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 dependent files 123- common Misc architecture independent functions 124- cpu CPU specific files 125- disk Code for disk drive partition handling 126- doc Documentation (don't expect too much) 127- drivers Commonly 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/arm925t Files specific to ARM 925 CPUs 144- cpu/arm926ejs Files specific to ARM 926 CPUs 145- cpu/mpc5xx Files specific to Motorola MPC5xx CPUs 146- cpu/mpc8xx Files specific to Motorola MPC8xx CPUs 147- cpu/mpc824x Files specific to Motorola MPC824x CPUs 148- cpu/mpc8260 Files specific to Motorola MPC8260 CPU 149- cpu/ppc4xx Files specific to IBM 4xx CPUs 150 151 152- board/LEOX/ Files specific to boards manufactured by The LEOX team 153- board/LEOX/elpt860 Files specific to ELPT860 boards 154- board/RPXClassic 155 Files specific to RPXClassic boards 156- board/RPXlite Files specific to RPXlite boards 157- board/at91rm9200dk Files specific to AT91RM9200DK boards 158- board/c2mon Files specific to c2mon boards 159- board/cmi Files specific to cmi boards 160- board/cogent Files specific to Cogent boards 161 (need further configuration) 162 Files specific to CPCIISER4 boards 163- board/cpu86 Files specific to CPU86 boards 164- board/cray/ Files specific to boards manufactured by Cray 165- board/cray/L1 Files specific to L1 boards 166- board/cu824 Files specific to CU824 boards 167- board/ebony Files specific to IBM Ebony board 168- board/eric Files specific to ERIC boards 169- board/esd/ Files specific to boards manufactured by ESD 170- board/esd/adciop Files specific to ADCIOP boards 171- board/esd/ar405 Files specific to AR405 boards 172- board/esd/canbt Files specific to CANBT boards 173- board/esd/cpci405 Files specific to CPCI405 boards 174- board/esd/cpciiser4 Files specific to CPCIISER4 boards 175- board/esd/common Common files for ESD boards 176- board/esd/dasa_sim Files specific to DASA_SIM boards 177- board/esd/du405 Files specific to DU405 boards 178- board/esd/ocrtc Files specific to OCRTC boards 179- board/esd/pci405 Files specific to PCI405 boards 180- board/esteem192e 181 Files specific to ESTEEM192E boards 182- board/etx094 Files specific to ETX_094 boards 183- board/evb64260 184 Files specific to EVB64260 boards 185- board/fads Files specific to FADS boards 186- board/flagadm Files specific to FLAGADM boards 187- board/gen860t Files specific to GEN860T and GEN860T_SC boards 188- board/genietv Files specific to GENIETV boards 189- board/gth Files specific to GTH boards 190- board/hermes Files specific to HERMES boards 191- board/hymod Files specific to HYMOD boards 192- board/icu862 Files specific to ICU862 boards 193- board/ip860 Files specific to IP860 boards 194- board/iphase4539 195 Files specific to Interphase4539 boards 196- board/ivm Files specific to IVMS8/IVML24 boards 197- board/lantec Files specific to LANTEC boards 198- board/lwmon Files specific to LWMON boards 199- board/mbx8xx Files specific to MBX boards 200- board/mpc8260ads 201 Files specific to MPC8260ADS and PQ2FADS-ZU boards 202- board/mpl/ Files specific to boards manufactured by MPL 203- board/mpl/common Common files for MPL boards 204- board/mpl/pip405 Files specific to PIP405 boards 205- board/mpl/mip405 Files specific to MIP405 boards 206- board/mpl/vcma9 Files specific to VCMA9 boards 207- board/musenki Files specific to MUSEKNI boards 208- board/mvs1 Files specific to MVS1 boards 209- board/nx823 Files specific to NX823 boards 210- board/oxc Files specific to OXC boards 211- board/omap1510inn 212 Files specific to OMAP 1510 Innovator boards 213- board/omap1610inn 214 Files specific to OMAP 1610 Innovator boards 215- board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards 216- board/pm826 Files specific to PM826 boards 217- board/ppmc8260 218 Files specific to PPMC8260 boards 219- board/rpxsuper 220 Files specific to RPXsuper boards 221- board/rsdproto 222 Files specific to RSDproto boards 223- board/sandpoint 224 Files specific to Sandpoint boards 225- board/sbc8260 Files specific to SBC8260 boards 226- board/sacsng Files specific to SACSng boards 227- board/siemens Files specific to boards manufactured by Siemens AG 228- board/siemens/CCM Files specific to CCM boards 229- board/siemens/IAD210 Files specific to IAD210 boards 230- board/siemens/SCM Files specific to SCM boards 231- board/siemens/pcu_e Files specific to PCU_E boards 232- board/sixnet Files specific to SIXNET boards 233- board/spd8xx Files specific to SPD8xxTS boards 234- board/tqm8260 Files specific to TQM8260 boards 235- board/tqm8xx Files specific to TQM8xxL boards 236- board/w7o Files specific to W7O boards 237- board/walnut405 238 Files specific to Walnut405 boards 239- board/westel/ Files specific to boards manufactured by Westel Wireless 240- board/westel/amx860 Files specific to AMX860 boards 241- board/utx8245 Files specific to UTX8245 boards 242 243Software Configuration: 244======================= 245 246Configuration is usually done using C preprocessor defines; the 247rationale behind that is to avoid dead code whenever possible. 248 249There are two classes of configuration variables: 250 251* Configuration _OPTIONS_: 252 These are selectable by the user and have names beginning with 253 "CONFIG_". 254 255* Configuration _SETTINGS_: 256 These depend on the hardware etc. and should not be meddled with if 257 you don't know what you're doing; they have names beginning with 258 "CFG_". 259 260Later we will add a configuration tool - probably similar to or even 261identical to what's used for the Linux kernel. Right now, we have to 262do the configuration by hand, which means creating some symbolic 263links and editing some configuration files. We use the TQM8xxL boards 264as an example here. 265 266 267Selection of Processor Architecture and Board Type: 268--------------------------------------------------- 269 270For all supported boards there are ready-to-use default 271configurations available; just type "make <board_name>_config". 272 273Example: For a TQM823L module type: 274 275 cd u-boot 276 make TQM823L_config 277 278For the Cogent platform, you need to specify the cpu type as well; 279e.g. "make cogent_mpc8xx_config". And also configure the cogent 280directory according to the instructions in cogent/README. 281 282 283Configuration Options: 284---------------------- 285 286Configuration depends on the combination of board and CPU type; all 287such information is kept in a configuration file 288"include/configs/<board_name>.h". 289 290Example: For a TQM823L module, all configuration settings are in 291"include/configs/TQM823L.h". 292 293 294Many of the options are named exactly as the corresponding Linux 295kernel configuration options. The intention is to make it easier to 296build a config tool - later. 297 298 299The following options need to be configured: 300 301- CPU Type: Define exactly one of 302 303 PowerPC based CPUs: 304 ------------------- 305 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860 306 or CONFIG_MPC5xx 307 or CONFIG_MPC824X, CONFIG_MPC8260 308 or CONFIG_IOP480 309 or CONFIG_405GP 310 or CONFIG_405EP 311 or CONFIG_440 312 or CONFIG_MPC74xx 313 or CONFIG_750FX 314 315 ARM based CPUs: 316 --------------- 317 CONFIG_SA1110 318 CONFIG_ARM7 319 CONFIG_PXA250 320 321 322- Board Type: Define exactly one of 323 324 PowerPC based boards: 325 --------------------- 326 327 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper, 328 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850, 329 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS, 330 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T, 331 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240, 332 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245, 333 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L, 334 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L, 335 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L, 336 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L, 337 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260, 338 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech, 339 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245, 340 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC, 341 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG, 342 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405, 343 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA, 344 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon, 345 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260, 346 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx, 347 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260, 348 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260, 349 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes, 350 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod, 351 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon, 352 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e, 353 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260, 354 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto, 355 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260, 356 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L, 357 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI, 358 CONFIG_NETVIA, CONFIG_RBC823 359 360 ARM based boards: 361 ----------------- 362 363 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312, 364 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK, 365 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610 366 CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410, 367 CONFIG_TRAB, CONFIG_VCMA9, CONFIG_AT91RM9200DK 368 369 370- CPU Module Type: (if CONFIG_COGENT is defined) 371 Define exactly one of 372 CONFIG_CMA286_60_OLD 373--- FIXME --- not tested yet: 374 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 375 CONFIG_CMA287_23, CONFIG_CMA287_50 376 377- Motherboard Type: (if CONFIG_COGENT is defined) 378 Define exactly one of 379 CONFIG_CMA101, CONFIG_CMA102 380 381- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 382 Define one or more of 383 CONFIG_CMA302 384 385- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 386 Define one or more of 387 CONFIG_LCD_HEARTBEAT - update a character position on 388 the lcd display every second with 389 a "rotator" |\-/|\-/ 390 391- Board flavour: (if CONFIG_MPC8260ADS is defined) 392 CONFIG_ADSTYPE 393 Possible values are: 394 CFG_8260ADS - original MPC8260ADS 395 CFG_8266ADS - MPC8266ADS (untested) 396 CFG_PQ2FADS - PQ2FADS-ZU 397 398 399- MPC824X Family Member (if CONFIG_MPC824X is defined) 400 Define exactly one of 401 CONFIG_MPC8240, CONFIG_MPC8245 402 403- 8xx CPU Options: (if using an 8xx cpu) 404 Define one or more of 405 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() can not work e.g. 406 no 32KHz reference PIT/RTC clock 407 408- Clock Interface: 409 CONFIG_CLOCKS_IN_MHZ 410 411 U-Boot stores all clock information in Hz 412 internally. For binary compatibility with older Linux 413 kernels (which expect the clocks passed in the 414 bd_info data to be in MHz) the environment variable 415 "clocks_in_mhz" can be defined so that U-Boot 416 converts clock data to MHZ before passing it to the 417 Linux kernel. 418 419 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 420 "clocks_in_mhz=1" is automatically included in the 421 default environment. 422 423- Console Interface: 424 Depending on board, define exactly one serial port 425 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 426 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 427 console by defining CONFIG_8xx_CONS_NONE 428 429 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 430 port routines must be defined elsewhere 431 (i.e. serial_init(), serial_getc(), ...) 432 433 CONFIG_CFB_CONSOLE 434 Enables console device for a color framebuffer. Needs following 435 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 436 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 437 (default big endian) 438 VIDEO_HW_RECTFILL graphic chip supports 439 rectangle fill 440 (cf. smiLynxEM) 441 VIDEO_HW_BITBLT graphic chip supports 442 bit-blit (cf. smiLynxEM) 443 VIDEO_VISIBLE_COLS visible pixel columns 444 (cols=pitch) 445 VIDEO_VISIBLE_ROWS visible pixel rows 446 VIDEO_PIXEL_SIZE bytes per pixel 447 VIDEO_DATA_FORMAT graphic data format 448 (0-5, cf. cfb_console.c) 449 VIDEO_FB_ADRS framebuffer address 450 VIDEO_KBD_INIT_FCT keyboard int fct 451 (i.e. i8042_kbd_init()) 452 VIDEO_TSTC_FCT test char fct 453 (i.e. i8042_tstc) 454 VIDEO_GETC_FCT get char fct 455 (i.e. i8042_getc) 456 CONFIG_CONSOLE_CURSOR cursor drawing on/off 457 (requires blink timer 458 cf. i8042.c) 459 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 460 CONFIG_CONSOLE_TIME display time/date info in 461 upper right corner 462 (requires CFG_CMD_DATE) 463 CONFIG_VIDEO_LOGO display Linux logo in 464 upper left corner 465 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 466 linux_logo.h for logo. 467 Requires CONFIG_VIDEO_LOGO 468 CONFIG_CONSOLE_EXTRA_INFO 469 addional board info beside 470 the logo 471 472 When CONFIG_CFB_CONSOLE is defined, video console is 473 default i/o. Serial console can be forced with 474 environment 'console=serial'. 475 476- Console Baudrate: 477 CONFIG_BAUDRATE - in bps 478 Select one of the baudrates listed in 479 CFG_BAUDRATE_TABLE, see below. 480 481- Interrupt driven serial port input: 482 CONFIG_SERIAL_SOFTWARE_FIFO 483 484 PPC405GP only. 485 Use an interrupt handler for receiving data on the 486 serial port. It also enables using hardware handshake 487 (RTS/CTS) and UART's built-in FIFO. Set the number of 488 bytes the interrupt driven input buffer should have. 489 490 Set to 0 to disable this feature (this is the default). 491 This will also disable hardware handshake. 