2 # (C) Copyright 2000 - 2002
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 and ARM processors, which can be
29 installed in a boot ROM and used to initialize and test the hardware
30 or to download and run application code.
32 The development of U-Boot is closely related to Linux: some parts of
33 the source code originate in the Linux source tree, we have some
34 header files in common, and special provision has been made to
35 support booting of Linux images.
37 Some attention has been paid to make this software easily
38 configurable and extendable. For instance, all monitor commands are
39 implemented with the same call interface, so that it's very easy to
40 add new commands. Also, instead of permanently adding rarely used
41 code (for instance hardware test utilities) to the monitor, you can
42 load and run it dynamically.
48 In general, all boards for which a configuration option exists in the
49 Makefile have been tested to some extent and can be considered
50 "working". In fact, many of them are used in production systems.
52 In case of problems see the CHANGELOG and CREDITS files to find out
53 who contributed the specific port.
59 In case you have questions about, problems with or contributions for
60 U-Boot you should send a message to the U-Boot mailing list at
61 <u-boot-users@lists.sourceforge.net>. There is also an archive of
62 previous traffic on the mailing list - please search the archive
63 before asking FAQ's. Please see
64 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
70 - start from 8xxrom sources
71 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
73 - make it easier to add custom boards
74 - make it possible to add other [PowerPC] CPUs
75 - extend functions, especially:
76 * Provide extended interface to Linux boot loader
79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
80 - create ARMBoot project (http://sourceforge.net/projects/armboot)
81 - add other CPU families (starting with ARM)
82 - create U-Boot project (http://sourceforge.net/projects/u-boot)
88 The "official" name of this project is "Das U-Boot". The spelling
89 "U-Boot" shall be used in all written text (documentation, comments
90 in source files etc.). Example:
92 This is the README file for the U-Boot project.
94 File names etc. shall be based on the string "u-boot". Examples:
96 include/asm-ppc/u-boot.h
98 #include <asm/u-boot.h>
100 Variable names, preprocessor constants etc. shall be either based on
101 the string "u_boot" or on "U_BOOT". Example:
103 U_BOOT_VERSION u_boot_logo
104 IH_OS_U_BOOT u_boot_hush_start
110 U-Boot uses a 3 level version number containing a version, a
111 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
112 sub-version "34", and patchlevel "4".
114 The patchlevel is used to indicate certain stages of development
115 between released versions, i. e. officially released versions of
116 U-Boot will always have a patchlevel of "0".
122 - board Board dependend files
123 - common Misc architecture independend functions
124 - cpu CPU specific files
125 - disk Code for disk drive partition handling
126 - doc Documentation (don't expect too much)
127 - drivers Common used device drivers
128 - dtt Digital Thermometer and Thermostat drivers
129 - examples Example code for standalone applications, etc.
130 - include Header Files
131 - disk Harddisk interface code
132 - net Networking code
133 - ppc Files generic to PowerPC architecture
134 - post Power On Self Test
135 - post/arch Symlink to architecture specific Power On Self Test
136 - post/arch-ppc PowerPC architecture specific Power On Self Test
137 - post/cpu/mpc8260 MPC8260 CPU specific Power On Self Test
138 - post/cpu/mpc8xx MPC8xx CPU specific Power On Self Test
139 - rtc Real Time Clock drivers
140 - tools Tools to build S-Record or U-Boot images, etc.
142 - cpu/74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
143 - cpu/mpc8xx Files specific to Motorola MPC8xx CPUs
144 - cpu/mpc824x Files specific to Motorola MPC824x CPUs
145 - cpu/mpc8260 Files specific to Motorola MPC8260 CPU
146 - cpu/ppc4xx Files specific to IBM 4xx CPUs
148 - board/LEOX/ Files specific to boards manufactured by The LEOX team
149 - board/LEOX/elpt860 Files specific to ELPT860 boards
151 Files specific to RPXClassic boards
152 - board/RPXlite Files specific to RPXlite boards
153 - board/c2mon Files specific to c2mon boards
154 - board/cogent Files specific to Cogent boards
155 (need further configuration)
156 Files specific to CPCIISER4 boards
157 - board/cpu86 Files specific to CPU86 boards
158 - board/cray/ Files specific to boards manufactured by Cray
159 - board/cray/L1 Files specific to L1 boards
160 - board/cu824 Files specific to CU824 boards
161 - board/ebony Files specific to IBM Ebony board
162 - board/eric Files specific to ERIC boards
163 - board/esd/ Files specific to boards manufactured by ESD
164 - board/esd/adciop Files specific to ADCIOP boards
165 - board/esd/ar405 Files specific to AR405 boards
166 - board/esd/canbt Files specific to CANBT boards
167 - board/esd/cpci405 Files specific to CPCI405 boards
168 - board/esd/cpciiser4 Files specific to CPCIISER4 boards
169 - board/esd/common Common files for ESD boards
170 - board/esd/dasa_sim Files specific to DASA_SIM boards
171 - board/esd/du405 Files specific to DU405 boards
172 - board/esd/ocrtc Files specific to OCRTC boards
173 - board/esd/pci405 Files specific to PCI405 boards
175 Files specific to ESTEEM192E boards
176 - board/etx094 Files specific to ETX_094 boards
178 Files specific to EVB64260 boards
179 - board/fads Files specific to FADS boards
180 - board/flagadm Files specific to FLAGADM boards
181 - board/gen860t Files specific to GEN860T boards
182 - board/genietv Files specific to GENIETV boards
183 - board/gth Files specific to GTH boards
184 - board/hermes Files specific to HERMES boards
185 - board/hymod Files specific to HYMOD boards
186 - board/icu862 Files specific to ICU862 boards
187 - board/ip860 Files specific to IP860 boards
189 Files specific to Interphase4539 boards
190 - board/ivm Files specific to IVMS8/IVML24 boards
191 - board/lantec Files specific to LANTEC boards
192 - board/lwmon Files specific to LWMON boards
193 - board/mbx8xx Files specific to MBX boards
195 Files specific to MMPC8260ADS boards
196 - board/mpl/ Files specific to boards manufactured by MPL
197 - board/mpl/common Common files for MPL boards
198 - board/mpl/pip405 Files specific to PIP405 boards
199 - board/mpl/mip405 Files specific to MIP405 boards
200 - board/musenki Files specific to MUSEKNI boards
201 - board/mvs1 Files specific to MVS1 boards
202 - board/nx823 Files specific to NX823 boards
203 - board/oxc Files specific to OXC boards
204 - board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards
205 - board/pm826 Files specific to PM826 boards
207 Files specific to PPMC8260 boards
209 Files specific to RPXsuper boards
211 Files specific to RSDproto boards
213 Files specific to Sandpoint boards
214 - board/sbc8260 Files specific to SBC8260 boards
215 - board/sacsng Files specific to SACSng boards
216 - board/siemens Files specific to boards manufactured by Siemens AG
217 - board/siemens/CCM Files specific to CCM boards
218 - board/siemens/IAD210 Files specific to IAD210 boards
219 - board/siemens/SCM Files specific to SCM boards
220 - board/siemens/pcu_e Files specific to PCU_E boards
221 - board/sixnet Files specific to SIXNET boards
222 - board/spd8xx Files specific to SPD8xxTS boards
223 - board/tqm8260 Files specific to TQM8260 boards
224 - board/tqm8xx Files specific to TQM8xxL boards
225 - board/w7o Files specific to W7O boards
227 Files specific to Walnut405 boards
228 - board/westel/ Files specific to boards manufactured by Westel Wireless
229 - board/westel/amx860 Files specific to AMX860 boards
230 - board/utx8245 Files specific to UTX8245 boards
232 Software Configuration:
233 =======================
235 Configuration is usually done using C preprocessor defines; the
236 rationale behind that is to avoid dead code whenever possible.
238 There are two classes of configuration variables:
240 * Configuration _OPTIONS_:
241 These are selectable by the user and have names beginning with
244 * Configuration _SETTINGS_:
245 These depend on the hardware etc. and should not be meddled with if
246 you don't know what you're doing; they have names beginning with
249 Later we will add a configuration tool - probably similar to or even
250 identical to what's used for the Linux kernel. Right now, we have to
251 do the configuration by hand, which means creating some symbolic
252 links and editing some configuration files. We use the TQM8xxL boards
256 Selection of Processor Architecture and Board Type:
257 ---------------------------------------------------
259 For all supported boards there are ready-to-use default
260 configurations available; just type "make <board_name>_config".
262 Example: For a TQM823L module type:
267 For the Cogent platform, you need to specify the cpu type as well;
268 e.g. "make cogent_mpc8xx_config". And also configure the cogent
269 directory according to the instructions in cogent/README.
272 Configuration Options:
273 ----------------------
275 Configuration depends on the combination of board and CPU type; all
276 such information is kept in a configuration file
277 "include/configs/<board_name>.h".
279 Example: For a TQM823L module, all configuration settings are in
280 "include/configs/TQM823L.h".
283 Many of the options are named exactly as the corresponding Linux
284 kernel configuration options. The intention is to make it easier to
285 build a config tool - later.
288 The following options need to be configured:
290 - CPU Type: Define exactly one of
294 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
295 or CONFIG_MPC824X, CONFIG_MPC8260
308 - Board Type: Define exactly one of
310 PowerPC based boards:
311 ---------------------
313 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper,
314 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850,
315 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS,
316 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T,
317 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240,
318 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245,
319 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L,
320 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L,
321 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L,
322 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L,
323 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260,
324 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech,
325 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245,
326 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC,
327 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG,
328 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405,
329 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA,
330 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon,
331 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260,
332 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx,
333 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260,
334 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260,
335 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes,
336 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod,
337 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon,
338 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e,
339 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260,
340 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto,
341 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260,
342 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L,
343 CONFIG_V37, CONFIG_ELPT860
348 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312,
349 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK,
350 CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410,
354 - CPU Module Type: (if CONFIG_COGENT is defined)
355 Define exactly one of
357 --- FIXME --- not tested yet:
358 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
359 CONFIG_CMA287_23, CONFIG_CMA287_50
361 - Motherboard Type: (if CONFIG_COGENT is defined)
362 Define exactly one of
363 CONFIG_CMA101, CONFIG_CMA102
365 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
366 Define one or more of
369 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
370 Define one or more of
371 CONFIG_LCD_HEARTBEAT - update a character position on
372 the lcd display every second with
375 - MPC824X Family Member (if CONFIG_MPC824X is defined)
376 Define exactly one of
377 CONFIG_MPC8240, CONFIG_MPC8245
379 - 8xx CPU Options: (if using an 8xx cpu)
380 Define one or more of
381 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() can not work e.g.
