1# 2# (C) Copyright 2000 - 2005 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, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. 55 56 57Where to get help: 58================== 59 60In case you have questions about, problems with or contributions for 61U-Boot you should send a message to the U-Boot mailing list at 62<u-boot-users@lists.sourceforge.net>. There is also an archive of 63previous traffic on the mailing list - please search the archive 64before asking FAQ's. Please see 65http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 66 67 68Where we come from: 69=================== 70 71- start from 8xxrom sources 72- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 73- clean up code 74- make it easier to add custom boards 75- make it possible to add other [PowerPC] CPUs 76- extend functions, especially: 77 * Provide extended interface to Linux boot loader 78 * S-Record download 79 * network boot 80 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot 81- create ARMBoot project (http://sourceforge.net/projects/armboot) 82- add other CPU families (starting with ARM) 83- create U-Boot project (http://sourceforge.net/projects/u-boot) 84 85 86Names and Spelling: 87=================== 88 89The "official" name of this project is "Das U-Boot". The spelling 90"U-Boot" shall be used in all written text (documentation, comments 91in source files etc.). Example: 92 93 This is the README file for the U-Boot project. 94 95File names etc. shall be based on the string "u-boot". Examples: 96 97 include/asm-ppc/u-boot.h 98 99 #include <asm/u-boot.h> 100 101Variable names, preprocessor constants etc. shall be either based on 102the string "u_boot" or on "U_BOOT". Example: 103 104 U_BOOT_VERSION u_boot_logo 105 IH_OS_U_BOOT u_boot_hush_start 106 107 108Versioning: 109=========== 110 111U-Boot uses a 3 level version number containing a version, a 112sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 113sub-version "34", and patchlevel "4". 114 115The patchlevel is used to indicate certain stages of development 116between released versions, i. e. officially released versions of 117U-Boot will always have a patchlevel of "0". 118 119 120Directory Hierarchy: 121==================== 122 123- board Board dependent files 124- common Misc architecture independent functions 125- cpu CPU specific files 126 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 127 - arm720t Files specific to ARM 720 CPUs 128 - arm920t Files specific to ARM 920 CPUs 129 - at91rm9200 Files specific to Atmel AT91RM9200 CPU 130 - imx Files specific to Freescale MC9328 i.MX CPUs 131 - s3c24x0 Files specific to Samsung S3C24X0 CPUs 132 - arm925t Files specific to ARM 925 CPUs 133 - arm926ejs Files specific to ARM 926 CPUs 134 - arm1136 Files specific to ARM 1136 CPUs 135 - at32ap Files specific to Atmel AVR32 AP CPUs 136 - i386 Files specific to i386 CPUs 137 - ixp Files specific to Intel XScale IXP CPUs 138 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 139 - mips Files specific to MIPS CPUs 140 - mpc5xx Files specific to Freescale MPC5xx CPUs 141 - mpc5xxx Files specific to Freescale MPC5xxx CPUs 142 - mpc8xx Files specific to Freescale MPC8xx CPUs 143 - mpc8220 Files specific to Freescale MPC8220 CPUs 144 - mpc824x Files specific to Freescale MPC824x CPUs 145 - mpc8260 Files specific to Freescale MPC8260 CPUs 146 - mpc85xx Files specific to Freescale MPC85xx CPUs 147 - nios Files specific to Altera NIOS CPUs 148 - nios2 Files specific to Altera Nios-II CPUs 149 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs 150 - pxa Files specific to Intel XScale PXA CPUs 151 - s3c44b0 Files specific to Samsung S3C44B0 CPUs 152 - sa1100 Files specific to Intel StrongARM SA1100 CPUs 153- disk Code for disk drive partition handling 154- doc Documentation (don't expect too much) 155- drivers Commonly used device drivers 156- dtt Digital Thermometer and Thermostat drivers 157- examples Example code for standalone applications, etc. 158- include Header Files 159- lib_arm Files generic to ARM architecture 160- lib_avr32 Files generic to AVR32 architecture 161- lib_generic Files generic to all architectures 162- lib_i386 Files generic to i386 architecture 163- lib_m68k Files generic to m68k architecture 164- lib_mips Files generic to MIPS architecture 165- lib_nios Files generic to NIOS architecture 166- lib_ppc Files generic to PowerPC architecture 167- libfdt Library files to support flattened device trees 168- net Networking code 169- post Power On Self Test 170- rtc Real Time Clock drivers 171- tools Tools to build S-Record or U-Boot images, etc. 172 173Software Configuration: 174======================= 175 176Configuration is usually done using C preprocessor defines; the 177rationale behind that is to avoid dead code whenever possible. 178 179There are two classes of configuration variables: 180 181* Configuration _OPTIONS_: 182 These are selectable by the user and have names beginning with 183 "CONFIG_". 184 185* Configuration _SETTINGS_: 186 These depend on the hardware etc. and should not be meddled with if 187 you don't know what you're doing; they have names beginning with 188 "CFG_". 189 190Later we will add a configuration tool - probably similar to or even 191identical to what's used for the Linux kernel. Right now, we have to 192do the configuration by hand, which means creating some symbolic 193links and editing some configuration files. We use the TQM8xxL boards 194as an example here. 195 196 197Selection of Processor Architecture and Board Type: 198--------------------------------------------------- 199 200For all supported boards there are ready-to-use default 201configurations available; just type "make <board_name>_config". 202 203Example: For a TQM823L module type: 204 205 cd u-boot 206 make TQM823L_config 207 208For the Cogent platform, you need to specify the cpu type as well; 209e.g. "make cogent_mpc8xx_config". And also configure the cogent 210directory according to the instructions in cogent/README. 211 212 213Configuration Options: 214---------------------- 215 216Configuration depends on the combination of board and CPU type; all 217such information is kept in a configuration file 218"include/configs/<board_name>.h". 219 220Example: For a TQM823L module, all configuration settings are in 221"include/configs/TQM823L.h". 222 223 224Many of the options are named exactly as the corresponding Linux 225kernel configuration options. The intention is to make it easier to 226build a config tool - later. 227 228 229The following options need to be configured: 230 231- CPU Type: Define exactly one of 232 233 PowerPC based CPUs: 234 ------------------- 235 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860 236 or CONFIG_MPC5xx 237 or CONFIG_MPC8220 238 or CONFIG_MPC824X, CONFIG_MPC8260 239 or CONFIG_MPC85xx 240 or CONFIG_IOP480 241 or CONFIG_405GP 242 or CONFIG_405EP 243 or CONFIG_440 244 or CONFIG_MPC74xx 245 or CONFIG_750FX 246 247 ARM based CPUs: 248 --------------- 249 CONFIG_SA1110 250 CONFIG_ARM7 251 CONFIG_PXA250 252 CONFIG_CPU_MONAHANS 253 254 MicroBlaze based CPUs: 255 ---------------------- 256 CONFIG_MICROBLAZE 257 258 Nios-2 based CPUs: 259 ---------------------- 260 CONFIG_NIOS2 261 262 AVR32 based CPUs: 263 ---------------------- 264 CONFIG_AT32AP 265 266- Board Type: Define exactly one of 267 268 PowerPC based boards: 269 --------------------- 270 271 CONFIG_ADCIOP CONFIG_FPS860L CONFIG_OXC 272 CONFIG_ADS860 CONFIG_GEN860T CONFIG_PCI405 273 CONFIG_AMX860 CONFIG_GENIETV CONFIG_PCIPPC2 274 CONFIG_AP1000 CONFIG_GTH CONFIG_PCIPPC6 275 CONFIG_AR405 CONFIG_gw8260 CONFIG_pcu_e 276 CONFIG_BAB7xx CONFIG_hermes CONFIG_PIP405 277 CONFIG_BC3450 CONFIG_hymod CONFIG_PM826 278 CONFIG_c2mon CONFIG_IAD210 CONFIG_ppmc8260 279 CONFIG_CANBT CONFIG_ICU862 CONFIG_QS823 280 CONFIG_CCM CONFIG_IP860 CONFIG_QS850 281 CONFIG_CMI CONFIG_IPHASE4539 CONFIG_QS860T 282 CONFIG_cogent_mpc8260 CONFIG_IVML24 CONFIG_RBC823 283 CONFIG_cogent_mpc8xx CONFIG_IVML24_128 CONFIG_RPXClassic 284 CONFIG_CPCI405 CONFIG_IVML24_256 CONFIG_RPXlite 285 CONFIG_CPCI4052 CONFIG_IVMS8 CONFIG_RPXsuper 286 CONFIG_CPCIISER4 CONFIG_IVMS8_128 CONFIG_rsdproto 287 CONFIG_CPU86 CONFIG_IVMS8_256 CONFIG_sacsng 288 CONFIG_CRAYL1 CONFIG_JSE CONFIG_Sandpoint8240 289 CONFIG_CSB272 CONFIG_LANTEC CONFIG_Sandpoint8245 290 CONFIG_CU824 CONFIG_LITE5200B CONFIG_sbc8260 291 CONFIG_DASA_SIM CONFIG_lwmon CONFIG_sbc8560 292 CONFIG_DB64360 CONFIG_MBX CONFIG_SM850 293 CONFIG_DB64460 CONFIG_MBX860T CONFIG_SPD823TS 294 CONFIG_DU405 CONFIG_MHPC CONFIG_STXGP3 295 CONFIG_DUET_ADS CONFIG_MIP405 CONFIG_SXNI855T 296 CONFIG_EBONY CONFIG_MOUSSE CONFIG_TQM823L 297 CONFIG_ELPPC CONFIG_MPC8260ADS CONFIG_TQM8260 298 CONFIG_ELPT860 CONFIG_MPC8540ADS CONFIG_TQM850L 299 CONFIG_ep8260 CONFIG_MPC8540EVAL CONFIG_TQM855L 300 CONFIG_ERIC CONFIG_MPC8560ADS CONFIG_TQM860L 301 CONFIG_ESTEEM192E CONFIG_MUSENKI CONFIG_TTTech 302 CONFIG_ETX094 CONFIG_MVS1 CONFIG_UTX8245 303 CONFIG_EVB64260 CONFIG_NETPHONE CONFIG_V37 304 CONFIG_FADS823 CONFIG_NETTA CONFIG_W7OLMC 305 CONFIG_FADS850SAR CONFIG_NETVIA CONFIG_W7OLMG 306 CONFIG_FADS860T CONFIG_NX823 CONFIG_WALNUT 307 CONFIG_FLAGADM CONFIG_OCRTC CONFIG_ZPC1900 308 CONFIG_FPS850L CONFIG_ORSG CONFIG_ZUMA 309 310 ARM based boards: 311 ----------------- 312 313 CONFIG_ARMADILLO, CONFIG_AT91RM9200DK, CONFIG_CERF250, 314 CONFIG_CSB637, CONFIG_DELTA, CONFIG_DNP1110, 315 CONFIG_EP7312, CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE, 316 CONFIG_IMPA7, CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, 317 CONFIG_KB9202, CONFIG_LART, CONFIG_LPD7A400, 318 CONFIG_LUBBOCK, CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4, 319 CONFIG_PLEB2, CONFIG_SHANNON, CONFIG_P2_OMAP730, 320 CONFIG_SMDK2400, CONFIG_SMDK2410, CONFIG_TRAB, 321 CONFIG_VCMA9 322 323 MicroBlaze based boards: 324 ------------------------ 325 326 CONFIG_SUZAKU 327 328 Nios-2 based boards: 329 ------------------------ 330 331 CONFIG_PCI5441 CONFIG_PK1C20 332 CONFIG_EP1C20 CONFIG_EP1S10 CONFIG_EP1S40 333 334 AVR32 based boards: 335 ------------------- 336 337 CONFIG_ATSTK1000 338 339- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 340 Define exactly one of 341 CONFIG_ATSTK1002 342 343 344- CPU Module Type: (if CONFIG_COGENT is defined) 345 Define exactly one of 346 CONFIG_CMA286_60_OLD 347--- FIXME --- not tested yet: 348 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 349 CONFIG_CMA287_23, CONFIG_CMA287_50 350 351- Motherboard Type: (if CONFIG_COGENT is defined) 352 Define exactly one of 353 CONFIG_CMA101, CONFIG_CMA102 354 355- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 356 Define one or more of 357 CONFIG_CMA302 358 359- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 360 Define one or more of 361 CONFIG_LCD_HEARTBEAT - update a character position on 362 the lcd display every second with 363 a "rotator" |\-/|\-/ 364 365- Board flavour: (if CONFIG_MPC8260ADS is defined) 366 CONFIG_ADSTYPE 367 Possible values are: 368 CFG_8260ADS - original MPC8260ADS 369 CFG_8266ADS - MPC8266ADS 370 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 371 CFG_8272ADS - MPC8272ADS 372 373- MPC824X Family Member (if CONFIG_MPC824X is defined) 374 Define exactly one of 375 CONFIG_MPC8240, CONFIG_MPC8245 376 377- 8xx CPU Options: (if using an MPC8xx cpu) 378 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 379 get_gclk_freq() cannot work 380 e.g. if there is no 32KHz 381 reference PIT/RTC clock 382 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 383 or XTAL/EXTAL) 384 385- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 386 CFG_8xx_CPUCLK_MIN 387 CFG_8xx_CPUCLK_MAX 388 CONFIG_8xx_CPUCLK_DEFAULT 389 See doc/README.MPC866 390 391 CFG_MEASURE_CPUCLK 392 393 Define this to measure the actual CPU clock instead 394 of relying on the correctness of the configured 395 values. Mostly useful for board bringup to make sure 396 the PLL is locked at the intended frequency. Note 397 that this requires a (stable) reference clock (32 kHz 398 RTC clock or CFG_8XX_XIN) 399 400- Intel Monahans options: 401 CFG_MONAHANS_RUN_MODE_OSC_RATIO 402 403 Defines the Monahans run mode to oscillator 404 ratio. Valid values are 8, 16, 24, 31. The core 405 frequency is this value multiplied by 13 MHz. 406 407 CFG_MONAHANS_TURBO_RUN_MODE_RATIO 408 409 Defines the Monahans turbo mode to oscillator 410 ratio. Valid values are 1 (default if undefined) and 411 2. The core frequency as calculated above is multiplied 412 by this value. 413 414- Linux Kernel Interface: 415 CONFIG_CLOCKS_IN_MHZ 416 417 U-Boot stores all clock information in Hz 418 internally. For binary compatibility with older Linux 419 kernels (which expect the clocks passed in the 420 bd_info data to be in MHz) the environment variable 421 "clocks_in_mhz" can be defined so that U-Boot 422 converts clock data to MHZ before passing it to the 423 Linux kernel. 424 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 425 "clocks_in_mhz=1" is automatically included in the 426 default environment. 427 428 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 429 430 When transfering memsize parameter to linux, some versions 431 expect it to be in bytes, others in MB. 432 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 433 434 CONFIG_OF_LIBFDT / CONFIG_OF_FLAT_TREE 435 436 New kernel versions are expecting firmware settings to be 437 passed using flattened device trees (based on open firmware 438 concepts). 439 440 CONFIG_OF_LIBFDT 441 * New libfdt-based support 442 * Adds the "fdt" command 443 * The bootm command does _not_ modify the fdt 444 445 CONFIG_OF_FLAT_TREE 446 * Deprecated, see CONFIG_OF_LIBFDT 447 * Original ft_build.c-based support 448 * Automatically modifies the dft as part of the bootm command 449 * The environment variable "disable_of", when set, 450 disables this functionality. 451 452 CONFIG_OF_FLAT_TREE_MAX_SIZE 453 454 The maximum size of the constructed OF tree. 455 456 OF_CPU - The proper name of the cpus node. 457 OF_SOC - The proper name of the soc node. 458 OF_TBCLK - The timebase frequency. 459 OF_STDOUT_PATH - The path to the console device 460 461 CONFIG_OF_HAS_BD_T 462 463 * CONFIG_OF_LIBFDT - enables the "fdt bd_t" command 464 * CONFIG_OF_FLAT_TREE - The resulting flat device tree 465 will have a copy of the bd_t. Space should be 466 pre-allocated in the dts for the bd_t. 467 468 CONFIG_OF_HAS_UBOOT_ENV 469 470 * CONFIG_OF_LIBFDT - enables the "fdt bd_t" command 471 * CONFIG_OF_FLAT_TREE - The resulting flat device tree 472 will have a copy of u-boot's environment variables 473 474 CONFIG_OF_BOARD_SETUP 475 476 Board code has addition modification that it wants to make 477 to the flat device tree before handing it off to the kernel 478 479 CONFIG_OF_BOOT_CPU 480 481 This define fills in the correct boot cpu in the boot 482 param header, the default value is zero if undefined. 483 484- Serial Ports: 485 CFG_PL010_SERIAL 486 487 Define this if you want support for Amba PrimeCell PL010 UARTs. 488 489 CFG_PL011_SERIAL 490 491 Define this if you want support for Amba PrimeCell PL011 UARTs. 492 493 CONFIG_PL011_CLOCK 494 495 If you have Amba PrimeCell PL011 UARTs, set this variable to 496 the clock speed of the UARTs. 497 498 CONFIG_PL01x_PORTS 499 500 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 501 define this to a list of base addresses for each (supported) 502 port. See e.g. include/configs/versatile.h 503 504 505- Console Interface: 506 Depending on board, define exactly one serial port 507 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 508 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 509 console by defining CONFIG_8xx_CONS_NONE 510 511 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 512 port routines must be defined elsewhere 513 (i.e. serial_init(), serial_getc(), ...) 514 515 CONFIG_CFB_CONSOLE 516 Enables console device for a color framebuffer. Needs following 517 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 518 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 519 (default big endian) 520 VIDEO_HW_RECTFILL graphic chip supports 521 rectangle fill 522 (cf. smiLynxEM) 523 VIDEO_HW_BITBLT graphic chip supports 524 bit-blit (cf. smiLynxEM) 525 VIDEO_VISIBLE_COLS visible pixel columns 526 (cols=pitch) 527 VIDEO_VISIBLE_ROWS visible pixel rows 528 VIDEO_PIXEL_SIZE bytes per pixel 529 VIDEO_DATA_FORMAT graphic data format 530 (0-5, cf. cfb_console.c) 531 VIDEO_FB_ADRS framebuffer address 532 VIDEO_KBD_INIT_FCT keyboard int fct 533 (i.e. i8042_kbd_init()) 534 VIDEO_TSTC_FCT test char fct 535 (i.e. i8042_tstc) 536 VIDEO_GETC_FCT get char fct 537 (i.e. i8042_getc) 538 CONFIG_CONSOLE_CURSOR cursor drawing on/off 539 (requires blink timer 540 cf. i8042.c) 541 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 542 CONFIG_CONSOLE_TIME display time/date info in 543 upper right corner 544 (requires CFG_CMD_DATE) 545 CONFIG_VIDEO_LOGO display Linux logo in 546 upper left corner 547 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 548 linux_logo.h for logo. 549 Requires CONFIG_VIDEO_LOGO 550 CONFIG_CONSOLE_EXTRA_INFO 551 addional board info beside 552 the logo 553 554 When CONFIG_CFB_CONSOLE is defined, video console is 555 default i/o. Serial console can be forced with 556 environment 'console=serial'. 