1# 2# (C) Copyright 2000 - 2002 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 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. 12# 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. 17# 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, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC and ARM processors, which can be 29installed in a boot ROM and used to initialize and test the hardware 30or to download and run application code. 31 32The development of U-Boot is closely related to Linux: some parts of 33the source code originate in the Linux source tree, we have some 34header files in common, and special provision has been made to 35support booting of Linux images. 36 37Some attention has been paid to make this software easily 38configurable and extendable. For instance, all monitor commands are 39implemented with the same call interface, so that it's very easy to 40add new commands. Also, instead of permanently adding rarely used 41code (for instance hardware test utilities) to the monitor, you can 42load and run it dynamically. 43 44 45Status: 46======= 47 48In general, all boards for which a configuration option exists in the 49Makefile have been tested to some extent and can be considered 50"working". In fact, many of them are used in production systems. 51 52In case of problems see the CHANGELOG and CREDITS files to find out 53who contributed the specific port. 54 55 56Where to get help: 57================== 58 59In case you have questions about, problems with or contributions for 60U-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 62previous traffic on the mailing list - please search the archive 63before asking FAQ's. Please see 64http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 65 66 67Where we come from: 68=================== 69 70- start from 8xxrom sources 71- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 72- clean up code 73- make it easier to add custom boards 74- make it possible to add other [PowerPC] CPUs 75- extend functions, especially: 76 * Provide extended interface to Linux boot loader 77 * S-Record download 78 * network boot 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) 83 84 85Names and Spelling: 86=================== 87 88The "official" name of this project is "Das U-Boot". The spelling 89"U-Boot" shall be used in all written text (documentation, comments 90in source files etc.). Example: 91 92 This is the README file for the U-Boot project. 93 94File names etc. shall be based on the string "u-boot". Examples: 95 96 include/asm-ppc/u-boot.h 97 98 #include <asm/u-boot.h> 99 100Variable names, preprocessor constants etc. shall be either based on 101the string "u_boot" or on "U_BOOT". Example: 102 103 U_BOOT_VERSION u_boot_logo 104 IH_OS_U_BOOT u_boot_hush_start 105 106 107Versioning: 108=========== 109 110U-Boot uses a 3 level version number containing a version, a 111sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 112sub-version "34", and patchlevel "4". 113 114The patchlevel is used to indicate certain stages of development 115between released versions, i. e. officially released versions of 116U-Boot will always have a patchlevel of "0". 117 118 119Directory Hierarchy: 120==================== 121 122- 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. 141 142- cpu/74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs 143- cpu/mpc5xx Files specific to Motorola MPC5xx CPUs 144- cpu/mpc8xx Files specific to Motorola MPC8xx CPUs 145- cpu/mpc824x Files specific to Motorola MPC824x CPUs 146- cpu/mpc8260 Files specific to Motorola MPC8260 CPU 147- cpu/ppc4xx Files specific to IBM 4xx CPUs 148 149- board/LEOX/ Files specific to boards manufactured by The LEOX team 150- board/LEOX/elpt860 Files specific to ELPT860 boards 151- board/RPXClassic 152 Files specific to RPXClassic boards 153- board/RPXlite Files specific to RPXlite boards 154- board/c2mon Files specific to c2mon boards 155- board/cmi Files specific to cmi boards 156- board/cogent Files specific to Cogent boards 157 (need further configuration) 158 Files specific to CPCIISER4 boards 159- board/cpu86 Files specific to CPU86 boards 160- board/cray/ Files specific to boards manufactured by Cray 161- board/cray/L1 Files specific to L1 boards 162- board/cu824 Files specific to CU824 boards 163- board/ebony Files specific to IBM Ebony board 164- board/eric Files specific to ERIC boards 165- board/esd/ Files specific to boards manufactured by ESD 166- board/esd/adciop Files specific to ADCIOP boards 167- board/esd/ar405 Files specific to AR405 boards 168- board/esd/canbt Files specific to CANBT boards 169- board/esd/cpci405 Files specific to CPCI405 boards 170- board/esd/cpciiser4 Files specific to CPCIISER4 boards 171- board/esd/common Common files for ESD boards 172- board/esd/dasa_sim Files specific to DASA_SIM boards 173- board/esd/du405 Files specific to DU405 boards 174- board/esd/ocrtc Files specific to OCRTC boards 175- board/esd/pci405 Files specific to PCI405 boards 176- board/esteem192e 177 Files specific to ESTEEM192E boards 178- board/etx094 Files specific to ETX_094 boards 179- board/evb64260 180 Files specific to EVB64260 boards 181- board/fads Files specific to FADS boards 182- board/flagadm Files specific to FLAGADM boards 183- board/gen860t Files specific to GEN860T and GEN860T_SC boards 184- board/genietv Files specific to GENIETV boards 185- board/gth Files specific to GTH boards 186- board/hermes Files specific to HERMES boards 187- board/hymod Files specific to HYMOD boards 188- board/icu862 Files specific to ICU862 boards 189- board/ip860 Files specific to IP860 boards 190- board/iphase4539 191 Files specific to Interphase4539 boards 192- board/ivm Files specific to IVMS8/IVML24 boards 193- board/lantec Files specific to LANTEC boards 194- board/lwmon Files specific to LWMON boards 195- board/mbx8xx Files specific to MBX boards 196- board/mpc8260ads 197 Files specific to MMPC8260ADS boards 198- board/mpl/ Files specific to boards manufactured by MPL 199- board/mpl/common Common files for MPL boards 200- board/mpl/pip405 Files specific to PIP405 boards 201- board/mpl/mip405 Files specific to MIP405 boards 202- board/musenki Files specific to MUSEKNI boards 203- board/mvs1 Files specific to MVS1 boards 204- board/nx823 Files specific to NX823 boards 205- board/oxc Files specific to OXC boards 206- board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards 207- board/pm826 Files specific to PM826 boards 208- board/ppmc8260 209 Files specific to PPMC8260 boards 210- board/rpxsuper 211 Files specific to RPXsuper boards 212- board/rsdproto 213 Files specific to RSDproto boards 214- board/sandpoint 215 Files specific to Sandpoint boards 216- board/sbc8260 Files specific to SBC8260 boards 217- board/sacsng Files specific to SACSng boards 218- board/siemens Files specific to boards manufactured by Siemens AG 219- board/siemens/CCM Files specific to CCM boards 220- board/siemens/IAD210 Files specific to IAD210 boards 221- board/siemens/SCM Files specific to SCM boards 222- board/siemens/pcu_e Files specific to PCU_E boards 223- board/sixnet Files specific to SIXNET boards 224- board/spd8xx Files specific to SPD8xxTS boards 225- board/tqm8260 Files specific to TQM8260 boards 226- board/tqm8xx Files specific to TQM8xxL boards 227- board/w7o Files specific to W7O boards 228- board/walnut405 229 Files specific to Walnut405 boards 230- board/westel/ Files specific to boards manufactured by Westel Wireless 231- board/westel/amx860 Files specific to AMX860 boards 232- board/utx8245 Files specific to UTX8245 boards 233 234Software Configuration: 235======================= 236 237Configuration is usually done using C preprocessor defines; the 238rationale behind that is to avoid dead code whenever possible. 239 240There are two classes of configuration variables: 241 242* Configuration _OPTIONS_: 243 These are selectable by the user and have names beginning with 244 "CONFIG_". 245 246* Configuration _SETTINGS_: 247 These depend on the hardware etc. and should not be meddled with if 248 you don't know what you're doing; they have names beginning with 249 "CFG_". 250 251Later we will add a configuration tool - probably similar to or even 252identical to what's used for the Linux kernel. Right now, we have to 253do the configuration by hand, which means creating some symbolic 254links and editing some configuration files. We use the TQM8xxL boards 255as an example here. 256 257 258Selection of Processor Architecture and Board Type: 259--------------------------------------------------- 260 261For all supported boards there are ready-to-use default 262configurations available; just type "make <board_name>_config". 263 264Example: For a TQM823L module type: 265 266 cd u-boot 267 make TQM823L_config 268 269For the Cogent platform, you need to specify the cpu type as well; 270e.g. "make cogent_mpc8xx_config". And also configure the cogent 271directory according to the instructions in cogent/README. 272 273 274Configuration Options: 275---------------------- 276 277Configuration depends on the combination of board and CPU type; all 278such information is kept in a configuration file 279"include/configs/<board_name>.h". 280 281Example: For a TQM823L module, all configuration settings are in 282"include/configs/TQM823L.h". 283 284 285Many of the options are named exactly as the corresponding Linux 286kernel configuration options. The intention is to make it easier to 287build a config tool - later. 288 289 290The following options need to be configured: 291 292- CPU Type: Define exactly one of 293 294 PowerPC based CPUs: 295 ------------------- 296 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860 297 or CONFIG_MPC5xx 298 or CONFIG_MPC824X, CONFIG_MPC8260 299 or CONFIG_IOP480 300 or CONFIG_405GP 301 or CONFIG_440 302 or CONFIG_MPC74xx 303 304 ARM based CPUs: 305 --------------- 306 CONFIG_SA1110 307 CONFIG_ARM7 308 CONFIG_PXA250 309 310 311- Board Type: Define exactly one of 312 313 PowerPC based boards: 314 --------------------- 315 316 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper, 317 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850, 318 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS, 319 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T, 320 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240, 321 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245, 322 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L, 323 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L, 324 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L, 325 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L, 326 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260, 327 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech, 328 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245, 329 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC, 330 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG, 331 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405, 332 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA, 333 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon, 334 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260, 335 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx, 336 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260, 337 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260, 338 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes, 339 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod, 340 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon, 341 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e, 342 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260, 343 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto, 344 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260, 345 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L, 346 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI, 347 CONFIG_NETVIA 348 349 ARM based boards: 350 ----------------- 351 352 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312, 353 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK, 354 CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410, 355 CONFIG_TRAB 356 357 358- CPU Module Type: (if CONFIG_COGENT is defined) 359 Define exactly one of 360 CONFIG_CMA286_60_OLD 361--- FIXME --- not tested yet: 362 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 363 CONFIG_CMA287_23, CONFIG_CMA287_50 364 365- Motherboard Type: (if CONFIG_COGENT is defined) 366 Define exactly one of 367 CONFIG_CMA101, CONFIG_CMA102 368 369- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 370 Define one or more of 371 CONFIG_CMA302 372 373- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 374 Define one or more of 375 CONFIG_LCD_HEARTBEAT - update a character position on 376 the lcd display every second with 377 a "rotator" |\-/|\-/ 378 379- MPC824X Family Member (if CONFIG_MPC824X is defined) 380 Define exactly one of 381 CONFIG_MPC8240, CONFIG_MPC8245 382 383- 8xx CPU Options: (if using an 8xx cpu) 384 Define one or more of 385 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() can not work e.g. 386 no 32KHz reference PIT/RTC clock 387 388- Clock Interface: 389 CONFIG_CLOCKS_IN_MHZ 390 391 U-Boot stores all clock information in Hz 392 internally. For binary compatibility with older Linux 393 kernels (which expect the clocks passed in the 394 bd_info data to be in MHz) the environment variable 395 "clocks_in_mhz" can be defined so that U-Boot 396 converts clock data to MHZ before passing it to the 397 Linux kernel. 