT is defined)
301 Define exactly one of
302 CONFIG_CMA101, CONFIG_CMA102
304 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
305 Define one or more of
308 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
309 Define one or more of
310 CONFIG_LCD_HEARTBEAT - update a character position on
311 the LCD display every second with
314 - Board flavour: (if CONFIG_MPC8260ADS is defined)
317 CONFIG_SYS_8260ADS - original MPC8260ADS
318 CONFIG_SYS_8266ADS - MPC8266ADS
319 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
320 CONFIG_SYS_8272ADS - MPC8272ADS
322 - Marvell Family Member
323 CONFIG_SYS_MVFS - define it if you want to enable
324 multiple fs option at one time
325 for marvell soc family
327 - MPC824X Family Member (if CONFIG_MPC824X is defined)
328 Define exactly one of
329 CONFIG_MPC8240, CONFIG_MPC8245
331 - 8xx CPU Options: (if using an MPC8xx CPU)
332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
333 get_gclk_freq() cannot work
334 e.g. if there is no 32KHz
335 reference PIT/RTC clock
336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
339 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
340 CONFIG_SYS_8xx_CPUCLK_MIN
341 CONFIG_SYS_8xx_CPUCLK_MAX
342 CONFIG_8xx_CPUCLK_DEFAULT
343 See doc/README.MPC866
345 CONFIG_SYS_MEASURE_CPUCLK
347 Define this to measure the actual CPU clock instead
348 of relying on the correctness of the configured
349 values. Mostly useful for board bringup to make sure
350 the PLL is locked at the intended frequency. Note
351 that this requires a (stable) reference clock (32 kHz
352 RTC clock or CONFIG_SYS_8XX_XIN)
354 CONFIG_SYS_DELAYED_ICACHE
356 Define this option if you want to enable the
357 ICache only when Code runs from RAM.
359 - Intel Monahans options:
360 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
362 Defines the Monahans run mode to oscillator
363 ratio. Valid values are 8, 16, 24, 31. The core
364 frequency is this value multiplied by 13 MHz.
366 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
368 Defines the Monahans turbo mode to oscillator
369 ratio. Valid values are 1 (default if undefined) and
370 2. The core frequency as calculated above is multiplied
373 - Linux Kernel Interface:
376 U-Boot stores all clock information in Hz
377 internally. For binary compatibility with older Linux
378 kernels (which expect the clocks passed in the
379 bd_info data to be in MHz) the environment variable
380 "clocks_in_mhz" can be defined so that U-Boot
381 converts clock data to MHZ before passing it to the
383 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
384 "clocks_in_mhz=1" is automatically included in the
387 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
389 When transferring memsize parameter to linux, some versions
390 expect it to be in bytes, others in MB.
391 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
395 New kernel versions are expecting firmware settings to be
396 passed using flattened device trees (based on open firmware
400 * New libfdt-based support
401 * Adds the "fdt" command
402 * The bootm command automatically updates the fdt
404 OF_CPU - The proper name of the cpus node (only required for
405 MPC512X and MPC5xxx based boards).
406 OF_SOC - The proper name of the soc node (only required for
407 MPC512X and MPC5xxx based boards).
408 OF_TBCLK - The timebase frequency.
409 OF_STDOUT_PATH - The path to the console device
411 boards with QUICC Engines require OF_QE to set UCC MAC
414 CONFIG_OF_BOARD_SETUP
416 Board code has addition modification that it wants to make
417 to the flat device tree before handing it off to the kernel
421 This define fills in the correct boot CPU in the boot
422 param header, the default value is zero if undefined.
426 U-Boot can detect if an IDE device is present or not.
427 If not, and this new config option is activated, U-Boot
428 removes the ATA node from the DTS before booting Linux,
429 so the Linux IDE driver does not probe the device and
430 crash. This is needed for buggy hardware (uc101) where
431 no pull down resistor is connected to the signal IDE5V_DD7.
433 - vxWorks boot parameters:
435 bootvx constructs a valid bootline using the following
436 environments variables: bootfile, ipaddr, serverip, hostname.
437 It loads the vxWorks image pointed bootfile.
439 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
440 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
441 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
442 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
444 CONFIG_SYS_VXWORKS_ADD_PARAMS
446 Add it at the end of the bootline. E.g "u=username pw=secret"
448 Note: If a "bootargs" environment is defined, it will overwride
449 the defaults discussed just above.
454 Define this if you want support for Amba PrimeCell PL010 UARTs.
458 Define this if you want support for Amba PrimeCell PL011 UARTs.
462 If you have Amba PrimeCell PL011 UARTs, set this variable to
463 the clock speed of the UARTs.
467 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
468 define this to a list of base addresses for each (supported)
469 port. See e.g. include/configs/versatile.h
473 Depending on board, define exactly one serial port
474 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
475 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
476 console by defining CONFIG_8xx_CONS_NONE
478 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
479 port routines must be defined elsewhere
480 (i.e. serial_init(), serial_getc(), ...)
483 Enables console device for a color framebuffer. Needs following
484 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
485 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
487 VIDEO_HW_RECTFILL graphic chip supports
490 VIDEO_HW_BITBLT graphic chip supports
491 bit-blit (cf. smiLynxEM)
492 VIDEO_VISIBLE_COLS visible pixel columns
494 VIDEO_VISIBLE_ROWS visible pixel rows
495 VIDEO_PIXEL_SIZE bytes per pixel
496 VIDEO_DATA_FORMAT graphic data format
497 (0-5, cf. cfb_console.c)
498 VIDEO_FB_ADRS framebuffer address
499 VIDEO_KBD_INIT_FCT keyboard int fct
500 (i.e. i8042_kbd_init())
501 VIDEO_TSTC_FCT test char fct
503 VIDEO_GETC_FCT get char fct
505 CONFIG_CONSOLE_CURSOR cursor drawing on/off
506 (requires blink timer
508 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
509 CONFIG_CONSOLE_TIME display time/date info in
511 (requires CONFIG_CMD_DATE)
512 CONFIG_VIDEO_LOGO display Linux logo in
514 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
515 linux_logo.h for logo.
516 Requires CONFIG_VIDEO_LOGO
517 CONFIG_CONSOLE_EXTRA_INFO
518 additional board info beside
521 When CONFIG_CFB_CONSOLE is defined, video console is
522 default i/o. Serial console can be forced with
523 environment 'console=serial'.
525 When CONFIG_SILENT_CONSOLE is defined, all console
526 messages (by U-Boot and Linux!) can be silenced with
527 the "silent" environment variable. See
528 doc/README.silent for more information.
531 CONFIG_BAUDRATE - in bps
532 Select one of the baudrates listed in
533 CONFIG_SYS_BAUDRATE_TABLE, see below.
534 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
536 - Console Rx buffer length
537 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
538 the maximum receive buffer length for the SMC.
539 This option is actual only for 82xx and 8xx possible.
540 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
541 must be defined, to setup the maximum idle timeout for
544 - Boot Delay: CONFIG_BOOTDELAY - in seconds
545 Delay before automatically booting the default image;
546 set to -1 to disable autoboot.
548 See doc/README.autoboot for these options that
549 work with CONFIG_BOOTDELAY. None are required.
550 CONFIG_BOOT_RETRY_TIME
551 CONFIG_BOOT_RETRY_MIN
552 CONFIG_AUTOBOOT_KEYED
553 CONFIG_AUTOBOOT_PROMPT
554 CONFIG_AUTOBOOT_DELAY_STR
555 CONFIG_AUTOBOOT_STOP_STR
556 CONFIG_AUTOBOOT_DELAY_STR2
557 CONFIG_AUTOBOOT_STOP_STR2
558 CONFIG_ZERO_BOOTDELAY_CHECK
559 CONFIG_RESET_TO_RETRY
563 Only needed when CONFIG_BOOTDELAY is enabled;
564 define a command string that is automatically executed
565 when no character is read on the console interface
566 within "Boot Delay" after reset.
569 This can be used to pass arguments to the bootm
570 command. The value of CONFIG_BOOTARGS goes into the
571 environment value "bootargs".
573 CONFIG_RAMBOOT and CONFIG_NFSBOOT
574 The value of these goes into the environment as
575 "ramboot" and "nfsboot" respectively, and can be used
576 as a convenience, when switching between booting from
582 When this option is #defined, the existence of the
583 environment variable "preboot" will be checked
584 immediately before starting the CONFIG_BOOTDELAY
585 countdown and/or running the auto-boot command resp.
586 entering interactive mode.
588 This feature is especially useful when "preboot" is
589 automatically generated or modified. For an example
590 see the LWMON board specific code: here "preboot" is
591 modified when the user holds down a certain
592 combination of keys on the (special) keyboard when
595 - Serial Download Echo Mode:
597 If defined to 1, all characters received during a
598 serial download (using the "loads" command) are
599 echoed back. This might be needed by some terminal
600 emulations (like "cu"), but may as well just take
601 time on others. This setting #define's the initial
602 value of the "loads_echo" environment variable.
604 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
606 Select one of the baudrates listed in
607 CONFIG_SYS_BAUDRATE_TABLE, see below.
610 Monitor commands can be included or excluded
611 from the build by using the #include files
612 "config_cmd_all.h" and #undef'ing unwanted
613 commands, or using "config_cmd_default.h"
614 and augmenting with additional #define's
617 The default command configuration includes all commands
618 except those marked below with a "*".
620 CONFIG_CMD_ASKENV * ask for env variable
621 CONFIG_CMD_BDI bdinfo
622 CONFIG_CMD_BEDBUG * Include BedBug Debugger
623 CONFIG_CMD_BMP * BMP support
624 CONFIG_CMD_BSP * Board specific commands
625 CONFIG_CMD_BOOTD bootd
626 CONFIG_CMD_CACHE * icache, dcache
627 CONFIG_CMD_CONSOLE coninfo
628 CONFIG_CMD_CRC32 * crc32
629 CONFIG_CMD_DATE * support for RTC, date/time...
630 CONFIG_CMD_DHCP * DHCP support
631 CONFIG_CMD_DIAG * Diagnostics
632 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
633 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
634 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
635 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
636 CONFIG_CMD_DTT * Digital Therm and Thermostat
637 CONFIG_CMD_ECHO echo arguments
638 CONFIG_CMD_EDITENV edit env variable
639 CONFIG_CMD_EEPROM * EEPROM read/write support
640 CONFIG_CMD_ELF * bootelf, bootvx
641 CONFIG_CMD_EXPORTENV * export the environment
642 CONFIG_CMD_SAVEENV saveenv
643 CONFIG_CMD_FDC * Floppy Disk Support
644 CONFIG_CMD_FAT * FAT partition support
645 CONFIG_CMD_FDOS * Dos diskette Support
646 CONFIG_CMD_FLASH flinfo, erase, protect
647 CONFIG_CMD_FPGA FPGA device initialization support
648 CONFIG_CMD_GO * the 'go' command (exec code)
649 CONFIG_CMD_GREPENV * search environment
650 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
651 CONFIG_CMD_I2C * I2C serial bus support
652 CONFIG_CMD_IDE * IDE harddisk support
653 CONFIG_CMD_IMI iminfo
654 CONFIG_CMD_IMLS List all found images
655 CONFIG_CMD_IMMAP * IMMR dump support
656 CONFIG_CMD_IMPORTENV * import an environment
657 CONFIG_CMD_IRQ * irqinfo
658 CONFIG_CMD_ITEST Integer/string test of 2 values
659 CONFIG_CMD_JFFS2 * JFFS2 Support
660 CONFIG_CMD_KGDB * kgdb
661 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
662 CONFIG_CMD_LOADB loadb
663 CONFIG_CMD_LOADS loads
664 CONFIG_CMD_MD5SUM print md5 message digest
665 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
666 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
668 CONFIG_CMD_MISC Misc functions like sleep etc
669 CONFIG_CMD_MMC * MMC memory mapped support
670 CONFIG_CMD_MII * MII utility commands
671 CONFIG_CMD_MTDPARTS * MTD partition support
672 CONFIG_CMD_NAND * NAND support
673 CONFIG_CMD_NET bootp, tftpboot, rarpboot
674 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
675 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
676 CONFIG_CMD_PCI * pciinfo
677 CONFIG_CMD_PCMCIA * PCMCIA support
678 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
680 CONFIG_CMD_PORTIO * Port I/O
681 CONFIG_CMD_REGINFO * Register dump
682 CONFIG_CMD_RUN run command in env variable
683 CONFIG_CMD_SAVES * save S record dump
684 CONFIG_CMD_SCSI * SCSI Support
685 CONFIG_CMD_SDRAM * print SDRAM configuration information
686 (requires CONFIG_CMD_I2C)
687 CONFIG_CMD_SETGETDCR Support for DCR Register access
689 CONFIG_CMD_SHA1SUM print sha1 memory digest
690 (requires CONFIG_CMD_MEMORY)
691 CONFIG_CMD_SOURCE "source" command Support
692 CONFIG_CMD_SPI * SPI serial bus support
693 CONFIG_CMD_USB * USB support
694 CONFIG_CMD_VFD * VFD support (TRAB)
695 CONFIG_CMD_CDP * Cisco Discover Protocol support
696 CONFIG_CMD_FSL * Microblaze FSL support
699 EXAMPLE: If you want all functions except of network
700 support you can write:
702 #include "config_cmd_all.h"
703 #undef CONFIG_CMD_NET
706 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
708 Note: Don't enable the "icache" and "dcache" commands
709 (configuration option CONFIG_CMD_CACHE) unless you know
710 what you (and your U-Boot users) are doing. Data
711 cache cannot be enabled on systems like the 8xx or
712 8260 (where accesses to the IMMR region must be
713 uncached), and it cannot be disabled on all other
714 systems where we (mis-) use the data cache to hold an
715 initial stack and some data.
718 XXX - this list needs to get updated!
722 If this variable is defined, it enables watchdog
723 support. There must be support in the platform specific
724 code for a watchdog. For the 8xx and 8260 CPUs, the
725 SIU Watchdog feature is enabled in the SYPCR
729 CONFIG_VERSION_VARIABLE
730 If this variable is defined, an environment variable
731 named "ver" is created by U-Boot showing the U-Boot
732 version as printed by the "version" command.
733 This variable is readonly.
737 When CONFIG_CMD_DATE is selected, the type of the RTC
738 has to be selected, too. Define exactly one of the
741 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
742 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
743 CONFIG_RTC_MC13783 - use MC13783 RTC
744 CONFIG_RTC_MC146818 - use MC146818 RTC
745 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
746 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
747 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
748 CONFIG_RTC_DS164x - use Dallas DS164x RTC
749 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
750 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
751 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
752 CONFIG_SYS_RV3029_TCR - enable trickle charger on
755 Note that if the RTC uses I2C, then the I2C interface
756 must also be configured. See I2C Support, below.
759 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
760 CONFIG_PCA953X_INFO - enable pca953x info command
762 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
763 chip-ngpio pairs that tell the PCA953X driver the number of
764 pins supported by a particular chip.
766 Note that if the GPIO device uses I2C, then the I2C interface
767 must also be configured. See I2C Support, below.
771 When CONFIG_TIMESTAMP is selected, the timestamp
772 (date and time) of an image is printed by image
773 commands like bootm or iminfo. This option is
774 automatically enabled when you select CONFIG_CMD_DATE .
777 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
778 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
780 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
781 CONFIG_CMD_SCSI) you must configure support for at
782 least one partition type as well.
785 CONFIG_IDE_RESET_ROUTINE - this is defined in several
786 board configurations files but used nowhere!
788 CONFIG_IDE_RESET - is this is defined, IDE Reset will
789 be performed by calling the function
790 ide_set_reset(int reset)
791 which has to be defined in a board specific file
796 Set this to enable ATAPI support.
801 Set this to enable support for disks larger than 137GB
802 Also look at CONFIG_SYS_64BIT_LBA.
803 Whithout these , LBA48 support uses 32bit variables and will 'only'
804 support disks up to 2.1TB.