382 no 32KHz reference PIT/RTC clock
387 U-Boot stores all clock information in Hz
388 internally. For binary compatibility with older Linux
389 kernels (which expect the clocks passed in the
390 bd_info data to be in MHz) the environment variable
391 "clocks_in_mhz" can be defined so that U-Boot
392 converts clock data to MHZ before passing it to the
395 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
396 "clocks_in_mhz=1" is automatically included in the
400 Depending on board, define exactly one serial port
401 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
402 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
403 console by defining CONFIG_8xx_CONS_NONE
405 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
406 port routines must be defined elsewhere
407 (i.e. serial_init(), serial_getc(), ...)
410 Enables console device for a color framebuffer. Needs following
411 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
412 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
414 VIDEO_HW_RECTFILL graphic chip supports
417 VIDEO_HW_BITBLT graphic chip supports
418 bit-blit (cf. smiLynxEM)
419 VIDEO_VISIBLE_COLS visible pixel columns
421 VIDEO_VISIBLE_ROWS visible pixel rows
422 VIDEO_PIXEL_SIZE bytes per pixel
423 VIDEO_DATA_FORMAT graphic data format
424 (0-5, cf. cfb_console.c)
425 VIDEO_FB_ADRS framebuffer address
426 VIDEO_KBD_INIT_FCT keyboard int fct
427 (i.e. i8042_kbd_init())
428 VIDEO_TSTC_FCT test char fct
430 VIDEO_GETC_FCT get char fct
432 CONFIG_CONSOLE_CURSOR cursor drawing on/off
433 (requires blink timer
435 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
436 CONFIG_CONSOLE_TIME display time/date info in
438 (requires CFG_CMD_DATE)
439 CONFIG_VIDEO_LOGO display Linux logo in
441 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
442 linux_logo.h for logo.
443 Requires CONFIG_VIDEO_LOGO
444 CONFIG_CONSOLE_EXTRA_INFO
445 addional board info beside
448 When CONFIG_CFB_CONSOLE is defined, video console is
449 default i/o. Serial console can be forced with
450 environment 'console=serial'.
453 CONFIG_BAUDRATE - in bps
454 Select one of the baudrates listed in
455 CFG_BAUDRATE_TABLE, see below.
457 - Interrupt driven serial port input:
458 CONFIG_SERIAL_SOFTWARE_FIFO
461 Use an interrupt handler for receiving data on the
462 serial port. It also enables using hardware handshake
463 (RTS/CTS) and UART's built-in FIFO. Set the number of
464 bytes the interrupt driven input buffer should have.
466 Set to 0 to disable this feature (this is the default).
467 This will also disable hardware handshake.
469 - Boot Delay: CONFIG_BOOTDELAY - in seconds
470 Delay before automatically booting the default image;
471 set to -1 to disable autoboot.
473 See doc/README.autoboot for these options that
474 work with CONFIG_BOOTDELAY. None are required.
475 CONFIG_BOOT_RETRY_TIME
476 CONFIG_BOOT_RETRY_MIN
477 CONFIG_AUTOBOOT_KEYED
478 CONFIG_AUTOBOOT_PROMPT
479 CONFIG_AUTOBOOT_DELAY_STR
480 CONFIG_AUTOBOOT_STOP_STR
481 CONFIG_AUTOBOOT_DELAY_STR2
482 CONFIG_AUTOBOOT_STOP_STR2
483 CONFIG_ZERO_BOOTDELAY_CHECK
484 CONFIG_RESET_TO_RETRY
488 Only needed when CONFIG_BOOTDELAY is enabled;
489 define a command string that is automatically executed
490 when no character is read on the console interface
491 within "Boot Delay" after reset.
494 This can be used to pass arguments to the bootm
495 command. The value of CONFIG_BOOTARGS goes into the
496 environment value "bootargs".
498 CONFIG_RAMBOOT and CONFIG_NFSBOOT
499 The value of these goes into the environment as
500 "ramboot" and "nfsboot" respectively, and can be used
501 as a convenience, when switching between booting from
507 When this option is #defined, the existence of the
508 environment variable "preboot" will be checked
509 immediately before starting the CONFIG_BOOTDELAY
510 countdown and/or running the auto-boot command resp.
511 entering interactive mode.
513 This feature is especially useful when "preboot" is
514 automatically generated or modified. For an example
515 see the LWMON board specific code: here "preboot" is
516 modified when the user holds down a certain
517 combination of keys on the (special) keyboard when
520 - Serial Download Echo Mode:
522 If defined to 1, all characters received during a
523 serial download (using the "loads" command) are
524 echoed back. This might be needed by some terminal
525 emulations (like "cu"), but may as well just take
526 time on others. This setting #define's the initial
527 value of the "loads_echo" environment variable.
529 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
531 Select one of the baudrates listed in
532 CFG_BAUDRATE_TABLE, see below.
536 Most monitor functions can be selected (or
537 de-selected) by adjusting the definition of
538 CONFIG_COMMANDS; to select individual functions,
539 #define CONFIG_COMMANDS by "OR"ing any of the
542 #define enables commands:
543 -------------------------
544 CFG_CMD_ASKENV * ask for env variable
546 CFG_CMD_BEDBUG Include BedBug Debugger
548 CFG_CMD_CACHE icache, dcache
549 CFG_CMD_CONSOLE coninfo
550 CFG_CMD_DATE * support for RTC, date/time...
551 CFG_CMD_DHCP DHCP support
552 CFG_CMD_ECHO * echo arguments
553 CFG_CMD_EEPROM * EEPROM read/write support
554 CFG_CMD_ELF bootelf, bootvx
556 CFG_CMD_FDC * Floppy Disk Support
557 CFG_CMD_FDOS * Dos diskette Support
558 CFG_CMD_FLASH flinfo, erase, protect
559 CFG_CMD_FPGA FPGA device initialization support
560 CFG_CMD_I2C * I2C serial bus support
561 CFG_CMD_IDE * IDE harddisk support
563 CFG_CMD_IMMAP * IMMR dump support
564 CFG_CMD_IRQ * irqinfo
568 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
570 CFG_CMD_MII MII utility commands
571 CFG_CMD_NET bootp, tftpboot, rarpboot
572 CFG_CMD_PCI * pciinfo
573 CFG_CMD_PCMCIA * PCMCIA support
574 CFG_CMD_REGINFO * Register dump
575 CFG_CMD_RUN run command in env variable
576 CFG_CMD_SCSI * SCSI Support
577 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
578 CFG_CMD_SPI * SPI serial bus support
579 CFG_CMD_USB * USB support
580 CFG_CMD_BSP * Board SPecific functions
581 -----------------------------------------------
584 CFG_CMD_DFL Default configuration; at the moment
585 this is includes all commands, except
586 the ones marked with "*" in the list
589 If you don't define CONFIG_COMMANDS it defaults to
590 CFG_CMD_DFL in include/cmd_confdefs.h. A board can
591 override the default settings in the respective
594 EXAMPLE: If you want all functions except of network
595 support you can write:
597 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
600 Note: Don't enable the "icache" and "dcache" commands
601 (configuration option CFG_CMD_CACHE) unless you know
602 what you (and your U-Boot users) are doing. Data
603 cache cannot be enabled on systems like the 8xx or
604 8260 (where accesses to the IMMR region must be
605 uncached), and it cannot be disabled on all other
606 systems where we (mis-) use the data cache to hold an
607 initial stack and some data.
610 XXX - this list needs to get updated!
614 If this variable is defined, it enables watchdog
615 support. There must support in the platform specific
616 code for a watchdog. For the 8xx and 8260 CPUs, the
617 SIU Watchdog feature is enabled in the SYPCR
622 When CFG_CMD_DATE is selected, the type of the RTC
623 has to be selected, too. Define exactly one of the
626 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
627 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
628 CONFIG_RTC_MC146818 - use MC146818 RTC
629 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
630 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
631 CONFIG_RTC_DS164x - use Dallas DS164x RTC
635 When CONFIG_TIMESTAMP is selected, the timestamp
636 (date and time) of an image is printed by image
637 commands like bootm or iminfo. This option is
638 automatically enabled when you select CFG_CMD_DATE .
641 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
642 and/or CONFIG_ISO_PARTITION
644 If IDE or SCSI support is enabled (CFG_CMD_IDE or
645 CFG_CMD_SCSI) you must configure support for at least
646 one partition type as well.
649 CONFIG_IDE_RESET_ROUTINE
651 Set this to define that instead of a reset Pin, the
652 routine ide_set_reset(int idereset) will be used.
657 Set this to enable ATAPI support.
660 At the moment only there is only support for the
661 SYM53C8XX SCSI controller; define
662 CONFIG_SCSI_SYM53C8XX to enable it.
664 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
665 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
666 CFG_SCSI_MAX_LUN] can be adjusted to define the
667 maximum numbers of LUNs, SCSI ID's and target
669 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
671 - NETWORK Support (PCI):
673 Support for Intel 82557/82559/82559ER chips.
674 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
675 write routine for first time initialisation.
678 Support for Digital 2114x chips.
679 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
680 modem chip initialisation (KS8761/QS6611).
683 Support for National dp83815 chips.
686 Support for National dp8382[01] gigabit chips.
689 At the moment only the UHCI host controller is
690 supported (PIP405, MIP405); define
691 CONFIG_USB_UHCI to enable it.
692 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
693 end define CONFIG_USB_STORAGE to enable the USB
696 Supported are USB Keyboards and USB Floppy drives
702 Define this to enable standard (PC-Style) keyboard
706 Standard PC keyboard driver with US (is default) and
707 GERMAN key layout (switch via environment 'keymap=de') support.
708 Export function i8042_kbd_init, i8042_tstc and i8042_getc
709 for cfb_console. Supports cursor blinking.
714 Define this to enable video support (for output to
719 Enable Chips & Technologies 69000 Video chip
721 CONFIG_VIDEO_SMI_LYNXEM
722 Enable Silicon Motion SMI 712/710/810 Video chip
723 Videomode are selected via environment 'videomode' with
724 standard LiLo mode numbers.