398 399 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 400 "clocks_in_mhz=1" is automatically included in the 401 default environment. 402 403- Console Interface: 404 Depending on board, define exactly one serial port 405 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 406 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 407 console by defining CONFIG_8xx_CONS_NONE 408 409 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 410 port routines must be defined elsewhere 411 (i.e. serial_init(), serial_getc(), ...) 412 413 CONFIG_CFB_CONSOLE 414 Enables console device for a color framebuffer. Needs following 415 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 416 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 417 (default big endian) 418 VIDEO_HW_RECTFILL graphic chip supports 419 rectangle fill 420 (cf. smiLynxEM) 421 VIDEO_HW_BITBLT graphic chip supports 422 bit-blit (cf. smiLynxEM) 423 VIDEO_VISIBLE_COLS visible pixel columns 424 (cols=pitch) 425 VIDEO_VISIBLE_ROWS visible pixel rows 426 VIDEO_PIXEL_SIZE bytes per pixel 427 VIDEO_DATA_FORMAT graphic data format 428 (0-5, cf. cfb_console.c) 429 VIDEO_FB_ADRS framebuffer address 430 VIDEO_KBD_INIT_FCT keyboard int fct 431 (i.e. i8042_kbd_init()) 432 VIDEO_TSTC_FCT test char fct 433 (i.e. i8042_tstc) 434 VIDEO_GETC_FCT get char fct 435 (i.e. i8042_getc) 436 CONFIG_CONSOLE_CURSOR cursor drawing on/off 437 (requires blink timer 438 cf. i8042.c) 439 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 440 CONFIG_CONSOLE_TIME display time/date info in 441 upper right corner 442 (requires CFG_CMD_DATE) 443 CONFIG_VIDEO_LOGO display Linux logo in 444 upper left corner 445 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 446 linux_logo.h for logo. 447 Requires CONFIG_VIDEO_LOGO 448 CONFIG_CONSOLE_EXTRA_INFO 449 addional board info beside 450 the logo 451 452 When CONFIG_CFB_CONSOLE is defined, video console is 453 default i/o. Serial console can be forced with 454 environment 'console=serial'. 455 456- Console Baudrate: 457 CONFIG_BAUDRATE - in bps 458 Select one of the baudrates listed in 459 CFG_BAUDRATE_TABLE, see below. 460 461- Interrupt driven serial port input: 462 CONFIG_SERIAL_SOFTWARE_FIFO 463 464 PPC405GP only. 465 Use an interrupt handler for receiving data on the 466 serial port. It also enables using hardware handshake 467 (RTS/CTS) and UART's built-in FIFO. Set the number of 468 bytes the interrupt driven input buffer should have. 469 470 Set to 0 to disable this feature (this is the default). 471 This will also disable hardware handshake. 472 473- Boot Delay: CONFIG_BOOTDELAY - in seconds 474 Delay before automatically booting the default image; 475 set to -1 to disable autoboot. 476 477 See doc/README.autoboot for these options that 478 work with CONFIG_BOOTDELAY. None are required. 479 CONFIG_BOOT_RETRY_TIME 480 CONFIG_BOOT_RETRY_MIN 481 CONFIG_AUTOBOOT_KEYED 482 CONFIG_AUTOBOOT_PROMPT 483 CONFIG_AUTOBOOT_DELAY_STR 484 CONFIG_AUTOBOOT_STOP_STR 485 CONFIG_AUTOBOOT_DELAY_STR2 486 CONFIG_AUTOBOOT_STOP_STR2 487 CONFIG_ZERO_BOOTDELAY_CHECK 488 CONFIG_RESET_TO_RETRY 489 490- Autoboot Command: 491 CONFIG_BOOTCOMMAND 492 Only needed when CONFIG_BOOTDELAY is enabled; 493 define a command string that is automatically executed 494 when no character is read on the console interface 495 within "Boot Delay" after reset. 496 497 CONFIG_BOOTARGS 498 This can be used to pass arguments to the bootm 499 command. The value of CONFIG_BOOTARGS goes into the 500 environment value "bootargs". 501 502 CONFIG_RAMBOOT and CONFIG_NFSBOOT 503 The value of these goes into the environment as 504 "ramboot" and "nfsboot" respectively, and can be used 505 as a convenience, when switching between booting from 506 ram and nfs. 507 508- Pre-Boot Commands: 509 CONFIG_PREBOOT 510 511 When this option is #defined, the existence of the 512 environment variable "preboot" will be checked 513 immediately before starting the CONFIG_BOOTDELAY 514 countdown and/or running the auto-boot command resp. 515 entering interactive mode. 516 517 This feature is especially useful when "preboot" is 518 automatically generated or modified. For an example 519 see the LWMON board specific code: here "preboot" is 520 modified when the user holds down a certain 521 combination of keys on the (special) keyboard when 522 booting the systems 523 524- Serial Download Echo Mode: 525 CONFIG_LOADS_ECHO 526 If defined to 1, all characters received during a 527 serial download (using the "loads" command) are 528 echoed back. This might be needed by some terminal 529 emulations (like "cu"), but may as well just take 530 time on others. This setting #define's the initial 531 value of the "loads_echo" environment variable. 532 533- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined) 534 CONFIG_KGDB_BAUDRATE 535 Select one of the baudrates listed in 536 CFG_BAUDRATE_TABLE, see below. 537 538- Monitor Functions: 539 CONFIG_COMMANDS 540 Most monitor functions can be selected (or 541 de-selected) by adjusting the definition of 542 CONFIG_COMMANDS; to select individual functions, 543 #define CONFIG_COMMANDS by "OR"ing any of the 544 following values: 545 546 #define enables commands: 547 ------------------------- 548 CFG_CMD_ASKENV * ask for env variable 549 CFG_CMD_BDI bdinfo 550 CFG_CMD_BEDBUG Include BedBug Debugger 551 CFG_CMD_BOOTD bootd 552 CFG_CMD_CACHE icache, dcache 553 CFG_CMD_CONSOLE coninfo 554 CFG_CMD_DATE * support for RTC, date/time... 555 CFG_CMD_DHCP DHCP support 556 CFG_CMD_ECHO * echo arguments 557 CFG_CMD_EEPROM * EEPROM read/write support 558 CFG_CMD_ELF bootelf, bootvx 559 CFG_CMD_ENV saveenv 560 CFG_CMD_FDC * Floppy Disk Support 561 CFG_CMD_FDOS * Dos diskette Support 562 CFG_CMD_FLASH flinfo, erase, protect 563 CFG_CMD_FPGA FPGA device initialization support 564 CFG_CMD_I2C * I2C serial bus support 565 CFG_CMD_IDE * IDE harddisk support 566 CFG_CMD_IMI iminfo 567 CFG_CMD_IMMAP * IMMR dump support 568 CFG_CMD_IRQ * irqinfo 569 CFG_CMD_KGDB * kgdb 570 CFG_CMD_LOADB loadb 571 CFG_CMD_LOADS loads 572 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 573 loop, mtest 574 CFG_CMD_MII MII utility commands 575 CFG_CMD_NET bootp, tftpboot, rarpboot 576 CFG_CMD_PCI * pciinfo 577 CFG_CMD_PCMCIA * PCMCIA support 578 CFG_CMD_REGINFO * Register dump 579 CFG_CMD_RUN run command in env variable 580 CFG_CMD_SCSI * SCSI Support 581 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only) 582 CFG_CMD_SPI * SPI serial bus support 583 CFG_CMD_USB * USB support 584 CFG_CMD_BSP * Board SPecific functions 585 ----------------------------------------------- 586 CFG_CMD_ALL all 587 588 CFG_CMD_DFL Default configuration; at the moment 589 this is includes all commands, except 590 the ones marked with "*" in the list 591 above. 592 593 If you don't define CONFIG_COMMANDS it defaults to 594 CFG_CMD_DFL in include/cmd_confdefs.h. A board can 595 override the default settings in the respective 596 include file. 597 598 EXAMPLE: If you want all functions except of network 599 support you can write: 600 601 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET) 602 603 604 Note: Don't enable the "icache" and "dcache" commands 605 (configuration option CFG_CMD_CACHE) unless you know 606 what you (and your U-Boot users) are doing. Data 607 cache cannot be enabled on systems like the 8xx or 608 8260 (where accesses to the IMMR region must be 609 uncached), and it cannot be disabled on all other 610 systems where we (mis-) use the data cache to hold an 611 initial stack and some data. 612 613 614 XXX - this list needs to get updated! 615 616- Watchdog: 617 CONFIG_WATCHDOG 618 If this variable is defined, it enables watchdog 619 support. There must support in the platform specific 620 code for a watchdog. For the 8xx and 8260 CPUs, the 621 SIU Watchdog feature is enabled in the SYPCR 622 register. 623 624- U-Boot Version: 625 CONFIG_VERSION_VARIABLE 626 If this variable is defined, an environment variable 627 named "ver" is created by U-Boot showing the U-Boot 628 version as printed by the "version" command. 629 This variable is readonly. 630 631- Real-Time Clock: 632 633 When CFG_CMD_DATE is selected, the type of the RTC 634 has to be selected, too. Define exactly one of the 635 following options: 636 637 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 638 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 639 CONFIG_RTC_MC146818 - use MC146818 RTC 640 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 641 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 642 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 643 CONFIG_RTC_DS164x - use Dallas DS164x RTC 644 645- Timestamp Support: 646 647 When CONFIG_TIMESTAMP is selected, the timestamp 648 (date and time) of an image is printed by image 649 commands like bootm or iminfo. This option is 650 automatically enabled when you select CFG_CMD_DATE . 651 652- Partition Support: 653 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 654 and/or CONFIG_ISO_PARTITION 655 656 If IDE or SCSI support is enabled (CFG_CMD_IDE or 657 CFG_CMD_SCSI) you must configure support for at least 658 one partition type as well. 659 660- IDE Reset method: 661 CONFIG_IDE_RESET_ROUTINE 662 663 Set this to define that instead of a reset Pin, the 664 routine ide_set_reset(int idereset) will be used. 665 666- ATAPI Support: 667 CONFIG_ATAPI 668 669 Set this to enable ATAPI support. 670 671- SCSI Support: 672 At the moment only there is only support for the 673 SYM53C8XX SCSI controller; define 674 CONFIG_SCSI_SYM53C8XX to enable it. 675 676 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 677 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 678 CFG_SCSI_MAX_LUN] can be adjusted to define the 679 maximum numbers of LUNs, SCSI ID's and target 680 devices. 681 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 682 683- NETWORK Support (PCI): 684 CONFIG_EEPRO100 685 Support for Intel 82557/82559/82559ER chips. 686 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 687 write routine for first time initialisation. 688 689 CONFIG_TULIP 690 Support for Digital 2114x chips. 691 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 692 modem chip initialisation (KS8761/QS6611). 693 694 CONFIG_NATSEMI 695 Support for National dp83815 chips. 696 697 CONFIG_NS8382X 698 Support for National dp8382[01] gigabit chips. 699 700- NETWORK Support (other): 701 702 CONFIG_DRIVER_LAN91C96 703 Support for SMSC's LAN91C96 chips. 704 705 CONFIG_LAN91C96_BASE 706 Define this to hold the physical address 707 of the LAN91C96's I/O space 708 709 CONFIG_LAN91C96_USE_32_BIT 710 Define this to enable 32 bit addressing 711 712- USB Support: 713 At the moment only the UHCI host controller is 714 supported (PIP405, MIP405); define 715 CONFIG_USB_UHCI to enable it. 716 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 717 end define CONFIG_USB_STORAGE to enable the USB 718 storage devices. 719 Note: 720 Supported are USB Keyboards and USB Floppy drives 721 (TEAC FD-05PUB). 722 723- Keyboard Support: 724 CONFIG_ISA_KEYBOARD 725 726 Define this to enable standard (PC-Style) keyboard 727 support 728 729 CONFIG_I8042_KBD 730 Standard PC keyboard driver with US (is default) and 731 GERMAN key layout (switch via environment 'keymap=de') support. 732 Export function i8042_kbd_init, i8042_tstc and i8042_getc 733 for cfb_console. Supports cursor blinking. 734 735- Video support: 736 CONFIG_VIDEO 737 738 Define this to enable video support (for output to 739 video). 740 741 CONFIG_VIDEO_CT69000 742 743 Enable Chips & Technologies 69000 Video chip 744 745 CONFIG_VIDEO_SMI_LYNXEM 746 Enable Silicon Motion SMI 712/710/810 Video chip 747 Videomode are selected via environment 'videomode' with 748 standard LiLo mode numbers. 749 Following modes are supported (* is default): 750 751 800x600 1024x768 1280x1024 752 256 (8bit) 303* 305 307 753 65536 (16bit) 314 317 31a 754 16,7 Mill (24bit) 315 318 31b 755 (i.e. setenv videomode 317; saveenv; reset;) 756 757 CONFIG_VIDEO_SED13806 758 Enable Epson SED13806 driver. This driver supports 8bpp 759 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 760 or CONFIG_VIDEO_SED13806_16BPP 761 762 763- LCD Support: CONFIG_LCD 764 765 Define this to enable LCD support (for output to LCD 766 display); also select one of the supported displays 767 by defining one of these: 768 769 CONFIG_NEC_NL6648AC33: 770 771 NEC NL6648AC33-18. Active, color, single scan. 772 773 CONFIG_NEC_NL6648BC20 774 775 NEC NL6648BC20-08. 