557 558 When CONFIG_SILENT_CONSOLE is defined, all console 559 messages (by U-Boot and Linux!) can be silenced with 560 the "silent" environment variable. See 561 doc/README.silent for more information. 562 563- Console Baudrate: 564 CONFIG_BAUDRATE - in bps 565 Select one of the baudrates listed in 566 CFG_BAUDRATE_TABLE, see below. 567 CFG_BRGCLK_PRESCALE, baudrate prescale 568 569- Interrupt driven serial port input: 570 CONFIG_SERIAL_SOFTWARE_FIFO 571 572 PPC405GP only. 573 Use an interrupt handler for receiving data on the 574 serial port. It also enables using hardware handshake 575 (RTS/CTS) and UART's built-in FIFO. Set the number of 576 bytes the interrupt driven input buffer should have. 577 578 Leave undefined to disable this feature, including 579 disable the buffer and hardware handshake. 580 581- Console UART Number: 582 CONFIG_UART1_CONSOLE 583 584 AMCC PPC4xx only. 585 If defined internal UART1 (and not UART0) is used 586 as default U-Boot console. 587 588- Boot Delay: CONFIG_BOOTDELAY - in seconds 589 Delay before automatically booting the default image; 590 set to -1 to disable autoboot. 591 592 See doc/README.autoboot for these options that 593 work with CONFIG_BOOTDELAY. None are required. 594 CONFIG_BOOT_RETRY_TIME 595 CONFIG_BOOT_RETRY_MIN 596 CONFIG_AUTOBOOT_KEYED 597 CONFIG_AUTOBOOT_PROMPT 598 CONFIG_AUTOBOOT_DELAY_STR 599 CONFIG_AUTOBOOT_STOP_STR 600 CONFIG_AUTOBOOT_DELAY_STR2 601 CONFIG_AUTOBOOT_STOP_STR2 602 CONFIG_ZERO_BOOTDELAY_CHECK 603 CONFIG_RESET_TO_RETRY 604 605- Autoboot Command: 606 CONFIG_BOOTCOMMAND 607 Only needed when CONFIG_BOOTDELAY is enabled; 608 define a command string that is automatically executed 609 when no character is read on the console interface 610 within "Boot Delay" after reset. 611 612 CONFIG_BOOTARGS 613 This can be used to pass arguments to the bootm 614 command. The value of CONFIG_BOOTARGS goes into the 615 environment value "bootargs". 616 617 CONFIG_RAMBOOT and CONFIG_NFSBOOT 618 The value of these goes into the environment as 619 "ramboot" and "nfsboot" respectively, and can be used 620 as a convenience, when switching between booting from 621 ram and nfs. 622 623- Pre-Boot Commands: 624 CONFIG_PREBOOT 625 626 When this option is #defined, the existence of the 627 environment variable "preboot" will be checked 628 immediately before starting the CONFIG_BOOTDELAY 629 countdown and/or running the auto-boot command resp. 630 entering interactive mode. 631 632 This feature is especially useful when "preboot" is 633 automatically generated or modified. For an example 634 see the LWMON board specific code: here "preboot" is 635 modified when the user holds down a certain 636 combination of keys on the (special) keyboard when 637 booting the systems 638 639- Serial Download Echo Mode: 640 CONFIG_LOADS_ECHO 641 If defined to 1, all characters received during a 642 serial download (using the "loads" command) are 643 echoed back. This might be needed by some terminal 644 emulations (like "cu"), but may as well just take 645 time on others. This setting #define's the initial 646 value of the "loads_echo" environment variable. 647 648- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined) 649 CONFIG_KGDB_BAUDRATE 650 Select one of the baudrates listed in 651 CFG_BAUDRATE_TABLE, see below. 652 653- Monitor Functions: 654 CONFIG_COMMANDS 655 Most monitor functions can be selected (or 656 de-selected) by adjusting the definition of 657 CONFIG_COMMANDS; to select individual functions, 658 #define CONFIG_COMMANDS by "OR"ing any of the 659 following values: 660 661 #define enables commands: 662 ------------------------- 663 CFG_CMD_ASKENV * ask for env variable 664 CFG_CMD_AUTOSCRIPT Autoscript Support 665 CFG_CMD_BDI bdinfo 666 CFG_CMD_BEDBUG * Include BedBug Debugger 667 CFG_CMD_BMP * BMP support 668 CFG_CMD_BSP * Board specific commands 669 CFG_CMD_BOOTD bootd 670 CFG_CMD_CACHE * icache, dcache 671 CFG_CMD_CONSOLE coninfo 672 CFG_CMD_DATE * support for RTC, date/time... 673 CFG_CMD_DHCP * DHCP support 674 CFG_CMD_DIAG * Diagnostics 675 CFG_CMD_DOC * Disk-On-Chip Support 676 CFG_CMD_DTT * Digital Therm and Thermostat 677 CFG_CMD_ECHO echo arguments 678 CFG_CMD_EEPROM * EEPROM read/write support 679 CFG_CMD_ELF * bootelf, bootvx 680 CFG_CMD_ENV saveenv 681 CFG_CMD_FDC * Floppy Disk Support 682 CFG_CMD_FAT * FAT partition support 683 CFG_CMD_FDOS * Dos diskette Support 684 CFG_CMD_FLASH flinfo, erase, protect 685 CFG_CMD_FPGA FPGA device initialization support 686 CFG_CMD_HWFLOW * RTS/CTS hw flow control 687 CFG_CMD_I2C * I2C serial bus support 688 CFG_CMD_IDE * IDE harddisk support 689 CFG_CMD_IMI iminfo 690 CFG_CMD_IMLS List all found images 691 CFG_CMD_IMMAP * IMMR dump support 692 CFG_CMD_IRQ * irqinfo 693 CFG_CMD_ITEST Integer/string test of 2 values 694 CFG_CMD_JFFS2 * JFFS2 Support 695 CFG_CMD_KGDB * kgdb 696 CFG_CMD_LOADB loadb 697 CFG_CMD_LOADS loads 698 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 699 loop, loopw, mtest 700 CFG_CMD_MISC Misc functions like sleep etc 701 CFG_CMD_MMC * MMC memory mapped support 702 CFG_CMD_MII * MII utility commands 703 CFG_CMD_NAND * NAND support 704 CFG_CMD_NET bootp, tftpboot, rarpboot 705 CFG_CMD_PCI * pciinfo 706 CFG_CMD_PCMCIA * PCMCIA support 707 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host 708 CFG_CMD_PORTIO * Port I/O 709 CFG_CMD_REGINFO * Register dump 710 CFG_CMD_RUN run command in env variable 711 CFG_CMD_SAVES * save S record dump 712 CFG_CMD_SCSI * SCSI Support 713 CFG_CMD_SDRAM * print SDRAM configuration information 714 (requires CFG_CMD_I2C) 715 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only) 716 CFG_CMD_SPI * SPI serial bus support 717 CFG_CMD_USB * USB support 718 CFG_CMD_VFD * VFD support (TRAB) 719 CFG_CMD_BSP * Board SPecific functions 720 CFG_CMD_CDP * Cisco Discover Protocol support 721 ----------------------------------------------- 722 CFG_CMD_ALL all 723 724 CONFIG_CMD_DFL Default configuration; at the moment 725 this is includes all commands, except 726 the ones marked with "*" in the list 727 above. 728 729 If you don't define CONFIG_COMMANDS it defaults to 730 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can 731 override the default settings in the respective 732 include file. 733 734 EXAMPLE: If you want all functions except of network 735 support you can write: 736 737 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET) 738 739 Other Commands: 740 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 741 742 Note: Don't enable the "icache" and "dcache" commands 743 (configuration option CFG_CMD_CACHE) unless you know 744 what you (and your U-Boot users) are doing. Data 745 cache cannot be enabled on systems like the 8xx or 746 8260 (where accesses to the IMMR region must be 747 uncached), and it cannot be disabled on all other 748 systems where we (mis-) use the data cache to hold an 749 initial stack and some data. 750 751 752 XXX - this list needs to get updated! 753 754- Watchdog: 755 CONFIG_WATCHDOG 756 If this variable is defined, it enables watchdog 757 support. There must be support in the platform specific 758 code for a watchdog. For the 8xx and 8260 CPUs, the 759 SIU Watchdog feature is enabled in the SYPCR 760 register. 761 762- U-Boot Version: 763 CONFIG_VERSION_VARIABLE 764 If this variable is defined, an environment variable 765 named "ver" is created by U-Boot showing the U-Boot 766 version as printed by the "version" command. 767 This variable is readonly. 768 769- Real-Time Clock: 770 771 When CFG_CMD_DATE is selected, the type of the RTC 772 has to be selected, too. Define exactly one of the 773 following options: 774 775 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 776 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 777 CONFIG_RTC_MC146818 - use MC146818 RTC 778 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 779 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 780 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 781 CONFIG_RTC_DS164x - use Dallas DS164x RTC 782 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 783 784 Note that if the RTC uses I2C, then the I2C interface 785 must also be configured. See I2C Support, below. 786 787- Timestamp Support: 788 789 When CONFIG_TIMESTAMP is selected, the timestamp 790 (date and time) of an image is printed by image 791 commands like bootm or iminfo. This option is 792 automatically enabled when you select CFG_CMD_DATE . 793 794- Partition Support: 795 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 796 and/or CONFIG_ISO_PARTITION 797 798 If IDE or SCSI support is enabled (CFG_CMD_IDE or 799 CFG_CMD_SCSI) you must configure support for at least 800 one partition type as well. 801 802- IDE Reset method: 803 CONFIG_IDE_RESET_ROUTINE - this is defined in several 804 board configurations files but used nowhere! 805 806 CONFIG_IDE_RESET - is this is defined, IDE Reset will 807 be performed by calling the function 808 ide_set_reset(int reset) 809 which has to be defined in a board specific file 810 811- ATAPI Support: 812 CONFIG_ATAPI 813 814 Set this to enable ATAPI support. 815 816- LBA48 Support 817 CONFIG_LBA48 818 819 Set this to enable support for disks larger than 137GB 820 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL 821 Whithout these , LBA48 support uses 32bit variables and will 'only' 822 support disks up to 2.1TB. 823 824 CFG_64BIT_LBA: 825 When enabled, makes the IDE subsystem use 64bit sector addresses. 826 Default is 32bit. 827 828- SCSI Support: 829 At the moment only there is only support for the 830 SYM53C8XX SCSI controller; define 831 CONFIG_SCSI_SYM53C8XX to enable it. 832 833 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 834 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 835 CFG_SCSI_MAX_LUN] can be adjusted to define the 836 maximum numbers of LUNs, SCSI ID's and target 837 devices. 838 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 839 840- NETWORK Support (PCI): 841 CONFIG_E1000 842 Support for Intel 8254x gigabit chips. 843 844 CONFIG_EEPRO100 845 Support for Intel 82557/82559/82559ER chips. 846 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 847 write routine for first time initialisation. 848 849 CONFIG_TULIP 850 Support for Digital 2114x chips. 851 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 852 modem chip initialisation (KS8761/QS6611). 853 854 CONFIG_NATSEMI 855 Support for National dp83815 chips. 856 857 CONFIG_NS8382X 858 Support for National dp8382[01] gigabit chips. 859 860- NETWORK Support (other): 861 862 CONFIG_DRIVER_LAN91C96 863 Support for SMSC's LAN91C96 chips. 864 865 CONFIG_LAN91C96_BASE 866 Define this to hold the physical address 867 of the LAN91C96's I/O space 868 869 CONFIG_LAN91C96_USE_32_BIT 870 Define this to enable 32 bit addressing 871 872 CONFIG_DRIVER_SMC91111 873 Support for SMSC's LAN91C111 chip 874 875 CONFIG_SMC91111_BASE 876 Define this to hold the physical address 877 of the device (I/O space) 878 879 CONFIG_SMC_USE_32_BIT 880 Define this if data bus is 32 bits 881 882 CONFIG_SMC_USE_IOFUNCS 883 Define this to use i/o functions instead of macros 884 (some hardware wont work with macros) 885 886- USB Support: 887 At the moment only the UHCI host controller is 888 supported (PIP405, MIP405, MPC5200); define 889 CONFIG_USB_UHCI to enable it. 890 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 891 and define CONFIG_USB_STORAGE to enable the USB 892 storage devices. 893 Note: 894 Supported are USB Keyboards and USB Floppy drives 895 (TEAC FD-05PUB). 896 MPC5200 USB requires additional defines: 897 CONFIG_USB_CLOCK 898 for 528 MHz Clock: 0x0001bbbb 899 CONFIG_USB_CONFIG 900 for differential drivers: 0x00001000 901 for single ended drivers: 0x00005000 902 903 904- MMC Support: 905 The MMC controller on the Intel PXA is supported. To 906 enable this define CONFIG_MMC. The MMC can be 907 accessed from the boot prompt by mapping the device 908 to physical memory similar to flash. Command line is 909 enabled with CFG_CMD_MMC. The MMC driver also works with 910 the FAT fs. This is enabled with CFG_CMD_FAT. 911 912- Journaling Flash filesystem support: 913 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 914 CONFIG_JFFS2_NAND_DEV 915 Define these for a default partition on a NAND device 916 917 CFG_JFFS2_FIRST_SECTOR, 918 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS 919 Define these for a default partition on a NOR device 920 921 CFG_JFFS_CUSTOM_PART 922 Define this to create an own partition. You have to provide a 923 function struct part_info* jffs2_part_info(int part_num) 924 925 If you define only one JFFS2 partition you may also want to 926 #define CFG_JFFS_SINGLE_PART 1 927 to disable the command chpart. This is the default when you 928 have not defined a custom partition 929 930- Keyboard Support: 931 CONFIG_ISA_KEYBOARD 932 933 Define this to enable standard (PC-Style) keyboard 934 support 935 936 CONFIG_I8042_KBD 937 Standard PC keyboard driver with US (is default) and 938 GERMAN key layout (switch via environment 'keymap=de') support. 939 Export function i8042_kbd_init, i8042_tstc and i8042_getc 940 for cfb_console. Supports cursor blinking. 941 942- Video support: 943 CONFIG_VIDEO 944 945 Define this to enable video support (for output to 946 video). 947 948 CONFIG_VIDEO_CT69000 949 950 Enable Chips & Technologies 69000 Video chip 951 952 CONFIG_VIDEO_SMI_LYNXEM 953 Enable Silicon Motion SMI 712/710/810 Video chip. The 954 video output is selected via environment 'videoout' 955 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 956 assumed. 957 958 For the CT69000 and SMI_LYNXEM drivers, videomode is 959 selected via environment 'videomode'. Two diferent ways 960 are possible: 961 - "videomode=num" 'num' is a standard LiLo mode numbers. 962 Following standard modes are supported (* is default): 963 964 Colors 640x480 800x600 1024x768 1152x864 1280x1024 965 -------------+--------------------------------------------- 966 8 bits | 0x301* 0x303 0x305 0x161 0x307 967 15 bits | 0x310 0x313 0x316 0x162 0x319 968 16 bits | 0x311 0x314 0x317 0x163 0x31A 969 24 bits | 0x312 0x315 0x318 ? 0x31B 970 -------------+--------------------------------------------- 971 (i.e. setenv videomode 317; saveenv; reset;) 972 973 - "videomode=bootargs" all the video parameters are parsed 974 from the bootargs. (See drivers/videomodes.c) 975 976 977 CONFIG_VIDEO_SED13806 978 Enable Epson SED13806 driver. This driver supports 8bpp 979 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 980 or CONFIG_VIDEO_SED13806_16BPP 981 982- Keyboard Support: 983 CONFIG_KEYBOARD 984 985 Define this to enable a custom keyboard support. 986 This simply calls drv_keyboard_init() which must be 987 defined in your board-specific files. 988 The only board using this so far is RBC823. 989 990- LCD Support: CONFIG_LCD 991 992 Define this to enable LCD support (for output to LCD 993 display); also select one of the supported displays 994 by defining one of these: 995 996 CONFIG_NEC_NL6448AC33: 997 998 NEC NL6448AC33-18. Active, color, single scan. 999 1000 CONFIG_NEC_NL6448BC20 1001 1002 NEC NL6448BC20-08. 6.5", 640x480. 1003 Active, color, single scan. 1004 1005 CONFIG_NEC_NL6448BC33_54 1006 1007 NEC NL6448BC33-54. 10.4", 640x480. 1008 Active, color, single scan. 1009 1010 CONFIG_SHARP_16x9 1011 1012 Sharp 320x240. Active, color, single scan. 1013 It isn't 16x9, and I am not sure what it is. 1014 1015 CONFIG_SHARP_LQ64D341 1016 1017 Sharp LQ64D341 display, 640x480. 1018 Active, color, single scan. 1019 1020 CONFIG_HLD1045 1021 1022 HLD1045 display, 640x480. 1023 Active, color, single scan. 1024 1025 CONFIG_OPTREX_BW 1026 1027 Optrex CBL50840-2 NF-FW 99 22 M5 1028 or 1029 Hitachi LMG6912RPFC-00T 1030 or 1031 Hitachi SP14Q002 1032 1033 320x240. Black & white. 1034 1035 Normally display is black on white background; define 1036 CFG_WHITE_ON_BLACK to get it inverted. 1037 1038- Splash Screen Support: CONFIG_SPLASH_SCREEN 1039 1040 If this option is set, the environment is checked for 1041 a variable "splashimage". If found, the usual display 1042 of logo, copyright and system information on the LCD 1043 is suppressed and the BMP image at the address 1044 specified in "splashimage" is loaded instead. The 1045 console is redirected to the "nulldev", too. This 1046 allows for a "silent" boot where a splash screen is 1047 loaded very quickly after power-on. 1048 1049- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1050 1051 If this option is set, additionally to standard BMP 1052 images, gzipped BMP images can be displayed via the 1053 splashscreen support or the bmp command. 