806 CONFIG_SYS_64BIT_LBA:
807 When enabled, makes the IDE subsystem use 64bit sector addresses.
811 At the moment only there is only support for the
812 SYM53C8XX SCSI controller; define
813 CONFIG_SCSI_SYM53C8XX to enable it.
815 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
816 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
817 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
818 maximum numbers of LUNs, SCSI ID's and target
820 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
822 - NETWORK Support (PCI):
824 Support for Intel 8254x gigabit chips.
826 CONFIG_E1000_FALLBACK_MAC
827 default MAC for empty EEPROM after production.
830 Support for Intel 82557/82559/82559ER chips.
831 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
832 write routine for first time initialisation.
835 Support for Digital 2114x chips.
836 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
837 modem chip initialisation (KS8761/QS6611).
840 Support for National dp83815 chips.
843 Support for National dp8382[01] gigabit chips.
845 - NETWORK Support (other):
847 CONFIG_DRIVER_AT91EMAC
848 Support for AT91RM9200 EMAC.
851 Define this to use reduced MII inteface
853 CONFIG_DRIVER_AT91EMAC_QUIET
854 If this defined, the driver is quiet.
855 The driver doen't show link status messages.
857 CONFIG_DRIVER_LAN91C96
858 Support for SMSC's LAN91C96 chips.
861 Define this to hold the physical address
862 of the LAN91C96's I/O space
864 CONFIG_LAN91C96_USE_32_BIT
865 Define this to enable 32 bit addressing
867 CONFIG_DRIVER_SMC91111
868 Support for SMSC's LAN91C111 chip
871 Define this to hold the physical address
872 of the device (I/O space)
874 CONFIG_SMC_USE_32_BIT
875 Define this if data bus is 32 bits
877 CONFIG_SMC_USE_IOFUNCS
878 Define this to use i/o functions instead of macros
879 (some hardware wont work with macros)
882 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
884 CONFIG_FTGMAC100_EGIGA
885 Define this to use GE link update with gigabit PHY.
886 Define this if FTGMAC100 is connected to gigabit PHY.
887 If your system has 10/100 PHY only, it might not occur
888 wrong behavior. Because PHY usually return timeout or
889 useless data when polling gigabit status and gigabit
890 control registers. This behavior won't affect the
891 correctnessof 10/100 link speed update.
894 Support for SMSC's LAN911x and LAN921x chips
897 Define this to hold the physical address
898 of the device (I/O space)
900 CONFIG_SMC911X_32_BIT
901 Define this if data bus is 32 bits
903 CONFIG_SMC911X_16_BIT
904 Define this if data bus is 16 bits. If your processor
905 automatically converts one 32 bit word to two 16 bit
906 words you may also try CONFIG_SMC911X_32_BIT.
909 Support for Renesas on-chip Ethernet controller
911 CONFIG_SH_ETHER_USE_PORT
912 Define the number of ports to be used
914 CONFIG_SH_ETHER_PHY_ADDR
915 Define the ETH PHY's address
917 CONFIG_SH_ETHER_CACHE_WRITEBACK
918 If this option is set, the driver enables cache flush.
921 At the moment only the UHCI host controller is
922 supported (PIP405, MIP405, MPC5200); define
923 CONFIG_USB_UHCI to enable it.
924 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
925 and define CONFIG_USB_STORAGE to enable the USB
928 Supported are USB Keyboards and USB Floppy drives
930 MPC5200 USB requires additional defines:
932 for 528 MHz Clock: 0x0001bbbb
936 for differential drivers: 0x00001000
937 for single ended drivers: 0x00005000
938 for differential drivers on PSC3: 0x00000100
939 for single ended drivers on PSC3: 0x00004100
940 CONFIG_SYS_USB_EVENT_POLL
941 May be defined to allow interrupt polling
942 instead of using asynchronous interrupts
945 Define the below if you wish to use the USB console.
946 Once firmware is rebuilt from a serial console issue the
947 command "setenv stdin usbtty; setenv stdout usbtty" and
948 attach your USB cable. The Unix command "dmesg" should print
949 it has found a new device. The environment variable usbtty
950 can be set to gserial or cdc_acm to enable your device to
951 appear to a USB host as a Linux gserial device or a
952 Common Device Class Abstract Control Model serial device.
953 If you select usbtty = gserial you should be able to enumerate
955 # modprobe usbserial vendor=0xVendorID product=0xProductID
956 else if using cdc_acm, simply setting the environment
957 variable usbtty to be cdc_acm should suffice. The following
958 might be defined in YourBoardName.h
961 Define this to build a UDC device
964 Define this to have a tty type of device available to
965 talk to the UDC device
967 CONFIG_SYS_CONSOLE_IS_IN_ENV
968 Define this if you want stdin, stdout &/or stderr to
972 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
973 Derive USB clock from external clock "blah"
974 - CONFIG_SYS_USB_EXTC_CLK 0x02
976 CONFIG_SYS_USB_BRG_CLK 0xBLAH
977 Derive USB clock from brgclk
978 - CONFIG_SYS_USB_BRG_CLK 0x04
980 If you have a USB-IF assigned VendorID then you may wish to
981 define your own vendor specific values either in BoardName.h
982 or directly in usbd_vendor_info.h. If you don't define
983 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
984 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
985 should pretend to be a Linux device to it's target host.
987 CONFIG_USBD_MANUFACTURER
988 Define this string as the name of your company for
989 - CONFIG_USBD_MANUFACTURER "my company"
991 CONFIG_USBD_PRODUCT_NAME
992 Define this string as the name of your product
993 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
996 Define this as your assigned Vendor ID from the USB
997 Implementors Forum. This *must* be a genuine Vendor ID
998 to avoid polluting the USB namespace.
999 - CONFIG_USBD_VENDORID 0xFFFF
1001 CONFIG_USBD_PRODUCTID
1002 Define this as the unique Product ID
1004 - CONFIG_USBD_PRODUCTID 0xFFFF
1008 The MMC controller on the Intel PXA is supported. To
1009 enable this define CONFIG_MMC. The MMC can be
1010 accessed from the boot prompt by mapping the device
1011 to physical memory similar to flash. Command line is
1012 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1013 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1015 - Journaling Flash filesystem support:
1016 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1017 CONFIG_JFFS2_NAND_DEV
1018 Define these for a default partition on a NAND device
1020 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1021 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1022 Define these for a default partition on a NOR device
1024 CONFIG_SYS_JFFS_CUSTOM_PART
1025 Define this to create an own partition. You have to provide a
1026 function struct part_info* jffs2_part_info(int part_num)
1028 If you define only one JFFS2 partition you may also want to
1029 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1030 to disable the command chpart. This is the default when you
1031 have not defined a custom partition
1036 Define this to enable standard (PC-Style) keyboard
1040 Standard PC keyboard driver with US (is default) and
1041 GERMAN key layout (switch via environment 'keymap=de') support.
1042 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1043 for cfb_console. Supports cursor blinking.
1048 Define this to enable video support (for output to
1051 CONFIG_VIDEO_CT69000
1053 Enable Chips & Technologies 69000 Video chip
1055 CONFIG_VIDEO_SMI_LYNXEM
1056 Enable Silicon Motion SMI 712/710/810 Video chip. The
1057 video output is selected via environment 'videoout'
1058 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1061 For the CT69000 and SMI_LYNXEM drivers, videomode is
1062 selected via environment 'videomode'. Two different ways
1064 - "videomode=num" 'num' is a standard LiLo mode numbers.
1065 Following standard modes are supported (* is default):
1067 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1068 -------------+---------------------------------------------
1069 8 bits | 0x301* 0x303 0x305 0x161 0x307
1070 15 bits | 0x310 0x313 0x316 0x162 0x319
1071 16 bits | 0x311 0x314 0x317 0x163 0x31A
1072 24 bits | 0x312 0x315 0x318 ? 0x31B
1073 -------------+---------------------------------------------
1074 (i.e. setenv videomode 317; saveenv; reset;)
1076 - "videomode=bootargs" all the video parameters are parsed
1077 from the bootargs. (See drivers/video/videomodes.c)
1080 CONFIG_VIDEO_SED13806
1081 Enable Epson SED13806 driver. This driver supports 8bpp
1082 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1083 or CONFIG_VIDEO_SED13806_16BPP
1086 Enable the Freescale DIU video driver. Reference boards for
1087 SOCs that have a DIU should define this macro to enable DIU
1088 support, and should also define these other macros:
1094 CONFIG_VIDEO_SW_CURSOR
1095 CONFIG_VGA_AS_SINGLE_DEVICE
1097 CONFIG_VIDEO_BMP_LOGO
1099 The DIU driver will look for the 'monitor' environment variable,
1100 and if defined, enable the DIU as a console during boot. This
1101 variable should be set to one of these values:
1103 '0' Output video to the DVI connector
1104 '1' Output video to the LVDS connector
1105 '2' Output video to the Dual-Link LVDS connector
1110 Define this to enable a custom keyboard support.
1111 This simply calls drv_keyboard_init() which must be
1112 defined in your board-specific files.
1113 The only board using this so far is RBC823.
1115 - LCD Support: CONFIG_LCD
1117 Define this to enable LCD support (for output to LCD
1118 display); also select one of the supported displays
1119 by defining one of these:
1123 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1125 CONFIG_NEC_NL6448AC33:
1127 NEC NL6448AC33-18. Active, color, single scan.
1129 CONFIG_NEC_NL6448BC20
1131 NEC NL6448BC20-08. 6.5", 640x480.
1132 Active, color, single scan.
1134 CONFIG_NEC_NL6448BC33_54
1136 NEC NL6448BC33-54. 10.4", 640x480.
1137 Active, color, single scan.
1141 Sharp 320x240. Active, color, single scan.
1142 It isn't 16x9, and I am not sure what it is.
1144 CONFIG_SHARP_LQ64D341
1146 Sharp LQ64D341 display, 640x480.
1147 Active, color, single scan.
1151 HLD1045 display, 640x480.
1152 Active, color, single scan.
1156 Optrex CBL50840-2 NF-FW 99 22 M5
1158 Hitachi LMG6912RPFC-00T
1162 320x240. Black & white.
1164 Normally display is black on white background; define
1165 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1167 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1169 If this option is set, the environment is checked for
1170 a variable "splashimage". If found, the usual display
1171 of logo, copyright and system information on the LCD
1172 is suppressed and the BMP image at the address
1173 specified in "splashimage" is loaded instead. The
1174 console is redirected to the "nulldev", too. This
1175 allows for a "silent" boot where a splash screen is
1176 loaded very quickly after power-on.
1178 CONFIG_SPLASH_SCREEN_ALIGN
1180 If this option is set the splash image can be freely positioned
1181 on the screen. Environment variable "splashpos" specifies the
1182 position as "x,y". If a positive number is given it is used as
1183 number of pixel from left/top. If a negative number is given it
1184 is used as number of pixel from right/bottom. You can also
1185 specify 'm' for centering the image.
1188 setenv splashpos m,m
1189 => image at center of screen
1191 setenv splashpos 30,20
1192 => image at x = 30 and y = 20
1194 setenv splashpos -10,m
1195 => vertically centered image
1196 at x = dspWidth - bmpWidth - 9
1198 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1200 If this option is set, additionally to standard BMP
1201 images, gzipped BMP images can be displayed via the
1202 splashscreen support or the bmp command.
1204 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1206 If this option is set, 8-bit RLE compressed BMP images
1207 can be displayed via the splashscreen support or the
1210 - Compression support:
1213 If this option is set, support for bzip2 compressed
1214 images is included. If not, only uncompressed and gzip
1215 compressed images are supported.
1217 NOTE: the bzip2 algorithm requires a lot of RAM, so
1218 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1223 If this option is set, support for lzma compressed
1226 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1227 requires an amount of dynamic memory that is given by the
1230 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1232 Where lc and lp stand for, respectively, Literal context bits
1233 and Literal pos bits.
1235 This value is upper-bounded by 14MB in the worst case. Anyway,
1236 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1237 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1238 a very small buffer.
1240 Use the lzmainfo tool to determinate the lc and lp values and
1241 then calculate the amount of needed dynamic memory (ensuring
1242 the appropriate CONFIG_SYS_MALLOC_LEN value).
1247 The address of PHY on MII bus.
1249 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1251 The clock frequency of the MII bus
1255 If this option is set, support for speed/duplex
1256 detection of gigabit PHY is included.
1258 CONFIG_PHY_RESET_DELAY
1260 Some PHY like Intel LXT971A need extra delay after
1261 reset before any MII register access is possible.
1262 For such PHY, set this option to the usec delay
1263 required. (minimum 300usec for LXT971A)
1265 CONFIG_PHY_CMD_DELAY (ppc4xx)
1267 Some PHY like Intel LXT971A need extra delay after
1268 command issued before MII status register can be read
1278 Define a default value for Ethernet address to use
1279 for the respective Ethernet interface, in case this
1280 is not determined automatically.
1285 Define a default value for the IP address to use for
1286 the default Ethernet interface, in case this is not
1287 determined through e.g. bootp.
1289 - Server IP address:
1292 Defines a default value for the IP address of a TFTP
1293 server to contact when using the "tftboot" command.
1295 CONFIG_KEEP_SERVERADDR
1297 Keeps the server's MAC address, in the env 'serveraddr'
1298 for passing to bootargs (like Linux's netconsole option)
1300 - Multicast TFTP Mode:
1303 Defines whether you want to support multicast TFTP as per
1304 rfc-2090; for example to work with atftp. Lets lots of targets
1305 tftp down the same boot image concurrently. Note: the Ethernet
1306 driver in use must provide a function: mcast() to join/leave a
1309 CONFIG_BOOTP_RANDOM_DELAY
1310 - BOOTP Recovery Mode:
1311 CONFIG_BOOTP_RANDOM_DELAY
1313 If you have many targets in a network that try to
1314 boot using BOOTP, you may want to avoid that all
1315 systems send out BOOTP requests at precisely the same
1316 moment (which would happen for instance at recovery
1317 from a power failure, when all systems will try to
1318 boot, thus flooding the BOOTP server. Defining
1319 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1320 inserted before sending out BOOTP requests. The
1321 following delays are inserted then:
1323 1st BOOTP request: delay 0 ... 1 sec
1324 2nd BOOTP request: delay 0 ... 2 sec
1325 3rd BOOTP request: delay 0 ... 4 sec
1327 BOOTP requests: delay 0 ... 8 sec
1329 - DHCP Advanced Options:
1330 You can fine tune the DHCP functionality by defining
1331 CONFIG_BOOTP_* symbols:
1333 CONFIG_BOOTP_SUBNETMASK
1334 CONFIG_BOOTP_GATEWAY
1335 CONFIG_BOOTP_HOSTNAME
1336 CONFIG_BOOTP_NISDOMAIN
1337 CONFIG_BOOTP_BOOTPATH
1338 CONFIG_BOOTP_BOOTFILESIZE
1341 CONFIG_BOOTP_SEND_HOSTNAME
1342 CONFIG_BOOTP_NTPSERVER
1343 CONFIG_BOOTP_TIMEOFFSET
1344 CONFIG_BOOTP_VENDOREX
1346 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1347 environment variable, not the BOOTP server.
1349 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1350 serverip from a DHCP server, it is possible that more
1351 than one DNS serverip is offered to the client.
1352 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1353 serverip will be stored in the additional environment
1354 variable "dnsip2". The first DNS serverip is always
1355 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1358 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1359 to do a dynamic update of a DNS server. To do this, they
1360 need the hostname of the DHCP requester.
1361 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1362 of the "hostname" environment variable is passed as
1363 option 12 to the DHCP server.
1365 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1367 A 32bit value in microseconds for a delay between
1368 receiving a "DHCP Offer" and sending the "DHCP Request".