6.5", 640x480. 776 Active, color, single scan. 777 778 CONFIG_SHARP_16x9 779 780 Sharp 320x240. Active, color, single scan. 781 It isn't 16x9, and I am not sure what it is. 782 783 CONFIG_SHARP_LQ64D341 784 785 Sharp LQ64D341 display, 640x480. 786 Active, color, single scan. 787 788 CONFIG_HLD1045 789 790 HLD1045 display, 640x480. 791 Active, color, single scan. 792 793 CONFIG_OPTREX_BW 794 795 Optrex CBL50840-2 NF-FW 99 22 M5 796 or 797 Hitachi LMG6912RPFC-00T 798 or 799 Hitachi SP14Q002 800 801 320x240. Black & white. 802 803 Normally display is black on white background; define 804 CFG_WHITE_ON_BLACK to get it inverted. 805 806- Spash Screen Support: CONFIG_SPLASH_SCREEN 807 808 If this option is set, the environment is checked for 809 a variable "splashimage". If found, the usual display 810 of logo, copyright and system information on the LCD 811 is supressed and the BMP image at the address 812 specified in "splashimage" is loaded instead. The 813 console is redirected to the "nulldev", too. This 814 allows for a "silent" boot where a splash screen is 815 loaded very quickly after power-on. 816 817 818- Ethernet address: 819 CONFIG_ETHADDR 820 CONFIG_ETH2ADDR 821 CONFIG_ETH3ADDR 822 823 Define a default value for ethernet address to use 824 for the respective ethernet interface, in case this 825 is not determined automatically. 826 827- IP address: 828 CONFIG_IPADDR 829 830 Define a default value for the IP address to use for 831 the default ethernet interface, in case this is not 832 determined through e.g. bootp. 833 834- Server IP address: 835 CONFIG_SERVERIP 836 837 Defines a default value for theIP address of a TFTP 838 server to contact when using the "tftboot" command. 839 840- BOOTP Recovery Mode: 841 CONFIG_BOOTP_RANDOM_DELAY 842 843 If you have many targets in a network that try to 844 boot using BOOTP, you may want to avoid that all 845 systems send out BOOTP requests at precisely the same 846 moment (which would happen for instance at recovery 847 from a power failure, when all systems will try to 848 boot, thus flooding the BOOTP server. Defining 849 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 850 inserted before sending out BOOTP requests. The 851 following delays are insterted then: 852 853 1st BOOTP request: delay 0 ... 1 sec 854 2nd BOOTP request: delay 0 ... 2 sec 855 3rd BOOTP request: delay 0 ... 4 sec 856 4th and following 857 BOOTP requests: delay 0 ... 8 sec 858 859- Status LED: CONFIG_STATUS_LED 860 861 Several configurations allow to display the current 862 status using a LED. For instance, the LED will blink 863 fast while running U-Boot code, stop blinking as 864 soon as a reply to a BOOTP request was received, and 865 start blinking slow once the Linux kernel is running 866 (supported by a status LED driver in the Linux 867 kernel). Defining CONFIG_STATUS_LED enables this 868 feature in U-Boot. 869 870- CAN Support: CONFIG_CAN_DRIVER 871 872 Defining CONFIG_CAN_DRIVER enables CAN driver support 873 on those systems that support this (optional) 874 feature, like the TQM8xxL modules. 875 876- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 877 878 Enables I2C serial bus commands. If this is selected, 879 either CONFIG_HARD_I2C or CONFIG_SOFT_I2C must be defined 880 to include the appropriate I2C driver. 881 882 See also: common/cmd_i2c.c for a description of the 883 command line interface. 884 885 886 CONFIG_HARD_I2C 887 888 Selects the CPM hardware driver for I2C. 889 890 CONFIG_SOFT_I2C 891 892 Use software (aka bit-banging) driver instead of CPM 893 or similar hardware support for I2C. This is configured 894 via the following defines. 895 896 I2C_INIT 897 898 (Optional). Any commands necessary to enable I2C 899 controller or configure ports. 900 901 I2C_PORT 902 903 (Only for MPC8260 CPU). The I/O port to use (the code 904 assumes both bits are on the same port). Valid values 905 are 0..3 for ports A..D. 906 907 I2C_ACTIVE 908 909 The code necessary to make the I2C data line active 910 (driven). If the data line is open collector, this 911 define can be null. 912 913 I2C_TRISTATE 914 915 The code necessary to make the I2C data line tri-stated 916 (inactive). If the data line is open collector, this 917 define can be null. 918 919 I2C_READ 920 921 Code that returns TRUE if the I2C data line is high, 922 FALSE if it is low. 923 924 I2C_SDA(bit) 925 926 If <bit> is TRUE, sets the I2C data line high. If it 927 is FALSE, it clears it (low). 928 929 I2C_SCL(bit) 930 931 If <bit> is TRUE, sets the I2C clock line high. If it 932 is FALSE, it clears it (low). 933 934 I2C_DELAY 935 936 This delay is invoked four times per clock cycle so this 937 controls the rate of data transfer. The data rate thus 938 is 1 / (I2C_DELAY * 4). 939 940 CFG_I2C_INIT_BOARD 941 942 When a board is reset during an i2c bus transfer 943 chips might think that the current transfer is still 944 in progress. On some boards it is possible to access 945 the i2c SCLK line directly, either by using the 946 processor pin as a GPIO or by having a second pin 947 connected to the bus. If this option is defined a 948 custom i2c_init_board() routine in boards/xxx/board.c 949 is run early in the boot sequence. 950 951- SPI Support: CONFIG_SPI 952 953 Enables SPI driver (so far only tested with 954 SPI EEPROM, also an instance works with Crystal A/D and 955 D/As on the SACSng board) 956 957 CONFIG_SPI_X 958 959 Enables extended (16-bit) SPI EEPROM addressing. 960 (symmetrical to CONFIG_I2C_X) 961 962 CONFIG_SOFT_SPI 963 964 Enables a software (bit-bang) SPI driver rather than 965 using hardware support. This is a general purpose 966 driver that only requires three general I/O port pins 967 (two outputs, one input) to function. If this is 968 defined, the board configuration must define several 969 SPI configuration items (port pins to use, etc). For 970 an example, see include/configs/sacsng.h. 971 972- FPGA Support: CONFIG_FPGA_COUNT 973 974 Specify the number of FPGA devices to support. 975 976 CONFIG_FPGA 977 978 Used to specify the types of FPGA devices. For 979 example, 980 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 981 982 CFG_FPGA_PROG_FEEDBACK 983 984 Enable printing of hash marks during FPGA 985 configuration. 986 987 CFG_FPGA_CHECK_BUSY 988 989 Enable checks on FPGA configuration interface busy 990 status by the configuration function. This option 991 will require a board or device specific function to 992 be written. 993 994 CONFIG_FPGA_DELAY 995 996 If defined, a function that provides delays in the 997 FPGA configuration driver. 998 999 CFG_FPGA_CHECK_CTRLC 1000 1001 Allow Control-C to interrupt FPGA configuration 1002 1003 CFG_FPGA_CHECK_ERROR 1004 1005 Check for configuration errors during FPGA bitfile 1006 loading. For example, abort during Virtex II 1007 configuration if the INIT_B line goes low (which 1008 indicated a CRC error). 1009 1010 CFG_FPGA_WAIT_INIT 1011 1012 Maximum time to wait for the INIT_B line to deassert 1013 after PROB_B has been deasserted during a Virtex II 1014 FPGA configuration sequence. The default time is 500 mS. 1015 1016 CFG_FPGA_WAIT_BUSY 1017 1018 Maximum time to wait for BUSY to deassert during 1019 Virtex II FPGA configuration. The default is 5 mS. 1020 1021 CFG_FPGA_WAIT_CONFIG 1022 1023 Time to wait after FPGA configuration. The default is 1024 200 mS. 1025 1026- FPGA Support: CONFIG_FPGA_COUNT 1027 1028 Specify the number of FPGA devices to support. 1029 1030 CONFIG_FPGA 1031 1032 Used to specify the types of FPGA devices. For example, 1033 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 1034 1035 CFG_FPGA_PROG_FEEDBACK 1036 1037 Enable printing of hash marks during FPGA configuration. 1038 1039 CFG_FPGA_CHECK_BUSY 1040 1041 Enable checks on FPGA configuration interface busy 1042 status by the configuration function. This option 1043 will require a board or device specific function to 1044 be written. 1045 1046 CONFIG_FPGA_DELAY 1047 1048 If defined, a function that provides delays in the FPGA 1049 configuration driver. 1050 1051 CFG_FPGA_CHECK_CTRLC 1052 Allow Control-C to interrupt FPGA configuration 1053 1054 CFG_FPGA_CHECK_ERROR 1055 1056 Check for configuration errors during FPGA bitfile 1057 loading. For example, abort during Virtex II 1058 configuration if the INIT_B line goes low (which 1059 indicated a CRC error). 1060 1061 CFG_FPGA_WAIT_INIT 1062 1063 Maximum time to wait for the INIT_B line to deassert 1064 after PROB_B has been deasserted during a Virtex II 1065 FPGA configuration sequence. The default time is 500 1066 mS. 1067 1068 CFG_FPGA_WAIT_BUSY 1069 1070 Maximum time to wait for BUSY to deassert during 1071 Virtex II FPGA configuration. The default is 5 mS. 1072 1073 CFG_FPGA_WAIT_CONFIG 1074 1075 Time to wait after FPGA configuration. The default is 1076 200 mS. 1077 1078- Configuration Management: 1079 CONFIG_IDENT_STRING 1080 1081 If defined, this string will be added to the U-Boot 1082 version information (U_BOOT_VERSION) 1083 1084- Vendor Parameter Protection: 1085 1086 U-Boot considers the values of the environment 1087 variables "serial#" (Board Serial Number) and 1088 "ethaddr" (Ethernet Address) to bb parameters that 1089 are set once by the board vendor / manufacturer, and 1090 protects these variables from casual modification by 1091 the user. Once set, these variables are read-only, 1092 and write or delete attempts are rejected. You can 1093 change this behviour: 1094 1095 If CONFIG_ENV_OVERWRITE is #defined in your config 1096 file, the write protection for vendor parameters is 1097 completely disabled. Anybody can change or delete 1098 these parameters. 1099 1100 Alternatively, if you #define _both_ CONFIG_ETHADDR 1101 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1102 ethernet address is installed in the environment, 1103 which can be changed exactly ONCE by the user. [The 1104 serial# is unaffected by this, i. e. it remains 1105 read-only.] 1106 1107- Protected RAM: 1108 CONFIG_PRAM 1109 1110 Define this variable to enable the reservation of 1111 "protected RAM", i. e. RAM which is not overwritten 1112 by U-Boot. Define CONFIG_PRAM to hold the number of 1113 kB you want to reserve for pRAM. You can overwrite 1114 this default value by defining an environment 1115 variable "pram" to the number of kB you want to 1116 reserve. Note that the board info structure will 1117 still show the full amount of RAM. If pRAM is 1118 reserved, a new environment variable "mem" will 1119 automatically be defined to hold the amount of 1120 remaining RAM in a form that can be passed as boot 1121 argument to Linux, for instance like that: 1122 1123 setenv bootargs ... mem=\$(mem) 1124 saveenv 1125 1126 This way you can tell Linux not to use this memory, 1127 either, which results in a memory region that will 1128 not be affected by reboots. 1129 1130 *WARNING* If your board configuration uses automatic 1131 detection of the RAM size, you must make sure that 1132 this memory test is non-destructive. So far, the 1133 following board configurations are known to be 1134 "pRAM-clean": 1135 1136 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1137 HERMES, IP860, RPXlite, LWMON, LANTEC, 1138 PCU_E, FLAGADM, TQM8260 1139 1140- Error Recovery: 1141 CONFIG_PANIC_HANG 1142 1143 Define this variable to stop the system in case of a 1144 fatal error, so that you have to reset it manually. 1145 This is probably NOT a good idea for an embedded 1146 system where you want to system to reboot 1147 automatically as fast as possible, but it may be 1148 useful during development since you can try to debug 1149 the conditions that lead to the situation. 1150 1151 CONFIG_NET_RETRY_COUNT 1152 1153 This variable defines the number of retries for 1154 network operations like ARP, RARP, TFTP, or BOOTP 1155 before giving up the operation. If not defined, a 1156 default value of 5 is used. 1157 1158- Command Interpreter: 1159 CFG_HUSH_PARSER 1160 1161 Define this variable to enable the "hush" shell (from 1162 Busybox) as command line interpreter, thus enabling 1163 powerful command line syntax like 1164 if...then...else...fi conditionals or `&&' and '||' 1165 constructs ("shell scripts"). 1166 1167 If undefined, you get the old, much simpler behaviour 1168 with a somewhat smaller memory footprint. 1169 1170 1171 CFG_PROMPT_HUSH_PS2 1172 1173 This defines the secondary prompt string, which is 1174 printed when the command interpreter needs more input 1175 to complete a command. Usually "> ". 1176 1177 Note: 1178 1179 In the current implementation, the local variables 1180 space and global environment variables space are 1181 separated. Local variables are those you define by 1182 simply typing like `name=value'. To access a local 1183 variable later on, you have write `$name' or 1184 `${name}'; variable directly by typing say `$name' at 1185 the command prompt. 