1054 1055- Compression support: 1056 CONFIG_BZIP2 1057 1058 If this option is set, support for bzip2 compressed 1059 images is included. If not, only uncompressed and gzip 1060 compressed images are supported. 1061 1062 NOTE: the bzip2 algorithm requires a lot of RAM, so 1063 the malloc area (as defined by CFG_MALLOC_LEN) should 1064 be at least 4MB. 1065 1066- MII/PHY support: 1067 CONFIG_PHY_ADDR 1068 1069 The address of PHY on MII bus. 1070 1071 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1072 1073 The clock frequency of the MII bus 1074 1075 CONFIG_PHY_GIGE 1076 1077 If this option is set, support for speed/duplex 1078 detection of Gigabit PHY is included. 1079 1080 CONFIG_PHY_RESET_DELAY 1081 1082 Some PHY like Intel LXT971A need extra delay after 1083 reset before any MII register access is possible. 1084 For such PHY, set this option to the usec delay 1085 required. (minimum 300usec for LXT971A) 1086 1087 CONFIG_PHY_CMD_DELAY (ppc4xx) 1088 1089 Some PHY like Intel LXT971A need extra delay after 1090 command issued before MII status register can be read 1091 1092- Ethernet address: 1093 CONFIG_ETHADDR 1094 CONFIG_ETH2ADDR 1095 CONFIG_ETH3ADDR 1096 1097 Define a default value for ethernet address to use 1098 for the respective ethernet interface, in case this 1099 is not determined automatically. 1100 1101- IP address: 1102 CONFIG_IPADDR 1103 1104 Define a default value for the IP address to use for 1105 the default ethernet interface, in case this is not 1106 determined through e.g. bootp. 1107 1108- Server IP address: 1109 CONFIG_SERVERIP 1110 1111 Defines a default value for theIP address of a TFTP 1112 server to contact when using the "tftboot" command. 1113 1114- BOOTP Recovery Mode: 1115 CONFIG_BOOTP_RANDOM_DELAY 1116 1117 If you have many targets in a network that try to 1118 boot using BOOTP, you may want to avoid that all 1119 systems send out BOOTP requests at precisely the same 1120 moment (which would happen for instance at recovery 1121 from a power failure, when all systems will try to 1122 boot, thus flooding the BOOTP server. Defining 1123 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1124 inserted before sending out BOOTP requests. The 1125 following delays are insterted then: 1126 1127 1st BOOTP request: delay 0 ... 1 sec 1128 2nd BOOTP request: delay 0 ... 2 sec 1129 3rd BOOTP request: delay 0 ... 4 sec 1130 4th and following 1131 BOOTP requests: delay 0 ... 8 sec 1132 1133- DHCP Advanced Options: 1134 CONFIG_BOOTP_MASK 1135 1136 You can fine tune the DHCP functionality by adding 1137 these flags to the CONFIG_BOOTP_MASK define: 1138 1139 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1140 serverip from a DHCP server, it is possible that more 1141 than one DNS serverip is offered to the client. 1142 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1143 serverip will be stored in the additional environment 1144 variable "dnsip2". The first DNS serverip is always 1145 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1146 is added to the CONFIG_BOOTP_MASK. 1147 1148 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1149 to do a dynamic update of a DNS server. To do this, they 1150 need the hostname of the DHCP requester. 1151 If CONFIG_BOOP_SEND_HOSTNAME is added to the 1152 CONFIG_BOOTP_MASK, the content of the "hostname" 1153 environment variable is passed as option 12 to 1154 the DHCP server. 1155 1156 - CDP Options: 1157 CONFIG_CDP_DEVICE_ID 1158 1159 The device id used in CDP trigger frames. 1160 1161 CONFIG_CDP_DEVICE_ID_PREFIX 1162 1163 A two character string which is prefixed to the MAC address 1164 of the device. 1165 1166 CONFIG_CDP_PORT_ID 1167 1168 A printf format string which contains the ascii name of 1169 the port. Normally is set to "eth%d" which sets 1170 eth0 for the first ethernet, eth1 for the second etc. 1171 1172 CONFIG_CDP_CAPABILITIES 1173 1174 A 32bit integer which indicates the device capabilities; 1175 0x00000010 for a normal host which does not forwards. 1176 1177 CONFIG_CDP_VERSION 1178 1179 An ascii string containing the version of the software. 1180 1181 CONFIG_CDP_PLATFORM 1182 1183 An ascii string containing the name of the platform. 1184 1185 CONFIG_CDP_TRIGGER 1186 1187 A 32bit integer sent on the trigger. 1188 1189 CONFIG_CDP_POWER_CONSUMPTION 1190 1191 A 16bit integer containing the power consumption of the 1192 device in .1 of milliwatts. 1193 1194 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1195 1196 A byte containing the id of the VLAN. 1197 1198- Status LED: CONFIG_STATUS_LED 1199 1200 Several configurations allow to display the current 1201 status using a LED. For instance, the LED will blink 1202 fast while running U-Boot code, stop blinking as 1203 soon as a reply to a BOOTP request was received, and 1204 start blinking slow once the Linux kernel is running 1205 (supported by a status LED driver in the Linux 1206 kernel). Defining CONFIG_STATUS_LED enables this 1207 feature in U-Boot. 1208 1209- CAN Support: CONFIG_CAN_DRIVER 1210 1211 Defining CONFIG_CAN_DRIVER enables CAN driver support 1212 on those systems that support this (optional) 1213 feature, like the TQM8xxL modules. 1214 1215- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1216 1217 These enable I2C serial bus commands. Defining either of 1218 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1219 include the appropriate I2C driver for the selected cpu. 1220 1221 This will allow you to use i2c commands at the u-boot 1222 command line (as long as you set CFG_CMD_I2C in 1223 CONFIG_COMMANDS) and communicate with i2c based realtime 1224 clock chips. See common/cmd_i2c.c for a description of the 1225 command line interface. 1226 1227 CONFIG_I2C_CMD_TREE is a recommended option that places 1228 all I2C commands under a single 'i2c' root command. The 1229 older 'imm', 'imd', 'iprobe' etc. commands are considered 1230 deprecated and may disappear in the future. 1231 1232 CONFIG_HARD_I2C selects a hardware I2C controller. 1233 1234 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1235 bit-banging) driver instead of CPM or similar hardware 1236 support for I2C. 1237 1238 There are several other quantities that must also be 1239 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1240 1241 In both cases you will need to define CFG_I2C_SPEED 1242 to be the frequency (in Hz) at which you wish your i2c bus 1243 to run and CFG_I2C_SLAVE to be the address of this node (ie 1244 the cpu's i2c node address). 1245 1246 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1247 sets the cpu up as a master node and so its address should 1248 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1249 p.16-473). So, set CFG_I2C_SLAVE to 0. 1250 1251 That's all that's required for CONFIG_HARD_I2C. 1252 1253 If you use the software i2c interface (CONFIG_SOFT_I2C) 1254 then the following macros need to be defined (examples are 1255 from include/configs/lwmon.h): 1256 1257 I2C_INIT 1258 1259 (Optional). Any commands necessary to enable the I2C 1260 controller or configure ports. 1261 1262 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1263 1264 I2C_PORT 1265 1266 (Only for MPC8260 CPU). The I/O port to use (the code 1267 assumes both bits are on the same port). Valid values 1268 are 0..3 for ports A..D. 1269 1270 I2C_ACTIVE 1271 1272 The code necessary to make the I2C data line active 1273 (driven). If the data line is open collector, this 1274 define can be null. 1275 1276 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1277 1278 I2C_TRISTATE 1279 1280 The code necessary to make the I2C data line tri-stated 1281 (inactive). If the data line is open collector, this 1282 define can be null. 1283 1284 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1285 1286 I2C_READ 1287 1288 Code that returns TRUE if the I2C data line is high, 1289 FALSE if it is low. 1290 1291 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1292 1293 I2C_SDA(bit) 1294 1295 If <bit> is TRUE, sets the I2C data line high. If it 1296 is FALSE, it clears it (low). 1297 1298 eg: #define I2C_SDA(bit) \ 1299 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1300 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1301 1302 I2C_SCL(bit) 1303 1304 If <bit> is TRUE, sets the I2C clock line high. If it 1305 is FALSE, it clears it (low). 1306 1307 eg: #define I2C_SCL(bit) \ 1308 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1309 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1310 1311 I2C_DELAY 1312 1313 This delay is invoked four times per clock cycle so this 1314 controls the rate of data transfer. The data rate thus 1315 is 1 / (I2C_DELAY * 4). Often defined to be something 1316 like: 1317 1318 #define I2C_DELAY udelay(2) 1319 1320 CFG_I2C_INIT_BOARD 1321 1322 When a board is reset during an i2c bus transfer 1323 chips might think that the current transfer is still 1324 in progress. On some boards it is possible to access 1325 the i2c SCLK line directly, either by using the 1326 processor pin as a GPIO or by having a second pin 1327 connected to the bus. If this option is defined a 1328 custom i2c_init_board() routine in boards/xxx/board.c 1329 is run early in the boot sequence. 1330 1331 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1332 1333 This option enables configuration of bi_iic_fast[] flags 1334 in u-boot bd_info structure based on u-boot environment 1335 variable "i2cfast". (see also i2cfast) 1336 1337 CONFIG_I2C_MULTI_BUS 1338 1339 This option allows the use of multiple I2C buses, each of which 1340 must have a controller. At any point in time, only one bus is 1341 active. To switch to a different bus, use the 'i2c dev' command. 1342 Note that bus numbering is zero-based. 1343 1344 CFG_I2C_NOPROBES 1345 1346 This option specifies a list of I2C devices that will be skipped 1347 when the 'i2c probe' command is issued (or 'iprobe' using the legacy 1348 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device 1349 pairs. Otherwise, specify a 1D array of device addresses 1350 1351 e.g. 1352 #undef CONFIG_I2C_MULTI_BUS 1353 #define CFG_I2C_NOPROBES {0x50,0x68} 1354 1355 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1356 1357 #define CONFIG_I2C_MULTI_BUS 1358 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1359 1360 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1361 1362 CFG_SPD_BUS_NUM 1363 1364 If defined, then this indicates the I2C bus number for DDR SPD. 1365 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1366 1367 CFG_RTC_BUS_NUM 1368 1369 If defined, then this indicates the I2C bus number for the RTC. 1370 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1371 1372 CFG_DTT_BUS_NUM 1373 1374 If defined, then this indicates the I2C bus number for the DTT. 1375 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1376 1377 CONFIG_FSL_I2C 1378 1379 Define this option if you want to use Freescale's I2C driver in 1380 drivers/fsl_i2c.c. 1381 1382 1383- SPI Support: CONFIG_SPI 1384 1385 Enables SPI driver (so far only tested with 1386 SPI EEPROM, also an instance works with Crystal A/D and 1387 D/As on the SACSng board) 1388 1389 CONFIG_SPI_X 1390 1391 Enables extended (16-bit) SPI EEPROM addressing. 1392 (symmetrical to CONFIG_I2C_X) 1393 1394 CONFIG_SOFT_SPI 1395 1396 Enables a software (bit-bang) SPI driver rather than 1397 using hardware support. This is a general purpose 1398 driver that only requires three general I/O port pins 1399 (two outputs, one input) to function. If this is 1400 defined, the board configuration must define several 1401 SPI configuration items (port pins to use, etc). For 1402 an example, see include/configs/sacsng.h. 1403 1404- FPGA Support: CONFIG_FPGA_COUNT 1405 1406 Specify the number of FPGA devices to support. 1407 1408 CONFIG_FPGA 1409 1410 Used to specify the types of FPGA devices. For example, 1411 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 1412 1413 CFG_FPGA_PROG_FEEDBACK 1414 1415 Enable printing of hash marks during FPGA configuration. 1416 1417 CFG_FPGA_CHECK_BUSY 1418 1419 Enable checks on FPGA configuration interface busy 1420 status by the configuration function. This option 1421 will require a board or device specific function to 1422 be written. 1423 1424 CONFIG_FPGA_DELAY 1425 1426 If defined, a function that provides delays in the FPGA 1427 configuration driver. 1428 1429 CFG_FPGA_CHECK_CTRLC 1430 Allow Control-C to interrupt FPGA configuration 1431 1432 CFG_FPGA_CHECK_ERROR 1433 1434 Check for configuration errors during FPGA bitfile 1435 loading. For example, abort during Virtex II 1436 configuration if the INIT_B line goes low (which 1437 indicated a CRC error). 1438 1439 CFG_FPGA_WAIT_INIT 1440 1441 Maximum time to wait for the INIT_B line to deassert 1442 after PROB_B has been deasserted during a Virtex II 1443 FPGA configuration sequence. The default time is 500 1444 mS. 1445 1446 CFG_FPGA_WAIT_BUSY 1447 1448 Maximum time to wait for BUSY to deassert during 1449 Virtex II FPGA configuration. The default is 5 mS. 1450 1451 CFG_FPGA_WAIT_CONFIG 1452 1453 Time to wait after FPGA configuration. The default is 1454 200 mS. 1455 1456- Configuration Management: 1457 CONFIG_IDENT_STRING 1458 1459 If defined, this string will be added to the U-Boot 1460 version information (U_BOOT_VERSION) 1461 1462- Vendor Parameter Protection: 1463 1464 U-Boot considers the values of the environment 1465 variables "serial#" (Board Serial Number) and 1466 "ethaddr" (Ethernet Address) to be parameters that 1467 are set once by the board vendor / manufacturer, and 1468 protects these variables from casual modification by 1469 the user. Once set, these variables are read-only, 1470 and write or delete attempts are rejected. You can 1471 change this behviour: 1472 1473 If CONFIG_ENV_OVERWRITE is #defined in your config 1474 file, the write protection for vendor parameters is 1475 completely disabled. Anybody can change or delete 1476 these parameters. 1477 1478 Alternatively, if you #define _both_ CONFIG_ETHADDR 1479 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1480 ethernet address is installed in the environment, 1481 which can be changed exactly ONCE by the user. [The 1482 serial# is unaffected by this, i. e. it remains 1483 read-only.] 1484 1485- Protected RAM: 1486 CONFIG_PRAM 1487 1488 Define this variable to enable the reservation of 1489 "protected RAM", i. e. RAM which is not overwritten 1490 by U-Boot. Define CONFIG_PRAM to hold the number of 1491 kB you want to reserve for pRAM. You can overwrite 1492 this default value by defining an environment 1493 variable "pram" to the number of kB you want to 1494 reserve. Note that the board info structure will 1495 still show the full amount of RAM. If pRAM is 1496 reserved, a new environment variable "mem" will 1497 automatically be defined to hold the amount of 1498 remaining RAM in a form that can be passed as boot 1499 argument to Linux, for instance like that: 1500 1501 setenv bootargs ... mem=\${mem} 1502 saveenv 1503 1504 This way you can tell Linux not to use this memory, 1505 either, which results in a memory region that will 1506 not be affected by reboots. 1507 1508 *WARNING* If your board configuration uses automatic 1509 detection of the RAM size, you must make sure that 1510 this memory test is non-destructive. So far, the 1511 following board configurations are known to be 1512 "pRAM-clean": 1513 1514 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1515 HERMES, IP860, RPXlite, LWMON, LANTEC, 1516 PCU_E, FLAGADM, TQM8260 1517 1518- Error Recovery: 1519 CONFIG_PANIC_HANG 1520 1521 Define this variable to stop the system in case of a 1522 fatal error, so that you have to reset it manually. 1523 This is probably NOT a good idea for an embedded 1524 system where you want to system to reboot 1525 automatically as fast as possible, but it may be 1526 useful during development since you can try to debug 1527 the conditions that lead to the situation. 1528 1529 CONFIG_NET_RETRY_COUNT 1530 1531 This variable defines the number of retries for 1532 network operations like ARP, RARP, TFTP, or BOOTP 1533 before giving up the operation. If not defined, a 1534 default value of 5 is used. 1535 1536- Command Interpreter: 1537 CONFIG_AUTO_COMPLETE 1538 1539 Enable auto completion of commands using TAB. 1540 1541 Note that this feature has NOT been implemented yet 1542 for the "hush" shell. 