492 493- Console UART Number: 494 CONFIG_UART1_CONSOLE 495 496 IBM PPC4xx only. 497 If defined internal UART1 (and not UART0) is used 498 as default U-Boot console. 499 500- Boot Delay: CONFIG_BOOTDELAY - in seconds 501 Delay before automatically booting the default image; 502 set to -1 to disable autoboot. 503 504 See doc/README.autoboot for these options that 505 work with CONFIG_BOOTDELAY. None are required. 506 CONFIG_BOOT_RETRY_TIME 507 CONFIG_BOOT_RETRY_MIN 508 CONFIG_AUTOBOOT_KEYED 509 CONFIG_AUTOBOOT_PROMPT 510 CONFIG_AUTOBOOT_DELAY_STR 511 CONFIG_AUTOBOOT_STOP_STR 512 CONFIG_AUTOBOOT_DELAY_STR2 513 CONFIG_AUTOBOOT_STOP_STR2 514 CONFIG_ZERO_BOOTDELAY_CHECK 515 CONFIG_RESET_TO_RETRY 516 517- Autoboot Command: 518 CONFIG_BOOTCOMMAND 519 Only needed when CONFIG_BOOTDELAY is enabled; 520 define a command string that is automatically executed 521 when no character is read on the console interface 522 within "Boot Delay" after reset. 523 524 CONFIG_BOOTARGS 525 This can be used to pass arguments to the bootm 526 command. The value of CONFIG_BOOTARGS goes into the 527 environment value "bootargs". 528 529 CONFIG_RAMBOOT and CONFIG_NFSBOOT 530 The value of these goes into the environment as 531 "ramboot" and "nfsboot" respectively, and can be used 532 as a convenience, when switching between booting from 533 ram and nfs. 534 535- Pre-Boot Commands: 536 CONFIG_PREBOOT 537 538 When this option is #defined, the existence of the 539 environment variable "preboot" will be checked 540 immediately before starting the CONFIG_BOOTDELAY 541 countdown and/or running the auto-boot command resp. 542 entering interactive mode. 543 544 This feature is especially useful when "preboot" is 545 automatically generated or modified. For an example 546 see the LWMON board specific code: here "preboot" is 547 modified when the user holds down a certain 548 combination of keys on the (special) keyboard when 549 booting the systems 550 551- Serial Download Echo Mode: 552 CONFIG_LOADS_ECHO 553 If defined to 1, all characters received during a 554 serial download (using the "loads" command) are 555 echoed back. This might be needed by some terminal 556 emulations (like "cu"), but may as well just take 557 time on others. This setting #define's the initial 558 value of the "loads_echo" environment variable. 559 560- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined) 561 CONFIG_KGDB_BAUDRATE 562 Select one of the baudrates listed in 563 CFG_BAUDRATE_TABLE, see below. 564 565- Monitor Functions: 566 CONFIG_COMMANDS 567 Most monitor functions can be selected (or 568 de-selected) by adjusting the definition of 569 CONFIG_COMMANDS; to select individual functions, 570 #define CONFIG_COMMANDS by "OR"ing any of the 571 following values: 572 573 #define enables commands: 574 ------------------------- 575 CFG_CMD_ASKENV * ask for env variable 576 CFG_CMD_AUTOSCRIPT Autoscript Support 577 CFG_CMD_BDI bdinfo 578 CFG_CMD_BEDBUG Include BedBug Debugger 579 CFG_CMD_BMP * BMP support 580 CFG_CMD_BOOTD bootd 581 CFG_CMD_CACHE icache, dcache 582 CFG_CMD_CONSOLE coninfo 583 CFG_CMD_DATE * support for RTC, date/time... 584 CFG_CMD_DHCP DHCP support 585 CFG_CMD_DIAG * Diagnostics 586 CFG_CMD_DOC * Disk-On-Chip Support 587 CFG_CMD_DTT Digital Therm and Thermostat 588 CFG_CMD_ECHO * echo arguments 589 CFG_CMD_EEPROM * EEPROM read/write support 590 CFG_CMD_ELF bootelf, bootvx 591 CFG_CMD_ENV saveenv 592 CFG_CMD_FDC * Floppy Disk Support 593 CFG_CMD_FAT FAT partition support 594 CFG_CMD_FDOS * Dos diskette Support 595 CFG_CMD_FLASH flinfo, erase, protect 596 CFG_CMD_FPGA FPGA device initialization support 597 CFG_CMD_HWFLOW * RTS/CTS hw flow control 598 CFG_CMD_I2C * I2C serial bus support 599 CFG_CMD_IDE * IDE harddisk support 600 CFG_CMD_IMI iminfo 601 CFG_CMD_IMLS List all found images 602 CFG_CMD_IMMAP * IMMR dump support 603 CFG_CMD_IRQ * irqinfo 604 CFG_CMD_JFFS2 * JFFS2 Support 605 CFG_CMD_KGDB * kgdb 606 CFG_CMD_LOADB loadb 607 CFG_CMD_LOADS loads 608 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 609 loop, mtest 610 CFG_CMD_MISC Misc functions like sleep etc 611 CFG_CMD_MMC MMC memory mapped support 612 CFG_CMD_MII MII utility commands 613 CFG_CMD_NAND * NAND support 614 CFG_CMD_NET bootp, tftpboot, rarpboot 615 CFG_CMD_PCI * pciinfo 616 CFG_CMD_PCMCIA * PCMCIA support 617 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host 618 CFG_CMD_PORTIO Port I/O 619 CFG_CMD_REGINFO * Register dump 620 CFG_CMD_RUN run command in env variable 621 CFG_CMD_SAVES save S record dump 622 CFG_CMD_SCSI * SCSI Support 623 CFG_CMD_SDRAM * print SDRAM configuration information 624 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only) 625 CFG_CMD_SPI * SPI serial bus support 626 CFG_CMD_USB * USB support 627 CFG_CMD_VFD * VFD support (TRAB) 628 CFG_CMD_BSP * Board SPecific functions 629 ----------------------------------------------- 630 CFG_CMD_ALL all 631 632 CFG_CMD_DFL Default configuration; at the moment 633 this is includes all commands, except 634 the ones marked with "*" in the list 635 above. 636 637 If you don't define CONFIG_COMMANDS it defaults to 638 CFG_CMD_DFL in include/cmd_confdefs.h. A board can 639 override the default settings in the respective 640 include file. 641 642 EXAMPLE: If you want all functions except of network 643 support you can write: 644 645 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET) 646 647 648 Note: Don't enable the "icache" and "dcache" commands 649 (configuration option CFG_CMD_CACHE) unless you know 650 what you (and your U-Boot users) are doing. Data 651 cache cannot be enabled on systems like the 8xx or 652 8260 (where accesses to the IMMR region must be 653 uncached), and it cannot be disabled on all other 654 systems where we (mis-) use the data cache to hold an 655 initial stack and some data. 656 657 658 XXX - this list needs to get updated! 659 660- Watchdog: 661 CONFIG_WATCHDOG 662 If this variable is defined, it enables watchdog 663 support. There must be support in the platform specific 664 code for a watchdog. For the 8xx and 8260 CPUs, the 665 SIU Watchdog feature is enabled in the SYPCR 666 register. 667 668- U-Boot Version: 669 CONFIG_VERSION_VARIABLE 670 If this variable is defined, an environment variable 671 named "ver" is created by U-Boot showing the U-Boot 672 version as printed by the "version" command. 673 This variable is readonly. 674 675- Real-Time Clock: 676 677 When CFG_CMD_DATE is selected, the type of the RTC 678 has to be selected, too. Define exactly one of the 679 following options: 680 681 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 682 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 683 CONFIG_RTC_MC146818 - use MC146818 RTC 684 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 685 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 686 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 687 CONFIG_RTC_DS164x - use Dallas DS164x RTC 688 689 Note that if the RTC uses I2C, then the I2C interface 690 must also be configured. See I2C Support, below. 691 692- Timestamp Support: 693 694 When CONFIG_TIMESTAMP is selected, the timestamp 695 (date and time) of an image is printed by image 696 commands like bootm or iminfo. This option is 697 automatically enabled when you select CFG_CMD_DATE . 698 699- Partition Support: 700 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 701 and/or CONFIG_ISO_PARTITION 702 703 If IDE or SCSI support is enabled (CFG_CMD_IDE or 704 CFG_CMD_SCSI) you must configure support for at least 705 one partition type as well. 706 707- IDE Reset method: 708 CONFIG_IDE_RESET_ROUTINE 709 710 Set this to define that instead of a reset Pin, the 711 routine ide_set_reset(int idereset) will be used. 712 713- ATAPI Support: 714 CONFIG_ATAPI 715 716 Set this to enable ATAPI support. 717 718- SCSI Support: 719 At the moment only there is only support for the 720 SYM53C8XX SCSI controller; define 721 CONFIG_SCSI_SYM53C8XX to enable it. 722 723 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 724 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 725 CFG_SCSI_MAX_LUN] can be adjusted to define the 726 maximum numbers of LUNs, SCSI ID's and target 727 devices. 728 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 729 730- NETWORK Support (PCI): 731 CONFIG_E1000 732 Support for Intel 8254x gigabit chips. 733 734 CONFIG_EEPRO100 735 Support for Intel 82557/82559/82559ER chips. 736 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 737 write routine for first time initialisation. 738 739 CONFIG_TULIP 740 Support for Digital 2114x chips. 741 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 742 modem chip initialisation (KS8761/QS6611). 743 744 CONFIG_NATSEMI 745 Support for National dp83815 chips. 746 747 CONFIG_NS8382X 748 Support for National dp8382[01] gigabit chips. 749 750- NETWORK Support (other): 751 752 CONFIG_DRIVER_LAN91C96 753 Support for SMSC's LAN91C96 chips. 754 755 CONFIG_LAN91C96_BASE 756 Define this to hold the physical address 757 of the LAN91C96's I/O space 758 759 CONFIG_LAN91C96_USE_32_BIT 760 Define this to enable 32 bit addressing 761 762- USB Support: 763 At the moment only the UHCI host controller is 764 supported (PIP405, MIP405); define 765 CONFIG_USB_UHCI to enable it. 766 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 767 end define CONFIG_USB_STORAGE to enable the USB 768 storage devices. 769 Note: 770 Supported are USB Keyboards and USB Floppy drives 771 (TEAC FD-05PUB). 772 773- MMC Support: 774 The MMC controller on the Intel PXA is supported. To 775 enable this define CONFIG_MMC. The MMC can be 776 accessed from the boot prompt by mapping the device 777 to physical memory similar to flash. Command line is 778 enabled with CFG_CMD_MMC. The MMC driver also works with 779 the FAT fs. This is enabled with CFG_CMD_FAT. 780 781- Keyboard Support: 782 CONFIG_ISA_KEYBOARD 783 784 Define this to enable standard (PC-Style) keyboard 785 support 786 787 CONFIG_I8042_KBD 788 Standard PC keyboard driver with US (is default) and 789 GERMAN key layout (switch via environment 'keymap=de') support. 790 Export function i8042_kbd_init, i8042_tstc and i8042_getc 791 for cfb_console. Supports cursor blinking. 792 793- Video support: 794 CONFIG_VIDEO 795 796 Define this to enable video support (for output to 797 video). 798 799 CONFIG_VIDEO_CT69000 800 801 Enable Chips & Technologies 69000 Video chip 802 803 CONFIG_VIDEO_SMI_LYNXEM 804 Enable Silicon Motion SMI 712/710/810 Video chip 805 Videomode are selected via environment 'videomode' with 806 standard LiLo mode numbers. 807 Following modes are supported (* is default): 808 809 800x600 1024x768 1280x1024 810 256 (8bit) 303* 305 307 811 65536 (16bit) 314 317 31a 812 16,7 Mill (24bit) 315 318 31b 813 (i.e. setenv videomode 317; saveenv; reset;) 814 815 CONFIG_VIDEO_SED13806 816 Enable Epson SED13806 driver. This driver supports 8bpp 817 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 818 or CONFIG_VIDEO_SED13806_16BPP 819 820- Keyboard Support: 821 CONFIG_KEYBOARD 822 823 Define this to enable a custom keyboard support. 824 This simply calls drv_keyboard_init() which must be 825 defined in your board-specific files. 826 The only board using this so far is RBC823. 827 828- LCD Support: CONFIG_LCD 829 830 Define this to enable LCD support (for output to LCD 831 display); also select one of the supported displays 832 by defining one of these: 833 834 CONFIG_NEC_NL6648AC33: 835 836 NEC NL6648AC33-18. Active, color, single scan. 837 838 CONFIG_NEC_NL6648BC20 839 840 NEC NL6648BC20-08. 6.5", 640x480. 841 Active, color, single scan. 842 843 CONFIG_SHARP_16x9 844 845 Sharp 320x240. Active, color, single scan. 846 It isn't 16x9, and I am not sure what it is. 847 848 CONFIG_SHARP_LQ64D341 849 850 Sharp LQ64D341 display, 640x480. 851 Active, color, single scan. 852 853 CONFIG_HLD1045 854 855 HLD1045 display, 640x480. 856 Active, color, single scan. 857 858 CONFIG_OPTREX_BW 859 860 Optrex CBL50840-2 NF-FW 99 22 M5 861 or 862 Hitachi LMG6912RPFC-00T 863 or 864 Hitachi SP14Q002 865 866 320x240. Black & white. 867 868 Normally display is black on white background; define 869 CFG_WHITE_ON_BLACK to get it inverted. 870 871- Splash Screen Support: CONFIG_SPLASH_SCREEN 872 873 If this option is set, the environment is checked for 874 a variable "splashimage". If found, the usual display 875 of logo, copyright and system information on the LCD 876 is supressed and the BMP image at the address 877 specified in "splashimage" is loaded instead. The 878 console is redirected to the "nulldev", too. This 879 allows for a "silent" boot where a splash screen is 880 loaded very quickly after power-on. 881 882- Compression support: 883 CONFIG_BZIP2 884 885 If this option is set, support for bzip2 compressed 886 images is included. If not, only uncompressed and gzip 887 compressed images are supported. 888 889 NOTE: the bzip2 algorithm requires a lot of RAM, so 890 the malloc area (as defined by CFG_MALLOC_LEN) should 891 be at least 4MB. 892 893- Ethernet address: 894 CONFIG_ETHADDR 895 CONFIG_ETH2ADDR 896 CONFIG_ETH3ADDR 897 898 Define a default value for ethernet address to use 899 for the respective ethernet interface, in case this 900 is not determined automatically. 901 902- IP address: 903 CONFIG_IPADDR 904 905 Define a default value for the IP address to use for 906 the default ethernet interface, in case this is not 907 determined through e.g. bootp. 908 909- Server IP address: 910 CONFIG_SERVERIP 911 912 Defines a default value for theIP address of a TFTP 913 server to contact when using the "tftboot" command. 914 915- BOOTP Recovery Mode: 916 CONFIG_BOOTP_RANDOM_DELAY 917 918 If you have many targets in a network that try to 919 boot using BOOTP, you may want to avoid that all 920 systems send out BOOTP requests at precisely the same 921 moment (which would happen for instance at recovery 922 from a power failure, when all systems will try to 923 boot, thus flooding the BOOTP server. Defining 924 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 925 inserted before sending out BOOTP requests. The 926 following delays are insterted then: 927 928 1st BOOTP request: delay 0 ... 