1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG and CREDITS files to find out 38who contributed the specific port. The boards.cfg file lists board 39maintainers. 40 41Note: There is no CHANGELOG file in the actual U-Boot source tree; 42it can be created dynamically from the Git log using: 43 44 make CHANGELOG 45 46 47Where to get help: 48================== 49 50In case you have questions about, problems with or contributions for 51U-Boot you should send a message to the U-Boot mailing list at 52<u-boot@lists.denx.de>. There is also an archive of previous traffic 53on the mailing list - please search the archive before asking FAQ's. 54Please see http://lists.denx.de/pipermail/u-boot and 55http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 56 57 58Where to get source code: 59========================= 60 61The U-Boot source code is maintained in the git repository at 62git://www.denx.de/git/u-boot.git ; you can browse it online at 63http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 64 65The "snapshot" links on this page allow you to download tarballs of 66any version you might be interested in. Official releases are also 67available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 68directory. 69 70Pre-built (and tested) images are available from 71ftp://ftp.denx.de/pub/u-boot/images/ 72 73 74Where we come from: 75=================== 76 77- start from 8xxrom sources 78- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 79- clean up code 80- make it easier to add custom boards 81- make it possible to add other [PowerPC] CPUs 82- extend functions, especially: 83 * Provide extended interface to Linux boot loader 84 * S-Record download 85 * network boot 86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 87- create ARMBoot project (http://sourceforge.net/projects/armboot) 88- add other CPU families (starting with ARM) 89- create U-Boot project (http://sourceforge.net/projects/u-boot) 90- current project page: see http://www.denx.de/wiki/U-Boot 91 92 93Names and Spelling: 94=================== 95 96The "official" name of this project is "Das U-Boot". The spelling 97"U-Boot" shall be used in all written text (documentation, comments 98in source files etc.). Example: 99 100 This is the README file for the U-Boot project. 101 102File names etc. shall be based on the string "u-boot". Examples: 103 104 include/asm-ppc/u-boot.h 105 106 #include <asm/u-boot.h> 107 108Variable names, preprocessor constants etc. shall be either based on 109the string "u_boot" or on "U_BOOT". Example: 110 111 U_BOOT_VERSION u_boot_logo 112 IH_OS_U_BOOT u_boot_hush_start 113 114 115Versioning: 116=========== 117 118Starting with the release in October 2008, the names of the releases 119were changed from numerical release numbers without deeper meaning 120into a time stamp based numbering. Regular releases are identified by 121names consisting of the calendar year and month of the release date. 122Additional fields (if present) indicate release candidates or bug fix 123releases in "stable" maintenance trees. 124 125Examples: 126 U-Boot v2009.11 - Release November 2009 127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 129 130 131Directory Hierarchy: 132==================== 133 134/arch Architecture specific files 135 /arc Files generic to ARC architecture 136 /cpu CPU specific files 137 /arc700 Files specific to ARC 700 CPUs 138 /lib Architecture specific library files 139 /arm Files generic to ARM architecture 140 /cpu CPU specific files 141 /arm720t Files specific to ARM 720 CPUs 142 /arm920t Files specific to ARM 920 CPUs 143 /at91 Files specific to Atmel AT91RM9200 CPU 144 /imx Files specific to Freescale MC9328 i.MX CPUs 145 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 146 /arm926ejs Files specific to ARM 926 CPUs 147 /arm1136 Files specific to ARM 1136 CPUs 148 /pxa Files specific to Intel XScale PXA CPUs 149 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 150 /lib Architecture specific library files 151 /avr32 Files generic to AVR32 architecture 152 /cpu CPU specific files 153 /lib Architecture specific library files 154 /blackfin Files generic to Analog Devices Blackfin architecture 155 /cpu CPU specific files 156 /lib Architecture specific library files 157 /m68k Files generic to m68k architecture 158 /cpu CPU specific files 159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 164 /lib Architecture specific library files 165 /microblaze Files generic to microblaze architecture 166 /cpu CPU specific files 167 /lib Architecture specific library files 168 /mips Files generic to MIPS architecture 169 /cpu CPU specific files 170 /mips32 Files specific to MIPS32 CPUs 171 /mips64 Files specific to MIPS64 CPUs 172 /lib Architecture specific library files 173 /nds32 Files generic to NDS32 architecture 174 /cpu CPU specific files 175 /n1213 Files specific to Andes Technology N1213 CPUs 176 /lib Architecture specific library files 177 /nios2 Files generic to Altera NIOS2 architecture 178 /cpu CPU specific files 179 /lib Architecture specific library files 180 /openrisc Files generic to OpenRISC architecture 181 /cpu CPU specific files 182 /lib Architecture specific library files 183 /powerpc Files generic to PowerPC architecture 184 /cpu CPU specific files 185 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 186 /mpc5xx Files specific to Freescale MPC5xx CPUs 187 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 188 /mpc8xx Files specific to Freescale MPC8xx CPUs 189 /mpc824x Files specific to Freescale MPC824x CPUs 190 /mpc8260 Files specific to Freescale MPC8260 CPUs 191 /mpc85xx Files specific to Freescale MPC85xx CPUs 192 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 193 /lib Architecture specific library files 194 /sh Files generic to SH architecture 195 /cpu CPU specific files 196 /sh2 Files specific to sh2 CPUs 197 /sh3 Files specific to sh3 CPUs 198 /sh4 Files specific to sh4 CPUs 199 /lib Architecture specific library files 200 /sparc Files generic to SPARC architecture 201 /cpu CPU specific files 202 /leon2 Files specific to Gaisler LEON2 SPARC CPU 203 /leon3 Files specific to Gaisler LEON3 SPARC CPU 204 /lib Architecture specific library files 205 /x86 Files generic to x86 architecture 206 /cpu CPU specific files 207 /lib Architecture specific library files 208/api Machine/arch independent API for external apps 209/board Board dependent files 210/common Misc architecture independent functions 211/disk Code for disk drive partition handling 212/doc Documentation (don't expect too much) 213/drivers Commonly used device drivers 214/dts Contains Makefile for building internal U-Boot fdt. 215/examples Example code for standalone applications, etc. 216/fs Filesystem code (cramfs, ext2, jffs2, etc.) 217/include Header Files 218/lib Files generic to all architectures 219 /libfdt Library files to support flattened device trees 220 /lzma Library files to support LZMA decompression 221 /lzo Library files to support LZO decompression 222/net Networking code 223/post Power On Self Test 224/spl Secondary Program Loader framework 225/tools Tools to build S-Record or U-Boot images, etc. 226 227Software Configuration: 228======================= 229 230Configuration is usually done using C preprocessor defines; the 231rationale behind that is to avoid dead code whenever possible. 232 233There are two classes of configuration variables: 234 235* Configuration _OPTIONS_: 236 These are selectable by the user and have names beginning with 237 "CONFIG_". 238 239* Configuration _SETTINGS_: 240 These depend on the hardware etc. and should not be meddled with if 241 you don't know what you're doing; they have names beginning with 242 "CONFIG_SYS_". 243 244Later we will add a configuration tool - probably similar to or even 245identical to what's used for the Linux kernel. Right now, we have to 246do the configuration by hand, which means creating some symbolic 247links and editing some configuration files. We use the TQM8xxL boards 248as an example here. 249 250 251Selection of Processor Architecture and Board Type: 252--------------------------------------------------- 253 254For all supported boards there are ready-to-use default 255configurations available; just type "make <board_name>_defconfig". 256 257Example: For a TQM823L module type: 258 259 cd u-boot 260 make TQM823L_defconfig 261 262For the Cogent platform, you need to specify the CPU type as well; 263e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent 264directory according to the instructions in cogent/README. 265 266 267Sandbox Environment: 268-------------------- 269 270U-Boot can be built natively to run on a Linux host using the 'sandbox' 271board. This allows feature development which is not board- or architecture- 272specific to be undertaken on a native platform. The sandbox is also used to 273run some of U-Boot's tests. 274 275See board/sandbox/README.sandbox for more details. 276 277 278Configuration Options: 279---------------------- 280 281Configuration depends on the combination of board and CPU type; all 282such information is kept in a configuration file 283"include/configs/<board_name>.h". 284 285Example: For a TQM823L module, all configuration settings are in 286"include/configs/TQM823L.h". 287 288 289Many of the options are named exactly as the corresponding Linux 290kernel configuration options. The intention is to make it easier to 291build a config tool - later. 292 293 294The following options need to be configured: 295 296- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 297 298- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 299 300- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 301 Define exactly one, e.g. CONFIG_ATSTK1002 302 303- CPU Module Type: (if CONFIG_COGENT is defined) 304 Define exactly one of 305 CONFIG_CMA286_60_OLD 306--- FIXME --- not tested yet: 307 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 308 CONFIG_CMA287_23, CONFIG_CMA287_50 309 310- Motherboard Type: (if CONFIG_COGENT is defined) 311 Define exactly one of 312 CONFIG_CMA101, CONFIG_CMA102 313 314- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 315 Define one or more of 316 CONFIG_CMA302 317 318- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 319 Define one or more of 320 CONFIG_LCD_HEARTBEAT - update a character position on 321 the LCD display every second with 322 a "rotator" |\-/|\-/ 323 324- Marvell Family Member 325 CONFIG_SYS_MVFS - define it if you want to enable 326 multiple fs option at one time 327 for marvell soc family 328 329- MPC824X Family Member (if CONFIG_MPC824X is defined) 330 Define exactly one of 331 CONFIG_MPC8240, CONFIG_MPC8245 332 333- 8xx CPU Options: (if using an MPC8xx CPU) 334 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 335 get_gclk_freq() cannot work 336 e.g. if there is no 32KHz 337 reference PIT/RTC clock 338 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 339 or XTAL/EXTAL) 340 341- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 342 CONFIG_SYS_8xx_CPUCLK_MIN 343 CONFIG_SYS_8xx_CPUCLK_MAX 344 CONFIG_8xx_CPUCLK_DEFAULT 345 See doc/README.MPC866 346 347 CONFIG_SYS_MEASURE_CPUCLK 348 349 Define this to measure the actual CPU clock instead 350 of relying on the correctness of the configured 351 values. Mostly useful for board bringup to make sure 352 the PLL is locked at the intended frequency. Note 353 that this requires a (stable) reference clock (32 kHz 354 RTC clock or CONFIG_SYS_8XX_XIN) 355 356 CONFIG_SYS_DELAYED_ICACHE 357 358 Define this option if you want to enable the 359 ICache only when Code runs from RAM. 360 361- 85xx CPU Options: 362 CONFIG_SYS_PPC64 363 364 Specifies that the core is a 64-bit PowerPC implementation (implements 365 the "64" category of the Power ISA). This is necessary for ePAPR 366 compliance, among other possible reasons. 367 368 CONFIG_SYS_FSL_TBCLK_DIV 369 370 Defines the core time base clock divider ratio compared to the 371 system clock. On most PQ3 devices this is 8, on newer QorIQ 372 devices it can be 16 or 32. The ratio varies from SoC to Soc. 373 374 CONFIG_SYS_FSL_PCIE_COMPAT 375 376 Defines the string to utilize when trying to match PCIe device 377 tree nodes for the given platform. 378 379 CONFIG_SYS_PPC_E500_DEBUG_TLB 380 381 Enables a temporary TLB entry to be used during boot to work 382 around limitations in e500v1 and e500v2 external debugger 383 support. This reduces the portions of the boot code where 384 breakpoints and single stepping do not work. The value of this 385 symbol should be set to the TLB1 entry to be used for this 386 purpose. 387 388 CONFIG_SYS_FSL_ERRATUM_A004510 389 390 Enables a workaround for erratum A004510. If set, 391 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 392 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 393 394 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 395 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 396 397 Defines one or two SoC revisions (low 8 bits of SVR) 398 for which the A004510 workaround should be applied. 399 400 The rest of SVR is either not relevant to the decision 401 of whether the erratum is present (e.g. p2040 versus 402 p2041) or is implied by the build target, which controls 403 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 404 405 See Freescale App Note 4493 for more information about 406 this erratum. 407 408 CONFIG_A003399_NOR_WORKAROUND 409 Enables a workaround for IFC erratum A003399. It is only 410 requred during NOR boot. 411 412 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 413 414 This is the value to write into CCSR offset 0x18600 415 according to the A004510 workaround. 416 417 CONFIG_SYS_FSL_DSP_DDR_ADDR 418 This value denotes start offset of DDR memory which is 419 connected exclusively to the DSP cores. 420 421 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 422 This value denotes start offset of M2 memory 423 which is directly connected to the DSP core. 424 425 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 426 This value denotes start offset of M3 memory which is directly 427 connected to the DSP core. 428 429 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 430 This value denotes start offset of DSP CCSR space. 431 432 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 433 Single Source Clock is clocking mode present in some of FSL SoC's. 434 In this mode, a single differential clock is used to supply 435 clocks to the sysclock, ddrclock and usbclock. 436 437 CONFIG_SYS_CPC_REINIT_F 438 This CONFIG is defined when the CPC is configured as SRAM at the 439 time of U-boot entry and is required to be re-initialized. 440 441 CONFIG_DEEP_SLEEP 442 Inidcates this SoC supports deep sleep feature. If deep sleep is 443 supported, core will start to execute uboot when wakes up. 444 445- Generic CPU options: 446 CONFIG_SYS_GENERIC_GLOBAL_DATA 447 Defines global data is initialized in generic board board_init_f(). 448 If this macro is defined, global data is created and cleared in 449 generic board board_init_f(). Without this macro, architecture/board 450 should initialize global data before calling board_init_f(). 451 452 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 453 454 Defines the endianess of the CPU. Implementation of those 455 values is arch specific. 456 457 CONFIG_SYS_FSL_DDR 458 Freescale DDR driver in use. This type of DDR controller is 459 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 460 SoCs. 461 462 CONFIG_SYS_FSL_DDR_ADDR 463 Freescale DDR memory-mapped register base. 464 465 CONFIG_SYS_FSL_DDR_EMU 466 Specify emulator support for DDR. Some DDR features such as 467 deskew training are not available. 468 469 CONFIG_SYS_FSL_DDRC_GEN1 470 Freescale DDR1 controller. 471 472 CONFIG_SYS_FSL_DDRC_GEN2 473 Freescale DDR2 controller. 474 475 CONFIG_SYS_FSL_DDRC_GEN3 476 Freescale DDR3 controller. 477 478 CONFIG_SYS_FSL_DDRC_GEN4 479 Freescale DDR4 controller. 480 481 CONFIG_SYS_FSL_DDRC_ARM_GEN3 482 Freescale DDR3 controller for ARM-based SoCs. 483 484 CONFIG_SYS_FSL_DDR1 485 Board config to use DDR1. It can be enabled for SoCs with 486 Freescale DDR1 or DDR2 controllers, depending on the board 487 implemetation. 488 489 CONFIG_SYS_FSL_DDR2 490 Board config to use DDR2. It can be eanbeld for SoCs with 491 Freescale DDR2 or DDR3 controllers, depending on the board 492 implementation. 493 494 CONFIG_SYS_FSL_DDR3 495 Board config to use DDR3. It can be enabled for SoCs with 496 Freescale DDR3 or DDR3L controllers. 497 498 CONFIG_SYS_FSL_DDR3L 499 Board config to use DDR3L. It can be enabled for SoCs with 500 DDR3L controllers. 501 502 CONFIG_SYS_FSL_DDR4 503 Board config to use DDR4. It can be enabled for SoCs with 504 DDR4 controllers. 505 506 CONFIG_SYS_FSL_IFC_BE 507 Defines the IFC controller register space as Big Endian 508 509 CONFIG_SYS_FSL_IFC_LE 510 Defines the IFC controller register space as Little Endian 511 512 CONFIG_SYS_FSL_PBL_PBI 513 It enables addition of RCW (Power on reset configuration) in built image. 514 Please refer doc/README.pblimage for more details 515 516 CONFIG_SYS_FSL_PBL_RCW 517 It adds PBI(pre-boot instructions) commands in u-boot build image. 518 PBI commands can be used to configure SoC before it starts the execution. 519 Please refer doc/README.pblimage for more details 520 521 CONFIG_SPL_FSL_PBL 522 It adds a target to create boot binary having SPL binary in PBI format 523 concatenated with u-boot binary. 524 525 CONFIG_SYS_FSL_DDR_BE 526 Defines the DDR controller register space as Big Endian 527 528 CONFIG_SYS_FSL_DDR_LE 529 Defines the DDR controller register space as Little Endian 530 531 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 532 Physical address from the view of DDR controllers. It is the 533 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 534 it could be different for ARM SoCs. 535 536 CONFIG_SYS_FSL_DDR_INTLV_256B 537 DDR controller interleaving on 256-byte. This is a special 538 interleaving mode, handled by Dickens for Freescale layerscape 539 SoCs with ARM core. 540 541 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 542 Number of controllers used as main memory. 543 544 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 545 Number of controllers used for other than main memory. 546 547- Intel Monahans options: 548 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 549 550 Defines the Monahans run mode to oscillator 551 ratio. Valid values are 8, 16, 24, 31. The core 552 frequency is this value multiplied by 13 MHz. 553 554 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 555 556 Defines the Monahans turbo mode to oscillator 557 ratio. Valid values are 1 (default if undefined) and 558 2. The core frequency as calculated above is multiplied 559 by this value. 560 561- MIPS CPU options: 562 CONFIG_SYS_INIT_SP_OFFSET 563 564 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 565 pointer. This is needed for the temporary stack before 566 relocation. 567 568 CONFIG_SYS_MIPS_CACHE_MODE 569 570 Cache operation mode for the MIPS CPU. 571 See also arch/mips/include/asm/mipsregs.h. 572 Possible values are: 573 CONF_CM_CACHABLE_NO_WA 574 CONF_CM_CACHABLE_WA 575 CONF_CM_UNCACHED 576 CONF_CM_CACHABLE_NONCOHERENT 577 CONF_CM_CACHABLE_CE 578 CONF_CM_CACHABLE_COW 579 CONF_CM_CACHABLE_CUW 580 CONF_CM_CACHABLE_ACCELERATED 581 582 CONFIG_SYS_XWAY_EBU_BOOTCFG 583 584 Special option for Lantiq XWAY SoCs for booting from NOR flash. 585 See also arch/mips/cpu/mips32/start.S. 586 587 CONFIG_XWAY_SWAP_BYTES 588 589 Enable compilation of tools/xway-swap-bytes needed for Lantiq 590 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 591 be swapped if a flash programmer is used. 592 593- ARM options: 594 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 595 596 Select high exception vectors of the ARM core, e.g., do not 597 clear the V bit of the c1 register of CP15. 598 599 CONFIG_SYS_THUMB_BUILD 600 601 Use this flag to build U-Boot using the Thumb instruction 602 set for ARM architectures. Thumb instruction set provides 603 better code density. For ARM architectures that support 604 Thumb2 this flag will result in Thumb2 code generated by 605 GCC. 606 607 CONFIG_ARM_ERRATA_716044 608 CONFIG_ARM_ERRATA_742230 609 CONFIG_ARM_ERRATA_743622 610 CONFIG_ARM_ERRATA_751472 611 CONFIG_ARM_ERRATA_794072 612 CONFIG_ARM_ERRATA_761320 613 614 If set, the workarounds for these ARM errata are applied early 615 during U-Boot startup. Note that these options force the 616 workarounds to be applied; no CPU-type/version detection 617 exists, unlike the similar options in the Linux kernel. Do not 618 set these options unless they apply! 619 620- CPU timer options: 621 CONFIG_SYS_HZ 622 623 The frequency of the timer returned by get_timer(). 624 get_timer() must operate in milliseconds and this CONFIG 625 option must be set to 1000. 626 627- Linux Kernel Interface: 628 CONFIG_CLOCKS_IN_MHZ 629 630 U-Boot stores all clock information in Hz 631 internally. For binary compatibility with older Linux 632 kernels (which expect the clocks passed in the 633 bd_info data to be in MHz) the environment variable 634 "clocks_in_mhz" can be defined so that U-Boot 635 converts clock data to MHZ before passing it to the 636 Linux kernel. 637 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 638 "clocks_in_mhz=1" is automatically included in the 639 default environment. 640 641 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 642 643 When transferring memsize parameter to linux, some versions 644 expect it to be in bytes, others in MB. 645 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 646 647 CONFIG_OF_LIBFDT 648 649 New kernel versions are expecting firmware settings to be 650 passed using flattened device trees (based on open firmware 651 concepts). 652 653 CONFIG_OF_LIBFDT 654 * New libfdt-based support 655 * Adds the "fdt" command 656 * The bootm command automatically updates the fdt 657 658 OF_CPU - The proper name of the cpus node (only required for 659 MPC512X and MPC5xxx based boards). 660 OF_SOC - The proper name of the soc node (only required for 661 MPC512X and MPC5xxx based boards). 662 OF_TBCLK - The timebase frequency. 663 OF_STDOUT_PATH - The path to the console device 664 665 boards with QUICC Engines require OF_QE to set UCC MAC 666 addresses 667 668 CONFIG_OF_BOARD_SETUP 669 670 Board code has addition modification that it wants to make 671 to the flat device tree before handing it off to the kernel 672 673 CONFIG_OF_BOOT_CPU 674 675 This define fills in the correct boot CPU in the boot 676 param header, the default value is zero if undefined. 677 678 CONFIG_OF_IDE_FIXUP 679 680 U-Boot can detect if an IDE device is present or not. 681 If not, and this new config option is activated, U-Boot 682 removes the ATA node from the DTS before booting Linux, 683 so the Linux IDE driver does not probe the device and 684 crash. This is needed for buggy hardware (uc101) where 685 no pull down resistor is connected to the signal IDE5V_DD7. 686 687 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 688 689 This setting is mandatory for all boards that have only one 690 machine type and must be used to specify the machine type 691 number as it appears in the ARM machine registry 692 (see http://www.arm.linux.org.uk/developer/machines/). 693 Only boards that have multiple machine types supported 694 in a single configuration file and the machine type is 695 runtime discoverable, do not have to use this setting. 696 697- vxWorks boot parameters: 698 699 bootvx constructs a valid bootline using the following 700 environments variables: bootfile, ipaddr, serverip, hostname. 701 It loads the vxWorks image pointed bootfile. 702 703 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 704 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 705 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 706 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 707 708 CONFIG_SYS_VXWORKS_ADD_PARAMS 709 710 Add it at the end of the bootline. E.g "u=username pw=secret" 711 712 Note: If a "bootargs" environment is defined, it will overwride 713 the defaults discussed just above. 714 715- Cache Configuration: 716 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 717 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 718 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 719 720- Cache Configuration for ARM: 721 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 722 controller 723 CONFIG_SYS_PL310_BASE - Physical base address of PL310 724 controller register space 725 726- Serial Ports: 727 CONFIG_PL010_SERIAL 728 729 Define this if you want support for Amba PrimeCell PL010 UARTs. 730 731 CONFIG_PL011_SERIAL 732 733 Define this if you want support for Amba PrimeCell PL011 UARTs. 734 735 CONFIG_PL011_CLOCK 736 737 If you have Amba PrimeCell PL011 UARTs, set this variable to 738 the clock speed of the UARTs. 739 740 CONFIG_PL01x_PORTS 741 742 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 743 define this to a list of base addresses for each (supported) 744 port. See e.g. include/configs/versatile.h 745 746 CONFIG_PL011_SERIAL_RLCR 747 748 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 749 have separate receive and transmit line control registers. Set 750 this variable to initialize the extra register. 751 752 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 753 754 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 755 boot loader that has already initialized the UART. Define this 756 variable to flush the UART at init time. 757 758 CONFIG_SERIAL_HW_FLOW_CONTROL 759 760 Define this variable to enable hw flow control in serial driver. 761 Current user of this option is drivers/serial/nsl16550.c driver 762 763- Console Interface: 764 Depending on board, define exactly one serial port 765 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 766 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 767 console by defining CONFIG_8xx_CONS_NONE 768 769 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 770 port routines must be defined elsewhere 771 (i.e. serial_init(), serial_getc(), ...) 