1543 1544 1545 CFG_HUSH_PARSER 1546 1547 Define this variable to enable the "hush" shell (from 1548 Busybox) as command line interpreter, thus enabling 1549 powerful command line syntax like 1550 if...then...else...fi conditionals or `&&' and '||' 1551 constructs ("shell scripts"). 1552 1553 If undefined, you get the old, much simpler behaviour 1554 with a somewhat smaller memory footprint. 1555 1556 1557 CFG_PROMPT_HUSH_PS2 1558 1559 This defines the secondary prompt string, which is 1560 printed when the command interpreter needs more input 1561 to complete a command. Usually "> ". 1562 1563 Note: 1564 1565 In the current implementation, the local variables 1566 space and global environment variables space are 1567 separated. Local variables are those you define by 1568 simply typing `name=value'. To access a local 1569 variable later on, you have write `$name' or 1570 `${name}'; to execute the contents of a variable 1571 directly type `$name' at the command prompt. 1572 1573 Global environment variables are those you use 1574 setenv/printenv to work with. To run a command stored 1575 in such a variable, you need to use the run command, 1576 and you must not use the '$' sign to access them. 1577 1578 To store commands and special characters in a 1579 variable, please use double quotation marks 1580 surrounding the whole text of the variable, instead 1581 of the backslashes before semicolons and special 1582 symbols. 1583 1584- Commandline Editing and History: 1585 CONFIG_CMDLINE_EDITING 1586 1587 Enable editiong and History functions for interactive 1588 commandline input operations 1589 1590- Default Environment: 1591 CONFIG_EXTRA_ENV_SETTINGS 1592 1593 Define this to contain any number of null terminated 1594 strings (variable = value pairs) that will be part of 1595 the default environment compiled into the boot image. 1596 1597 For example, place something like this in your 1598 board's config file: 1599 1600 #define CONFIG_EXTRA_ENV_SETTINGS \ 1601 "myvar1=value1\0" \ 1602 "myvar2=value2\0" 1603 1604 Warning: This method is based on knowledge about the 1605 internal format how the environment is stored by the 1606 U-Boot code. This is NOT an official, exported 1607 interface! Although it is unlikely that this format 1608 will change soon, there is no guarantee either. 1609 You better know what you are doing here. 1610 1611 Note: overly (ab)use of the default environment is 1612 discouraged. Make sure to check other ways to preset 1613 the environment like the autoscript function or the 1614 boot command first. 1615 1616- DataFlash Support: 1617 CONFIG_HAS_DATAFLASH 1618 1619 Defining this option enables DataFlash features and 1620 allows to read/write in Dataflash via the standard 1621 commands cp, md... 1622 1623- SystemACE Support: 1624 CONFIG_SYSTEMACE 1625 1626 Adding this option adds support for Xilinx SystemACE 1627 chips attached via some sort of local bus. The address 1628 of the chip must alsh be defined in the 1629 CFG_SYSTEMACE_BASE macro. For example: 1630 1631 #define CONFIG_SYSTEMACE 1632 #define CFG_SYSTEMACE_BASE 0xf0000000 1633 1634 When SystemACE support is added, the "ace" device type 1635 becomes available to the fat commands, i.e. fatls. 1636 1637- TFTP Fixed UDP Port: 1638 CONFIG_TFTP_PORT 1639 1640 If this is defined, the environment variable tftpsrcp 1641 is used to supply the TFTP UDP source port value. 1642 If tftpsrcp isn't defined, the normal pseudo-random port 1643 number generator is used. 1644 1645 Also, the environment variable tftpdstp is used to supply 1646 the TFTP UDP destination port value. If tftpdstp isn't 1647 defined, the normal port 69 is used. 1648 1649 The purpose for tftpsrcp is to allow a TFTP server to 1650 blindly start the TFTP transfer using the pre-configured 1651 target IP address and UDP port. This has the effect of 1652 "punching through" the (Windows XP) firewall, allowing 1653 the remainder of the TFTP transfer to proceed normally. 1654 A better solution is to properly configure the firewall, 1655 but sometimes that is not allowed. 1656 1657- Show boot progress: 1658 CONFIG_SHOW_BOOT_PROGRESS 1659 1660 Defining this option allows to add some board- 1661 specific code (calling a user-provided function 1662 "show_boot_progress(int)") that enables you to show 1663 the system's boot progress on some display (for 1664 example, some LED's) on your board. At the moment, 1665 the following checkpoints are implemented: 1666 1667 Arg Where When 1668 1 common/cmd_bootm.c before attempting to boot an image 1669 -1 common/cmd_bootm.c Image header has bad magic number 1670 2 common/cmd_bootm.c Image header has correct magic number 1671 -2 common/cmd_bootm.c Image header has bad checksum 1672 3 common/cmd_bootm.c Image header has correct checksum 1673 -3 common/cmd_bootm.c Image data has bad checksum 1674 4 common/cmd_bootm.c Image data has correct checksum 1675 -4 common/cmd_bootm.c Image is for unsupported architecture 1676 5 common/cmd_bootm.c Architecture check OK 1677 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1678 6 common/cmd_bootm.c Image Type check OK 1679 -6 common/cmd_bootm.c gunzip uncompression error 1680 -7 common/cmd_bootm.c Unimplemented compression type 1681 7 common/cmd_bootm.c Uncompression OK 1682 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1683 8 common/cmd_bootm.c Image Type check OK 1684 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1685 9 common/cmd_bootm.c Start initial ramdisk verification 1686 -10 common/cmd_bootm.c Ramdisk header has bad magic number 1687 -11 common/cmd_bootm.c Ramdisk header has bad checksum 1688 10 common/cmd_bootm.c Ramdisk header is OK 1689 -12 common/cmd_bootm.c Ramdisk data has bad checksum 1690 11 common/cmd_bootm.c Ramdisk data has correct checksum 1691 12 common/cmd_bootm.c Ramdisk verification complete, start loading 1692 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk) 1693 13 common/cmd_bootm.c Start multifile image verification 1694 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue. 1695 15 common/cmd_bootm.c All preparation done, transferring control to OS 1696 1697 -30 lib_ppc/board.c Fatal error, hang the system 1698 -31 post/post.c POST test failed, detected by post_output_backlog() 1699 -32 post/post.c POST test failed, detected by post_run_single() 1700 1701 -1 common/cmd_doc.c Bad usage of "doc" command 1702 -1 common/cmd_doc.c No boot device 1703 -1 common/cmd_doc.c Unknown Chip ID on boot device 1704 -1 common/cmd_doc.c Read Error on boot device 1705 -1 common/cmd_doc.c Image header has bad magic number 1706 1707 -1 common/cmd_ide.c Bad usage of "ide" command 1708 -1 common/cmd_ide.c No boot device 1709 -1 common/cmd_ide.c Unknown boot device 1710 -1 common/cmd_ide.c Unknown partition table 1711 -1 common/cmd_ide.c Invalid partition type 1712 -1 common/cmd_ide.c Read Error on boot device 1713 -1 common/cmd_ide.c Image header has bad magic number 1714 1715 -1 common/cmd_nand.c Bad usage of "nand" command 1716 -1 common/cmd_nand.c No boot device 1717 -1 common/cmd_nand.c Unknown Chip ID on boot device 1718 -1 common/cmd_nand.c Read Error on boot device 1719 -1 common/cmd_nand.c Image header has bad magic number 1720 1721 -1 common/env_common.c Environment has a bad CRC, using default 1722 1723 1724Modem Support: 1725-------------- 1726 1727[so far only for SMDK2400 and TRAB boards] 1728 1729- Modem support endable: 1730 CONFIG_MODEM_SUPPORT 1731 1732- RTS/CTS Flow control enable: 1733 CONFIG_HWFLOW 1734 1735- Modem debug support: 1736 CONFIG_MODEM_SUPPORT_DEBUG 1737 1738 Enables debugging stuff (char screen[1024], dbg()) 1739 for modem support. Useful only with BDI2000. 1740 1741- Interrupt support (PPC): 1742 1743 There are common interrupt_init() and timer_interrupt() 1744 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1745 for cpu specific initialization. interrupt_init_cpu() 1746 should set decrementer_count to appropriate value. If 1747 cpu resets decrementer automatically after interrupt 1748 (ppc4xx) it should set decrementer_count to zero. 1749 timer_interrupt() calls timer_interrupt_cpu() for cpu 1750 specific handling. If board has watchdog / status_led 1751 / other_activity_monitor it works automatically from 1752 general timer_interrupt(). 1753 1754- General: 1755 1756 In the target system modem support is enabled when a 1757 specific key (key combination) is pressed during 1758 power-on. Otherwise U-Boot will boot normally 1759 (autoboot). The key_pressed() fuction is called from 1760 board_init(). Currently key_pressed() is a dummy 1761 function, returning 1 and thus enabling modem 1762 initialization. 1763 1764 If there are no modem init strings in the 1765 environment, U-Boot proceed to autoboot; the 1766 previous output (banner, info printfs) will be 1767 supressed, though. 1768 1769 See also: doc/README.Modem 1770 1771 1772Configuration Settings: 1773----------------------- 1774 1775- CFG_LONGHELP: Defined when you want long help messages included; 1776 undefine this when you're short of memory. 1777 1778- CFG_PROMPT: This is what U-Boot prints on the console to 1779 prompt for user input. 1780 1781- CFG_CBSIZE: Buffer size for input from the Console 1782 1783- CFG_PBSIZE: Buffer size for Console output 1784 1785- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1786 1787- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1788 the application (usually a Linux kernel) when it is 1789 booted 1790 1791- CFG_BAUDRATE_TABLE: 1792 List of legal baudrate settings for this board. 1793 1794- CFG_CONSOLE_INFO_QUIET 1795 Suppress display of console information at boot. 1796 1797- CFG_CONSOLE_IS_IN_ENV 1798 If the board specific function 1799 extern int overwrite_console (void); 1800 returns 1, the stdin, stderr and stdout are switched to the 1801 serial port, else the settings in the environment are used. 1802 1803- CFG_CONSOLE_OVERWRITE_ROUTINE 1804 Enable the call to overwrite_console(). 1805 1806- CFG_CONSOLE_ENV_OVERWRITE 1807 Enable overwrite of previous console environment settings. 1808 1809- CFG_MEMTEST_START, CFG_MEMTEST_END: 1810 Begin and End addresses of the area used by the 1811 simple memory test. 1812 1813- CFG_ALT_MEMTEST: 1814 Enable an alternate, more extensive memory test. 1815 1816- CFG_MEMTEST_SCRATCH: 1817 Scratch address used by the alternate memory test 1818 You only need to set this if address zero isn't writeable 1819 1820- CFG_TFTP_LOADADDR: 1821 Default load address for network file downloads 1822 1823- CFG_LOADS_BAUD_CHANGE: 1824 Enable temporary baudrate change while serial download 1825 1826- CFG_SDRAM_BASE: 1827 Physical start address of SDRAM. _Must_ be 0 here. 1828 1829- CFG_MBIO_BASE: 1830 Physical start address of Motherboard I/O (if using a 1831 Cogent motherboard) 1832 1833- CFG_FLASH_BASE: 1834 Physical start address of Flash memory. 1835 1836- CFG_MONITOR_BASE: 1837 Physical start address of boot monitor code (set by 1838 make config files to be same as the text base address 1839 (TEXT_BASE) used when linking) - same as 1840 CFG_FLASH_BASE when booting from flash. 1841 1842- CFG_MONITOR_LEN: 1843 Size of memory reserved for monitor code, used to 1844 determine _at_compile_time_ (!) if the environment is 1845 embedded within the U-Boot image, or in a separate 1846 flash sector. 1847 1848- CFG_MALLOC_LEN: 1849 Size of DRAM reserved for malloc() use. 1850 1851- CFG_BOOTM_LEN: 1852 Normally compressed uImages are limited to an 1853 uncompressed size of 8 MBytes. If this is not enough, 1854 you can define CFG_BOOTM_LEN in your board config file 1855 to adjust this setting to your needs. 1856 1857- CFG_BOOTMAPSZ: 1858 Maximum size of memory mapped by the startup code of 1859 the Linux kernel; all data that must be processed by 1860 the Linux kernel (bd_info, boot arguments, eventually 1861 initrd image) must be put below this limit. 1862 1863- CFG_MAX_FLASH_BANKS: 1864 Max number of Flash memory banks 1865 1866- CFG_MAX_FLASH_SECT: 1867 Max number of sectors on a Flash chip 1868 1869- CFG_FLASH_ERASE_TOUT: 1870 Timeout for Flash erase operations (in ms) 1871 1872- CFG_FLASH_WRITE_TOUT: 1873 Timeout for Flash write operations (in ms) 1874 1875- CFG_FLASH_LOCK_TOUT 1876 Timeout for Flash set sector lock bit operation (in ms) 1877 1878- CFG_FLASH_UNLOCK_TOUT 1879 Timeout for Flash clear lock bits operation (in ms) 1880 1881- CFG_FLASH_PROTECTION 1882 If defined, hardware flash sectors protection is used 1883 instead of U-Boot software protection. 1884 1885- CFG_DIRECT_FLASH_TFTP: 1886 1887 Enable TFTP transfers directly to flash memory; 1888 without this option such a download has to be 1889 performed in two steps: (1) download to RAM, and (2) 1890 copy from RAM to flash. 1891 1892 The two-step approach is usually more reliable, since 1893 you can check if the download worked before you erase 1894 the flash, but in some situations (when sytem RAM is 1895 too limited to allow for a tempory copy of the 1896 downloaded image) this option may be very useful. 1897 1898- CFG_FLASH_CFI: 1899 Define if the flash driver uses extra elements in the 1900 common flash structure for storing flash geometry. 1901 1902- CFG_FLASH_CFI_DRIVER 1903 This option also enables the building of the cfi_flash driver 1904 in the drivers directory 1905 1906- CFG_FLASH_QUIET_TEST 1907 If this option is defined, the common CFI flash doesn't 1908 print it's warning upon not recognized FLASH banks. This 1909 is useful, if some of the configured banks are only 1910 optionally available. 1911 1912- CFG_RX_ETH_BUFFER: 1913 Defines the number of ethernet receive buffers. On some 1914 ethernet controllers it is recommended to set this value 1915 to 8 or even higher (EEPRO100 or 405 EMAC), since all 1916 buffers can be full shortly after enabling the interface 1917 on high ethernet traffic. 1918 Defaults to 4 if not defined. 1919 1920The following definitions that deal with the placement and management 1921of environment data (variable area); in general, we support the 1922following configurations: 1923 1924- CFG_ENV_IS_IN_FLASH: 1925 1926 Define this if the environment is in flash memory. 1927 1928 a) The environment occupies one whole flash sector, which is 1929 "embedded" in the text segment with the U-Boot code. This 1930 happens usually with "bottom boot sector" or "top boot 1931 sector" type flash chips, which have several smaller 1932 sectors at the start or the end. For instance, such a 1933 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 1934 such a case you would place the environment in one of the 1935 4 kB sectors - with U-Boot code before and after it. With 1936 "top boot sector" type flash chips, you would put the 1937 environment in one of the last sectors, leaving a gap 1938 between U-Boot and the environment. 1939 1940 - CFG_ENV_OFFSET: 1941 1942 Offset of environment data (variable area) to the 1943 beginning of flash memory; for instance, with bottom boot 1944 type flash chips the second sector can be used: the offset 1945 for this sector is given here. 1946 1947 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 1948 1949 - CFG_ENV_ADDR: 1950 1951 This is just another way to specify the start address of 1952 the flash sector containing the environment (instead of 1953 CFG_ENV_OFFSET). 1954 1955 - CFG_ENV_SECT_SIZE: 1956 1957 Size of the sector containing the environment. 1958 1959 1960 b) Sometimes flash chips have few, equal sized, BIG sectors. 1961 In such a case you don't want to spend a whole sector for 1962 the environment. 1963 1964 - CFG_ENV_SIZE: 1965 1966 If you use this in combination with CFG_ENV_IS_IN_FLASH 1967 and CFG_ENV_SECT_SIZE, you can specify to use only a part 1968 of this flash sector for the environment. This saves 1969 memory for the RAM copy of the environment. 1970 1971 It may also save flash memory if you decide to use this 1972 when your environment is "embedded" within U-Boot code, 1973 since then the remainder of the flash sector could be used 1974 for U-Boot code. It should be pointed out that this is 1975 STRONGLY DISCOURAGED from a robustness point of view: 1976 updating the environment in flash makes it always 1977 necessary to erase the WHOLE sector. If something goes 1978 wrong before the contents has been restored from a copy in 1979 RAM, your target system will be dead. 1980 1981 - CFG_ENV_ADDR_REDUND 1982 CFG_ENV_SIZE_REDUND 1983 1984 These settings describe a second storage area used to hold 1985 a redundand copy of the environment data, so that there is 1986 a valid backup copy in case there is a power failure during 1987 a "saveenv" operation. 1988 1989BE CAREFUL! Any changes to the flash layout, and some changes to the 1990source code will make it necessary to adapt <board>/u-boot.lds* 1991accordingly! 1992 1993 1994- CFG_ENV_IS_IN_NVRAM: 1995 1996 Define this if you have some non-volatile memory device 1997 (NVRAM, battery buffered SRAM) which you want to use for the 1998 environment. 