725 Following modes are supported (* is default):
727 800x600 1024x768 1280x1024
728 256 (8bit) 303* 305 307
729 65536 (16bit) 314 317 31a
730 16,7 Mill (24bit) 315 318 31b
731 (i.e. setenv videomode 317; saveenv; reset;)
733 CONFIG_VIDEO_SED13806
734 Enable Epson SED13806 driver. This driver supports 8bpp
735 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
736 or CONFIG_VIDEO_SED13806_16BPP
739 - LCD Support: CONFIG_LCD
741 Define this to enable LCD support (for output to LCD
742 display); also select one of the supported displays
743 by defining one of these:
745 CONFIG_NEC_NL6648AC33:
747 NEC NL6648AC33-18. Active, color, single scan.
749 CONFIG_NEC_NL6648BC20
751 NEC NL6648BC20-08. 6.5", 640x480.
752 Active, color, single scan.
756 Sharp 320x240. Active, color, single scan.
757 It isn't 16x9, and I am not sure what it is.
759 CONFIG_SHARP_LQ64D341
761 Sharp LQ64D341 display, 640x480.
762 Active, color, single scan.
766 HLD1045 display, 640x480.
767 Active, color, single scan.
771 Optrex CBL50840-2 NF-FW 99 22 M5
773 Hitachi LMG6912RPFC-00T
777 320x240. Black & white.
779 Normally display is black on white background; define
780 CFG_WHITE_ON_BLACK to get it inverted.
787 Define a default value for ethernet address to use
788 for the respective ethernet interface, in case this
789 is not determined automatically.
794 Define a default value for the IP address to use for
795 the default ethernet interface, in case this is not
796 determined through e.g. bootp.
801 Defines a default value for theIP address of a TFTP
802 server to contact when using the "tftboot" command.
804 - BOOTP Recovery Mode:
805 CONFIG_BOOTP_RANDOM_DELAY
807 If you have many targets in a network that try to
808 boot using BOOTP, you may want to avoid that all
809 systems send out BOOTP requests at precisely the same
810 moment (which would happen for instance at recovery
811 from a power failure, when all systems will try to
812 boot, thus flooding the BOOTP server. Defining
813 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
814 inserted before sending out BOOTP requests. The
815 following delays are insterted then:
817 1st BOOTP request: delay 0 ... 1 sec
818 2nd BOOTP request: delay 0 ... 2 sec
819 3rd BOOTP request: delay 0 ... 4 sec
821 BOOTP requests: delay 0 ... 8 sec
823 - Status LED: CONFIG_STATUS_LED
825 Several configurations allow to display the current
826 status using a LED. For instance, the LED will blink
827 fast while running U-Boot code, stop blinking as
828 soon as a reply to a BOOTP request was received, and
829 start blinking slow once the Linux kernel is running
830 (supported by a status LED driver in the Linux
831 kernel). Defining CONFIG_STATUS_LED enables this
834 - CAN Support: CONFIG_CAN_DRIVER
836 Defining CONFIG_CAN_DRIVER enables CAN driver support
837 on those systems that support this (optional)
838 feature, like the TQM8xxL modules.
840 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
842 Enables I2C serial bus commands. If this is selected,
843 either CONFIG_HARD_I2C or CONFIG_SOFT_I2C must be defined
844 to include the appropriate I2C driver.
846 See also: common/cmd_i2c.c for a description of the
847 command line interface.
852 Selects the CPM hardware driver for I2C.
856 Use software (aka bit-banging) driver instead of CPM
857 or similar hardware support for I2C. This is configured
858 via the following defines.
862 (Optional). Any commands necessary to enable I2C
863 controller or configure ports.
867 (Only for MPC8260 CPU). The I/O port to use (the code
868 assumes both bits are on the same port). Valid values
869 are 0..3 for ports A..D.
873 The code necessary to make the I2C data line active
874 (driven). If the data line is open collector, this
879 The code necessary to make the I2C data line tri-stated
880 (inactive). If the data line is open collector, this
885 Code that returns TRUE if the I2C data line is high,
890 If <bit> is TRUE, sets the I2C data line high. If it
891 is FALSE, it clears it (low).
895 If <bit> is TRUE, sets the I2C clock line high. If it
896 is FALSE, it clears it (low).
900 This delay is invoked four times per clock cycle so this
901 controls the rate of data transfer. The data rate thus
902 is 1 / (I2C_DELAY * 4).
906 When a board is reset during an i2c bus transfer
907 chips might think that the current transfer is still
908 in progress. On some boards it is possible to access
909 the i2c SCLK line directly, either by using the
910 processor pin as a GPIO or by having a second pin
911 connected to the bus. If this option is defined a
912 custom i2c_init_board() routine in boards/xxx/board.c
913 is run early in the boot sequence.
915 - SPI Support: CONFIG_SPI
917 Enables SPI driver (so far only tested with
918 SPI EEPROM, also an instance works with Crystal A/D and
919 D/As on the SACSng board)
923 Enables extended (16-bit) SPI EEPROM addressing.
924 (symmetrical to CONFIG_I2C_X)
928 Enables a software (bit-bang) SPI driver rather than
929 using hardware support. This is a general purpose
930 driver that only requires three general I/O port pins
931 (two outputs, one input) to function. If this is
932 defined, the board configuration must define several
933 SPI configuration items (port pins to use, etc). For
934 an example, see include/configs/sacsng.h.
936 - FPGA Support: CONFIG_FPGA_COUNT
938 Specify the number of FPGA devices to support.
942 Used to specify the types of FPGA devices. For
944 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
946 CFG_FPGA_PROG_FEEDBACK
948 Enable printing of hash marks during FPGA
953 Enable checks on FPGA configuration interface busy
954 status by the configuration function. This option
955 will require a board or device specific function to
960 If defined, a function that provides delays in the
961 FPGA configuration driver.
965 Allow Control-C to interrupt FPGA configuration
969 Check for configuration errors during FPGA bitfile
970 loading. For example, abort during Virtex II
971 configuration if the INIT_B line goes low (which
972 indicated a CRC error).
976 Maximum time to wait for the INIT_B line to deassert
977 after PROB_B has been deasserted during a Virtex II
978 FPGA configuration sequence. The default time is 500 mS.
982 Maximum time to wait for BUSY to deassert during
983 Virtex II FPGA configuration. The default is 5 mS.
987 Time to wait after FPGA configuration. The default is
990 - FPGA Support: CONFIG_FPGA_COUNT
992 Specify the number of FPGA devices to support.
996 Used to specify the types of FPGA devices. For example,
997 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
999 CFG_FPGA_PROG_FEEDBACK
1001 Enable printing of hash marks during FPGA configuration.
1005 Enable checks on FPGA configuration interface busy
1006 status by the configuration function. This option
1007 will require a board or device specific function to
1012 If defined, a function that provides delays in the FPGA
1013 configuration driver.
1015 CFG_FPGA_CHECK_CTRLC
1016 Allow Control-C to interrupt FPGA configuration
1018 CFG_FPGA_CHECK_ERROR
1020 Check for configuration errors during FPGA bitfile
1021 loading. For example, abort during Virtex II
1022 configuration if the INIT_B line goes low (which
1023 indicated a CRC error).
1027 Maximum time to wait for the INIT_B line to deassert
1028 after PROB_B has been deasserted during a Virtex II
1029 FPGA configuration sequence. The default time is 500
1034 Maximum time to wait for BUSY to deassert during
1035 Virtex II FPGA configuration. The default is 5 mS.
1037 CFG_FPGA_WAIT_CONFIG
1039 Time to wait after FPGA configuration. The default is
1042 - Configuration Management:
1045 If defined, this string will be added to the U-Boot
1046 version information (U_BOOT_VERSION)
1048 - Vendor Parameter Protection:
1050 U-Boot considers the values of the environment
1051 variables "serial#" (Board Serial Number) and
1052 "ethaddr" (Ethernet Address) to bb parameters that
1053 are set once by the board vendor / manufacturer, and
1054 protects these variables from casual modification by
1055 the user. Once set, these variables are read-only,
1056 and write or delete attempts are rejected. You can
1057 change this behviour:
1059 If CONFIG_ENV_OVERWRITE is #defined in your config
1060 file, the write protection for vendor parameters is
1061 completely disabled. Anybody can change or delete
1064 Alternatively, if you #define _both_ CONFIG_ETHADDR
1065 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1066 ethernet address is installed in the environment,
1067 which can be changed exactly ONCE by the user. [The
1068 serial# is unaffected by this, i. e. it remains
1074 Define this variable to enable the reservation of
1075 "protected RAM", i. e. RAM which is not overwritten
1076 by U-Boot. Define CONFIG_PRAM to hold the number of
1077 kB you want to reserve for pRAM. You can overwrite
1078 this default value by defining an environment
1079 variable "pram" to the number of kB you want to
1080 reserve. Note that the board info structure will
1081 still show the full amount of RAM. If pRAM is
1082 reserved, a new environment variable "mem" will
1083 automatically be defined to hold the amount of
1084 remaining RAM in a form that can be passed as boot
1085 argument to Linux, for instance like that:
1087 setenv bootargs ... mem=\$(mem)
1090 This way you can tell Linux not to use this memory,
1091 either, which results in a memory region that will
1092 not be affected by reboots.
1094 *WARNING* If your board configuration uses automatic
1095 detection of the RAM size, you must make sure that
1096 this memory test is non-destructive. So far, the
1097 following board configurations are known to be
1100 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1101 HERMES, IP860, RPXlite, LWMON, LANTEC,
1102 PCU_E, FLAGADM, TQM8260
1107 Define this variable to stop the system in case of a
1108 fatal error, so that you have to reset it manually.
1109 This is probably NOT a good idea for an embedded
1110 system where you want to system to reboot
1111 automatically as fast as possible, but it may be
1112 useful during development since you can try to debug
1113 the conditions that lead to the situation.
1115 CONFIG_NET_RETRY_COUNT
1117 This variable defines the number of retries for
1118 network operations like ARP, RARP, TFTP, or BOOTP
1119 before giving up the operation. If not defined, a
1120 default value of 5 is used.
1122 - Command Interpreter:
1125 Define this variable to enable the "hush" shell (from
1126 Busybox) as command line interpreter, thus enabling
1127 powerful command line syntax like
1128 if...then...else...fi conditionals or `&&' and '||'
1129 constructs ("shell scripts").
1131 If undefined, you get the old, much simpler behaviour
1132 with a somewhat smaller memory footprint.
1137 This defines the secondary prompt string, which is
1138 printed when the command interpreter needs more input
1139 to complete a command. Usually "> ".