1186 1187 Global environment variables are those you use 1188 setenv/printenv to work with. To run a command stored 1189 in such a variable, you need to use the run command, 1190 and you must not use the '$' sign to access them. 1191 1192 To store commands and special characters in a 1193 variable, please use double quotation marks 1194 surrounding the whole text of the variable, instead 1195 of the backslashes before semicolons and special 1196 symbols. 1197 1198- Default Environment 1199 CONFIG_EXTRA_ENV_SETTINGS 1200 1201 Define this to contain any number of null terminated 1202 strings (variable = value pairs) that will be part of 1203 the default enviroment compiled into the boot image. 1204 1205 For example, place something like this in your 1206 board's config file: 1207 1208 #define CONFIG_EXTRA_ENV_SETTINGS \ 1209 "myvar1=value1\0" \ 1210 "myvar2=value2\0" 1211 1212 Warning: This method is based on knowledge about the 1213 internal format how the environment is stored by the 1214 U-Boot code. This is NOT an official, exported 1215 interface! Although it is unlikely that this format 1216 will change soon, but there is no guarantee either. 1217 You better know what you are doing here. 1218 1219 Note: overly (ab)use of the default environment is 1220 discouraged. Make sure to check other ways to preset 1221 the environment like the autoscript function or the 1222 boot command first. 1223 1224- Show boot progress 1225 CONFIG_SHOW_BOOT_PROGRESS 1226 1227 Defining this option allows to add some board- 1228 specific code (calling a user-provided function 1229 "show_boot_progress(int)") that enables you to show 1230 the system's boot progress on some display (for 1231 example, some LED's) on your board. At the moment, 1232 the following checkpoints are implemented: 1233 1234 Arg Where When 1235 1 common/cmd_bootm.c before attempting to boot an image 1236 -1 common/cmd_bootm.c Image header has bad magic number 1237 2 common/cmd_bootm.c Image header has correct magic number 1238 -2 common/cmd_bootm.c Image header has bad checksum 1239 3 common/cmd_bootm.c Image header has correct checksum 1240 -3 common/cmd_bootm.c Image data has bad checksum 1241 4 common/cmd_bootm.c Image data has correct checksum 1242 -4 common/cmd_bootm.c Image is for unsupported architecture 1243 5 common/cmd_bootm.c Architecture check OK 1244 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1245 6 common/cmd_bootm.c Image Type check OK 1246 -6 common/cmd_bootm.c gunzip uncompression error 1247 -7 common/cmd_bootm.c Unimplemented compression type 1248 7 common/cmd_bootm.c Uncompression OK 1249 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1250 8 common/cmd_bootm.c Image Type check OK 1251 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1252 9 common/cmd_bootm.c Start initial ramdisk verification 1253 -10 common/cmd_bootm.c Ramdisk header has bad magic number 1254 -11 common/cmd_bootm.c Ramdisk header has bad checksum 1255 10 common/cmd_bootm.c Ramdisk header is OK 1256 -12 common/cmd_bootm.c Ramdisk data has bad checksum 1257 11 common/cmd_bootm.c Ramdisk data has correct checksum 1258 12 common/cmd_bootm.c Ramdisk verification complete, start loading 1259 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk) 1260 13 common/cmd_bootm.c Start multifile image verification 1261 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue. 1262 15 common/cmd_bootm.c All preparation done, transferring control to OS 1263 1264 -1 common/cmd_doc.c Bad usage of "doc" command 1265 -1 common/cmd_doc.c No boot device 1266 -1 common/cmd_doc.c Unknown Chip ID on boot device 1267 -1 common/cmd_doc.c Read Error on boot device 1268 -1 common/cmd_doc.c Image header has bad magic number 1269 1270 -1 common/cmd_ide.c Bad usage of "ide" command 1271 -1 common/cmd_ide.c No boot device 1272 -1 common/cmd_ide.c Unknown boot device 1273 -1 common/cmd_ide.c Unknown partition table 1274 -1 common/cmd_ide.c Invalid partition type 1275 -1 common/cmd_ide.c Read Error on boot device 1276 -1 common/cmd_ide.c Image header has bad magic number 1277 1278 -1 common/cmd_nvedit.c Environment not changable, but has bad CRC 1279 1280 1281Modem Support: 1282-------------- 1283 1284[so far only for SMDK2400 and TRAB boards] 1285 1286- Modem support endable: 1287 CONFIG_MODEM_SUPPORT 1288 1289- RTS/CTS Flow control enable: 1290 CONFIG_HWFLOW 1291 1292- Modem debug support: 1293 CONFIG_MODEM_SUPPORT_DEBUG 1294 1295 Enables debugging stuff (char screen[1024], dbg()) 1296 for modem support. Useful only with BDI2000. 1297 1298- General: 1299 1300 In the target system modem support is enabled when a 1301 specific key (key combination) is pressed during 1302 power-on. Otherwise U-Boot will boot normally 1303 (autoboot). The key_pressed() fuction is called from 1304 board_init(). Currently key_pressed() is a dummy 1305 function, returning 1 and thus enabling modem 1306 initialization. 1307 1308 If there are no modem init strings in the 1309 environment, U-Boot proceed to autoboot; the 1310 previous output (banner, info printfs) will be 1311 supressed, though. 1312 1313 See also: doc/README.Modem 1314 1315 1316 1317 1318Configuration Settings: 1319----------------------- 1320 1321- CFG_LONGHELP: Defined when you want long help messages included; 1322 undefine this when you're short of memory. 1323 1324- CFG_PROMPT: This is what U-Boot prints on the console to 1325 prompt for user input. 1326 1327- CFG_CBSIZE: Buffer size for input from the Console 1328 1329- CFG_PBSIZE: Buffer size for Console output 1330 1331- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1332 1333- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1334 the application (usually a Linux kernel) when it is 1335 booted 1336 1337- CFG_BAUDRATE_TABLE: 1338 List of legal baudrate settings for this board. 1339 1340- CFG_CONSOLE_INFO_QUIET 1341 Suppress display of console information at boot. 1342 1343- CFG_CONSOLE_IS_IN_ENV 1344 If the board specific function 1345 extern int overwrite_console (void); 1346 returns 1, the stdin, stderr and stdout are switched to the 1347 serial port, else the settings in the environment are used. 1348 1349- CFG_CONSOLE_OVERWRITE_ROUTINE 1350 Enable the call to overwrite_console(). 1351 1352- CFG_CONSOLE_ENV_OVERWRITE 1353 Enable overwrite of previous console environment settings. 1354 1355- CFG_MEMTEST_START, CFG_MEMTEST_END: 1356 Begin and End addresses of the area used by the 1357 simple memory test. 1358 1359- CFG_ALT_MEMTEST: 1360 Enable an alternate, more extensive memory test. 1361 1362- CFG_TFTP_LOADADDR: 1363 Default load address for network file downloads 1364 1365- CFG_LOADS_BAUD_CHANGE: 1366 Enable temporary baudrate change while serial download 1367 1368- CFG_SDRAM_BASE: 1369 Physical start address of SDRAM. _Must_ be 0 here. 1370 1371- CFG_MBIO_BASE: 1372 Physical start address of Motherboard I/O (if using a 1373 Cogent motherboard) 1374 1375- CFG_FLASH_BASE: 1376 Physical start address of Flash memory. 1377 1378- CFG_MONITOR_BASE: 1379 Physical start address of boot monitor code (set by 1380 make config files to be same as the text base address 1381 (TEXT_BASE) used when linking) - same as 1382 CFG_FLASH_BASE when booting from flash. 1383 1384- CFG_MONITOR_LEN: 1385 Size of memory reserved for monitor code 1386 1387- CFG_MALLOC_LEN: 1388 Size of DRAM reserved for malloc() use. 1389 1390- CFG_BOOTMAPSZ: 1391 Maximum size of memory mapped by the startup code of 1392 the Linux kernel; all data that must be processed by 1393 the Linux kernel (bd_info, boot arguments, eventually 1394 initrd image) must be put below this limit. 1395 1396- CFG_MAX_FLASH_BANKS: 1397 Max number of Flash memory banks 1398 1399- CFG_MAX_FLASH_SECT: 1400 Max number of sectors on a Flash chip 1401 1402- CFG_FLASH_ERASE_TOUT: 1403 Timeout for Flash erase operations (in ms) 1404 1405- CFG_FLASH_WRITE_TOUT: 1406 Timeout for Flash write operations (in ms) 1407 1408- CFG_DIRECT_FLASH_TFTP: 1409 1410 Enable TFTP transfers directly to flash memory; 1411 without this option such a download has to be 1412 performed in two steps: (1) download to RAM, and (2) 1413 copy from RAM to flash. 1414 1415 The two-step approach is usually more reliable, since 1416 you can check if the download worked before you erase 1417 the flash, but in some situations (when sytem RAM is 1418 too limited to allow for a tempory copy of the 1419 downloaded image) this option may be very useful. 1420 1421- CFG_FLASH_CFI: 1422 Define if the flash driver uses extra elements in the 1423 common flash structure for storing flash geometry 1424 1425The following definitions that deal with the placement and management 1426of environment data (variable area); in general, we support the 1427following configurations: 1428 1429- CFG_ENV_IS_IN_FLASH: 1430 1431 Define this if the environment is in flash memory. 1432 1433 a) The environment occupies one whole flash sector, which is 1434 "embedded" in the text segment with the U-Boot code. This 1435 happens usually with "bottom boot sector" or "top boot 1436 sector" type flash chips, which have several smaller 1437 sectors at the start or the end. For instance, such a 1438 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 1439 such a case you would place the environment in one of the 1440 4 kB sectors - with U-Boot code before and after it. With 1441 "top boot sector" type flash chips, you would put the 1442 environment in one of the last sectors, leaving a gap 1443 between U-Boot and the environment. 1444 1445 - CFG_ENV_OFFSET: 1446 1447 Offset of environment data (variable area) to the 1448 beginning of flash memory; for instance, with bottom boot 1449 type flash chips the second sector can be used: the offset 1450 for this sector is given here. 1451 1452 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 1453 1454 - CFG_ENV_ADDR: 1455 1456 This is just another way to specify the start address of 1457 the flash sector containing the environment (instead of 1458 CFG_ENV_OFFSET). 1459 1460 - CFG_ENV_SECT_SIZE: 1461 1462 Size of the sector containing the environment. 1463 1464 1465 b) Sometimes flash chips have few, equal sized, BIG sectors. 1466 In such a case you don't want to spend a whole sector for 1467 the environment. 1468 1469 - CFG_ENV_SIZE: 1470 1471 If you use this in combination with CFG_ENV_IS_IN_FLASH 1472 and CFG_ENV_SECT_SIZE, you can specify to use only a part 1473 of this flash sector for the environment. This saves 1474 memory for the RAM copy of the environment. 1475 1476 It may also save flash memory if you decide to use this 1477 when your environment is "embedded" within U-Boot code, 1478 since then the remainder of the flash sector could be used 1479 for U-Boot code. It should be pointed out that this is 1480 STRONGLY DISCOURAGED from a robustness point of view: 1481 updating the environment in flash makes it always 1482 necessary to erase the WHOLE sector. If something goes 1483 wrong before the contents has been restored from a copy in 1484 RAM, your target system will be dead. 1485 1486 - CFG_ENV_ADDR_REDUND 1487 CFG_ENV_SIZE_REDUND 1488 1489 These settings describe a second storage area used to hold 1490 a redundand copy of the environment data, so that there is 1491 a valid backup copy in case there is a power failure during 1492 a "saveenv" operation. 1493 1494BE CAREFUL! Any changes to the flash layout, and some changes to the 1495source code will make it necessary to adapt <board>/u-boot.lds* 1496accordingly! 1497 1498 1499- CFG_ENV_IS_IN_NVRAM: 1500 1501 Define this if you have some non-volatile memory device 1502 (NVRAM, battery buffered SRAM) which you want to use for the 1503 environment. 1504 1505 - CFG_ENV_ADDR: 1506 - CFG_ENV_SIZE: 1507 1508 These two #defines are used to determin the memory area you 1509 want to use for environment. It is assumed that this memory 1510 can just be read and written to, without any special 1511 provision. 1512 1513BE CAREFUL! The first access to the environment happens quite early 1514in U-Boot initalization (when we try to get the setting of for the 1515console baudrate). You *MUST* have mappend your NVRAM area then, or 1516U-Boot will hang. 1517 1518Please note that even with NVRAM we still use a copy of the 1519environment in RAM: we could work on NVRAM directly, but we want to 1520keep settings there always unmodified except somebody uses "saveenv" 1521to save the current settings. 1522 1523 1524- CFG_ENV_IS_IN_EEPROM: 1525 1526 Use this if you have an EEPROM or similar serial access 1527 device and a driver for it. 1528 1529 - CFG_ENV_OFFSET: 1530 - CFG_ENV_SIZE: 1531 1532 These two #defines specify the offset and size of the 1533 environment area within the total memory of your EEPROM. 1534 1535 - CFG_I2C_EEPROM_ADDR: 1536 If defined, specified the chip address of the EEPROM device. 1537 The default address is zero. 1538 1539 - CFG_EEPROM_PAGE_WRITE_BITS: 1540 If defined, the number of bits used to address bytes in a 1541 single page in the EEPROM device. A 64 byte page, for example 1542 would require six bits. 1543 1544 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 1545 If defined, the number of milliseconds to delay between 1546 page writes. The default is zero milliseconds. 