1999 2000 - CFG_ENV_ADDR: 2001 - CFG_ENV_SIZE: 2002 2003 These two #defines are used to determin the memory area you 2004 want to use for environment. It is assumed that this memory 2005 can just be read and written to, without any special 2006 provision. 2007 2008BE CAREFUL! The first access to the environment happens quite early 2009in U-Boot initalization (when we try to get the setting of for the 2010console baudrate). You *MUST* have mappend your NVRAM area then, or 2011U-Boot will hang. 2012 2013Please note that even with NVRAM we still use a copy of the 2014environment in RAM: we could work on NVRAM directly, but we want to 2015keep settings there always unmodified except somebody uses "saveenv" 2016to save the current settings. 2017 2018 2019- CFG_ENV_IS_IN_EEPROM: 2020 2021 Use this if you have an EEPROM or similar serial access 2022 device and a driver for it. 2023 2024 - CFG_ENV_OFFSET: 2025 - CFG_ENV_SIZE: 2026 2027 These two #defines specify the offset and size of the 2028 environment area within the total memory of your EEPROM. 2029 2030 - CFG_I2C_EEPROM_ADDR: 2031 If defined, specified the chip address of the EEPROM device. 2032 The default address is zero. 2033 2034 - CFG_EEPROM_PAGE_WRITE_BITS: 2035 If defined, the number of bits used to address bytes in a 2036 single page in the EEPROM device. A 64 byte page, for example 2037 would require six bits. 2038 2039 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 2040 If defined, the number of milliseconds to delay between 2041 page writes. The default is zero milliseconds. 2042 2043 - CFG_I2C_EEPROM_ADDR_LEN: 2044 The length in bytes of the EEPROM memory array address. Note 2045 that this is NOT the chip address length! 2046 2047 - CFG_I2C_EEPROM_ADDR_OVERFLOW: 2048 EEPROM chips that implement "address overflow" are ones 2049 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2050 address and the extra bits end up in the "chip address" bit 2051 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2052 byte chips. 2053 2054 Note that we consider the length of the address field to 2055 still be one byte because the extra address bits are hidden 2056 in the chip address. 2057 2058 - CFG_EEPROM_SIZE: 2059 The size in bytes of the EEPROM device. 2060 2061 2062- CFG_ENV_IS_IN_DATAFLASH: 2063 2064 Define this if you have a DataFlash memory device which you 2065 want to use for the environment. 2066 2067 - CFG_ENV_OFFSET: 2068 - CFG_ENV_ADDR: 2069 - CFG_ENV_SIZE: 2070 2071 These three #defines specify the offset and size of the 2072 environment area within the total memory of your DataFlash placed 2073 at the specified address. 2074 2075- CFG_ENV_IS_IN_NAND: 2076 2077 Define this if you have a NAND device which you want to use 2078 for the environment. 2079 2080 - CFG_ENV_OFFSET: 2081 - CFG_ENV_SIZE: 2082 2083 These two #defines specify the offset and size of the environment 2084 area within the first NAND device. 2085 2086 - CFG_ENV_OFFSET_REDUND 2087 2088 This setting describes a second storage area of CFG_ENV_SIZE 2089 size used to hold a redundant copy of the environment data, 2090 so that there is a valid backup copy in case there is a 2091 power failure during a "saveenv" operation. 2092 2093 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned 2094 to a block boundary, and CFG_ENV_SIZE must be a multiple of 2095 the NAND devices block size. 2096 2097- CFG_SPI_INIT_OFFSET 2098 2099 Defines offset to the initial SPI buffer area in DPRAM. The 2100 area is used at an early stage (ROM part) if the environment 2101 is configured to reside in the SPI EEPROM: We need a 520 byte 2102 scratch DPRAM area. It is used between the two initialization 2103 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2104 to be a good choice since it makes it far enough from the 2105 start of the data area as well as from the stack pointer. 2106 2107Please note that the environment is read-only as long as the monitor 2108has been relocated to RAM and a RAM copy of the environment has been 2109created; also, when using EEPROM you will have to use getenv_r() 2110until then to read environment variables. 2111 2112The environment is protected by a CRC32 checksum. Before the monitor 2113is relocated into RAM, as a result of a bad CRC you will be working 2114with the compiled-in default environment - *silently*!!! [This is 2115necessary, because the first environment variable we need is the 2116"baudrate" setting for the console - if we have a bad CRC, we don't 2117have any device yet where we could complain.] 2118 2119Note: once the monitor has been relocated, then it will complain if 2120the default environment is used; a new CRC is computed as soon as you 2121use the "saveenv" command to store a valid environment. 2122 2123- CFG_FAULT_ECHO_LINK_DOWN: 2124 Echo the inverted Ethernet link state to the fault LED. 2125 2126 Note: If this option is active, then CFG_FAULT_MII_ADDR 2127 also needs to be defined. 2128 2129- CFG_FAULT_MII_ADDR: 2130 MII address of the PHY to check for the Ethernet link state. 2131 2132- CFG_64BIT_VSPRINTF: 2133 Makes vsprintf (and all *printf functions) support printing 2134 of 64bit values by using the L quantifier 2135 2136- CFG_64BIT_STRTOUL: 2137 Adds simple_strtoull that returns a 64bit value 2138 2139Low Level (hardware related) configuration options: 2140--------------------------------------------------- 2141 2142- CFG_CACHELINE_SIZE: 2143 Cache Line Size of the CPU. 2144 2145- CFG_DEFAULT_IMMR: 2146 Default address of the IMMR after system reset. 2147 2148 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2149 and RPXsuper) to be able to adjust the position of 2150 the IMMR register after a reset. 2151 2152- Floppy Disk Support: 2153 CFG_FDC_DRIVE_NUMBER 2154 2155 the default drive number (default value 0) 2156 2157 CFG_ISA_IO_STRIDE 2158 2159 defines the spacing between fdc chipset registers 2160 (default value 1) 2161 2162 CFG_ISA_IO_OFFSET 2163 2164 defines the offset of register from address. It 2165 depends on which part of the data bus is connected to 2166 the fdc chipset. (default value 0) 2167 2168 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 2169 CFG_FDC_DRIVE_NUMBER are undefined, they take their 2170 default value. 2171 2172 if CFG_FDC_HW_INIT is defined, then the function 2173 fdc_hw_init() is called at the beginning of the FDC 2174 setup. fdc_hw_init() must be provided by the board 2175 source code. It is used to make hardware dependant 2176 initializations. 2177 2178- CFG_IMMR: Physical address of the Internal Memory. 2179 DO NOT CHANGE unless you know exactly what you're 2180 doing! (11-4) [MPC8xx/82xx systems only] 2181 2182- CFG_INIT_RAM_ADDR: 2183 2184 Start address of memory area that can be used for 2185 initial data and stack; please note that this must be 2186 writable memory that is working WITHOUT special 2187 initialization, i. e. you CANNOT use normal RAM which 2188 will become available only after programming the 2189 memory controller and running certain initialization 2190 sequences. 2191 2192 U-Boot uses the following memory types: 2193 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2194 - MPC824X: data cache 2195 - PPC4xx: data cache 2196 2197- CFG_GBL_DATA_OFFSET: 2198 2199 Offset of the initial data structure in the memory 2200 area defined by CFG_INIT_RAM_ADDR. Usually 2201 CFG_GBL_DATA_OFFSET is chosen such that the initial 2202 data is located at the end of the available space 2203 (sometimes written as (CFG_INIT_RAM_END - 2204 CFG_INIT_DATA_SIZE), and the initial stack is just 2205 below that area (growing from (CFG_INIT_RAM_ADDR + 2206 CFG_GBL_DATA_OFFSET) downward. 2207 2208 Note: 2209 On the MPC824X (or other systems that use the data 2210 cache for initial memory) the address chosen for 2211 CFG_INIT_RAM_ADDR is basically arbitrary - it must 2212 point to an otherwise UNUSED address space between 2213 the top of RAM and the start of the PCI space. 2214 2215- CFG_SIUMCR: SIU Module Configuration (11-6) 2216 2217- CFG_SYPCR: System Protection Control (11-9) 2218 2219- CFG_TBSCR: Time Base Status and Control (11-26) 2220 2221- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 2222 2223- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2224 2225- CFG_SCCR: System Clock and reset Control Register (15-27) 2226 2227- CFG_OR_TIMING_SDRAM: 2228 SDRAM timing 2229 2230- CFG_MAMR_PTA: 2231 periodic timer for refresh 2232 2233- CFG_DER: Debug Event Register (37-47) 2234 2235- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 2236 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 2237 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 2238 CFG_BR1_PRELIM: 2239 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2240 2241- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2242 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 2243 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 2244 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2245 2246- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 2247 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 2248 Machine Mode Register and Memory Periodic Timer 2249 Prescaler definitions (SDRAM timing) 2250 2251- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 2252 enable I2C microcode relocation patch (MPC8xx); 2253 define relocation offset in DPRAM [DSP2] 2254 2255- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 2256 enable SPI microcode relocation patch (MPC8xx); 2257 define relocation offset in DPRAM [SCC4] 2258 2259- CFG_USE_OSCCLK: 2260 Use OSCM clock mode on MBX8xx board. Be careful, 2261 wrong setting might damage your board. Read 2262 doc/README.MBX before setting this variable! 2263 2264- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2265 Offset of the bootmode word in DPRAM used by post 2266 (Power On Self Tests). This definition overrides 2267 #define'd default value in commproc.h resp. 2268 cpm_8260.h. 2269 2270- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 2271 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 2272 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 2273 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 2274 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2275 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 2276 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 2277 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 2278 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 2279 2280- CONFIG_SPD_EEPROM 2281 Get DDR timing information from an I2C EEPROM. Common with pluggable 2282 memory modules such as SODIMMs 2283 SPD_EEPROM_ADDRESS 2284 I2C address of the SPD EEPROM 2285 2286- CFG_SPD_BUS_NUM 2287 If SPD EEPROM is on an I2C bus other than the first one, specify here. 2288 Note that the value must resolve to something your driver can deal with. 2289 2290- CFG_83XX_DDR_USES_CS0 2291 Only for 83xx systems. If specified, then DDR should be configured 2292 using CS0 and CS1 instead of CS2 and CS3. 2293 2294- CFG_83XX_DDR_USES_CS0 2295 Only for 83xx systems. If specified, then DDR should be configured 2296 using CS0 and CS1 instead of CS2 and CS3. 2297 2298- CONFIG_ETHER_ON_FEC[12] 2299 Define to enable FEC[12] on a 8xx series processor. 2300 2301- CONFIG_FEC[12]_PHY 2302 Define to the hardcoded PHY address which corresponds 2303 to the given FEC; i. e. 2304 #define CONFIG_FEC1_PHY 4 2305 means that the PHY with address 4 is connected to FEC1 2306 2307 When set to -1, means to probe for first available. 2308 2309- CONFIG_FEC[12]_PHY_NORXERR 2310 The PHY does not have a RXERR line (RMII only). 2311 (so program the FEC to ignore it). 2312 2313- CONFIG_RMII 2314 Enable RMII mode for all FECs. 2315 Note that this is a global option, we can't 2316 have one FEC in standard MII mode and another in RMII mode. 2317 2318- CONFIG_CRC32_VERIFY 2319 Add a verify option to the crc32 command. 2320 The syntax is: 2321 2322 => crc32 -v <address> <count> <crc32> 2323 2324 Where address/count indicate a memory area 2325 and crc32 is the correct crc32 which the 2326 area should have. 2327 2328- CONFIG_LOOPW 2329 Add the "loopw" memory command. This only takes effect if 2330 the memory commands are activated globally (CFG_CMD_MEM). 2331 2332- CONFIG_MX_CYCLIC 2333 Add the "mdc" and "mwc" memory commands. These are cyclic 2334 "md/mw" commands. 2335 Examples: 2336 2337 => mdc.b 10 4 500 2338 This command will print 4 bytes (10,11,12,13) each 500 ms. 2339 2340 => mwc.l 100 12345678 10 2341 This command will write 12345678 to address 100 all 10 ms. 2342 2343 This only takes effect if the memory commands are activated 2344 globally (CFG_CMD_MEM). 2345 2346- CONFIG_SKIP_LOWLEVEL_INIT 2347- CONFIG_SKIP_RELOCATE_UBOOT 2348 2349 [ARM only] If these variables are defined, then 2350 certain low level initializations (like setting up 2351 the memory controller) are omitted and/or U-Boot does 2352 not relocate itself into RAM. 2353 Normally these variables MUST NOT be defined. The 2354 only exception is when U-Boot is loaded (to RAM) by 2355 some other boot loader or by a debugger which 2356 performs these intializations itself. 2357 2358 2359Building the Software: 2360====================== 2361 2362Building U-Boot has been tested in native PPC environments (on a 2363PowerBook G3 running LinuxPPC 2000) and in cross environments 2364(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and 2365NetBSD 1.5 on x86). 2366 2367If you are not using a native PPC environment, it is assumed that you 2368have the GNU cross compiling tools available in your path and named 2369with a prefix of "powerpc-linux-". If this is not the case, (e.g. if 2370you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change 2371the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU, 2372change it to: 2373 2374 CROSS_COMPILE = ppc_4xx- 2375 2376 2377U-Boot is intended to be simple to build. After installing the 2378sources you must configure U-Boot for one specific board type. This 2379is done by typing: 2380 2381 make NAME_config 2382 2383where "NAME_config" is the name of one of the existing 2384configurations; the following names are supported: 2385 2386 ADCIOP_config FPS860L_config omap730p2_config 2387 ADS860_config GEN860T_config pcu_e_config 2388 Alaska8220_config 2389 AR405_config GENIETV_config PIP405_config 2390 at91rm9200dk_config GTH_config QS823_config 2391 CANBT_config hermes_config QS850_config 2392 cmi_mpc5xx_config hymod_config QS860T_config 2393 cogent_common_config IP860_config RPXlite_config 2394 cogent_mpc8260_config IVML24_config RPXlite_DW_config 2395 cogent_mpc8xx_config IVMS8_config RPXsuper_config 2396 CPCI405_config JSE_config rsdproto_config 2397 CPCIISER4_config LANTEC_config Sandpoint8240_config 2398 csb272_config lwmon_config sbc8260_config 2399 CU824_config MBX860T_config sbc8560_33_config 2400 DUET_ADS_config MBX_config sbc8560_66_config 2401 EBONY_config mpc7448hpc2_config SM850_config 2402 ELPT860_config MPC8260ADS_config SPD823TS_config 2403 ESTEEM192E_config MPC8540ADS_config stxgp3_config 2404 ETX094_config MPC8540EVAL_config SXNI855T_config 2405 FADS823_config NMPC8560ADS_config TQM823L_config 2406 FADS850SAR_config NETVIA_config TQM850L_config 2407 FADS860T_config omap1510inn_config TQM855L_config 2408 FPS850L_config omap1610h2_config TQM860L_config 2409 omap1610inn_config walnut_config 2410 omap5912osk_config Yukon8220_config 2411 omap2420h4_config ZPC1900_config 2412 2413Note: for some board special configuration names may exist; check if 2414 additional information is available from the board vendor; for 2415 instance, the TQM823L systems are available without (standard) 2416 or with LCD support. You can select such additional "features" 2417 when chosing the configuration, i. e. 2418 2419 make TQM823L_config 2420 - will configure for a plain TQM823L, i. e. no LCD support 2421 2422 make TQM823L_LCD_config 2423 - will configure for a TQM823L with U-Boot console on LCD 2424 2425 etc. 2426 2427 2428Finally, type "make all", and you should get some working U-Boot 2429images ready for download to / installation on your system: 2430 2431- "u-boot.bin" is a raw binary image 2432- "u-boot" is an image in ELF binary format 2433- "u-boot.srec" is in Motorola S-Record format 2434 2435By default the build is performed locally and the objects are saved 2436in the source directory. One of the two methods can be used to change 2437this behavior and build U-Boot to some external directory: 2438 24391. Add O= to the make command line invocations: 2440 2441 make O=/tmp/build distclean 2442 make O=/tmp/build NAME_config 2443 make O=/tmp/build all 2444 24452. Set environment variable BUILD_DIR to point to the desired location: 2446 2447 export BUILD_DIR=/tmp/build 2448 make distclean 2449 make NAME_config 2450 make all 2451 2452Note that the command line "O=" setting overrides the BUILD_DIR environment 2453variable. 