1143 In the current implementation, the local variables
1144 space and global environment variables space are
1145 separated. Local variables are those you define by
1146 simply typing like `name=value'. To access a local
1147 variable later on, you have write `$name' or
1148 `${name}'; variable directly by typing say `$name' at
1151 Global environment variables are those you use
1152 setenv/printenv to work with. To run a command stored
1153 in such a variable, you need to use the run command,
1154 and you must not use the '$' sign to access them.
1156 To store commands and special characters in a
1157 variable, please use double quotation marks
1158 surrounding the whole text of the variable, instead
1159 of the backslashes before semicolons and special
1162 - Default Environment
1163 CONFIG_EXTRA_ENV_SETTINGS
1165 Define this to contain any number of null terminated
1166 strings (variable = value pairs) that will be part of
1167 the default enviroment compiled into the boot image.
1169 For example, place something like this in your
1170 board's config file:
1172 #define CONFIG_EXTRA_ENV_SETTINGS \
1176 Warning: This method is based on knowledge about the
1177 internal format how the environment is stored by the
1178 U-Boot code. This is NOT an official, exported
1179 interface! Although it is unlikely that this format
1180 will change soon, but there is no guarantee either.
1181 You better know what you are doing here.
1183 Note: overly (ab)use of the default environment is
1184 discouraged. Make sure to check other ways to preset
1185 the environment like the autoscript function or the
1188 - Show boot progress
1189 CONFIG_SHOW_BOOT_PROGRESS
1191 Defining this option allows to add some board-
1192 specific code (calling a user-provided function
1193 "show_boot_progress(int)") that enables you to show
1194 the system's boot progress on some display (for
1195 example, some LED's) on your board. At the moment,
1196 the following checkpoints are implemented:
1199 1 common/cmd_bootm.c before attempting to boot an image
1200 -1 common/cmd_bootm.c Image header has bad magic number
1201 2 common/cmd_bootm.c Image header has correct magic number
1202 -2 common/cmd_bootm.c Image header has bad checksum
1203 3 common/cmd_bootm.c Image header has correct checksum
1204 -3 common/cmd_bootm.c Image data has bad checksum
1205 4 common/cmd_bootm.c Image data has correct checksum
1206 -4 common/cmd_bootm.c Image is for unsupported architecture
1207 5 common/cmd_bootm.c Architecture check OK
1208 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1209 6 common/cmd_bootm.c Image Type check OK
1210 -6 common/cmd_bootm.c gunzip uncompression error
1211 -7 common/cmd_bootm.c Unimplemented compression type
1212 7 common/cmd_bootm.c Uncompression OK
1213 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1214 8 common/cmd_bootm.c Image Type check OK
1215 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1216 9 common/cmd_bootm.c Start initial ramdisk verification
1217 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1218 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1219 10 common/cmd_bootm.c Ramdisk header is OK
1220 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1221 11 common/cmd_bootm.c Ramdisk data has correct checksum
1222 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1223 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1224 13 common/cmd_bootm.c Start multifile image verification
1225 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1226 15 common/cmd_bootm.c All preparation done, transferring control to OS
1228 -1 common/cmd_doc.c Bad usage of "doc" command
1229 -1 common/cmd_doc.c No boot device
1230 -1 common/cmd_doc.c Unknown Chip ID on boot device
1231 -1 common/cmd_doc.c Read Error on boot device
1232 -1 common/cmd_doc.c Image header has bad magic number
1234 -1 common/cmd_ide.c Bad usage of "ide" command
1235 -1 common/cmd_ide.c No boot device
1236 -1 common/cmd_ide.c Unknown boot device
1237 -1 common/cmd_ide.c Unknown partition table
1238 -1 common/cmd_ide.c Invalid partition type
1239 -1 common/cmd_ide.c Read Error on boot device
1240 -1 common/cmd_ide.c Image header has bad magic number
1242 -1 common/cmd_nvedit.c Environment not changable, but has bad CRC
1248 [so far only for SMDK2400 board]
1250 - Modem support endable:
1251 CONFIG_MODEM_SUPPORT
1253 - RTS/CTS Flow control enable:
1256 - Modem debug support:
1257 CONFIG_MODEM_SUPPORT_DEBUG
1259 Enables debugging stuff (char screen[1024], dbg())
1260 for modem support. Useful only with BDI2000.
1264 In the target system modem support is enabled when a
1265 specific key (key combination) is pressed during
1266 power-on. Otherwise U-Boot will boot normally
1267 (autoboot). The key_pressed() fuction is called from
1268 board_init(). Currently key_pressed() is a dummy
1269 function, returning 1 and thus enabling modem
1272 If there are no modem init strings in the
1273 environment, U-Boot proceed to autoboot; the
1274 previous output (banner, info printfs) will be
1277 See also: doc/README.Modem
1282 Configuration Settings:
1283 -----------------------
1285 - CFG_LONGHELP: Defined when you want long help messages included;
1286 undefine this when you're short of memory.
1288 - CFG_PROMPT: This is what U-Boot prints on the console to
1289 prompt for user input.
1291 - CFG_CBSIZE: Buffer size for input from the Console
1293 - CFG_PBSIZE: Buffer size for Console output
1295 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1297 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1298 the application (usually a Linux kernel) when it is
1301 - CFG_BAUDRATE_TABLE:
1302 List of legal baudrate settings for this board.
1304 - CFG_CONSOLE_INFO_QUIET
1305 Suppress display of console information at boot.
1307 - CFG_CONSOLE_IS_IN_ENV
1308 If the board specific function
1309 extern int overwrite_console (void);
1310 returns 1, the stdin, stderr and stdout are switched to the
1311 serial port, else the settings in the environment are used.
1313 - CFG_CONSOLE_OVERWRITE_ROUTINE
1314 Enable the call to overwrite_console().
1316 - CFG_CONSOLE_ENV_OVERWRITE
1317 Enable overwrite of previous console environment settings.
1319 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1320 Begin and End addresses of the area used by the
1324 Enable an alternate, more extensive memory test.
1326 - CFG_TFTP_LOADADDR:
1327 Default load address for network file downloads
1329 - CFG_LOADS_BAUD_CHANGE:
1330 Enable temporary baudrate change while serial download
1333 Physical start address of SDRAM. _Must_ be 0 here.
1336 Physical start address of Motherboard I/O (if using a
1340 Physical start address of Flash memory.
1343 Physical start address of boot monitor code (set by
1344 make config files to be same as the text base address
1345 (TEXT_BASE) used when linking) - same as
1346 CFG_FLASH_BASE when booting from flash.
1349 Size of memory reserved for monitor code
1352 Size of DRAM reserved for malloc() use.
1355 Maximum size of memory mapped by the startup code of
1356 the Linux kernel; all data that must be processed by
1357 the Linux kernel (bd_info, boot arguments, eventually
1358 initrd image) must be put below this limit.
1360 - CFG_MAX_FLASH_BANKS:
1361 Max number of Flash memory banks
1363 - CFG_MAX_FLASH_SECT:
1364 Max number of sectors on a Flash chip
1366 - CFG_FLASH_ERASE_TOUT:
1367 Timeout for Flash erase operations (in ms)
1369 - CFG_FLASH_WRITE_TOUT:
1370 Timeout for Flash write operations (in ms)
1372 - CFG_DIRECT_FLASH_TFTP:
1374 Enable TFTP transfers directly to flash memory;
1375 without this option such a download has to be
1376 performed in two steps: (1) download to RAM, and (2)
1377 copy from RAM to flash.
1379 The two-step approach is usually more reliable, since
1380 you can check if the download worked before you erase
1381 the flash, but in some situations (when sytem RAM is
1382 too limited to allow for a tempory copy of the
1383 downloaded image) this option may be very useful.
1386 Define if the flash driver uses extra elements in the
1387 common flash structure for storing flash geometry
1389 The following definitions that deal with the placement and management
1390 of environment data (variable area); in general, we support the
1391 following configurations:
1393 - CFG_ENV_IS_IN_FLASH:
1395 Define this if the environment is in flash memory.
1397 a) The environment occupies one whole flash sector, which is
1398 "embedded" in the text segment with the U-Boot code. This
1399 happens usually with "bottom boot sector" or "top boot
1400 sector" type flash chips, which have several smaller
1401 sectors at the start or the end. For instance, such a
1402 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1403 such a case you would place the environment in one of the
1404 4 kB sectors - with U-Boot code before and after it. With
1405 "top boot sector" type flash chips, you would put the
1406 environment in one of the last sectors, leaving a gap
1407 between U-Boot and the environment.
1411 Offset of environment data (variable area) to the
1412 beginning of flash memory; for instance, with bottom boot
1413 type flash chips the second sector can be used: the offset
1414 for this sector is given here.
1416 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1420 This is just another way to specify the start address of
1421 the flash sector containing the environment (instead of
1424 - CFG_ENV_SECT_SIZE:
1426 Size of the sector containing the environment.
1429 b) Sometimes flash chips have few, equal sized, BIG sectors.
1430 In such a case you don't want to spend a whole sector for
1435 If you use this in combination with CFG_ENV_IS_IN_FLASH
1436 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1437 of this flash sector for the environment. This saves
1438 memory for the RAM copy of the environment.
1440 It may also save flash memory if you decide to use this
1441 when your environment is "embedded" within U-Boot code,
1442 since then the remainder of the flash sector could be used
1443 for U-Boot code. It should be pointed out that this is
1444 STRONGLY DISCOURAGED from a robustness point of view:
1445 updating the environment in flash makes it always
1446 necessary to erase the WHOLE sector. If something goes
1447 wrong before the contents has been restored from a copy in
1448 RAM, your target system will be dead.
1450 - CFG_ENV_ADDR_REDUND
1453 These settings describe a second storage area used to hold
1454 a redundand copy of the environment data, so that there is
1455 a valid backup copy in case there is a power failur during
1456 a "saveenv" operation.
1458 BE CAREFUL! Any changes to the flash layout, and some changes to the
1459 source code will make it necessary to adapt <board>/u-boot.lds*
1463 - CFG_ENV_IS_IN_NVRAM:
1465 Define this if you have some non-volatile memory device
1466 (NVRAM, battery buffered SRAM) which you want to use for the
1472 These two #defines are used to determin the memory area you
1473 want to use for environment. It is assumed that this memory
1474 can just be read and written to, without any special
1477 BE CAREFUL! The first access to the environment happens quite early
1478 in U-Boot initalization (when we try to get the setting of for the
1479 console baudrate). You *MUST* have mappend your NVRAM area then, or
1482 Please note that even with NVRAM we still use a copy of the
1483 environment in RAM: we could work on NVRAM directly, but we want to
1484 keep settings there always unmodified except somebody uses "saveenv"
1485 to save the current settings.