1547 1548 - CFG_I2C_EEPROM_ADDR_LEN: 1549 The length in bytes of the EEPROM memory array address. Note 1550 that this is NOT the chip address length! 1551 1552 - CFG_EEPROM_SIZE: 1553 The size in bytes of the EEPROM device. 1554 1555 1556- CFG_SPI_INIT_OFFSET 1557 1558 Defines offset to the initial SPI buffer area in DPRAM. The 1559 area is used at an early stage (ROM part) if the environment 1560 is configured to reside in the SPI EEPROM: We need a 520 byte 1561 scratch DPRAM area. It is used between the two initialization 1562 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 1563 to be a good choice since it makes it far enough from the 1564 start of the data area as well as from the stack pointer. 1565 1566Please note that the environment is read-only as long as the monitor 1567has been relocated to RAM and a RAM copy of the environment has been 1568created; also, when using EEPROM you will have to use getenv_r() 1569until then to read environment variables. 1570 1571The environment is protected by a CRC32 checksum. Before the monitor 1572is relocated into RAM, as a result of a bad CRC you will be working 1573with the compiled-in default environment - *silently*!!! [This is 1574necessary, because the first environment variable we need is the 1575"baudrate" setting for the console - if we have a bad CRC, we don't 1576have any device yet where we could complain.] 1577 1578Note: once the monitor has been relocated, then it will complain if 1579the default environment is used; a new CRC is computed as soon as you 1580use the "saveenv" command to store a valid environment. 1581 1582 1583Low Level (hardware related) configuration options: 1584--------------------------------------------------- 1585 1586- CFG_CACHELINE_SIZE: 1587 Cache Line Size of the CPU. 1588 1589- CFG_DEFAULT_IMMR: 1590 Default address of the IMMR after system reset. 1591 Needed on some 8260 systems (MPC8260ADS and RPXsuper) 1592 to be able to adjust the position of the IMMR 1593 register after a reset. 1594 1595- Floppy Disk Support: 1596 CFG_FDC_DRIVE_NUMBER 1597 1598 the default drive number (default value 0) 1599 1600 CFG_ISA_IO_STRIDE 1601 1602 defines the spacing between fdc chipset registers 1603 (default value 1) 1604 1605 CFG_ISA_IO_OFFSET 1606 1607 defines the offset of register from address. It 1608 depends on which part of the data bus is connected to 1609 the fdc chipset. (default value 0) 1610 1611 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 1612 CFG_FDC_DRIVE_NUMBER are undefined, they take their 1613 default value. 1614 1615 if CFG_FDC_HW_INIT is defined, then the function 1616 fdc_hw_init() is called at the beginning of the FDC 1617 setup. fdc_hw_init() must be provided by the board 1618 source code. It is used to make hardware dependant 1619 initializations. 1620 1621- CFG_IMMR: Physical address of the Internal Memory Mapped 1622 Register; DO NOT CHANGE! (11-4) 1623 [MPC8xx systems only] 1624 1625- CFG_INIT_RAM_ADDR: 1626 1627 Start address of memory area tha can be used for 1628 initial data and stack; please note that this must be 1629 writable memory that is working WITHOUT special 1630 initialization, i. e. you CANNOT use normal RAM which 1631 will become available only after programming the 1632 memory controller and running certain initialization 1633 sequences. 1634 1635 U-Boot uses the following memory types: 1636 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 1637 - MPC824X: data cache 1638 - PPC4xx: data cache 1639 1640- CFG_GBL_DATA_OFFSET: 1641 1642 Offset of the initial data structure in the memory 1643 area defined by CFG_INIT_RAM_ADDR. Usually 1644 CFG_GBL_DATA_OFFSET is chosen such that the initial 1645 data is located at the end of the available space 1646 (sometimes written as (CFG_INIT_RAM_END - 1647 CFG_INIT_DATA_SIZE), and the initial stack is just 1648 below that area (growing from (CFG_INIT_RAM_ADDR + 1649 CFG_GBL_DATA_OFFSET) downward. 1650 1651 Note: 1652 On the MPC824X (or other systems that use the data 1653 cache for initial memory) the address chosen for 1654 CFG_INIT_RAM_ADDR is basically arbitrary - it must 1655 point to an otherwise UNUSED address space between 1656 the top of RAM and the start of the PCI space. 1657 1658- CFG_SIUMCR: SIU Module Configuration (11-6) 1659 1660- CFG_SYPCR: System Protection Control (11-9) 1661 1662- CFG_TBSCR: Time Base Status and Control (11-26) 1663 1664- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 1665 1666- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 1667 1668- CFG_SCCR: System Clock and reset Control Register (15-27) 1669 1670- CFG_OR_TIMING_SDRAM: 1671 SDRAM timing 1672 1673- CFG_MAMR_PTA: 1674 periodic timer for refresh 1675 1676- CFG_DER: Debug Event Register (37-47) 1677 1678- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 1679 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 1680 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 1681 CFG_BR1_PRELIM: 1682 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 1683 1684- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 1685 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 1686 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 1687 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 1688 1689- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 1690 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 1691 Machine Mode Register and Memory Periodic Timer 1692 Prescaler definitions (SDRAM timing) 1693 1694- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 1695 enable I2C microcode relocation patch (MPC8xx); 1696 define relocation offset in DPRAM [DSP2] 1697 1698- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 1699 enable SPI microcode relocation patch (MPC8xx); 1700 define relocation offset in DPRAM [SCC4] 1701 1702- CFG_USE_OSCCLK: 1703 Use OSCM clock mode on MBX8xx board. Be careful, 1704 wrong setting might damage your board. Read 1705 doc/README.MBX before setting this variable! 1706 1707- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 1708 Offset of the bootmode word in DPRAM used by post 1709 (Power On Self Tests). This definition overrides 1710 #define'd default value in commproc.h resp. 1711 cpm_8260.h. 1712 1713Building the Software: 1714====================== 1715 1716Building U-Boot has been tested in native PPC environments (on a 1717PowerBook G3 running LinuxPPC 2000) and in cross environments 1718(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and 1719NetBSD 1.5 on x86). 1720 1721If you are not using a native PPC environment, it is assumed that you 1722have the GNU cross compiling tools available in your path and named 1723with a prefix of "powerpc-linux-". If this is not the case, (e.g. if 1724you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change 1725the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU, 1726change it to: 1727 1728 CROSS_COMPILE = ppc_4xx- 1729 1730 1731U-Boot is intended to be simple to build. After installing the 1732sources you must configure U-Boot for one specific board type. This 1733is done by typing: 1734 1735 make NAME_config 1736 1737where "NAME_config" is the name of one of the existing 1738configurations; the following names are supported: 1739 1740 ADCIOP_config GTH_config TQM850L_config 1741 ADS860_config IP860_config TQM855L_config 1742 AR405_config IVML24_config TQM860L_config 1743 CANBT_config IVMS8_config WALNUT405_config 1744 CPCI405_config LANTEC_config cogent_common_config 1745 CPCIISER4_config MBX_config cogent_mpc8260_config 1746 CU824_config MBX860T_config cogent_mpc8xx_config 1747 ESTEEM192E_config RPXlite_config hermes_config 1748 ETX094_config RPXsuper_config hymod_config 1749 FADS823_config SM850_config lwmon_config 1750 FADS850SAR_config SPD823TS_config pcu_e_config 1751 FADS860T_config SXNI855T_config rsdproto_config 1752 FPS850L_config Sandpoint8240_config sbc8260_config 1753 GENIETV_config TQM823L_config PIP405_config 1754 GEN860T_config EBONY_config FPS860L_config 1755 ELPT860_config cmi_mpc5xx_config NETVIA_config 1756 1757Note: for some board special configuration names may exist; check if 1758 additional information is available from the board vendor; for 1759 instance, the TQM8xxL systems run normally at 50 MHz and use a 1760 SCC for 10baseT ethernet; there are also systems with 80 MHz 1761 CPU clock, and an optional Fast Ethernet module is available 1762 for CPU's with FEC. You can select such additional "features" 1763 when chosing the configuration, i. e. 1764 1765 make TQM860L_config 1766 - will configure for a plain TQM860L, i. e. 50MHz, no FEC 1767 1768 make TQM860L_FEC_config 1769 - will configure for a TQM860L at 50MHz with FEC for ethernet 1770 1771 make TQM860L_80MHz_config 1772 - will configure for a TQM860L at 80 MHz, with normal 10baseT 1773 interface 1774 1775 make TQM860L_FEC_80MHz_config 1776 - will configure for a TQM860L at 80 MHz with FEC for ethernet 1777 1778 make TQM823L_LCD_config 1779 - will configure for a TQM823L with U-Boot console on LCD 1780 1781 make TQM823L_LCD_80MHz_config 1782 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD 1783 1784 etc. 1785 1786 1787 1788Finally, type "make all", and you should get some working U-Boot 1789images ready for downlod to / installation on your system: 1790 1791- "u-boot.bin" is a raw binary image 1792- "u-boot" is an image in ELF binary format 1793- "u-boot.srec" is in Motorola S-Record format 1794 1795 1796Please be aware that the Makefiles assume you are using GNU make, so 1797for instance on NetBSD you might need to use "gmake" instead of 1798native "make". 1799 1800 1801If the system board that you have is not listed, then you will need 1802to port U-Boot to your hardware platform. To do this, follow these 1803steps: 1804 18051. Add a new configuration option for your board to the toplevel 1806 "Makefile" and to the "MAKEALL" script, using the existing 1807 entries as examples. Note that here and at many other places 1808 boards and other names are listed alphabetically sorted. Please 1809 keep this order. 18102. Create a new directory to hold your board specific code. Add any 1811 files you need. In your board directory, you will need at least 1812 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 18133. Create a new configuration file "include/configs/<board>.h" for 1814 your board 18153. If you're porting U-Boot to a new CPU, then also create a new 1816 directory to hold your CPU specific code. Add any files you need. 18174. Run "make <board>_config" with your new name. 18185. Type "make", and you should get a working "u-boot.srec" file 1819 to be installed on your target system. 18206. Debug and solve any problems that might arise. 1821 [Of course, this last step is much harder than it sounds.] 1822 1823 1824Testing of U-Boot Modifications, Ports to New Hardware, etc.: 1825============================================================== 1826 1827If you have modified U-Boot sources (for instance added a new board 1828or support for new devices, a new CPU, etc.) you are expected to 1829provide feedback to the other developers. The feedback normally takes 1830the form of a "patch", i. e. a context diff against a certain (latest 1831official or latest in CVS) version of U-Boot sources. 1832 1833But before you submit such a patch, please verify that your modifi- 1834cation did not break existing code. At least make sure that *ALL* of 1835the supported boards compile WITHOUT ANY compiler warnings. To do so, 1836just run the "MAKEALL" script, which will configure and build U-Boot 1837for ALL supported system. Be warned, this will take a while. You can 1838select which (cross) compiler to use py passing a `CROSS_COMPILE' 1839environment variable to the script, i. e. to use the cross tools from 1840MontaVista's Hard Hat Linux you can type 1841 1842 CROSS_COMPILE=ppc_8xx- MAKEALL 1843 1844or to build on a native PowerPC system you can type 1845 1846 CROSS_COMPILE=' ' MAKEALL 1847 1848See also "U-Boot Porting Guide" below. 