772 773 CONFIG_CFB_CONSOLE 774 Enables console device for a color framebuffer. Needs following 775 defines (cf. smiLynxEM, i8042) 776 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 777 (default big endian) 778 VIDEO_HW_RECTFILL graphic chip supports 779 rectangle fill 780 (cf. smiLynxEM) 781 VIDEO_HW_BITBLT graphic chip supports 782 bit-blit (cf. smiLynxEM) 783 VIDEO_VISIBLE_COLS visible pixel columns 784 (cols=pitch) 785 VIDEO_VISIBLE_ROWS visible pixel rows 786 VIDEO_PIXEL_SIZE bytes per pixel 787 VIDEO_DATA_FORMAT graphic data format 788 (0-5, cf. cfb_console.c) 789 VIDEO_FB_ADRS framebuffer address 790 VIDEO_KBD_INIT_FCT keyboard int fct 791 (i.e. i8042_kbd_init()) 792 VIDEO_TSTC_FCT test char fct 793 (i.e. i8042_tstc) 794 VIDEO_GETC_FCT get char fct 795 (i.e. i8042_getc) 796 CONFIG_CONSOLE_CURSOR cursor drawing on/off 797 (requires blink timer 798 cf. i8042.c) 799 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 800 CONFIG_CONSOLE_TIME display time/date info in 801 upper right corner 802 (requires CONFIG_CMD_DATE) 803 CONFIG_VIDEO_LOGO display Linux logo in 804 upper left corner 805 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 806 linux_logo.h for logo. 807 Requires CONFIG_VIDEO_LOGO 808 CONFIG_CONSOLE_EXTRA_INFO 809 additional board info beside 810 the logo 811 812 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 813 a limited number of ANSI escape sequences (cursor control, 814 erase functions and limited graphics rendition control). 815 816 When CONFIG_CFB_CONSOLE is defined, video console is 817 default i/o. Serial console can be forced with 818 environment 'console=serial'. 819 820 When CONFIG_SILENT_CONSOLE is defined, all console 821 messages (by U-Boot and Linux!) can be silenced with 822 the "silent" environment variable. See 823 doc/README.silent for more information. 824 825 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 826 is 0x00. 827 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 828 is 0xa0. 829 830- Console Baudrate: 831 CONFIG_BAUDRATE - in bps 832 Select one of the baudrates listed in 833 CONFIG_SYS_BAUDRATE_TABLE, see below. 834 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 835 836- Console Rx buffer length 837 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 838 the maximum receive buffer length for the SMC. 839 This option is actual only for 82xx and 8xx possible. 840 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 841 must be defined, to setup the maximum idle timeout for 842 the SMC. 843 844- Pre-Console Buffer: 845 Prior to the console being initialised (i.e. serial UART 846 initialised etc) all console output is silently discarded. 847 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 848 buffer any console messages prior to the console being 849 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 850 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 851 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 852 bytes are output before the console is initialised, the 853 earlier bytes are discarded. 854 855 'Sane' compilers will generate smaller code if 856 CONFIG_PRE_CON_BUF_SZ is a power of 2 857 858- Safe printf() functions 859 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 860 the printf() functions. These are defined in 861 include/vsprintf.h and include snprintf(), vsnprintf() and 862 so on. Code size increase is approximately 300-500 bytes. 863 If this option is not given then these functions will 864 silently discard their buffer size argument - this means 865 you are not getting any overflow checking in this case. 866 867- Boot Delay: CONFIG_BOOTDELAY - in seconds 868 Delay before automatically booting the default image; 869 set to -1 to disable autoboot. 870 set to -2 to autoboot with no delay and not check for abort 871 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 872 873 See doc/README.autoboot for these options that 874 work with CONFIG_BOOTDELAY. None are required. 875 CONFIG_BOOT_RETRY_TIME 876 CONFIG_BOOT_RETRY_MIN 877 CONFIG_AUTOBOOT_KEYED 878 CONFIG_AUTOBOOT_PROMPT 879 CONFIG_AUTOBOOT_DELAY_STR 880 CONFIG_AUTOBOOT_STOP_STR 881 CONFIG_AUTOBOOT_DELAY_STR2 882 CONFIG_AUTOBOOT_STOP_STR2 883 CONFIG_ZERO_BOOTDELAY_CHECK 884 CONFIG_RESET_TO_RETRY 885 886- Autoboot Command: 887 CONFIG_BOOTCOMMAND 888 Only needed when CONFIG_BOOTDELAY is enabled; 889 define a command string that is automatically executed 890 when no character is read on the console interface 891 within "Boot Delay" after reset. 892 893 CONFIG_BOOTARGS 894 This can be used to pass arguments to the bootm 895 command. The value of CONFIG_BOOTARGS goes into the 896 environment value "bootargs". 897 898 CONFIG_RAMBOOT and CONFIG_NFSBOOT 899 The value of these goes into the environment as 900 "ramboot" and "nfsboot" respectively, and can be used 901 as a convenience, when switching between booting from 902 RAM and NFS. 903 904- Bootcount: 905 CONFIG_BOOTCOUNT_LIMIT 906 Implements a mechanism for detecting a repeating reboot 907 cycle, see: 908 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 909 910 CONFIG_BOOTCOUNT_ENV 911 If no softreset save registers are found on the hardware 912 "bootcount" is stored in the environment. To prevent a 913 saveenv on all reboots, the environment variable 914 "upgrade_available" is used. If "upgrade_available" is 915 0, "bootcount" is always 0, if "upgrade_available" is 916 1 "bootcount" is incremented in the environment. 917 So the Userspace Applikation must set the "upgrade_available" 918 and "bootcount" variable to 0, if a boot was successfully. 919 920- Pre-Boot Commands: 921 CONFIG_PREBOOT 922 923 When this option is #defined, the existence of the 924 environment variable "preboot" will be checked 925 immediately before starting the CONFIG_BOOTDELAY 926 countdown and/or running the auto-boot command resp. 927 entering interactive mode. 928 929 This feature is especially useful when "preboot" is 930 automatically generated or modified. For an example 931 see the LWMON board specific code: here "preboot" is 932 modified when the user holds down a certain 933 combination of keys on the (special) keyboard when 934 booting the systems 935 936- Serial Download Echo Mode: 937 CONFIG_LOADS_ECHO 938 If defined to 1, all characters received during a 939 serial download (using the "loads" command) are 940 echoed back. This might be needed by some terminal 941 emulations (like "cu"), but may as well just take 942 time on others. This setting #define's the initial 943 value of the "loads_echo" environment variable. 944 945- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 946 CONFIG_KGDB_BAUDRATE 947 Select one of the baudrates listed in 948 CONFIG_SYS_BAUDRATE_TABLE, see below. 949 950- Monitor Functions: 951 Monitor commands can be included or excluded 952 from the build by using the #include files 953 <config_cmd_all.h> and #undef'ing unwanted 954 commands, or using <config_cmd_default.h> 955 and augmenting with additional #define's 956 for wanted commands. 957 958 The default command configuration includes all commands 959 except those marked below with a "*". 960 961 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 962 CONFIG_CMD_ASKENV * ask for env variable 963 CONFIG_CMD_BDI bdinfo 964 CONFIG_CMD_BEDBUG * Include BedBug Debugger 965 CONFIG_CMD_BMP * BMP support 966 CONFIG_CMD_BSP * Board specific commands 967 CONFIG_CMD_BOOTD bootd 968 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 969 CONFIG_CMD_CACHE * icache, dcache 970 CONFIG_CMD_CLK * clock command support 971 CONFIG_CMD_CONSOLE coninfo 972 CONFIG_CMD_CRC32 * crc32 973 CONFIG_CMD_DATE * support for RTC, date/time... 974 CONFIG_CMD_DHCP * DHCP support 975 CONFIG_CMD_DIAG * Diagnostics 976 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 977 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 978 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 979 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 980 CONFIG_CMD_DTT * Digital Therm and Thermostat 981 CONFIG_CMD_ECHO echo arguments 982 CONFIG_CMD_EDITENV edit env variable 983 CONFIG_CMD_EEPROM * EEPROM read/write support 984 CONFIG_CMD_ELF * bootelf, bootvx 985 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 986 CONFIG_CMD_ENV_FLAGS * display details about env flags 987 CONFIG_CMD_ENV_EXISTS * check existence of env variable 988 CONFIG_CMD_EXPORTENV * export the environment 989 CONFIG_CMD_EXT2 * ext2 command support 990 CONFIG_CMD_EXT4 * ext4 command support 991 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 992 that work for multiple fs types 993 CONFIG_CMD_SAVEENV saveenv 994 CONFIG_CMD_FDC * Floppy Disk Support 995 CONFIG_CMD_FAT * FAT command support 996 CONFIG_CMD_FLASH flinfo, erase, protect 997 CONFIG_CMD_FPGA FPGA device initialization support 998 CONFIG_CMD_FUSE * Device fuse support 999 CONFIG_CMD_GETTIME * Get time since boot 1000 CONFIG_CMD_GO * the 'go' command (exec code) 1001 CONFIG_CMD_GREPENV * search environment 1002 CONFIG_CMD_HASH * calculate hash / digest 1003 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 1004 CONFIG_CMD_I2C * I2C serial bus support 1005 CONFIG_CMD_IDE * IDE harddisk support 1006 CONFIG_CMD_IMI iminfo 1007 CONFIG_CMD_IMLS List all images found in NOR flash 1008 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1009 CONFIG_CMD_IMMAP * IMMR dump support 1010 CONFIG_CMD_IOTRACE * I/O tracing for debugging 1011 CONFIG_CMD_IMPORTENV * import an environment 1012 CONFIG_CMD_INI * import data from an ini file into the env 1013 CONFIG_CMD_IRQ * irqinfo 1014 CONFIG_CMD_ITEST Integer/string test of 2 values 1015 CONFIG_CMD_JFFS2 * JFFS2 Support 1016 CONFIG_CMD_KGDB * kgdb 1017 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1018 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1019 (169.254.*.*) 1020 CONFIG_CMD_LOADB loadb 1021 CONFIG_CMD_LOADS loads 1022 CONFIG_CMD_MD5SUM * print md5 message digest 1023 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1024 CONFIG_CMD_MEMINFO * Display detailed memory information 1025 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1026 loop, loopw 1027 CONFIG_CMD_MEMTEST * mtest 1028 CONFIG_CMD_MISC Misc functions like sleep etc 1029 CONFIG_CMD_MMC * MMC memory mapped support 1030 CONFIG_CMD_MII * MII utility commands 1031 CONFIG_CMD_MTDPARTS * MTD partition support 1032 CONFIG_CMD_NAND * NAND support 1033 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1034 CONFIG_CMD_NFS NFS support 1035 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1036 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1037 CONFIG_CMD_PCI * pciinfo 1038 CONFIG_CMD_PCMCIA * PCMCIA support 1039 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1040 host 1041 CONFIG_CMD_PORTIO * Port I/O 1042 CONFIG_CMD_READ * Read raw data from partition 1043 CONFIG_CMD_REGINFO * Register dump 1044 CONFIG_CMD_RUN run command in env variable 1045 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1046 CONFIG_CMD_SAVES * save S record dump 1047 CONFIG_CMD_SCSI * SCSI Support 1048 CONFIG_CMD_SDRAM * print SDRAM configuration information 1049 (requires CONFIG_CMD_I2C) 1050 CONFIG_CMD_SETGETDCR Support for DCR Register access 1051 (4xx only) 1052 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1053 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1054 (requires CONFIG_CMD_MEMORY) 1055 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1056 CONFIG_CMD_SOURCE "source" command Support 1057 CONFIG_CMD_SPI * SPI serial bus support 1058 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1059 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1060 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1061 CONFIG_CMD_TIMER * access to the system tick timer 1062 CONFIG_CMD_USB * USB support 1063 CONFIG_CMD_CDP * Cisco Discover Protocol support 1064 CONFIG_CMD_MFSL * Microblaze FSL support 1065 CONFIG_CMD_XIMG Load part of Multi Image 1066 CONFIG_CMD_UUID * Generate random UUID or GUID string 1067 1068 EXAMPLE: If you want all functions except of network 1069 support you can write: 1070 1071 #include "config_cmd_all.h" 1072 #undef CONFIG_CMD_NET 1073 1074 Other Commands: 1075 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1076 1077 Note: Don't enable the "icache" and "dcache" commands 1078 (configuration option CONFIG_CMD_CACHE) unless you know 1079 what you (and your U-Boot users) are doing. Data 1080 cache cannot be enabled on systems like the 8xx or 1081 8260 (where accesses to the IMMR region must be 1082 uncached), and it cannot be disabled on all other 1083 systems where we (mis-) use the data cache to hold an 1084 initial stack and some data. 1085 1086 1087 XXX - this list needs to get updated! 1088 1089- Regular expression support: 1090 CONFIG_REGEX 1091 If this variable is defined, U-Boot is linked against 1092 the SLRE (Super Light Regular Expression) library, 1093 which adds regex support to some commands, as for 1094 example "env grep" and "setexpr". 1095 1096- Device tree: 1097 CONFIG_OF_CONTROL 1098 If this variable is defined, U-Boot will use a device tree 1099 to configure its devices, instead of relying on statically 1100 compiled #defines in the board file. This option is 1101 experimental and only available on a few boards. The device 1102 tree is available in the global data as gd->fdt_blob. 1103 1104 U-Boot needs to get its device tree from somewhere. This can 1105 be done using one of the two options below: 1106 1107 CONFIG_OF_EMBED 1108 If this variable is defined, U-Boot will embed a device tree 1109 binary in its image. This device tree file should be in the 1110 board directory and called <soc>-<board>.dts. The binary file 1111 is then picked up in board_init_f() and made available through 1112 the global data structure as gd->blob. 1113 1114 CONFIG_OF_SEPARATE 1115 If this variable is defined, U-Boot will build a device tree 1116 binary. It will be called u-boot.dtb. Architecture-specific 1117 code will locate it at run-time. Generally this works by: 1118 1119 cat u-boot.bin u-boot.dtb >image.bin 1120 1121 and in fact, U-Boot does this for you, creating a file called 1122 u-boot-dtb.bin which is useful in the common case. You can 1123 still use the individual files if you need something more 1124 exotic. 1125 1126- Watchdog: 1127 CONFIG_WATCHDOG 1128 If this variable is defined, it enables watchdog 1129 support for the SoC. There must be support in the SoC 1130 specific code for a watchdog. For the 8xx and 8260 1131 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1132 register. When supported for a specific SoC is 1133 available, then no further board specific code should 1134 be needed to use it. 1135 1136 CONFIG_HW_WATCHDOG 1137 When using a watchdog circuitry external to the used 1138 SoC, then define this variable and provide board 1139 specific code for the "hw_watchdog_reset" function. 1140 1141- U-Boot Version: 1142 CONFIG_VERSION_VARIABLE 1143 If this variable is defined, an environment variable 1144 named "ver" is created by U-Boot showing the U-Boot 1145 version as printed by the "version" command. 1146 Any change to this variable will be reverted at the 1147 next reset. 1148 1149- Real-Time Clock: 1150 1151 When CONFIG_CMD_DATE is selected, the type of the RTC 1152 has to be selected, too. Define exactly one of the 1153 following options: 1154 1155 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1156 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1157 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1158 CONFIG_RTC_MC146818 - use MC146818 RTC 1159 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1160 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1161 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1162 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1163 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1164 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1165 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1166 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1167 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1168 RV3029 RTC. 1169 1170 Note that if the RTC uses I2C, then the I2C interface 1171 must also be configured. See I2C Support, below. 1172 1173- GPIO Support: 1174 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1175 1176 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1177 chip-ngpio pairs that tell the PCA953X driver the number of 1178 pins supported by a particular chip. 1179 1180 Note that if the GPIO device uses I2C, then the I2C interface 1181 must also be configured. See I2C Support, below. 1182 1183- I/O tracing: 1184 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1185 accesses and can checksum them or write a list of them out 1186 to memory. See the 'iotrace' command for details. This is 1187 useful for testing device drivers since it can confirm that 1188 the driver behaves the same way before and after a code 1189 change. Currently this is supported on sandbox and arm. To 1190 add support for your architecture, add '#include <iotrace.h>' 1191 to the bottom of arch/<arch>/include/asm/io.h and test. 1192 1193 Example output from the 'iotrace stats' command is below. 1194 Note that if the trace buffer is exhausted, the checksum will 1195 still continue to operate. 1196 1197 iotrace is enabled 1198 Start: 10000000 (buffer start address) 1199 Size: 00010000 (buffer size) 1200 Offset: 00000120 (current buffer offset) 1201 Output: 10000120 (start + offset) 1202 Count: 00000018 (number of trace records) 1203 CRC32: 9526fb66 (CRC32 of all trace records) 1204 1205- Timestamp Support: 1206 1207 When CONFIG_TIMESTAMP is selected, the timestamp 1208 (date and time) of an image is printed by image 1209 commands like bootm or iminfo. This option is 1210 automatically enabled when you select CONFIG_CMD_DATE . 1211 1212- Partition Labels (disklabels) Supported: 1213 Zero or more of the following: 1214 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1215 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1216 Intel architecture, USB sticks, etc. 1217 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1218 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1219 bootloader. Note 2TB partition limit; see 1220 disk/part_efi.c 1221 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1222 1223 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1224 CONFIG_CMD_SCSI) you must configure support for at 1225 least one non-MTD partition type as well. 1226 1227- IDE Reset method: 1228 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1229 board configurations files but used nowhere! 1230 1231 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1232 be performed by calling the function 1233 ide_set_reset(int reset) 1234 which has to be defined in a board specific file 1235 1236- ATAPI Support: 1237 CONFIG_ATAPI 1238 1239 Set this to enable ATAPI support. 1240 1241- LBA48 Support 1242 CONFIG_LBA48 1243 1244 Set this to enable support for disks larger than 137GB 1245 Also look at CONFIG_SYS_64BIT_LBA. 1246 Whithout these , LBA48 support uses 32bit variables and will 'only' 1247 support disks up to 2.1TB. 1248 1249 CONFIG_SYS_64BIT_LBA: 1250 When enabled, makes the IDE subsystem use 64bit sector addresses. 1251 Default is 32bit. 1252 1253- SCSI Support: 1254 At the moment only there is only support for the 1255 SYM53C8XX SCSI controller; define 1256 CONFIG_SCSI_SYM53C8XX to enable it. 1257 1258 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1259 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1260 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1261 maximum numbers of LUNs, SCSI ID's and target 1262 devices. 1263 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1264 1265 The environment variable 'scsidevs' is set to the number of 1266 SCSI devices found during the last scan. 1267 1268- NETWORK Support (PCI): 1269 CONFIG_E1000 1270 Support for Intel 8254x/8257x gigabit chips. 1271 1272 CONFIG_E1000_SPI 1273 Utility code for direct access to the SPI bus on Intel 8257x. 1274 This does not do anything useful unless you set at least one 1275 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1276 1277 CONFIG_E1000_SPI_GENERIC 1278 Allow generic access to the SPI bus on the Intel 8257x, for 1279 example with the "sspi" command. 1280 1281 CONFIG_CMD_E1000 1282 Management command for E1000 devices. When used on devices 1283 with SPI support you can reprogram the EEPROM from U-Boot. 1284 1285 CONFIG_E1000_FALLBACK_MAC 1286 default MAC for empty EEPROM after production. 1287 1288 CONFIG_EEPRO100 1289 Support for Intel 82557/82559/82559ER chips. 1290 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1291 write routine for first time initialisation. 1292 1293 CONFIG_TULIP 1294 Support for Digital 2114x chips. 1295 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1296 modem chip initialisation (KS8761/QS6611). 1297 1298 CONFIG_NATSEMI 1299 Support for National dp83815 chips. 1300 1301 CONFIG_NS8382X 1302 Support for National dp8382[01] gigabit chips. 1303 1304- NETWORK Support (other): 1305 1306 CONFIG_DRIVER_AT91EMAC 1307 Support for AT91RM9200 EMAC. 1308 1309 CONFIG_RMII 1310 Define this to use reduced MII inteface 1311 1312 CONFIG_DRIVER_AT91EMAC_QUIET 1313 If this defined, the driver is quiet. 1314 The driver doen't show link status messages. 1315 1316 CONFIG_CALXEDA_XGMAC 1317 Support for the Calxeda XGMAC device 1318 1319 CONFIG_LAN91C96 1320 Support for SMSC's LAN91C96 chips. 1321 1322 CONFIG_LAN91C96_BASE 1323 Define this to hold the physical address 1324 of the LAN91C96's I/O space 1325 1326 CONFIG_LAN91C96_USE_32_BIT 1327 Define this to enable 32 bit addressing 1328 1329 CONFIG_SMC91111 1330 Support for SMSC's LAN91C111 chip 1331 1332 CONFIG_SMC91111_BASE 1333 Define this to hold the physical address 1334 of the device (I/O space) 1335 1336 CONFIG_SMC_USE_32_BIT 1337 Define this if data bus is 32 bits 1338 1339 CONFIG_SMC_USE_IOFUNCS 1340 Define this to use i/o functions instead of macros 1341 (some hardware wont work with macros) 1342 1343 CONFIG_DRIVER_TI_EMAC 1344 Support for davinci emac 1345 1346 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1347 Define this if you have more then 3 PHYs. 1348 1349 CONFIG_FTGMAC100 1350 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1351 1352 CONFIG_FTGMAC100_EGIGA 1353 Define this to use GE link update with gigabit PHY. 1354 Define this if FTGMAC100 is connected to gigabit PHY. 1355 If your system has 10/100 PHY only, it might not occur 1356 wrong behavior. Because PHY usually return timeout or 1357 useless data when polling gigabit status and gigabit 1358 control registers. This behavior won't affect the 1359 correctnessof 10/100 link speed update. 1360 1361 CONFIG_SMC911X 1362 Support for SMSC's LAN911x and LAN921x chips 1363 1364 CONFIG_SMC911X_BASE 1365 Define this to hold the physical address 1366 of the device (I/O space) 1367 1368 CONFIG_SMC911X_32_BIT 1369 Define this if data bus is 32 bits 1370 1371 CONFIG_SMC911X_16_BIT 1372 Define this if data bus is 16 bits. If your processor 1373 automatically converts one 32 bit word to two 16 bit 1374 words you may also try CONFIG_SMC911X_32_BIT. 1375 1376 CONFIG_SH_ETHER 1377 Support for Renesas on-chip Ethernet controller 1378 1379 CONFIG_SH_ETHER_USE_PORT 1380 Define the number of ports to be used 1381 1382 CONFIG_SH_ETHER_PHY_ADDR 1383 Define the ETH PHY's address 1384 1385 CONFIG_SH_ETHER_CACHE_WRITEBACK 1386 If this option is set, the driver enables cache flush. 1387 1388- PWM Support: 1389 CONFIG_PWM_IMX 1390 Support for PWM modul on the imx6. 1391 1392- TPM Support: 1393 CONFIG_TPM 1394 Support TPM devices. 1395 1396 CONFIG_TPM_TIS_I2C 1397 Support for i2c bus TPM devices. Only one device 1398 per system is supported at this time. 1399 1400 CONFIG_TPM_TIS_I2C_BUS_NUMBER 1401 Define the the i2c bus number for the TPM device 1402 1403 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS 1404 Define the TPM's address on the i2c bus 1405 1406 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1407 Define the burst count bytes upper limit 1408 1409 CONFIG_TPM_ATMEL_TWI 1410 Support for Atmel TWI TPM device. Requires I2C support. 1411 1412 CONFIG_TPM_TIS_LPC 1413 Support for generic parallel port TPM devices. Only one device 1414 per system is supported at this time. 1415 1416 CONFIG_TPM_TIS_BASE_ADDRESS 1417 Base address where the generic TPM device is mapped 1418 to. Contemporary x86 systems usually map it at 1419 0xfed40000. 1420 1421 CONFIG_CMD_TPM 1422 Add tpm monitor functions. 1423 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1424 provides monitor access to authorized functions. 1425 1426 CONFIG_TPM 1427 Define this to enable the TPM support library which provides 1428 functional interfaces to some TPM commands. 1429 Requires support for a TPM device. 1430 1431 CONFIG_TPM_AUTH_SESSIONS 1432 Define this to enable authorized functions in the TPM library. 1433 Requires CONFIG_TPM and CONFIG_SHA1. 1434 1435- USB Support: 1436 At the moment only the UHCI host controller is 1437 supported (PIP405, MIP405, MPC5200); define 1438 CONFIG_USB_UHCI to enable it. 1439 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1440 and define CONFIG_USB_STORAGE to enable the USB 1441 storage devices. 1442 Note: 1443 Supported are USB Keyboards and USB Floppy drives 1444 (TEAC FD-05PUB). 1445 MPC5200 USB requires additional defines: 1446 CONFIG_USB_CLOCK 1447 for 528 MHz Clock: 0x0001bbbb 1448 CONFIG_PSC3_USB 1449 for USB on PSC3 1450 CONFIG_USB_CONFIG 1451 for differential drivers: 0x00001000 1452 for single ended drivers: 0x00005000 1453 for differential drivers on PSC3: 0x00000100 1454 for single ended drivers on PSC3: 0x00004100 1455 CONFIG_SYS_USB_EVENT_POLL 1456 May be defined to allow interrupt polling 1457 instead of using asynchronous interrupts 1458 1459 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1460 txfilltuning field in the EHCI controller on reset. 1461 1462- USB Device: 1463 Define the below if you wish to use the USB console. 