1488 - CFG_ENV_IS_IN_EEPROM:
1490 Use this if you have an EEPROM or similar serial access
1491 device and a driver for it.
1496 These two #defines specify the offset and size of the
1497 environment area within the total memory of your EEPROM.
1499 - CFG_I2C_EEPROM_ADDR:
1500 If defined, specified the chip address of the EEPROM device.
1501 The default address is zero.
1503 - CFG_EEPROM_PAGE_WRITE_BITS:
1504 If defined, the number of bits used to address bytes in a
1505 single page in the EEPROM device. A 64 byte page, for example
1506 would require six bits.
1508 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1509 If defined, the number of milliseconds to delay between
1510 page writes. The default is zero milliseconds.
1512 - CFG_I2C_EEPROM_ADDR_LEN:
1513 The length in bytes of the EEPROM memory array address. Note
1514 that this is NOT the chip address length!
1517 The size in bytes of the EEPROM device.
1520 - CFG_SPI_INIT_OFFSET
1522 Defines offset to the initial SPI buffer area in DPRAM. The
1523 area is used at an early stage (ROM part) if the environment
1524 is configured to reside in the SPI EEPROM: We need a 520 byte
1525 scratch DPRAM area. It is used between the two initialization
1526 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1527 to be a good choice since it makes it far enough from the
1528 start of the data area as well as from the stack pointer.
1530 Please note that the environment is read-only as long as the monitor
1531 has been relocated to RAM and a RAM copy of the environment has been
1532 created; also, when using EEPROM you will have to use getenv_r()
1533 until then to read environment variables.
1535 The environment is now protected by a CRC32 checksum. Before the
1536 monitor is relocated into RAM, as a result of a bad CRC you will be
1537 working with the compiled-in default environment - *silently*!!!
1538 [This is necessary, because the first environment variable we need is
1539 the "baudrate" setting for the console - if we have a bad CRC, we
1540 don't have any device yet where we could complain.]
1542 Note: once the monitor has been relocated, then it will complain if
1543 the default environment is used; a new CRC is computed as soon as you
1544 use the "setenv" command to modify / delete / add any environment
1545 variable [even when you try to delete a non-existing variable!].
1547 Note2: you must edit your u-boot.lds file to reflect this
1551 Low Level (hardware related) configuration options:
1553 - CFG_CACHELINE_SIZE:
1554 Cache Line Size of the CPU.
1557 Default address of the IMMR after system reset.
1558 Needed on some 8260 systems (MPC8260ADS and RPXsuper)
1559 to be able to adjust the position of the IMMR
1560 register after a reset.
1562 - Floppy Disk Support:
1563 CFG_FDC_DRIVE_NUMBER
1565 the default drive number (default value 0)
1569 defines the spacing between fdc chipset registers
1574 defines the offset of register from address. It
1575 depends on which part of the data bus is connected to
1576 the fdc chipset. (default value 0)
1578 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1579 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1582 if CFG_FDC_HW_INIT is defined, then the function
1583 fdc_hw_init() is called at the beginning of the FDC
1584 setup. fdc_hw_init() must be provided by the board
1585 source code. It is used to make hardware dependant
1588 - CFG_IMMR: Physical address of the Internal Memory Mapped
1589 Register; DO NOT CHANGE! (11-4)
1590 [MPC8xx systems only]
1592 - CFG_INIT_RAM_ADDR:
1594 Start address of memory area tha can be used for
1595 initial data and stack; please note that this must be
1596 writable memory that is working WITHOUT special
1597 initialization, i. e. you CANNOT use normal RAM which
1598 will become available only after programming the
1599 memory controller and running certain initialization
1602 U-Boot uses the following memory types:
1603 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1604 - MPC824X: data cache
1605 - PPC4xx: data cache
1607 - CFG_INIT_DATA_OFFSET:
1609 Offset of the initial data structure in the memory
1610 area defined by CFG_INIT_RAM_ADDR. Usually
1611 CFG_INIT_DATA_OFFSET is chosen such that the initial
1612 data is located at the end of the available space
1613 (sometimes written as (CFG_INIT_RAM_END -
1614 CFG_INIT_DATA_SIZE), and the initial stack is just
1615 below that area (growing from (CFG_INIT_RAM_ADDR +
1616 CFG_INIT_DATA_OFFSET) downward.
1619 On the MPC824X (or other systems that use the data
1620 cache for initial memory) the address chosen for
1621 CFG_INIT_RAM_ADDR is basically arbitrary - it must
1622 point to an otherwise UNUSED address space between
1623 the top of RAM and the start of the PCI space.
1625 - CFG_SIUMCR: SIU Module Configuration (11-6)
1627 - CFG_SYPCR: System Protection Control (11-9)
1629 - CFG_TBSCR: Time Base Status and Control (11-26)
1631 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
1633 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
1635 - CFG_SCCR: System Clock and reset Control Register (15-27)
1637 - CFG_OR_TIMING_SDRAM:
1641 periodic timer for refresh
1643 - CFG_DER: Debug Event Register (37-47)
1645 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1646 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1647 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1649 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1651 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1652 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1653 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1654 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1656 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1657 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1658 Machine Mode Register and Memory Periodic Timer
1659 Prescaler definitions (SDRAM timing)
1661 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1662 enable I2C microcode relocation patch (MPC8xx);
1663 define relocation offset in DPRAM [DSP2]
1665 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1666 enable SPI microcode relocation patch (MPC8xx);
1667 define relocation offset in DPRAM [SCC4]
1670 Use OSCM clock mode on MBX8xx board. Be careful,
1671 wrong setting might damage your board. Read
1672 doc/README.MBX before setting this variable!
1674 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
1675 Offset of the bootmode word in DPRAM used by post
1676 (Power On Self Tests). This definition overrides
1677 #define'd default value in commproc.h resp.
1680 Building the Software:
1681 ======================
1683 Building U-Boot has been tested in native PPC environments (on a
1684 PowerBook G3 running LinuxPPC 2000) and in cross environments
1685 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
1688 If you are not using a native PPC environment, it is assumed that you
1689 have the GNU cross compiling tools available in your path and named
1690 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
1691 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
1692 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
1695 CROSS_COMPILE = ppc_4xx-
1698 U-Boot is intended to be simple to build. After installing the
1699 sources you must configure U-Boot for one specific board type. This
1704 where "NAME_config" is the name of one of the existing
1705 configurations; the following names are supported:
1707 ADCIOP_config GTH_config TQM850L_config
1708 ADS860_config IP860_config TQM855L_config
1709 AR405_config IVML24_config TQM860L_config
1710 CANBT_config IVMS8_config WALNUT405_config
1711 CPCI405_config LANTEC_config cogent_common_config
1712 CPCIISER4_config MBX_config cogent_mpc8260_config
1713 CU824_config MBX860T_config cogent_mpc8xx_config
1714 ESTEEM192E_config RPXlite_config hermes_config
1715 ETX094_config RPXsuper_config hymod_config
1716 FADS823_config SM850_config lwmon_config
1717 FADS850SAR_config SPD823TS_config pcu_e_config
1718 FADS860T_config SXNI855T_config rsdproto_config
1719 FPS850L_config Sandpoint8240_config sbc8260_config
1720 GENIETV_config TQM823L_config PIP405_config
1721 GEN860T_config EBONY_config FPS860L_config
1724 Note: for some board special configuration names may exist; check if
1725 additional information is available from the board vendor; for
1726 instance, the TQM8xxL systems run normally at 50 MHz and use a
1727 SCC for 10baseT ethernet; there are also systems with 80 MHz
1728 CPU clock, and an optional Fast Ethernet module is available
1729 for CPU's with FEC. You can select such additional "features"
1730 when chosing the configuration, i. e.
1733 - will configure for a plain TQM860L, i. e. 50MHz, no FEC
1735 make TQM860L_FEC_config
1736 - will configure for a TQM860L at 50MHz with FEC for ethernet
1738 make TQM860L_80MHz_config
1739 - will configure for a TQM860L at 80 MHz, with normal 10baseT
1742 make TQM860L_FEC_80MHz_config
1743 - will configure for a TQM860L at 80 MHz with FEC for ethernet
1745 make TQM823L_LCD_config
1746 - will configure for a TQM823L with U-Boot console on LCD
1748 make TQM823L_LCD_80MHz_config
1749 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD
1755 Finally, type "make all", and you should get some working U-Boot
1756 images ready for downlod to / installation on your system:
1758 - "u-boot.bin" is a raw binary image
1759 - "u-boot" is an image in ELF binary format
1760 - "u-boot.srec" is in Motorola S-Record format
1763 Please be aware that the Makefiles assume you are using GNU make, so
1764 for instance on NetBSD you might need to use "gmake" instead of
1768 If the system board that you have is not listed, then you will need
1769 to port U-Boot to your hardware platform. To do this, follow these
1772 1. Add a new configuration option for your board to the toplevel
1773 "Makefile", using the existing entries as examples.
1774 2. Create a new directory to hold your board specific code. Add any
1776 3. If you're porting U-Boot to a new CPU, then also create a new
1777 directory to hold your CPU specific code. Add any files you need.
1778 4. Run "make config_name" with your new name.
1779 5. Type "make", and you should get a working "u-boot.srec" file
1780 to be installed on your target system.
1781 [Of course, this last step is much harder than it sounds.]
1784 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
1785 ==============================================================
1787 If you have modified U-Boot sources (for instance added a new board
1788 or support for new devices, a new CPU, etc.) you are expected to
1789 provide feedback to the other developers. The feedback normally takes
1790 the form of a "patch", i. e. a context diff against a certain (latest
1791 official or latest in CVS) version of U-Boot sources.