1849 1850 1851 1852Monitor Commands - Overview: 1853============================ 1854 1855go - start application at address 'addr' 1856run - run commands in an environment variable 1857bootm - boot application image from memory 1858bootp - boot image via network using BootP/TFTP protocol 1859tftpboot- boot image via network using TFTP protocol 1860 and env variables "ipaddr" and "serverip" 1861 (and eventually "gatewayip") 1862rarpboot- boot image via network using RARP/TFTP protocol 1863diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 1864loads - load S-Record file over serial line 1865loadb - load binary file over serial line (kermit mode) 1866md - memory display 1867mm - memory modify (auto-incrementing) 1868nm - memory modify (constant address) 1869mw - memory write (fill) 1870cp - memory copy 1871cmp - memory compare 1872crc32 - checksum calculation 1873imd - i2c memory display 1874imm - i2c memory modify (auto-incrementing) 1875inm - i2c memory modify (constant address) 1876imw - i2c memory write (fill) 1877icrc32 - i2c checksum calculation 1878iprobe - probe to discover valid I2C chip addresses 1879iloop - infinite loop on address range 1880isdram - print SDRAM configuration information 1881sspi - SPI utility commands 1882base - print or set address offset 1883printenv- print environment variables 1884setenv - set environment variables 1885saveenv - save environment variables to persistent storage 1886protect - enable or disable FLASH write protection 1887erase - erase FLASH memory 1888flinfo - print FLASH memory information 1889bdinfo - print Board Info structure 1890iminfo - print header information for application image 1891coninfo - print console devices and informations 1892ide - IDE sub-system 1893loop - infinite loop on address range 1894mtest - simple RAM test 1895icache - enable or disable instruction cache 1896dcache - enable or disable data cache 1897reset - Perform RESET of the CPU 1898echo - echo args to console 1899version - print monitor version 1900help - print online help 1901? - alias for 'help' 1902 1903 1904Monitor Commands - Detailed Description: 1905======================================== 1906 1907TODO. 1908 1909For now: just type "help <command>". 1910 1911 1912Environment Variables: 1913====================== 1914 1915U-Boot supports user configuration using Environment Variables which 1916can be made persistent by saving to Flash memory. 1917 1918Environment Variables are set using "setenv", printed using 1919"printenv", and saved to Flash using "saveenv". Using "setenv" 1920without a value can be used to delete a variable from the 1921environment. As long as you don't save the environment you are 1922working with an in-memory copy. In case the Flash area containing the 1923environment is erased by accident, a default environment is provided. 1924 1925Some configuration options can be set using Environment Variables: 1926 1927 baudrate - see CONFIG_BAUDRATE 1928 1929 bootdelay - see CONFIG_BOOTDELAY 1930 1931 bootcmd - see CONFIG_BOOTCOMMAND 1932 1933 bootargs - Boot arguments when booting an RTOS image 1934 1935 bootfile - Name of the image to load with TFTP 1936 1937 autoload - if set to "no" (any string beginning with 'n'), 1938 "bootp" will just load perform a lookup of the 1939 configuration from the BOOTP server, but not try to 1940 load any image using TFTP 1941 1942 autostart - if set to "yes", an image loaded using the "bootp", 1943 "rarpboot", "tftpboot" or "diskboot" commands will 1944 be automatically started (by internally calling 1945 "bootm") 1946 1947 If set to "no", a standalone image passed to the 1948 "bootm" command will be copied to the load address 1949 (and eventually uncompressed), but NOT be started. 1950 This can be used to load and uncompress arbitrary 1951 data. 1952 1953 initrd_high - restrict positioning of initrd images: 1954 If this variable is not set, initrd images will be 1955 copied to the highest possible address in RAM; this 1956 is usually what you want since it allows for 1957 maximum initrd size. If for some reason you want to 1958 make sure that the initrd image is loaded below the 1959 CFG_BOOTMAPSZ limit, you can set this environment 1960 variable to a value of "no" or "off" or "0". 1961 Alternatively, you can set it to a maximum upper 1962 address to use (U-Boot will still check that it 1963 does not overwrite the U-Boot stack and data). 1964 1965 For instance, when you have a system with 16 MB 1966 RAM, and want to reseve 4 MB from use by Linux, 1967 you can do this by adding "mem=12M" to the value of 1968 the "bootargs" variable. However, now you must make 1969 sure, that the initrd image is placed in the first 1970 12 MB as well - this can be done with 1971 1972 setenv initrd_high 00c00000 1973 1974 ipaddr - IP address; needed for tftpboot command 1975 1976 loadaddr - Default load address for commands like "bootp", 1977 "rarpboot", "tftpboot", "loadb" or "diskboot" 1978 1979 loads_echo - see CONFIG_LOADS_ECHO 1980 1981 serverip - TFTP server IP address; needed for tftpboot command 1982 1983 bootretry - see CONFIG_BOOT_RETRY_TIME 1984 1985 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 1986 1987 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 1988 1989 1990The following environment variables may be used and automatically 1991updated by the network boot commands ("bootp" and "rarpboot"), 1992depending the information provided by your boot server: 1993 1994 bootfile - see above 1995 dnsip - IP address of your Domain Name Server 1996 gatewayip - IP address of the Gateway (Router) to use 1997 hostname - Target hostname 1998 ipaddr - see above 1999 netmask - Subnet Mask 2000 rootpath - Pathname of the root filesystem on the NFS server 2001 serverip - see above 2002 2003 2004There are two special Environment Variables: 2005 2006 serial# - contains hardware identification information such 2007 as type string and/or serial number 2008 ethaddr - Ethernet address 2009 2010These variables can be set only once (usually during manufacturing of 2011the board). U-Boot refuses to delete or overwrite these variables 2012once they have been set once. 2013 2014 2015Further special Environment Variables: 2016 2017 ver - Contains the U-Boot version string as printed 2018 with the "version" command. This variable is 2019 readonly (see CONFIG_VERSION_VARIABLE). 2020 2021 2022Please note that changes to some configuration parameters may take 2023only effect after the next boot (yes, that's just like Windoze :-). 2024 2025 2026Note for Redundant Ethernet Interfaces: 2027======================================= 2028 2029Some boards come with redundand ethernet interfaces; U-Boot supports 2030such configurations and is capable of automatic selection of a 2031"working" interface when needed. MAC assignemnt works as follows: 2032 2033Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2034MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2035"eth1addr" (=>eth1), "eth2addr", ... 2036 2037If the network interface stores some valid MAC address (for instance 2038in SROM), this is used as default address if there is NO correspon- 2039ding setting in the environment; if the corresponding environment 2040variable is set, this overrides the settings in the card; that means: 2041 2042o If the SROM has a valid MAC address, and there is no address in the 2043 environment, the SROM's address is used. 2044 2045o If there is no valid address in the SROM, and a definition in the 2046 environment exists, then the value from the environment variable is 2047 used. 2048 2049o If both the SROM and the environment contain a MAC address, and 2050 both addresses are the same, this MAC address is used. 2051 2052o If both the SROM and the environment contain a MAC address, and the 2053 addresses differ, the value from the environment is used and a 2054 warning is printed. 2055 2056o If neither SROM nor the environment contain a MAC address, an error 2057 is raised. 2058 2059 2060 2061Image Formats: 2062============== 2063 2064The "boot" commands of this monitor operate on "image" files which 2065can be basicly anything, preceeded by a special header; see the 2066definitions in include/image.h for details; basicly, the header 2067defines the following image properties: 2068 2069* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2070 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2071 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2072 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS). 2073* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86, 2074 IA64, MIPS, MIPS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 2075 Currently supported: PowerPC). 2076* Compression Type (Provisions for uncompressed, gzip, bzip2; 2077 Currently supported: uncompressed, gzip). 2078* Load Address 2079* Entry Point 2080* Image Name 2081* Image Timestamp 2082 2083The header is marked by a special Magic Number, and both the header 2084and the data portions of the image are secured against corruption by 2085CRC32 checksums. 2086 2087 2088Linux Support: 2089============== 2090 2091Although U-Boot should support any OS or standalone application 2092easily, Linux has always been in the focus during the design of 2093U-Boot. 2094 2095U-Boot includes many features that so far have been part of some 2096special "boot loader" code within the Linux kernel. Also, any 2097"initrd" images to be used are no longer part of one big Linux image; 2098instead, kernel and "initrd" are separate images. This implementation 2099serves serveral purposes: 2100 2101- the same features can be used for other OS or standalone 2102 applications (for instance: using compressed images to reduce the 2103 Flash memory footprint) 2104 2105- it becomes much easier to port new Linux kernel versions because 2106 lots of low-level, hardware dependend stuff are done by U-Boot 2107 2108- the same Linux kernel image can now be used with different "initrd" 2109 images; of course this also means that different kernel images can 2110 be run with the same "initrd". This makes testing easier (you don't 2111 have to build a new "zImage.initrd" Linux image when you just 2112 change a file in your "initrd"). Also, a field-upgrade of the 2113 software is easier now. 2114 2115 2116Linux HOWTO: 2117============ 2118 2119Porting Linux to U-Boot based systems: 2120--------------------------------------- 2121 2122U-Boot cannot save you from doing all the necessary modifications to 2123configure the Linux device drivers for use with your target hardware 2124(no, we don't intend to provide a full virtual machine interface to 2125Linux :-). 2126 2127But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 2128 2129Just make sure your machine specific header file (for instance 2130include/asm-ppc/tqm8xx.h) includes the same definition of the Board 2131Information structure as we define in include/u-boot.h, and make 2132sure that your definition of IMAP_ADDR uses the same value as your 2133U-Boot configuration in CFG_IMMR. 2134 2135 2136Configuring the Linux kernel: 2137----------------------------- 2138 2139No specific requirements for U-Boot. Make sure you have some root 2140device (initial ramdisk, NFS) for your target system. 2141 2142 2143Building a Linux Image: 2144----------------------- 2145 2146With U-Boot, "normal" build targets like "zImage" or "bzImage" are 2147not used. If you use recent kernel source, a new build target 2148"uImage" will exist which automatically builds an image usable by 2149U-Boot. Most older kernels also have support for a "pImage" target, 2150which was introduced for our predecessor project PPCBoot and uses a 2151100% compatible format. 2152 2153Example: 2154 2155 make TQM850L_config 2156 make oldconfig 2157 make dep 2158 make uImage 2159 2160The "uImage" build target uses a special tool (in 'tools/mkimage') to 2161encapsulate a compressed Linux kernel image with header information, 2162CRC32 checksum etc. for use with U-Boot. This is what we are doing: 2163 2164* build a standard "vmlinux" kernel image (in ELF binary format): 2165 2166* convert the kernel into a raw binary image: 2167 2168 ${CROSS_COMPILE}-objcopy -O binary \ 2169 -R .note -R .comment \ 2170 -S vmlinux linux.bin 2171 2172* compress the binary image: 2173 2174 gzip -9 linux.bin 2175 2176* package compressed binary image for U-Boot: 2177 2178 mkimage -A ppc -O linux -T kernel -C gzip \ 2179 -a 0 -e 0 -n "Linux Kernel Image" \ 2180 -d linux.bin.gz uImage 2181 2182 2183The "mkimage" tool can also be used to create ramdisk images for use 2184with U-Boot, either separated from the Linux kernel image, or 2185combined into one file. "mkimage" encapsulates the images with a 64 2186byte header containing information about target architecture, 2187operating system, image type, compression method, entry points, time 2188stamp, CRC32 checksums, etc. 2189 2190"mkimage" can be called in two ways: to verify existing images and 2191print the header information, or to build new images. 2192 2193In the first form (with "-l" option) mkimage lists the information 2194contained in the header of an existing U-Boot image; this includes 2195checksum verification: 2196 2197 tools/mkimage -l image 2198 -l ==> list image header information 2199 2200The second form (with "-d" option) is used to build a U-Boot image 2201from a "data file" which is used as image payload: 2202 2203 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 2204 -n name -d data_file image 2205 -A ==> set architecture to 'arch' 2206 -O ==> set operating system to 'os' 2207 -T ==> set image type to 'type' 2208 -C ==> set compression type 'comp' 2209 -a ==> set load address to 'addr' (hex) 2210 -e ==> set entry point to 'ep' (hex) 2211 -n ==> set image name to 'name' 2212 -d ==> use image data from 'datafile' 2213 2214Right now, all Linux kernels use the same load address (0x00000000), 2215but the entry point address depends on the kernel version: 2216 2217- 2.2.x kernels have the entry point at 0x0000000C, 2218- 2.3.x and later kernels have the entry point at 0x00000000. 