1464 Once firmware is rebuilt from a serial console issue the 1465 command "setenv stdin usbtty; setenv stdout usbtty" and 1466 attach your USB cable. The Unix command "dmesg" should print 1467 it has found a new device. The environment variable usbtty 1468 can be set to gserial or cdc_acm to enable your device to 1469 appear to a USB host as a Linux gserial device or a 1470 Common Device Class Abstract Control Model serial device. 1471 If you select usbtty = gserial you should be able to enumerate 1472 a Linux host by 1473 # modprobe usbserial vendor=0xVendorID product=0xProductID 1474 else if using cdc_acm, simply setting the environment 1475 variable usbtty to be cdc_acm should suffice. The following 1476 might be defined in YourBoardName.h 1477 1478 CONFIG_USB_DEVICE 1479 Define this to build a UDC device 1480 1481 CONFIG_USB_TTY 1482 Define this to have a tty type of device available to 1483 talk to the UDC device 1484 1485 CONFIG_USBD_HS 1486 Define this to enable the high speed support for usb 1487 device and usbtty. If this feature is enabled, a routine 1488 int is_usbd_high_speed(void) 1489 also needs to be defined by the driver to dynamically poll 1490 whether the enumeration has succeded at high speed or full 1491 speed. 1492 1493 CONFIG_SYS_CONSOLE_IS_IN_ENV 1494 Define this if you want stdin, stdout &/or stderr to 1495 be set to usbtty. 1496 1497 mpc8xx: 1498 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1499 Derive USB clock from external clock "blah" 1500 - CONFIG_SYS_USB_EXTC_CLK 0x02 1501 1502 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1503 Derive USB clock from brgclk 1504 - CONFIG_SYS_USB_BRG_CLK 0x04 1505 1506 If you have a USB-IF assigned VendorID then you may wish to 1507 define your own vendor specific values either in BoardName.h 1508 or directly in usbd_vendor_info.h. If you don't define 1509 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1510 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1511 should pretend to be a Linux device to it's target host. 1512 1513 CONFIG_USBD_MANUFACTURER 1514 Define this string as the name of your company for 1515 - CONFIG_USBD_MANUFACTURER "my company" 1516 1517 CONFIG_USBD_PRODUCT_NAME 1518 Define this string as the name of your product 1519 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1520 1521 CONFIG_USBD_VENDORID 1522 Define this as your assigned Vendor ID from the USB 1523 Implementors Forum. This *must* be a genuine Vendor ID 1524 to avoid polluting the USB namespace. 1525 - CONFIG_USBD_VENDORID 0xFFFF 1526 1527 CONFIG_USBD_PRODUCTID 1528 Define this as the unique Product ID 1529 for your device 1530 - CONFIG_USBD_PRODUCTID 0xFFFF 1531 1532- ULPI Layer Support: 1533 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1534 the generic ULPI layer. The generic layer accesses the ULPI PHY 1535 via the platform viewport, so you need both the genric layer and 1536 the viewport enabled. Currently only Chipidea/ARC based 1537 viewport is supported. 1538 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1539 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1540 If your ULPI phy needs a different reference clock than the 1541 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1542 the appropriate value in Hz. 1543 1544- MMC Support: 1545 The MMC controller on the Intel PXA is supported. To 1546 enable this define CONFIG_MMC. The MMC can be 1547 accessed from the boot prompt by mapping the device 1548 to physical memory similar to flash. Command line is 1549 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1550 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1551 1552 CONFIG_SH_MMCIF 1553 Support for Renesas on-chip MMCIF controller 1554 1555 CONFIG_SH_MMCIF_ADDR 1556 Define the base address of MMCIF registers 1557 1558 CONFIG_SH_MMCIF_CLK 1559 Define the clock frequency for MMCIF 1560 1561 CONFIG_GENERIC_MMC 1562 Enable the generic MMC driver 1563 1564 CONFIG_SUPPORT_EMMC_BOOT 1565 Enable some additional features of the eMMC boot partitions. 1566 1567 CONFIG_SUPPORT_EMMC_RPMB 1568 Enable the commands for reading, writing and programming the 1569 key for the Replay Protection Memory Block partition in eMMC. 1570 1571- USB Device Firmware Update (DFU) class support: 1572 CONFIG_DFU_FUNCTION 1573 This enables the USB portion of the DFU USB class 1574 1575 CONFIG_CMD_DFU 1576 This enables the command "dfu" which is used to have 1577 U-Boot create a DFU class device via USB. This command 1578 requires that the "dfu_alt_info" environment variable be 1579 set and define the alt settings to expose to the host. 1580 1581 CONFIG_DFU_MMC 1582 This enables support for exposing (e)MMC devices via DFU. 1583 1584 CONFIG_DFU_NAND 1585 This enables support for exposing NAND devices via DFU. 1586 1587 CONFIG_DFU_RAM 1588 This enables support for exposing RAM via DFU. 1589 Note: DFU spec refer to non-volatile memory usage, but 1590 allow usages beyond the scope of spec - here RAM usage, 1591 one that would help mostly the developer. 1592 1593 CONFIG_SYS_DFU_DATA_BUF_SIZE 1594 Dfu transfer uses a buffer before writing data to the 1595 raw storage device. Make the size (in bytes) of this buffer 1596 configurable. The size of this buffer is also configurable 1597 through the "dfu_bufsiz" environment variable. 1598 1599 CONFIG_SYS_DFU_MAX_FILE_SIZE 1600 When updating files rather than the raw storage device, 1601 we use a static buffer to copy the file into and then write 1602 the buffer once we've been given the whole file. Define 1603 this to the maximum filesize (in bytes) for the buffer. 1604 Default is 4 MiB if undefined. 1605 1606 DFU_DEFAULT_POLL_TIMEOUT 1607 Poll timeout [ms], is the timeout a device can send to the 1608 host. The host must wait for this timeout before sending 1609 a subsequent DFU_GET_STATUS request to the device. 1610 1611 DFU_MANIFEST_POLL_TIMEOUT 1612 Poll timeout [ms], which the device sends to the host when 1613 entering dfuMANIFEST state. Host waits this timeout, before 1614 sending again an USB request to the device. 1615 1616- USB Device Android Fastboot support: 1617 CONFIG_CMD_FASTBOOT 1618 This enables the command "fastboot" which enables the Android 1619 fastboot mode for the platform's USB device. Fastboot is a USB 1620 protocol for downloading images, flashing and device control 1621 used on Android devices. 1622 See doc/README.android-fastboot for more information. 1623 1624 CONFIG_ANDROID_BOOT_IMAGE 1625 This enables support for booting images which use the Android 1626 image format header. 1627 1628 CONFIG_USB_FASTBOOT_BUF_ADDR 1629 The fastboot protocol requires a large memory buffer for 1630 downloads. Define this to the starting RAM address to use for 1631 downloaded images. 1632 1633 CONFIG_USB_FASTBOOT_BUF_SIZE 1634 The fastboot protocol requires a large memory buffer for 1635 downloads. This buffer should be as large as possible for a 1636 platform. Define this to the size available RAM for fastboot. 1637 1638 CONFIG_FASTBOOT_FLASH 1639 The fastboot protocol includes a "flash" command for writing 1640 the downloaded image to a non-volatile storage device. Define 1641 this to enable the "fastboot flash" command. 1642 1643 CONFIG_FASTBOOT_FLASH_MMC_DEV 1644 The fastboot "flash" command requires additional information 1645 regarding the non-volatile storage device. Define this to 1646 the eMMC device that fastboot should use to store the image. 1647 1648- Journaling Flash filesystem support: 1649 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1650 CONFIG_JFFS2_NAND_DEV 1651 Define these for a default partition on a NAND device 1652 1653 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1654 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1655 Define these for a default partition on a NOR device 1656 1657 CONFIG_SYS_JFFS_CUSTOM_PART 1658 Define this to create an own partition. You have to provide a 1659 function struct part_info* jffs2_part_info(int part_num) 1660 1661 If you define only one JFFS2 partition you may also want to 1662 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1663 to disable the command chpart. This is the default when you 1664 have not defined a custom partition 1665 1666- FAT(File Allocation Table) filesystem write function support: 1667 CONFIG_FAT_WRITE 1668 1669 Define this to enable support for saving memory data as a 1670 file in FAT formatted partition. 1671 1672 This will also enable the command "fatwrite" enabling the 1673 user to write files to FAT. 1674 1675CBFS (Coreboot Filesystem) support 1676 CONFIG_CMD_CBFS 1677 1678 Define this to enable support for reading from a Coreboot 1679 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1680 and cbfsload. 1681 1682- FAT(File Allocation Table) filesystem cluster size: 1683 CONFIG_FS_FAT_MAX_CLUSTSIZE 1684 1685 Define the max cluster size for fat operations else 1686 a default value of 65536 will be defined. 1687 1688- Keyboard Support: 1689 CONFIG_ISA_KEYBOARD 1690 1691 Define this to enable standard (PC-Style) keyboard 1692 support 1693 1694 CONFIG_I8042_KBD 1695 Standard PC keyboard driver with US (is default) and 1696 GERMAN key layout (switch via environment 'keymap=de') support. 1697 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1698 for cfb_console. Supports cursor blinking. 1699 1700 CONFIG_CROS_EC_KEYB 1701 Enables a Chrome OS keyboard using the CROS_EC interface. 1702 This uses CROS_EC to communicate with a second microcontroller 1703 which provides key scans on request. 1704 1705- Video support: 1706 CONFIG_VIDEO 1707 1708 Define this to enable video support (for output to 1709 video). 1710 1711 CONFIG_VIDEO_CT69000 1712 1713 Enable Chips & Technologies 69000 Video chip 1714 1715 CONFIG_VIDEO_SMI_LYNXEM 1716 Enable Silicon Motion SMI 712/710/810 Video chip. The 1717 video output is selected via environment 'videoout' 1718 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1719 assumed. 1720 1721 For the CT69000 and SMI_LYNXEM drivers, videomode is 1722 selected via environment 'videomode'. Two different ways 1723 are possible: 1724 - "videomode=num" 'num' is a standard LiLo mode numbers. 1725 Following standard modes are supported (* is default): 1726 1727 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1728 -------------+--------------------------------------------- 1729 8 bits | 0x301* 0x303 0x305 0x161 0x307 1730 15 bits | 0x310 0x313 0x316 0x162 0x319 1731 16 bits | 0x311 0x314 0x317 0x163 0x31A 1732 24 bits | 0x312 0x315 0x318 ? 0x31B 1733 -------------+--------------------------------------------- 1734 (i.e. setenv videomode 317; saveenv; reset;) 1735 1736 - "videomode=bootargs" all the video parameters are parsed 1737 from the bootargs. (See drivers/video/videomodes.c) 1738 1739 1740 CONFIG_VIDEO_SED13806 1741 Enable Epson SED13806 driver. This driver supports 8bpp 1742 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1743 or CONFIG_VIDEO_SED13806_16BPP 1744 1745 CONFIG_FSL_DIU_FB 1746 Enable the Freescale DIU video driver. Reference boards for 1747 SOCs that have a DIU should define this macro to enable DIU 1748 support, and should also define these other macros: 1749 1750 CONFIG_SYS_DIU_ADDR 1751 CONFIG_VIDEO 1752 CONFIG_CMD_BMP 1753 CONFIG_CFB_CONSOLE 1754 CONFIG_VIDEO_SW_CURSOR 1755 CONFIG_VGA_AS_SINGLE_DEVICE 1756 CONFIG_VIDEO_LOGO 1757 CONFIG_VIDEO_BMP_LOGO 1758 1759 The DIU driver will look for the 'video-mode' environment 1760 variable, and if defined, enable the DIU as a console during 1761 boot. See the documentation file README.video for a 1762 description of this variable. 1763 1764 CONFIG_VIDEO_VGA 1765 1766 Enable the VGA video / BIOS for x86. The alternative if you 1767 are using coreboot is to use the coreboot frame buffer 1768 driver. 1769 1770 1771- Keyboard Support: 1772 CONFIG_KEYBOARD 1773 1774 Define this to enable a custom keyboard support. 1775 This simply calls drv_keyboard_init() which must be 1776 defined in your board-specific files. 1777 The only board using this so far is RBC823. 1778 1779- LCD Support: CONFIG_LCD 1780 1781 Define this to enable LCD support (for output to LCD 1782 display); also select one of the supported displays 1783 by defining one of these: 1784 1785 CONFIG_ATMEL_LCD: 1786 1787 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1788 1789 CONFIG_NEC_NL6448AC33: 1790 1791 NEC NL6448AC33-18. Active, color, single scan. 1792 1793 CONFIG_NEC_NL6448BC20 1794 1795 NEC NL6448BC20-08. 6.5", 640x480. 1796 Active, color, single scan. 1797 1798 CONFIG_NEC_NL6448BC33_54 1799 1800 NEC NL6448BC33-54. 10.4", 640x480. 1801 Active, color, single scan. 1802 1803 CONFIG_SHARP_16x9 1804 1805 Sharp 320x240. Active, color, single scan. 1806 It isn't 16x9, and I am not sure what it is. 1807 1808 CONFIG_SHARP_LQ64D341 1809 1810 Sharp LQ64D341 display, 640x480. 1811 Active, color, single scan. 1812 1813 CONFIG_HLD1045 1814 1815 HLD1045 display, 640x480. 1816 Active, color, single scan. 1817 1818 CONFIG_OPTREX_BW 1819 1820 Optrex CBL50840-2 NF-FW 99 22 M5 1821 or 1822 Hitachi LMG6912RPFC-00T 1823 or 1824 Hitachi SP14Q002 1825 1826 320x240. Black & white. 1827 1828 Normally display is black on white background; define 1829 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1830 1831 CONFIG_LCD_ALIGNMENT 1832 1833 Normally the LCD is page-aligned (tyically 4KB). If this is 1834 defined then the LCD will be aligned to this value instead. 1835 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1836 here, since it is cheaper to change data cache settings on 1837 a per-section basis. 1838 1839 CONFIG_CONSOLE_SCROLL_LINES 1840 1841 When the console need to be scrolled, this is the number of 1842 lines to scroll by. It defaults to 1. Increasing this makes 1843 the console jump but can help speed up operation when scrolling 1844 is slow. 1845 1846 CONFIG_LCD_BMP_RLE8 1847 1848 Support drawing of RLE8-compressed bitmaps on the LCD. 1849 1850 CONFIG_I2C_EDID 1851 1852 Enables an 'i2c edid' command which can read EDID 1853 information over I2C from an attached LCD display. 1854 1855- Splash Screen Support: CONFIG_SPLASH_SCREEN 1856 1857 If this option is set, the environment is checked for 1858 a variable "splashimage". If found, the usual display 1859 of logo, copyright and system information on the LCD 1860 is suppressed and the BMP image at the address 1861 specified in "splashimage" is loaded instead. The 1862 console is redirected to the "nulldev", too. This 1863 allows for a "silent" boot where a splash screen is 1864 loaded very quickly after power-on. 1865 1866 CONFIG_SPLASHIMAGE_GUARD 1867 1868 If this option is set, then U-Boot will prevent the environment 1869 variable "splashimage" from being set to a problematic address 1870 (see README.displaying-bmps). 1871 This option is useful for targets where, due to alignment 1872 restrictions, an improperly aligned BMP image will cause a data 1873 abort. If you think you will not have problems with unaligned 1874 accesses (for example because your toolchain prevents them) 1875 there is no need to set this option. 1876 1877 CONFIG_SPLASH_SCREEN_ALIGN 1878 1879 If this option is set the splash image can be freely positioned 1880 on the screen. Environment variable "splashpos" specifies the 1881 position as "x,y". If a positive number is given it is used as 1882 number of pixel from left/top. If a negative number is given it 1883 is used as number of pixel from right/bottom. You can also 1884 specify 'm' for centering the image. 1885 1886 Example: 1887 setenv splashpos m,m 1888 => image at center of screen 1889 1890 setenv splashpos 30,20 1891 => image at x = 30 and y = 20 1892 1893 setenv splashpos -10,m 1894 => vertically centered image 1895 at x = dspWidth - bmpWidth - 9 1896 1897- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1898 1899 If this option is set, additionally to standard BMP 1900 images, gzipped BMP images can be displayed via the 1901 splashscreen support or the bmp command. 1902 1903- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1904 1905 If this option is set, 8-bit RLE compressed BMP images 1906 can be displayed via the splashscreen support or the 1907 bmp command. 1908 1909- Do compresssing for memory range: 1910 CONFIG_CMD_ZIP 1911 1912 If this option is set, it would use zlib deflate method 1913 to compress the specified memory at its best effort. 1914 1915- Compression support: 1916 CONFIG_GZIP 1917 1918 Enabled by default to support gzip compressed images. 1919 1920 CONFIG_BZIP2 1921 1922 If this option is set, support for bzip2 compressed 1923 images is included. If not, only uncompressed and gzip 1924 compressed images are supported. 1925 1926 NOTE: the bzip2 algorithm requires a lot of RAM, so 1927 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1928 be at least 4MB. 1929 1930 CONFIG_LZMA 1931 1932 If this option is set, support for lzma compressed 1933 images is included. 1934 1935 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1936 requires an amount of dynamic memory that is given by the 1937 formula: 1938 1939 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1940 1941 Where lc and lp stand for, respectively, Literal context bits 1942 and Literal pos bits. 1943 1944 This value is upper-bounded by 14MB in the worst case. Anyway, 1945 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1946 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1947 a very small buffer. 1948 1949 Use the lzmainfo tool to determinate the lc and lp values and 1950 then calculate the amount of needed dynamic memory (ensuring 1951 the appropriate CONFIG_SYS_MALLOC_LEN value). 1952 1953 CONFIG_LZO 1954 1955 If this option is set, support for LZO compressed images 1956 is included. 1957 1958- MII/PHY support: 1959 CONFIG_PHY_ADDR 1960 1961 The address of PHY on MII bus. 1962 1963 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1964 1965 The clock frequency of the MII bus 1966 1967 CONFIG_PHY_GIGE 1968 1969 If this option is set, support for speed/duplex 1970 detection of gigabit PHY is included. 1971 1972 CONFIG_PHY_RESET_DELAY 1973 1974 Some PHY like Intel LXT971A need extra delay after 1975 reset before any MII register access is possible. 1976 For such PHY, set this option to the usec delay 1977 required. (minimum 300usec for LXT971A) 1978 1979 CONFIG_PHY_CMD_DELAY (ppc4xx) 1980 1981 Some PHY like Intel LXT971A need extra delay after 1982 command issued before MII status register can be read 1983 1984- Ethernet address: 1985 CONFIG_ETHADDR 1986 CONFIG_ETH1ADDR 1987 CONFIG_ETH2ADDR 1988 CONFIG_ETH3ADDR 1989 CONFIG_ETH4ADDR 1990 CONFIG_ETH5ADDR 1991 1992 Define a default value for Ethernet address to use 1993 for the respective Ethernet interface, in case this 1994 is not determined automatically. 1995 1996- IP address: 1997 CONFIG_IPADDR 1998 1999 Define a default value for the IP address to use for 2000 the default Ethernet interface, in case this is not 2001 determined through e.g. bootp. 2002 (Environment variable "ipaddr") 2003 2004- Server IP address: 2005 CONFIG_SERVERIP 2006 2007 Defines a default value for the IP address of a TFTP 2008 server to contact when using the "tftboot" command. 2009 (Environment variable "serverip") 2010 2011 CONFIG_KEEP_SERVERADDR 2012 2013 Keeps the server's MAC address, in the env 'serveraddr' 2014 for passing to bootargs (like Linux's netconsole option) 2015 2016- Gateway IP address: 2017 CONFIG_GATEWAYIP 2018 2019 Defines a default value for the IP address of the 2020 default router where packets to other networks are 2021 sent to. 2022 (Environment variable "gatewayip") 2023 2024- Subnet mask: 2025 CONFIG_NETMASK 2026 2027 Defines a default value for the subnet mask (or 2028 routing prefix) which is used to determine if an IP 2029 address belongs to the local subnet or needs to be 2030 forwarded through a router. 2031 (Environment variable "netmask") 2032 2033- Multicast TFTP Mode: 2034 CONFIG_MCAST_TFTP 2035 2036 Defines whether you want to support multicast TFTP as per 2037 rfc-2090; for example to work with atftp. Lets lots of targets 2038 tftp down the same boot image concurrently. Note: the Ethernet 2039 driver in use must provide a function: mcast() to join/leave a 2040 multicast group. 2041 2042- BOOTP Recovery Mode: 2043 CONFIG_BOOTP_RANDOM_DELAY 2044 2045 If you have many targets in a network that try to 2046 boot using BOOTP, you may want to avoid that all 2047 systems send out BOOTP requests at precisely the same 2048 moment (which would happen for instance at recovery 2049 from a power failure, when all systems will try to 2050 boot, thus flooding the BOOTP server. Defining 2051 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 2052 inserted before sending out BOOTP requests. The 2053 following delays are inserted then: 2054 2055 1st BOOTP request: delay 0 ... 1 sec 2056 2nd BOOTP request: delay 0 ... 2 sec 2057 3rd BOOTP request: delay 0 ... 4 sec 2058 4th and following 2059 BOOTP requests: delay 0 ... 8 sec 2060 2061 CONFIG_BOOTP_ID_CACHE_SIZE 2062 2063 BOOTP packets are uniquely identified using a 32-bit ID. The 2064 server will copy the ID from client requests to responses and 2065 U-Boot will use this to determine if it is the destination of 2066 an incoming response. Some servers will check that addresses 2067 aren't in use before handing them out (usually using an ARP 2068 ping) and therefore take up to a few hundred milliseconds to 2069 respond. Network congestion may also influence the time it 2070 takes for a response to make it back to the client. If that 2071 time is too long, U-Boot will retransmit requests. In order 2072 to allow earlier responses to still be accepted after these 2073 retransmissions, U-Boot's BOOTP client keeps a small cache of 2074 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 2075 cache. The default is to keep IDs for up to four outstanding 2076 requests. Increasing this will allow U-Boot to accept offers 2077 from a BOOTP client in networks with unusually high latency. 2078 2079- DHCP Advanced Options: 2080 You can fine tune the DHCP functionality by defining 2081 CONFIG_BOOTP_* symbols: 2082 2083 CONFIG_BOOTP_SUBNETMASK 2084 CONFIG_BOOTP_GATEWAY 2085 CONFIG_BOOTP_HOSTNAME 2086 CONFIG_BOOTP_NISDOMAIN 2087 CONFIG_BOOTP_BOOTPATH 2088 CONFIG_BOOTP_BOOTFILESIZE 2089 CONFIG_BOOTP_DNS 2090 CONFIG_BOOTP_DNS2 2091 CONFIG_BOOTP_SEND_HOSTNAME 2092 CONFIG_BOOTP_NTPSERVER 2093 CONFIG_BOOTP_TIMEOFFSET 2094 CONFIG_BOOTP_VENDOREX 2095 CONFIG_BOOTP_MAY_FAIL 2096 2097 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2098 environment variable, not the BOOTP server. 2099 2100 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2101 after the configured retry count, the call will fail 2102 instead of starting over. This can be used to fail over 2103 to Link-local IP address configuration if the DHCP server 2104 is not available. 2105 2106 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2107 serverip from a DHCP server, it is possible that more 2108 than one DNS serverip is offered to the client. 2109 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2110 serverip will be stored in the additional environment 2111 variable "dnsip2". The first DNS serverip is always 2112 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2113 is defined. 2114 2115 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2116 to do a dynamic update of a DNS server. To do this, they 2117 need the hostname of the DHCP requester. 2118 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2119 of the "hostname" environment variable is passed as 2120 option 12 to the DHCP server. 2121 2122 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2123 2124 A 32bit value in microseconds for a delay between 2125 receiving a "DHCP Offer" and sending the "DHCP Request". 2126 This fixes a problem with certain DHCP servers that don't 2127 respond 100% of the time to a "DHCP request". E.g. On an 2128 AT91RM9200 processor running at 180MHz, this delay needed 2129 to be *at least* 15,000 usec before a Windows Server 2003 2130 DHCP server would reply 100% of the time. I recommend at 2131 least 50,000 usec to be safe. The alternative is to hope 2132 that one of the retries will be successful but note that 2133 the DHCP timeout and retry process takes a longer than 2134 this delay. 2135 2136 - Link-local IP address negotiation: 2137 Negotiate with other link-local clients on the local network 2138 for an address that doesn't require explicit configuration. 2139 This is especially useful if a DHCP server cannot be guaranteed 2140 to exist in all environments that the device must operate. 2141 2142 See doc/README.link-local for more information. 2143 2144 - CDP Options: 2145 CONFIG_CDP_DEVICE_ID 2146 2147 The device id used in CDP trigger frames. 2148 2149 CONFIG_CDP_DEVICE_ID_PREFIX 2150 2151 A two character string which is prefixed to the MAC address 2152 of the device. 2153 2154 CONFIG_CDP_PORT_ID 2155 2156 A printf format string which contains the ascii name of 2157 the port. Normally is set to "eth%d" which sets 2158 eth0 for the first Ethernet, eth1 for the second etc. 2159 2160 CONFIG_CDP_CAPABILITIES 2161 2162 A 32bit integer which indicates the device capabilities; 2163 0x00000010 for a normal host which does not forwards. 2164 2165 CONFIG_CDP_VERSION 2166 2167 An ascii string containing the version of the software. 2168 2169 CONFIG_CDP_PLATFORM 2170 2171 An ascii string containing the name of the platform. 2172 2173 CONFIG_CDP_TRIGGER 2174 2175 A 32bit integer sent on the trigger. 2176 2177 CONFIG_CDP_POWER_CONSUMPTION 2178 2179 A 16bit integer containing the power consumption of the 2180 device in .1 of milliwatts. 