1369 This fixes a problem with certain DHCP servers that don't
1370 respond 100% of the time to a "DHCP request". E.g. On an
1371 AT91RM9200 processor running at 180MHz, this delay needed
1372 to be *at least* 15,000 usec before a Windows Server 2003
1373 DHCP server would reply 100% of the time. I recommend at
1374 least 50,000 usec to be safe. The alternative is to hope
1375 that one of the retries will be successful but note that
1376 the DHCP timeout and retry process takes a longer than
1380 CONFIG_CDP_DEVICE_ID
1382 The device id used in CDP trigger frames.
1384 CONFIG_CDP_DEVICE_ID_PREFIX
1386 A two character string which is prefixed to the MAC address
1391 A printf format string which contains the ascii name of
1392 the port. Normally is set to "eth%d" which sets
1393 eth0 for the first Ethernet, eth1 for the second etc.
1395 CONFIG_CDP_CAPABILITIES
1397 A 32bit integer which indicates the device capabilities;
1398 0x00000010 for a normal host which does not forwards.
1402 An ascii string containing the version of the software.
1406 An ascii string containing the name of the platform.
1410 A 32bit integer sent on the trigger.
1412 CONFIG_CDP_POWER_CONSUMPTION
1414 A 16bit integer containing the power consumption of the
1415 device in .1 of milliwatts.
1417 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1419 A byte containing the id of the VLAN.
1421 - Status LED: CONFIG_STATUS_LED
1423 Several configurations allow to display the current
1424 status using a LED. For instance, the LED will blink
1425 fast while running U-Boot code, stop blinking as
1426 soon as a reply to a BOOTP request was received, and
1427 start blinking slow once the Linux kernel is running
1428 (supported by a status LED driver in the Linux
1429 kernel). Defining CONFIG_STATUS_LED enables this
1432 - CAN Support: CONFIG_CAN_DRIVER
1434 Defining CONFIG_CAN_DRIVER enables CAN driver support
1435 on those systems that support this (optional)
1436 feature, like the TQM8xxL modules.
1438 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1440 These enable I2C serial bus commands. Defining either of
1441 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1442 include the appropriate I2C driver for the selected CPU.
1444 This will allow you to use i2c commands at the u-boot
1445 command line (as long as you set CONFIG_CMD_I2C in
1446 CONFIG_COMMANDS) and communicate with i2c based realtime
1447 clock chips. See common/cmd_i2c.c for a description of the
1448 command line interface.
1450 CONFIG_HARD_I2C selects a hardware I2C controller.
1452 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1453 bit-banging) driver instead of CPM or similar hardware
1456 There are several other quantities that must also be
1457 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1459 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1460 to be the frequency (in Hz) at which you wish your i2c bus
1461 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1462 the CPU's i2c node address).
1464 Now, the u-boot i2c code for the mpc8xx
1465 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1466 and so its address should therefore be cleared to 0 (See,
1467 eg, MPC823e User's Manual p.16-473). So, set
1468 CONFIG_SYS_I2C_SLAVE to 0.
1470 CONFIG_SYS_I2C_INIT_MPC5XXX
1472 When a board is reset during an i2c bus transfer
1473 chips might think that the current transfer is still
1474 in progress. Reset the slave devices by sending start
1475 commands until the slave device responds.
1477 That's all that's required for CONFIG_HARD_I2C.
1479 If you use the software i2c interface (CONFIG_SOFT_I2C)
1480 then the following macros need to be defined (examples are
1481 from include/configs/lwmon.h):
1485 (Optional). Any commands necessary to enable the I2C
1486 controller or configure ports.
1488 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1492 (Only for MPC8260 CPU). The I/O port to use (the code
1493 assumes both bits are on the same port). Valid values
1494 are 0..3 for ports A..D.
1498 The code necessary to make the I2C data line active
1499 (driven). If the data line is open collector, this
1502 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1506 The code necessary to make the I2C data line tri-stated
1507 (inactive). If the data line is open collector, this
1510 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1514 Code that returns TRUE if the I2C data line is high,
1517 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1521 If <bit> is TRUE, sets the I2C data line high. If it
1522 is FALSE, it clears it (low).
1524 eg: #define I2C_SDA(bit) \
1525 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1526 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1530 If <bit> is TRUE, sets the I2C clock line high. If it
1531 is FALSE, it clears it (low).
1533 eg: #define I2C_SCL(bit) \
1534 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1535 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1539 This delay is invoked four times per clock cycle so this
1540 controls the rate of data transfer. The data rate thus
1541 is 1 / (I2C_DELAY * 4). Often defined to be something
1544 #define I2C_DELAY udelay(2)
1546 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1548 If your arch supports the generic GPIO framework (asm/gpio.h),
1549 then you may alternatively define the two GPIOs that are to be
1550 used as SCL / SDA. Any of the previous I2C_xxx macros will
1551 have GPIO-based defaults assigned to them as appropriate.
1553 You should define these to the GPIO value as given directly to
1554 the generic GPIO functions.
1556 CONFIG_SYS_I2C_INIT_BOARD
1558 When a board is reset during an i2c bus transfer
1559 chips might think that the current transfer is still
1560 in progress. On some boards it is possible to access
1561 the i2c SCLK line directly, either by using the
1562 processor pin as a GPIO or by having a second pin
1563 connected to the bus. If this option is defined a
1564 custom i2c_init_board() routine in boards/xxx/board.c
1565 is run early in the boot sequence.
1567 CONFIG_SYS_I2C_BOARD_LATE_INIT
1569 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1570 defined a custom i2c_board_late_init() routine in
1571 boards/xxx/board.c is run AFTER the operations in i2c_init()
1572 is completed. This callpoint can be used to unreset i2c bus
1573 using CPU i2c controller register accesses for CPUs whose i2c
1574 controller provide such a method. It is called at the end of
1575 i2c_init() to allow i2c_init operations to setup the i2c bus
1576 controller on the CPU (e.g. setting bus speed & slave address).
1578 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1580 This option enables configuration of bi_iic_fast[] flags
1581 in u-boot bd_info structure based on u-boot environment
1582 variable "i2cfast". (see also i2cfast)
1584 CONFIG_I2C_MULTI_BUS
1586 This option allows the use of multiple I2C buses, each of which
1587 must have a controller. At any point in time, only one bus is
1588 active. To switch to a different bus, use the 'i2c dev' command.
1589 Note that bus numbering is zero-based.
1591 CONFIG_SYS_I2C_NOPROBES
1593 This option specifies a list of I2C devices that will be skipped
1594 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1595 is set, specify a list of bus-device pairs. Otherwise, specify
1596 a 1D array of device addresses
1599 #undef CONFIG_I2C_MULTI_BUS
1600 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1602 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1604 #define CONFIG_I2C_MULTI_BUS
1605 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1607 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1609 CONFIG_SYS_SPD_BUS_NUM
1611 If defined, then this indicates the I2C bus number for DDR SPD.
1612 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1614 CONFIG_SYS_RTC_BUS_NUM
1616 If defined, then this indicates the I2C bus number for the RTC.
1617 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1619 CONFIG_SYS_DTT_BUS_NUM
1621 If defined, then this indicates the I2C bus number for the DTT.
1622 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1624 CONFIG_SYS_I2C_DTT_ADDR:
1626 If defined, specifies the I2C address of the DTT device.
1627 If not defined, then U-Boot uses predefined value for
1628 specified DTT device.
1632 Define this option if you want to use Freescale's I2C driver in
1633 drivers/i2c/fsl_i2c.c.
1637 Define this option if you have I2C devices reached over 1 .. n
1638 I2C Muxes like the pca9544a. This option addes a new I2C
1639 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1640 new I2C Bus to the existing I2C Busses. If you select the
1641 new Bus with "i2c dev", u-bbot sends first the commandos for
1642 the muxes to activate this new "bus".
1644 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1648 Adding a new I2C Bus reached over 2 pca9544a muxes
1649 The First mux with address 70 and channel 6
1650 The Second mux with address 71 and channel 4
1652 => i2c bus pca9544a:70:6:pca9544a:71:4
1654 Use the "i2c bus" command without parameter, to get a list
1655 of I2C Busses with muxes:
1658 Busses reached over muxes:
1660 reached over Mux(es):
1663 reached over Mux(es):
1668 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1669 u-boot sends First the Commando to the mux@70 to enable
1670 channel 6, and then the Commando to the mux@71 to enable
1673 After that, you can use the "normal" i2c commands as
1674 usual, to communicate with your I2C devices behind
1677 This option is actually implemented for the bitbanging
1678 algorithm in common/soft_i2c.c and for the Hardware I2C
1679 Bus on the MPC8260. But it should be not so difficult
1680 to add this option to other architectures.
1682 CONFIG_SOFT_I2C_READ_REPEATED_START
1684 defining this will force the i2c_read() function in
1685 the soft_i2c driver to perform an I2C repeated start
1686 between writing the address pointer and reading the
1687 data. If this define is omitted the default behaviour
1688 of doing a stop-start sequence will be used. Most I2C
1689 devices can use either method, but some require one or
1692 - SPI Support: CONFIG_SPI
1694 Enables SPI driver (so far only tested with
1695 SPI EEPROM, also an instance works with Crystal A/D and
1696 D/As on the SACSng board)
1700 Enables the driver for SPI controller on SuperH. Currently
1701 only SH7757 is supported.
1705 Enables extended (16-bit) SPI EEPROM addressing.
1706 (symmetrical to CONFIG_I2C_X)
1710 Enables a software (bit-bang) SPI driver rather than
1711 using hardware support. This is a general purpose
1712 driver that only requires three general I/O port pins
1713 (two outputs, one input) to function. If this is
1714 defined, the board configuration must define several
1715 SPI configuration items (port pins to use, etc). For
1716 an example, see include/configs/sacsng.h.
1720 Enables a hardware SPI driver for general-purpose reads
1721 and writes. As with CONFIG_SOFT_SPI, the board configuration
1722 must define a list of chip-select function pointers.
1723 Currently supported on some MPC8xxx processors. For an
1724 example, see include/configs/mpc8349emds.h.
1728 Enables the driver for the SPI controllers on i.MX and MXC
1729 SoCs. Currently only i.MX31 is supported.
1731 - FPGA Support: CONFIG_FPGA
1733 Enables FPGA subsystem.
1735 CONFIG_FPGA_<vendor>
1737 Enables support for specific chip vendors.
1740 CONFIG_FPGA_<family>
1742 Enables support for FPGA family.
1743 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1747 Specify the number of FPGA devices to support.
1749 CONFIG_SYS_FPGA_PROG_FEEDBACK
1751 Enable printing of hash marks during FPGA configuration.
1753 CONFIG_SYS_FPGA_CHECK_BUSY
1755 Enable checks on FPGA configuration interface busy
1756 status by the configuration function. This option
1757 will require a board or device specific function to
1762 If defined, a function that provides delays in the FPGA
1763 configuration driver.
1765 CONFIG_SYS_FPGA_CHECK_CTRLC
1766 Allow Control-C to interrupt FPGA configuration
1768 CONFIG_SYS_FPGA_CHECK_ERROR
1770 Check for configuration errors during FPGA bitfile
1771 loading. For example, abort during Virtex II
1772 configuration if the INIT_B line goes low (which
1773 indicated a CRC error).
1775 CONFIG_SYS_FPGA_WAIT_INIT
1777 Maximum time to wait for the INIT_B line to deassert
1778 after PROB_B has been deasserted during a Virtex II
1779 FPGA configuration sequence. The default time is 500
1782 CONFIG_SYS_FPGA_WAIT_BUSY
1784 Maximum time to wait for BUSY to deassert during
1785 Virtex II FPGA configuration. The default is 5 ms.
1787 CONFIG_SYS_FPGA_WAIT_CONFIG
1789 Time to wait after FPGA configuration. The default is
1792 - Configuration Management:
1795 If defined, this string will be added to the U-Boot
1796 version information (U_BOOT_VERSION)
1798 - Vendor Parameter Protection:
1800 U-Boot considers the values of the environment
1801 variables "serial#" (Board Serial Number) and
1802 "ethaddr" (Ethernet Address) to be parameters that
1803 are set once by the board vendor / manufacturer, and
1804 protects these variables from casual modification by
1805 the user. Once set, these variables are read-only,
1806 and write or delete attempts are rejected. You can
1807 change this behaviour:
1809 If CONFIG_ENV_OVERWRITE is #defined in your config
1810 file, the write protection for vendor parameters is
1811 completely disabled. Anybody can change or delete
1814 Alternatively, if you #define _both_ CONFIG_ETHADDR
1815 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1816 Ethernet address is installed in the environment,
1817 which can be changed exactly ONCE by the user. [The
1818 serial# is unaffected by this, i. e. it remains
1824 Define this variable to enable the reservation of
1825 "protected RAM", i. e. RAM which is not overwritten
1826 by U-Boot. Define CONFIG_PRAM to hold the number of
1827 kB you want to reserve for pRAM. You can overwrite
1828 this default value by defining an environment
1829 variable "pram" to the number of kB you want to
1830 reserve. Note that the board info structure will
1831 still show the full amount of RAM. If pRAM is
1832 reserved, a new environment variable "mem" will
1833 automatically be defined to hold the amount of
1834 remaining RAM in a form that can be passed as boot
1835 argument to Linux, for instance like that:
1837 setenv bootargs ... mem=\${mem}
1840 This way you can tell Linux not to use this memory,
1841 either, which results in a memory region that will
1842 not be affected by reboots.
1844 *WARNING* If your board configuration uses automatic
1845 detection of the RAM size, you must make sure that
1846 this memory test is non-destructive. So far, the
1847 following board configurations are known to be
1850 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1851 HERMES, IP860, RPXlite, LWMON, LANTEC,
1857 Define this variable to stop the system in case of a
1858 fatal error, so that you have to reset it manually.
1859 This is probably NOT a good idea for an embedded
1860 system where you want the system to reboot
1861 automatically as fast as possible, but it may be
1862 useful during development since you can try to debug
1863 the conditions that lead to the situation.
1865 CONFIG_NET_RETRY_COUNT
1867 This variable defines the number of retries for
1868 network operations like ARP, RARP, TFTP, or BOOTP
1869 before giving up the operation. If not defined, a
1870 default value of 5 is used.
1874 Timeout waiting for an ARP reply in milliseconds.
1876 - Command Interpreter:
1877 CONFIG_AUTO_COMPLETE
1879 Enable auto completion of commands using TAB.
1881 Note that this feature has NOT been implemented yet
1882 for the "hush" shell.
1885 CONFIG_SYS_HUSH_PARSER
1887 Define this variable to enable the "hush" shell (from
1888 Busybox) as command line interpreter, thus enabling
1889 powerful command line syntax like
1890 if...then...else...fi conditionals or `&&' and '||'
1891 constructs ("shell scripts").
1893 If undefined, you get the old, much simpler behaviour
1894 with a somewhat smaller memory footprint.
1897 CONFIG_SYS_PROMPT_HUSH_PS2
1899 This defines the secondary prompt string, which is
1900 printed when the command interpreter needs more input
1901 to complete a command. Usually "> ".
1905 In the current implementation, the local variables
1906 space and global environment variables space are
1907 separated. Local variables are those you define by
1908 simply typing `name=value'. To access a local
1909 variable later on, you have write `$name' or
1910 `${name}'; to execute the contents of a variable
1911 directly type `$name' at the command prompt.
1913 Global environment variables are those you use
1914 setenv/printenv to work with. To run a command stored
1915 in such a variable, you need to use the run command,
1916 and you must not use the '$' sign to access them.
1918 To store commands and special characters in a
1919 variable, please use double quotation marks
1920 surrounding the whole text of the variable, instead
1921 of the backslashes before semicolons and special
1924 - Commandline Editing and History:
1925 CONFIG_CMDLINE_EDITING
1927 Enable editing and History functions for interactive
1928 commandline input operations
1930 - Default Environment:
1931 CONFIG_EXTRA_ENV_SETTINGS
1933 Define this to contain any number of null terminated
1934 strings (variable = value pairs) that will be part of
1935 the default environment compiled into the boot image.