2219 2220So a typical call to build a U-Boot image would read: 2221 2222 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2223 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 2224 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 2225 > examples/uImage.TQM850L 2226 Image Name: 2.4.4 kernel for TQM850L 2227 Created: Wed Jul 19 02:34:59 2000 2228 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2229 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2230 Load Address: 0x00000000 2231 Entry Point: 0x00000000 2232 2233To verify the contents of the image (or check for corruption): 2234 2235 -> tools/mkimage -l examples/uImage.TQM850L 2236 Image Name: 2.4.4 kernel for TQM850L 2237 Created: Wed Jul 19 02:34:59 2000 2238 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2239 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2240 Load Address: 0x00000000 2241 Entry Point: 0x00000000 2242 2243NOTE: for embedded systems where boot time is critical you can trade 2244speed for memory and install an UNCOMPRESSED image instead: this 2245needs more space in Flash, but boots much faster since it does not 2246need to be uncompressed: 2247 2248 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 2249 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2250 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 2251 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 2252 > examples/uImage.TQM850L-uncompressed 2253 Image Name: 2.4.4 kernel for TQM850L 2254 Created: Wed Jul 19 02:34:59 2000 2255 Image Type: PowerPC Linux Kernel Image (uncompressed) 2256 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 2257 Load Address: 0x00000000 2258 Entry Point: 0x00000000 2259 2260 2261Similar you can build U-Boot images from a 'ramdisk.image.gz' file 2262when your kernel is intended to use an initial ramdisk: 2263 2264 -> tools/mkimage -n 'Simple Ramdisk Image' \ 2265 > -A ppc -O linux -T ramdisk -C gzip \ 2266 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 2267 Image Name: Simple Ramdisk Image 2268 Created: Wed Jan 12 14:01:50 2000 2269 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2270 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 2271 Load Address: 0x00000000 2272 Entry Point: 0x00000000 2273 2274 2275Installing a Linux Image: 2276------------------------- 2277 2278To downloading a U-Boot image over the serial (console) interface, 2279you must convert the image to S-Record format: 2280 2281 objcopy -I binary -O srec examples/image examples/image.srec 2282 2283The 'objcopy' does not understand the information in the U-Boot 2284image header, so the resulting S-Record file will be relative to 2285address 0x00000000. To load it to a given address, you need to 2286specify the target address as 'offset' parameter with the 'loads' 2287command. 2288 2289Example: install the image to address 0x40100000 (which on the 2290TQM8xxL is in the first Flash bank): 2291 2292 => erase 40100000 401FFFFF 2293 2294 .......... done 2295 Erased 8 sectors 2296 2297 => loads 40100000 2298 ## Ready for S-Record download ... 2299 ~>examples/image.srec 2300 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 2301 ... 2302 15989 15990 15991 15992 2303 [file transfer complete] 2304 [connected] 2305 ## Start Addr = 0x00000000 2306 2307 2308You can check the success of the download using the 'iminfo' command; 2309this includes a checksum verification so you can be sure no data 2310corruption happened: 2311 2312 => imi 40100000 2313 2314 ## Checking Image at 40100000 ... 2315 Image Name: 2.2.13 for initrd on TQM850L 2316 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2317 Data Size: 335725 Bytes = 327 kB = 0 MB 2318 Load Address: 00000000 2319 Entry Point: 0000000c 2320 Verifying Checksum ... OK 2321 2322 2323 2324Boot Linux: 2325----------- 2326 2327The "bootm" command is used to boot an application that is stored in 2328memory (RAM or Flash). In case of a Linux kernel image, the contents 2329of the "bootargs" environment variable is passed to the kernel as 2330parameters. You can check and modify this variable using the 2331"printenv" and "setenv" commands: 2332 2333 2334 => printenv bootargs 2335 bootargs=root=/dev/ram 2336 2337 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2338 2339 => printenv bootargs 2340 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2341 2342 => bootm 40020000 2343 ## Booting Linux kernel at 40020000 ... 2344 Image Name: 2.2.13 for NFS on TQM850L 2345 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2346 Data Size: 381681 Bytes = 372 kB = 0 MB 2347 Load Address: 00000000 2348 Entry Point: 0000000c 2349 Verifying Checksum ... OK 2350 Uncompressing Kernel Image ... OK 2351 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 2352 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2353 time_init: decrementer frequency = 187500000/60 2354 Calibrating delay loop... 49.77 BogoMIPS 2355 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 2356 ... 2357 2358If you want to boot a Linux kernel with initial ram disk, you pass 2359the memory addreses of both the kernel and the initrd image (PPBCOOT 2360format!) to the "bootm" command: 2361 2362 => imi 40100000 40200000 2363 2364 ## Checking Image at 40100000 ... 2365 Image Name: 2.2.13 for initrd on TQM850L 2366 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2367 Data Size: 335725 Bytes = 327 kB = 0 MB 2368 Load Address: 00000000 2369 Entry Point: 0000000c 2370 Verifying Checksum ... OK 2371 2372 ## Checking Image at 40200000 ... 2373 Image Name: Simple Ramdisk Image 2374 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2375 Data Size: 566530 Bytes = 553 kB = 0 MB 2376 Load Address: 00000000 2377 Entry Point: 00000000 2378 Verifying Checksum ... OK 2379 2380 => bootm 40100000 40200000 2381 ## Booting Linux kernel at 40100000 ... 2382 Image Name: 2.2.13 for initrd on TQM850L 2383 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2384 Data Size: 335725 Bytes = 327 kB = 0 MB 2385 Load Address: 00000000 2386 Entry Point: 0000000c 2387 Verifying Checksum ... OK 2388 Uncompressing Kernel Image ... OK 2389 ## Loading RAMDisk Image at 40200000 ... 2390 Image Name: Simple Ramdisk Image 2391 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2392 Data Size: 566530 Bytes = 553 kB = 0 MB 2393 Load Address: 00000000 2394 Entry Point: 00000000 2395 Verifying Checksum ... OK 2396 Loading Ramdisk ... OK 2397 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 2398 Boot arguments: root=/dev/ram 2399 time_init: decrementer frequency = 187500000/60 2400 Calibrating delay loop... 49.77 BogoMIPS 2401 ... 2402 RAMDISK: Compressed image found at block 0 2403 VFS: Mounted root (ext2 filesystem). 2404 2405 bash# 2406 2407More About U-Boot Image Types: 2408------------------------------ 2409 2410U-Boot supports the following image types: 2411 2412 "Standalone Programs" are directly runnable in the environment 2413 provided by U-Boot; it is expected that (if they behave 2414 well) you can continue to work in U-Boot after return from 2415 the Standalone Program. 2416 "OS Kernel Images" are usually images of some Embedded OS which 2417 will take over control completely. Usually these programs 2418 will install their own set of exception handlers, device 2419 drivers, set up the MMU, etc. - this means, that you cannot 2420 expect to re-enter U-Boot except by resetting the CPU. 2421 "RAMDisk Images" are more or less just data blocks, and their 2422 parameters (address, size) are passed to an OS kernel that is 2423 being started. 2424 "Multi-File Images" contain several images, typically an OS 2425 (Linux) kernel image and one or more data images like 2426 RAMDisks. This construct is useful for instance when you want 2427 to boot over the network using BOOTP etc., where the boot 2428 server provides just a single image file, but you want to get 2429 for instance an OS kernel and a RAMDisk image. 2430 2431 "Multi-File Images" start with a list of image sizes, each 2432 image size (in bytes) specified by an "uint32_t" in network 2433 byte order. This list is terminated by an "(uint32_t)0". 2434 Immediately after the terminating 0 follow the images, one by 2435 one, all aligned on "uint32_t" boundaries (size rounded up to 2436 a multiple of 4 bytes). 2437 2438 "Firmware Images" are binary images containing firmware (like 2439 U-Boot or FPGA images) which usually will be programmed to 2440 flash memory. 2441 2442 "Script files" are command sequences that will be executed by 2443 U-Boot's command interpreter; this feature is especially 2444 useful when you configure U-Boot to use a real shell (hush) 2445 as command interpreter. 2446 2447 2448Standalone HOWTO: 2449================= 2450 2451One of the features of U-Boot is that you can dynamically load and 2452run "standalone" applications, which can use some resources of 2453U-Boot like console I/O functions or interrupt services. 2454 2455Two simple examples are included with the sources: 2456 2457"Hello World" Demo: 2458------------------- 2459 2460'examples/hello_world.c' contains a small "Hello World" Demo 2461application; it is automatically compiled when you build U-Boot. 2462It's configured to run at address 0x00040004, so you can play with it 2463like that: 2464 2465 => loads 2466 ## Ready for S-Record download ... 2467 ~>examples/hello_world.srec 2468 1 2 3 4 5 6 7 8 9 10 11 ... 2469 [file transfer complete] 2470 [connected] 2471 ## Start Addr = 0x00040004 2472 2473 => go 40004 Hello World! This is a test. 2474 ## Starting application at 0x00040004 ... 2475 Hello World 2476 argc = 7 2477 argv[0] = "40004" 2478 argv[1] = "Hello" 2479 argv[2] = "World!" 2480 argv[3] = "This" 2481 argv[4] = "is" 2482 argv[5] = "a" 2483 argv[6] = "test." 2484 argv[7] = "<NULL>" 2485 Hit any key to exit ... 2486 2487 ## Application terminated, rc = 0x0 2488 2489Another example, which demonstrates how to register a CPM interrupt 2490handler with the U-Boot code, can be found in 'examples/timer.c'. 2491Here, a CPM timer is set up to generate an interrupt every second. 2492The interrupt service routine is trivial, just printing a '.' 2493character, but this is just a demo program. The application can be 2494controlled by the following keys: 2495 2496 ? - print current values og the CPM Timer registers 2497 b - enable interrupts and start timer 2498 e - stop timer and disable interrupts 2499 q - quit application 2500 2501 => loads 2502 ## Ready for S-Record download ... 2503 ~>examples/timer.srec 2504 1 2 3 4 5 6 7 8 9 10 11 ... 2505 [file transfer complete] 2506 [connected] 2507 ## Start Addr = 0x00040004 2508 2509 => go 40004 2510 ## Starting application at 0x00040004 ... 2511 TIMERS=0xfff00980 2512 Using timer 1 2513 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 2514 2515Hit 'b': 2516 [q, b, e, ?] Set interval 1000000 us 2517 Enabling timer 2518Hit '?': 2519 [q, b, e, ?] ........ 2520 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 2521Hit '?': 2522 [q, b, e, ?] . 2523 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 2524Hit '?': 2525 [q, b, e, ?] . 2526 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 2527Hit '?': 2528 [q, b, e, ?] . 2529 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 2530Hit 'e': 2531 [q, b, e, ?] ...Stopping timer 2532Hit 'q': 2533 [q, b, e, ?] ## Application terminated, rc = 0x0 2534 2535 2536 2537Minicom warning: 2538================ 2539 2540Over time, many people have reported problems when trying to used the 2541"minicom" terminal emulation program for serial download. I (wd) 2542consider minicom to be broken, and recommend not to use it. Under 2543Unix, I recommend to use CKermit for general purpose use (and 2544especially for kermit binary protocol download ("loadb" command), and 2545use "cu" for S-Record download ("loads" command). 2546 2547NetBSD Notes: 2548============= 2549 2550Starting at version 0.9.2, U-Boot supports NetBSD both as host 2551(build U-Boot) and target system (boots NetBSD/mpc8xx). 2552 2553Building requires a cross environment; it is known to work on 2554NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 2555need gmake since the Makefiles are not compatible with BSD make). 2556Note that the cross-powerpc package does not install include files; 2557attempting to build U-Boot will fail because <machine/ansi.h> is 2558missing. This file has to be installed and patched manually: 2559 2560 # cd /usr/pkg/cross/powerpc-netbsd/include 2561 # mkdir powerpc 2562 # ln -s powerpc machine 2563 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 2564 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 2565 2566Native builds *don't* work due to incompatibilities between native 2567and U-Boot include files. 2568 2569Booting assumes that (the first part of) the image booted is a 2570stage-2 loader which in turn loads and then invokes the kernel 2571proper. Loader sources will eventually appear in the NetBSD source 2572tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 2573meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for 2574details. 