1793 But before you submit such a patch, please verify that your modifi-
1794 cation did not break existing code. At least make sure that *ALL* of
1795 the supported boards compile WITHOUT ANY compiler warnings. To do so,
1796 just run the "MAKEALL" script, which will configure and build U-Boot
1797 for ALL supported system. Be warned, this will take a while. You can
1798 select which (cross) compiler to use py passing a `CROSS_COMPILE'
1799 environment variable to the script, i. e. to use the cross tools from
1800 MontaVista's Hard Hat Linux you can type
1802 CROSS_COMPILE=ppc_8xx- MAKEALL
1804 or to build on a native PowerPC system you can type
1806 CROSS_COMPILE=' ' MAKEALL
1808 See also "U-Boot Porting Guide" below.
1812 Monitor Commands - Overview:
1813 ============================
1815 go - start application at address 'addr'
1816 run - run commands in an environment variable
1817 bootm - boot application image from memory
1818 bootp - boot image via network using BootP/TFTP protocol
1819 tftpboot- boot image via network using TFTP protocol
1820 and env variables "ipaddr" and "serverip"
1821 (and eventually "gatewayip")
1822 rarpboot- boot image via network using RARP/TFTP protocol
1823 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
1824 loads - load S-Record file over serial line
1825 loadb - load binary file over serial line (kermit mode)
1827 mm - memory modify (auto-incrementing)
1828 nm - memory modify (constant address)
1829 mw - memory write (fill)
1831 cmp - memory compare
1832 crc32 - checksum calculation
1833 imd - i2c memory display
1834 imm - i2c memory modify (auto-incrementing)
1835 inm - i2c memory modify (constant address)
1836 imw - i2c memory write (fill)
1837 icrc32 - i2c checksum calculation
1838 iprobe - probe to discover valid I2C chip addresses
1839 iloop - infinite loop on address range
1840 isdram - print SDRAM configuration information
1841 sspi - SPI utility commands
1842 base - print or set address offset
1843 printenv- print environment variables
1844 setenv - set environment variables
1845 saveenv - save environment variables to persistent storage
1846 protect - enable or disable FLASH write protection
1847 erase - erase FLASH memory
1848 flinfo - print FLASH memory information
1849 bdinfo - print Board Info structure
1850 iminfo - print header information for application image
1851 coninfo - print console devices and informations
1852 ide - IDE sub-system
1853 loop - infinite loop on address range
1854 mtest - simple RAM test
1855 icache - enable or disable instruction cache
1856 dcache - enable or disable data cache
1857 reset - Perform RESET of the CPU
1858 echo - echo args to console
1859 version - print monitor version
1860 help - print online help
1861 ? - alias for 'help'
1864 Monitor Commands - Detailed Description:
1865 ========================================
1869 For now: just type "help <command>".
1872 Environment Variables:
1873 ======================
1875 U-Boot supports user configuration using Environment Variables which
1876 can be made persistent by saving to Flash memory.
1878 Environment Variables are set using "setenv", printed using
1879 "printenv", and saved to Flash using "saveenv". Using "setenv"
1880 without a value can be used to delete a variable from the
1881 environment. As long as you don't save the environment you are
1882 working with an in-memory copy. In case the Flash area containing the
1883 environment is erased by accident, a default environment is provided.
1885 Some configuration options can be set using Environment Variables:
1887 baudrate - see CONFIG_BAUDRATE
1889 bootdelay - see CONFIG_BOOTDELAY
1891 bootcmd - see CONFIG_BOOTCOMMAND
1893 bootargs - Boot arguments when booting an RTOS image
1895 bootfile - Name of the image to load with TFTP
1897 autoload - if set to "no" (any string beginning with 'n'),
1898 "bootp" will just load perform a lookup of the
1899 configuration from the BOOTP server, but not try to
1900 load any image using TFTP
1902 autostart - if set to "yes", an image loaded using the "bootp",
1903 "rarpboot", "tftpboot" or "diskboot" commands will
1904 be automatically started (by internally calling
1907 initrd_high - restrict positioning of initrd images:
1908 If this variable is not set, initrd images will be
1909 copied to the highest possible address in RAM; this
1910 is usually what you want since it allows for
1911 maximum initrd size. If for some reason you want to
1912 make sure that the initrd image is loaded below the
1913 CFG_BOOTMAPSZ limit, you can set this environment
1914 variable to a value of "no" or "off" or "0".
1915 Alternatively, you can set it to a maximum upper
1916 address to use (U-Boot will still check that it
1917 does not overwrite the U-Boot stack and data).
1919 For instance, when you have a system with 16 MB
1920 RAM, and want to reseve 4 MB from use by Linux,
1921 you can do this by adding "mem=12M" to the value of
1922 the "bootargs" variable. However, now you must make
1923 sure, that the initrd image is placed in the first
1924 12 MB as well - this can be done with
1926 setenv initrd_high 00c00000
1928 ipaddr - IP address; needed for tftpboot command
1930 loadaddr - Default load address for commands like "bootp",
1931 "rarpboot", "tftpboot" or "diskboot"
1933 loads_echo - see CONFIG_LOADS_ECHO
1935 serverip - TFTP server IP address; needed for tftpboot command
1937 bootretry - see CONFIG_BOOT_RETRY_TIME
1939 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
1941 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
1944 The following environment variables may be used and automatically
1945 updated by the network boot commands ("bootp" and "rarpboot"),
1946 depending the information provided by your boot server:
1948 bootfile - see above
1949 dnsip - IP address of your Domain Name Server
1950 gatewayip - IP address of the Gateway (Router) to use
1951 hostname - Target hostname
1953 netmask - Subnet Mask
1954 rootpath - Pathname of the root filesystem on the NFS server
1955 serverip - see above
1958 There are two special Environment Variables:
1960 serial# - contains hardware identification information such
1961 as type string and/or serial number
1962 ethaddr - Ethernet address
1964 These variables can be set only once (usually during manufacturing of
1965 the board). U-Boot refuses to delete or overwrite these variables
1966 once they have been set once.
1969 Please note that changes to some configuration parameters may take
1970 only effect after the next boot (yes, that's just like Windoze :-).
1973 Note for Redundant Ethernet Interfaces:
1974 =======================================
1976 Some boards come with redundand ethernet interfaces; U-Boot supports
1977 such configurations and is capable of automatic selection of a
1978 "working" interface when needed. MAC assignemnt works as follows:
1980 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
1981 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
1982 "eth1addr" (=>eth1), "eth2addr", ...
1984 If the network interface stores some valid MAC address (for instance
1985 in SROM), this is used as default address if there is NO correspon-
1986 ding setting in the environment; if the corresponding environment
1987 variable is set, this overrides the settings in the card; that means:
1989 o If the SROM has a valid MAC address, and there is no address in the
1990 environment, the SROM's address is used.
1992 o If there is no valid address in the SROM, and a definition in the
1993 environment exists, then the value from the environment variable is
1996 o If both the SROM and the environment contain a MAC address, and
1997 both addresses are the same, this MAC address is used.
1999 o If both the SROM and the environment contain a MAC address, and the
2000 addresses differ, the value from the environment is used and a
2003 o If neither SROM nor the environment contain a MAC address, an error
2011 The "boot" commands of this monitor operate on "image" files which
2012 can be basicly anything, preceeded by a special header; see the
2013 definitions in include/image.h for details; basicly, the header
2014 defines the following image properties:
2016 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2017 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2019 Currently supported: Linux, NetBSD, VxWorks, QNX).
2020 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2021 IA64, MIPS, MIPS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2022 Currently supported: PowerPC).
2023 * Compression Type (Provisions for uncompressed, gzip, bzip2;
2024 Currently supported: uncompressed, gzip).
2030 The header is marked by a special Magic Number, and both the header
2031 and the data portions of the image are secured against corruption by
2038 Although U-Boot should support any OS or standalone application
2039 easily, Linux has always been in the focus during the design of
2042 U-Boot includes many features that so far have been part of some
2043 special "boot loader" code within the Linux kernel. Also, any
2044 "initrd" images to be used are no longer part of one big Linux image;
2045 instead, kernel and "initrd" are separate images. This implementation
2046 serves serveral purposes:
2048 - the same features can be used for other OS or standalone
2049 applications (for instance: using compressed images to reduce the
2050 Flash memory footprint)
2052 - it becomes much easier to port new Linux kernel versions because
2053 lots of low-level, hardware dependend stuff are done by U-Boot
2055 - the same Linux kernel image can now be used with different "initrd"
2056 images; of course this also means that different kernel images can
2057 be run with the same "initrd". This makes testing easier (you don't
2058 have to build a new "zImage.initrd" Linux image when you just
2059 change a file in your "initrd"). Also, a field-upgrade of the
2060 software is easier now.
2066 Porting Linux to U-Boot based systems:
2067 ---------------------------------------
2069 U-Boot cannot save you from doing all the necessary modifications to
2070 configure the Linux device drivers for use with your target hardware
2071 (no, we don't intend to provide a full virtual machine interface to
2074 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2076 Just make sure your machine specific header file (for instance
2077 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2078 Information structure as we define in include/u-boot.h, and make
2079 sure that your definition of IMAP_ADDR uses the same value as your
2080 U-Boot configuration in CFG_IMMR.
2083 Configuring the Linux kernel:
2084 -----------------------------
2086 No specific requirements for U-Boot. Make sure you have some root
2087 device (initial ramdisk, NFS) for your target system.
2090 Building a Linux Image:
2091 -----------------------
2093 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2094 not used. If you use recent kernel source, a new build target
2095 "uImage" will exist which automatically builds an image usable by
2096 U-Boot. Most older kernels also have support for a "pImage" target,
2097 which was introduced for our predecessor project PPCBoot and uses a
2098 100% compatible format.
2107 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2108 encapsulate a compressed Linux kernel image with header information,
2109 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2111 * build a standard "vmlinux" kernel image (in ELF binary format):
2113 * convert the kernel into a raw binary image:
2115 ${CROSS_COMPILE}-objcopy -O binary \
2116 -R .note -R .comment \
2117 -S vmlinux linux.bin
2119 * compress the binary image:
2123 * package compressed binary image for U-Boot:
2125 mkimage -A ppc -O linux -T kernel -C gzip \
2126 -a 0 -e 0 -n "Linux Kernel Image" \
2127 -d linux.bin.gz uImage
2130 The "mkimage" tool can also be used to create ramdisk images for use
2131 with U-Boot, either separated from the Linux kernel image, or
2132 combined into one file. "mkimage" encapsulates the images with a 64
2133 byte header containing information about target architecture,
2134 operating system, image type, compression method, entry points, time
2135 stamp, CRC32 checksums, etc.
2137 "mkimage" can be called in two ways: to verify existing images and
2138 print the header information, or to build new images.