1937 For example, place something like this in your
1938 board's config file:
1940 #define CONFIG_EXTRA_ENV_SETTINGS \
1944 Warning: This method is based on knowledge about the
1945 internal format how the environment is stored by the
1946 U-Boot code. This is NOT an official, exported
1947 interface! Although it is unlikely that this format
1948 will change soon, there is no guarantee either.
1949 You better know what you are doing here.
1951 Note: overly (ab)use of the default environment is
1952 discouraged. Make sure to check other ways to preset
1953 the environment like the "source" command or the
1956 - DataFlash Support:
1957 CONFIG_HAS_DATAFLASH
1959 Defining this option enables DataFlash features and
1960 allows to read/write in Dataflash via the standard
1963 - SystemACE Support:
1966 Adding this option adds support for Xilinx SystemACE
1967 chips attached via some sort of local bus. The address
1968 of the chip must also be defined in the
1969 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
1971 #define CONFIG_SYSTEMACE
1972 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
1974 When SystemACE support is added, the "ace" device type
1975 becomes available to the fat commands, i.e. fatls.
1977 - TFTP Fixed UDP Port:
1980 If this is defined, the environment variable tftpsrcp
1981 is used to supply the TFTP UDP source port value.
1982 If tftpsrcp isn't defined, the normal pseudo-random port
1983 number generator is used.
1985 Also, the environment variable tftpdstp is used to supply
1986 the TFTP UDP destination port value. If tftpdstp isn't
1987 defined, the normal port 69 is used.
1989 The purpose for tftpsrcp is to allow a TFTP server to
1990 blindly start the TFTP transfer using the pre-configured
1991 target IP address and UDP port. This has the effect of
1992 "punching through" the (Windows XP) firewall, allowing
1993 the remainder of the TFTP transfer to proceed normally.
1994 A better solution is to properly configure the firewall,
1995 but sometimes that is not allowed.
1997 - Show boot progress:
1998 CONFIG_SHOW_BOOT_PROGRESS
2000 Defining this option allows to add some board-
2001 specific code (calling a user-provided function
2002 "show_boot_progress(int)") that enables you to show
2003 the system's boot progress on some display (for
2004 example, some LED's) on your board. At the moment,
2005 the following checkpoints are implemented:
2007 - Standalone program support:
2008 CONFIG_STANDALONE_LOAD_ADDR
2010 This option allows to define board specific values
2011 for the address where standalone program gets loaded,
2012 thus overwriting the architecutre dependent default
2015 - Frame Buffer Address:
2018 Define CONFIG_FB_ADDR if you want to use specific address for
2020 Then system will reserve the frame buffer address to defined address
2021 instead of lcd_setmem (this function grab the memory for frame buffer
2024 Please see board_init_f function.
2026 If you want this config option then,
2027 please define it at your board config file
2029 Legacy uImage format:
2032 1 common/cmd_bootm.c before attempting to boot an image
2033 -1 common/cmd_bootm.c Image header has bad magic number
2034 2 common/cmd_bootm.c Image header has correct magic number
2035 -2 common/cmd_bootm.c Image header has bad checksum
2036 3 common/cmd_bootm.c Image header has correct checksum
2037 -3 common/cmd_bootm.c Image data has bad checksum
2038 4 common/cmd_bootm.c Image data has correct checksum
2039 -4 common/cmd_bootm.c Image is for unsupported architecture
2040 5 common/cmd_bootm.c Architecture check OK
2041 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2042 6 common/cmd_bootm.c Image Type check OK
2043 -6 common/cmd_bootm.c gunzip uncompression error
2044 -7 common/cmd_bootm.c Unimplemented compression type
2045 7 common/cmd_bootm.c Uncompression OK
2046 8 common/cmd_bootm.c No uncompress/copy overwrite error
2047 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2049 9 common/image.c Start initial ramdisk verification
2050 -10 common/image.c Ramdisk header has bad magic number
2051 -11 common/image.c Ramdisk header has bad checksum
2052 10 common/image.c Ramdisk header is OK
2053 -12 common/image.c Ramdisk data has bad checksum
2054 11 common/image.c Ramdisk data has correct checksum
2055 12 common/image.c Ramdisk verification complete, start loading
2056 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2057 13 common/image.c Start multifile image verification
2058 14 common/image.c No initial ramdisk, no multifile, continue.
2060 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2062 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2063 -31 post/post.c POST test failed, detected by post_output_backlog()
2064 -32 post/post.c POST test failed, detected by post_run_single()
2066 34 common/cmd_doc.c before loading a Image from a DOC device
2067 -35 common/cmd_doc.c Bad usage of "doc" command
2068 35 common/cmd_doc.c correct usage of "doc" command
2069 -36 common/cmd_doc.c No boot device
2070 36 common/cmd_doc.c correct boot device
2071 -37 common/cmd_doc.c Unknown Chip ID on boot device
2072 37 common/cmd_doc.c correct chip ID found, device available
2073 -38 common/cmd_doc.c Read Error on boot device
2074 38 common/cmd_doc.c reading Image header from DOC device OK
2075 -39 common/cmd_doc.c Image header has bad magic number
2076 39 common/cmd_doc.c Image header has correct magic number
2077 -40 common/cmd_doc.c Error reading Image from DOC device
2078 40 common/cmd_doc.c Image header has correct magic number
2079 41 common/cmd_ide.c before loading a Image from a IDE device
2080 -42 common/cmd_ide.c Bad usage of "ide" command
2081 42 common/cmd_ide.c correct usage of "ide" command
2082 -43 common/cmd_ide.c No boot device
2083 43 common/cmd_ide.c boot device found
2084 -44 common/cmd_ide.c Device not available
2085 44 common/cmd_ide.c Device available
2086 -45 common/cmd_ide.c wrong partition selected
2087 45 common/cmd_ide.c partition selected
2088 -46 common/cmd_ide.c Unknown partition table
2089 46 common/cmd_ide.c valid partition table found
2090 -47 common/cmd_ide.c Invalid partition type
2091 47 common/cmd_ide.c correct partition type
2092 -48 common/cmd_ide.c Error reading Image Header on boot device
2093 48 common/cmd_ide.c reading Image Header from IDE device OK
2094 -49 common/cmd_ide.c Image header has bad magic number
2095 49 common/cmd_ide.c Image header has correct magic number
2096 -50 common/cmd_ide.c Image header has bad checksum
2097 50 common/cmd_ide.c Image header has correct checksum
2098 -51 common/cmd_ide.c Error reading Image from IDE device
2099 51 common/cmd_ide.c reading Image from IDE device OK
2100 52 common/cmd_nand.c before loading a Image from a NAND device
2101 -53 common/cmd_nand.c Bad usage of "nand" command
2102 53 common/cmd_nand.c correct usage of "nand" command
2103 -54 common/cmd_nand.c No boot device
2104 54 common/cmd_nand.c boot device found
2105 -55 common/cmd_nand.c Unknown Chip ID on boot device
2106 55 common/cmd_nand.c correct chip ID found, device available
2107 -56 common/cmd_nand.c Error reading Image Header on boot device
2108 56 common/cmd_nand.c reading Image Header from NAND device OK
2109 -57 common/cmd_nand.c Image header has bad magic number
2110 57 common/cmd_nand.c Image header has correct magic number
2111 -58 common/cmd_nand.c Error reading Image from NAND device
2112 58 common/cmd_nand.c reading Image from NAND device OK
2114 -60 common/env_common.c Environment has a bad CRC, using default
2116 64 net/eth.c starting with Ethernet configuration.
2117 -64 net/eth.c no Ethernet found.
2118 65 net/eth.c Ethernet found.
2120 -80 common/cmd_net.c usage wrong
2121 80 common/cmd_net.c before calling NetLoop()
2122 -81 common/cmd_net.c some error in NetLoop() occurred
2123 81 common/cmd_net.c NetLoop() back without error
2124 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2125 82 common/cmd_net.c trying automatic boot
2126 83 common/cmd_net.c running "source" command
2127 -83 common/cmd_net.c some error in automatic boot or "source" command
2128 84 common/cmd_net.c end without errors
2133 100 common/cmd_bootm.c Kernel FIT Image has correct format
2134 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2135 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2136 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2137 102 common/cmd_bootm.c Kernel unit name specified
2138 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2139 103 common/cmd_bootm.c Found configuration node
2140 104 common/cmd_bootm.c Got kernel subimage node offset
2141 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2142 105 common/cmd_bootm.c Kernel subimage hash verification OK
2143 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2144 106 common/cmd_bootm.c Architecture check OK
2145 -106 common/cmd_bootm.c Kernel subimage has wrong type
2146 107 common/cmd_bootm.c Kernel subimage type OK
2147 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2148 108 common/cmd_bootm.c Got kernel subimage data/size
2149 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2150 -109 common/cmd_bootm.c Can't get kernel subimage type
2151 -110 common/cmd_bootm.c Can't get kernel subimage comp
2152 -111 common/cmd_bootm.c Can't get kernel subimage os
2153 -112 common/cmd_bootm.c Can't get kernel subimage load address
2154 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2156 120 common/image.c Start initial ramdisk verification
2157 -120 common/image.c Ramdisk FIT image has incorrect format
2158 121 common/image.c Ramdisk FIT image has correct format
2159 122 common/image.c No ramdisk subimage unit name, using configuration
2160 -122 common/image.c Can't get configuration for ramdisk subimage
2161 123 common/image.c Ramdisk unit name specified
2162 -124 common/image.c Can't get ramdisk subimage node offset
2163 125 common/image.c Got ramdisk subimage node offset
2164 -125 common/image.c Ramdisk subimage hash verification failed
2165 126 common/image.c Ramdisk subimage hash verification OK
2166 -126 common/image.c Ramdisk subimage for unsupported architecture
2167 127 common/image.c Architecture check OK
2168 -127 common/image.c Can't get ramdisk subimage data/size
2169 128 common/image.c Got ramdisk subimage data/size
2170 129 common/image.c Can't get ramdisk load address
2171 -129 common/image.c Got ramdisk load address
2173 -130 common/cmd_doc.c Incorrect FIT image format
2174 131 common/cmd_doc.c FIT image format OK
2176 -140 common/cmd_ide.c Incorrect FIT image format
2177 141 common/cmd_ide.c FIT image format OK
2179 -150 common/cmd_nand.c Incorrect FIT image format
2180 151 common/cmd_nand.c FIT image format OK
2182 - Automatic software updates via TFTP server
2184 CONFIG_UPDATE_TFTP_CNT_MAX
2185 CONFIG_UPDATE_TFTP_MSEC_MAX
2187 These options enable and control the auto-update feature;
2188 for a more detailed description refer to doc/README.update.
2190 - MTD Support (mtdparts command, UBI support)
2193 Adds the MTD device infrastructure from the Linux kernel.
2194 Needed for mtdparts command support.
2196 CONFIG_MTD_PARTITIONS
2198 Adds the MTD partitioning infrastructure from the Linux
2199 kernel. Needed for UBI support.
2205 [so far only for SMDK2400 and TRAB boards]
2207 - Modem support enable:
2208 CONFIG_MODEM_SUPPORT
2210 - RTS/CTS Flow control enable:
2213 - Modem debug support:
2214 CONFIG_MODEM_SUPPORT_DEBUG
2216 Enables debugging stuff (char screen[1024], dbg())
2217 for modem support. Useful only with BDI2000.
2219 - Interrupt support (PPC):
2221 There are common interrupt_init() and timer_interrupt()
2222 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2223 for CPU specific initialization. interrupt_init_cpu()
2224 should set decrementer_count to appropriate value. If
2225 CPU resets decrementer automatically after interrupt
2226 (ppc4xx) it should set decrementer_count to zero.
2227 timer_interrupt() calls timer_interrupt_cpu() for CPU
2228 specific handling. If board has watchdog / status_led
2229 / other_activity_monitor it works automatically from
2230 general timer_interrupt().
2234 In the target system modem support is enabled when a
2235 specific key (key combination) is pressed during
2236 power-on. Otherwise U-Boot will boot normally
2237 (autoboot). The key_pressed() function is called from
2238 board_init(). Currently key_pressed() is a dummy
2239 function, returning 1 and thus enabling modem
2242 If there are no modem init strings in the
2243 environment, U-Boot proceed to autoboot; the
2244 previous output (banner, info printfs) will be
2247 See also: doc/README.Modem
2250 Configuration Settings:
2251 -----------------------
2253 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2254 undefine this when you're short of memory.
2256 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2257 width of the commands listed in the 'help' command output.
2259 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2260 prompt for user input.
2262 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2264 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2266 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2268 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2269 the application (usually a Linux kernel) when it is
2272 - CONFIG_SYS_BAUDRATE_TABLE:
2273 List of legal baudrate settings for this board.
2275 - CONFIG_SYS_CONSOLE_INFO_QUIET
2276 Suppress display of console information at boot.
2278 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2279 If the board specific function
2280 extern int overwrite_console (void);
2281 returns 1, the stdin, stderr and stdout are switched to the
2282 serial port, else the settings in the environment are used.
2284 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2285 Enable the call to overwrite_console().
2287 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2288 Enable overwrite of previous console environment settings.
2290 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2291 Begin and End addresses of the area used by the
2294 - CONFIG_SYS_ALT_MEMTEST:
2295 Enable an alternate, more extensive memory test.
2297 - CONFIG_SYS_MEMTEST_SCRATCH:
2298 Scratch address used by the alternate memory test
2299 You only need to set this if address zero isn't writeable
2301 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2302 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2303 this specified memory area will get subtracted from the top
2304 (end) of RAM and won't get "touched" at all by U-Boot. By
2305 fixing up gd->ram_size the Linux kernel should gets passed
2306 the now "corrected" memory size and won't touch it either.
2307 This should work for arch/ppc and arch/powerpc. Only Linux
2308 board ports in arch/powerpc with bootwrapper support that
2309 recalculate the memory size from the SDRAM controller setup
2310 will have to get fixed in Linux additionally.
2312 This option can be used as a workaround for the 440EPx/GRx
2313 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2316 WARNING: Please make sure that this value is a multiple of
2317 the Linux page size (normally 4k). If this is not the case,
2318 then the end address of the Linux memory will be located at a
2319 non page size aligned address and this could cause major
2322 - CONFIG_SYS_TFTP_LOADADDR:
2323 Default load address for network file downloads
2325 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2326 Enable temporary baudrate change while serial download
2328 - CONFIG_SYS_SDRAM_BASE:
2329 Physical start address of SDRAM. _Must_ be 0 here.
2331 - CONFIG_SYS_MBIO_BASE:
2332 Physical start address of Motherboard I/O (if using a
2335 - CONFIG_SYS_FLASH_BASE:
2336 Physical start address of Flash memory.
2338 - CONFIG_SYS_MONITOR_BASE:
2339 Physical start address of boot monitor code (set by
2340 make config files to be same as the text base address
2341 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2342 CONFIG_SYS_FLASH_BASE when booting from flash.
2344 - CONFIG_SYS_MONITOR_LEN:
2345 Size of memory reserved for monitor code, used to
2346 determine _at_compile_time_ (!) if the environment is
2347 embedded within the U-Boot image, or in a separate
2350 - CONFIG_SYS_MALLOC_LEN:
2351 Size of DRAM reserved for malloc() use.
2353 - CONFIG_SYS_BOOTM_LEN:
2354 Normally compressed uImages are limited to an
2355 uncompressed size of 8 MBytes. If this is not enough,
2356 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2357 to adjust this setting to your needs.