1 sec 929 2nd BOOTP request: delay 0 ... 2 sec 930 3rd BOOTP request: delay 0 ... 4 sec 931 4th and following 932 BOOTP requests: delay 0 ... 8 sec 933 934- DHCP Advanced Options: 935 CONFIG_BOOTP_MASK 936 937 You can fine tune the DHCP functionality by adding 938 these flags to the CONFIG_BOOTP_MASK define: 939 940 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 941 serverip from a DHCP server, it is possible that more 942 than one DNS serverip is offered to the client. 943 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 944 serverip will be stored in the additional environment 945 variable "dnsip2". The first DNS serverip is always 946 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 947 is added to the CONFIG_BOOTP_MASK. 948 949 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 950 to do a dynamic update of a DNS server. To do this, they 951 need the hostname of the DHCP requester. 952 If CONFIG_BOOP_SEND_HOSTNAME is added to the 953 CONFIG_BOOTP_MASK, the content of the "hostname" 954 environment variable is passed as option 12 to 955 the DHCP server. 956 957- Status LED: CONFIG_STATUS_LED 958 959 Several configurations allow to display the current 960 status using a LED. For instance, the LED will blink 961 fast while running U-Boot code, stop blinking as 962 soon as a reply to a BOOTP request was received, and 963 start blinking slow once the Linux kernel is running 964 (supported by a status LED driver in the Linux 965 kernel). Defining CONFIG_STATUS_LED enables this 966 feature in U-Boot. 967 968- CAN Support: CONFIG_CAN_DRIVER 969 970 Defining CONFIG_CAN_DRIVER enables CAN driver support 971 on those systems that support this (optional) 972 feature, like the TQM8xxL modules. 973 974- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 975 976 These enable I2C serial bus commands. Defining either of 977 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 978 include the appropriate I2C driver for the selected cpu. 979 980 This will allow you to use i2c commands at the u-boot 981 command line (as long as you set CFG_CMD_I2C in 982 CONFIG_COMMANDS) and communicate with i2c based realtime 983 clock chips. See common/cmd_i2c.c for a description of the 984 command line interface. 985 986 CONFIG_HARD_I2C selects the CPM hardware driver for I2C. 987 988 CONFIG_SOFT_I2C configures u-boot to use a software (aka 989 bit-banging) driver instead of CPM or similar hardware 990 support for I2C. 991 992 There are several other quantities that must also be 993 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 994 995 In both cases you will need to define CFG_I2C_SPEED 996 to be the frequency (in Hz) at which you wish your i2c bus 997 to run and CFG_I2C_SLAVE to be the address of this node (ie 998 the cpu's i2c node address). 999 1000 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1001 sets the cpu up as a master node and so its address should 1002 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1003 p.16-473). So, set CFG_I2C_SLAVE to 0. 1004 1005 That's all that's required for CONFIG_HARD_I2C. 1006 1007 If you use the software i2c interface (CONFIG_SOFT_I2C) 1008 then the following macros need to be defined (examples are 1009 from include/configs/lwmon.h): 1010 1011 I2C_INIT 1012 1013 (Optional). Any commands necessary to enable the I2C 1014 controller or configure ports. 1015 1016 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1017 1018 I2C_PORT 1019 1020 (Only for MPC8260 CPU). The I/O port to use (the code 1021 assumes both bits are on the same port). Valid values 1022 are 0..3 for ports A..D. 1023 1024 I2C_ACTIVE 1025 1026 The code necessary to make the I2C data line active 1027 (driven). If the data line is open collector, this 1028 define can be null. 1029 1030 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1031 1032 I2C_TRISTATE 1033 1034 The code necessary to make the I2C data line tri-stated 1035 (inactive). If the data line is open collector, this 1036 define can be null. 1037 1038 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1039 1040 I2C_READ 1041 1042 Code that returns TRUE if the I2C data line is high, 1043 FALSE if it is low. 1044 1045 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1046 1047 I2C_SDA(bit) 1048 1049 If <bit> is TRUE, sets the I2C data line high. If it 1050 is FALSE, it clears it (low). 1051 1052 eg: #define I2C_SDA(bit) \ 1053 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1054 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1055 1056 I2C_SCL(bit) 1057 1058 If <bit> is TRUE, sets the I2C clock line high. If it 1059 is FALSE, it clears it (low). 1060 1061 eg: #define I2C_SCL(bit) \ 1062 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1063 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1064 1065 I2C_DELAY 1066 1067 This delay is invoked four times per clock cycle so this 1068 controls the rate of data transfer. The data rate thus 1069 is 1 / (I2C_DELAY * 4). Often defined to be something 1070 like: 1071 1072 #define I2C_DELAY udelay(2) 1073 1074 CFG_I2C_INIT_BOARD 1075 1076 When a board is reset during an i2c bus transfer 1077 chips might think that the current transfer is still 1078 in progress. On some boards it is possible to access 1079 the i2c SCLK line directly, either by using the 1080 processor pin as a GPIO or by having a second pin 1081 connected to the bus. If this option is defined a 1082 custom i2c_init_board() routine in boards/xxx/board.c 1083 is run early in the boot sequence. 1084 1085- SPI Support: CONFIG_SPI 1086 1087 Enables SPI driver (so far only tested with 1088 SPI EEPROM, also an instance works with Crystal A/D and 1089 D/As on the SACSng board) 1090 1091 CONFIG_SPI_X 1092 1093 Enables extended (16-bit) SPI EEPROM addressing. 1094 (symmetrical to CONFIG_I2C_X) 1095 1096 CONFIG_SOFT_SPI 1097 1098 Enables a software (bit-bang) SPI driver rather than 1099 using hardware support. This is a general purpose 1100 driver that only requires three general I/O port pins 1101 (two outputs, one input) to function. If this is 1102 defined, the board configuration must define several 1103 SPI configuration items (port pins to use, etc). For 1104 an example, see include/configs/sacsng.h. 1105 1106- FPGA Support: CONFIG_FPGA_COUNT 1107 1108 Specify the number of FPGA devices to support. 1109 1110 CONFIG_FPGA 1111 1112 Used to specify the types of FPGA devices. For 1113 example, 1114 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 1115 1116 CFG_FPGA_PROG_FEEDBACK 1117 1118 Enable printing of hash marks during FPGA 1119 configuration. 1120 1121 CFG_FPGA_CHECK_BUSY 1122 1123 Enable checks on FPGA configuration interface busy 1124 status by the configuration function. This option 1125 will require a board or device specific function to 1126 be written. 1127 1128 CONFIG_FPGA_DELAY 1129 1130 If defined, a function that provides delays in the 1131 FPGA configuration driver. 1132 1133 CFG_FPGA_CHECK_CTRLC 1134 1135 Allow Control-C to interrupt FPGA configuration 1136 1137 CFG_FPGA_CHECK_ERROR 1138 1139 Check for configuration errors during FPGA bitfile 1140 loading. For example, abort during Virtex II 1141 configuration if the INIT_B line goes low (which 1142 indicated a CRC error). 1143 1144 CFG_FPGA_WAIT_INIT 1145 1146 Maximum time to wait for the INIT_B line to deassert 1147 after PROB_B has been deasserted during a Virtex II 1148 FPGA configuration sequence. The default time is 500 mS. 1149 1150 CFG_FPGA_WAIT_BUSY 1151 1152 Maximum time to wait for BUSY to deassert during 1153 Virtex II FPGA configuration. The default is 5 mS. 1154 1155 CFG_FPGA_WAIT_CONFIG 1156 1157 Time to wait after FPGA configuration. The default is 1158 200 mS. 1159 1160- FPGA Support: CONFIG_FPGA_COUNT 1161 1162 Specify the number of FPGA devices to support. 1163 1164 CONFIG_FPGA 1165 1166 Used to specify the types of FPGA devices. For example, 1167 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 1168 1169 CFG_FPGA_PROG_FEEDBACK 1170 1171 Enable printing of hash marks during FPGA configuration. 1172 1173 CFG_FPGA_CHECK_BUSY 1174 1175 Enable checks on FPGA configuration interface busy 1176 status by the configuration function. This option 1177 will require a board or device specific function to 1178 be written. 1179 1180 CONFIG_FPGA_DELAY 1181 1182 If defined, a function that provides delays in the FPGA 1183 configuration driver. 1184 1185 CFG_FPGA_CHECK_CTRLC 1186 Allow Control-C to interrupt FPGA configuration 1187 1188 CFG_FPGA_CHECK_ERROR 1189 1190 Check for configuration errors during FPGA bitfile 1191 loading. For example, abort during Virtex II 1192 configuration if the INIT_B line goes low (which 1193 indicated a CRC error). 1194 1195 CFG_FPGA_WAIT_INIT 1196 1197 Maximum time to wait for the INIT_B line to deassert 1198 after PROB_B has been deasserted during a Virtex II 1199 FPGA configuration sequence. The default time is 500 1200 mS. 1201 1202 CFG_FPGA_WAIT_BUSY 1203 1204 Maximum time to wait for BUSY to deassert during 1205 Virtex II FPGA configuration. The default is 5 mS. 1206 1207 CFG_FPGA_WAIT_CONFIG 1208 1209 Time to wait after FPGA configuration. The default is 1210 200 mS. 1211 1212- Configuration Management: 1213 CONFIG_IDENT_STRING 1214 1215 If defined, this string will be added to the U-Boot 1216 version information (U_BOOT_VERSION) 1217 1218- Vendor Parameter Protection: 1219 1220 U-Boot considers the values of the environment 1221 variables "serial#" (Board Serial Number) and 1222 "ethaddr" (Ethernet Address) to be parameters that 1223 are set once by the board vendor / manufacturer, and 1224 protects these variables from casual modification by 1225 the user. Once set, these variables are read-only, 1226 and write or delete attempts are rejected. You can 1227 change this behviour: 1228 1229 If CONFIG_ENV_OVERWRITE is #defined in your config 1230 file, the write protection for vendor parameters is 1231 completely disabled. Anybody can change or delete 1232 these parameters. 1233 1234 Alternatively, if you #define _both_ CONFIG_ETHADDR 1235 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1236 ethernet address is installed in the environment, 1237 which can be changed exactly ONCE by the user. [The 1238 serial# is unaffected by this, i. e. it remains 1239 read-only.] 1240 1241- Protected RAM: 1242 CONFIG_PRAM 1243 1244 Define this variable to enable the reservation of 1245 "protected RAM", i. e. RAM which is not overwritten 1246 by U-Boot. Define CONFIG_PRAM to hold the number of 1247 kB you want to reserve for pRAM. You can overwrite 1248 this default value by defining an environment 1249 variable "pram" to the number of kB you want to 1250 reserve. Note that the board info structure will 1251 still show the full amount of RAM. If pRAM is 1252 reserved, a new environment variable "mem" will 1253 automatically be defined to hold the amount of 1254 remaining RAM in a form that can be passed as boot 1255 argument to Linux, for instance like that: 1256 1257 setenv bootargs ... mem=\$(mem) 1258 saveenv 1259 1260 This way you can tell Linux not to use this memory, 1261 either, which results in a memory region that will 1262 not be affected by reboots. 1263 1264 *WARNING* If your board configuration uses automatic 1265 detection of the RAM size, you must make sure that 1266 this memory test is non-destructive. So far, the 1267 following board configurations are known to be 1268 "pRAM-clean": 1269 1270 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1271 HERMES, IP860, RPXlite, LWMON, LANTEC, 1272 PCU_E, FLAGADM, TQM8260 1273 1274- Error Recovery: 1275 CONFIG_PANIC_HANG 1276 1277 Define this variable to stop the system in case of a 1278 fatal error, so that you have to reset it manually. 1279 This is probably NOT a good idea for an embedded 1280 system where you want to system to reboot 1281 automatically as fast as possible, but it may be 1282 useful during development since you can try to debug 1283 the conditions that lead to the situation. 1284 1285 CONFIG_NET_RETRY_COUNT 1286 1287 This variable defines the number of retries for 1288 network operations like ARP, RARP, TFTP, or BOOTP 1289 before giving up the operation. If not defined, a 1290 default value of 5 is used. 1291 1292- Command Interpreter: 1293 CFG_HUSH_PARSER 1294 1295 Define this variable to enable the "hush" shell (from 1296 Busybox) as command line interpreter, thus enabling 1297 powerful command line syntax like 1298 if...then...else...fi conditionals or `&&' and '||' 1299 constructs ("shell scripts"). 1300 1301 If undefined, you get the old, much simpler behaviour 1302 with a somewhat smaller memory footprint. 1303 1304 1305 CFG_PROMPT_HUSH_PS2 1306 1307 This defines the secondary prompt string, which is 1308 printed when the command interpreter needs more input 1309 to complete a command. Usually "> ". 1310 1311 Note: 1312 1313 In the current implementation, the local variables 1314 space and global environment variables space are 1315 separated. Local variables are those you define by 1316 simply typing `name=value'. To access a local 1317 variable later on, you have write `$name' or 1318 `${name}'; to execute the contents of a variable 1319 directly type `$name' at the command prompt. 1320 1321 Global environment variables are those you use 1322 setenv/printenv to work with. To run a command stored 1323 in such a variable, you need to use the run command, 1324 and you must not use the '$' sign to access them. 1325 1326 To store commands and special characters in a 1327 variable, please use double quotation marks 1328 surrounding the whole text of the variable, instead 1329 of the backslashes before semicolons and special 1330 symbols. 