2454 2455 2456Please be aware that the Makefiles assume you are using GNU make, so 2457for instance on NetBSD you might need to use "gmake" instead of 2458native "make". 2459 2460 2461If the system board that you have is not listed, then you will need 2462to port U-Boot to your hardware platform. To do this, follow these 2463steps: 2464 24651. Add a new configuration option for your board to the toplevel 2466 "Makefile" and to the "MAKEALL" script, using the existing 2467 entries as examples. Note that here and at many other places 2468 boards and other names are listed in alphabetical sort order. Please 2469 keep this order. 24702. Create a new directory to hold your board specific code. Add any 2471 files you need. In your board directory, you will need at least 2472 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 24733. Create a new configuration file "include/configs/<board>.h" for 2474 your board 24753. If you're porting U-Boot to a new CPU, then also create a new 2476 directory to hold your CPU specific code. Add any files you need. 24774. Run "make <board>_config" with your new name. 24785. Type "make", and you should get a working "u-boot.srec" file 2479 to be installed on your target system. 24806. Debug and solve any problems that might arise. 2481 [Of course, this last step is much harder than it sounds.] 2482 2483 2484Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2485============================================================== 2486 2487If you have modified U-Boot sources (for instance added a new board 2488or support for new devices, a new CPU, etc.) you are expected to 2489provide feedback to the other developers. The feedback normally takes 2490the form of a "patch", i. e. a context diff against a certain (latest 2491official or latest in CVS) version of U-Boot sources. 2492 2493But before you submit such a patch, please verify that your modifi- 2494cation did not break existing code. At least make sure that *ALL* of 2495the supported boards compile WITHOUT ANY compiler warnings. To do so, 2496just run the "MAKEALL" script, which will configure and build U-Boot 2497for ALL supported system. Be warned, this will take a while. You can 2498select which (cross) compiler to use by passing a `CROSS_COMPILE' 2499environment variable to the script, i. e. to use the cross tools from 2500MontaVista's Hard Hat Linux you can type 2501 2502 CROSS_COMPILE=ppc_8xx- MAKEALL 2503 2504or to build on a native PowerPC system you can type 2505 2506 CROSS_COMPILE=' ' MAKEALL 2507 2508When using the MAKEALL script, the default behaviour is to build U-Boot 2509in the source directory. This location can be changed by setting the 2510BUILD_DIR environment variable. Also, for each target built, the MAKEALL 2511script saves two log files (<target>.ERR and <target>.MAKEALL) in the 2512<source dir>/LOG directory. This default location can be changed by 2513setting the MAKEALL_LOGDIR environment variable. For example: 2514 2515 export BUILD_DIR=/tmp/build 2516 export MAKEALL_LOGDIR=/tmp/log 2517 CROSS_COMPILE=ppc_8xx- MAKEALL 2518 2519With the above settings build objects are saved in the /tmp/build, log 2520files are saved in the /tmp/log and the source tree remains clean during 2521the whole build process. 2522 2523 2524See also "U-Boot Porting Guide" below. 2525 2526 2527Monitor Commands - Overview: 2528============================ 2529 2530go - start application at address 'addr' 2531run - run commands in an environment variable 2532bootm - boot application image from memory 2533bootp - boot image via network using BootP/TFTP protocol 2534tftpboot- boot image via network using TFTP protocol 2535 and env variables "ipaddr" and "serverip" 2536 (and eventually "gatewayip") 2537rarpboot- boot image via network using RARP/TFTP protocol 2538diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2539loads - load S-Record file over serial line 2540loadb - load binary file over serial line (kermit mode) 2541md - memory display 2542mm - memory modify (auto-incrementing) 2543nm - memory modify (constant address) 2544mw - memory write (fill) 2545cp - memory copy 2546cmp - memory compare 2547crc32 - checksum calculation 2548imd - i2c memory display 2549imm - i2c memory modify (auto-incrementing) 2550inm - i2c memory modify (constant address) 2551imw - i2c memory write (fill) 2552icrc32 - i2c checksum calculation 2553iprobe - probe to discover valid I2C chip addresses 2554iloop - infinite loop on address range 2555isdram - print SDRAM configuration information 2556sspi - SPI utility commands 2557base - print or set address offset 2558printenv- print environment variables 2559setenv - set environment variables 2560saveenv - save environment variables to persistent storage 2561protect - enable or disable FLASH write protection 2562erase - erase FLASH memory 2563flinfo - print FLASH memory information 2564bdinfo - print Board Info structure 2565iminfo - print header information for application image 2566coninfo - print console devices and informations 2567ide - IDE sub-system 2568loop - infinite loop on address range 2569loopw - infinite write loop on address range 2570mtest - simple RAM test 2571icache - enable or disable instruction cache 2572dcache - enable or disable data cache 2573reset - Perform RESET of the CPU 2574echo - echo args to console 2575version - print monitor version 2576help - print online help 2577? - alias for 'help' 2578 2579 2580Monitor Commands - Detailed Description: 2581======================================== 2582 2583TODO. 2584 2585For now: just type "help <command>". 2586 2587 2588Environment Variables: 2589====================== 2590 2591U-Boot supports user configuration using Environment Variables which 2592can be made persistent by saving to Flash memory. 2593 2594Environment Variables are set using "setenv", printed using 2595"printenv", and saved to Flash using "saveenv". Using "setenv" 2596without a value can be used to delete a variable from the 2597environment. As long as you don't save the environment you are 2598working with an in-memory copy. In case the Flash area containing the 2599environment is erased by accident, a default environment is provided. 2600 2601Some configuration options can be set using Environment Variables: 2602 2603 baudrate - see CONFIG_BAUDRATE 2604 2605 bootdelay - see CONFIG_BOOTDELAY 2606 2607 bootcmd - see CONFIG_BOOTCOMMAND 2608 2609 bootargs - Boot arguments when booting an RTOS image 2610 2611 bootfile - Name of the image to load with TFTP 2612 2613 autoload - if set to "no" (any string beginning with 'n'), 2614 "bootp" will just load perform a lookup of the 2615 configuration from the BOOTP server, but not try to 2616 load any image using TFTP 2617 2618 autostart - if set to "yes", an image loaded using the "bootp", 2619 "rarpboot", "tftpboot" or "diskboot" commands will 2620 be automatically started (by internally calling 2621 "bootm") 2622 2623 If set to "no", a standalone image passed to the 2624 "bootm" command will be copied to the load address 2625 (and eventually uncompressed), but NOT be started. 2626 This can be used to load and uncompress arbitrary 2627 data. 2628 2629 i2cfast - (PPC405GP|PPC405EP only) 2630 if set to 'y' configures Linux I2C driver for fast 2631 mode (400kHZ). This environment variable is used in 2632 initialization code. So, for changes to be effective 2633 it must be saved and board must be reset. 2634 2635 initrd_high - restrict positioning of initrd images: 2636 If this variable is not set, initrd images will be 2637 copied to the highest possible address in RAM; this 2638 is usually what you want since it allows for 2639 maximum initrd size. If for some reason you want to 2640 make sure that the initrd image is loaded below the 2641 CFG_BOOTMAPSZ limit, you can set this environment 2642 variable to a value of "no" or "off" or "0". 2643 Alternatively, you can set it to a maximum upper 2644 address to use (U-Boot will still check that it 2645 does not overwrite the U-Boot stack and data). 2646 2647 For instance, when you have a system with 16 MB 2648 RAM, and want to reserve 4 MB from use by Linux, 2649 you can do this by adding "mem=12M" to the value of 2650 the "bootargs" variable. However, now you must make 2651 sure that the initrd image is placed in the first 2652 12 MB as well - this can be done with 2653 2654 setenv initrd_high 00c00000 2655 2656 If you set initrd_high to 0xFFFFFFFF, this is an 2657 indication to U-Boot that all addresses are legal 2658 for the Linux kernel, including addresses in flash 2659 memory. In this case U-Boot will NOT COPY the 2660 ramdisk at all. This may be useful to reduce the 2661 boot time on your system, but requires that this 2662 feature is supported by your Linux kernel. 2663 2664 ipaddr - IP address; needed for tftpboot command 2665 2666 loadaddr - Default load address for commands like "bootp", 2667 "rarpboot", "tftpboot", "loadb" or "diskboot" 2668 2669 loads_echo - see CONFIG_LOADS_ECHO 2670 2671 serverip - TFTP server IP address; needed for tftpboot command 2672 2673 bootretry - see CONFIG_BOOT_RETRY_TIME 2674 2675 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2676 2677 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2678 2679 ethprime - When CONFIG_NET_MULTI is enabled controls which 2680 interface is used first. 2681 2682 ethact - When CONFIG_NET_MULTI is enabled controls which 2683 interface is currently active. For example you 2684 can do the following 2685 2686 => setenv ethact FEC ETHERNET 2687 => ping 192.168.0.1 # traffic sent on FEC ETHERNET 2688 => setenv ethact SCC ETHERNET 2689 => ping 10.0.0.1 # traffic sent on SCC ETHERNET 2690 2691 netretry - When set to "no" each network operation will 2692 either succeed or fail without retrying. 2693 When set to "once" the network operation will 2694 fail when all the available network interfaces 2695 are tried once without success. 2696 Useful on scripts which control the retry operation 2697 themselves. 2698 2699 tftpsrcport - If this is set, the value is used for TFTP's 2700 UDP source port. 2701 2702 tftpdstport - If this is set, the value is used for TFTP's UDP 2703 destination port instead of the Well Know Port 69. 2704 2705 vlan - When set to a value < 4095 the traffic over 2706 ethernet is encapsulated/received over 802.1q 2707 VLAN tagged frames. 2708 2709The following environment variables may be used and automatically 2710updated by the network boot commands ("bootp" and "rarpboot"), 2711depending the information provided by your boot server: 2712 2713 bootfile - see above 2714 dnsip - IP address of your Domain Name Server 2715 dnsip2 - IP address of your secondary Domain Name Server 2716 gatewayip - IP address of the Gateway (Router) to use 2717 hostname - Target hostname 2718 ipaddr - see above 2719 netmask - Subnet Mask 2720 rootpath - Pathname of the root filesystem on the NFS server 2721 serverip - see above 2722 2723 2724There are two special Environment Variables: 2725 2726 serial# - contains hardware identification information such 2727 as type string and/or serial number 2728 ethaddr - Ethernet address 2729 2730These variables can be set only once (usually during manufacturing of 2731the board). U-Boot refuses to delete or overwrite these variables 2732once they have been set once. 2733 2734 2735Further special Environment Variables: 2736 2737 ver - Contains the U-Boot version string as printed 2738 with the "version" command. This variable is 2739 readonly (see CONFIG_VERSION_VARIABLE). 2740 2741 2742Please note that changes to some configuration parameters may take 2743only effect after the next boot (yes, that's just like Windoze :-). 2744 2745 2746Command Line Parsing: 2747===================== 2748 2749There are two different command line parsers available with U-Boot: 2750the old "simple" one, and the much more powerful "hush" shell: 2751 2752Old, simple command line parser: 2753-------------------------------- 2754 2755- supports environment variables (through setenv / saveenv commands) 2756- several commands on one line, separated by ';' 2757- variable substitution using "... ${name} ..." syntax 2758- special characters ('$', ';') can be escaped by prefixing with '\', 2759 for example: 2760 setenv bootcmd bootm \${address} 2761- You can also escape text by enclosing in single apostrophes, for example: 2762 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2763 2764Hush shell: 2765----------- 2766 2767- similar to Bourne shell, with control structures like 2768 if...then...else...fi, for...do...done; while...do...done, 2769 until...do...done, ... 2770- supports environment ("global") variables (through setenv / saveenv 2771 commands) and local shell variables (through standard shell syntax 2772 "name=value"); only environment variables can be used with "run" 2773 command 2774 2775General rules: 2776-------------- 2777 2778(1) If a command line (or an environment variable executed by a "run" 2779 command) contains several commands separated by semicolon, and 2780 one of these commands fails, then the remaining commands will be 2781 executed anyway. 2782 2783(2) If you execute several variables with one call to run (i. e. 2784 calling run with a list af variables as arguments), any failing 2785 command will cause "run" to terminate, i. e. the remaining 2786 variables are not executed. 2787 2788Note for Redundant Ethernet Interfaces: 2789======================================= 2790 2791Some boards come with redundant ethernet interfaces; U-Boot supports 2792such configurations and is capable of automatic selection of a 2793"working" interface when needed. MAC assignment works as follows: 2794 2795Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2796MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2797"eth1addr" (=>eth1), "eth2addr", ... 2798 2799If the network interface stores some valid MAC address (for instance 2800in SROM), this is used as default address if there is NO correspon- 2801ding setting in the environment; if the corresponding environment 2802variable is set, this overrides the settings in the card; that means: 2803 2804o If the SROM has a valid MAC address, and there is no address in the 2805 environment, the SROM's address is used. 2806 2807o If there is no valid address in the SROM, and a definition in the 2808 environment exists, then the value from the environment variable is 2809 used. 2810 2811o If both the SROM and the environment contain a MAC address, and 2812 both addresses are the same, this MAC address is used. 2813 2814o If both the SROM and the environment contain a MAC address, and the 2815 addresses differ, the value from the environment is used and a 2816 warning is printed. 2817 2818o If neither SROM nor the environment contain a MAC address, an error 2819 is raised. 2820 2821 2822Image Formats: 2823============== 2824 2825The "boot" commands of this monitor operate on "image" files which 2826can be basicly anything, preceeded by a special header; see the 2827definitions in include/image.h for details; basicly, the header 2828defines the following image properties: 2829 2830* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2831 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2832 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2833 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 2834* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 2835 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 2836 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC). 2837* Compression Type (uncompressed, gzip, bzip2) 2838* Load Address 2839* Entry Point 2840* Image Name 2841* Image Timestamp 2842 2843The header is marked by a special Magic Number, and both the header 2844and the data portions of the image are secured against corruption by 2845CRC32 checksums. 2846 2847 2848Linux Support: 2849============== 2850 2851Although U-Boot should support any OS or standalone application 2852easily, the main focus has always been on Linux during the design of 2853U-Boot. 2854 2855U-Boot includes many features that so far have been part of some 2856special "boot loader" code within the Linux kernel. Also, any 2857"initrd" images to be used are no longer part of one big Linux image; 2858instead, kernel and "initrd" are separate images. This implementation 2859serves several purposes: 2860 2861- the same features can be used for other OS or standalone 2862 applications (for instance: using compressed images to reduce the 2863 Flash memory footprint) 2864 2865- it becomes much easier to port new Linux kernel versions because 2866 lots of low-level, hardware dependent stuff are done by U-Boot 2867 2868- the same Linux kernel image can now be used with different "initrd" 2869 images; of course this also means that different kernel images can 2870 be run with the same "initrd". This makes testing easier (you don't 2871 have to build a new "zImage.initrd" Linux image when you just 2872 change a file in your "initrd"). Also, a field-upgrade of the 2873 software is easier now. 2874 2875 2876Linux HOWTO: 2877============ 2878 2879Porting Linux to U-Boot based systems: 2880--------------------------------------- 2881 2882U-Boot cannot save you from doing all the necessary modifications to 2883configure the Linux device drivers for use with your target hardware 2884(no, we don't intend to provide a full virtual machine interface to 2885Linux :-). 