2181 2182 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2183 2184 A byte containing the id of the VLAN. 2185 2186- Status LED: CONFIG_STATUS_LED 2187 2188 Several configurations allow to display the current 2189 status using a LED. For instance, the LED will blink 2190 fast while running U-Boot code, stop blinking as 2191 soon as a reply to a BOOTP request was received, and 2192 start blinking slow once the Linux kernel is running 2193 (supported by a status LED driver in the Linux 2194 kernel). Defining CONFIG_STATUS_LED enables this 2195 feature in U-Boot. 2196 2197 Additional options: 2198 2199 CONFIG_GPIO_LED 2200 The status LED can be connected to a GPIO pin. 2201 In such cases, the gpio_led driver can be used as a 2202 status LED backend implementation. Define CONFIG_GPIO_LED 2203 to include the gpio_led driver in the U-Boot binary. 2204 2205 CONFIG_GPIO_LED_INVERTED_TABLE 2206 Some GPIO connected LEDs may have inverted polarity in which 2207 case the GPIO high value corresponds to LED off state and 2208 GPIO low value corresponds to LED on state. 2209 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2210 with a list of GPIO LEDs that have inverted polarity. 2211 2212- CAN Support: CONFIG_CAN_DRIVER 2213 2214 Defining CONFIG_CAN_DRIVER enables CAN driver support 2215 on those systems that support this (optional) 2216 feature, like the TQM8xxL modules. 2217 2218- I2C Support: CONFIG_SYS_I2C 2219 2220 This enable the NEW i2c subsystem, and will allow you to use 2221 i2c commands at the u-boot command line (as long as you set 2222 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2223 based realtime clock chips or other i2c devices. See 2224 common/cmd_i2c.c for a description of the command line 2225 interface. 2226 2227 ported i2c driver to the new framework: 2228 - drivers/i2c/soft_i2c.c: 2229 - activate first bus with CONFIG_SYS_I2C_SOFT define 2230 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2231 for defining speed and slave address 2232 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2233 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2234 for defining speed and slave address 2235 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2236 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2237 for defining speed and slave address 2238 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2239 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2240 for defining speed and slave address 2241 2242 - drivers/i2c/fsl_i2c.c: 2243 - activate i2c driver with CONFIG_SYS_I2C_FSL 2244 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2245 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2246 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2247 bus. 2248 - If your board supports a second fsl i2c bus, define 2249 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2250 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2251 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2252 second bus. 2253 2254 - drivers/i2c/tegra_i2c.c: 2255 - activate this driver with CONFIG_SYS_I2C_TEGRA 2256 - This driver adds 4 i2c buses with a fix speed from 2257 100000 and the slave addr 0! 2258 2259 - drivers/i2c/ppc4xx_i2c.c 2260 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2261 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2262 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2263 2264 - drivers/i2c/i2c_mxc.c 2265 - activate this driver with CONFIG_SYS_I2C_MXC 2266 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2267 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2268 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2269 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2270 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2271 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2272 If thoses defines are not set, default value is 100000 2273 for speed, and 0 for slave. 2274 2275 - drivers/i2c/rcar_i2c.c: 2276 - activate this driver with CONFIG_SYS_I2C_RCAR 2277 - This driver adds 4 i2c buses 2278 2279 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2280 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2281 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2282 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2283 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2284 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2285 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2286 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2287 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2288 2289 - drivers/i2c/sh_i2c.c: 2290 - activate this driver with CONFIG_SYS_I2C_SH 2291 - This driver adds from 2 to 5 i2c buses 2292 2293 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2294 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2295 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2296 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2297 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2298 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2299 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2300 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2301 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2302 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2303 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2304 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2305 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses 2306 2307 - drivers/i2c/omap24xx_i2c.c 2308 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2309 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2310 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2311 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2312 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2313 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2314 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2315 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2316 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2317 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2318 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2319 2320 - drivers/i2c/zynq_i2c.c 2321 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2322 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2323 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2324 2325 - drivers/i2c/s3c24x0_i2c.c: 2326 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2327 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2328 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2329 with a fix speed from 100000 and the slave addr 0! 2330 2331 - drivers/i2c/ihs_i2c.c 2332 - activate this driver with CONFIG_SYS_I2C_IHS 2333 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2334 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2335 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2336 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2337 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2338 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2339 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2340 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2341 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2342 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2343 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2344 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2345 2346 additional defines: 2347 2348 CONFIG_SYS_NUM_I2C_BUSES 2349 Hold the number of i2c busses you want to use. If you 2350 don't use/have i2c muxes on your i2c bus, this 2351 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2352 omit this define. 2353 2354 CONFIG_SYS_I2C_DIRECT_BUS 2355 define this, if you don't use i2c muxes on your hardware. 2356 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2357 omit this define. 2358 2359 CONFIG_SYS_I2C_MAX_HOPS 2360 define how many muxes are maximal consecutively connected 2361 on one i2c bus. If you not use i2c muxes, omit this 2362 define. 2363 2364 CONFIG_SYS_I2C_BUSES 2365 hold a list of busses you want to use, only used if 2366 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2367 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2368 CONFIG_SYS_NUM_I2C_BUSES = 9: 2369 2370 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2371 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2372 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2373 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2374 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2375 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2376 {1, {I2C_NULL_HOP}}, \ 2377 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2378 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2379 } 2380 2381 which defines 2382 bus 0 on adapter 0 without a mux 2383 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2384 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2385 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2386 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2387 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2388 bus 6 on adapter 1 without a mux 2389 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2390 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2391 2392 If you do not have i2c muxes on your board, omit this define. 2393 2394- Legacy I2C Support: CONFIG_HARD_I2C 2395 2396 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2397 provides the following compelling advantages: 2398 2399 - more than one i2c adapter is usable 2400 - approved multibus support 2401 - better i2c mux support 2402 2403 ** Please consider updating your I2C driver now. ** 2404 2405 These enable legacy I2C serial bus commands. Defining 2406 CONFIG_HARD_I2C will include the appropriate I2C driver 2407 for the selected CPU. 2408 2409 This will allow you to use i2c commands at the u-boot 2410 command line (as long as you set CONFIG_CMD_I2C in 2411 CONFIG_COMMANDS) and communicate with i2c based realtime 2412 clock chips. See common/cmd_i2c.c for a description of the 2413 command line interface. 2414 2415 CONFIG_HARD_I2C selects a hardware I2C controller. 2416 2417 There are several other quantities that must also be 2418 defined when you define CONFIG_HARD_I2C. 2419 2420 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2421 to be the frequency (in Hz) at which you wish your i2c bus 2422 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2423 the CPU's i2c node address). 2424 2425 Now, the u-boot i2c code for the mpc8xx 2426 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2427 and so its address should therefore be cleared to 0 (See, 2428 eg, MPC823e User's Manual p.16-473). So, set 2429 CONFIG_SYS_I2C_SLAVE to 0. 2430 2431 CONFIG_SYS_I2C_INIT_MPC5XXX 2432 2433 When a board is reset during an i2c bus transfer 2434 chips might think that the current transfer is still 2435 in progress. Reset the slave devices by sending start 2436 commands until the slave device responds. 2437 2438 That's all that's required for CONFIG_HARD_I2C. 2439 2440 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2441 then the following macros need to be defined (examples are 2442 from include/configs/lwmon.h): 2443 2444 I2C_INIT 2445 2446 (Optional). Any commands necessary to enable the I2C 2447 controller or configure ports. 2448 2449 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2450 2451 I2C_PORT 2452 2453 (Only for MPC8260 CPU). The I/O port to use (the code 2454 assumes both bits are on the same port). Valid values 2455 are 0..3 for ports A..D. 2456 2457 I2C_ACTIVE 2458 2459 The code necessary to make the I2C data line active 2460 (driven). If the data line is open collector, this 2461 define can be null. 2462 2463 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2464 2465 I2C_TRISTATE 2466 2467 The code necessary to make the I2C data line tri-stated 2468 (inactive). If the data line is open collector, this 2469 define can be null. 2470 2471 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2472 2473 I2C_READ 2474 2475 Code that returns true if the I2C data line is high, 2476 false if it is low. 2477 2478 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2479 2480 I2C_SDA(bit) 2481 2482 If <bit> is true, sets the I2C data line high. If it 2483 is false, it clears it (low). 2484 2485 eg: #define I2C_SDA(bit) \ 2486 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2487 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2488 2489 I2C_SCL(bit) 2490 2491 If <bit> is true, sets the I2C clock line high. If it 2492 is false, it clears it (low). 2493 2494 eg: #define I2C_SCL(bit) \ 2495 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2496 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2497 2498 I2C_DELAY 2499 2500 This delay is invoked four times per clock cycle so this 2501 controls the rate of data transfer. The data rate thus 2502 is 1 / (I2C_DELAY * 4). Often defined to be something 2503 like: 2504 2505 #define I2C_DELAY udelay(2) 2506 2507 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2508 2509 If your arch supports the generic GPIO framework (asm/gpio.h), 2510 then you may alternatively define the two GPIOs that are to be 2511 used as SCL / SDA. Any of the previous I2C_xxx macros will 2512 have GPIO-based defaults assigned to them as appropriate. 2513 2514 You should define these to the GPIO value as given directly to 2515 the generic GPIO functions. 2516 2517 CONFIG_SYS_I2C_INIT_BOARD 2518 2519 When a board is reset during an i2c bus transfer 2520 chips might think that the current transfer is still 2521 in progress. On some boards it is possible to access 2522 the i2c SCLK line directly, either by using the 2523 processor pin as a GPIO or by having a second pin 2524 connected to the bus. If this option is defined a 2525 custom i2c_init_board() routine in boards/xxx/board.c 2526 is run early in the boot sequence. 2527 2528 CONFIG_SYS_I2C_BOARD_LATE_INIT 2529 2530 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2531 defined a custom i2c_board_late_init() routine in 2532 boards/xxx/board.c is run AFTER the operations in i2c_init() 2533 is completed. This callpoint can be used to unreset i2c bus 2534 using CPU i2c controller register accesses for CPUs whose i2c 2535 controller provide such a method. It is called at the end of 2536 i2c_init() to allow i2c_init operations to setup the i2c bus 2537 controller on the CPU (e.g. setting bus speed & slave address). 2538 2539 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2540 2541 This option enables configuration of bi_iic_fast[] flags 2542 in u-boot bd_info structure based on u-boot environment 2543 variable "i2cfast". (see also i2cfast) 2544 2545 CONFIG_I2C_MULTI_BUS 2546 2547 This option allows the use of multiple I2C buses, each of which 2548 must have a controller. At any point in time, only one bus is 2549 active. To switch to a different bus, use the 'i2c dev' command. 2550 Note that bus numbering is zero-based. 2551 2552 CONFIG_SYS_I2C_NOPROBES 2553 2554 This option specifies a list of I2C devices that will be skipped 2555 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2556 is set, specify a list of bus-device pairs. Otherwise, specify 2557 a 1D array of device addresses 2558 2559 e.g. 2560 #undef CONFIG_I2C_MULTI_BUS 2561 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2562 2563 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2564 2565 #define CONFIG_I2C_MULTI_BUS 2566 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2567 2568 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2569 2570 CONFIG_SYS_SPD_BUS_NUM 2571 2572 If defined, then this indicates the I2C bus number for DDR SPD. 2573 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2574 2575 CONFIG_SYS_RTC_BUS_NUM 2576 2577 If defined, then this indicates the I2C bus number for the RTC. 2578 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2579 2580 CONFIG_SYS_DTT_BUS_NUM 2581 2582 If defined, then this indicates the I2C bus number for the DTT. 2583 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2584 2585 CONFIG_SYS_I2C_DTT_ADDR: 2586 2587 If defined, specifies the I2C address of the DTT device. 2588 If not defined, then U-Boot uses predefined value for 2589 specified DTT device. 2590 2591 CONFIG_SOFT_I2C_READ_REPEATED_START 2592 2593 defining this will force the i2c_read() function in 2594 the soft_i2c driver to perform an I2C repeated start 2595 between writing the address pointer and reading the 2596 data. If this define is omitted the default behaviour 2597 of doing a stop-start sequence will be used. Most I2C 2598 devices can use either method, but some require one or 2599 the other. 2600 2601- SPI Support: CONFIG_SPI 2602 2603 Enables SPI driver (so far only tested with 2604 SPI EEPROM, also an instance works with Crystal A/D and 2605 D/As on the SACSng board) 2606 2607 CONFIG_SH_SPI 2608 2609 Enables the driver for SPI controller on SuperH. Currently 2610 only SH7757 is supported. 2611 2612 CONFIG_SPI_X 2613 2614 Enables extended (16-bit) SPI EEPROM addressing. 2615 (symmetrical to CONFIG_I2C_X) 2616 2617 CONFIG_SOFT_SPI 2618 2619 Enables a software (bit-bang) SPI driver rather than 2620 using hardware support. This is a general purpose 2621 driver that only requires three general I/O port pins 2622 (two outputs, one input) to function. If this is 2623 defined, the board configuration must define several 2624 SPI configuration items (port pins to use, etc). For 2625 an example, see include/configs/sacsng.h. 2626 2627 CONFIG_HARD_SPI 2628 2629 Enables a hardware SPI driver for general-purpose reads 2630 and writes. As with CONFIG_SOFT_SPI, the board configuration 2631 must define a list of chip-select function pointers. 2632 Currently supported on some MPC8xxx processors. For an 2633 example, see include/configs/mpc8349emds.h. 2634 2635 CONFIG_MXC_SPI 2636 2637 Enables the driver for the SPI controllers on i.MX and MXC 2638 SoCs. Currently i.MX31/35/51 are supported. 2639 2640 CONFIG_SYS_SPI_MXC_WAIT 2641 Timeout for waiting until spi transfer completed. 2642 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2643 2644- FPGA Support: CONFIG_FPGA 2645 2646 Enables FPGA subsystem. 2647 2648 CONFIG_FPGA_<vendor> 2649 2650 Enables support for specific chip vendors. 2651 (ALTERA, XILINX) 2652 2653 CONFIG_FPGA_<family> 2654 2655 Enables support for FPGA family. 2656 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2657 2658 CONFIG_FPGA_COUNT 2659 2660 Specify the number of FPGA devices to support. 2661 2662 CONFIG_CMD_FPGA_LOADMK 2663 2664 Enable support for fpga loadmk command 2665 2666 CONFIG_CMD_FPGA_LOADP 2667 2668 Enable support for fpga loadp command - load partial bitstream 2669 2670 CONFIG_CMD_FPGA_LOADBP 2671 2672 Enable support for fpga loadbp command - load partial bitstream 2673 (Xilinx only) 2674 2675 CONFIG_SYS_FPGA_PROG_FEEDBACK 2676 2677 Enable printing of hash marks during FPGA configuration. 2678 2679 CONFIG_SYS_FPGA_CHECK_BUSY 2680 2681 Enable checks on FPGA configuration interface busy 2682 status by the configuration function. This option 2683 will require a board or device specific function to 2684 be written. 2685 2686 CONFIG_FPGA_DELAY 2687 2688 If defined, a function that provides delays in the FPGA 2689 configuration driver. 2690 2691 CONFIG_SYS_FPGA_CHECK_CTRLC 2692 Allow Control-C to interrupt FPGA configuration 2693 2694 CONFIG_SYS_FPGA_CHECK_ERROR 2695 2696 Check for configuration errors during FPGA bitfile 2697 loading. For example, abort during Virtex II 2698 configuration if the INIT_B line goes low (which 2699 indicated a CRC error). 2700 2701 CONFIG_SYS_FPGA_WAIT_INIT 2702 2703 Maximum time to wait for the INIT_B line to deassert 2704 after PROB_B has been deasserted during a Virtex II 2705 FPGA configuration sequence. The default time is 500 2706 ms. 2707 2708 CONFIG_SYS_FPGA_WAIT_BUSY 2709 2710 Maximum time to wait for BUSY to deassert during 2711 Virtex II FPGA configuration. The default is 5 ms. 2712 2713 CONFIG_SYS_FPGA_WAIT_CONFIG 2714 2715 Time to wait after FPGA configuration. The default is 2716 200 ms. 2717 2718- Configuration Management: 2719 CONFIG_IDENT_STRING 2720 2721 If defined, this string will be added to the U-Boot 2722 version information (U_BOOT_VERSION) 2723 2724- Vendor Parameter Protection: 2725 2726 U-Boot considers the values of the environment 2727 variables "serial#" (Board Serial Number) and 2728 "ethaddr" (Ethernet Address) to be parameters that 2729 are set once by the board vendor / manufacturer, and 2730 protects these variables from casual modification by 2731 the user. Once set, these variables are read-only, 2732 and write or delete attempts are rejected. You can 2733 change this behaviour: 2734 2735 If CONFIG_ENV_OVERWRITE is #defined in your config 2736 file, the write protection for vendor parameters is 2737 completely disabled. Anybody can change or delete 2738 these parameters. 2739 2740 Alternatively, if you #define _both_ CONFIG_ETHADDR 2741 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2742 Ethernet address is installed in the environment, 2743 which can be changed exactly ONCE by the user. [The 2744 serial# is unaffected by this, i. e. it remains 2745 read-only.] 2746 2747 The same can be accomplished in a more flexible way 2748 for any variable by configuring the type of access 2749 to allow for those variables in the ".flags" variable 2750 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2751 2752- Protected RAM: 2753 CONFIG_PRAM 2754 2755 Define this variable to enable the reservation of 2756 "protected RAM", i. e. RAM which is not overwritten 2757 by U-Boot. Define CONFIG_PRAM to hold the number of 2758 kB you want to reserve for pRAM. You can overwrite 2759 this default value by defining an environment 2760 variable "pram" to the number of kB you want to 2761 reserve. Note that the board info structure will 2762 still show the full amount of RAM. If pRAM is 2763 reserved, a new environment variable "mem" will 2764 automatically be defined to hold the amount of 2765 remaining RAM in a form that can be passed as boot 2766 argument to Linux, for instance like that: 2767 2768 setenv bootargs ... mem=\${mem} 2769 saveenv 2770 2771 This way you can tell Linux not to use this memory, 2772 either, which results in a memory region that will 2773 not be affected by reboots. 2774 2775 *WARNING* If your board configuration uses automatic 2776 detection of the RAM size, you must make sure that 2777 this memory test is non-destructive. So far, the 2778 following board configurations are known to be 2779 "pRAM-clean": 2780 2781 IVMS8, IVML24, SPD8xx, TQM8xxL, 2782 HERMES, IP860, RPXlite, LWMON, 2783 FLAGADM, TQM8260 2784 2785- Access to physical memory region (> 4GB) 2786 Some basic support is provided for operations on memory not 2787 normally accessible to U-Boot - e.g. some architectures 2788 support access to more than 4GB of memory on 32-bit 2789 machines using physical address extension or similar. 2790 Define CONFIG_PHYSMEM to access this basic support, which 2791 currently only supports clearing the memory. 2792 2793- Error Recovery: 2794 CONFIG_PANIC_HANG 2795 2796 Define this variable to stop the system in case of a 2797 fatal error, so that you have to reset it manually. 2798 This is probably NOT a good idea for an embedded 2799 system where you want the system to reboot 2800 automatically as fast as possible, but it may be 2801 useful during development since you can try to debug 2802 the conditions that lead to the situation. 2803 2804 CONFIG_NET_RETRY_COUNT 2805 2806 This variable defines the number of retries for 2807 network operations like ARP, RARP, TFTP, or BOOTP 2808 before giving up the operation. If not defined, a 2809 default value of 5 is used. 2810 2811 CONFIG_ARP_TIMEOUT 2812 2813 Timeout waiting for an ARP reply in milliseconds. 2814 2815 CONFIG_NFS_TIMEOUT 2816 2817 Timeout in milliseconds used in NFS protocol. 2818 If you encounter "ERROR: Cannot umount" in nfs command, 2819 try longer timeout such as 2820 #define CONFIG_NFS_TIMEOUT 10000UL 2821 2822- Command Interpreter: 2823 CONFIG_AUTO_COMPLETE 2824 2825 Enable auto completion of commands using TAB. 2826 2827 Note that this feature has NOT been implemented yet 2828 for the "hush" shell. 2829 2830 2831 CONFIG_SYS_HUSH_PARSER 2832 2833 Define this variable to enable the "hush" shell (from 2834 Busybox) as command line interpreter, thus enabling 2835 powerful command line syntax like 2836 if...then...else...fi conditionals or `&&' and '||' 2837 constructs ("shell scripts"). 2838 2839 If undefined, you get the old, much simpler behaviour 2840 with a somewhat smaller memory footprint. 2841 2842 2843 CONFIG_SYS_PROMPT_HUSH_PS2 2844 2845 This defines the secondary prompt string, which is 2846 printed when the command interpreter needs more input 2847 to complete a command. Usually "> ". 2848 2849 Note: 2850 2851 In the current implementation, the local variables 2852 space and global environment variables space are 2853 separated. Local variables are those you define by 2854 simply typing `name=value'. To access a local 2855 variable later on, you have write `$name' or 2856 `${name}'; to execute the contents of a variable 2857 directly type `$name' at the command prompt. 2858 2859 Global environment variables are those you use 2860 setenv/printenv to work with. To run a command stored 2861 in such a variable, you need to use the run command, 2862 and you must not use the '$' sign to access them. 2863 2864 To store commands and special characters in a 2865 variable, please use double quotation marks 2866 surrounding the whole text of the variable, instead 2867 of the backslashes before semicolons and special 2868 symbols. 2869 2870- Commandline Editing and History: 2871 CONFIG_CMDLINE_EDITING 2872 2873 Enable editing and History functions for interactive 2874 commandline input operations 2875 2876- Default Environment: 2877 CONFIG_EXTRA_ENV_SETTINGS 2878 2879 Define this to contain any number of null terminated 2880 strings (variable = value pairs) that will be part of 2881 the default environment compiled into the boot image. 2882 2883 For example, place something like this in your 2884 board's config file: 2885 2886 #define CONFIG_EXTRA_ENV_SETTINGS \ 2887 "myvar1=value1\0" \ 2888 "myvar2=value2\0" 2889 2890 Warning: This method is based on knowledge about the 2891 internal format how the environment is stored by the 2892 U-Boot code. This is NOT an official, exported 2893 interface! Although it is unlikely that this format 2894 will change soon, there is no guarantee either. 