1331 1332- Default Environment 1333 CONFIG_EXTRA_ENV_SETTINGS 1334 1335 Define this to contain any number of null terminated 1336 strings (variable = value pairs) that will be part of 1337 the default environment compiled into the boot image. 1338 1339 For example, place something like this in your 1340 board's config file: 1341 1342 #define CONFIG_EXTRA_ENV_SETTINGS \ 1343 "myvar1=value1\0" \ 1344 "myvar2=value2\0" 1345 1346 Warning: This method is based on knowledge about the 1347 internal format how the environment is stored by the 1348 U-Boot code. This is NOT an official, exported 1349 interface! Although it is unlikely that this format 1350 will change soon, there is no guarantee either. 1351 You better know what you are doing here. 1352 1353 Note: overly (ab)use of the default environment is 1354 discouraged. Make sure to check other ways to preset 1355 the environment like the autoscript function or the 1356 boot command first. 1357 1358- DataFlash Support 1359 CONFIG_HAS_DATAFLASH 1360 1361 Defining this option enables DataFlash features and 1362 allows to read/write in Dataflash via the standard 1363 commands cp, md... 1364 1365- Show boot progress 1366 CONFIG_SHOW_BOOT_PROGRESS 1367 1368 Defining this option allows to add some board- 1369 specific code (calling a user-provided function 1370 "show_boot_progress(int)") that enables you to show 1371 the system's boot progress on some display (for 1372 example, some LED's) on your board. At the moment, 1373 the following checkpoints are implemented: 1374 1375 Arg Where When 1376 1 common/cmd_bootm.c before attempting to boot an image 1377 -1 common/cmd_bootm.c Image header has bad magic number 1378 2 common/cmd_bootm.c Image header has correct magic number 1379 -2 common/cmd_bootm.c Image header has bad checksum 1380 3 common/cmd_bootm.c Image header has correct checksum 1381 -3 common/cmd_bootm.c Image data has bad checksum 1382 4 common/cmd_bootm.c Image data has correct checksum 1383 -4 common/cmd_bootm.c Image is for unsupported architecture 1384 5 common/cmd_bootm.c Architecture check OK 1385 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1386 6 common/cmd_bootm.c Image Type check OK 1387 -6 common/cmd_bootm.c gunzip uncompression error 1388 -7 common/cmd_bootm.c Unimplemented compression type 1389 7 common/cmd_bootm.c Uncompression OK 1390 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1391 8 common/cmd_bootm.c Image Type check OK 1392 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1393 9 common/cmd_bootm.c Start initial ramdisk verification 1394 -10 common/cmd_bootm.c Ramdisk header has bad magic number 1395 -11 common/cmd_bootm.c Ramdisk header has bad checksum 1396 10 common/cmd_bootm.c Ramdisk header is OK 1397 -12 common/cmd_bootm.c Ramdisk data has bad checksum 1398 11 common/cmd_bootm.c Ramdisk data has correct checksum 1399 12 common/cmd_bootm.c Ramdisk verification complete, start loading 1400 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk) 1401 13 common/cmd_bootm.c Start multifile image verification 1402 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue. 1403 15 common/cmd_bootm.c All preparation done, transferring control to OS 1404 1405 -1 common/cmd_doc.c Bad usage of "doc" command 1406 -1 common/cmd_doc.c No boot device 1407 -1 common/cmd_doc.c Unknown Chip ID on boot device 1408 -1 common/cmd_doc.c Read Error on boot device 1409 -1 common/cmd_doc.c Image header has bad magic number 1410 1411 -1 common/cmd_ide.c Bad usage of "ide" command 1412 -1 common/cmd_ide.c No boot device 1413 -1 common/cmd_ide.c Unknown boot device 1414 -1 common/cmd_ide.c Unknown partition table 1415 -1 common/cmd_ide.c Invalid partition type 1416 -1 common/cmd_ide.c Read Error on boot device 1417 -1 common/cmd_ide.c Image header has bad magic number 1418 1419 -1 common/cmd_nvedit.c Environment not changable, but has bad CRC 1420 1421 1422Modem Support: 1423-------------- 1424 1425[so far only for SMDK2400 and TRAB boards] 1426 1427- Modem support endable: 1428 CONFIG_MODEM_SUPPORT 1429 1430- RTS/CTS Flow control enable: 1431 CONFIG_HWFLOW 1432 1433- Modem debug support: 1434 CONFIG_MODEM_SUPPORT_DEBUG 1435 1436 Enables debugging stuff (char screen[1024], dbg()) 1437 for modem support. Useful only with BDI2000. 1438 1439- General: 1440 1441 In the target system modem support is enabled when a 1442 specific key (key combination) is pressed during 1443 power-on. Otherwise U-Boot will boot normally 1444 (autoboot). The key_pressed() fuction is called from 1445 board_init(). Currently key_pressed() is a dummy 1446 function, returning 1 and thus enabling modem 1447 initialization. 1448 1449 If there are no modem init strings in the 1450 environment, U-Boot proceed to autoboot; the 1451 previous output (banner, info printfs) will be 1452 supressed, though. 1453 1454 See also: doc/README.Modem 1455 1456 1457Configuration Settings: 1458----------------------- 1459 1460- CFG_LONGHELP: Defined when you want long help messages included; 1461 undefine this when you're short of memory. 1462 1463- CFG_PROMPT: This is what U-Boot prints on the console to 1464 prompt for user input. 1465 1466- CFG_CBSIZE: Buffer size for input from the Console 1467 1468- CFG_PBSIZE: Buffer size for Console output 1469 1470- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1471 1472- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1473 the application (usually a Linux kernel) when it is 1474 booted 1475 1476- CFG_BAUDRATE_TABLE: 1477 List of legal baudrate settings for this board. 1478 1479- CFG_CONSOLE_INFO_QUIET 1480 Suppress display of console information at boot. 1481 1482- CFG_CONSOLE_IS_IN_ENV 1483 If the board specific function 1484 extern int overwrite_console (void); 1485 returns 1, the stdin, stderr and stdout are switched to the 1486 serial port, else the settings in the environment are used. 1487 1488- CFG_CONSOLE_OVERWRITE_ROUTINE 1489 Enable the call to overwrite_console(). 1490 1491- CFG_CONSOLE_ENV_OVERWRITE 1492 Enable overwrite of previous console environment settings. 1493 1494- CFG_MEMTEST_START, CFG_MEMTEST_END: 1495 Begin and End addresses of the area used by the 1496 simple memory test. 1497 1498- CFG_ALT_MEMTEST: 1499 Enable an alternate, more extensive memory test. 1500 1501- CFG_MEMTEST_SCRATCH: 1502 Scratch address used by the alternate memory test 1503 You only need to set this if address zero isn't writeable 1504 1505- CFG_TFTP_LOADADDR: 1506 Default load address for network file downloads 1507 1508- CFG_LOADS_BAUD_CHANGE: 1509 Enable temporary baudrate change while serial download 1510 1511- CFG_SDRAM_BASE: 1512 Physical start address of SDRAM. _Must_ be 0 here. 1513 1514- CFG_MBIO_BASE: 1515 Physical start address of Motherboard I/O (if using a 1516 Cogent motherboard) 1517 1518- CFG_FLASH_BASE: 1519 Physical start address of Flash memory. 1520 1521- CFG_MONITOR_BASE: 1522 Physical start address of boot monitor code (set by 1523 make config files to be same as the text base address 1524 (TEXT_BASE) used when linking) - same as 1525 CFG_FLASH_BASE when booting from flash. 1526 1527- CFG_MONITOR_LEN: 1528 Size of memory reserved for monitor code, used to 1529 determine _at_compile_time_ (!) if the environment is 1530 embedded within the U-Boot image, or in a separate 1531 flash sector. 1532 1533- CFG_MALLOC_LEN: 1534 Size of DRAM reserved for malloc() use. 1535 1536- CFG_BOOTMAPSZ: 1537 Maximum size of memory mapped by the startup code of 1538 the Linux kernel; all data that must be processed by 1539 the Linux kernel (bd_info, boot arguments, eventually 1540 initrd image) must be put below this limit. 1541 1542- CFG_MAX_FLASH_BANKS: 1543 Max number of Flash memory banks 1544 1545- CFG_MAX_FLASH_SECT: 1546 Max number of sectors on a Flash chip 1547 1548- CFG_FLASH_ERASE_TOUT: 1549 Timeout for Flash erase operations (in ms) 1550 1551- CFG_FLASH_WRITE_TOUT: 1552 Timeout for Flash write operations (in ms) 1553 1554- CFG_FLASH_LOCK_TOUT 1555 Timeout for Flash set sector lock bit operation (in ms) 1556 1557- CFG_FLASH_UNLOCK_TOUT 1558 Timeout for Flash clear lock bits operation (in ms) 1559 1560- CFG_FLASH_PROTECTION 1561 If defined, hardware flash sectors protection is used 1562 instead of U-Boot software protection. 1563 1564- CFG_DIRECT_FLASH_TFTP: 1565 1566 Enable TFTP transfers directly to flash memory; 1567 without this option such a download has to be 1568 performed in two steps: (1) download to RAM, and (2) 1569 copy from RAM to flash. 1570 1571 The two-step approach is usually more reliable, since 1572 you can check if the download worked before you erase 1573 the flash, but in some situations (when sytem RAM is 1574 too limited to allow for a tempory copy of the 1575 downloaded image) this option may be very useful. 1576 1577- CFG_FLASH_CFI: 1578 Define if the flash driver uses extra elements in the 1579 common flash structure for storing flash geometry 1580 1581- CFG_RX_ETH_BUFFER: 1582 Defines the number of ethernet receive buffers. On some 1583 ethernet controllers it is recommended to set this value 1584 to 8 or even higher (EEPRO100 or 405 EMAC), since all 1585 buffers can be full shortly after enabling the interface 1586 on high ethernet traffic. 1587 Defaults to 4 if not defined. 1588 1589The following definitions that deal with the placement and management 1590of environment data (variable area); in general, we support the 1591following configurations: 1592 1593- CFG_ENV_IS_IN_FLASH: 1594 1595 Define this if the environment is in flash memory. 1596 1597 a) The environment occupies one whole flash sector, which is 1598 "embedded" in the text segment with the U-Boot code. This 1599 happens usually with "bottom boot sector" or "top boot 1600 sector" type flash chips, which have several smaller 1601 sectors at the start or the end. For instance, such a 1602 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 1603 such a case you would place the environment in one of the 1604 4 kB sectors - with U-Boot code before and after it. With 1605 "top boot sector" type flash chips, you would put the 1606 environment in one of the last sectors, leaving a gap 1607 between U-Boot and the environment. 1608 1609 - CFG_ENV_OFFSET: 1610 1611 Offset of environment data (variable area) to the 1612 beginning of flash memory; for instance, with bottom boot 1613 type flash chips the second sector can be used: the offset 1614 for this sector is given here. 1615 1616 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 1617 1618 - CFG_ENV_ADDR: 1619 1620 This is just another way to specify the start address of 1621 the flash sector containing the environment (instead of 1622 CFG_ENV_OFFSET). 1623 1624 - CFG_ENV_SECT_SIZE: 1625 1626 Size of the sector containing the environment. 1627 1628 1629 b) Sometimes flash chips have few, equal sized, BIG sectors. 1630 In such a case you don't want to spend a whole sector for 1631 the environment. 1632 1633 - CFG_ENV_SIZE: 1634 1635 If you use this in combination with CFG_ENV_IS_IN_FLASH 1636 and CFG_ENV_SECT_SIZE, you can specify to use only a part 1637 of this flash sector for the environment. This saves 1638 memory for the RAM copy of the environment. 1639 1640 It may also save flash memory if you decide to use this 1641 when your environment is "embedded" within U-Boot code, 1642 since then the remainder of the flash sector could be used 1643 for U-Boot code. It should be pointed out that this is 1644 STRONGLY DISCOURAGED from a robustness point of view: 1645 updating the environment in flash makes it always 1646 necessary to erase the WHOLE sector. If something goes 1647 wrong before the contents has been restored from a copy in 1648 RAM, your target system will be dead. 1649 1650 - CFG_ENV_ADDR_REDUND 1651 CFG_ENV_SIZE_REDUND 1652 1653 These settings describe a second storage area used to hold 1654 a redundand copy of the environment data, so that there is 1655 a valid backup copy in case there is a power failure during 1656 a "saveenv" operation. 1657 1658BE CAREFUL! Any changes to the flash layout, and some changes to the 1659source code will make it necessary to adapt <board>/u-boot.lds* 1660accordingly! 1661 1662 1663- CFG_ENV_IS_IN_NVRAM: 1664 1665 Define this if you have some non-volatile memory device 1666 (NVRAM, battery buffered SRAM) which you want to use for the 1667 environment. 1668 1669 - CFG_ENV_ADDR: 1670 - CFG_ENV_SIZE: 1671 1672 These two #defines are used to determin the memory area you 1673 want to use for environment. It is assumed that this memory 1674 can just be read and written to, without any special 1675 provision. 1676 1677BE CAREFUL! The first access to the environment happens quite early 1678in U-Boot initalization (when we try to get the setting of for the 1679console baudrate). You *MUST* have mappend your NVRAM area then, or 1680U-Boot will hang. 1681 1682Please note that even with NVRAM we still use a copy of the 1683environment in RAM: we could work on NVRAM directly, but we want to 1684keep settings there always unmodified except somebody uses "saveenv" 1685to save the current settings. 1686 1687 1688- CFG_ENV_IS_IN_EEPROM: 1689 1690 Use this if you have an EEPROM or similar serial access 1691 device and a driver for it. 1692 1693 - CFG_ENV_OFFSET: 1694 - CFG_ENV_SIZE: 1695 1696 These two #defines specify the offset and size of the 1697 environment area within the total memory of your EEPROM. 1698 1699 - CFG_I2C_EEPROM_ADDR: 1700 If defined, specified the chip address of the EEPROM device. 1701 The default address is zero. 1702 1703 - CFG_EEPROM_PAGE_WRITE_BITS: 1704 If defined, the number of bits used to address bytes in a 1705 single page in the EEPROM device. A 64 byte page, for example 1706 would require six bits. 1707 1708 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 1709 If defined, the number of milliseconds to delay between 1710 page writes. The default is zero milliseconds. 