2359 - CONFIG_SYS_BOOTMAPSZ:
2360 Maximum size of memory mapped by the startup code of
2361 the Linux kernel; all data that must be processed by
2362 the Linux kernel (bd_info, boot arguments, FDT blob if
2363 used) must be put below this limit, unless "bootm_low"
2364 enviroment variable is defined and non-zero. In such case
2365 all data for the Linux kernel must be between "bootm_low"
2366 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2367 variable "bootm_mapsize" will override the value of
2368 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2369 then the value in "bootm_size" will be used instead.
2371 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2372 Enable initrd_high functionality. If defined then the
2373 initrd_high feature is enabled and the bootm ramdisk subcommand
2376 - CONFIG_SYS_BOOT_GET_CMDLINE:
2377 Enables allocating and saving kernel cmdline in space between
2378 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2380 - CONFIG_SYS_BOOT_GET_KBD:
2381 Enables allocating and saving a kernel copy of the bd_info in
2382 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2384 - CONFIG_SYS_MAX_FLASH_BANKS:
2385 Max number of Flash memory banks
2387 - CONFIG_SYS_MAX_FLASH_SECT:
2388 Max number of sectors on a Flash chip
2390 - CONFIG_SYS_FLASH_ERASE_TOUT:
2391 Timeout for Flash erase operations (in ms)
2393 - CONFIG_SYS_FLASH_WRITE_TOUT:
2394 Timeout for Flash write operations (in ms)
2396 - CONFIG_SYS_FLASH_LOCK_TOUT
2397 Timeout for Flash set sector lock bit operation (in ms)
2399 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2400 Timeout for Flash clear lock bits operation (in ms)
2402 - CONFIG_SYS_FLASH_PROTECTION
2403 If defined, hardware flash sectors protection is used
2404 instead of U-Boot software protection.
2406 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2408 Enable TFTP transfers directly to flash memory;
2409 without this option such a download has to be
2410 performed in two steps: (1) download to RAM, and (2)
2411 copy from RAM to flash.
2413 The two-step approach is usually more reliable, since
2414 you can check if the download worked before you erase
2415 the flash, but in some situations (when system RAM is
2416 too limited to allow for a temporary copy of the
2417 downloaded image) this option may be very useful.
2419 - CONFIG_SYS_FLASH_CFI:
2420 Define if the flash driver uses extra elements in the
2421 common flash structure for storing flash geometry.
2423 - CONFIG_FLASH_CFI_DRIVER
2424 This option also enables the building of the cfi_flash driver
2425 in the drivers directory
2427 - CONFIG_FLASH_CFI_MTD
2428 This option enables the building of the cfi_mtd driver
2429 in the drivers directory. The driver exports CFI flash
2432 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2433 Use buffered writes to flash.
2435 - CONFIG_FLASH_SPANSION_S29WS_N
2436 s29ws-n MirrorBit flash has non-standard addresses for buffered
2439 - CONFIG_SYS_FLASH_QUIET_TEST
2440 If this option is defined, the common CFI flash doesn't
2441 print it's warning upon not recognized FLASH banks. This
2442 is useful, if some of the configured banks are only
2443 optionally available.
2445 - CONFIG_FLASH_SHOW_PROGRESS
2446 If defined (must be an integer), print out countdown
2447 digits and dots. Recommended value: 45 (9..1) for 80
2448 column displays, 15 (3..1) for 40 column displays.
2450 - CONFIG_SYS_RX_ETH_BUFFER:
2451 Defines the number of Ethernet receive buffers. On some
2452 Ethernet controllers it is recommended to set this value
2453 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2454 buffers can be full shortly after enabling the interface
2455 on high Ethernet traffic.
2456 Defaults to 4 if not defined.
2458 - CONFIG_ENV_MAX_ENTRIES
2460 Maximum number of entries in the hash table that is used
2461 internally to store the environment settings. The default
2462 setting is supposed to be generous and should work in most
2463 cases. This setting can be used to tune behaviour; see
2464 lib/hashtable.c for details.
2466 The following definitions that deal with the placement and management
2467 of environment data (variable area); in general, we support the
2468 following configurations:
2470 - CONFIG_ENV_IS_IN_FLASH:
2472 Define this if the environment is in flash memory.
2474 a) The environment occupies one whole flash sector, which is
2475 "embedded" in the text segment with the U-Boot code. This
2476 happens usually with "bottom boot sector" or "top boot
2477 sector" type flash chips, which have several smaller
2478 sectors at the start or the end. For instance, such a
2479 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2480 such a case you would place the environment in one of the
2481 4 kB sectors - with U-Boot code before and after it. With
2482 "top boot sector" type flash chips, you would put the
2483 environment in one of the last sectors, leaving a gap
2484 between U-Boot and the environment.
2486 - CONFIG_ENV_OFFSET:
2488 Offset of environment data (variable area) to the
2489 beginning of flash memory; for instance, with bottom boot
2490 type flash chips the second sector can be used: the offset
2491 for this sector is given here.
2493 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2497 This is just another way to specify the start address of
2498 the flash sector containing the environment (instead of
2501 - CONFIG_ENV_SECT_SIZE:
2503 Size of the sector containing the environment.
2506 b) Sometimes flash chips have few, equal sized, BIG sectors.
2507 In such a case you don't want to spend a whole sector for
2512 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2513 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2514 of this flash sector for the environment. This saves
2515 memory for the RAM copy of the environment.
2517 It may also save flash memory if you decide to use this
2518 when your environment is "embedded" within U-Boot code,
2519 since then the remainder of the flash sector could be used
2520 for U-Boot code. It should be pointed out that this is
2521 STRONGLY DISCOURAGED from a robustness point of view:
2522 updating the environment in flash makes it always
2523 necessary to erase the WHOLE sector. If something goes
2524 wrong before the contents has been restored from a copy in
2525 RAM, your target system will be dead.
2527 - CONFIG_ENV_ADDR_REDUND
2528 CONFIG_ENV_SIZE_REDUND
2530 These settings describe a second storage area used to hold
2531 a redundant copy of the environment data, so that there is
2532 a valid backup copy in case there is a power failure during
2533 a "saveenv" operation.
2535 BE CAREFUL! Any changes to the flash layout, and some changes to the
2536 source code will make it necessary to adapt <board>/u-boot.lds*
2540 - CONFIG_ENV_IS_IN_NVRAM:
2542 Define this if you have some non-volatile memory device
2543 (NVRAM, battery buffered SRAM) which you want to use for the
2549 These two #defines are used to determine the memory area you
2550 want to use for environment. It is assumed that this memory
2551 can just be read and written to, without any special
2554 BE CAREFUL! The first access to the environment happens quite early
2555 in U-Boot initalization (when we try to get the setting of for the
2556 console baudrate). You *MUST* have mapped your NVRAM area then, or
2559 Please note that even with NVRAM we still use a copy of the
2560 environment in RAM: we could work on NVRAM directly, but we want to
2561 keep settings there always unmodified except somebody uses "saveenv"
2562 to save the current settings.
2565 - CONFIG_ENV_IS_IN_EEPROM:
2567 Use this if you have an EEPROM or similar serial access
2568 device and a driver for it.
2570 - CONFIG_ENV_OFFSET:
2573 These two #defines specify the offset and size of the
2574 environment area within the total memory of your EEPROM.
2576 - CONFIG_SYS_I2C_EEPROM_ADDR:
2577 If defined, specified the chip address of the EEPROM device.
2578 The default address is zero.
2580 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2581 If defined, the number of bits used to address bytes in a
2582 single page in the EEPROM device. A 64 byte page, for example
2583 would require six bits.
2585 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2586 If defined, the number of milliseconds to delay between
2587 page writes. The default is zero milliseconds.
2589 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2590 The length in bytes of the EEPROM memory array address. Note
2591 that this is NOT the chip address length!
2593 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2594 EEPROM chips that implement "address overflow" are ones
2595 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2596 address and the extra bits end up in the "chip address" bit
2597 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2600 Note that we consider the length of the address field to
2601 still be one byte because the extra address bits are hidden
2602 in the chip address.
2604 - CONFIG_SYS_EEPROM_SIZE:
2605 The size in bytes of the EEPROM device.
2607 - CONFIG_ENV_EEPROM_IS_ON_I2C
2608 define this, if you have I2C and SPI activated, and your
2609 EEPROM, which holds the environment, is on the I2C bus.
2611 - CONFIG_I2C_ENV_EEPROM_BUS
2612 if you have an Environment on an EEPROM reached over
2613 I2C muxes, you can define here, how to reach this
2614 EEPROM. For example:
2616 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2618 EEPROM which holds the environment, is reached over
2619 a pca9547 i2c mux with address 0x70, channel 3.
2621 - CONFIG_ENV_IS_IN_DATAFLASH:
2623 Define this if you have a DataFlash memory device which you
2624 want to use for the environment.
2626 - CONFIG_ENV_OFFSET:
2630 These three #defines specify the offset and size of the
2631 environment area within the total memory of your DataFlash placed
2632 at the specified address.
2634 - CONFIG_ENV_IS_IN_NAND:
2636 Define this if you have a NAND device which you want to use
2637 for the environment.
2639 - CONFIG_ENV_OFFSET:
2642 These two #defines specify the offset and size of the environment
2643 area within the first NAND device. CONFIG_ENV_OFFSET must be
2644 aligned to an erase block boundary.
2646 - CONFIG_ENV_OFFSET_REDUND (optional):
2648 This setting describes a second storage area of CONFIG_ENV_SIZE
2649 size used to hold a redundant copy of the environment data, so
2650 that there is a valid backup copy in case there is a power failure
2651 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2652 aligned to an erase block boundary.
2654 - CONFIG_ENV_RANGE (optional):
2656 Specifies the length of the region in which the environment
2657 can be written. This should be a multiple of the NAND device's
2658 block size. Specifying a range with more erase blocks than
2659 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2660 the range to be avoided.
2662 - CONFIG_ENV_OFFSET_OOB (optional):
2664 Enables support for dynamically retrieving the offset of the
2665 environment from block zero's out-of-band data. The
2666 "nand env.oob" command can be used to record this offset.
2667 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2668 using CONFIG_ENV_OFFSET_OOB.
2670 - CONFIG_NAND_ENV_DST
2672 Defines address in RAM to which the nand_spl code should copy the
2673 environment. If redundant environment is used, it will be copied to
2674 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2676 - CONFIG_SYS_SPI_INIT_OFFSET
2678 Defines offset to the initial SPI buffer area in DPRAM. The
2679 area is used at an early stage (ROM part) if the environment
2680 is configured to reside in the SPI EEPROM: We need a 520 byte
2681 scratch DPRAM area. It is used between the two initialization
2682 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2683 to be a good choice since it makes it far enough from the
2684 start of the data area as well as from the stack pointer.
2686 Please note that the environment is read-only until the monitor
2687 has been relocated to RAM and a RAM copy of the environment has been
2688 created; also, when using EEPROM you will have to use getenv_f()
2689 until then to read environment variables.
2691 The environment is protected by a CRC32 checksum. Before the monitor
2692 is relocated into RAM, as a result of a bad CRC you will be working
2693 with the compiled-in default environment - *silently*!!! [This is
2694 necessary, because the first environment variable we need is the
2695 "baudrate" setting for the console - if we have a bad CRC, we don't
2696 have any device yet where we could complain.]
2698 Note: once the monitor has been relocated, then it will complain if
2699 the default environment is used; a new CRC is computed as soon as you
2700 use the "saveenv" command to store a valid environment.
2702 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2703 Echo the inverted Ethernet link state to the fault LED.
2705 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2706 also needs to be defined.
2708 - CONFIG_SYS_FAULT_MII_ADDR:
2709 MII address of the PHY to check for the Ethernet link state.
2711 - CONFIG_NS16550_MIN_FUNCTIONS:
2712 Define this if you desire to only have use of the NS16550_init
2713 and NS16550_putc functions for the serial driver located at
2714 drivers/serial/ns16550.c. This option is useful for saving
2715 space for already greatly restricted images, including but not
2716 limited to NAND_SPL configurations.
2718 Low Level (hardware related) configuration options:
2719 ---------------------------------------------------
2721 - CONFIG_SYS_CACHELINE_SIZE:
2722 Cache Line Size of the CPU.
2724 - CONFIG_SYS_DEFAULT_IMMR:
2725 Default address of the IMMR after system reset.
2727 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2728 and RPXsuper) to be able to adjust the position of
2729 the IMMR register after a reset.
2731 - Floppy Disk Support:
2732 CONFIG_SYS_FDC_DRIVE_NUMBER
2734 the default drive number (default value 0)
2736 CONFIG_SYS_ISA_IO_STRIDE
2738 defines the spacing between FDC chipset registers
2741 CONFIG_SYS_ISA_IO_OFFSET
2743 defines the offset of register from address. It
2744 depends on which part of the data bus is connected to
2745 the FDC chipset. (default value 0)
2747 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2748 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2751 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2752 fdc_hw_init() is called at the beginning of the FDC
2753 setup. fdc_hw_init() must be provided by the board
2754 source code. It is used to make hardware dependant
2757 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2758 DO NOT CHANGE unless you know exactly what you're
2759 doing! (11-4) [MPC8xx/82xx systems only]
2761 - CONFIG_SYS_INIT_RAM_ADDR:
2763 Start address of memory area that can be used for
2764 initial data and stack; please note that this must be
2765 writable memory that is working WITHOUT special
2766 initialization, i. e. you CANNOT use normal RAM which
2767 will become available only after programming the
2768 memory controller and running certain initialization
2771 U-Boot uses the following memory types:
2772 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2773 - MPC824X: data cache
2774 - PPC4xx: data cache
2776 - CONFIG_SYS_GBL_DATA_OFFSET:
2778 Offset of the initial data structure in the memory
2779 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2780 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2781 data is located at the end of the available space
2782 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
2783 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2784 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2785 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2788 On the MPC824X (or other systems that use the data
2789 cache for initial memory) the address chosen for
2790 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2791 point to an otherwise UNUSED address space between
2792 the top of RAM and the start of the PCI space.
2794 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2796 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2798 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2800 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2802 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2804 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2806 - CONFIG_SYS_OR_TIMING_SDRAM:
2809 - CONFIG_SYS_MAMR_PTA:
2810 periodic timer for refresh
2812 - CONFIG_SYS_DER: Debug Event Register (37-47)
2814 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2815 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2816 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2817 CONFIG_SYS_BR1_PRELIM:
2818 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2820 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2821 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2822 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2823 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2825 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2826 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2827 Machine Mode Register and Memory Periodic Timer
2828 Prescaler definitions (SDRAM timing)
2830 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2831 enable I2C microcode relocation patch (MPC8xx);
2832 define relocation offset in DPRAM [DSP2]
2834 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2835 enable SMC microcode relocation patch (MPC8xx);
2836 define relocation offset in DPRAM [SMC1]
2838 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2839 enable SPI microcode relocation patch (MPC8xx);
2840 define relocation offset in DPRAM [SCC4]
2842 - CONFIG_SYS_USE_OSCCLK:
2843 Use OSCM clock mode on MBX8xx board. Be careful,
2844 wrong setting might damage your board. Read
2845 doc/README.MBX before setting this variable!
2847 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2848 Offset of the bootmode word in DPRAM used by post
2849 (Power On Self Tests). This definition overrides
2850 #define'd default value in commproc.h resp.
2853 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2854 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2855 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2856 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2857 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2858 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2859 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2860 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2861 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
2863 - CONFIG_PCI_DISABLE_PCIE:
2864 Disable PCI-Express on systems where it is supported but not
2868 Chip has SRIO or not
2871 Board has SRIO 1 port available
2874 Board has SRIO 2 port available
2876 - CONFIG_SYS_SRIOn_MEM_VIRT:
2877 Virtual Address of SRIO port 'n' memory region
2879 - CONFIG_SYS_SRIOn_MEM_PHYS:
2880 Physical Address of SRIO port 'n' memory region
2882 - CONFIG_SYS_SRIOn_MEM_SIZE:
2883 Size of SRIO port 'n' memory region
2886 Get DDR timing information from an I2C EEPROM. Common
2887 with pluggable memory modules such as SODIMMs
2890 I2C address of the SPD EEPROM
2892 - CONFIG_SYS_SPD_BUS_NUM
2893 If SPD EEPROM is on an I2C bus other than the first
2894 one, specify here. Note that the value must resolve
2895 to something your driver can deal with.