2895 You better know what you are doing here. 2896 2897 Note: overly (ab)use of the default environment is 2898 discouraged. Make sure to check other ways to preset 2899 the environment like the "source" command or the 2900 boot command first. 2901 2902 CONFIG_ENV_VARS_UBOOT_CONFIG 2903 2904 Define this in order to add variables describing the 2905 U-Boot build configuration to the default environment. 2906 These will be named arch, cpu, board, vendor, and soc. 2907 2908 Enabling this option will cause the following to be defined: 2909 2910 - CONFIG_SYS_ARCH 2911 - CONFIG_SYS_CPU 2912 - CONFIG_SYS_BOARD 2913 - CONFIG_SYS_VENDOR 2914 - CONFIG_SYS_SOC 2915 2916 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2917 2918 Define this in order to add variables describing certain 2919 run-time determined information about the hardware to the 2920 environment. These will be named board_name, board_rev. 2921 2922 CONFIG_DELAY_ENVIRONMENT 2923 2924 Normally the environment is loaded when the board is 2925 intialised so that it is available to U-Boot. This inhibits 2926 that so that the environment is not available until 2927 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2928 this is instead controlled by the value of 2929 /config/load-environment. 2930 2931- DataFlash Support: 2932 CONFIG_HAS_DATAFLASH 2933 2934 Defining this option enables DataFlash features and 2935 allows to read/write in Dataflash via the standard 2936 commands cp, md... 2937 2938- Serial Flash support 2939 CONFIG_CMD_SF 2940 2941 Defining this option enables SPI flash commands 2942 'sf probe/read/write/erase/update'. 2943 2944 Usage requires an initial 'probe' to define the serial 2945 flash parameters, followed by read/write/erase/update 2946 commands. 2947 2948 The following defaults may be provided by the platform 2949 to handle the common case when only a single serial 2950 flash is present on the system. 2951 2952 CONFIG_SF_DEFAULT_BUS Bus identifier 2953 CONFIG_SF_DEFAULT_CS Chip-select 2954 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2955 CONFIG_SF_DEFAULT_SPEED in Hz 2956 2957 CONFIG_CMD_SF_TEST 2958 2959 Define this option to include a destructive SPI flash 2960 test ('sf test'). 2961 2962 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 2963 2964 Define this option to use the Bank addr/Extended addr 2965 support on SPI flashes which has size > 16Mbytes. 2966 2967 CONFIG_SF_DUAL_FLASH Dual flash memories 2968 2969 Define this option to use dual flash support where two flash 2970 memories can be connected with a given cs line. 2971 currently Xilinx Zynq qspi support these type of connections. 2972 2973 CONFIG_SYS_SPI_ST_ENABLE_WP_PIN 2974 enable the W#/Vpp signal to disable writing to the status 2975 register on ST MICRON flashes like the N25Q128. 2976 The status register write enable/disable bit, combined with 2977 the W#/VPP signal provides hardware data protection for the 2978 device as follows: When the enable/disable bit is set to 1, 2979 and the W#/VPP signal is driven LOW, the status register 2980 nonvolatile bits become read-only and the WRITE STATUS REGISTER 2981 operation will not execute. The only way to exit this 2982 hardware-protected mode is to drive W#/VPP HIGH. 2983 2984- SystemACE Support: 2985 CONFIG_SYSTEMACE 2986 2987 Adding this option adds support for Xilinx SystemACE 2988 chips attached via some sort of local bus. The address 2989 of the chip must also be defined in the 2990 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2991 2992 #define CONFIG_SYSTEMACE 2993 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2994 2995 When SystemACE support is added, the "ace" device type 2996 becomes available to the fat commands, i.e. fatls. 2997 2998- TFTP Fixed UDP Port: 2999 CONFIG_TFTP_PORT 3000 3001 If this is defined, the environment variable tftpsrcp 3002 is used to supply the TFTP UDP source port value. 3003 If tftpsrcp isn't defined, the normal pseudo-random port 3004 number generator is used. 3005 3006 Also, the environment variable tftpdstp is used to supply 3007 the TFTP UDP destination port value. If tftpdstp isn't 3008 defined, the normal port 69 is used. 3009 3010 The purpose for tftpsrcp is to allow a TFTP server to 3011 blindly start the TFTP transfer using the pre-configured 3012 target IP address and UDP port. This has the effect of 3013 "punching through" the (Windows XP) firewall, allowing 3014 the remainder of the TFTP transfer to proceed normally. 3015 A better solution is to properly configure the firewall, 3016 but sometimes that is not allowed. 3017 3018- Hashing support: 3019 CONFIG_CMD_HASH 3020 3021 This enables a generic 'hash' command which can produce 3022 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 3023 3024 CONFIG_HASH_VERIFY 3025 3026 Enable the hash verify command (hash -v). This adds to code 3027 size a little. 3028 3029 CONFIG_SHA1 - support SHA1 hashing 3030 CONFIG_SHA256 - support SHA256 hashing 3031 3032 Note: There is also a sha1sum command, which should perhaps 3033 be deprecated in favour of 'hash sha1'. 3034 3035- Freescale i.MX specific commands: 3036 CONFIG_CMD_HDMIDETECT 3037 This enables 'hdmidet' command which returns true if an 3038 HDMI monitor is detected. This command is i.MX 6 specific. 3039 3040 CONFIG_CMD_BMODE 3041 This enables the 'bmode' (bootmode) command for forcing 3042 a boot from specific media. 3043 3044 This is useful for forcing the ROM's usb downloader to 3045 activate upon a watchdog reset which is nice when iterating 3046 on U-Boot. Using the reset button or running bmode normal 3047 will set it back to normal. This command currently 3048 supports i.MX53 and i.MX6. 3049 3050- Signing support: 3051 CONFIG_RSA 3052 3053 This enables the RSA algorithm used for FIT image verification 3054 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 3055 3056 The signing part is build into mkimage regardless of this 3057 option. 3058 3059- bootcount support: 3060 CONFIG_BOOTCOUNT_LIMIT 3061 3062 This enables the bootcounter support, see: 3063 http://www.denx.de/wiki/DULG/UBootBootCountLimit 3064 3065 CONFIG_AT91SAM9XE 3066 enable special bootcounter support on at91sam9xe based boards. 3067 CONFIG_BLACKFIN 3068 enable special bootcounter support on blackfin based boards. 3069 CONFIG_SOC_DA8XX 3070 enable special bootcounter support on da850 based boards. 3071 CONFIG_BOOTCOUNT_RAM 3072 enable support for the bootcounter in RAM 3073 CONFIG_BOOTCOUNT_I2C 3074 enable support for the bootcounter on an i2c (like RTC) device. 3075 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 3076 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 3077 the bootcounter. 3078 CONFIG_BOOTCOUNT_ALEN = address len 3079 3080- Show boot progress: 3081 CONFIG_SHOW_BOOT_PROGRESS 3082 3083 Defining this option allows to add some board- 3084 specific code (calling a user-provided function 3085 "show_boot_progress(int)") that enables you to show 3086 the system's boot progress on some display (for 3087 example, some LED's) on your board. At the moment, 3088 the following checkpoints are implemented: 3089 3090- Detailed boot stage timing 3091 CONFIG_BOOTSTAGE 3092 Define this option to get detailed timing of each stage 3093 of the boot process. 3094 3095 CONFIG_BOOTSTAGE_USER_COUNT 3096 This is the number of available user bootstage records. 3097 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 3098 a new ID will be allocated from this stash. If you exceed 3099 the limit, recording will stop. 3100 3101 CONFIG_BOOTSTAGE_REPORT 3102 Define this to print a report before boot, similar to this: 3103 3104 Timer summary in microseconds: 3105 Mark Elapsed Stage 3106 0 0 reset 3107 3,575,678 3,575,678 board_init_f start 3108 3,575,695 17 arch_cpu_init A9 3109 3,575,777 82 arch_cpu_init done 3110 3,659,598 83,821 board_init_r start 3111 3,910,375 250,777 main_loop 3112 29,916,167 26,005,792 bootm_start 3113 30,361,327 445,160 start_kernel 3114 3115 CONFIG_CMD_BOOTSTAGE 3116 Add a 'bootstage' command which supports printing a report 3117 and un/stashing of bootstage data. 3118 3119 CONFIG_BOOTSTAGE_FDT 3120 Stash the bootstage information in the FDT. A root 'bootstage' 3121 node is created with each bootstage id as a child. Each child 3122 has a 'name' property and either 'mark' containing the 3123 mark time in microsecond, or 'accum' containing the 3124 accumulated time for that bootstage id in microseconds. 3125 For example: 3126 3127 bootstage { 3128 154 { 3129 name = "board_init_f"; 3130 mark = <3575678>; 3131 }; 3132 170 { 3133 name = "lcd"; 3134 accum = <33482>; 3135 }; 3136 }; 3137 3138 Code in the Linux kernel can find this in /proc/devicetree. 3139 3140Legacy uImage format: 3141 3142 Arg Where When 3143 1 common/cmd_bootm.c before attempting to boot an image 3144 -1 common/cmd_bootm.c Image header has bad magic number 3145 2 common/cmd_bootm.c Image header has correct magic number 3146 -2 common/cmd_bootm.c Image header has bad checksum 3147 3 common/cmd_bootm.c Image header has correct checksum 3148 -3 common/cmd_bootm.c Image data has bad checksum 3149 4 common/cmd_bootm.c Image data has correct checksum 3150 -4 common/cmd_bootm.c Image is for unsupported architecture 3151 5 common/cmd_bootm.c Architecture check OK 3152 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3153 6 common/cmd_bootm.c Image Type check OK 3154 -6 common/cmd_bootm.c gunzip uncompression error 3155 -7 common/cmd_bootm.c Unimplemented compression type 3156 7 common/cmd_bootm.c Uncompression OK 3157 8 common/cmd_bootm.c No uncompress/copy overwrite error 3158 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3159 3160 9 common/image.c Start initial ramdisk verification 3161 -10 common/image.c Ramdisk header has bad magic number 3162 -11 common/image.c Ramdisk header has bad checksum 3163 10 common/image.c Ramdisk header is OK 3164 -12 common/image.c Ramdisk data has bad checksum 3165 11 common/image.c Ramdisk data has correct checksum 3166 12 common/image.c Ramdisk verification complete, start loading 3167 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3168 13 common/image.c Start multifile image verification 3169 14 common/image.c No initial ramdisk, no multifile, continue. 3170 3171 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3172 3173 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3174 -31 post/post.c POST test failed, detected by post_output_backlog() 3175 -32 post/post.c POST test failed, detected by post_run_single() 3176 3177 34 common/cmd_doc.c before loading a Image from a DOC device 3178 -35 common/cmd_doc.c Bad usage of "doc" command 3179 35 common/cmd_doc.c correct usage of "doc" command 3180 -36 common/cmd_doc.c No boot device 3181 36 common/cmd_doc.c correct boot device 3182 -37 common/cmd_doc.c Unknown Chip ID on boot device 3183 37 common/cmd_doc.c correct chip ID found, device available 3184 -38 common/cmd_doc.c Read Error on boot device 3185 38 common/cmd_doc.c reading Image header from DOC device OK 3186 -39 common/cmd_doc.c Image header has bad magic number 3187 39 common/cmd_doc.c Image header has correct magic number 3188 -40 common/cmd_doc.c Error reading Image from DOC device 3189 40 common/cmd_doc.c Image header has correct magic number 3190 41 common/cmd_ide.c before loading a Image from a IDE device 3191 -42 common/cmd_ide.c Bad usage of "ide" command 3192 42 common/cmd_ide.c correct usage of "ide" command 3193 -43 common/cmd_ide.c No boot device 3194 43 common/cmd_ide.c boot device found 3195 -44 common/cmd_ide.c Device not available 3196 44 common/cmd_ide.c Device available 3197 -45 common/cmd_ide.c wrong partition selected 3198 45 common/cmd_ide.c partition selected 3199 -46 common/cmd_ide.c Unknown partition table 3200 46 common/cmd_ide.c valid partition table found 3201 -47 common/cmd_ide.c Invalid partition type 3202 47 common/cmd_ide.c correct partition type 3203 -48 common/cmd_ide.c Error reading Image Header on boot device 3204 48 common/cmd_ide.c reading Image Header from IDE device OK 3205 -49 common/cmd_ide.c Image header has bad magic number 3206 49 common/cmd_ide.c Image header has correct magic number 3207 -50 common/cmd_ide.c Image header has bad checksum 3208 50 common/cmd_ide.c Image header has correct checksum 3209 -51 common/cmd_ide.c Error reading Image from IDE device 3210 51 common/cmd_ide.c reading Image from IDE device OK 3211 52 common/cmd_nand.c before loading a Image from a NAND device 3212 -53 common/cmd_nand.c Bad usage of "nand" command 3213 53 common/cmd_nand.c correct usage of "nand" command 3214 -54 common/cmd_nand.c No boot device 3215 54 common/cmd_nand.c boot device found 3216 -55 common/cmd_nand.c Unknown Chip ID on boot device 3217 55 common/cmd_nand.c correct chip ID found, device available 3218 -56 common/cmd_nand.c Error reading Image Header on boot device 3219 56 common/cmd_nand.c reading Image Header from NAND device OK 3220 -57 common/cmd_nand.c Image header has bad magic number 3221 57 common/cmd_nand.c Image header has correct magic number 3222 -58 common/cmd_nand.c Error reading Image from NAND device 3223 58 common/cmd_nand.c reading Image from NAND device OK 3224 3225 -60 common/env_common.c Environment has a bad CRC, using default 3226 3227 64 net/eth.c starting with Ethernet configuration. 3228 -64 net/eth.c no Ethernet found. 3229 65 net/eth.c Ethernet found. 3230 3231 -80 common/cmd_net.c usage wrong 3232 80 common/cmd_net.c before calling NetLoop() 3233 -81 common/cmd_net.c some error in NetLoop() occurred 3234 81 common/cmd_net.c NetLoop() back without error 3235 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3236 82 common/cmd_net.c trying automatic boot 3237 83 common/cmd_net.c running "source" command 3238 -83 common/cmd_net.c some error in automatic boot or "source" command 3239 84 common/cmd_net.c end without errors 3240 3241FIT uImage format: 3242 3243 Arg Where When 3244 100 common/cmd_bootm.c Kernel FIT Image has correct format 3245 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3246 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3247 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3248 102 common/cmd_bootm.c Kernel unit name specified 3249 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3250 103 common/cmd_bootm.c Found configuration node 3251 104 common/cmd_bootm.c Got kernel subimage node offset 3252 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3253 105 common/cmd_bootm.c Kernel subimage hash verification OK 3254 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3255 106 common/cmd_bootm.c Architecture check OK 3256 -106 common/cmd_bootm.c Kernel subimage has wrong type 3257 107 common/cmd_bootm.c Kernel subimage type OK 3258 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3259 108 common/cmd_bootm.c Got kernel subimage data/size 3260 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3261 -109 common/cmd_bootm.c Can't get kernel subimage type 3262 -110 common/cmd_bootm.c Can't get kernel subimage comp 3263 -111 common/cmd_bootm.c Can't get kernel subimage os 3264 -112 common/cmd_bootm.c Can't get kernel subimage load address 3265 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3266 3267 120 common/image.c Start initial ramdisk verification 3268 -120 common/image.c Ramdisk FIT image has incorrect format 3269 121 common/image.c Ramdisk FIT image has correct format 3270 122 common/image.c No ramdisk subimage unit name, using configuration 3271 -122 common/image.c Can't get configuration for ramdisk subimage 3272 123 common/image.c Ramdisk unit name specified 3273 -124 common/image.c Can't get ramdisk subimage node offset 3274 125 common/image.c Got ramdisk subimage node offset 3275 -125 common/image.c Ramdisk subimage hash verification failed 3276 126 common/image.c Ramdisk subimage hash verification OK 3277 -126 common/image.c Ramdisk subimage for unsupported architecture 3278 127 common/image.c Architecture check OK 3279 -127 common/image.c Can't get ramdisk subimage data/size 3280 128 common/image.c Got ramdisk subimage data/size 3281 129 common/image.c Can't get ramdisk load address 3282 -129 common/image.c Got ramdisk load address 3283 3284 -130 common/cmd_doc.c Incorrect FIT image format 3285 131 common/cmd_doc.c FIT image format OK 3286 3287 -140 common/cmd_ide.c Incorrect FIT image format 3288 141 common/cmd_ide.c FIT image format OK 3289 3290 -150 common/cmd_nand.c Incorrect FIT image format 3291 151 common/cmd_nand.c FIT image format OK 3292 3293- legacy image format: 3294 CONFIG_IMAGE_FORMAT_LEGACY 3295 enables the legacy image format support in U-Boot. 3296 3297 Default: 3298 enabled if CONFIG_FIT_SIGNATURE is not defined. 3299 3300 CONFIG_DISABLE_IMAGE_LEGACY 3301 disable the legacy image format 3302 3303 This define is introduced, as the legacy image format is 3304 enabled per default for backward compatibility. 3305 3306- FIT image support: 3307 CONFIG_FIT 3308 Enable support for the FIT uImage format. 3309 3310 CONFIG_FIT_BEST_MATCH 3311 When no configuration is explicitly selected, default to the 3312 one whose fdt's compatibility field best matches that of 3313 U-Boot itself. A match is considered "best" if it matches the 3314 most specific compatibility entry of U-Boot's fdt's root node. 3315 The order of entries in the configuration's fdt is ignored. 3316 3317 CONFIG_FIT_SIGNATURE 3318 This option enables signature verification of FIT uImages, 3319 using a hash signed and verified using RSA. See 3320 doc/uImage.FIT/signature.txt for more details. 3321 3322 WARNING: When relying on signed FIT images with required 3323 signature check the legacy image format is default 3324 disabled. If a board need legacy image format support 3325 enable this through CONFIG_IMAGE_FORMAT_LEGACY 3326 3327 CONFIG_FIT_DISABLE_SHA256 3328 Supporting SHA256 hashes has quite an impact on binary size. 3329 For constrained systems sha256 hash support can be disabled 3330 with this option. 3331 3332- Standalone program support: 3333 CONFIG_STANDALONE_LOAD_ADDR 3334 3335 This option defines a board specific value for the 3336 address where standalone program gets loaded, thus 3337 overwriting the architecture dependent default 3338 settings. 3339 3340- Frame Buffer Address: 3341 CONFIG_FB_ADDR 3342 3343 Define CONFIG_FB_ADDR if you want to use specific 3344 address for frame buffer. This is typically the case 3345 when using a graphics controller has separate video 3346 memory. U-Boot will then place the frame buffer at 3347 the given address instead of dynamically reserving it 3348 in system RAM by calling lcd_setmem(), which grabs 3349 the memory for the frame buffer depending on the 3350 configured panel size. 3351 3352 Please see board_init_f function. 3353 3354- Automatic software updates via TFTP server 3355 CONFIG_UPDATE_TFTP 3356 CONFIG_UPDATE_TFTP_CNT_MAX 3357 CONFIG_UPDATE_TFTP_MSEC_MAX 3358 3359 These options enable and control the auto-update feature; 3360 for a more detailed description refer to doc/README.update. 3361 3362- MTD Support (mtdparts command, UBI support) 3363 CONFIG_MTD_DEVICE 3364 3365 Adds the MTD device infrastructure from the Linux kernel. 3366 Needed for mtdparts command support. 3367 3368 CONFIG_MTD_PARTITIONS 3369 3370 Adds the MTD partitioning infrastructure from the Linux 3371 kernel. Needed for UBI support. 3372 3373 CONFIG_MTD_NAND_VERIFY_WRITE 3374 verify if the written data is correct reread. 3375 3376- UBI support 3377 CONFIG_CMD_UBI 3378 3379 Adds commands for interacting with MTD partitions formatted 3380 with the UBI flash translation layer 3381 3382 Requires also defining CONFIG_RBTREE 3383 3384 CONFIG_UBI_SILENCE_MSG 3385 3386 Make the verbose messages from UBI stop printing. This leaves 3387 warnings and errors enabled. 3388 3389 3390 CONFIG_MTD_UBI_WL_THRESHOLD 3391 This parameter defines the maximum difference between the highest 3392 erase counter value and the lowest erase counter value of eraseblocks 3393 of UBI devices. When this threshold is exceeded, UBI starts performing 3394 wear leveling by means of moving data from eraseblock with low erase 3395 counter to eraseblocks with high erase counter. 3396 3397 The default value should be OK for SLC NAND flashes, NOR flashes and 3398 other flashes which have eraseblock life-cycle 100000 or more. 3399 However, in case of MLC NAND flashes which typically have eraseblock 3400 life-cycle less than 10000, the threshold should be lessened (e.g., 3401 to 128 or 256, although it does not have to be power of 2). 3402 3403 default: 4096 3404 3405 CONFIG_MTD_UBI_BEB_LIMIT 3406 This option specifies the maximum bad physical eraseblocks UBI 3407 expects on the MTD device (per 1024 eraseblocks). If the 3408 underlying flash does not admit of bad eraseblocks (e.g. NOR 3409 flash), this value is ignored. 3410 3411 NAND datasheets often specify the minimum and maximum NVM 3412 (Number of Valid Blocks) for the flashes' endurance lifetime. 3413 The maximum expected bad eraseblocks per 1024 eraseblocks 3414 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3415 which gives 20 for most NANDs (MaxNVB is basically the total 3416 count of eraseblocks on the chip). 3417 3418 To put it differently, if this value is 20, UBI will try to 3419 reserve about 1.9% of physical eraseblocks for bad blocks 3420 handling. And that will be 1.9% of eraseblocks on the entire 3421 NAND chip, not just the MTD partition UBI attaches. This means 3422 that if you have, say, a NAND flash chip admits maximum 40 bad 3423 eraseblocks, and it is split on two MTD partitions of the same 3424 size, UBI will reserve 40 eraseblocks when attaching a 3425 partition. 3426 3427 default: 20 3428 3429 CONFIG_MTD_UBI_FASTMAP 3430 Fastmap is a mechanism which allows attaching an UBI device 3431 in nearly constant time. Instead of scanning the whole MTD device it 3432 only has to locate a checkpoint (called fastmap) on the device. 3433 The on-flash fastmap contains all information needed to attach 3434 the device. Using fastmap makes only sense on large devices where 3435 attaching by scanning takes long. UBI will not automatically install 3436 a fastmap on old images, but you can set the UBI parameter 3437 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3438 that fastmap-enabled images are still usable with UBI implementations 3439 without fastmap support. On typical flash devices the whole fastmap 3440 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3441 3442 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3443 Set this parameter to enable fastmap automatically on images 3444 without a fastmap. 3445 default: 0 3446 3447- UBIFS support 3448 CONFIG_CMD_UBIFS 3449 3450 Adds commands for interacting with UBI volumes formatted as 3451 UBIFS. UBIFS is read-only in u-boot. 3452 3453 Requires UBI support as well as CONFIG_LZO 3454 3455 CONFIG_UBIFS_SILENCE_MSG 3456 3457 Make the verbose messages from UBIFS stop printing. This leaves 3458 warnings and errors enabled. 3459 3460- SPL framework 3461 CONFIG_SPL 3462 Enable building of SPL globally. 3463 3464 CONFIG_SPL_LDSCRIPT 3465 LDSCRIPT for linking the SPL binary. 3466 3467 CONFIG_SPL_MAX_FOOTPRINT 3468 Maximum size in memory allocated to the SPL, BSS included. 3469 When defined, the linker checks that the actual memory 3470 used by SPL from _start to __bss_end does not exceed it. 3471 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3472 must not be both defined at the same time. 3473 3474 CONFIG_SPL_MAX_SIZE 3475 Maximum size of the SPL image (text, data, rodata, and 3476 linker lists sections), BSS excluded. 3477 When defined, the linker checks that the actual size does 3478 not exceed it. 3479 3480 CONFIG_SPL_TEXT_BASE 3481 TEXT_BASE for linking the SPL binary. 3482 3483 CONFIG_SPL_RELOC_TEXT_BASE 3484 Address to relocate to. If unspecified, this is equal to 3485 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3486 3487 CONFIG_SPL_BSS_START_ADDR 3488 Link address for the BSS within the SPL binary. 3489 3490 CONFIG_SPL_BSS_MAX_SIZE 3491 Maximum size in memory allocated to the SPL BSS. 3492 When defined, the linker checks that the actual memory used 3493 by SPL from __bss_start to __bss_end does not exceed it. 3494 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3495 must not be both defined at the same time. 3496 3497 CONFIG_SPL_STACK 3498 Adress of the start of the stack SPL will use 3499 3500 CONFIG_SPL_RELOC_STACK 3501 Adress of the start of the stack SPL will use after 3502 relocation. If unspecified, this is equal to 3503 CONFIG_SPL_STACK. 3504 3505 CONFIG_SYS_SPL_MALLOC_START 3506 Starting address of the malloc pool used in SPL. 3507 3508 CONFIG_SYS_SPL_MALLOC_SIZE 3509 The size of the malloc pool used in SPL. 3510 3511 CONFIG_SPL_FRAMEWORK 3512 Enable the SPL framework under common/. This framework 3513 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3514 NAND loading of the Linux Kernel. 3515 3516 CONFIG_SPL_OS_BOOT 3517 Enable booting directly to an OS from SPL. 3518 See also: doc/README.falcon 3519 3520 CONFIG_SPL_DISPLAY_PRINT 3521 For ARM, enable an optional function to print more information 3522 about the running system. 