1711 1712 - CFG_I2C_EEPROM_ADDR_LEN: 1713 The length in bytes of the EEPROM memory array address. Note 1714 that this is NOT the chip address length! 1715 1716 - CFG_EEPROM_SIZE: 1717 The size in bytes of the EEPROM device. 1718 1719 1720- CFG_SPI_INIT_OFFSET 1721 1722 Defines offset to the initial SPI buffer area in DPRAM. The 1723 area is used at an early stage (ROM part) if the environment 1724 is configured to reside in the SPI EEPROM: We need a 520 byte 1725 scratch DPRAM area. It is used between the two initialization 1726 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 1727 to be a good choice since it makes it far enough from the 1728 start of the data area as well as from the stack pointer. 1729 1730Please note that the environment is read-only as long as the monitor 1731has been relocated to RAM and a RAM copy of the environment has been 1732created; also, when using EEPROM you will have to use getenv_r() 1733until then to read environment variables. 1734 1735The environment is protected by a CRC32 checksum. Before the monitor 1736is relocated into RAM, as a result of a bad CRC you will be working 1737with the compiled-in default environment - *silently*!!! [This is 1738necessary, because the first environment variable we need is the 1739"baudrate" setting for the console - if we have a bad CRC, we don't 1740have any device yet where we could complain.] 1741 1742Note: once the monitor has been relocated, then it will complain if 1743the default environment is used; a new CRC is computed as soon as you 1744use the "saveenv" command to store a valid environment. 1745 1746 1747Low Level (hardware related) configuration options: 1748--------------------------------------------------- 1749 1750- CFG_CACHELINE_SIZE: 1751 Cache Line Size of the CPU. 1752 1753- CFG_DEFAULT_IMMR: 1754 Default address of the IMMR after system reset. 1755 1756 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 1757 and RPXsuper) to be able to adjust the position of 1758 the IMMR register after a reset. 1759 1760- Floppy Disk Support: 1761 CFG_FDC_DRIVE_NUMBER 1762 1763 the default drive number (default value 0) 1764 1765 CFG_ISA_IO_STRIDE 1766 1767 defines the spacing between fdc chipset registers 1768 (default value 1) 1769 1770 CFG_ISA_IO_OFFSET 1771 1772 defines the offset of register from address. It 1773 depends on which part of the data bus is connected to 1774 the fdc chipset. (default value 0) 1775 1776 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 1777 CFG_FDC_DRIVE_NUMBER are undefined, they take their 1778 default value. 1779 1780 if CFG_FDC_HW_INIT is defined, then the function 1781 fdc_hw_init() is called at the beginning of the FDC 1782 setup. fdc_hw_init() must be provided by the board 1783 source code. It is used to make hardware dependant 1784 initializations. 1785 1786- CFG_IMMR: Physical address of the Internal Memory Mapped 1787 Register; DO NOT CHANGE! (11-4) 1788 [MPC8xx systems only] 1789 1790- CFG_INIT_RAM_ADDR: 1791 1792 Start address of memory area that can be used for 1793 initial data and stack; please note that this must be 1794 writable memory that is working WITHOUT special 1795 initialization, i. e. you CANNOT use normal RAM which 1796 will become available only after programming the 1797 memory controller and running certain initialization 1798 sequences. 1799 1800 U-Boot uses the following memory types: 1801 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 1802 - MPC824X: data cache 1803 - PPC4xx: data cache 1804 1805- CFG_GBL_DATA_OFFSET: 1806 1807 Offset of the initial data structure in the memory 1808 area defined by CFG_INIT_RAM_ADDR. Usually 1809 CFG_GBL_DATA_OFFSET is chosen such that the initial 1810 data is located at the end of the available space 1811 (sometimes written as (CFG_INIT_RAM_END - 1812 CFG_INIT_DATA_SIZE), and the initial stack is just 1813 below that area (growing from (CFG_INIT_RAM_ADDR + 1814 CFG_GBL_DATA_OFFSET) downward. 1815 1816 Note: 1817 On the MPC824X (or other systems that use the data 1818 cache for initial memory) the address chosen for 1819 CFG_INIT_RAM_ADDR is basically arbitrary - it must 1820 point to an otherwise UNUSED address space between 1821 the top of RAM and the start of the PCI space. 1822 1823- CFG_SIUMCR: SIU Module Configuration (11-6) 1824 1825- CFG_SYPCR: System Protection Control (11-9) 1826 1827- CFG_TBSCR: Time Base Status and Control (11-26) 1828 1829- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 1830 1831- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 1832 1833- CFG_SCCR: System Clock and reset Control Register (15-27) 1834 1835- CFG_OR_TIMING_SDRAM: 1836 SDRAM timing 1837 1838- CFG_MAMR_PTA: 1839 periodic timer for refresh 1840 1841- CFG_DER: Debug Event Register (37-47) 1842 1843- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 1844 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 1845 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 1846 CFG_BR1_PRELIM: 1847 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 1848 1849- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 1850 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 1851 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 1852 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 1853 1854- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 1855 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 1856 Machine Mode Register and Memory Periodic Timer 1857 Prescaler definitions (SDRAM timing) 1858 1859- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 1860 enable I2C microcode relocation patch (MPC8xx); 1861 define relocation offset in DPRAM [DSP2] 1862 1863- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 1864 enable SPI microcode relocation patch (MPC8xx); 1865 define relocation offset in DPRAM [SCC4] 1866 1867- CFG_USE_OSCCLK: 1868 Use OSCM clock mode on MBX8xx board. Be careful, 1869 wrong setting might damage your board. Read 1870 doc/README.MBX before setting this variable! 1871 1872- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 1873 Offset of the bootmode word in DPRAM used by post 1874 (Power On Self Tests). This definition overrides 1875 #define'd default value in commproc.h resp. 1876 cpm_8260.h. 1877 1878- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 1879 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 1880 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 1881 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 1882 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 1883 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 1884 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 1885 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 1886 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 1887 1888Building the Software: 1889====================== 1890 1891Building U-Boot has been tested in native PPC environments (on a 1892PowerBook G3 running LinuxPPC 2000) and in cross environments 1893(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and 1894NetBSD 1.5 on x86). 1895 1896If you are not using a native PPC environment, it is assumed that you 1897have the GNU cross compiling tools available in your path and named 1898with a prefix of "powerpc-linux-". If this is not the case, (e.g. if 1899you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change 1900the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU, 1901change it to: 1902 1903 CROSS_COMPILE = ppc_4xx- 1904 1905 1906U-Boot is intended to be simple to build. After installing the 1907sources you must configure U-Boot for one specific board type. This 1908is done by typing: 1909 1910 make NAME_config 1911 1912where "NAME_config" is the name of one of the existing 1913configurations; the following names are supported: 1914 1915 ADCIOP_config GTH_config TQM850L_config 1916 ADS860_config IP860_config TQM855L_config 1917 AR405_config IVML24_config TQM860L_config 1918 CANBT_config IVMS8_config WALNUT405_config 1919 CPCI405_config LANTEC_config cogent_common_config 1920 CPCIISER4_config MBX_config cogent_mpc8260_config 1921 CU824_config MBX860T_config cogent_mpc8xx_config 1922 ESTEEM192E_config RPXlite_config hermes_config 1923 ETX094_config RPXsuper_config hymod_config 1924 FADS823_config SM850_config lwmon_config 1925 FADS850SAR_config SPD823TS_config pcu_e_config 1926 FADS860T_config SXNI855T_config rsdproto_config 1927 FPS850L_config Sandpoint8240_config sbc8260_config 1928 GENIETV_config TQM823L_config PIP405_config 1929 GEN860T_config EBONY_config FPS860L_config 1930 ELPT860_config cmi_mpc5xx_config NETVIA_config 1931 at91rm9200dk_config omap1510inn_config MPC8260ADS_config 1932 omap1610inn_config 1933Note: for some board special configuration names may exist; check if 1934 additional information is available from the board vendor; for 1935 instance, the TQM8xxL systems run normally at 50 MHz and use a 1936 SCC for 10baseT ethernet; there are also systems with 80 MHz 1937 CPU clock, and an optional Fast Ethernet module is available 1938 for CPU's with FEC. You can select such additional "features" 1939 when chosing the configuration, i. e. 1940 1941 make TQM860L_config 1942 - will configure for a plain TQM860L, i. e. 50MHz, no FEC 1943 1944 make TQM860L_FEC_config 1945 - will configure for a TQM860L at 50MHz with FEC for ethernet 1946 1947 make TQM860L_80MHz_config 1948 - will configure for a TQM860L at 80 MHz, with normal 10baseT 1949 interface 1950 1951 make TQM860L_FEC_80MHz_config 1952 - will configure for a TQM860L at 80 MHz with FEC for ethernet 1953 1954 make TQM823L_LCD_config 1955 - will configure for a TQM823L with U-Boot console on LCD 1956 1957 make TQM823L_LCD_80MHz_config 1958 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD 1959 1960 etc. 1961 1962 1963Finally, type "make all", and you should get some working U-Boot 1964images ready for download to / installation on your system: 1965 1966- "u-boot.bin" is a raw binary image 1967- "u-boot" is an image in ELF binary format 1968- "u-boot.srec" is in Motorola S-Record format 1969 1970 1971Please be aware that the Makefiles assume you are using GNU make, so 1972for instance on NetBSD you might need to use "gmake" instead of 1973native "make". 1974 1975 1976If the system board that you have is not listed, then you will need 1977to port U-Boot to your hardware platform. To do this, follow these 1978steps: 1979 19801. Add a new configuration option for your board to the toplevel 1981 "Makefile" and to the "MAKEALL" script, using the existing 1982 entries as examples. Note that here and at many other places 1983 boards and other names are listed in alphabetical sort order. Please 1984 keep this order. 19852. Create a new directory to hold your board specific code. Add any 1986 files you need. In your board directory, you will need at least 1987 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 19883. Create a new configuration file "include/configs/<board>.h" for 1989 your board 19903. If you're porting U-Boot to a new CPU, then also create a new 1991 directory to hold your CPU specific code. Add any files you need. 19924. Run "make <board>_config" with your new name. 19935. Type "make", and you should get a working "u-boot.srec" file 1994 to be installed on your target system. 19956. Debug and solve any problems that might arise. 1996 [Of course, this last step is much harder than it sounds.] 1997 1998 1999Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2000============================================================== 2001 2002If you have modified U-Boot sources (for instance added a new board 2003or support for new devices, a new CPU, etc.) you are expected to 2004provide feedback to the other developers. The feedback normally takes 2005the form of a "patch", i. e. a context diff against a certain (latest 2006official or latest in CVS) version of U-Boot sources. 2007 2008But before you submit such a patch, please verify that your modifi- 2009cation did not break existing code. At least make sure that *ALL* of 2010the supported boards compile WITHOUT ANY compiler warnings. To do so, 2011just run the "MAKEALL" script, which will configure and build U-Boot 2012for ALL supported system. Be warned, this will take a while. You can 2013select which (cross) compiler to use by passing a `CROSS_COMPILE' 2014environment variable to the script, i. e. to use the cross tools from 2015MontaVista's Hard Hat Linux you can type 2016 2017 CROSS_COMPILE=ppc_8xx- MAKEALL 2018 2019or to build on a native PowerPC system you can type 2020 2021 CROSS_COMPILE=' ' MAKEALL 2022 2023See also "U-Boot Porting Guide" below. 2024 2025 2026Monitor Commands - Overview: 2027============================ 2028 2029go - start application at address 'addr' 2030run - run commands in an environment variable 2031bootm - boot application image from memory 2032bootp - boot image via network using BootP/TFTP protocol 2033tftpboot- boot image via network using TFTP protocol 2034 and env variables "ipaddr" and "serverip" 2035 (and eventually "gatewayip") 2036rarpboot- boot image via network using RARP/TFTP protocol 2037diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2038loads - load S-Record file over serial line 2039loadb - load binary file over serial line (kermit mode) 2040md - memory display 2041mm - memory modify (auto-incrementing) 2042nm - memory modify (constant address) 2043mw - memory write (fill) 2044cp - memory copy 2045cmp - memory compare 2046crc32 - checksum calculation 2047imd - i2c memory display 2048imm - i2c memory modify (auto-incrementing) 2049inm - i2c memory modify (constant address) 2050imw - i2c memory write (fill) 2051icrc32 - i2c checksum calculation 2052iprobe - probe to discover valid I2C chip addresses 2053iloop - infinite loop on address range 2054isdram - print SDRAM configuration information 2055sspi - SPI utility commands 2056base - print or set address offset 2057printenv- print environment variables 2058setenv - set environment variables 2059saveenv - save environment variables to persistent storage 2060protect - enable or disable FLASH write protection 2061erase - erase FLASH memory 2062flinfo - print FLASH memory information 2063bdinfo - print Board Info structure 2064iminfo - print header information for application image 2065coninfo - print console devices and informations 2066ide - IDE sub-system 2067loop - infinite loop on address range 2068mtest - simple RAM test 2069icache - enable or disable instruction cache 2070dcache - enable or disable data cache 2071reset - Perform RESET of the CPU 2072echo - echo args to console 2073version - print monitor version 2074help - print online help 2075? - alias for 'help' 2076 2077 2078Monitor Commands - Detailed Description: 2079======================================== 2080 2081TODO. 2082 2083For now: just type "help <command>". 