2575 2576 2577Implementation Internals: 2578========================= 2579 2580The following is not intended to be a complete description of every 2581implementation detail. However, it should help to understand the 2582inner workings of U-Boot and make it easier to port it to custom 2583hardware. 2584 2585 2586Initial Stack, Global Data: 2587--------------------------- 2588 2589The implementation of U-Boot is complicated by the fact that U-Boot 2590starts running out of ROM (flash memory), usually without access to 2591system RAM (because the memory controller is not initialized yet). 2592This means that we don't have writable Data or BSS segments, and BSS 2593is not initialized as zero. To be able to get a C environment working 2594at all, we have to allocate at least a minimal stack. Implementation 2595options for this are defined and restricted by the CPU used: Some CPU 2596models provide on-chip memory (like the IMMR area on MPC8xx and 2597MPC826x processors), on others (parts of) the data cache can be 2598locked as (mis-) used as memory, etc. 2599 2600 Chris Hallinan posted a good summy of these issues to the 2601 u-boot-users mailing list: 2602 2603 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 2604 From: "Chris Hallinan" <clh@net1plus.com> 2605 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 2606 ... 2607 2608 Correct me if I'm wrong, folks, but the way I understand it 2609 is this: Using DCACHE as initial RAM for Stack, etc, does not 2610 require any physical RAM backing up the cache. The cleverness 2611 is that the cache is being used as a temporary supply of 2612 necessary storage before the SDRAM controller is setup. It's 2613 beyond the scope of this list to expain the details, but you 2614 can see how this works by studying the cache architecture and 2615 operation in the architecture and processor-specific manuals. 2616 2617 OCM is On Chip Memory, which I believe the 405GP has 4K. It 2618 is another option for the system designer to use as an 2619 initial stack/ram area prior to SDRAM being available. Either 2620 option should work for you. Using CS 4 should be fine if your 2621 board designers haven't used it for something that would 2622 cause you grief during the initial boot! It is frequently not 2623 used. 2624 2625 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 2626 with your processor/board/system design. The default value 2627 you will find in any recent u-boot distribution in 2628 Walnut405.h should work for you. I'd set it to a value larger 2629 than your SDRAM module. If you have a 64MB SDRAM module, set 2630 it above 400_0000. Just make sure your board has no resources 2631 that are supposed to respond to that address! That code in 2632 start.S has been around a while and should work as is when 2633 you get the config right. 2634 2635 -Chris Hallinan 2636 DS4.COM, Inc. 2637 2638It is essential to remember this, since it has some impact on the C 2639code for the initialization procedures: 2640 2641* Initialized global data (data segment) is read-only. Do not attempt 2642 to write it. 2643 2644* Do not use any unitialized global data (or implicitely initialized 2645 as zero data - BSS segment) at all - this is undefined, initiali- 2646 zation is performed later (when relocationg to RAM). 2647 2648* Stack space is very limited. Avoid big data buffers or things like 2649 that. 2650 2651Having only the stack as writable memory limits means we cannot use 2652normal global data to share information beween the code. But it 2653turned out that the implementation of U-Boot can be greatly 2654simplified by making a global data structure (gd_t) available to all 2655functions. We could pass a pointer to this data as argument to _all_ 2656functions, but this would bloat the code. Instead we use a feature of 2657the GCC compiler (Global Register Variables) to share the data: we 2658place a pointer (gd) to the global data into a register which we 2659reserve for this purpose. 2660 2661When chosing a register for such a purpose we are restricted by the 2662relevant (E)ABI specifications for the current architecture, and by 2663GCC's implementation. 2664 2665For PowerPC, the following registers have specific use: 2666 R1: stack pointer 2667 R2: TOC pointer 2668 R3-R4: parameter passing and return values 2669 R5-R10: parameter passing 2670 R13: small data area pointer 2671 R30: GOT pointer 2672 R31: frame pointer 2673 2674 (U-Boot also uses R14 as internal GOT pointer.) 2675 2676 ==> U-Boot will use R29 to hold a pointer to the global data 2677 2678 Note: on PPC, we could use a static initializer (since the 2679 address of the global data structure is known at compile time), 2680 but it turned out that reserving a register results in somewhat 2681 smaller code - although the code savings are not that big (on 2682 average for all boards 752 bytes for the whole U-Boot image, 2683 624 text + 127 data). 2684 2685On ARM, the following registers are used: 2686 2687 R0: function argument word/integer result 2688 R1-R3: function argument word 2689 R9: GOT pointer 2690 R10: stack limit (used only if stack checking if enabled) 2691 R11: argument (frame) pointer 2692 R12: temporary workspace 2693 R13: stack pointer 2694 R14: link register 2695 R15: program counter 2696 2697 ==> U-Boot will use R8 to hold a pointer to the global data 2698 2699 2700 2701Memory Management: 2702------------------ 2703 2704U-Boot runs in system state and uses physical addresses, i.e. the 2705MMU is not used either for address mapping nor for memory protection. 2706 2707The available memory is mapped to fixed addresses using the memory 2708controller. In this process, a contiguous block is formed for each 2709memory type (Flash, SDRAM, SRAM), even when it consists of several 2710physical memory banks. 2711 2712U-Boot is installed in the first 128 kB of the first Flash bank (on 2713TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 2714booting and sizing and initializing DRAM, the code relocates itself 2715to the upper end of DRAM. Immediately below the U-Boot code some 2716memory is reserved for use by malloc() [see CFG_MALLOC_LEN 2717configuration setting]. Below that, a structure with global Board 2718Info data is placed, followed by the stack (growing downward). 2719 2720Additionally, some exception handler code is copied to the low 8 kB 2721of DRAM (0x00000000 ... 0x00001FFF). 2722 2723So a typical memory configuration with 16 MB of DRAM could look like 2724this: 2725 2726 0x0000 0000 Exception Vector code 2727 : 2728 0x0000 1FFF 2729 0x0000 2000 Free for Application Use 2730 : 2731 : 2732 2733 : 2734 : 2735 0x00FB FF20 Monitor Stack (Growing downward) 2736 0x00FB FFAC Board Info Data and permanent copy of global data 2737 0x00FC 0000 Malloc Arena 2738 : 2739 0x00FD FFFF 2740 0x00FE 0000 RAM Copy of Monitor Code 2741 ... eventually: LCD or video framebuffer 2742 ... eventually: pRAM (Protected RAM - unchanged by reset) 2743 0x00FF FFFF [End of RAM] 2744 2745 2746System Initialization: 2747---------------------- 2748 2749In the reset configuration, U-Boot starts at the reset entry point 2750(on most PowerPC systens at address 0x00000100). Because of the reset 2751configuration for CS0# this is a mirror of the onboard Flash memory. 2752To be able to re-map memory U-Boot then jumps to it's link address. 2753To be able to implement the initialization code in C, a (small!) 2754initial stack is set up in the internal Dual Ported RAM (in case CPUs 2755which provide such a feature like MPC8xx or MPC8260), or in a locked 2756part of the data cache. After that, U-Boot initializes the CPU core, 2757the caches and the SIU. 2758 2759Next, all (potentially) available memory banks are mapped using a 2760preliminary mapping. For example, we put them on 512 MB boundaries 2761(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 2762on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 2763programmed for SDRAM access. Using the temporary configuration, a 2764simple memory test is run that determines the size of the SDRAM 2765banks. 2766 2767When there is more than one SDRAM bank, and the banks are of 2768different size, the larger is mapped first. For equal size, the first 2769bank (CS2#) is mapped first. The first mapping is always for address 27700x00000000, with any additional banks following immediately to create 2771contiguous memory starting from 0. 2772 2773Then, the monitor installs itself at the upper end of the SDRAM area 2774and allocates memory for use by malloc() and for the global Board 2775Info data; also, the exception vector code is copied to the low RAM 2776pages, and the final stack is set up. 2777 2778Only after this relocation will you have a "normal" C environment; 2779until that you are restricted in several ways, mostly because you are 2780running from ROM, and because the code will have to be relocated to a 2781new address in RAM. 2782 2783 2784U-Boot Porting Guide: 2785---------------------- 2786 2787[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 2788list, October 2002] 2789 2790 2791int main (int argc, char *argv[]) 2792{ 2793 sighandler_t no_more_time; 2794 2795 signal (SIGALRM, no_more_time); 2796 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 2797 2798 if (available_money > available_manpower) { 2799 pay consultant to port U-Boot; 2800 return 0; 2801 } 2802 2803 Download latest U-Boot source; 2804 2805 Subscribe to u-boot-users mailing list; 2806 2807 if (clueless) { 2808 email ("Hi, I am new to U-Boot, how do I get started?"); 2809 } 2810 2811 while (learning) { 2812 Read the README file in the top level directory; 2813 Read http://www.denx.de/re/DPLG.html 2814 Read the source, Luke; 2815 } 2816 2817 if (available_money > toLocalCurrency ($2500)) { 2818 Buy a BDI2000; 2819 } else { 2820 Add a lot of aggravation and time; 2821 } 2822 2823 Create your own board support subdirectory; 2824 2825 Create your own board config file; 2826 2827 while (!running) { 2828 do { 2829 Add / modify source code; 2830 } until (compiles); 2831 Debug; 2832 if (clueless) 2833 email ("Hi, I am having problems..."); 2834 } 2835 Send patch file to Wolfgang; 2836 2837 return 0; 2838} 2839 2840void no_more_time (int sig) 2841{ 2842 hire_a_guru(); 2843} 2844 2845 2846 2847Coding Standards: 2848----------------- 2849 2850All contributions to U-Boot should conform to the Linux kernel 2851coding style; see the file "Documentation/CodingStyle" in your Linux 2852kernel source directory. 2853 2854Please note that U-Boot is implemented in C (and to some small parts 2855in Assembler); no C++ is used, so please do not use C++ style 2856comments (//) in your code. 2857 2858Submissions which do not conform to the standards may be returned 2859with a request to reformat the changes. 2860 2861 2862Submitting Patches: 2863------------------- 2864 2865Since the number of patches for U-Boot is growing, we need to 2866establish some rules. Submissions which do not conform to these rules 2867may be rejected, even when they contain important and valuable stuff. 2868 2869 2870When you send a patch, please include the following information with 2871it: 2872 2873* For bug fixes: a description of the bug and how your patch fixes 2874 this bug. Please try to include a way of demonstrating that the 2875 patch actually fixes something. 2876 2877* For new features: a description of the feature and your 2878 implementation. 2879 2880* A CHANGELOG entry as plaintext (separate from the patch) 2881 2882* For major contributions, your entry to the CREDITS file 2883 2884* When you add support for a new board, don't forget to add this 2885 board to the MAKEALL script, too. 2886 2887* If your patch adds new configuration options, don't forget to 2888 document these in the README file. 2889 2890* The patch itself. If you are accessing the CVS repository use "cvs 2891 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your 2892 version of diff does not support these options, then get the latest 2893 version of GNU diff. 2894 2895 We accept patches as plain text, MIME attachments or as uuencoded 2896 gzipped text. 2897 2898Notes: 2899 2900* Before sending the patch, run the MAKEALL script on your patched 2901 source tree and make sure that no errors or warnings are reported 2902 for any of the boards. 2903 2904* Keep your modifications to the necessary minimum: A patch 2905 containing several unrelated changes or arbitrary reformats will be 2906 returned with a request to re-formatting / split it. 2907 2908* If you modify existing code, make sure that your new code does not 2909 add to the memory footprint of the code ;-) Small is beautiful! 2910 When adding new features, these should compile conditionally only 2911 (using #ifdef), and the resulting code with the new feature 2912 disabled must not need more memory than the old code without your 2913 modification. 2914