2897 - CONFIG_SYS_83XX_DDR_USES_CS0
2898 Only for 83xx systems. If specified, then DDR should
2899 be configured using CS0 and CS1 instead of CS2 and CS3.
2901 - CONFIG_ETHER_ON_FEC[12]
2902 Define to enable FEC[12] on a 8xx series processor.
2904 - CONFIG_FEC[12]_PHY
2905 Define to the hardcoded PHY address which corresponds
2906 to the given FEC; i. e.
2907 #define CONFIG_FEC1_PHY 4
2908 means that the PHY with address 4 is connected to FEC1
2910 When set to -1, means to probe for first available.
2912 - CONFIG_FEC[12]_PHY_NORXERR
2913 The PHY does not have a RXERR line (RMII only).
2914 (so program the FEC to ignore it).
2917 Enable RMII mode for all FECs.
2918 Note that this is a global option, we can't
2919 have one FEC in standard MII mode and another in RMII mode.
2921 - CONFIG_CRC32_VERIFY
2922 Add a verify option to the crc32 command.
2925 => crc32 -v <address> <count> <crc32>
2927 Where address/count indicate a memory area
2928 and crc32 is the correct crc32 which the
2932 Add the "loopw" memory command. This only takes effect if
2933 the memory commands are activated globally (CONFIG_CMD_MEM).
2936 Add the "mdc" and "mwc" memory commands. These are cyclic
2941 This command will print 4 bytes (10,11,12,13) each 500 ms.
2943 => mwc.l 100 12345678 10
2944 This command will write 12345678 to address 100 all 10 ms.
2946 This only takes effect if the memory commands are activated
2947 globally (CONFIG_CMD_MEM).
2949 - CONFIG_SKIP_LOWLEVEL_INIT
2950 [ARM only] If this variable is defined, then certain
2951 low level initializations (like setting up the memory
2952 controller) are omitted and/or U-Boot does not
2953 relocate itself into RAM.
2955 Normally this variable MUST NOT be defined. The only
2956 exception is when U-Boot is loaded (to RAM) by some
2957 other boot loader or by a debugger which performs
2958 these initializations itself.
2961 Modifies the behaviour of start.S when compiling a loader
2962 that is executed before the actual U-Boot. E.g. when
2963 compiling a NAND SPL.
2965 - CONFIG_USE_ARCH_MEMCPY
2966 CONFIG_USE_ARCH_MEMSET
2967 If these options are used a optimized version of memcpy/memset will
2968 be used if available. These functions may be faster under some
2969 conditions but may increase the binary size.
2971 Building the Software:
2972 ======================
2974 Building U-Boot has been tested in several native build environments
2975 and in many different cross environments. Of course we cannot support
2976 all possibly existing versions of cross development tools in all
2977 (potentially obsolete) versions. In case of tool chain problems we
2978 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
2979 which is extensively used to build and test U-Boot.
2981 If you are not using a native environment, it is assumed that you
2982 have GNU cross compiling tools available in your path. In this case,
2983 you must set the environment variable CROSS_COMPILE in your shell.
2984 Note that no changes to the Makefile or any other source files are
2985 necessary. For example using the ELDK on a 4xx CPU, please enter:
2987 $ CROSS_COMPILE=ppc_4xx-
2988 $ export CROSS_COMPILE
2990 Note: If you wish to generate Windows versions of the utilities in
2991 the tools directory you can use the MinGW toolchain
2992 (http://www.mingw.org). Set your HOST tools to the MinGW
2993 toolchain and execute 'make tools'. For example:
2995 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
2997 Binaries such as tools/mkimage.exe will be created which can
2998 be executed on computers running Windows.
3000 U-Boot is intended to be simple to build. After installing the
3001 sources you must configure U-Boot for one specific board type. This
3006 where "NAME_config" is the name of one of the existing configu-
3007 rations; see the main Makefile for supported names.
3009 Note: for some board special configuration names may exist; check if
3010 additional information is available from the board vendor; for
3011 instance, the TQM823L systems are available without (standard)
3012 or with LCD support. You can select such additional "features"
3013 when choosing the configuration, i. e.
3016 - will configure for a plain TQM823L, i. e. no LCD support
3018 make TQM823L_LCD_config
3019 - will configure for a TQM823L with U-Boot console on LCD
3024 Finally, type "make all", and you should get some working U-Boot
3025 images ready for download to / installation on your system:
3027 - "u-boot.bin" is a raw binary image
3028 - "u-boot" is an image in ELF binary format
3029 - "u-boot.srec" is in Motorola S-Record format
3031 By default the build is performed locally and the objects are saved
3032 in the source directory. One of the two methods can be used to change
3033 this behavior and build U-Boot to some external directory:
3035 1. Add O= to the make command line invocations:
3037 make O=/tmp/build distclean
3038 make O=/tmp/build NAME_config
3039 make O=/tmp/build all
3041 2. Set environment variable BUILD_DIR to point to the desired location:
3043 export BUILD_DIR=/tmp/build
3048 Note that the command line "O=" setting overrides the BUILD_DIR environment
3052 Please be aware that the Makefiles assume you are using GNU make, so
3053 for instance on NetBSD you might need to use "gmake" instead of
3057 If the system board that you have is not listed, then you will need
3058 to port U-Boot to your hardware platform. To do this, follow these
3061 1. Add a new configuration option for your board to the toplevel
3062 "Makefile" and to the "MAKEALL" script, using the existing
3063 entries as examples. Note that here and at many other places
3064 boards and other names are listed in alphabetical sort order. Please
3066 2. Create a new directory to hold your board specific code. Add any
3067 files you need. In your board directory, you will need at least
3068 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3069 3. Create a new configuration file "include/configs/<board>.h" for
3071 3. If you're porting U-Boot to a new CPU, then also create a new
3072 directory to hold your CPU specific code. Add any files you need.
3073 4. Run "make <board>_config" with your new name.
3074 5. Type "make", and you should get a working "u-boot.srec" file
3075 to be installed on your target system.
3076 6. Debug and solve any problems that might arise.
3077 [Of course, this last step is much harder than it sounds.]
3080 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3081 ==============================================================
3083 If you have modified U-Boot sources (for instance added a new board
3084 or support for new devices, a new CPU, etc.) you are expected to
3085 provide feedback to the other developers. The feedback normally takes
3086 the form of a "patch", i. e. a context diff against a certain (latest
3087 official or latest in the git repository) version of U-Boot sources.
3089 But before you submit such a patch, please verify that your modifi-
3090 cation did not break existing code. At least make sure that *ALL* of
3091 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3092 just run the "MAKEALL" script, which will configure and build U-Boot
3093 for ALL supported system. Be warned, this will take a while. You can
3094 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3095 environment variable to the script, i. e. to use the ELDK cross tools
3098 CROSS_COMPILE=ppc_8xx- MAKEALL
3100 or to build on a native PowerPC system you can type
3102 CROSS_COMPILE=' ' MAKEALL
3104 When using the MAKEALL script, the default behaviour is to build
3105 U-Boot in the source directory. This location can be changed by
3106 setting the BUILD_DIR environment variable. Also, for each target
3107 built, the MAKEALL script saves two log files (<target>.ERR and
3108 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3109 location can be changed by setting the MAKEALL_LOGDIR environment
3110 variable. For example:
3112 export BUILD_DIR=/tmp/build
3113 export MAKEALL_LOGDIR=/tmp/log
3114 CROSS_COMPILE=ppc_8xx- MAKEALL
3116 With the above settings build objects are saved in the /tmp/build,
3117 log files are saved in the /tmp/log and the source tree remains clean
3118 during the whole build process.
3121 See also "U-Boot Porting Guide" below.
3124 Monitor Commands - Overview:
3125 ============================
3127 go - start application at address 'addr'
3128 run - run commands in an environment variable
3129 bootm - boot application image from memory
3130 bootp - boot image via network using BootP/TFTP protocol
3131 tftpboot- boot image via network using TFTP protocol
3132 and env variables "ipaddr" and "serverip"
3133 (and eventually "gatewayip")
3134 rarpboot- boot image via network using RARP/TFTP protocol
3135 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3136 loads - load S-Record file over serial line
3137 loadb - load binary file over serial line (kermit mode)
3139 mm - memory modify (auto-incrementing)
3140 nm - memory modify (constant address)
3141 mw - memory write (fill)
3143 cmp - memory compare
3144 crc32 - checksum calculation
3145 i2c - I2C sub-system
3146 sspi - SPI utility commands
3147 base - print or set address offset
3148 printenv- print environment variables
3149 setenv - set environment variables
3150 saveenv - save environment variables to persistent storage
3151 protect - enable or disable FLASH write protection
3152 erase - erase FLASH memory
3153 flinfo - print FLASH memory information
3154 bdinfo - print Board Info structure
3155 iminfo - print header information for application image
3156 coninfo - print console devices and informations
3157 ide - IDE sub-system
3158 loop - infinite loop on address range
3159 loopw - infinite write loop on address range
3160 mtest - simple RAM test
3161 icache - enable or disable instruction cache
3162 dcache - enable or disable data cache
3163 reset - Perform RESET of the CPU
3164 echo - echo args to console
3165 version - print monitor version
3166 help - print online help
3167 ? - alias for 'help'
3170 Monitor Commands - Detailed Description:
3171 ========================================
3175 For now: just type "help <command>".
3178 Environment Variables:
3179 ======================
3181 U-Boot supports user configuration using Environment Variables which
3182 can be made persistent by saving to Flash memory.
3184 Environment Variables are set using "setenv", printed using
3185 "printenv", and saved to Flash using "saveenv". Using "setenv"
3186 without a value can be used to delete a variable from the
3187 environment. As long as you don't save the environment you are
3188 working with an in-memory copy. In case the Flash area containing the
3189 environment is erased by accident, a default environment is provided.
3191 Some configuration options can be set using Environment Variables.
3193 List of environment variables (most likely not complete):
3195 baudrate - see CONFIG_BAUDRATE
3197 bootdelay - see CONFIG_BOOTDELAY
3199 bootcmd - see CONFIG_BOOTCOMMAND
3201 bootargs - Boot arguments when booting an RTOS image
3203 bootfile - Name of the image to load with TFTP
3205 bootm_low - Memory range available for image processing in the bootm
3206 command can be restricted. This variable is given as
3207 a hexadecimal number and defines lowest address allowed
3208 for use by the bootm command. See also "bootm_size"
3209 environment variable. Address defined by "bootm_low" is
3210 also the base of the initial memory mapping for the Linux
3211 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3214 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3215 This variable is given as a hexadecimal number and it
3216 defines the size of the memory region starting at base
3217 address bootm_low that is accessible by the Linux kernel
3218 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3219 as the default value if it is defined, and bootm_size is
3222 bootm_size - Memory range available for image processing in the bootm
3223 command can be restricted. This variable is given as
3224 a hexadecimal number and defines the size of the region
3225 allowed for use by the bootm command. See also "bootm_low"
3226 environment variable.
3228 updatefile - Location of the software update file on a TFTP server, used
3229 by the automatic software update feature. Please refer to
3230 documentation in doc/README.update for more details.
3232 autoload - if set to "no" (any string beginning with 'n'),
3233 "bootp" will just load perform a lookup of the
3234 configuration from the BOOTP server, but not try to
3235 load any image using TFTP
3237 autostart - if set to "yes", an image loaded using the "bootp",
3238 "rarpboot", "tftpboot" or "diskboot" commands will
3239 be automatically started (by internally calling
3242 If set to "no", a standalone image passed to the
3243 "bootm" command will be copied to the load address
3244 (and eventually uncompressed), but NOT be started.
3245 This can be used to load and uncompress arbitrary
3248 i2cfast - (PPC405GP|PPC405EP only)
3249 if set to 'y' configures Linux I2C driver for fast
3250 mode (400kHZ). This environment variable is used in
3251 initialization code. So, for changes to be effective
3252 it must be saved and board must be reset.
3254 initrd_high - restrict positioning of initrd images:
3255 If this variable is not set, initrd images will be
3256 copied to the highest possible address in RAM; this
3257 is usually what you want since it allows for
3258 maximum initrd size. If for some reason you want to
3259 make sure that the initrd image is loaded below the
3260 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3261 variable to a value of "no" or "off" or "0".
3262 Alternatively, you can set it to a maximum upper
3263 address to use (U-Boot will still check that it
3264 does not overwrite the U-Boot stack and data).
3266 For instance, when you have a system with 16 MB
3267 RAM, and want to reserve 4 MB from use by Linux,
3268 you can do this by adding "mem=12M" to the value of
3269 the "bootargs" variable. However, now you must make
3270 sure that the initrd image is placed in the first
3271 12 MB as well - this can be done with
3273 setenv initrd_high 00c00000
3275 If you set initrd_high to 0xFFFFFFFF, this is an
3276 indication to U-Boot that all addresses are legal
3277 for the Linux kernel, including addresses in flash
3278 memory. In this case U-Boot will NOT COPY the
3279 ramdisk at all. This may be useful to reduce the
3280 boot time on your system, but requires that this
3281 feature is supported by your Linux kernel.
3283 ipaddr - IP address; needed for tftpboot command
3285 loadaddr - Default load address for commands like "bootp",
3286 "rarpboot", "tftpboot", "loadb" or "diskboot"
3288 loads_echo - see CONFIG_LOADS_ECHO
3290 serverip - TFTP server IP address; needed for tftpboot command
3292 bootretry - see CONFIG_BOOT_RETRY_TIME
3294 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3296 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3298 ethprime - When CONFIG_NET_MULTI is enabled controls which
3299 interface is used first.
3301 ethact - When CONFIG_NET_MULTI is enabled controls which
3302 interface is currently active. For example you
3303 can do the following
3305 => setenv ethact FEC
3306 => ping 192.168.0.1 # traffic sent on FEC
3307 => setenv ethact SCC
3308 => ping 10.0.0.1 # traffic sent on SCC
3310 ethrotate - When set to "no" U-Boot does not go through all
3311 available network interfaces.
3312 It just stays at the currently selected interface.
3314 netretry - When set to "no" each network operation will
3315 either succeed or fail without retrying.
3316 When set to "once" the network operation will
3317 fail when all the available network interfaces
3318 are tried once without success.
3319 Useful on scripts which control the retry operation
3322 npe_ucode - set load address for the NPE microcode
3324 tftpsrcport - If this is set, the value is used for TFTP's
3327 tftpdstport - If this is set, the value is used for TFTP's UDP
3328 destination port instead of the Well Know Port 69.
3330 tftpblocksize - Block size to use for TFTP transfers; if not set,
3331 we use the TFTP server's default block size
3333 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3334 seconds, minimum value is 1000 = 1 second). Defines
3335 when a packet is considered to be lost so it has to
3336 be retransmitted. The default is 5000 = 5 seconds.
3337 Lowering this value may make downloads succeed
3338 faster in networks with high packet loss rates or
3339 with unreliable TFTP servers.
3341 vlan - When set to a value < 4095 the traffic over
3342 Ethernet is encapsulated/received over 802.1q
3345 The following environment variables may be used and automatically
3346 updated by the network boot commands ("bootp" and "rarpboot"),
3347 depending the information provided by your boot server:
3349 bootfile - see above
3350 dnsip - IP address of your Domain Name Server
3351 dnsip2 - IP address of your secondary Domain Name Server
3352 gatewayip - IP address of the Gateway (Router) to use
3353 hostname - Target hostname
3355 netmask - Subnet Mask
3356 rootpath - Pathname of the root filesystem on the NFS server
3357 serverip - see above
3360 There are two special Environment Variables:
3362 serial# - contains hardware identification information such
3363 as type string and/or serial number
3364 ethaddr - Ethernet address
3366 These variables can be set only once (usually during manufacturing of
3367 the board). U-Boot refuses to delete or overwrite these variables
3368 once they have been set once.