2084 2085 2086Environment Variables: 2087====================== 2088 2089U-Boot supports user configuration using Environment Variables which 2090can be made persistent by saving to Flash memory. 2091 2092Environment Variables are set using "setenv", printed using 2093"printenv", and saved to Flash using "saveenv". Using "setenv" 2094without a value can be used to delete a variable from the 2095environment. As long as you don't save the environment you are 2096working with an in-memory copy. In case the Flash area containing the 2097environment is erased by accident, a default environment is provided. 2098 2099Some configuration options can be set using Environment Variables: 2100 2101 baudrate - see CONFIG_BAUDRATE 2102 2103 bootdelay - see CONFIG_BOOTDELAY 2104 2105 bootcmd - see CONFIG_BOOTCOMMAND 2106 2107 bootargs - Boot arguments when booting an RTOS image 2108 2109 bootfile - Name of the image to load with TFTP 2110 2111 autoload - if set to "no" (any string beginning with 'n'), 2112 "bootp" will just load perform a lookup of the 2113 configuration from the BOOTP server, but not try to 2114 load any image using TFTP 2115 2116 autostart - if set to "yes", an image loaded using the "bootp", 2117 "rarpboot", "tftpboot" or "diskboot" commands will 2118 be automatically started (by internally calling 2119 "bootm") 2120 2121 If set to "no", a standalone image passed to the 2122 "bootm" command will be copied to the load address 2123 (and eventually uncompressed), but NOT be started. 2124 This can be used to load and uncompress arbitrary 2125 data. 2126 2127 initrd_high - restrict positioning of initrd images: 2128 If this variable is not set, initrd images will be 2129 copied to the highest possible address in RAM; this 2130 is usually what you want since it allows for 2131 maximum initrd size. If for some reason you want to 2132 make sure that the initrd image is loaded below the 2133 CFG_BOOTMAPSZ limit, you can set this environment 2134 variable to a value of "no" or "off" or "0". 2135 Alternatively, you can set it to a maximum upper 2136 address to use (U-Boot will still check that it 2137 does not overwrite the U-Boot stack and data). 2138 2139 For instance, when you have a system with 16 MB 2140 RAM, and want to reserve 4 MB from use by Linux, 2141 you can do this by adding "mem=12M" to the value of 2142 the "bootargs" variable. However, now you must make 2143 sure that the initrd image is placed in the first 2144 12 MB as well - this can be done with 2145 2146 setenv initrd_high 00c00000 2147 2148 If you set initrd_high to 0xFFFFFFFF, this is an 2149 indication to U-Boot that all addresses are legal 2150 for the Linux kernel, including addresses in flash 2151 memory. In this case U-Boot will NOT COPY the 2152 ramdisk at all. This may be useful to reduce the 2153 boot time on your system, but requires that this 2154 feature is supported by your Linux kernel. 2155 2156 ipaddr - IP address; needed for tftpboot command 2157 2158 loadaddr - Default load address for commands like "bootp", 2159 "rarpboot", "tftpboot", "loadb" or "diskboot" 2160 2161 loads_echo - see CONFIG_LOADS_ECHO 2162 2163 serverip - TFTP server IP address; needed for tftpboot command 2164 2165 bootretry - see CONFIG_BOOT_RETRY_TIME 2166 2167 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2168 2169 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2170 2171 2172The following environment variables may be used and automatically 2173updated by the network boot commands ("bootp" and "rarpboot"), 2174depending the information provided by your boot server: 2175 2176 bootfile - see above 2177 dnsip - IP address of your Domain Name Server 2178 dnsip2 - IP address of your secondary Domain Name Server 2179 gatewayip - IP address of the Gateway (Router) to use 2180 hostname - Target hostname 2181 ipaddr - see above 2182 netmask - Subnet Mask 2183 rootpath - Pathname of the root filesystem on the NFS server 2184 serverip - see above 2185 2186 2187There are two special Environment Variables: 2188 2189 serial# - contains hardware identification information such 2190 as type string and/or serial number 2191 ethaddr - Ethernet address 2192 2193These variables can be set only once (usually during manufacturing of 2194the board). U-Boot refuses to delete or overwrite these variables 2195once they have been set once. 2196 2197 2198Further special Environment Variables: 2199 2200 ver - Contains the U-Boot version string as printed 2201 with the "version" command. This variable is 2202 readonly (see CONFIG_VERSION_VARIABLE). 2203 2204 2205Please note that changes to some configuration parameters may take 2206only effect after the next boot (yes, that's just like Windoze :-). 2207 2208 2209Command Line Parsing: 2210===================== 2211 2212There are two different command line parsers available with U-Boot: 2213the old "simple" one, and the much more powerful "hush" shell: 2214 2215Old, simple command line parser: 2216-------------------------------- 2217 2218- supports environment variables (through setenv / saveenv commands) 2219- several commands on one line, separated by ';' 2220- variable substitution using "... $(name) ..." syntax 2221- special characters ('$', ';') can be escaped by prefixing with '\', 2222 for example: 2223 setenv bootcmd bootm \$(address) 2224- You can also escape text by enclosing in single apostrophes, for example: 2225 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2226 2227Hush shell: 2228----------- 2229 2230- similar to Bourne shell, with control structures like 2231 if...then...else...fi, for...do...done; while...do...done, 2232 until...do...done, ... 2233- supports environment ("global") variables (through setenv / saveenv 2234 commands) and local shell variables (through standard shell syntax 2235 "name=value"); only environment variables can be used with "run" 2236 command 2237 2238General rules: 2239-------------- 2240 2241(1) If a command line (or an environment variable executed by a "run" 2242 command) contains several commands separated by semicolon, and 2243 one of these commands fails, then the remaining commands will be 2244 executed anyway. 2245 2246(2) If you execute several variables with one call to run (i. e. 2247 calling run with a list af variables as arguments), any failing 2248 command will cause "run" to terminate, i. e. the remaining 2249 variables are not executed. 2250 2251Note for Redundant Ethernet Interfaces: 2252======================================= 2253 2254Some boards come with redundant ethernet interfaces; U-Boot supports 2255such configurations and is capable of automatic selection of a 2256"working" interface when needed. MAC assignment works as follows: 2257 2258Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2259MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2260"eth1addr" (=>eth1), "eth2addr", ... 2261 2262If the network interface stores some valid MAC address (for instance 2263in SROM), this is used as default address if there is NO correspon- 2264ding setting in the environment; if the corresponding environment 2265variable is set, this overrides the settings in the card; that means: 2266 2267o If the SROM has a valid MAC address, and there is no address in the 2268 environment, the SROM's address is used. 2269 2270o If there is no valid address in the SROM, and a definition in the 2271 environment exists, then the value from the environment variable is 2272 used. 2273 2274o If both the SROM and the environment contain a MAC address, and 2275 both addresses are the same, this MAC address is used. 2276 2277o If both the SROM and the environment contain a MAC address, and the 2278 addresses differ, the value from the environment is used and a 2279 warning is printed. 2280 2281o If neither SROM nor the environment contain a MAC address, an error 2282 is raised. 2283 2284 2285Image Formats: 2286============== 2287 2288The "boot" commands of this monitor operate on "image" files which 2289can be basicly anything, preceeded by a special header; see the 2290definitions in include/image.h for details; basicly, the header 2291defines the following image properties: 2292 2293* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2294 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2295 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2296 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 2297* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86, 2298 IA64, MIPS, MIPS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 2299 Currently supported: PowerPC). 2300* Compression Type (uncompressed, gzip, bzip2) 2301* Load Address 2302* Entry Point 2303* Image Name 2304* Image Timestamp 2305 2306The header is marked by a special Magic Number, and both the header 2307and the data portions of the image are secured against corruption by 2308CRC32 checksums. 2309 2310 2311Linux Support: 2312============== 2313 2314Although U-Boot should support any OS or standalone application 2315easily, the main focus has always been on Linux during the design of 2316U-Boot. 2317 2318U-Boot includes many features that so far have been part of some 2319special "boot loader" code within the Linux kernel. Also, any 2320"initrd" images to be used are no longer part of one big Linux image; 2321instead, kernel and "initrd" are separate images. This implementation 2322serves several purposes: 2323 2324- the same features can be used for other OS or standalone 2325 applications (for instance: using compressed images to reduce the 2326 Flash memory footprint) 2327 2328- it becomes much easier to port new Linux kernel versions because 2329 lots of low-level, hardware dependent stuff are done by U-Boot 2330 2331- the same Linux kernel image can now be used with different "initrd" 2332 images; of course this also means that different kernel images can 2333 be run with the same "initrd". This makes testing easier (you don't 2334 have to build a new "zImage.initrd" Linux image when you just 2335 change a file in your "initrd"). Also, a field-upgrade of the 2336 software is easier now. 2337 2338 2339Linux HOWTO: 2340============ 2341 2342Porting Linux to U-Boot based systems: 2343--------------------------------------- 2344 2345U-Boot cannot save you from doing all the necessary modifications to 2346configure the Linux device drivers for use with your target hardware 2347(no, we don't intend to provide a full virtual machine interface to 2348Linux :-). 2349 2350But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 2351 2352Just make sure your machine specific header file (for instance 2353include/asm-ppc/tqm8xx.h) includes the same definition of the Board 2354Information structure as we define in include/u-boot.h, and make 2355sure that your definition of IMAP_ADDR uses the same value as your 2356U-Boot configuration in CFG_IMMR. 2357 2358 2359Configuring the Linux kernel: 2360----------------------------- 2361 2362No specific requirements for U-Boot. Make sure you have some root 2363device (initial ramdisk, NFS) for your target system. 2364 2365 2366Building a Linux Image: 2367----------------------- 2368 2369With U-Boot, "normal" build targets like "zImage" or "bzImage" are 2370not used. If you use recent kernel source, a new build target 2371"uImage" will exist which automatically builds an image usable by 2372U-Boot. Most older kernels also have support for a "pImage" target, 2373which was introduced for our predecessor project PPCBoot and uses a 2374100% compatible format. 2375 2376Example: 2377 2378 make TQM850L_config 2379 make oldconfig 2380 make dep 2381 make uImage 2382 2383The "uImage" build target uses a special tool (in 'tools/mkimage') to 2384encapsulate a compressed Linux kernel image with header information, 2385CRC32 checksum etc. for use with U-Boot. This is what we are doing: 2386 2387* build a standard "vmlinux" kernel image (in ELF binary format): 2388 2389* convert the kernel into a raw binary image: 2390 2391 ${CROSS_COMPILE}-objcopy -O binary \ 2392 -R .note -R .comment \ 2393 -S vmlinux linux.bin 2394 2395* compress the binary image: 2396 2397 gzip -9 linux.bin 2398 2399* package compressed binary image for U-Boot: 2400 2401 mkimage -A ppc -O linux -T kernel -C gzip \ 2402 -a 0 -e 0 -n "Linux Kernel Image" \ 2403 -d linux.bin.gz uImage 2404 2405 2406The "mkimage" tool can also be used to create ramdisk images for use 2407with U-Boot, either separated from the Linux kernel image, or 2408combined into one file. "mkimage" encapsulates the images with a 64 2409byte header containing information about target architecture, 2410operating system, image type, compression method, entry points, time 2411stamp, CRC32 checksums, etc. 2412 2413"mkimage" can be called in two ways: to verify existing images and 2414print the header information, or to build new images. 