3523 3524 CONFIG_SPL_INIT_MINIMAL 3525 Arch init code should be built for a very small image 3526 3527 CONFIG_SPL_LIBCOMMON_SUPPORT 3528 Support for common/libcommon.o in SPL binary 3529 3530 CONFIG_SPL_LIBDISK_SUPPORT 3531 Support for disk/libdisk.o in SPL binary 3532 3533 CONFIG_SPL_I2C_SUPPORT 3534 Support for drivers/i2c/libi2c.o in SPL binary 3535 3536 CONFIG_SPL_GPIO_SUPPORT 3537 Support for drivers/gpio/libgpio.o in SPL binary 3538 3539 CONFIG_SPL_MMC_SUPPORT 3540 Support for drivers/mmc/libmmc.o in SPL binary 3541 3542 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3543 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3544 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 3545 Address, size and partition on the MMC to load U-Boot from 3546 when the MMC is being used in raw mode. 3547 3548 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3549 Sector to load kernel uImage from when MMC is being 3550 used in raw mode (for Falcon mode) 3551 3552 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3553 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3554 Sector and number of sectors to load kernel argument 3555 parameters from when MMC is being used in raw mode 3556 (for falcon mode) 3557 3558 CONFIG_SPL_FAT_SUPPORT 3559 Support for fs/fat/libfat.o in SPL binary 3560 3561 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 3562 Filename to read to load U-Boot when reading from FAT 3563 3564 CONFIG_SPL_FAT_LOAD_KERNEL_NAME 3565 Filename to read to load kernel uImage when reading 3566 from FAT (for Falcon mode) 3567 3568 CONFIG_SPL_FAT_LOAD_ARGS_NAME 3569 Filename to read to load kernel argument parameters 3570 when reading from FAT (for Falcon mode) 3571 3572 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3573 Set this for NAND SPL on PPC mpc83xx targets, so that 3574 start.S waits for the rest of the SPL to load before 3575 continuing (the hardware starts execution after just 3576 loading the first page rather than the full 4K). 3577 3578 CONFIG_SPL_SKIP_RELOCATE 3579 Avoid SPL relocation 3580 3581 CONFIG_SPL_NAND_BASE 3582 Include nand_base.c in the SPL. Requires 3583 CONFIG_SPL_NAND_DRIVERS. 3584 3585 CONFIG_SPL_NAND_DRIVERS 3586 SPL uses normal NAND drivers, not minimal drivers. 3587 3588 CONFIG_SPL_NAND_ECC 3589 Include standard software ECC in the SPL 3590 3591 CONFIG_SPL_NAND_SIMPLE 3592 Support for NAND boot using simple NAND drivers that 3593 expose the cmd_ctrl() interface. 3594 3595 CONFIG_SPL_MTD_SUPPORT 3596 Support for the MTD subsystem within SPL. Useful for 3597 environment on NAND support within SPL. 3598 3599 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3600 Set for the SPL on PPC mpc8xxx targets, support for 3601 drivers/ddr/fsl/libddr.o in SPL binary. 3602 3603 CONFIG_SPL_COMMON_INIT_DDR 3604 Set for common ddr init with serial presence detect in 3605 SPL binary. 3606 3607 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3608 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3609 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3610 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3611 CONFIG_SYS_NAND_ECCBYTES 3612 Defines the size and behavior of the NAND that SPL uses 3613 to read U-Boot 3614 3615 CONFIG_SPL_NAND_BOOT 3616 Add support NAND boot 3617 3618 CONFIG_SYS_NAND_U_BOOT_OFFS 3619 Location in NAND to read U-Boot from 3620 3621 CONFIG_SYS_NAND_U_BOOT_DST 3622 Location in memory to load U-Boot to 3623 3624 CONFIG_SYS_NAND_U_BOOT_SIZE 3625 Size of image to load 3626 3627 CONFIG_SYS_NAND_U_BOOT_START 3628 Entry point in loaded image to jump to 3629 3630 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3631 Define this if you need to first read the OOB and then the 3632 data. This is used for example on davinci plattforms. 3633 3634 CONFIG_SPL_OMAP3_ID_NAND 3635 Support for an OMAP3-specific set of functions to return the 3636 ID and MFR of the first attached NAND chip, if present. 3637 3638 CONFIG_SPL_SERIAL_SUPPORT 3639 Support for drivers/serial/libserial.o in SPL binary 3640 3641 CONFIG_SPL_SPI_FLASH_SUPPORT 3642 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3643 3644 CONFIG_SPL_SPI_SUPPORT 3645 Support for drivers/spi/libspi.o in SPL binary 3646 3647 CONFIG_SPL_RAM_DEVICE 3648 Support for running image already present in ram, in SPL binary 3649 3650 CONFIG_SPL_LIBGENERIC_SUPPORT 3651 Support for lib/libgeneric.o in SPL binary 3652 3653 CONFIG_SPL_ENV_SUPPORT 3654 Support for the environment operating in SPL binary 3655 3656 CONFIG_SPL_NET_SUPPORT 3657 Support for the net/libnet.o in SPL binary. 3658 It conflicts with SPL env from storage medium specified by 3659 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3660 3661 CONFIG_SPL_PAD_TO 3662 Image offset to which the SPL should be padded before appending 3663 the SPL payload. By default, this is defined as 3664 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3665 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3666 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3667 3668 CONFIG_SPL_TARGET 3669 Final target image containing SPL and payload. Some SPLs 3670 use an arch-specific makefile fragment instead, for 3671 example if more than one image needs to be produced. 3672 3673 CONFIG_FIT_SPL_PRINT 3674 Printing information about a FIT image adds quite a bit of 3675 code to SPL. So this is normally disabled in SPL. Use this 3676 option to re-enable it. This will affect the output of the 3677 bootm command when booting a FIT image. 3678 3679- TPL framework 3680 CONFIG_TPL 3681 Enable building of TPL globally. 3682 3683 CONFIG_TPL_PAD_TO 3684 Image offset to which the TPL should be padded before appending 3685 the TPL payload. By default, this is defined as 3686 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3687 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3688 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3689 3690Modem Support: 3691-------------- 3692 3693[so far only for SMDK2400 boards] 3694 3695- Modem support enable: 3696 CONFIG_MODEM_SUPPORT 3697 3698- RTS/CTS Flow control enable: 3699 CONFIG_HWFLOW 3700 3701- Modem debug support: 3702 CONFIG_MODEM_SUPPORT_DEBUG 3703 3704 Enables debugging stuff (char screen[1024], dbg()) 3705 for modem support. Useful only with BDI2000. 3706 3707- Interrupt support (PPC): 3708 3709 There are common interrupt_init() and timer_interrupt() 3710 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3711 for CPU specific initialization. interrupt_init_cpu() 3712 should set decrementer_count to appropriate value. If 3713 CPU resets decrementer automatically after interrupt 3714 (ppc4xx) it should set decrementer_count to zero. 3715 timer_interrupt() calls timer_interrupt_cpu() for CPU 3716 specific handling. If board has watchdog / status_led 3717 / other_activity_monitor it works automatically from 3718 general timer_interrupt(). 3719 3720- General: 3721 3722 In the target system modem support is enabled when a 3723 specific key (key combination) is pressed during 3724 power-on. Otherwise U-Boot will boot normally 3725 (autoboot). The key_pressed() function is called from 3726 board_init(). Currently key_pressed() is a dummy 3727 function, returning 1 and thus enabling modem 3728 initialization. 3729 3730 If there are no modem init strings in the 3731 environment, U-Boot proceed to autoboot; the 3732 previous output (banner, info printfs) will be 3733 suppressed, though. 3734 3735 See also: doc/README.Modem 3736 3737Board initialization settings: 3738------------------------------ 3739 3740During Initialization u-boot calls a number of board specific functions 3741to allow the preparation of board specific prerequisites, e.g. pin setup 3742before drivers are initialized. To enable these callbacks the 3743following configuration macros have to be defined. Currently this is 3744architecture specific, so please check arch/your_architecture/lib/board.c 3745typically in board_init_f() and board_init_r(). 3746 3747- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3748- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3749- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3750- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3751 3752Configuration Settings: 3753----------------------- 3754 3755- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3756 Optionally it can be defined to support 64-bit memory commands. 3757 3758- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3759 undefine this when you're short of memory. 3760 3761- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3762 width of the commands listed in the 'help' command output. 3763 3764- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3765 prompt for user input. 3766 3767- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3768 3769- CONFIG_SYS_PBSIZE: Buffer size for Console output 3770 3771- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3772 3773- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3774 the application (usually a Linux kernel) when it is 3775 booted 3776 3777- CONFIG_SYS_BAUDRATE_TABLE: 3778 List of legal baudrate settings for this board. 3779 3780- CONFIG_SYS_CONSOLE_INFO_QUIET 3781 Suppress display of console information at boot. 3782 3783- CONFIG_SYS_CONSOLE_IS_IN_ENV 3784 If the board specific function 3785 extern int overwrite_console (void); 3786 returns 1, the stdin, stderr and stdout are switched to the 3787 serial port, else the settings in the environment are used. 3788 3789- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3790 Enable the call to overwrite_console(). 3791 3792- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3793 Enable overwrite of previous console environment settings. 3794 3795- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3796 Begin and End addresses of the area used by the 3797 simple memory test. 3798 3799- CONFIG_SYS_ALT_MEMTEST: 3800 Enable an alternate, more extensive memory test. 3801 3802- CONFIG_SYS_MEMTEST_SCRATCH: 3803 Scratch address used by the alternate memory test 3804 You only need to set this if address zero isn't writeable 3805 3806- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3807 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3808 this specified memory area will get subtracted from the top 3809 (end) of RAM and won't get "touched" at all by U-Boot. By 3810 fixing up gd->ram_size the Linux kernel should gets passed 3811 the now "corrected" memory size and won't touch it either. 3812 This should work for arch/ppc and arch/powerpc. Only Linux 3813 board ports in arch/powerpc with bootwrapper support that 3814 recalculate the memory size from the SDRAM controller setup 3815 will have to get fixed in Linux additionally. 3816 3817 This option can be used as a workaround for the 440EPx/GRx 3818 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3819 be touched. 3820 3821 WARNING: Please make sure that this value is a multiple of 3822 the Linux page size (normally 4k). If this is not the case, 3823 then the end address of the Linux memory will be located at a 3824 non page size aligned address and this could cause major 3825 problems. 3826 3827- CONFIG_SYS_LOADS_BAUD_CHANGE: 3828 Enable temporary baudrate change while serial download 3829 3830- CONFIG_SYS_SDRAM_BASE: 3831 Physical start address of SDRAM. _Must_ be 0 here. 3832 3833- CONFIG_SYS_MBIO_BASE: 3834 Physical start address of Motherboard I/O (if using a 3835 Cogent motherboard) 3836 3837- CONFIG_SYS_FLASH_BASE: 3838 Physical start address of Flash memory. 3839 3840- CONFIG_SYS_MONITOR_BASE: 3841 Physical start address of boot monitor code (set by 3842 make config files to be same as the text base address 3843 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3844 CONFIG_SYS_FLASH_BASE when booting from flash. 3845 3846- CONFIG_SYS_MONITOR_LEN: 3847 Size of memory reserved for monitor code, used to 3848 determine _at_compile_time_ (!) if the environment is 3849 embedded within the U-Boot image, or in a separate 3850 flash sector. 3851 3852- CONFIG_SYS_MALLOC_LEN: 3853 Size of DRAM reserved for malloc() use. 3854 3855- CONFIG_SYS_MALLOC_F_LEN 3856 Size of the malloc() pool for use before relocation. If 3857 this is defined, then a very simple malloc() implementation 3858 will become available before relocation. The address is just 3859 below the global data, and the stack is moved down to make 3860 space. 3861 3862 This feature allocates regions with increasing addresses 3863 within the region. calloc() is supported, but realloc() 3864 is not available. free() is supported but does nothing. 3865 The memory will be freed (or in fact just forgotton) when 3866 U-Boot relocates itself. 3867 3868 Pre-relocation malloc() is only supported on ARM and sandbox 3869 at present but is fairly easy to enable for other archs. 3870 3871- CONFIG_SYS_BOOTM_LEN: 3872 Normally compressed uImages are limited to an 3873 uncompressed size of 8 MBytes. If this is not enough, 3874 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3875 to adjust this setting to your needs. 3876 3877- CONFIG_SYS_BOOTMAPSZ: 3878 Maximum size of memory mapped by the startup code of 3879 the Linux kernel; all data that must be processed by 3880 the Linux kernel (bd_info, boot arguments, FDT blob if 3881 used) must be put below this limit, unless "bootm_low" 3882 environment variable is defined and non-zero. In such case 3883 all data for the Linux kernel must be between "bootm_low" 3884 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3885 variable "bootm_mapsize" will override the value of 3886 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3887 then the value in "bootm_size" will be used instead. 3888 3889- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3890 Enable initrd_high functionality. If defined then the 3891 initrd_high feature is enabled and the bootm ramdisk subcommand 3892 is enabled. 3893 3894- CONFIG_SYS_BOOT_GET_CMDLINE: 3895 Enables allocating and saving kernel cmdline in space between 3896 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3897 3898- CONFIG_SYS_BOOT_GET_KBD: 3899 Enables allocating and saving a kernel copy of the bd_info in 3900 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3901 3902- CONFIG_SYS_MAX_FLASH_BANKS: 3903 Max number of Flash memory banks 3904 3905- CONFIG_SYS_MAX_FLASH_SECT: 3906 Max number of sectors on a Flash chip 3907 3908- CONFIG_SYS_FLASH_ERASE_TOUT: 3909 Timeout for Flash erase operations (in ms) 3910 3911- CONFIG_SYS_FLASH_WRITE_TOUT: 3912 Timeout for Flash write operations (in ms) 3913 3914- CONFIG_SYS_FLASH_LOCK_TOUT 3915 Timeout for Flash set sector lock bit operation (in ms) 3916 3917- CONFIG_SYS_FLASH_UNLOCK_TOUT 3918 Timeout for Flash clear lock bits operation (in ms) 3919 3920- CONFIG_SYS_FLASH_PROTECTION 3921 If defined, hardware flash sectors protection is used 3922 instead of U-Boot software protection. 3923 3924- CONFIG_SYS_DIRECT_FLASH_TFTP: 3925 3926 Enable TFTP transfers directly to flash memory; 3927 without this option such a download has to be 3928 performed in two steps: (1) download to RAM, and (2) 3929 copy from RAM to flash. 3930 3931 The two-step approach is usually more reliable, since 3932 you can check if the download worked before you erase 3933 the flash, but in some situations (when system RAM is 3934 too limited to allow for a temporary copy of the 3935 downloaded image) this option may be very useful. 3936 3937- CONFIG_SYS_FLASH_CFI: 3938 Define if the flash driver uses extra elements in the 3939 common flash structure for storing flash geometry. 3940 3941- CONFIG_FLASH_CFI_DRIVER 3942 This option also enables the building of the cfi_flash driver 3943 in the drivers directory 3944 3945- CONFIG_FLASH_CFI_MTD 3946 This option enables the building of the cfi_mtd driver 3947 in the drivers directory. The driver exports CFI flash 3948 to the MTD layer. 3949 3950- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3951 Use buffered writes to flash. 3952 3953- CONFIG_FLASH_SPANSION_S29WS_N 3954 s29ws-n MirrorBit flash has non-standard addresses for buffered 3955 write commands. 3956 3957- CONFIG_SYS_FLASH_QUIET_TEST 3958 If this option is defined, the common CFI flash doesn't 3959 print it's warning upon not recognized FLASH banks. This 3960 is useful, if some of the configured banks are only 3961 optionally available. 3962 3963- CONFIG_FLASH_SHOW_PROGRESS 3964 If defined (must be an integer), print out countdown 3965 digits and dots. Recommended value: 45 (9..1) for 80 3966 column displays, 15 (3..1) for 40 column displays. 3967 3968- CONFIG_FLASH_VERIFY 3969 If defined, the content of the flash (destination) is compared 3970 against the source after the write operation. An error message 3971 will be printed when the contents are not identical. 3972 Please note that this option is useless in nearly all cases, 3973 since such flash programming errors usually are detected earlier 3974 while unprotecting/erasing/programming. Please only enable 3975 this option if you really know what you are doing. 3976 3977- CONFIG_SYS_RX_ETH_BUFFER: 3978 Defines the number of Ethernet receive buffers. On some 3979 Ethernet controllers it is recommended to set this value 3980 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3981 buffers can be full shortly after enabling the interface 3982 on high Ethernet traffic. 3983 Defaults to 4 if not defined. 3984 3985- CONFIG_ENV_MAX_ENTRIES 3986 3987 Maximum number of entries in the hash table that is used 3988 internally to store the environment settings. The default 3989 setting is supposed to be generous and should work in most 3990 cases. This setting can be used to tune behaviour; see 3991 lib/hashtable.c for details. 3992 3993- CONFIG_ENV_FLAGS_LIST_DEFAULT 3994- CONFIG_ENV_FLAGS_LIST_STATIC 3995 Enable validation of the values given to environment variables when 3996 calling env set. Variables can be restricted to only decimal, 3997 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3998 the variables can also be restricted to IP address or MAC address. 3999 4000 The format of the list is: 4001 type_attribute = [s|d|x|b|i|m] 4002 access_atribute = [a|r|o|c] 4003 attributes = type_attribute[access_atribute] 4004 entry = variable_name[:attributes] 4005 list = entry[,list] 4006 4007 The type attributes are: 4008 s - String (default) 4009 d - Decimal 4010 x - Hexadecimal 4011 b - Boolean ([1yYtT|0nNfF]) 4012 i - IP address 4013 m - MAC address 4014 4015 The access attributes are: 4016 a - Any (default) 4017 r - Read-only 4018 o - Write-once 4019 c - Change-default 4020 4021 - CONFIG_ENV_FLAGS_LIST_DEFAULT 4022 Define this to a list (string) to define the ".flags" 4023 envirnoment variable in the default or embedded environment. 4024 4025 - CONFIG_ENV_FLAGS_LIST_STATIC 4026 Define this to a list (string) to define validation that 4027 should be done if an entry is not found in the ".flags" 4028 environment variable. To override a setting in the static 4029 list, simply add an entry for the same variable name to the 4030 ".flags" variable. 4031 4032- CONFIG_ENV_ACCESS_IGNORE_FORCE 4033 If defined, don't allow the -f switch to env set override variable 4034 access flags. 4035 4036- CONFIG_SYS_GENERIC_BOARD 4037 This selects the architecture-generic board system instead of the 4038 architecture-specific board files. It is intended to move boards 4039 to this new framework over time. Defining this will disable the 4040 arch/foo/lib/board.c file and use common/board_f.c and 4041 common/board_r.c instead. To use this option your architecture 4042 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in 4043 its config.mk file). If you find problems enabling this option on 4044 your board please report the problem and send patches! 4045 4046- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 4047 This is set by OMAP boards for the max time that reset should 4048 be asserted. See doc/README.omap-reset-time for details on how 4049 the value can be calulated on a given board. 4050 4051The following definitions that deal with the placement and management 4052of environment data (variable area); in general, we support the 4053following configurations: 4054 4055- CONFIG_BUILD_ENVCRC: 4056 4057 Builds up envcrc with the target environment so that external utils 4058 may easily extract it and embed it in final U-Boot images. 4059 4060- CONFIG_ENV_IS_IN_FLASH: 4061 4062 Define this if the environment is in flash memory. 4063 4064 a) The environment occupies one whole flash sector, which is 4065 "embedded" in the text segment with the U-Boot code. This 4066 happens usually with "bottom boot sector" or "top boot 4067 sector" type flash chips, which have several smaller 4068 sectors at the start or the end. For instance, such a 4069 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 4070 such a case you would place the environment in one of the 4071 4 kB sectors - with U-Boot code before and after it. With 4072 "top boot sector" type flash chips, you would put the 4073 environment in one of the last sectors, leaving a gap 4074 between U-Boot and the environment. 4075 4076 - CONFIG_ENV_OFFSET: 4077 4078 Offset of environment data (variable area) to the 4079 beginning of flash memory; for instance, with bottom boot 4080 type flash chips the second sector can be used: the offset 4081 for this sector is given here. 4082 4083 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 4084 4085 - CONFIG_ENV_ADDR: 4086 4087 This is just another way to specify the start address of 4088 the flash sector containing the environment (instead of 4089 CONFIG_ENV_OFFSET). 4090 4091 - CONFIG_ENV_SECT_SIZE: 4092 4093 Size of the sector containing the environment. 4094 4095 4096 b) Sometimes flash chips have few, equal sized, BIG sectors. 4097 In such a case you don't want to spend a whole sector for 4098 the environment. 4099 4100 - CONFIG_ENV_SIZE: 4101 4102 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 4103 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 4104 of this flash sector for the environment. This saves 4105 memory for the RAM copy of the environment. 4106 4107 It may also save flash memory if you decide to use this 4108 when your environment is "embedded" within U-Boot code, 4109 since then the remainder of the flash sector could be used 4110 for U-Boot code. It should be pointed out that this is 4111 STRONGLY DISCOURAGED from a robustness point of view: 4112 updating the environment in flash makes it always 4113 necessary to erase the WHOLE sector. If something goes 4114 wrong before the contents has been restored from a copy in 4115 RAM, your target system will be dead. 4116 4117 - CONFIG_ENV_ADDR_REDUND 4118 CONFIG_ENV_SIZE_REDUND 4119 4120 These settings describe a second storage area used to hold 4121 a redundant copy of the environment data, so that there is 4122 a valid backup copy in case there is a power failure during 4123 a "saveenv" operation. 4124 4125BE CAREFUL! Any changes to the flash layout, and some changes to the 4126source code will make it necessary to adapt <board>/u-boot.lds* 4127accordingly! 4128 4129 4130- CONFIG_ENV_IS_IN_NVRAM: 4131 4132 Define this if you have some non-volatile memory device 4133 (NVRAM, battery buffered SRAM) which you want to use for the 4134 environment. 4135 4136 - CONFIG_ENV_ADDR: 4137 - CONFIG_ENV_SIZE: 4138 4139 These two #defines are used to determine the memory area you 4140 want to use for environment. It is assumed that this memory 4141 can just be read and written to, without any special 4142 provision. 4143 4144BE CAREFUL! The first access to the environment happens quite early 4145in U-Boot initalization (when we try to get the setting of for the 4146console baudrate). You *MUST* have mapped your NVRAM area then, or 4147U-Boot will hang. 4148 4149Please note that even with NVRAM we still use a copy of the 4150environment in RAM: we could work on NVRAM directly, but we want to 4151keep settings there always unmodified except somebody uses "saveenv" 4152to save the current settings. 4153 4154 4155- CONFIG_ENV_IS_IN_EEPROM: 4156 4157 Use this if you have an EEPROM or similar serial access 4158 device and a driver for it. 4159 4160 - CONFIG_ENV_OFFSET: 4161 - CONFIG_ENV_SIZE: 4162 4163 These two #defines specify the offset and size of the 4164 environment area within the total memory of your EEPROM. 4165 4166 - CONFIG_SYS_I2C_EEPROM_ADDR: 4167 If defined, specified the chip address of the EEPROM device. 4168 The default address is zero. 4169 4170 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 4171 If defined, the number of bits used to address bytes in a 4172 single page in the EEPROM device. A 64 byte page, for example 4173 would require six bits. 4174 4175 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 4176 If defined, the number of milliseconds to delay between 4177 page writes. The default is zero milliseconds. 4178 4179 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 4180 The length in bytes of the EEPROM memory array address. Note 4181 that this is NOT the chip address length! 4182 4183 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 4184 EEPROM chips that implement "address overflow" are ones 4185 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 4186 address and the extra bits end up in the "chip address" bit 4187 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 4188 byte chips. 4189 4190 Note that we consider the length of the address field to 4191 still be one byte because the extra address bits are hidden 4192 in the chip address. 4193 4194 - CONFIG_SYS_EEPROM_SIZE: 4195 The size in bytes of the EEPROM device. 4196 4197 - CONFIG_ENV_EEPROM_IS_ON_I2C 4198 define this, if you have I2C and SPI activated, and your 4199 EEPROM, which holds the environment, is on the I2C bus. 4200 4201 - CONFIG_I2C_ENV_EEPROM_BUS 4202 if you have an Environment on an EEPROM reached over 4203 I2C muxes, you can define here, how to reach this 4204 EEPROM. For example: 4205 4206 #define CONFIG_I2C_ENV_EEPROM_BUS 1 4207 4208 EEPROM which holds the environment, is reached over 4209 a pca9547 i2c mux with address 0x70, channel 3. 4210 4211- CONFIG_ENV_IS_IN_DATAFLASH: 4212 4213 Define this if you have a DataFlash memory device which you 4214 want to use for the environment. 4215 4216 - CONFIG_ENV_OFFSET: 4217 - CONFIG_ENV_ADDR: 4218 - CONFIG_ENV_SIZE: 4219 4220 These three #defines specify the offset and size of the 4221 environment area within the total memory of your DataFlash placed 4222 at the specified address. 4223 4224- CONFIG_ENV_IS_IN_SPI_FLASH: 4225 4226 Define this if you have a SPI Flash memory device which you 4227 want to use for the environment. 4228 4229 - CONFIG_ENV_OFFSET: 4230 - CONFIG_ENV_SIZE: 4231 4232 These two #defines specify the offset and size of the 4233 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 4234 aligned to an erase sector boundary. 