3371 Further special Environment Variables:
3373 ver - Contains the U-Boot version string as printed
3374 with the "version" command. This variable is
3375 readonly (see CONFIG_VERSION_VARIABLE).
3378 Please note that changes to some configuration parameters may take
3379 only effect after the next boot (yes, that's just like Windoze :-).
3382 Command Line Parsing:
3383 =====================
3385 There are two different command line parsers available with U-Boot:
3386 the old "simple" one, and the much more powerful "hush" shell:
3388 Old, simple command line parser:
3389 --------------------------------
3391 - supports environment variables (through setenv / saveenv commands)
3392 - several commands on one line, separated by ';'
3393 - variable substitution using "... ${name} ..." syntax
3394 - special characters ('$', ';') can be escaped by prefixing with '\',
3396 setenv bootcmd bootm \${address}
3397 - You can also escape text by enclosing in single apostrophes, for example:
3398 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3403 - similar to Bourne shell, with control structures like
3404 if...then...else...fi, for...do...done; while...do...done,
3405 until...do...done, ...
3406 - supports environment ("global") variables (through setenv / saveenv
3407 commands) and local shell variables (through standard shell syntax
3408 "name=value"); only environment variables can be used with "run"
3414 (1) If a command line (or an environment variable executed by a "run"
3415 command) contains several commands separated by semicolon, and
3416 one of these commands fails, then the remaining commands will be
3419 (2) If you execute several variables with one call to run (i. e.
3420 calling run with a list of variables as arguments), any failing
3421 command will cause "run" to terminate, i. e. the remaining
3422 variables are not executed.
3424 Note for Redundant Ethernet Interfaces:
3425 =======================================
3427 Some boards come with redundant Ethernet interfaces; U-Boot supports
3428 such configurations and is capable of automatic selection of a
3429 "working" interface when needed. MAC assignment works as follows:
3431 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3432 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3433 "eth1addr" (=>eth1), "eth2addr", ...
3435 If the network interface stores some valid MAC address (for instance
3436 in SROM), this is used as default address if there is NO correspon-
3437 ding setting in the environment; if the corresponding environment
3438 variable is set, this overrides the settings in the card; that means:
3440 o If the SROM has a valid MAC address, and there is no address in the
3441 environment, the SROM's address is used.
3443 o If there is no valid address in the SROM, and a definition in the
3444 environment exists, then the value from the environment variable is
3447 o If both the SROM and the environment contain a MAC address, and
3448 both addresses are the same, this MAC address is used.
3450 o If both the SROM and the environment contain a MAC address, and the
3451 addresses differ, the value from the environment is used and a
3454 o If neither SROM nor the environment contain a MAC address, an error
3457 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3458 will be programmed into hardware as part of the initialization process. This
3459 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3460 The naming convention is as follows:
3461 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3466 U-Boot is capable of booting (and performing other auxiliary operations on)
3467 images in two formats:
3469 New uImage format (FIT)
3470 -----------------------
3472 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3473 to Flattened Device Tree). It allows the use of images with multiple
3474 components (several kernels, ramdisks, etc.), with contents protected by
3475 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3481 Old image format is based on binary files which can be basically anything,
3482 preceded by a special header; see the definitions in include/image.h for
3483 details; basically, the header defines the following image properties:
3485 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3486 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3487 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3488 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3490 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3491 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3492 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3493 * Compression Type (uncompressed, gzip, bzip2)
3499 The header is marked by a special Magic Number, and both the header
3500 and the data portions of the image are secured against corruption by
3507 Although U-Boot should support any OS or standalone application
3508 easily, the main focus has always been on Linux during the design of
3511 U-Boot includes many features that so far have been part of some
3512 special "boot loader" code within the Linux kernel. Also, any
3513 "initrd" images to be used are no longer part of one big Linux image;
3514 instead, kernel and "initrd" are separate images. This implementation
3515 serves several purposes:
3517 - the same features can be used for other OS or standalone
3518 applications (for instance: using compressed images to reduce the
3519 Flash memory footprint)
3521 - it becomes much easier to port new Linux kernel versions because
3522 lots of low-level, hardware dependent stuff are done by U-Boot
3524 - the same Linux kernel image can now be used with different "initrd"
3525 images; of course this also means that different kernel images can
3526 be run with the same "initrd". This makes testing easier (you don't
3527 have to build a new "zImage.initrd" Linux image when you just
3528 change a file in your "initrd"). Also, a field-upgrade of the
3529 software is easier now.
3535 Porting Linux to U-Boot based systems:
3536 ---------------------------------------
3538 U-Boot cannot save you from doing all the necessary modifications to
3539 configure the Linux device drivers for use with your target hardware
3540 (no, we don't intend to provide a full virtual machine interface to
3543 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3545 Just make sure your machine specific header file (for instance
3546 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3547 Information structure as we define in include/asm-<arch>/u-boot.h,
3548 and make sure that your definition of IMAP_ADDR uses the same value
3549 as your U-Boot configuration in CONFIG_SYS_IMMR.
3552 Configuring the Linux kernel:
3553 -----------------------------
3555 No specific requirements for U-Boot. Make sure you have some root
3556 device (initial ramdisk, NFS) for your target system.
3559 Building a Linux Image:
3560 -----------------------
3562 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3563 not used. If you use recent kernel source, a new build target
3564 "uImage" will exist which automatically builds an image usable by
3565 U-Boot. Most older kernels also have support for a "pImage" target,
3566 which was introduced for our predecessor project PPCBoot and uses a
3567 100% compatible format.
3576 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3577 encapsulate a compressed Linux kernel image with header information,
3578 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3580 * build a standard "vmlinux" kernel image (in ELF binary format):
3582 * convert the kernel into a raw binary image:
3584 ${CROSS_COMPILE}-objcopy -O binary \
3585 -R .note -R .comment \
3586 -S vmlinux linux.bin
3588 * compress the binary image:
3592 * package compressed binary image for U-Boot:
3594 mkimage -A ppc -O linux -T kernel -C gzip \
3595 -a 0 -e 0 -n "Linux Kernel Image" \
3596 -d linux.bin.gz uImage
3599 The "mkimage" tool can also be used to create ramdisk images for use
3600 with U-Boot, either separated from the Linux kernel image, or
3601 combined into one file. "mkimage" encapsulates the images with a 64
3602 byte header containing information about target architecture,
3603 operating system, image type, compression method, entry points, time
3604 stamp, CRC32 checksums, etc.
3606 "mkimage" can be called in two ways: to verify existing images and
3607 print the header information, or to build new images.
3609 In the first form (with "-l" option) mkimage lists the information
3610 contained in the header of an existing U-Boot image; this includes
3611 checksum verification:
3613 tools/mkimage -l image
3614 -l ==> list image header information
3616 The second form (with "-d" option) is used to build a U-Boot image
3617 from a "data file" which is used as image payload:
3619 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3620 -n name -d data_file image
3621 -A ==> set architecture to 'arch'
3622 -O ==> set operating system to 'os'
3623 -T ==> set image type to 'type'
3624 -C ==> set compression type 'comp'
3625 -a ==> set load address to 'addr' (hex)
3626 -e ==> set entry point to 'ep' (hex)
3627 -n ==> set image name to 'name'
3628 -d ==> use image data from 'datafile'
3630 Right now, all Linux kernels for PowerPC systems use the same load
3631 address (0x00000000), but the entry point address depends on the
3634 - 2.2.x kernels have the entry point at 0x0000000C,
3635 - 2.3.x and later kernels have the entry point at 0x00000000.
3637 So a typical call to build a U-Boot image would read:
3639 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3640 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3641 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3642 > examples/uImage.TQM850L
3643 Image Name: 2.4.4 kernel for TQM850L
3644 Created: Wed Jul 19 02:34:59 2000
3645 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3646 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3647 Load Address: 0x00000000
3648 Entry Point: 0x00000000
3650 To verify the contents of the image (or check for corruption):
3652 -> tools/mkimage -l examples/uImage.TQM850L
3653 Image Name: 2.4.4 kernel for TQM850L
3654 Created: Wed Jul 19 02:34:59 2000
3655 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3656 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3657 Load Address: 0x00000000
3658 Entry Point: 0x00000000
3660 NOTE: for embedded systems where boot time is critical you can trade
3661 speed for memory and install an UNCOMPRESSED image instead: this
3662 needs more space in Flash, but boots much faster since it does not
3663 need to be uncompressed:
3665 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3666 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3667 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3668 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3669 > examples/uImage.TQM850L-uncompressed
3670 Image Name: 2.4.4 kernel for TQM850L
3671 Created: Wed Jul 19 02:34:59 2000
3672 Image Type: PowerPC Linux Kernel Image (uncompressed)
3673 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3674 Load Address: 0x00000000
3675 Entry Point: 0x00000000
3678 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3679 when your kernel is intended to use an initial ramdisk:
3681 -> tools/mkimage -n 'Simple Ramdisk Image' \
3682 > -A ppc -O linux -T ramdisk -C gzip \
3683 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3684 Image Name: Simple Ramdisk Image
3685 Created: Wed Jan 12 14:01:50 2000
3686 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3687 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3688 Load Address: 0x00000000
3689 Entry Point: 0x00000000
3692 Installing a Linux Image:
3693 -------------------------
3695 To downloading a U-Boot image over the serial (console) interface,
3696 you must convert the image to S-Record format:
3698 objcopy -I binary -O srec examples/image examples/image.srec
3700 The 'objcopy' does not understand the information in the U-Boot
3701 image header, so the resulting S-Record file will be relative to
3702 address 0x00000000. To load it to a given address, you need to
3703 specify the target address as 'offset' parameter with the 'loads'
3706 Example: install the image to address 0x40100000 (which on the
3707 TQM8xxL is in the first Flash bank):
3709 => erase 40100000 401FFFFF
3715 ## Ready for S-Record download ...
3716 ~>examples/image.srec
3717 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3719 15989 15990 15991 15992
3720 [file transfer complete]
3722 ## Start Addr = 0x00000000
3725 You can check the success of the download using the 'iminfo' command;
3726 this includes a checksum verification so you can be sure no data
3727 corruption happened:
3731 ## Checking Image at 40100000 ...
3732 Image Name: 2.2.13 for initrd on TQM850L
3733 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3734 Data Size: 335725 Bytes = 327 kB = 0 MB
3735 Load Address: 00000000
3736 Entry Point: 0000000c
3737 Verifying Checksum ... OK
3743 The "bootm" command is used to boot an application that is stored in
3744 memory (RAM or Flash). In case of a Linux kernel image, the contents
3745 of the "bootargs" environment variable is passed to the kernel as
3746 parameters. You can check and modify this variable using the
3747 "printenv" and "setenv" commands:
3750 => printenv bootargs
3751 bootargs=root=/dev/ram
3753 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3755 => printenv bootargs
3756 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3759 ## Booting Linux kernel at 40020000 ...
3760 Image Name: 2.2.13 for NFS on TQM850L
3761 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3762 Data Size: 381681 Bytes = 372 kB = 0 MB
3763 Load Address: 00000000
3764 Entry Point: 0000000c
3765 Verifying Checksum ... OK
3766 Uncompressing Kernel Image ... OK
3767 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
3768 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3769 time_init: decrementer frequency = 187500000/60
3770 Calibrating delay loop... 49.77 BogoMIPS
3771 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3774 If you want to boot a Linux kernel with initial RAM disk, you pass
3775 the memory addresses of both the kernel and the initrd image (PPBCOOT
3776 format!) to the "bootm" command:
3778 => imi 40100000 40200000
3780 ## Checking Image at 40100000 ...
3781 Image Name: 2.2.13 for initrd on TQM850L
3782 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3783 Data Size: 335725 Bytes = 327 kB = 0 MB
3784 Load Address: 00000000
3785 Entry Point: 0000000c
3786 Verifying Checksum ... OK
3788 ## Checking Image at 40200000 ...
3789 Image Name: Simple Ramdisk Image
3790 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3791 Data Size: 566530 Bytes = 553 kB = 0 MB
3792 Load Address: 00000000
3793 Entry Point: 00000000
3794 Verifying Checksum ... OK
3796 => bootm 40100000 40200000
3797 ## Booting Linux kernel at 40100000 ...
3798 Image Name: 2.2.13 for initrd on TQM850L
3799 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3800 Data Size: 335725 Bytes = 327 kB = 0 MB
3801 Load Address: 00000000
3802 Entry Point: 0000000c
3803 Verifying Checksum ... OK
3804 Uncompressing Kernel Image ... OK
3805 ## Loading RAMDisk Image at 40200000 ...
3806 Image Name: Simple Ramdisk Image
3807 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3808 Data Size: 566530 Bytes = 553 kB = 0 MB
3809 Load Address: 00000000
3810 Entry Point: 00000000
3811 Verifying Checksum ... OK
3812 Loading Ramdisk ... OK
3813 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
3814 Boot arguments: root=/dev/ram
3815 time_init: decrementer frequency = 187500000/60
3816 Calibrating delay loop... 49.77 BogoMIPS
3818 RAMDISK: Compressed image found at block 0
3819 VFS: Mounted root (ext2 filesystem).
3823 Boot Linux and pass a flat device tree:
3826 First, U-Boot must be compiled with the appropriate defines. See the section
3827 titled "Linux Kernel Interface" above for a more in depth explanation. The
3828 following is an example of how to start a kernel and pass an updated
3834 oft=oftrees/mpc8540ads.dtb
3835 => tftp $oftaddr $oft
3836 Speed: 1000, full duplex
3838 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3839 Filename 'oftrees/mpc8540ads.dtb'.
3840 Load address: 0x300000
3843 Bytes transferred = 4106 (100a hex)
3844 => tftp $loadaddr $bootfile
3845 Speed: 1000, full duplex
3847 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3849 Load address: 0x200000
3850 Loading:############
3852 Bytes transferred = 1029407 (fb51f hex)
3857 => bootm $loadaddr - $oftaddr
3858 ## Booting image at 00200000 ...
3859 Image Name: Linux-2.6.17-dirty
3860 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3861 Data Size: 1029343 Bytes = 1005.2 kB
3862 Load Address: 00000000
3863 Entry Point: 00000000
3864 Verifying Checksum ... OK
3865 Uncompressing Kernel Image ... OK
3866 Booting using flat device tree at 0x300000
3867 Using MPC85xx ADS machine description
3868 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3872 More About U-Boot Image Types:
3873 ------------------------------
3875 U-Boot supports the following image types:
3877 "Standalone Programs" are directly runnable in the environment
3878 provided by U-Boot; it is expected that (if they behave
3879 well) you can continue to work in U-Boot after return from
3880 the Standalone Program.
3881 "OS Kernel Images" are usually images of some Embedded OS which
3882 will take over control completely. Usually these programs
3883 will install their own set of exception handlers, device
3884 drivers, set up the MMU, etc. - this means, that you cannot
3885 expect to re-enter U-Boot except by resetting the CPU.
3886 "RAMDisk Images" are more or less just data blocks, and their
3887 parameters (address, size) are passed to an OS kernel that is
3889 "Multi-File Images" contain several images, typically an OS
3890 (Linux) kernel image and one or more data images like
3891 RAMDisks. This construct is useful for instance when you want
3892 to boot over the network using BOOTP etc., where the boot
3893 server provides just a single image file, but you want to get
3894 for instance an OS kernel and a RAMDisk image.
3896 "Multi-File Images" start with a list of image sizes, each
3897 image size (in bytes) specified by an "uint32_t" in network
3898 byte order. This list is terminated by an "(uint32_t)0".