2415 2416In the first form (with "-l" option) mkimage lists the information 2417contained in the header of an existing U-Boot image; this includes 2418checksum verification: 2419 2420 tools/mkimage -l image 2421 -l ==> list image header information 2422 2423The second form (with "-d" option) is used to build a U-Boot image 2424from a "data file" which is used as image payload: 2425 2426 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 2427 -n name -d data_file image 2428 -A ==> set architecture to 'arch' 2429 -O ==> set operating system to 'os' 2430 -T ==> set image type to 'type' 2431 -C ==> set compression type 'comp' 2432 -a ==> set load address to 'addr' (hex) 2433 -e ==> set entry point to 'ep' (hex) 2434 -n ==> set image name to 'name' 2435 -d ==> use image data from 'datafile' 2436 2437Right now, all Linux kernels use the same load address (0x00000000), 2438but the entry point address depends on the kernel version: 2439 2440- 2.2.x kernels have the entry point at 0x0000000C, 2441- 2.3.x and later kernels have the entry point at 0x00000000. 2442 2443So a typical call to build a U-Boot image would read: 2444 2445 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2446 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 2447 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 2448 > examples/uImage.TQM850L 2449 Image Name: 2.4.4 kernel for TQM850L 2450 Created: Wed Jul 19 02:34:59 2000 2451 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2452 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2453 Load Address: 0x00000000 2454 Entry Point: 0x00000000 2455 2456To verify the contents of the image (or check for corruption): 2457 2458 -> tools/mkimage -l examples/uImage.TQM850L 2459 Image Name: 2.4.4 kernel for TQM850L 2460 Created: Wed Jul 19 02:34:59 2000 2461 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2462 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2463 Load Address: 0x00000000 2464 Entry Point: 0x00000000 2465 2466NOTE: for embedded systems where boot time is critical you can trade 2467speed for memory and install an UNCOMPRESSED image instead: this 2468needs more space in Flash, but boots much faster since it does not 2469need to be uncompressed: 2470 2471 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 2472 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2473 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 2474 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 2475 > examples/uImage.TQM850L-uncompressed 2476 Image Name: 2.4.4 kernel for TQM850L 2477 Created: Wed Jul 19 02:34:59 2000 2478 Image Type: PowerPC Linux Kernel Image (uncompressed) 2479 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 2480 Load Address: 0x00000000 2481 Entry Point: 0x00000000 2482 2483 2484Similar you can build U-Boot images from a 'ramdisk.image.gz' file 2485when your kernel is intended to use an initial ramdisk: 2486 2487 -> tools/mkimage -n 'Simple Ramdisk Image' \ 2488 > -A ppc -O linux -T ramdisk -C gzip \ 2489 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 2490 Image Name: Simple Ramdisk Image 2491 Created: Wed Jan 12 14:01:50 2000 2492 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2493 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 2494 Load Address: 0x00000000 2495 Entry Point: 0x00000000 2496 2497 2498Installing a Linux Image: 2499------------------------- 2500 2501To downloading a U-Boot image over the serial (console) interface, 2502you must convert the image to S-Record format: 2503 2504 objcopy -I binary -O srec examples/image examples/image.srec 2505 2506The 'objcopy' does not understand the information in the U-Boot 2507image header, so the resulting S-Record file will be relative to 2508address 0x00000000. To load it to a given address, you need to 2509specify the target address as 'offset' parameter with the 'loads' 2510command. 2511 2512Example: install the image to address 0x40100000 (which on the 2513TQM8xxL is in the first Flash bank): 2514 2515 => erase 40100000 401FFFFF 2516 2517 .......... done 2518 Erased 8 sectors 2519 2520 => loads 40100000 2521 ## Ready for S-Record download ... 2522 ~>examples/image.srec 2523 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 2524 ... 2525 15989 15990 15991 15992 2526 [file transfer complete] 2527 [connected] 2528 ## Start Addr = 0x00000000 2529 2530 2531You can check the success of the download using the 'iminfo' command; 2532this includes a checksum verification so you can be sure no data 2533corruption happened: 2534 2535 => imi 40100000 2536 2537 ## Checking Image at 40100000 ... 2538 Image Name: 2.2.13 for initrd on TQM850L 2539 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2540 Data Size: 335725 Bytes = 327 kB = 0 MB 2541 Load Address: 00000000 2542 Entry Point: 0000000c 2543 Verifying Checksum ... OK 2544 2545 2546Boot Linux: 2547----------- 2548 2549The "bootm" command is used to boot an application that is stored in 2550memory (RAM or Flash). In case of a Linux kernel image, the contents 2551of the "bootargs" environment variable is passed to the kernel as 2552parameters. You can check and modify this variable using the 2553"printenv" and "setenv" commands: 2554 2555 2556 => printenv bootargs 2557 bootargs=root=/dev/ram 2558 2559 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2560 2561 => printenv bootargs 2562 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2563 2564 => bootm 40020000 2565 ## Booting Linux kernel at 40020000 ... 2566 Image Name: 2.2.13 for NFS on TQM850L 2567 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2568 Data Size: 381681 Bytes = 372 kB = 0 MB 2569 Load Address: 00000000 2570 Entry Point: 0000000c 2571 Verifying Checksum ... OK 2572 Uncompressing Kernel Image ... OK 2573 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 2574 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2575 time_init: decrementer frequency = 187500000/60 2576 Calibrating delay loop... 49.77 BogoMIPS 2577 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 2578 ... 2579 2580If you want to boot a Linux kernel with initial ram disk, you pass 2581the memory addresses of both the kernel and the initrd image (PPBCOOT 2582format!) to the "bootm" command: 2583 2584 => imi 40100000 40200000 2585 2586 ## Checking Image at 40100000 ... 2587 Image Name: 2.2.13 for initrd on TQM850L 2588 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2589 Data Size: 335725 Bytes = 327 kB = 0 MB 2590 Load Address: 00000000 2591 Entry Point: 0000000c 2592 Verifying Checksum ... OK 2593 2594 ## Checking Image at 40200000 ... 2595 Image Name: Simple Ramdisk Image 2596 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2597 Data Size: 566530 Bytes = 553 kB = 0 MB 2598 Load Address: 00000000 2599 Entry Point: 00000000 2600 Verifying Checksum ... OK 2601 2602 => bootm 40100000 40200000 2603 ## Booting Linux kernel at 40100000 ... 2604 Image Name: 2.2.13 for initrd on TQM850L 2605 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2606 Data Size: 335725 Bytes = 327 kB = 0 MB 2607 Load Address: 00000000 2608 Entry Point: 0000000c 2609 Verifying Checksum ... OK 2610 Uncompressing Kernel Image ... OK 2611 ## Loading RAMDisk Image at 40200000 ... 2612 Image Name: Simple Ramdisk Image 2613 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2614 Data Size: 566530 Bytes = 553 kB = 0 MB 2615 Load Address: 00000000 2616 Entry Point: 00000000 2617 Verifying Checksum ... OK 2618 Loading Ramdisk ... OK 2619 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 2620 Boot arguments: root=/dev/ram 2621 time_init: decrementer frequency = 187500000/60 2622 Calibrating delay loop... 49.77 BogoMIPS 2623 ... 2624 RAMDISK: Compressed image found at block 0 2625 VFS: Mounted root (ext2 filesystem). 2626 2627 bash# 2628 2629More About U-Boot Image Types: 2630------------------------------ 2631 2632U-Boot supports the following image types: 2633 2634 "Standalone Programs" are directly runnable in the environment 2635 provided by U-Boot; it is expected that (if they behave 2636 well) you can continue to work in U-Boot after return from 2637 the Standalone Program. 2638 "OS Kernel Images" are usually images of some Embedded OS which 2639 will take over control completely. Usually these programs 2640 will install their own set of exception handlers, device 2641 drivers, set up the MMU, etc. - this means, that you cannot 2642 expect to re-enter U-Boot except by resetting the CPU. 2643 "RAMDisk Images" are more or less just data blocks, and their 2644 parameters (address, size) are passed to an OS kernel that is 2645 being started. 2646 "Multi-File Images" contain several images, typically an OS 2647 (Linux) kernel image and one or more data images like 2648 RAMDisks. This construct is useful for instance when you want 2649 to boot over the network using BOOTP etc., where the boot 2650 server provides just a single image file, but you want to get 2651 for instance an OS kernel and a RAMDisk image. 2652 2653 "Multi-File Images" start with a list of image sizes, each 2654 image size (in bytes) specified by an "uint32_t" in network 2655 byte order. This list is terminated by an "(uint32_t)0". 2656 Immediately after the terminating 0 follow the images, one by 2657 one, all aligned on "uint32_t" boundaries (size rounded up to 2658 a multiple of 4 bytes). 2659 2660 "Firmware Images" are binary images containing firmware (like 2661 U-Boot or FPGA images) which usually will be programmed to 2662 flash memory. 2663 2664 "Script files" are command sequences that will be executed by 2665 U-Boot's command interpreter; this feature is especially 2666 useful when you configure U-Boot to use a real shell (hush) 2667 as command interpreter. 2668 2669 2670Standalone HOWTO: 2671================= 2672 2673One of the features of U-Boot is that you can dynamically load and 2674run "standalone" applications, which can use some resources of 2675U-Boot like console I/O functions or interrupt services. 2676 2677Two simple examples are included with the sources: 2678 2679"Hello World" Demo: 2680------------------- 2681 2682'examples/hello_world.c' contains a small "Hello World" Demo 2683application; it is automatically compiled when you build U-Boot. 2684It's configured to run at address 0x00040004, so you can play with it 2685like that: 2686 2687 => loads 2688 ## Ready for S-Record download ... 2689 ~>examples/hello_world.srec 2690 1 2 3 4 5 6 7 8 9 10 11 ... 2691 [file transfer complete] 2692 [connected] 2693 ## Start Addr = 0x00040004 2694 2695 => go 40004 Hello World! This is a test. 2696 ## Starting application at 0x00040004 ... 2697 Hello World 2698 argc = 7 2699 argv[0] = "40004" 2700 argv[1] = "Hello" 2701 argv[2] = "World!" 2702 argv[3] = "This" 2703 argv[4] = "is" 2704 argv[5] = "a" 2705 argv[6] = "test." 2706 argv[7] = "<NULL>" 2707 Hit any key to exit ... 2708 2709 ## Application terminated, rc = 0x0 2710 2711Another example, which demonstrates how to register a CPM interrupt 2712handler with the U-Boot code, can be found in 'examples/timer.c'. 2713Here, a CPM timer is set up to generate an interrupt every second. 2714The interrupt service routine is trivial, just printing a '.' 2715character, but this is just a demo program. The application can be 2716controlled by the following keys: 2717 2718 ? - print current values og the CPM Timer registers 2719 b - enable interrupts and start timer 2720 e - stop timer and disable interrupts 2721 q - quit application 2722 2723 => loads 2724 ## Ready for S-Record download ... 2725 ~>examples/timer.srec 2726 1 2 3 4 5 6 7 8 9 10 11 ... 2727 [file transfer complete] 2728 [connected] 2729 ## Start Addr = 0x00040004 2730 2731 => go 40004 2732 ## Starting application at 0x00040004 ... 2733 TIMERS=0xfff00980 2734 Using timer 1 2735 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 2736 2737Hit 'b': 2738 [q, b, e, ?] Set interval 1000000 us 2739 Enabling timer 2740Hit '?': 2741 [q, b, e, ?] ........ 2742 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 2743Hit '?': 2744 [q, b, e, ?] . 2745 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 2746Hit '?': 2747 [q, b, e, ?] . 2748 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 2749Hit '?': 2750 [q, b, e, ?] . 2751 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 2752Hit 'e': 2753 [q, b, e, ?] ...Stopping timer 2754Hit 'q': 2755 [q, b, e, ?] ## Application terminated, rc = 0x0 2756 2757 2758Minicom warning: 2759================ 2760 2761Over time, many people have reported problems when trying to use the 2762"minicom" terminal emulation program for serial download. I (wd) 2763consider minicom to be broken, and recommend not to use it. Under 2764Unix, I recommend to use C-Kermit for general purpose use (and 2765especially for kermit binary protocol download ("loadb" command), and 2766use "cu" for S-Record download ("loads" command). 2767 2768Nevertheless, if you absolutely want to use it try adding this 2769configuration to your "File transfer protocols" section: 2770 2771 Name Program Name U/D FullScr IO-Red. Multi 2772 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 2773 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 2774 2775 2776NetBSD Notes: 2777============= 2778 2779Starting at version 0.9.2, U-Boot supports NetBSD both as host 2780(build U-Boot) and target system (boots NetBSD/mpc8xx). 2781 2782Building requires a cross environment; it is known to work on 2783NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 2784need gmake since the Makefiles are not compatible with BSD make). 2785Note that the cross-powerpc package does not install include files; 2786attempting to build U-Boot will fail because <machine/ansi.h> is 2787missing. This file has to be installed and patched manually: 2788 2789 # cd /usr/pkg/cross/powerpc-netbsd/include 2790 # mkdir powerpc 2791 # ln -s powerpc machine 2792 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 2793 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 2794 2795Native builds *don't* work due to incompatibilities between native 2796and U-Boot include files. 