2886 2887But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 2888 2889Just make sure your machine specific header file (for instance 2890include/asm-ppc/tqm8xx.h) includes the same definition of the Board 2891Information structure as we define in include/u-boot.h, and make 2892sure that your definition of IMAP_ADDR uses the same value as your 2893U-Boot configuration in CFG_IMMR. 2894 2895 2896Configuring the Linux kernel: 2897----------------------------- 2898 2899No specific requirements for U-Boot. Make sure you have some root 2900device (initial ramdisk, NFS) for your target system. 2901 2902 2903Building a Linux Image: 2904----------------------- 2905 2906With U-Boot, "normal" build targets like "zImage" or "bzImage" are 2907not used. If you use recent kernel source, a new build target 2908"uImage" will exist which automatically builds an image usable by 2909U-Boot. Most older kernels also have support for a "pImage" target, 2910which was introduced for our predecessor project PPCBoot and uses a 2911100% compatible format. 2912 2913Example: 2914 2915 make TQM850L_config 2916 make oldconfig 2917 make dep 2918 make uImage 2919 2920The "uImage" build target uses a special tool (in 'tools/mkimage') to 2921encapsulate a compressed Linux kernel image with header information, 2922CRC32 checksum etc. for use with U-Boot. This is what we are doing: 2923 2924* build a standard "vmlinux" kernel image (in ELF binary format): 2925 2926* convert the kernel into a raw binary image: 2927 2928 ${CROSS_COMPILE}-objcopy -O binary \ 2929 -R .note -R .comment \ 2930 -S vmlinux linux.bin 2931 2932* compress the binary image: 2933 2934 gzip -9 linux.bin 2935 2936* package compressed binary image for U-Boot: 2937 2938 mkimage -A ppc -O linux -T kernel -C gzip \ 2939 -a 0 -e 0 -n "Linux Kernel Image" \ 2940 -d linux.bin.gz uImage 2941 2942 2943The "mkimage" tool can also be used to create ramdisk images for use 2944with U-Boot, either separated from the Linux kernel image, or 2945combined into one file. "mkimage" encapsulates the images with a 64 2946byte header containing information about target architecture, 2947operating system, image type, compression method, entry points, time 2948stamp, CRC32 checksums, etc. 2949 2950"mkimage" can be called in two ways: to verify existing images and 2951print the header information, or to build new images. 2952 2953In the first form (with "-l" option) mkimage lists the information 2954contained in the header of an existing U-Boot image; this includes 2955checksum verification: 2956 2957 tools/mkimage -l image 2958 -l ==> list image header information 2959 2960The second form (with "-d" option) is used to build a U-Boot image 2961from a "data file" which is used as image payload: 2962 2963 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 2964 -n name -d data_file image 2965 -A ==> set architecture to 'arch' 2966 -O ==> set operating system to 'os' 2967 -T ==> set image type to 'type' 2968 -C ==> set compression type 'comp' 2969 -a ==> set load address to 'addr' (hex) 2970 -e ==> set entry point to 'ep' (hex) 2971 -n ==> set image name to 'name' 2972 -d ==> use image data from 'datafile' 2973 2974Right now, all Linux kernels for PowerPC systems use the same load 2975address (0x00000000), but the entry point address depends on the 2976kernel version: 2977 2978- 2.2.x kernels have the entry point at 0x0000000C, 2979- 2.3.x and later kernels have the entry point at 0x00000000. 2980 2981So a typical call to build a U-Boot image would read: 2982 2983 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2984 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 2985 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 2986 > examples/uImage.TQM850L 2987 Image Name: 2.4.4 kernel for TQM850L 2988 Created: Wed Jul 19 02:34:59 2000 2989 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2990 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2991 Load Address: 0x00000000 2992 Entry Point: 0x00000000 2993 2994To verify the contents of the image (or check for corruption): 2995 2996 -> tools/mkimage -l examples/uImage.TQM850L 2997 Image Name: 2.4.4 kernel for TQM850L 2998 Created: Wed Jul 19 02:34:59 2000 2999 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3000 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3001 Load Address: 0x00000000 3002 Entry Point: 0x00000000 3003 3004NOTE: for embedded systems where boot time is critical you can trade 3005speed for memory and install an UNCOMPRESSED image instead: this 3006needs more space in Flash, but boots much faster since it does not 3007need to be uncompressed: 3008 3009 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 3010 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3011 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3012 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 3013 > examples/uImage.TQM850L-uncompressed 3014 Image Name: 2.4.4 kernel for TQM850L 3015 Created: Wed Jul 19 02:34:59 2000 3016 Image Type: PowerPC Linux Kernel Image (uncompressed) 3017 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3018 Load Address: 0x00000000 3019 Entry Point: 0x00000000 3020 3021 3022Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3023when your kernel is intended to use an initial ramdisk: 3024 3025 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3026 > -A ppc -O linux -T ramdisk -C gzip \ 3027 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3028 Image Name: Simple Ramdisk Image 3029 Created: Wed Jan 12 14:01:50 2000 3030 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3031 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3032 Load Address: 0x00000000 3033 Entry Point: 0x00000000 3034 3035 3036Installing a Linux Image: 3037------------------------- 3038 3039To downloading a U-Boot image over the serial (console) interface, 3040you must convert the image to S-Record format: 3041 3042 objcopy -I binary -O srec examples/image examples/image.srec 3043 3044The 'objcopy' does not understand the information in the U-Boot 3045image header, so the resulting S-Record file will be relative to 3046address 0x00000000. To load it to a given address, you need to 3047specify the target address as 'offset' parameter with the 'loads' 3048command. 3049 3050Example: install the image to address 0x40100000 (which on the 3051TQM8xxL is in the first Flash bank): 3052 3053 => erase 40100000 401FFFFF 3054 3055 .......... done 3056 Erased 8 sectors 3057 3058 => loads 40100000 3059 ## Ready for S-Record download ... 3060 ~>examples/image.srec 3061 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3062 ... 3063 15989 15990 15991 15992 3064 [file transfer complete] 3065 [connected] 3066 ## Start Addr = 0x00000000 3067 3068 3069You can check the success of the download using the 'iminfo' command; 3070this includes a checksum verification so you can be sure no data 3071corruption happened: 3072 3073 => imi 40100000 3074 3075 ## Checking Image at 40100000 ... 3076 Image Name: 2.2.13 for initrd on TQM850L 3077 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3078 Data Size: 335725 Bytes = 327 kB = 0 MB 3079 Load Address: 00000000 3080 Entry Point: 0000000c 3081 Verifying Checksum ... OK 3082 3083 3084Boot Linux: 3085----------- 3086 3087The "bootm" command is used to boot an application that is stored in 3088memory (RAM or Flash). In case of a Linux kernel image, the contents 3089of the "bootargs" environment variable is passed to the kernel as 3090parameters. You can check and modify this variable using the 3091"printenv" and "setenv" commands: 3092 3093 3094 => printenv bootargs 3095 bootargs=root=/dev/ram 3096 3097 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3098 3099 => printenv bootargs 3100 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3101 3102 => bootm 40020000 3103 ## Booting Linux kernel at 40020000 ... 3104 Image Name: 2.2.13 for NFS on TQM850L 3105 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3106 Data Size: 381681 Bytes = 372 kB = 0 MB 3107 Load Address: 00000000 3108 Entry Point: 0000000c 3109 Verifying Checksum ... OK 3110 Uncompressing Kernel Image ... OK 3111 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 3112 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3113 time_init: decrementer frequency = 187500000/60 3114 Calibrating delay loop... 49.77 BogoMIPS 3115 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3116 ... 3117 3118If you want to boot a Linux kernel with initial ram disk, you pass 3119the memory addresses of both the kernel and the initrd image (PPBCOOT 3120format!) to the "bootm" command: 3121 3122 => imi 40100000 40200000 3123 3124 ## Checking Image at 40100000 ... 3125 Image Name: 2.2.13 for initrd on TQM850L 3126 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3127 Data Size: 335725 Bytes = 327 kB = 0 MB 3128 Load Address: 00000000 3129 Entry Point: 0000000c 3130 Verifying Checksum ... OK 3131 3132 ## Checking Image at 40200000 ... 3133 Image Name: Simple Ramdisk Image 3134 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3135 Data Size: 566530 Bytes = 553 kB = 0 MB 3136 Load Address: 00000000 3137 Entry Point: 00000000 3138 Verifying Checksum ... OK 3139 3140 => bootm 40100000 40200000 3141 ## Booting Linux kernel at 40100000 ... 3142 Image Name: 2.2.13 for initrd on TQM850L 3143 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3144 Data Size: 335725 Bytes = 327 kB = 0 MB 3145 Load Address: 00000000 3146 Entry Point: 0000000c 3147 Verifying Checksum ... OK 3148 Uncompressing Kernel Image ... OK 3149 ## Loading RAMDisk Image at 40200000 ... 3150 Image Name: Simple Ramdisk Image 3151 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3152 Data Size: 566530 Bytes = 553 kB = 0 MB 3153 Load Address: 00000000 3154 Entry Point: 00000000 3155 Verifying Checksum ... OK 3156 Loading Ramdisk ... OK 3157 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 3158 Boot arguments: root=/dev/ram 3159 time_init: decrementer frequency = 187500000/60 3160 Calibrating delay loop... 49.77 BogoMIPS 3161 ... 3162 RAMDISK: Compressed image found at block 0 3163 VFS: Mounted root (ext2 filesystem). 3164 3165 bash# 3166 3167Boot Linux and pass a flat device tree: 3168----------- 3169 3170First, U-Boot must be compiled with the appropriate defines. See the section 3171titled "Linux Kernel Interface" above for a more in depth explanation. The 3172following is an example of how to start a kernel and pass an updated 3173flat device tree: 3174 3175=> print oftaddr 3176oftaddr=0x300000 3177=> print oft 3178oft=oftrees/mpc8540ads.dtb 3179=> tftp $oftaddr $oft 3180Speed: 1000, full duplex 3181Using TSEC0 device 3182TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3183Filename 'oftrees/mpc8540ads.dtb'. 3184Load address: 0x300000 3185Loading: # 3186done 3187Bytes transferred = 4106 (100a hex) 3188=> tftp $loadaddr $bootfile 3189Speed: 1000, full duplex 3190Using TSEC0 device 3191TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3192Filename 'uImage'. 3193Load address: 0x200000 3194Loading:############ 3195done 3196Bytes transferred = 1029407 (fb51f hex) 3197=> print loadaddr 3198loadaddr=200000 3199=> print oftaddr 3200oftaddr=0x300000 3201=> bootm $loadaddr - $oftaddr 3202## Booting image at 00200000 ... 3203 Image Name: Linux-2.6.17-dirty 3204 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3205 Data Size: 1029343 Bytes = 1005.2 kB 3206 Load Address: 00000000 3207 Entry Point: 00000000 3208 Verifying Checksum ... OK 3209 Uncompressing Kernel Image ... OK 3210Booting using flat device tree at 0x300000 3211Using MPC85xx ADS machine description 3212Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3213[snip] 3214 3215 3216More About U-Boot Image Types: 3217------------------------------ 3218 3219U-Boot supports the following image types: 3220 3221 "Standalone Programs" are directly runnable in the environment 3222 provided by U-Boot; it is expected that (if they behave 3223 well) you can continue to work in U-Boot after return from 3224 the Standalone Program. 3225 "OS Kernel Images" are usually images of some Embedded OS which 3226 will take over control completely. Usually these programs 3227 will install their own set of exception handlers, device 3228 drivers, set up the MMU, etc. - this means, that you cannot 3229 expect to re-enter U-Boot except by resetting the CPU. 3230 "RAMDisk Images" are more or less just data blocks, and their 3231 parameters (address, size) are passed to an OS kernel that is 3232 being started. 3233 "Multi-File Images" contain several images, typically an OS 3234 (Linux) kernel image and one or more data images like 3235 RAMDisks. This construct is useful for instance when you want 3236 to boot over the network using BOOTP etc., where the boot 3237 server provides just a single image file, but you want to get 3238 for instance an OS kernel and a RAMDisk image. 3239 3240 "Multi-File Images" start with a list of image sizes, each 3241 image size (in bytes) specified by an "uint32_t" in network 3242 byte order. This list is terminated by an "(uint32_t)0". 3243 Immediately after the terminating 0 follow the images, one by 3244 one, all aligned on "uint32_t" boundaries (size rounded up to 3245 a multiple of 4 bytes). 3246 3247 "Firmware Images" are binary images containing firmware (like 3248 U-Boot or FPGA images) which usually will be programmed to 3249 flash memory. 3250 3251 "Script files" are command sequences that will be executed by 3252 U-Boot's command interpreter; this feature is especially 3253 useful when you configure U-Boot to use a real shell (hush) 3254 as command interpreter. 3255 3256 3257Standalone HOWTO: 3258================= 3259 3260One of the features of U-Boot is that you can dynamically load and 3261run "standalone" applications, which can use some resources of 3262U-Boot like console I/O functions or interrupt services. 3263 3264Two simple examples are included with the sources: 3265 3266"Hello World" Demo: 3267------------------- 3268 3269'examples/hello_world.c' contains a small "Hello World" Demo 3270application; it is automatically compiled when you build U-Boot. 3271It's configured to run at address 0x00040004, so you can play with it 3272like that: 3273 3274 => loads 3275 ## Ready for S-Record download ... 3276 ~>examples/hello_world.srec 3277 1 2 3 4 5 6 7 8 9 10 11 ... 3278 [file transfer complete] 3279 [connected] 3280 ## Start Addr = 0x00040004 3281 3282 => go 40004 Hello World! This is a test. 3283 ## Starting application at 0x00040004 ... 3284 Hello World 3285 argc = 7 3286 argv[0] = "40004" 3287 argv[1] = "Hello" 3288 argv[2] = "World!" 3289 argv[3] = "This" 3290 argv[4] = "is" 3291 argv[5] = "a" 3292 argv[6] = "test." 3293 argv[7] = "<NULL>" 3294 Hit any key to exit ... 3295 3296 ## Application terminated, rc = 0x0 3297 3298Another example, which demonstrates how to register a CPM interrupt 3299handler with the U-Boot code, can be found in 'examples/timer.c'. 3300Here, a CPM timer is set up to generate an interrupt every second. 3301The interrupt service routine is trivial, just printing a '.' 3302character, but this is just a demo program. The application can be 3303controlled by the following keys: 3304 3305 ? - print current values og the CPM Timer registers 3306 b - enable interrupts and start timer 3307 e - stop timer and disable interrupts 3308 q - quit application 3309 3310 => loads 3311 ## Ready for S-Record download ... 3312 ~>examples/timer.srec 3313 1 2 3 4 5 6 7 8 9 10 11 ... 3314 [file transfer complete] 3315 [connected] 3316 ## Start Addr = 0x00040004 3317 3318 => go 40004 3319 ## Starting application at 0x00040004 ... 3320 TIMERS=0xfff00980 3321 Using timer 1 3322 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 3323 3324Hit 'b': 3325 [q, b, e, ?] Set interval 1000000 us 3326 Enabling timer 3327Hit '?': 3328 [q, b, e, ?] ........ 3329 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 3330Hit '?': 3331 [q, b, e, ?] . 3332 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 3333Hit '?': 3334 [q, b, e, ?] . 