2140 In the first form (with "-l" option) mkimage lists the information
2141 contained in the header of an existing U-Boot image; this includes
2142 checksum verification:
2144 tools/mkimage -l image
2145 -l ==> list image header information
2147 The second form (with "-d" option) is used to build a U-Boot image
2148 from a "data file" which is used as image payload:
2150 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2151 -n name -d data_file image
2152 -A ==> set architecture to 'arch'
2153 -O ==> set operating system to 'os'
2154 -T ==> set image type to 'type'
2155 -C ==> set compression type 'comp'
2156 -a ==> set load address to 'addr' (hex)
2157 -e ==> set entry point to 'ep' (hex)
2158 -n ==> set image name to 'name'
2159 -d ==> use image data from 'datafile'
2161 Right now, all Linux kernels use the same load address (0x00000000),
2162 but the entry point address depends on the kernel version:
2164 - 2.2.x kernels have the entry point at 0x0000000C,
2165 - 2.3.x and later kernels have the entry point at 0x00000000.
2167 So a typical call to build a U-Boot image would read:
2169 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2170 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2171 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2172 > examples/uImage.TQM850L
2173 Image Name: 2.4.4 kernel for TQM850L
2174 Created: Wed Jul 19 02:34:59 2000
2175 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2176 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2177 Load Address: 0x00000000
2178 Entry Point: 0x00000000
2180 To verify the contents of the image (or check for corruption):
2182 -> tools/mkimage -l examples/uImage.TQM850L
2183 Image Name: 2.4.4 kernel for TQM850L
2184 Created: Wed Jul 19 02:34:59 2000
2185 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2186 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2187 Load Address: 0x00000000
2188 Entry Point: 0x00000000
2190 NOTE: for embedded systems where boot time is critical you can trade
2191 speed for memory and install an UNCOMPRESSED image instead: this
2192 needs more space in Flash, but boots much faster since it does not
2193 need to be uncompressed:
2195 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2196 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2197 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2198 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2199 > examples/uImage.TQM850L-uncompressed
2200 Image Name: 2.4.4 kernel for TQM850L
2201 Created: Wed Jul 19 02:34:59 2000
2202 Image Type: PowerPC Linux Kernel Image (uncompressed)
2203 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2204 Load Address: 0x00000000
2205 Entry Point: 0x00000000
2208 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2209 when your kernel is intended to use an initial ramdisk:
2211 -> tools/mkimage -n 'Simple Ramdisk Image' \
2212 > -A ppc -O linux -T ramdisk -C gzip \
2213 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2214 Image Name: Simple Ramdisk Image
2215 Created: Wed Jan 12 14:01:50 2000
2216 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2217 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2218 Load Address: 0x00000000
2219 Entry Point: 0x00000000
2222 Installing a Linux Image:
2223 -------------------------
2225 To downloading a U-Boot image over the serial (console) interface,
2226 you must convert the image to S-Record format:
2228 objcopy -I binary -O srec examples/image examples/image.srec
2230 The 'objcopy' does not understand the information in the U-Boot
2231 image header, so the resulting S-Record file will be relative to
2232 address 0x00000000. To load it to a given address, you need to
2233 specify the target address as 'offset' parameter with the 'loads'
2236 Example: install the image to address 0x40100000 (which on the
2237 TQM8xxL is in the first Flash bank):
2239 => erase 40100000 401FFFFF
2245 ## Ready for S-Record download ...
2246 ~>examples/image.srec
2247 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2249 15989 15990 15991 15992
2250 [file transfer complete]
2252 ## Start Addr = 0x00000000
2255 You can check the success of the download using the 'iminfo' command;
2256 this includes a checksum verification so you can be sure no data
2257 corruption happened:
2261 ## Checking Image at 40100000 ...
2262 Image Name: 2.2.13 for initrd on TQM850L
2263 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2264 Data Size: 335725 Bytes = 327 kB = 0 MB
2265 Load Address: 00000000
2266 Entry Point: 0000000c
2267 Verifying Checksum ... OK
2274 The "bootm" command is used to boot an application that is stored in
2275 memory (RAM or Flash). In case of a Linux kernel image, the contents
2276 of the "bootargs" environment variable is passed to the kernel as
2277 parameters. You can check and modify this variable using the
2278 "printenv" and "setenv" commands:
2281 => printenv bootargs
2282 bootargs=root=/dev/ram
2284 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2286 => printenv bootargs
2287 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2290 ## Booting Linux kernel at 40020000 ...
2291 Image Name: 2.2.13 for NFS on TQM850L
2292 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2293 Data Size: 381681 Bytes = 372 kB = 0 MB
2294 Load Address: 00000000
2295 Entry Point: 0000000c
2296 Verifying Checksum ... OK
2297 Uncompressing Kernel Image ... OK
2298 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
2299 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2300 time_init: decrementer frequency = 187500000/60
2301 Calibrating delay loop... 49.77 BogoMIPS
2302 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2305 If you want to boot a Linux kernel with initial ram disk, you pass
2306 the memory addreses of both the kernel and the initrd image (PPBCOOT
2307 format!) to the "bootm" command:
2309 => imi 40100000 40200000
2311 ## Checking Image at 40100000 ...
2312 Image Name: 2.2.13 for initrd on TQM850L
2313 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2314 Data Size: 335725 Bytes = 327 kB = 0 MB
2315 Load Address: 00000000
2316 Entry Point: 0000000c
2317 Verifying Checksum ... OK
2319 ## Checking Image at 40200000 ...
2320 Image Name: Simple Ramdisk Image
2321 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2322 Data Size: 566530 Bytes = 553 kB = 0 MB
2323 Load Address: 00000000
2324 Entry Point: 00000000
2325 Verifying Checksum ... OK
2327 => bootm 40100000 40200000
2328 ## Booting Linux kernel at 40100000 ...
2329 Image Name: 2.2.13 for initrd on TQM850L
2330 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2331 Data Size: 335725 Bytes = 327 kB = 0 MB
2332 Load Address: 00000000
2333 Entry Point: 0000000c
2334 Verifying Checksum ... OK
2335 Uncompressing Kernel Image ... OK
2336 ## Loading RAMDisk Image at 40200000 ...
2337 Image Name: Simple Ramdisk Image
2338 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2339 Data Size: 566530 Bytes = 553 kB = 0 MB
2340 Load Address: 00000000
2341 Entry Point: 00000000
2342 Verifying Checksum ... OK
2343 Loading Ramdisk ... OK
2344 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
2345 Boot arguments: root=/dev/ram
2346 time_init: decrementer frequency = 187500000/60
2347 Calibrating delay loop... 49.77 BogoMIPS
2349 RAMDISK: Compressed image found at block 0
2350 VFS: Mounted root (ext2 filesystem).
2354 More About U-Boot Image Types:
2355 ------------------------------
2357 U-Boot supports the following image types:
2359 "Standalone Programs" are directly runnable in the environment
2360 provided by U-Boot; it is expected that (if they behave
2361 well) you can continue to work in U-Boot after return from
2362 the Standalone Program.
2363 "OS Kernel Images" are usually images of some Embedded OS which
2364 will take over control completely. Usually these programs
2365 will install their own set of exception handlers, device
2366 drivers, set up the MMU, etc. - this means, that you cannot
2367 expect to re-enter U-Boot except by resetting the CPU.
2368 "RAMDisk Images" are more or less just data blocks, and their
2369 parameters (address, size) are passed to an OS kernel that is
2371 "Multi-File Images" contain several images, typically an OS
2372 (Linux) kernel image and one or more data images like
2373 RAMDisks. This construct is useful for instance when you want
2374 to boot over the network using BOOTP etc., where the boot
2375 server provides just a single image file, but you want to get
2376 for instance an OS kernel and a RAMDisk image.
2378 "Multi-File Images" start with a list of image sizes, each
2379 image size (in bytes) specified by an "uint32_t" in network
2380 byte order. This list is terminated by an "(uint32_t)0".
2381 Immediately after the terminating 0 follow the images, one by
2382 one, all aligned on "uint32_t" boundaries (size rounded up to
2383 a multiple of 4 bytes).
2385 "Firmware Images" are binary images containing firmware (like
2386 U-Boot or FPGA images) which usually will be programmed to
2389 "Script files" are command sequences that will be executed by
2390 U-Boot's command interpreter; this feature is especially
2391 useful when you configure U-Boot to use a real shell (hush)
2392 as command interpreter.
2398 One of the features of U-Boot is that you can dynamically load and
2399 run "standalone" applications, which can use some resources of
2400 U-Boot like console I/O functions or interrupt services.
2402 Two simple examples are included with the sources:
2407 'examples/hello_world.c' contains a small "Hello World" Demo
2408 application; it is automatically compiled when you build U-Boot.
2409 It's configured to run at address 0x00040004, so you can play with it
2413 ## Ready for S-Record download ...
2414 ~>examples/hello_world.srec
2415 1 2 3 4 5 6 7 8 9 10 11 ...
2416 [file transfer complete]
2418 ## Start Addr = 0x00040004
2420 => go 40004 Hello World! This is a test.
2421 ## Starting application at 0x00040004 ...
2432 Hit any key to exit ...
2434 ## Application terminated, rc = 0x0
2436 Another example, which demonstrates how to register a CPM interrupt
2437 handler with the U-Boot code, can be found in 'examples/timer.c'.
2438 Here, a CPM timer is set up to generate an interrupt every second.
2439 The interrupt service routine is trivial, just printing a '.'
2440 character, but this is just a demo program. The application can be
2441 controlled by the following keys:
2443 ? - print current values og the CPM Timer registers
2444 b - enable interrupts and start timer
2445 e - stop timer and disable interrupts
2446 q - quit application
2449 ## Ready for S-Record download ...
2450 ~>examples/timer.srec
2451 1 2 3 4 5 6 7 8 9 10 11 ...
2452 [file transfer complete]
2454 ## Start Addr = 0x00040004
2457 ## Starting application at 0x00040004 ...
2460 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2463 [q, b, e, ?] Set interval 1000000 us
2466 [q, b, e, ?] ........
2467 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2470 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2473 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2476 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2478 [q, b, e, ?] ...Stopping timer
2480 [q, b, e, ?] ## Application terminated, rc = 0x0
2486 Starting at version 0.9.2, U-Boot supports NetBSD both as host
2487 (build U-Boot) and target system (boots NetBSD/mpc8xx).
2489 Building requires a cross environment; it is known to work on
2490 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2491 need gmake since the Makefiles are not compatible with BSD make).