2797 2798Booting assumes that (the first part of) the image booted is a 2799stage-2 loader which in turn loads and then invokes the kernel 2800proper. Loader sources will eventually appear in the NetBSD source 2801tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 2802meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for 2803details. 2804 2805 2806Implementation Internals: 2807========================= 2808 2809The following is not intended to be a complete description of every 2810implementation detail. However, it should help to understand the 2811inner workings of U-Boot and make it easier to port it to custom 2812hardware. 2813 2814 2815Initial Stack, Global Data: 2816--------------------------- 2817 2818The implementation of U-Boot is complicated by the fact that U-Boot 2819starts running out of ROM (flash memory), usually without access to 2820system RAM (because the memory controller is not initialized yet). 2821This means that we don't have writable Data or BSS segments, and BSS 2822is not initialized as zero. To be able to get a C environment working 2823at all, we have to allocate at least a minimal stack. Implementation 2824options for this are defined and restricted by the CPU used: Some CPU 2825models provide on-chip memory (like the IMMR area on MPC8xx and 2826MPC826x processors), on others (parts of) the data cache can be 2827locked as (mis-) used as memory, etc. 2828 2829 Chris Hallinan posted a good summary of these issues to the 2830 u-boot-users mailing list: 2831 2832 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 2833 From: "Chris Hallinan" <clh@net1plus.com> 2834 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 2835 ... 2836 2837 Correct me if I'm wrong, folks, but the way I understand it 2838 is this: Using DCACHE as initial RAM for Stack, etc, does not 2839 require any physical RAM backing up the cache. The cleverness 2840 is that the cache is being used as a temporary supply of 2841 necessary storage before the SDRAM controller is setup. It's 2842 beyond the scope of this list to expain the details, but you 2843 can see how this works by studying the cache architecture and 2844 operation in the architecture and processor-specific manuals. 2845 2846 OCM is On Chip Memory, which I believe the 405GP has 4K. It 2847 is another option for the system designer to use as an 2848 initial stack/ram area prior to SDRAM being available. Either 2849 option should work for you. Using CS 4 should be fine if your 2850 board designers haven't used it for something that would 2851 cause you grief during the initial boot! It is frequently not 2852 used. 2853 2854 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 2855 with your processor/board/system design. The default value 2856 you will find in any recent u-boot distribution in 2857 Walnut405.h should work for you. I'd set it to a value larger 2858 than your SDRAM module. If you have a 64MB SDRAM module, set 2859 it above 400_0000. Just make sure your board has no resources 2860 that are supposed to respond to that address! That code in 2861 start.S has been around a while and should work as is when 2862 you get the config right. 2863 2864 -Chris Hallinan 2865 DS4.COM, Inc. 2866 2867It is essential to remember this, since it has some impact on the C 2868code for the initialization procedures: 2869 2870* Initialized global data (data segment) is read-only. Do not attempt 2871 to write it. 2872 2873* Do not use any unitialized global data (or implicitely initialized 2874 as zero data - BSS segment) at all - this is undefined, initiali- 2875 zation is performed later (when relocating to RAM). 2876 2877* Stack space is very limited. Avoid big data buffers or things like 2878 that. 2879 2880Having only the stack as writable memory limits means we cannot use 2881normal global data to share information beween the code. But it 2882turned out that the implementation of U-Boot can be greatly 2883simplified by making a global data structure (gd_t) available to all 2884functions. We could pass a pointer to this data as argument to _all_ 2885functions, but this would bloat the code. Instead we use a feature of 2886the GCC compiler (Global Register Variables) to share the data: we 2887place a pointer (gd) to the global data into a register which we 2888reserve for this purpose. 2889 2890When choosing a register for such a purpose we are restricted by the 2891relevant (E)ABI specifications for the current architecture, and by 2892GCC's implementation. 2893 2894For PowerPC, the following registers have specific use: 2895 R1: stack pointer 2896 R2: TOC pointer 2897 R3-R4: parameter passing and return values 2898 R5-R10: parameter passing 2899 R13: small data area pointer 2900 R30: GOT pointer 2901 R31: frame pointer 2902 2903 (U-Boot also uses R14 as internal GOT pointer.) 2904 2905 ==> U-Boot will use R29 to hold a pointer to the global data 2906 2907 Note: on PPC, we could use a static initializer (since the 2908 address of the global data structure is known at compile time), 2909 but it turned out that reserving a register results in somewhat 2910 smaller code - although the code savings are not that big (on 2911 average for all boards 752 bytes for the whole U-Boot image, 2912 624 text + 127 data). 2913 2914On ARM, the following registers are used: 2915 2916 R0: function argument word/integer result 2917 R1-R3: function argument word 2918 R9: GOT pointer 2919 R10: stack limit (used only if stack checking if enabled) 2920 R11: argument (frame) pointer 2921 R12: temporary workspace 2922 R13: stack pointer 2923 R14: link register 2924 R15: program counter 2925 2926 ==> U-Boot will use R8 to hold a pointer to the global data 2927 2928 2929Memory Management: 2930------------------ 2931 2932U-Boot runs in system state and uses physical addresses, i.e. the 2933MMU is not used either for address mapping nor for memory protection. 2934 2935The available memory is mapped to fixed addresses using the memory 2936controller. In this process, a contiguous block is formed for each 2937memory type (Flash, SDRAM, SRAM), even when it consists of several 2938physical memory banks. 2939 2940U-Boot is installed in the first 128 kB of the first Flash bank (on 2941TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 2942booting and sizing and initializing DRAM, the code relocates itself 2943to the upper end of DRAM. Immediately below the U-Boot code some 2944memory is reserved for use by malloc() [see CFG_MALLOC_LEN 2945configuration setting]. Below that, a structure with global Board 2946Info data is placed, followed by the stack (growing downward). 2947 2948Additionally, some exception handler code is copied to the low 8 kB 2949of DRAM (0x00000000 ... 0x00001FFF). 2950 2951So a typical memory configuration with 16 MB of DRAM could look like 2952this: 2953 2954 0x0000 0000 Exception Vector code 2955 : 2956 0x0000 1FFF 2957 0x0000 2000 Free for Application Use 2958 : 2959 : 2960 2961 : 2962 : 2963 0x00FB FF20 Monitor Stack (Growing downward) 2964 0x00FB FFAC Board Info Data and permanent copy of global data 2965 0x00FC 0000 Malloc Arena 2966 : 2967 0x00FD FFFF 2968 0x00FE 0000 RAM Copy of Monitor Code 2969 ... eventually: LCD or video framebuffer 2970 ... eventually: pRAM (Protected RAM - unchanged by reset) 2971 0x00FF FFFF [End of RAM] 2972 2973 2974System Initialization: 2975---------------------- 2976 2977In the reset configuration, U-Boot starts at the reset entry point 2978(on most PowerPC systens at address 0x00000100). Because of the reset 2979configuration for CS0# this is a mirror of the onboard Flash memory. 2980To be able to re-map memory U-Boot then jumps to its link address. 2981To be able to implement the initialization code in C, a (small!) 2982initial stack is set up in the internal Dual Ported RAM (in case CPUs 2983which provide such a feature like MPC8xx or MPC8260), or in a locked 2984part of the data cache. After that, U-Boot initializes the CPU core, 2985the caches and the SIU. 2986 2987Next, all (potentially) available memory banks are mapped using a 2988preliminary mapping. For example, we put them on 512 MB boundaries 2989(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 2990on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 2991programmed for SDRAM access. Using the temporary configuration, a 2992simple memory test is run that determines the size of the SDRAM 2993banks. 2994 2995When there is more than one SDRAM bank, and the banks are of 2996different size, the largest is mapped first. For equal size, the first 2997bank (CS2#) is mapped first. The first mapping is always for address 29980x00000000, with any additional banks following immediately to create 2999contiguous memory starting from 0. 3000 3001Then, the monitor installs itself at the upper end of the SDRAM area 3002and allocates memory for use by malloc() and for the global Board 3003Info data; also, the exception vector code is copied to the low RAM 3004pages, and the final stack is set up. 3005 3006Only after this relocation will you have a "normal" C environment; 3007until that you are restricted in several ways, mostly because you are 3008running from ROM, and because the code will have to be relocated to a 3009new address in RAM. 3010 3011 3012U-Boot Porting Guide: 3013---------------------- 3014 3015[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3016list, October 2002] 3017 3018 3019int main (int argc, char *argv[]) 3020{ 3021 sighandler_t no_more_time; 3022 3023 signal (SIGALRM, no_more_time); 3024 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3025 3026 if (available_money > available_manpower) { 3027 pay consultant to port U-Boot; 3028 return 0; 3029 } 3030 3031 Download latest U-Boot source; 3032 3033 Subscribe to u-boot-users mailing list; 3034 3035 if (clueless) { 3036 email ("Hi, I am new to U-Boot, how do I get started?"); 3037 } 3038 3039 while (learning) { 3040 Read the README file in the top level directory; 3041 Read http://www.denx.de/re/DPLG.html 3042 Read the source, Luke; 3043 } 3044 3045 if (available_money > toLocalCurrency ($2500)) { 3046 Buy a BDI2000; 3047 } else { 3048 Add a lot of aggravation and time; 3049 } 3050 3051 Create your own board support subdirectory; 3052 3053 Create your own board config file; 3054 3055 while (!running) { 3056 do { 3057 Add / modify source code; 3058 } until (compiles); 3059 Debug; 3060 if (clueless) 3061 email ("Hi, I am having problems..."); 3062 } 3063 Send patch file to Wolfgang; 3064 3065 return 0; 3066} 3067 3068void no_more_time (int sig) 3069{ 3070 hire_a_guru(); 3071} 3072 3073 3074Coding Standards: 3075----------------- 3076 3077All contributions to U-Boot should conform to the Linux kernel 3078coding style; see the file "Documentation/CodingStyle" in your Linux 3079kernel source directory. 3080 3081Please note that U-Boot is implemented in C (and to some small parts 3082in Assembler); no C++ is used, so please do not use C++ style 3083comments (//) in your code. 3084 3085Submissions which do not conform to the standards may be returned 3086with a request to reformat the changes. 3087 3088 3089Submitting Patches: 3090------------------- 3091 3092Since the number of patches for U-Boot is growing, we need to 3093establish some rules. Submissions which do not conform to these rules 3094may be rejected, even when they contain important and valuable stuff. 3095 3096 3097When you send a patch, please include the following information with 3098it: 3099 3100* For bug fixes: a description of the bug and how your patch fixes 3101 this bug. Please try to include a way of demonstrating that the 3102 patch actually fixes something. 3103 3104* For new features: a description of the feature and your 3105 implementation. 3106 3107* A CHANGELOG entry as plaintext (separate from the patch) 3108 3109* For major contributions, your entry to the CREDITS file 3110 3111* When you add support for a new board, don't forget to add this 3112 board to the MAKEALL script, too. 3113 3114* If your patch adds new configuration options, don't forget to 3115 document these in the README file. 3116 3117* The patch itself. If you are accessing the CVS repository use "cvs 3118 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your 3119 version of diff does not support these options, then get the latest 3120 version of GNU diff. 3121 3122 The current directory when running this command shall be the top 3123 level directory of the U-Boot source tree, or it's parent directory 3124 (i. e. please make sure that your patch includes sufficient 3125 directory information for the affected files). 3126 3127 We accept patches as plain text, MIME attachments or as uuencoded 3128 gzipped text. 3129 3130* If one logical set of modifications affects or creates several 3131 files, all these changes shall be submitted in a SINGLE patch file. 3132 3133* Changesets that contain different, unrelated modifications shall be 3134 submitted as SEPARATE patches, one patch per changeset. 3135 3136 3137Notes: 3138 3139* Before sending the patch, run the MAKEALL script on your patched 3140 source tree and make sure that no errors or warnings are reported 3141 for any of the boards. 3142 3143* Keep your modifications to the necessary minimum: A patch 3144 containing several unrelated changes or arbitrary reformats will be 3145 returned with a request to re-formatting / split it. 3146 3147* If you modify existing code, make sure that your new code does not 3148 add to the memory footprint of the code ;-) Small is beautiful! 3149 When adding new features, these should compile conditionally only 3150 (using #ifdef), and the resulting code with the new feature 3151 disabled must not need more memory than the old code without your 3152 modification. 3153