4235 4236 - CONFIG_ENV_SECT_SIZE: 4237 4238 Define the SPI flash's sector size. 4239 4240 - CONFIG_ENV_OFFSET_REDUND (optional): 4241 4242 This setting describes a second storage area of CONFIG_ENV_SIZE 4243 size used to hold a redundant copy of the environment data, so 4244 that there is a valid backup copy in case there is a power failure 4245 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4246 aligned to an erase sector boundary. 4247 4248 - CONFIG_ENV_SPI_BUS (optional): 4249 - CONFIG_ENV_SPI_CS (optional): 4250 4251 Define the SPI bus and chip select. If not defined they will be 0. 4252 4253 - CONFIG_ENV_SPI_MAX_HZ (optional): 4254 4255 Define the SPI max work clock. If not defined then use 1MHz. 4256 4257 - CONFIG_ENV_SPI_MODE (optional): 4258 4259 Define the SPI work mode. If not defined then use SPI_MODE_3. 4260 4261- CONFIG_ENV_IS_IN_REMOTE: 4262 4263 Define this if you have a remote memory space which you 4264 want to use for the local device's environment. 4265 4266 - CONFIG_ENV_ADDR: 4267 - CONFIG_ENV_SIZE: 4268 4269 These two #defines specify the address and size of the 4270 environment area within the remote memory space. The 4271 local device can get the environment from remote memory 4272 space by SRIO or PCIE links. 4273 4274BE CAREFUL! For some special cases, the local device can not use 4275"saveenv" command. For example, the local device will get the 4276environment stored in a remote NOR flash by SRIO or PCIE link, 4277but it can not erase, write this NOR flash by SRIO or PCIE interface. 4278 4279- CONFIG_ENV_IS_IN_NAND: 4280 4281 Define this if you have a NAND device which you want to use 4282 for the environment. 4283 4284 - CONFIG_ENV_OFFSET: 4285 - CONFIG_ENV_SIZE: 4286 4287 These two #defines specify the offset and size of the environment 4288 area within the first NAND device. CONFIG_ENV_OFFSET must be 4289 aligned to an erase block boundary. 4290 4291 - CONFIG_ENV_OFFSET_REDUND (optional): 4292 4293 This setting describes a second storage area of CONFIG_ENV_SIZE 4294 size used to hold a redundant copy of the environment data, so 4295 that there is a valid backup copy in case there is a power failure 4296 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4297 aligned to an erase block boundary. 4298 4299 - CONFIG_ENV_RANGE (optional): 4300 4301 Specifies the length of the region in which the environment 4302 can be written. This should be a multiple of the NAND device's 4303 block size. Specifying a range with more erase blocks than 4304 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4305 the range to be avoided. 4306 4307 - CONFIG_ENV_OFFSET_OOB (optional): 4308 4309 Enables support for dynamically retrieving the offset of the 4310 environment from block zero's out-of-band data. The 4311 "nand env.oob" command can be used to record this offset. 4312 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4313 using CONFIG_ENV_OFFSET_OOB. 4314 4315- CONFIG_NAND_ENV_DST 4316 4317 Defines address in RAM to which the nand_spl code should copy the 4318 environment. If redundant environment is used, it will be copied to 4319 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4320 4321- CONFIG_ENV_IS_IN_UBI: 4322 4323 Define this if you have an UBI volume that you want to use for the 4324 environment. This has the benefit of wear-leveling the environment 4325 accesses, which is important on NAND. 4326 4327 - CONFIG_ENV_UBI_PART: 4328 4329 Define this to a string that is the mtd partition containing the UBI. 4330 4331 - CONFIG_ENV_UBI_VOLUME: 4332 4333 Define this to the name of the volume that you want to store the 4334 environment in. 4335 4336 - CONFIG_ENV_UBI_VOLUME_REDUND: 4337 4338 Define this to the name of another volume to store a second copy of 4339 the environment in. This will enable redundant environments in UBI. 4340 It is assumed that both volumes are in the same MTD partition. 4341 4342 - CONFIG_UBI_SILENCE_MSG 4343 - CONFIG_UBIFS_SILENCE_MSG 4344 4345 You will probably want to define these to avoid a really noisy system 4346 when storing the env in UBI. 4347 4348- CONFIG_ENV_IS_IN_FAT: 4349 Define this if you want to use the FAT file system for the environment. 4350 4351 - FAT_ENV_INTERFACE: 4352 4353 Define this to a string that is the name of the block device. 4354 4355 - FAT_ENV_DEV_AND_PART: 4356 4357 Define this to a string to specify the partition of the device. It can 4358 be as following: 4359 4360 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4361 - "D:P": device D partition P. Error occurs if device D has no 4362 partition table. 4363 - "D:0": device D. 4364 - "D" or "D:": device D partition 1 if device D has partition 4365 table, or the whole device D if has no partition 4366 table. 4367 - "D:auto": first partition in device D with bootable flag set. 4368 If none, first valid paratition in device D. If no 4369 partition table then means device D. 4370 4371 - FAT_ENV_FILE: 4372 4373 It's a string of the FAT file name. This file use to store the 4374 envrionment. 4375 4376 - CONFIG_FAT_WRITE: 4377 This should be defined. Otherwise it cannot save the envrionment file. 4378 4379- CONFIG_ENV_IS_IN_MMC: 4380 4381 Define this if you have an MMC device which you want to use for the 4382 environment. 4383 4384 - CONFIG_SYS_MMC_ENV_DEV: 4385 4386 Specifies which MMC device the environment is stored in. 4387 4388 - CONFIG_SYS_MMC_ENV_PART (optional): 4389 4390 Specifies which MMC partition the environment is stored in. If not 4391 set, defaults to partition 0, the user area. Common values might be 4392 1 (first MMC boot partition), 2 (second MMC boot partition). 4393 4394 - CONFIG_ENV_OFFSET: 4395 - CONFIG_ENV_SIZE: 4396 4397 These two #defines specify the offset and size of the environment 4398 area within the specified MMC device. 4399 4400 If offset is positive (the usual case), it is treated as relative to 4401 the start of the MMC partition. If offset is negative, it is treated 4402 as relative to the end of the MMC partition. This can be useful if 4403 your board may be fitted with different MMC devices, which have 4404 different sizes for the MMC partitions, and you always want the 4405 environment placed at the very end of the partition, to leave the 4406 maximum possible space before it, to store other data. 4407 4408 These two values are in units of bytes, but must be aligned to an 4409 MMC sector boundary. 4410 4411 - CONFIG_ENV_OFFSET_REDUND (optional): 4412 4413 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4414 hold a redundant copy of the environment data. This provides a 4415 valid backup copy in case the other copy is corrupted, e.g. due 4416 to a power failure during a "saveenv" operation. 4417 4418 This value may also be positive or negative; this is handled in the 4419 same way as CONFIG_ENV_OFFSET. 4420 4421 This value is also in units of bytes, but must also be aligned to 4422 an MMC sector boundary. 4423 4424 - CONFIG_ENV_SIZE_REDUND (optional): 4425 4426 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4427 set. If this value is set, it must be set to the same value as 4428 CONFIG_ENV_SIZE. 4429 4430- CONFIG_SYS_SPI_INIT_OFFSET 4431 4432 Defines offset to the initial SPI buffer area in DPRAM. The 4433 area is used at an early stage (ROM part) if the environment 4434 is configured to reside in the SPI EEPROM: We need a 520 byte 4435 scratch DPRAM area. It is used between the two initialization 4436 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4437 to be a good choice since it makes it far enough from the 4438 start of the data area as well as from the stack pointer. 4439 4440Please note that the environment is read-only until the monitor 4441has been relocated to RAM and a RAM copy of the environment has been 4442created; also, when using EEPROM you will have to use getenv_f() 4443until then to read environment variables. 4444 4445The environment is protected by a CRC32 checksum. Before the monitor 4446is relocated into RAM, as a result of a bad CRC you will be working 4447with the compiled-in default environment - *silently*!!! [This is 4448necessary, because the first environment variable we need is the 4449"baudrate" setting for the console - if we have a bad CRC, we don't 4450have any device yet where we could complain.] 4451 4452Note: once the monitor has been relocated, then it will complain if 4453the default environment is used; a new CRC is computed as soon as you 4454use the "saveenv" command to store a valid environment. 4455 4456- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4457 Echo the inverted Ethernet link state to the fault LED. 4458 4459 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4460 also needs to be defined. 4461 4462- CONFIG_SYS_FAULT_MII_ADDR: 4463 MII address of the PHY to check for the Ethernet link state. 4464 4465- CONFIG_NS16550_MIN_FUNCTIONS: 4466 Define this if you desire to only have use of the NS16550_init 4467 and NS16550_putc functions for the serial driver located at 4468 drivers/serial/ns16550.c. This option is useful for saving 4469 space for already greatly restricted images, including but not 4470 limited to NAND_SPL configurations. 4471 4472- CONFIG_DISPLAY_BOARDINFO 4473 Display information about the board that U-Boot is running on 4474 when U-Boot starts up. The board function checkboard() is called 4475 to do this. 4476 4477- CONFIG_DISPLAY_BOARDINFO_LATE 4478 Similar to the previous option, but display this information 4479 later, once stdio is running and output goes to the LCD, if 4480 present. 4481 4482- CONFIG_BOARD_SIZE_LIMIT: 4483 Maximum size of the U-Boot image. When defined, the 4484 build system checks that the actual size does not 4485 exceed it. 4486 4487Low Level (hardware related) configuration options: 4488--------------------------------------------------- 4489 4490- CONFIG_SYS_CACHELINE_SIZE: 4491 Cache Line Size of the CPU. 4492 4493- CONFIG_SYS_DEFAULT_IMMR: 4494 Default address of the IMMR after system reset. 4495 4496 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4497 and RPXsuper) to be able to adjust the position of 4498 the IMMR register after a reset. 4499 4500- CONFIG_SYS_CCSRBAR_DEFAULT: 4501 Default (power-on reset) physical address of CCSR on Freescale 4502 PowerPC SOCs. 4503 4504- CONFIG_SYS_CCSRBAR: 4505 Virtual address of CCSR. On a 32-bit build, this is typically 4506 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4507 4508 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4509 for cross-platform code that uses that macro instead. 4510 4511- CONFIG_SYS_CCSRBAR_PHYS: 4512 Physical address of CCSR. CCSR can be relocated to a new 4513 physical address, if desired. In this case, this macro should 4514 be set to that address. Otherwise, it should be set to the 4515 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4516 is typically relocated on 36-bit builds. It is recommended 4517 that this macro be defined via the _HIGH and _LOW macros: 4518 4519 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4520 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4521 4522- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4523 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4524 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4525 used in assembly code, so it must not contain typecasts or 4526 integer size suffixes (e.g. "ULL"). 4527 4528- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4529 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4530 used in assembly code, so it must not contain typecasts or 4531 integer size suffixes (e.g. "ULL"). 4532 4533- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4534 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4535 forced to a value that ensures that CCSR is not relocated. 4536 4537- Floppy Disk Support: 4538 CONFIG_SYS_FDC_DRIVE_NUMBER 4539 4540 the default drive number (default value 0) 4541 4542 CONFIG_SYS_ISA_IO_STRIDE 4543 4544 defines the spacing between FDC chipset registers 4545 (default value 1) 4546 4547 CONFIG_SYS_ISA_IO_OFFSET 4548 4549 defines the offset of register from address. It 4550 depends on which part of the data bus is connected to 4551 the FDC chipset. (default value 0) 4552 4553 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4554 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4555 default value. 4556 4557 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4558 fdc_hw_init() is called at the beginning of the FDC 4559 setup. fdc_hw_init() must be provided by the board 4560 source code. It is used to make hardware dependant 4561 initializations. 4562 4563- CONFIG_IDE_AHB: 4564 Most IDE controllers were designed to be connected with PCI 4565 interface. Only few of them were designed for AHB interface. 4566 When software is doing ATA command and data transfer to 4567 IDE devices through IDE-AHB controller, some additional 4568 registers accessing to these kind of IDE-AHB controller 4569 is requierd. 4570 4571- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4572 DO NOT CHANGE unless you know exactly what you're 4573 doing! (11-4) [MPC8xx/82xx systems only] 4574 4575- CONFIG_SYS_INIT_RAM_ADDR: 4576 4577 Start address of memory area that can be used for 4578 initial data and stack; please note that this must be 4579 writable memory that is working WITHOUT special 4580 initialization, i. e. you CANNOT use normal RAM which 4581 will become available only after programming the 4582 memory controller and running certain initialization 4583 sequences. 4584 4585 U-Boot uses the following memory types: 4586 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4587 - MPC824X: data cache 4588 - PPC4xx: data cache 4589 4590- CONFIG_SYS_GBL_DATA_OFFSET: 4591 4592 Offset of the initial data structure in the memory 4593 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4594 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4595 data is located at the end of the available space 4596 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4597 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4598 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4599 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4600 4601 Note: 4602 On the MPC824X (or other systems that use the data 4603 cache for initial memory) the address chosen for 4604 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4605 point to an otherwise UNUSED address space between 4606 the top of RAM and the start of the PCI space. 4607 4608- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4609 4610- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4611 4612- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4613 4614- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4615 4616- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4617 4618- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4619 4620- CONFIG_SYS_OR_TIMING_SDRAM: 4621 SDRAM timing 4622 4623- CONFIG_SYS_MAMR_PTA: 4624 periodic timer for refresh 4625 4626- CONFIG_SYS_DER: Debug Event Register (37-47) 4627 4628- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4629 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4630 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4631 CONFIG_SYS_BR1_PRELIM: 4632 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4633 4634- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4635 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4636 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4637 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4638 4639- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4640 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4641 Machine Mode Register and Memory Periodic Timer 4642 Prescaler definitions (SDRAM timing) 4643 4644- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4645 enable I2C microcode relocation patch (MPC8xx); 4646 define relocation offset in DPRAM [DSP2] 4647 4648- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4649 enable SMC microcode relocation patch (MPC8xx); 4650 define relocation offset in DPRAM [SMC1] 4651 4652- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4653 enable SPI microcode relocation patch (MPC8xx); 4654 define relocation offset in DPRAM [SCC4] 4655 4656- CONFIG_SYS_USE_OSCCLK: 4657 Use OSCM clock mode on MBX8xx board. Be careful, 4658 wrong setting might damage your board. Read 4659 doc/README.MBX before setting this variable! 4660 4661- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4662 Offset of the bootmode word in DPRAM used by post 4663 (Power On Self Tests). This definition overrides 4664 #define'd default value in commproc.h resp. 4665 cpm_8260.h. 4666 4667- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4668 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4669 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4670 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4671 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4672 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4673 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4674 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4675 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4676 4677- CONFIG_PCI_DISABLE_PCIE: 4678 Disable PCI-Express on systems where it is supported but not 4679 required. 4680 4681- CONFIG_PCI_ENUM_ONLY 4682 Only scan through and get the devices on the busses. 4683 Don't do any setup work, presumably because someone or 4684 something has already done it, and we don't need to do it 4685 a second time. Useful for platforms that are pre-booted 4686 by coreboot or similar. 4687 4688- CONFIG_PCI_INDIRECT_BRIDGE: 4689 Enable support for indirect PCI bridges. 4690 4691- CONFIG_SYS_SRIO: 4692 Chip has SRIO or not 4693 4694- CONFIG_SRIO1: 4695 Board has SRIO 1 port available 4696 4697- CONFIG_SRIO2: 4698 Board has SRIO 2 port available 4699 4700- CONFIG_SRIO_PCIE_BOOT_MASTER 4701 Board can support master function for Boot from SRIO and PCIE 4702 4703- CONFIG_SYS_SRIOn_MEM_VIRT: 4704 Virtual Address of SRIO port 'n' memory region 4705 4706- CONFIG_SYS_SRIOn_MEM_PHYS: 4707 Physical Address of SRIO port 'n' memory region 4708 4709- CONFIG_SYS_SRIOn_MEM_SIZE: 4710 Size of SRIO port 'n' memory region 4711 4712- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4713 Defined to tell the NAND controller that the NAND chip is using 4714 a 16 bit bus. 4715 Not all NAND drivers use this symbol. 4716 Example of drivers that use it: 4717 - drivers/mtd/nand/ndfc.c 4718 - drivers/mtd/nand/mxc_nand.c 4719 4720- CONFIG_SYS_NDFC_EBC0_CFG 4721 Sets the EBC0_CFG register for the NDFC. If not defined 4722 a default value will be used. 4723 4724- CONFIG_SPD_EEPROM 4725 Get DDR timing information from an I2C EEPROM. Common 4726 with pluggable memory modules such as SODIMMs 4727 4728 SPD_EEPROM_ADDRESS 4729 I2C address of the SPD EEPROM 4730 4731- CONFIG_SYS_SPD_BUS_NUM 4732 If SPD EEPROM is on an I2C bus other than the first 4733 one, specify here. Note that the value must resolve 4734 to something your driver can deal with. 4735 4736- CONFIG_SYS_DDR_RAW_TIMING 4737 Get DDR timing information from other than SPD. Common with 4738 soldered DDR chips onboard without SPD. DDR raw timing 4739 parameters are extracted from datasheet and hard-coded into 4740 header files or board specific files. 4741 4742- CONFIG_FSL_DDR_INTERACTIVE 4743 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4744 4745- CONFIG_SYS_83XX_DDR_USES_CS0 4746 Only for 83xx systems. If specified, then DDR should 4747 be configured using CS0 and CS1 instead of CS2 and CS3. 4748 4749- CONFIG_ETHER_ON_FEC[12] 4750 Define to enable FEC[12] on a 8xx series processor. 4751 4752- CONFIG_FEC[12]_PHY 4753 Define to the hardcoded PHY address which corresponds 4754 to the given FEC; i. e. 4755 #define CONFIG_FEC1_PHY 4 4756 means that the PHY with address 4 is connected to FEC1 4757 4758 When set to -1, means to probe for first available. 4759 4760- CONFIG_FEC[12]_PHY_NORXERR 4761 The PHY does not have a RXERR line (RMII only). 4762 (so program the FEC to ignore it). 4763 4764- CONFIG_RMII 4765 Enable RMII mode for all FECs. 4766 Note that this is a global option, we can't 4767 have one FEC in standard MII mode and another in RMII mode. 4768 4769- CONFIG_CRC32_VERIFY 4770 Add a verify option to the crc32 command. 4771 The syntax is: 4772 4773 => crc32 -v <address> <count> <crc32> 4774 4775 Where address/count indicate a memory area 4776 and crc32 is the correct crc32 which the 4777 area should have. 4778 4779- CONFIG_LOOPW 4780 Add the "loopw" memory command. This only takes effect if 4781 the memory commands are activated globally (CONFIG_CMD_MEM). 4782 4783- CONFIG_MX_CYCLIC 4784 Add the "mdc" and "mwc" memory commands. These are cyclic 4785 "md/mw" commands. 4786 Examples: 4787 4788 => mdc.b 10 4 500 4789 This command will print 4 bytes (10,11,12,13) each 500 ms. 4790 4791 => mwc.l 100 12345678 10 4792 This command will write 12345678 to address 100 all 10 ms. 4793 4794 This only takes effect if the memory commands are activated 4795 globally (CONFIG_CMD_MEM). 4796 4797- CONFIG_SKIP_LOWLEVEL_INIT 4798 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4799 low level initializations (like setting up the memory 4800 controller) are omitted and/or U-Boot does not 4801 relocate itself into RAM. 4802 4803 Normally this variable MUST NOT be defined. The only 4804 exception is when U-Boot is loaded (to RAM) by some 4805 other boot loader or by a debugger which performs 4806 these initializations itself. 4807 4808- CONFIG_SPL_BUILD 4809 Modifies the behaviour of start.S when compiling a loader 4810 that is executed before the actual U-Boot. E.g. when 4811 compiling a NAND SPL. 4812 4813- CONFIG_TPL_BUILD 4814 Modifies the behaviour of start.S when compiling a loader 4815 that is executed after the SPL and before the actual U-Boot. 4816 It is loaded by the SPL. 4817 4818- CONFIG_SYS_MPC85XX_NO_RESETVEC 4819 Only for 85xx systems. If this variable is specified, the section 4820 .resetvec is not kept and the section .bootpg is placed in the 4821 previous 4k of the .text section. 4822 4823- CONFIG_ARCH_MAP_SYSMEM 4824 Generally U-Boot (and in particular the md command) uses 4825 effective address. It is therefore not necessary to regard 4826 U-Boot address as virtual addresses that need to be translated 4827 to physical addresses. However, sandbox requires this, since 4828 it maintains its own little RAM buffer which contains all 4829 addressable memory. This option causes some memory accesses 4830 to be mapped through map_sysmem() / unmap_sysmem(). 4831 4832- CONFIG_USE_ARCH_MEMCPY 4833 CONFIG_USE_ARCH_MEMSET 4834 If these options are used a optimized version of memcpy/memset will 4835 be used if available. These functions may be faster under some 4836 conditions but may increase the binary size. 4837 4838- CONFIG_X86_RESET_VECTOR 4839 If defined, the x86 reset vector code is included. This is not 4840 needed when U-Boot is running from Coreboot. 4841 4842- CONFIG_SYS_MPUCLK 4843 Defines the MPU clock speed (in MHz). 4844 4845 NOTE : currently only supported on AM335x platforms. 4846 4847- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4848 Enables the RTC32K OSC on AM33xx based plattforms 4849 4850- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4851 Option to disable subpage write in NAND driver 4852 driver that uses this: 4853 drivers/mtd/nand/davinci_nand.c 4854 4855Freescale QE/FMAN Firmware Support: 4856----------------------------------- 4857 4858The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4859loading of "firmware", which is encoded in the QE firmware binary format. 4860This firmware often needs to be loaded during U-Boot booting, so macros 4861are used to identify the storage device (NOR flash, SPI, etc) and the address 4862within that device. 4863 4864- CONFIG_SYS_FMAN_FW_ADDR 4865 The address in the storage device where the FMAN microcode is located. The 4866 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4867 is also specified. 4868 4869- CONFIG_SYS_QE_FW_ADDR 4870 The address in the storage device where the QE microcode is located. The 4871 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4872 is also specified. 4873 4874- CONFIG_SYS_QE_FMAN_FW_LENGTH 4875 The maximum possible size of the firmware. The firmware binary format 4876 has a field that specifies the actual size of the firmware, but it 4877 might not be possible to read any part of the firmware unless some 4878 local storage is allocated to hold the entire firmware first. 4879 4880- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4881 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4882 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4883 virtual address in NOR flash. 4884 4885- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4886 Specifies that QE/FMAN firmware is located in NAND flash. 4887 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4888 4889- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4890 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4891 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4892 4893- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 4894 Specifies that QE/FMAN firmware is located on the primary SPI 4895 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4896 4897- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4898 Specifies that QE/FMAN firmware is located in the remote (master) 4899 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4900 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4901 window->master inbound window->master LAW->the ucode address in 4902 master's memory space. 4903 4904Freescale Layerscape Management Complex Firmware Support: 4905--------------------------------------------------------- 4906The Freescale Layerscape Management Complex (MC) supports the loading of 4907"firmware". 4908This firmware often needs to be loaded during U-Boot booting, so macros 4909are used to identify the storage device (NOR flash, SPI, etc) and the address 4910within that device. 