2492 Note that the cross-powerpc package does not install include files;
2493 attempting to build U-Boot will fail because <machine/ansi.h> is
2494 missing. This file has to be installed and patched manually:
2496 # cd /usr/pkg/cross/powerpc-netbsd/include
2498 # ln -s powerpc machine
2499 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2500 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
2502 Native builds *don't* work due to incompatibilities between native
2503 and U-Boot include files.
2505 Booting assumes that (the first part of) the image booted is a
2506 stage-2 loader which in turn loads and then invokes the kernel
2507 proper. Loader sources will eventually appear in the NetBSD source
2508 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2509 meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2513 Implementation Internals:
2514 =========================
2516 The following is not intended to be a complete description of every
2517 implementation detail. However, it should help to understand the
2518 inner workings of U-Boot and make it easier to port it to custom
2522 Initial Stack, Global Data:
2523 ---------------------------
2525 The implementation of U-Boot is complicated by the fact that U-Boot
2526 starts running out of ROM (flash memory), usually without access to
2527 system RAM (because the memory controller is not initialized yet).
2528 This means that we don't have writable Data or BSS segments, and BSS
2529 is not initialized as zero. To be able to get a C environment working
2530 at all, we have to allocate at least a minimal stack. Implementation
2531 options for this are defined and restricted by the CPU used: Some CPU
2532 models provide on-chip memory (like the IMMR area on MPC8xx and
2533 MPC826x processors), on others (parts of) the data cache can be
2534 locked as (mis-) used as memory, etc.
2536 Chris Hallinan posted a good summy of these issues to the
2537 u-boot-users mailing list:
2539 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2540 From: "Chris Hallinan" <clh@net1plus.com>
2541 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2544 Correct me if I'm wrong, folks, but the way I understand it
2545 is this: Using DCACHE as initial RAM for Stack, etc, does not
2546 require any physical RAM backing up the cache. The cleverness
2547 is that the cache is being used as a temporary supply of
2548 necessary storage before the SDRAM controller is setup. It's
2549 beyond the scope of this list to expain the details, but you
2550 can see how this works by studying the cache architecture and
2551 operation in the architecture and processor-specific manuals.
2553 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2554 is another option for the system designer to use as an
2555 initial stack/ram area prior to SDRAM being available. Either
2556 option should work for you. Using CS 4 should be fine if your
2557 board designers haven't used it for something that would
2558 cause you grief during the initial boot! It is frequently not
2561 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
2562 with your processor/board/system design. The default value
2563 you will find in any recent u-boot distribution in
2564 Walnut405.h should work for you. I'd set it to a value larger
2565 than your SDRAM module. If you have a 64MB SDRAM module, set
2566 it above 400_0000. Just make sure your board has no resources
2567 that are supposed to respond to that address! That code in
2568 start.S has been around a while and should work as is when
2569 you get the config right.
2574 It is essential to remember this, since it has some impact on the C
2575 code for the initialization procedures:
2577 * Initialized global data (data segment) is read-only. Do not attempt
2580 * Do not use any unitialized global data (or implicitely initialized
2581 as zero data - BSS segment) at all - this is undefined, initiali-
2582 zation is performed later (when relocationg to RAM).
2584 * Stack space is very limited. Avoid big data buffers or things like
2587 Having only the stack as writable memory limits means we cannot use
2588 normal global data to share information beween the code. But it
2589 turned out that the implementation of U-Boot can be greatly
2590 simplified by making a global data structure (gd_t) available to all
2591 functions. We could pass a pointer to this data as argument to _all_
2592 functions, but this would bloat the code. Instead we use a feature of
2593 the GCC compiler (Global Register Variables) to share the data: we
2594 place a pointer (gd) to the global data into a register which we
2595 reserve for this purpose.
2597 When chosing a register for such a purpose we are restricted by the
2598 relevant (E)ABI specifications for the current architecture, and by
2599 GCC's implementation.
2601 For PowerPC, the following registers have specific use:
2604 R3-R4: parameter passing and return values
2605 R5-R10: parameter passing
2606 R13: small data area pointer
2610 (U-Boot also uses R14 as internal GOT pointer.)
2612 ==> U-Boot will use R29 to hold a pointer to the global data
2614 Note: on PPC, we could use a static initializer (since the
2615 address of the global data structure is known at compile time),
2616 but it turned out that reserving a register results in somewhat
2617 smaller code - although the code savings are not that big (on
2618 average for all boards 752 bytes for the whole U-Boot image,
2619 624 text + 127 data).
2621 On ARM, the following registers are used:
2623 R0: function argument word/integer result
2624 R1-R3: function argument word
2626 R10: stack limit (used only if stack checking if enabled)
2627 R11: argument (frame) pointer
2628 R12: temporary workspace
2631 R15: program counter
2633 ==> U-Boot will use R8 to hold a pointer to the global data
2640 U-Boot runs in system state and uses physical addresses, i.e. the
2641 MMU is not used either for address mapping nor for memory protection.
2643 The available memory is mapped to fixed addresses using the memory
2644 controller. In this process, a contiguous block is formed for each
2645 memory type (Flash, SDRAM, SRAM), even when it consists of several
2646 physical memory banks.
2648 U-Boot is installed in the first 128 kB of the first Flash bank (on
2649 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
2650 booting and sizing and initializing DRAM, the code relocates itself
2651 to the upper end of DRAM. Immediately below the U-Boot code some
2652 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
2653 configuration setting]. Below that, a structure with global Board
2654 Info data is placed, followed by the stack (growing downward).
2656 Additionally, some exception handler code is copied to the low 8 kB
2657 of DRAM (0x00000000 ... 0x00001FFF).
2659 So a typical memory configuration with 16 MB of DRAM could look like
2662 0x0000 0000 Exception Vector code
2665 0x0000 2000 Free for Application Use
2671 0x00FB FF20 Monitor Stack (Growing downward)
2672 0x00FB FFAC Board Info Data and permanent copy of global data
2673 0x00FC 0000 Malloc Arena
2676 0x00FE 0000 RAM Copy of Monitor Code
2677 ... eventually: LCD or video framebuffer
2678 ... eventually: pRAM (Protected RAM - unchanged by reset)
2679 0x00FF FFFF [End of RAM]
2682 System Initialization:
2683 ----------------------
2685 In the reset configuration, U-Boot starts at the reset entry point
2686 (on most PowerPC systens at address 0x00000100). Because of the reset
2687 configuration for CS0# this is a mirror of the onboard Flash memory.
2688 To be able to re-map memory U-Boot then jumps to it's link address.
2689 To be able to implement the initialization code in C, a (small!)
2690 initial stack is set up in the internal Dual Ported RAM (in case CPUs
2691 which provide such a feature like MPC8xx or MPC8260), or in a locked
2692 part of the data cache. After that, U-Boot initializes the CPU core,
2693 the caches and the SIU.
2695 Next, all (potentially) available memory banks are mapped using a
2696 preliminary mapping. For example, we put them on 512 MB boundaries
2697 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
2698 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
2699 programmed for SDRAM access. Using the temporary configuration, a
2700 simple memory test is run that determines the size of the SDRAM
2703 When there is more than one SDRAM bank, and the banks are of
2704 different size, the larger is mapped first. For equal size, the first
2705 bank (CS2#) is mapped first. The first mapping is always for address
2706 0x00000000, with any additional banks following immediately to create
2707 contiguous memory starting from 0.
2709 Then, the monitor installs itself at the upper end of the SDRAM area
2710 and allocates memory for use by malloc() and for the global Board
2711 Info data; also, the exception vector code is copied to the low RAM
2712 pages, and the final stack is set up.
2714 Only after this relocation will you have a "normal" C environment;
2715 until that you are restricted in several ways, mostly because you are
2716 running from ROM, and because the code will have to be relocated to a
2720 U-Boot Porting Guide:
2721 ----------------------
2723 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
2727 int main (int argc, char *argv[])
2729 sighandler_t no_more_time;
2731 signal (SIGALRM, no_more_time);
2732 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
2734 if (available_money > available_manpower) {
2735 pay consultant to port U-Boot;
2739 Download latest U-Boot source;
2741 Subscribe to u-boot-users mailing list;
2744 email ("Hi, I am new to U-Boot, how do I get started?");
2748 Read the README file in the top level directory;
2749 Read http://www.denx.de/re/DPLG.html
2750 Read the source, Luke;
2753 if (available_money > toLocalCurrency ($2500)) {
2756 Add a lot of aggravation and time;
2759 Create your own board support subdirectory;
2761 Create your own board config file;
2765 Add / modify source code;
2769 email ("Hi, I am having problems...");
2771 Send patch file to Wolfgang;
2776 void no_more_time (int sig)
2786 All contributions to U-Boot should conform to the Linux kernel
2787 coding style; see the file "Documentation/CodingStyle" in your Linux
2788 kernel source directory.
2790 Please note that U-Boot is implemented in C (and to some small parts
2791 in Assembler); no C++ is used, so please do not use C++ style
2792 comments (//) in your code.
2794 Submissions which do not conform to the standards may be returned
2795 with a request to reformat the changes.
2801 Since the number of patches for U-Boot is growing, we need to
2802 establish some rules. Submissions which do not conform to these rules
2803 may be rejected, even when they contain important and valuable stuff.
2806 When you send a patch, please include the following information with
2809 * For bug fixes: a description of the bug and how your patch fixes
2810 this bug. Please try to include a way of demonstrating that the
2811 patch actually fixes something.
2813 * For new features: a description of the feature and your
2816 * A CHANGELOG entry as plaintext (separate from the patch)
2818 * For major contributions, your entry to the CREDITS file
2820 * When you add support for a new board, don't forget to add this
2821 board to the MAKEALL script, too.
2823 * If your patch adds new configuration options, don't forget to
2824 document these in the README file.
2826 * The patch itself. If you are accessing the CVS repository use "cvs
2827 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
2828 version of diff does not support these options, then get the latest
2829 version of GNU diff.
2831 We accept patches as plain text, MIME attachments or as uuencoded
2836 * Before sending the patch, run the MAKEALL script on your patched
2837 source tree and make sure that no errors or warnings are reported
2838 for any of the boards.
2840 * Keep your modifications to the necessary minimum: A patch
2841 containing several unrelated changes or arbitrary reformats will be
2842 returned with a request to re-formatting / split it.
2844 * If you modify existing code, make sure that your new code does not
2845 add to the memory footprint of the code ;-) Small is beautiful!
2846 When adding new features, these should compile conditionally only
2847 (using #ifdef), and the resulting code with the new feature
2848 disabled must not need more memory than the old code without your
projects / karo-tx-uboot.git / blob