3899 Immediately after the terminating 0 follow the images, one by
3900 one, all aligned on "uint32_t" boundaries (size rounded up to
3901 a multiple of 4 bytes).
3903 "Firmware Images" are binary images containing firmware (like
3904 U-Boot or FPGA images) which usually will be programmed to
3907 "Script files" are command sequences that will be executed by
3908 U-Boot's command interpreter; this feature is especially
3909 useful when you configure U-Boot to use a real shell (hush)
3910 as command interpreter.
3916 One of the features of U-Boot is that you can dynamically load and
3917 run "standalone" applications, which can use some resources of
3918 U-Boot like console I/O functions or interrupt services.
3920 Two simple examples are included with the sources:
3925 'examples/hello_world.c' contains a small "Hello World" Demo
3926 application; it is automatically compiled when you build U-Boot.
3927 It's configured to run at address 0x00040004, so you can play with it
3931 ## Ready for S-Record download ...
3932 ~>examples/hello_world.srec
3933 1 2 3 4 5 6 7 8 9 10 11 ...
3934 [file transfer complete]
3936 ## Start Addr = 0x00040004
3938 => go 40004 Hello World! This is a test.
3939 ## Starting application at 0x00040004 ...
3950 Hit any key to exit ...
3952 ## Application terminated, rc = 0x0
3954 Another example, which demonstrates how to register a CPM interrupt
3955 handler with the U-Boot code, can be found in 'examples/timer.c'.
3956 Here, a CPM timer is set up to generate an interrupt every second.
3957 The interrupt service routine is trivial, just printing a '.'
3958 character, but this is just a demo program. The application can be
3959 controlled by the following keys:
3961 ? - print current values og the CPM Timer registers
3962 b - enable interrupts and start timer
3963 e - stop timer and disable interrupts
3964 q - quit application
3967 ## Ready for S-Record download ...
3968 ~>examples/timer.srec
3969 1 2 3 4 5 6 7 8 9 10 11 ...
3970 [file transfer complete]
3972 ## Start Addr = 0x00040004
3975 ## Starting application at 0x00040004 ...
3978 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3981 [q, b, e, ?] Set interval 1000000 us
3984 [q, b, e, ?] ........
3985 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3988 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3991 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3994 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3996 [q, b, e, ?] ...Stopping timer
3998 [q, b, e, ?] ## Application terminated, rc = 0x0
4004 Over time, many people have reported problems when trying to use the
4005 "minicom" terminal emulation program for serial download. I (wd)
4006 consider minicom to be broken, and recommend not to use it. Under
4007 Unix, I recommend to use C-Kermit for general purpose use (and
4008 especially for kermit binary protocol download ("loadb" command), and
4009 use "cu" for S-Record download ("loads" command).
4011 Nevertheless, if you absolutely want to use it try adding this
4012 configuration to your "File transfer protocols" section:
4014 Name Program Name U/D FullScr IO-Red. Multi
4015 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4016 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4022 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4023 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4025 Building requires a cross environment; it is known to work on
4026 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4027 need gmake since the Makefiles are not compatible with BSD make).
4028 Note that the cross-powerpc package does not install include files;
4029 attempting to build U-Boot will fail because <machine/ansi.h> is
4030 missing. This file has to be installed and patched manually:
4032 # cd /usr/pkg/cross/powerpc-netbsd/include
4034 # ln -s powerpc machine
4035 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4036 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4038 Native builds *don't* work due to incompatibilities between native
4039 and U-Boot include files.
4041 Booting assumes that (the first part of) the image booted is a
4042 stage-2 loader which in turn loads and then invokes the kernel
4043 proper. Loader sources will eventually appear in the NetBSD source
4044 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4045 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4048 Implementation Internals:
4049 =========================
4051 The following is not intended to be a complete description of every
4052 implementation detail. However, it should help to understand the
4053 inner workings of U-Boot and make it easier to port it to custom
4057 Initial Stack, Global Data:
4058 ---------------------------
4060 The implementation of U-Boot is complicated by the fact that U-Boot
4061 starts running out of ROM (flash memory), usually without access to
4062 system RAM (because the memory controller is not initialized yet).
4063 This means that we don't have writable Data or BSS segments, and BSS
4064 is not initialized as zero. To be able to get a C environment working
4065 at all, we have to allocate at least a minimal stack. Implementation
4066 options for this are defined and restricted by the CPU used: Some CPU
4067 models provide on-chip memory (like the IMMR area on MPC8xx and
4068 MPC826x processors), on others (parts of) the data cache can be
4069 locked as (mis-) used as memory, etc.
4071 Chris Hallinan posted a good summary of these issues to the
4072 U-Boot mailing list:
4074 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4075 From: "Chris Hallinan" <clh@net1plus.com>
4076 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4079 Correct me if I'm wrong, folks, but the way I understand it
4080 is this: Using DCACHE as initial RAM for Stack, etc, does not
4081 require any physical RAM backing up the cache. The cleverness
4082 is that the cache is being used as a temporary supply of
4083 necessary storage before the SDRAM controller is setup. It's
4084 beyond the scope of this list to explain the details, but you
4085 can see how this works by studying the cache architecture and
4086 operation in the architecture and processor-specific manuals.
4088 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4089 is another option for the system designer to use as an
4090 initial stack/RAM area prior to SDRAM being available. Either
4091 option should work for you. Using CS 4 should be fine if your
4092 board designers haven't used it for something that would
4093 cause you grief during the initial boot! It is frequently not
4096 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4097 with your processor/board/system design. The default value
4098 you will find in any recent u-boot distribution in
4099 walnut.h should work for you. I'd set it to a value larger
4100 than your SDRAM module. If you have a 64MB SDRAM module, set
4101 it above 400_0000. Just make sure your board has no resources
4102 that are supposed to respond to that address! That code in
4103 start.S has been around a while and should work as is when
4104 you get the config right.
4109 It is essential to remember this, since it has some impact on the C
4110 code for the initialization procedures:
4112 * Initialized global data (data segment) is read-only. Do not attempt
4115 * Do not use any uninitialized global data (or implicitely initialized
4116 as zero data - BSS segment) at all - this is undefined, initiali-
4117 zation is performed later (when relocating to RAM).
4119 * Stack space is very limited. Avoid big data buffers or things like
4122 Having only the stack as writable memory limits means we cannot use
4123 normal global data to share information beween the code. But it
4124 turned out that the implementation of U-Boot can be greatly
4125 simplified by making a global data structure (gd_t) available to all
4126 functions. We could pass a pointer to this data as argument to _all_
4127 functions, but this would bloat the code. Instead we use a feature of
4128 the GCC compiler (Global Register Variables) to share the data: we
4129 place a pointer (gd) to the global data into a register which we
4130 reserve for this purpose.
4132 When choosing a register for such a purpose we are restricted by the
4133 relevant (E)ABI specifications for the current architecture, and by
4134 GCC's implementation.
4136 For PowerPC, the following registers have specific use:
4138 R2: reserved for system use
4139 R3-R4: parameter passing and return values
4140 R5-R10: parameter passing
4141 R13: small data area pointer
4145 (U-Boot also uses R12 as internal GOT pointer. r12
4146 is a volatile register so r12 needs to be reset when
4147 going back and forth between asm and C)
4149 ==> U-Boot will use R2 to hold a pointer to the global data
4151 Note: on PPC, we could use a static initializer (since the
4152 address of the global data structure is known at compile time),
4153 but it turned out that reserving a register results in somewhat
4154 smaller code - although the code savings are not that big (on
4155 average for all boards 752 bytes for the whole U-Boot image,
4156 624 text + 127 data).
4158 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4159 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4161 ==> U-Boot will use P3 to hold a pointer to the global data
4163 On ARM, the following registers are used:
4165 R0: function argument word/integer result
4166 R1-R3: function argument word
4168 R10: stack limit (used only if stack checking if enabled)
4169 R11: argument (frame) pointer
4170 R12: temporary workspace
4173 R15: program counter
4175 ==> U-Boot will use R8 to hold a pointer to the global data
4177 On Nios II, the ABI is documented here:
4178 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4180 ==> U-Boot will use gp to hold a pointer to the global data
4182 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4183 to access small data sections, so gp is free.
4185 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4186 or current versions of GCC may "optimize" the code too much.
4191 U-Boot runs in system state and uses physical addresses, i.e. the
4192 MMU is not used either for address mapping nor for memory protection.
4194 The available memory is mapped to fixed addresses using the memory
4195 controller. In this process, a contiguous block is formed for each
4196 memory type (Flash, SDRAM, SRAM), even when it consists of several
4197 physical memory banks.
4199 U-Boot is installed in the first 128 kB of the first Flash bank (on
4200 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4201 booting and sizing and initializing DRAM, the code relocates itself
4202 to the upper end of DRAM. Immediately below the U-Boot code some
4203 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4204 configuration setting]. Below that, a structure with global Board
4205 Info data is placed, followed by the stack (growing downward).
4207 Additionally, some exception handler code is copied to the low 8 kB
4208 of DRAM (0x00000000 ... 0x00001FFF).
4210 So a typical memory configuration with 16 MB of DRAM could look like
4213 0x0000 0000 Exception Vector code
4216 0x0000 2000 Free for Application Use
4222 0x00FB FF20 Monitor Stack (Growing downward)
4223 0x00FB FFAC Board Info Data and permanent copy of global data
4224 0x00FC 0000 Malloc Arena
4227 0x00FE 0000 RAM Copy of Monitor Code
4228 ... eventually: LCD or video framebuffer
4229 ... eventually: pRAM (Protected RAM - unchanged by reset)
4230 0x00FF FFFF [End of RAM]
4233 System Initialization:
4234 ----------------------
4236 In the reset configuration, U-Boot starts at the reset entry point
4237 (on most PowerPC systems at address 0x00000100). Because of the reset
4238 configuration for CS0# this is a mirror of the onboard Flash memory.
4239 To be able to re-map memory U-Boot then jumps to its link address.
4240 To be able to implement the initialization code in C, a (small!)
4241 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4242 which provide such a feature like MPC8xx or MPC8260), or in a locked
4243 part of the data cache. After that, U-Boot initializes the CPU core,
4244 the caches and the SIU.
4246 Next, all (potentially) available memory banks are mapped using a
4247 preliminary mapping. For example, we put them on 512 MB boundaries
4248 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4249 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4250 programmed for SDRAM access. Using the temporary configuration, a
4251 simple memory test is run that determines the size of the SDRAM
4254 When there is more than one SDRAM bank, and the banks are of
4255 different size, the largest is mapped first. For equal size, the first
4256 bank (CS2#) is mapped first. The first mapping is always for address
4257 0x00000000, with any additional banks following immediately to create
4258 contiguous memory starting from 0.
4260 Then, the monitor installs itself at the upper end of the SDRAM area
4261 and allocates memory for use by malloc() and for the global Board
4262 Info data; also, the exception vector code is copied to the low RAM
4263 pages, and the final stack is set up.
4265 Only after this relocation will you have a "normal" C environment;
4266 until that you are restricted in several ways, mostly because you are
4267 running from ROM, and because the code will have to be relocated to a
4271 U-Boot Porting Guide:
4272 ----------------------
4274 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4278 int main(int argc, char *argv[])
4280 sighandler_t no_more_time;
4282 signal(SIGALRM, no_more_time);
4283 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4285 if (available_money > available_manpower) {
4286 Pay consultant to port U-Boot;
4290 Download latest U-Boot source;
4292 Subscribe to u-boot mailing list;
4295 email("Hi, I am new to U-Boot, how do I get started?");
4298 Read the README file in the top level directory;
4299 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4300 Read applicable doc/*.README;
4301 Read the source, Luke;
4302 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4305 if (available_money > toLocalCurrency ($2500))
4308 Add a lot of aggravation and time;
4310 if (a similar board exists) { /* hopefully... */
4311 cp -a board/<similar> board/<myboard>
4312 cp include/configs/<similar>.h include/configs/<myboard>.h
4314 Create your own board support subdirectory;
4315 Create your own board include/configs/<myboard>.h file;
4317 Edit new board/<myboard> files
4318 Edit new include/configs/<myboard>.h
4323 Add / modify source code;
4327 email("Hi, I am having problems...");
4329 Send patch file to the U-Boot email list;
4330 if (reasonable critiques)
4331 Incorporate improvements from email list code review;
4333 Defend code as written;
4339 void no_more_time (int sig)
4348 All contributions to U-Boot should conform to the Linux kernel
4349 coding style; see the file "Documentation/CodingStyle" and the script
4350 "scripts/Lindent" in your Linux kernel source directory. In sources
4351 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4352 spaces before parameters to function calls) is actually used.
4354 Source files originating from a different project (for example the
4355 MTD subsystem) are generally exempt from these guidelines and are not
4356 reformated to ease subsequent migration to newer versions of those
4359 Please note that U-Boot is implemented in C (and to some small parts in
4360 Assembler); no C++ is used, so please do not use C++ style comments (//)
4363 Please also stick to the following formatting rules:
4364 - remove any trailing white space
4365 - use TAB characters for indentation, not spaces
4366 - make sure NOT to use DOS '\r\n' line feeds
4367 - do not add more than 2 empty lines to source files
4368 - do not add trailing empty lines to source files
4370 Submissions which do not conform to the standards may be returned
4371 with a request to reformat the changes.
4377 Since the number of patches for U-Boot is growing, we need to
4378 establish some rules. Submissions which do not conform to these rules
4379 may be rejected, even when they contain important and valuable stuff.
4381 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4383 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4384 see http://lists.denx.de/mailman/listinfo/u-boot
4386 When you send a patch, please include the following information with
4389 * For bug fixes: a description of the bug and how your patch fixes
4390 this bug. Please try to include a way of demonstrating that the
4391 patch actually fixes something.
4393 * For new features: a description of the feature and your
4396 * A CHANGELOG entry as plaintext (separate from the patch)
4398 * For major contributions, your entry to the CREDITS file
4400 * When you add support for a new board, don't forget to add this
4401 board to the MAKEALL script, too.
4403 * If your patch adds new configuration options, don't forget to
4404 document these in the README file.
4406 * The patch itself. If you are using git (which is *strongly*
4407 recommended) you can easily generate the patch using the
4408 "git-format-patch". If you then use "git-send-email" to send it to
4409 the U-Boot mailing list, you will avoid most of the common problems
4410 with some other mail clients.
4412 If you cannot use git, use "diff -purN OLD NEW". If your version of
4413 diff does not support these options, then get the latest version of
4416 The current directory when running this command shall be the parent
4417 directory of the U-Boot source tree (i. e. please make sure that
4418 your patch includes sufficient directory information for the
4421 We prefer patches as plain text. MIME attachments are discouraged,
4422 and compressed attachments must not be used.
4424 * If one logical set of modifications affects or creates several
4425 files, all these changes shall be submitted in a SINGLE patch file.
4427 * Changesets that contain different, unrelated modifications shall be
4428 submitted as SEPARATE patches, one patch per changeset.
4433 * Before sending the patch, run the MAKEALL script on your patched
4434 source tree and make sure that no errors or warnings are reported
4435 for any of the boards.
4437 * Keep your modifications to the necessary minimum: A patch
4438 containing several unrelated changes or arbitrary reformats will be
4439 returned with a request to re-formatting / split it.
4441 * If you modify existing code, make sure that your new code does not
4442 add to the memory footprint of the code ;-) Small is beautiful!
4443 When adding new features, these should compile conditionally only
4444 (using #ifdef), and the resulting code with the new feature
4445 disabled must not need more memory than the old code without your
4448 * Remember that there is a size limit of 100 kB per message on the
4449 u-boot mailing list. Bigger patches will be moderated. If they are
4450 reasonable and not too big, they will be acknowledged. But patches
4451 bigger than the size limit should be avoided.
projects / platform / kernel / u-boot.git / blob