3335 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 3336Hit '?': 3337 [q, b, e, ?] . 3338 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 3339Hit 'e': 3340 [q, b, e, ?] ...Stopping timer 3341Hit 'q': 3342 [q, b, e, ?] ## Application terminated, rc = 0x0 3343 3344 3345Minicom warning: 3346================ 3347 3348Over time, many people have reported problems when trying to use the 3349"minicom" terminal emulation program for serial download. I (wd) 3350consider minicom to be broken, and recommend not to use it. Under 3351Unix, I recommend to use C-Kermit for general purpose use (and 3352especially for kermit binary protocol download ("loadb" command), and 3353use "cu" for S-Record download ("loads" command). 3354 3355Nevertheless, if you absolutely want to use it try adding this 3356configuration to your "File transfer protocols" section: 3357 3358 Name Program Name U/D FullScr IO-Red. Multi 3359 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 3360 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 3361 3362 3363NetBSD Notes: 3364============= 3365 3366Starting at version 0.9.2, U-Boot supports NetBSD both as host 3367(build U-Boot) and target system (boots NetBSD/mpc8xx). 3368 3369Building requires a cross environment; it is known to work on 3370NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 3371need gmake since the Makefiles are not compatible with BSD make). 3372Note that the cross-powerpc package does not install include files; 3373attempting to build U-Boot will fail because <machine/ansi.h> is 3374missing. This file has to be installed and patched manually: 3375 3376 # cd /usr/pkg/cross/powerpc-netbsd/include 3377 # mkdir powerpc 3378 # ln -s powerpc machine 3379 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 3380 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 3381 3382Native builds *don't* work due to incompatibilities between native 3383and U-Boot include files. 3384 3385Booting assumes that (the first part of) the image booted is a 3386stage-2 loader which in turn loads and then invokes the kernel 3387proper. Loader sources will eventually appear in the NetBSD source 3388tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 3389meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 3390 3391 3392Implementation Internals: 3393========================= 3394 3395The following is not intended to be a complete description of every 3396implementation detail. However, it should help to understand the 3397inner workings of U-Boot and make it easier to port it to custom 3398hardware. 3399 3400 3401Initial Stack, Global Data: 3402--------------------------- 3403 3404The implementation of U-Boot is complicated by the fact that U-Boot 3405starts running out of ROM (flash memory), usually without access to 3406system RAM (because the memory controller is not initialized yet). 3407This means that we don't have writable Data or BSS segments, and BSS 3408is not initialized as zero. To be able to get a C environment working 3409at all, we have to allocate at least a minimal stack. Implementation 3410options for this are defined and restricted by the CPU used: Some CPU 3411models provide on-chip memory (like the IMMR area on MPC8xx and 3412MPC826x processors), on others (parts of) the data cache can be 3413locked as (mis-) used as memory, etc. 3414 3415 Chris Hallinan posted a good summary of these issues to the 3416 u-boot-users mailing list: 3417 3418 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 3419 From: "Chris Hallinan" <clh@net1plus.com> 3420 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 3421 ... 3422 3423 Correct me if I'm wrong, folks, but the way I understand it 3424 is this: Using DCACHE as initial RAM for Stack, etc, does not 3425 require any physical RAM backing up the cache. The cleverness 3426 is that the cache is being used as a temporary supply of 3427 necessary storage before the SDRAM controller is setup. It's 3428 beyond the scope of this list to expain the details, but you 3429 can see how this works by studying the cache architecture and 3430 operation in the architecture and processor-specific manuals. 3431 3432 OCM is On Chip Memory, which I believe the 405GP has 4K. It 3433 is another option for the system designer to use as an 3434 initial stack/ram area prior to SDRAM being available. Either 3435 option should work for you. Using CS 4 should be fine if your 3436 board designers haven't used it for something that would 3437 cause you grief during the initial boot! It is frequently not 3438 used. 3439 3440 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 3441 with your processor/board/system design. The default value 3442 you will find in any recent u-boot distribution in 3443 walnut.h should work for you. I'd set it to a value larger 3444 than your SDRAM module. If you have a 64MB SDRAM module, set 3445 it above 400_0000. Just make sure your board has no resources 3446 that are supposed to respond to that address! That code in 3447 start.S has been around a while and should work as is when 3448 you get the config right. 3449 3450 -Chris Hallinan 3451 DS4.COM, Inc. 3452 3453It is essential to remember this, since it has some impact on the C 3454code for the initialization procedures: 3455 3456* Initialized global data (data segment) is read-only. Do not attempt 3457 to write it. 3458 3459* Do not use any unitialized global data (or implicitely initialized 3460 as zero data - BSS segment) at all - this is undefined, initiali- 3461 zation is performed later (when relocating to RAM). 3462 3463* Stack space is very limited. Avoid big data buffers or things like 3464 that. 3465 3466Having only the stack as writable memory limits means we cannot use 3467normal global data to share information beween the code. But it 3468turned out that the implementation of U-Boot can be greatly 3469simplified by making a global data structure (gd_t) available to all 3470functions. We could pass a pointer to this data as argument to _all_ 3471functions, but this would bloat the code. Instead we use a feature of 3472the GCC compiler (Global Register Variables) to share the data: we 3473place a pointer (gd) to the global data into a register which we 3474reserve for this purpose. 3475 3476When choosing a register for such a purpose we are restricted by the 3477relevant (E)ABI specifications for the current architecture, and by 3478GCC's implementation. 3479 3480For PowerPC, the following registers have specific use: 3481 R1: stack pointer 3482 R2: TOC pointer 3483 R3-R4: parameter passing and return values 3484 R5-R10: parameter passing 3485 R13: small data area pointer 3486 R30: GOT pointer 3487 R31: frame pointer 3488 3489 (U-Boot also uses R14 as internal GOT pointer.) 3490 3491 ==> U-Boot will use R29 to hold a pointer to the global data 3492 3493 Note: on PPC, we could use a static initializer (since the 3494 address of the global data structure is known at compile time), 3495 but it turned out that reserving a register results in somewhat 3496 smaller code - although the code savings are not that big (on 3497 average for all boards 752 bytes for the whole U-Boot image, 3498 624 text + 127 data). 3499 3500On ARM, the following registers are used: 3501 3502 R0: function argument word/integer result 3503 R1-R3: function argument word 3504 R9: GOT pointer 3505 R10: stack limit (used only if stack checking if enabled) 3506 R11: argument (frame) pointer 3507 R12: temporary workspace 3508 R13: stack pointer 3509 R14: link register 3510 R15: program counter 3511 3512 ==> U-Boot will use R8 to hold a pointer to the global data 3513 3514NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 3515or current versions of GCC may "optimize" the code too much. 3516 3517Memory Management: 3518------------------ 3519 3520U-Boot runs in system state and uses physical addresses, i.e. the 3521MMU is not used either for address mapping nor for memory protection. 3522 3523The available memory is mapped to fixed addresses using the memory 3524controller. In this process, a contiguous block is formed for each 3525memory type (Flash, SDRAM, SRAM), even when it consists of several 3526physical memory banks. 3527 3528U-Boot is installed in the first 128 kB of the first Flash bank (on 3529TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 3530booting and sizing and initializing DRAM, the code relocates itself 3531to the upper end of DRAM. Immediately below the U-Boot code some 3532memory is reserved for use by malloc() [see CFG_MALLOC_LEN 3533configuration setting]. Below that, a structure with global Board 3534Info data is placed, followed by the stack (growing downward). 3535 3536Additionally, some exception handler code is copied to the low 8 kB 3537of DRAM (0x00000000 ... 0x00001FFF). 3538 3539So a typical memory configuration with 16 MB of DRAM could look like 3540this: 3541 3542 0x0000 0000 Exception Vector code 3543 : 3544 0x0000 1FFF 3545 0x0000 2000 Free for Application Use 3546 : 3547 : 3548 3549 : 3550 : 3551 0x00FB FF20 Monitor Stack (Growing downward) 3552 0x00FB FFAC Board Info Data and permanent copy of global data 3553 0x00FC 0000 Malloc Arena 3554 : 3555 0x00FD FFFF 3556 0x00FE 0000 RAM Copy of Monitor Code 3557 ... eventually: LCD or video framebuffer 3558 ... eventually: pRAM (Protected RAM - unchanged by reset) 3559 0x00FF FFFF [End of RAM] 3560 3561 3562System Initialization: 3563---------------------- 3564 3565In the reset configuration, U-Boot starts at the reset entry point 3566(on most PowerPC systens at address 0x00000100). Because of the reset 3567configuration for CS0# this is a mirror of the onboard Flash memory. 3568To be able to re-map memory U-Boot then jumps to its link address. 3569To be able to implement the initialization code in C, a (small!) 3570initial stack is set up in the internal Dual Ported RAM (in case CPUs 3571which provide such a feature like MPC8xx or MPC8260), or in a locked 3572part of the data cache. After that, U-Boot initializes the CPU core, 3573the caches and the SIU. 3574 3575Next, all (potentially) available memory banks are mapped using a 3576preliminary mapping. For example, we put them on 512 MB boundaries 3577(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3578on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3579programmed for SDRAM access. Using the temporary configuration, a 3580simple memory test is run that determines the size of the SDRAM 3581banks. 3582 3583When there is more than one SDRAM bank, and the banks are of 3584different size, the largest is mapped first. For equal size, the first 3585bank (CS2#) is mapped first. The first mapping is always for address 35860x00000000, with any additional banks following immediately to create 3587contiguous memory starting from 0. 3588 3589Then, the monitor installs itself at the upper end of the SDRAM area 3590and allocates memory for use by malloc() and for the global Board 3591Info data; also, the exception vector code is copied to the low RAM 3592pages, and the final stack is set up. 3593 3594Only after this relocation will you have a "normal" C environment; 3595until that you are restricted in several ways, mostly because you are 3596running from ROM, and because the code will have to be relocated to a 3597new address in RAM. 3598 3599 3600U-Boot Porting Guide: 3601---------------------- 3602 3603[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3604list, October 2002] 3605 3606 3607int main (int argc, char *argv[]) 3608{ 3609 sighandler_t no_more_time; 3610 3611 signal (SIGALRM, no_more_time); 3612 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3613 3614 if (available_money > available_manpower) { 3615 pay consultant to port U-Boot; 3616 return 0; 3617 } 3618 3619 Download latest U-Boot source; 3620 3621 Subscribe to u-boot-users mailing list; 3622 3623 if (clueless) { 3624 email ("Hi, I am new to U-Boot, how do I get started?"); 3625 } 3626 3627 while (learning) { 3628 Read the README file in the top level directory; 3629 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3630 Read the source, Luke; 3631 } 3632 3633 if (available_money > toLocalCurrency ($2500)) { 3634 Buy a BDI2000; 3635 } else { 3636 Add a lot of aggravation and time; 3637 } 3638 3639 Create your own board support subdirectory; 3640 3641 Create your own board config file; 3642 3643 while (!running) { 3644 do { 3645 Add / modify source code; 3646 } until (compiles); 3647 Debug; 3648 if (clueless) 3649 email ("Hi, I am having problems..."); 3650 } 3651 Send patch file to Wolfgang; 3652 3653 return 0; 3654} 3655 3656void no_more_time (int sig) 3657{ 3658 hire_a_guru(); 3659} 3660 3661 3662Coding Standards: 3663----------------- 3664 3665All contributions to U-Boot should conform to the Linux kernel 3666coding style; see the file "Documentation/CodingStyle" and the script 3667"scripts/Lindent" in your Linux kernel source directory. In sources 3668originating from U-Boot a style corresponding to "Lindent -pcs" (adding 3669spaces before parameters to function calls) is actually used. 3670 3671Source files originating from a different project (for example the 3672MTD subsystem) are generally exempt from these guidelines and are not 3673reformated to ease subsequent migration to newer versions of those 3674sources. 3675 3676Please note that U-Boot is implemented in C (and to some small parts in 3677Assembler); no C++ is used, so please do not use C++ style comments (//) 3678in your code. 3679 3680Please also stick to the following formatting rules: 3681- remove any trailing white space 3682- use TAB characters for indentation, not spaces 3683- make sure NOT to use DOS '\r\n' line feeds 3684- do not add more than 2 empty lines to source files 3685- do not add trailing empty lines to source files 3686 3687Submissions which do not conform to the standards may be returned 3688with a request to reformat the changes. 3689 3690 3691Submitting Patches: 3692------------------- 3693 3694Since the number of patches for U-Boot is growing, we need to 3695establish some rules. Submissions which do not conform to these rules 3696may be rejected, even when they contain important and valuable stuff. 3697 3698Patches shall be sent to the u-boot-users mailing list. 3699 3700When you send a patch, please include the following information with 3701it: 3702 3703* For bug fixes: a description of the bug and how your patch fixes 3704 this bug. Please try to include a way of demonstrating that the 3705 patch actually fixes something. 3706 3707* For new features: a description of the feature and your 3708 implementation. 3709 3710* A CHANGELOG entry as plaintext (separate from the patch) 3711 3712* For major contributions, your entry to the CREDITS file 3713 3714* When you add support for a new board, don't forget to add this 3715 board to the MAKEALL script, too. 3716 3717* If your patch adds new configuration options, don't forget to 3718 document these in the README file. 3719 3720* The patch itself. If you are accessing the CVS repository use "cvs 3721 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your 3722 version of diff does not support these options, then get the latest 3723 version of GNU diff. 3724 3725 The current directory when running this command shall be the top 3726 level directory of the U-Boot source tree, or it's parent directory 3727 (i. e. please make sure that your patch includes sufficient 3728 directory information for the affected files). 3729 3730 We accept patches as plain text, MIME attachments or as uuencoded 3731 gzipped text. 3732 3733* If one logical set of modifications affects or creates several 3734 files, all these changes shall be submitted in a SINGLE patch file. 3735 3736* Changesets that contain different, unrelated modifications shall be 3737 submitted as SEPARATE patches, one patch per changeset. 3738 3739 3740Notes: 3741 3742* Before sending the patch, run the MAKEALL script on your patched 3743 source tree and make sure that no errors or warnings are reported 3744 for any of the boards. 3745 3746* Keep your modifications to the necessary minimum: A patch 3747 containing several unrelated changes or arbitrary reformats will be 3748 returned with a request to re-formatting / split it. 3749 3750* If you modify existing code, make sure that your new code does not 3751 add to the memory footprint of the code ;-) Small is beautiful! 3752 When adding new features, these should compile conditionally only 3753 (using #ifdef), and the resulting code with the new feature 3754 disabled must not need more memory than the old code without your 3755 modification. 3756 3757* Remember that there is a size limit of 40 kB per message on the 3758 u-boot-users mailing list. Compression may help. 3759