4911 4912- CONFIG_FSL_MC_ENET 4913 Enable the MC driver for Layerscape SoCs. 4914 4915- CONFIG_SYS_LS_MC_FW_ADDR 4916 The address in the storage device where the firmware is located. The 4917 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro 4918 is also specified. 4919 4920- CONFIG_SYS_LS_MC_FW_LENGTH 4921 The maximum possible size of the firmware. The firmware binary format 4922 has a field that specifies the actual size of the firmware, but it 4923 might not be possible to read any part of the firmware unless some 4924 local storage is allocated to hold the entire firmware first. 4925 4926- CONFIG_SYS_LS_MC_FW_IN_NOR 4927 Specifies that MC firmware is located in NOR flash, mapped as 4928 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the 4929 virtual address in NOR flash. 4930 4931Building the Software: 4932====================== 4933 4934Building U-Boot has been tested in several native build environments 4935and in many different cross environments. Of course we cannot support 4936all possibly existing versions of cross development tools in all 4937(potentially obsolete) versions. In case of tool chain problems we 4938recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4939which is extensively used to build and test U-Boot. 4940 4941If you are not using a native environment, it is assumed that you 4942have GNU cross compiling tools available in your path. In this case, 4943you must set the environment variable CROSS_COMPILE in your shell. 4944Note that no changes to the Makefile or any other source files are 4945necessary. For example using the ELDK on a 4xx CPU, please enter: 4946 4947 $ CROSS_COMPILE=ppc_4xx- 4948 $ export CROSS_COMPILE 4949 4950Note: If you wish to generate Windows versions of the utilities in 4951 the tools directory you can use the MinGW toolchain 4952 (http://www.mingw.org). Set your HOST tools to the MinGW 4953 toolchain and execute 'make tools'. For example: 4954 4955 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4956 4957 Binaries such as tools/mkimage.exe will be created which can 4958 be executed on computers running Windows. 4959 4960U-Boot is intended to be simple to build. After installing the 4961sources you must configure U-Boot for one specific board type. This 4962is done by typing: 4963 4964 make NAME_defconfig 4965 4966where "NAME_defconfig" is the name of one of the existing configu- 4967rations; see boards.cfg for supported names. 4968 4969Note: for some board special configuration names may exist; check if 4970 additional information is available from the board vendor; for 4971 instance, the TQM823L systems are available without (standard) 4972 or with LCD support. You can select such additional "features" 4973 when choosing the configuration, i. e. 4974 4975 make TQM823L_defconfig 4976 - will configure for a plain TQM823L, i. e. no LCD support 4977 4978 make TQM823L_LCD_defconfig 4979 - will configure for a TQM823L with U-Boot console on LCD 4980 4981 etc. 4982 4983 4984Finally, type "make all", and you should get some working U-Boot 4985images ready for download to / installation on your system: 4986 4987- "u-boot.bin" is a raw binary image 4988- "u-boot" is an image in ELF binary format 4989- "u-boot.srec" is in Motorola S-Record format 4990 4991By default the build is performed locally and the objects are saved 4992in the source directory. One of the two methods can be used to change 4993this behavior and build U-Boot to some external directory: 4994 49951. Add O= to the make command line invocations: 4996 4997 make O=/tmp/build distclean 4998 make O=/tmp/build NAME_defconfig 4999 make O=/tmp/build all 5000 50012. Set environment variable BUILD_DIR to point to the desired location: 5002 5003 export BUILD_DIR=/tmp/build 5004 make distclean 5005 make NAME_defconfig 5006 make all 5007 5008Note that the command line "O=" setting overrides the BUILD_DIR environment 5009variable. 5010 5011 5012Please be aware that the Makefiles assume you are using GNU make, so 5013for instance on NetBSD you might need to use "gmake" instead of 5014native "make". 5015 5016 5017If the system board that you have is not listed, then you will need 5018to port U-Boot to your hardware platform. To do this, follow these 5019steps: 5020 50211. Add a new configuration option for your board to the toplevel 5022 "boards.cfg" file, using the existing entries as examples. 5023 Follow the instructions there to keep the boards in order. 50242. Create a new directory to hold your board specific code. Add any 5025 files you need. In your board directory, you will need at least 5026 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 50273. Create a new configuration file "include/configs/<board>.h" for 5028 your board 50293. If you're porting U-Boot to a new CPU, then also create a new 5030 directory to hold your CPU specific code. Add any files you need. 50314. Run "make <board>_defconfig" with your new name. 50325. Type "make", and you should get a working "u-boot.srec" file 5033 to be installed on your target system. 50346. Debug and solve any problems that might arise. 5035 [Of course, this last step is much harder than it sounds.] 5036 5037 5038Testing of U-Boot Modifications, Ports to New Hardware, etc.: 5039============================================================== 5040 5041If you have modified U-Boot sources (for instance added a new board 5042or support for new devices, a new CPU, etc.) you are expected to 5043provide feedback to the other developers. The feedback normally takes 5044the form of a "patch", i. e. a context diff against a certain (latest 5045official or latest in the git repository) version of U-Boot sources. 5046 5047But before you submit such a patch, please verify that your modifi- 5048cation did not break existing code. At least make sure that *ALL* of 5049the supported boards compile WITHOUT ANY compiler warnings. To do so, 5050just run the "MAKEALL" script, which will configure and build U-Boot 5051for ALL supported system. Be warned, this will take a while. You can 5052select which (cross) compiler to use by passing a `CROSS_COMPILE' 5053environment variable to the script, i. e. to use the ELDK cross tools 5054you can type 5055 5056 CROSS_COMPILE=ppc_8xx- MAKEALL 5057 5058or to build on a native PowerPC system you can type 5059 5060 CROSS_COMPILE=' ' MAKEALL 5061 5062When using the MAKEALL script, the default behaviour is to build 5063U-Boot in the source directory. This location can be changed by 5064setting the BUILD_DIR environment variable. Also, for each target 5065built, the MAKEALL script saves two log files (<target>.ERR and 5066<target>.MAKEALL) in the <source dir>/LOG directory. This default 5067location can be changed by setting the MAKEALL_LOGDIR environment 5068variable. For example: 5069 5070 export BUILD_DIR=/tmp/build 5071 export MAKEALL_LOGDIR=/tmp/log 5072 CROSS_COMPILE=ppc_8xx- MAKEALL 5073 5074With the above settings build objects are saved in the /tmp/build, 5075log files are saved in the /tmp/log and the source tree remains clean 5076during the whole build process. 5077 5078 5079See also "U-Boot Porting Guide" below. 5080 5081 5082Monitor Commands - Overview: 5083============================ 5084 5085go - start application at address 'addr' 5086run - run commands in an environment variable 5087bootm - boot application image from memory 5088bootp - boot image via network using BootP/TFTP protocol 5089bootz - boot zImage from memory 5090tftpboot- boot image via network using TFTP protocol 5091 and env variables "ipaddr" and "serverip" 5092 (and eventually "gatewayip") 5093tftpput - upload a file via network using TFTP protocol 5094rarpboot- boot image via network using RARP/TFTP protocol 5095diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 5096loads - load S-Record file over serial line 5097loadb - load binary file over serial line (kermit mode) 5098md - memory display 5099mm - memory modify (auto-incrementing) 5100nm - memory modify (constant address) 5101mw - memory write (fill) 5102cp - memory copy 5103cmp - memory compare 5104crc32 - checksum calculation 5105i2c - I2C sub-system 5106sspi - SPI utility commands 5107base - print or set address offset 5108printenv- print environment variables 5109setenv - set environment variables 5110saveenv - save environment variables to persistent storage 5111protect - enable or disable FLASH write protection 5112erase - erase FLASH memory 5113flinfo - print FLASH memory information 5114nand - NAND memory operations (see doc/README.nand) 5115bdinfo - print Board Info structure 5116iminfo - print header information for application image 5117coninfo - print console devices and informations 5118ide - IDE sub-system 5119loop - infinite loop on address range 5120loopw - infinite write loop on address range 5121mtest - simple RAM test 5122icache - enable or disable instruction cache 5123dcache - enable or disable data cache 5124reset - Perform RESET of the CPU 5125echo - echo args to console 5126version - print monitor version 5127help - print online help 5128? - alias for 'help' 5129 5130 5131Monitor Commands - Detailed Description: 5132======================================== 5133 5134TODO. 5135 5136For now: just type "help <command>". 5137 5138 5139Environment Variables: 5140====================== 5141 5142U-Boot supports user configuration using Environment Variables which 5143can be made persistent by saving to Flash memory. 5144 5145Environment Variables are set using "setenv", printed using 5146"printenv", and saved to Flash using "saveenv". Using "setenv" 5147without a value can be used to delete a variable from the 5148environment. As long as you don't save the environment you are 5149working with an in-memory copy. In case the Flash area containing the 5150environment is erased by accident, a default environment is provided. 5151 5152Some configuration options can be set using Environment Variables. 5153 5154List of environment variables (most likely not complete): 5155 5156 baudrate - see CONFIG_BAUDRATE 5157 5158 bootdelay - see CONFIG_BOOTDELAY 5159 5160 bootcmd - see CONFIG_BOOTCOMMAND 5161 5162 bootargs - Boot arguments when booting an RTOS image 5163 5164 bootfile - Name of the image to load with TFTP 5165 5166 bootm_low - Memory range available for image processing in the bootm 5167 command can be restricted. This variable is given as 5168 a hexadecimal number and defines lowest address allowed 5169 for use by the bootm command. See also "bootm_size" 5170 environment variable. Address defined by "bootm_low" is 5171 also the base of the initial memory mapping for the Linux 5172 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 5173 bootm_mapsize. 5174 5175 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 5176 This variable is given as a hexadecimal number and it 5177 defines the size of the memory region starting at base 5178 address bootm_low that is accessible by the Linux kernel 5179 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 5180 as the default value if it is defined, and bootm_size is 5181 used otherwise. 5182 5183 bootm_size - Memory range available for image processing in the bootm 5184 command can be restricted. This variable is given as 5185 a hexadecimal number and defines the size of the region 5186 allowed for use by the bootm command. See also "bootm_low" 5187 environment variable. 5188 5189 updatefile - Location of the software update file on a TFTP server, used 5190 by the automatic software update feature. Please refer to 5191 documentation in doc/README.update for more details. 5192 5193 autoload - if set to "no" (any string beginning with 'n'), 5194 "bootp" will just load perform a lookup of the 5195 configuration from the BOOTP server, but not try to 5196 load any image using TFTP 5197 5198 autostart - if set to "yes", an image loaded using the "bootp", 5199 "rarpboot", "tftpboot" or "diskboot" commands will 5200 be automatically started (by internally calling 5201 "bootm") 5202 5203 If set to "no", a standalone image passed to the 5204 "bootm" command will be copied to the load address 5205 (and eventually uncompressed), but NOT be started. 5206 This can be used to load and uncompress arbitrary 5207 data. 5208 5209 fdt_high - if set this restricts the maximum address that the 5210 flattened device tree will be copied into upon boot. 5211 For example, if you have a system with 1 GB memory 5212 at physical address 0x10000000, while Linux kernel 5213 only recognizes the first 704 MB as low memory, you 5214 may need to set fdt_high as 0x3C000000 to have the 5215 device tree blob be copied to the maximum address 5216 of the 704 MB low memory, so that Linux kernel can 5217 access it during the boot procedure. 5218 5219 If this is set to the special value 0xFFFFFFFF then 5220 the fdt will not be copied at all on boot. For this 5221 to work it must reside in writable memory, have 5222 sufficient padding on the end of it for u-boot to 5223 add the information it needs into it, and the memory 5224 must be accessible by the kernel. 5225 5226 fdtcontroladdr- if set this is the address of the control flattened 5227 device tree used by U-Boot when CONFIG_OF_CONTROL is 5228 defined. 5229 5230 i2cfast - (PPC405GP|PPC405EP only) 5231 if set to 'y' configures Linux I2C driver for fast 5232 mode (400kHZ). This environment variable is used in 5233 initialization code. So, for changes to be effective 5234 it must be saved and board must be reset. 5235 5236 initrd_high - restrict positioning of initrd images: 5237 If this variable is not set, initrd images will be 5238 copied to the highest possible address in RAM; this 5239 is usually what you want since it allows for 5240 maximum initrd size. If for some reason you want to 5241 make sure that the initrd image is loaded below the 5242 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 5243 variable to a value of "no" or "off" or "0". 5244 Alternatively, you can set it to a maximum upper 5245 address to use (U-Boot will still check that it 5246 does not overwrite the U-Boot stack and data). 5247 5248 For instance, when you have a system with 16 MB 5249 RAM, and want to reserve 4 MB from use by Linux, 5250 you can do this by adding "mem=12M" to the value of 5251 the "bootargs" variable. However, now you must make 5252 sure that the initrd image is placed in the first 5253 12 MB as well - this can be done with 5254 5255 setenv initrd_high 00c00000 5256 5257 If you set initrd_high to 0xFFFFFFFF, this is an 5258 indication to U-Boot that all addresses are legal 5259 for the Linux kernel, including addresses in flash 5260 memory. In this case U-Boot will NOT COPY the 5261 ramdisk at all. This may be useful to reduce the 5262 boot time on your system, but requires that this 5263 feature is supported by your Linux kernel. 5264 5265 ipaddr - IP address; needed for tftpboot command 5266 5267 loadaddr - Default load address for commands like "bootp", 5268 "rarpboot", "tftpboot", "loadb" or "diskboot" 5269 5270 loads_echo - see CONFIG_LOADS_ECHO 5271 5272 serverip - TFTP server IP address; needed for tftpboot command 5273 5274 bootretry - see CONFIG_BOOT_RETRY_TIME 5275 5276 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 5277 5278 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 5279 5280 ethprime - controls which interface is used first. 5281 5282 ethact - controls which interface is currently active. 5283 For example you can do the following 5284 5285 => setenv ethact FEC 5286 => ping 192.168.0.1 # traffic sent on FEC 5287 => setenv ethact SCC 5288 => ping 10.0.0.1 # traffic sent on SCC 5289 5290 ethrotate - When set to "no" U-Boot does not go through all 5291 available network interfaces. 5292 It just stays at the currently selected interface. 5293 5294 netretry - When set to "no" each network operation will 5295 either succeed or fail without retrying. 5296 When set to "once" the network operation will 5297 fail when all the available network interfaces 5298 are tried once without success. 5299 Useful on scripts which control the retry operation 5300 themselves. 5301 5302 npe_ucode - set load address for the NPE microcode 5303 5304 silent_linux - If set then linux will be told to boot silently, by 5305 changing the console to be empty. If "yes" it will be 5306 made silent. If "no" it will not be made silent. If 5307 unset, then it will be made silent if the U-Boot console 5308 is silent. 5309 5310 tftpsrcport - If this is set, the value is used for TFTP's 5311 UDP source port. 5312 5313 tftpdstport - If this is set, the value is used for TFTP's UDP 5314 destination port instead of the Well Know Port 69. 5315 5316 tftpblocksize - Block size to use for TFTP transfers; if not set, 5317 we use the TFTP server's default block size 5318 5319 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5320 seconds, minimum value is 1000 = 1 second). Defines 5321 when a packet is considered to be lost so it has to 5322 be retransmitted. The default is 5000 = 5 seconds. 5323 Lowering this value may make downloads succeed 5324 faster in networks with high packet loss rates or 5325 with unreliable TFTP servers. 5326 5327 vlan - When set to a value < 4095 the traffic over 5328 Ethernet is encapsulated/received over 802.1q 5329 VLAN tagged frames. 5330 5331The following image location variables contain the location of images 5332used in booting. The "Image" column gives the role of the image and is 5333not an environment variable name. The other columns are environment 5334variable names. "File Name" gives the name of the file on a TFTP 5335server, "RAM Address" gives the location in RAM the image will be 5336loaded to, and "Flash Location" gives the image's address in NOR 5337flash or offset in NAND flash. 5338 5339*Note* - these variables don't have to be defined for all boards, some 5340boards currenlty use other variables for these purposes, and some 5341boards use these variables for other purposes. 5342 5343Image File Name RAM Address Flash Location 5344----- --------- ----------- -------------- 5345u-boot u-boot u-boot_addr_r u-boot_addr 5346Linux kernel bootfile kernel_addr_r kernel_addr 5347device tree blob fdtfile fdt_addr_r fdt_addr 5348ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5349 5350The following environment variables may be used and automatically 5351updated by the network boot commands ("bootp" and "rarpboot"), 5352depending the information provided by your boot server: 5353 5354 bootfile - see above 5355 dnsip - IP address of your Domain Name Server 5356 dnsip2 - IP address of your secondary Domain Name Server 5357 gatewayip - IP address of the Gateway (Router) to use 5358 hostname - Target hostname 5359 ipaddr - see above 5360 netmask - Subnet Mask 5361 rootpath - Pathname of the root filesystem on the NFS server 5362 serverip - see above 5363 5364 5365There are two special Environment Variables: 5366 5367 serial# - contains hardware identification information such 5368 as type string and/or serial number 5369 ethaddr - Ethernet address 5370 5371These variables can be set only once (usually during manufacturing of 5372the board). U-Boot refuses to delete or overwrite these variables 5373once they have been set once. 5374 5375 5376Further special Environment Variables: 5377 5378 ver - Contains the U-Boot version string as printed 5379 with the "version" command. This variable is 5380 readonly (see CONFIG_VERSION_VARIABLE). 5381 5382 5383Please note that changes to some configuration parameters may take 5384only effect after the next boot (yes, that's just like Windoze :-). 5385 5386 5387Callback functions for environment variables: 5388--------------------------------------------- 5389 5390For some environment variables, the behavior of u-boot needs to change 5391when their values are changed. This functionailty allows functions to 5392be associated with arbitrary variables. On creation, overwrite, or 5393deletion, the callback will provide the opportunity for some side 5394effect to happen or for the change to be rejected. 5395 5396The callbacks are named and associated with a function using the 5397U_BOOT_ENV_CALLBACK macro in your board or driver code. 5398 5399These callbacks are associated with variables in one of two ways. The 5400static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5401in the board configuration to a string that defines a list of 5402associations. The list must be in the following format: 5403 5404 entry = variable_name[:callback_name] 5405 list = entry[,list] 5406 5407If the callback name is not specified, then the callback is deleted. 5408Spaces are also allowed anywhere in the list. 5409 5410Callbacks can also be associated by defining the ".callbacks" variable 5411with the same list format above. Any association in ".callbacks" will 5412override any association in the static list. You can define 5413CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5414".callbacks" envirnoment variable in the default or embedded environment. 5415 5416 5417Command Line Parsing: 5418===================== 5419 5420There are two different command line parsers available with U-Boot: 5421the old "simple" one, and the much more powerful "hush" shell: 5422 5423Old, simple command line parser: 5424-------------------------------- 5425 5426- supports environment variables (through setenv / saveenv commands) 5427- several commands on one line, separated by ';' 5428- variable substitution using "... ${name} ..." syntax 5429- special characters ('$', ';') can be escaped by prefixing with '\', 5430 for example: 5431 setenv bootcmd bootm \${address} 5432- You can also escape text by enclosing in single apostrophes, for example: 5433 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5434 5435Hush shell: 5436----------- 5437 5438- similar to Bourne shell, with control structures like 5439 if...then...else...fi, for...do...done; while...do...done, 5440 until...do...done, ... 5441- supports environment ("global") variables (through setenv / saveenv 5442 commands) and local shell variables (through standard shell syntax 5443 "name=value"); only environment variables can be used with "run" 5444 command 5445 5446General rules: 5447-------------- 5448 5449(1) If a command line (or an environment variable executed by a "run" 5450 command) contains several commands separated by semicolon, and 5451 one of these commands fails, then the remaining commands will be 5452 executed anyway. 5453 5454(2) If you execute several variables with one call to run (i. e. 5455 calling run with a list of variables as arguments), any failing 5456 command will cause "run" to terminate, i. e. the remaining 5457 variables are not executed. 5458 5459Note for Redundant Ethernet Interfaces: 5460======================================= 5461 5462Some boards come with redundant Ethernet interfaces; U-Boot supports 5463such configurations and is capable of automatic selection of a 5464"working" interface when needed. MAC assignment works as follows: 5465 5466Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5467MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5468"eth1addr" (=>eth1), "eth2addr", ... 5469 5470If the network interface stores some valid MAC address (for instance 5471in SROM), this is used as default address if there is NO correspon- 5472ding setting in the environment; if the corresponding environment 5473variable is set, this overrides the settings in the card; that means: 5474 5475o If the SROM has a valid MAC address, and there is no address in the 5476 environment, the SROM's address is used. 5477 5478o If there is no valid address in the SROM, and a definition in the 5479 environment exists, then the value from the environment variable is 5480 used. 5481 5482o If both the SROM and the environment contain a MAC address, and 5483 both addresses are the same, this MAC address is used. 5484 5485o If both the SROM and the environment contain a MAC address, and the 5486 addresses differ, the value from the environment is used and a 5487 warning is printed. 5488 5489o If neither SROM nor the environment contain a MAC address, an error 5490 is raised. 5491 5492If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5493will be programmed into hardware as part of the initialization process. This 5494may be skipped by setting the appropriate 'ethmacskip' environment variable. 5495The naming convention is as follows: 5496"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5497 5498Image Formats: 5499============== 5500 5501U-Boot is capable of booting (and performing other auxiliary operations on) 5502images in two formats: 5503 5504New uImage format (FIT) 5505----------------------- 5506 5507Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5508to Flattened Device Tree). It allows the use of images with multiple 5509components (several kernels, ramdisks, etc.), with contents protected by 5510SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5511 5512 5513Old uImage format 5514----------------- 5515 5516Old image format is based on binary files which can be basically anything, 5517preceded by a special header; see the definitions in include/image.h for 5518details; basically, the header defines the following image properties: 5519 5520* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5521 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5522 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5523 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5524 INTEGRITY). 5525* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5526 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5527 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5528* Compression Type (uncompressed, gzip, bzip2) 5529* Load Address 5530* Entry Point 5531* Image Name 5532* Image Timestamp 5533 5534The header is marked by a special Magic Number, and both the header 5535and the data portions of the image are secured against corruption by 5536CRC32 checksums. 5537 5538 5539Linux Support: 5540============== 5541 5542Although U-Boot should support any OS or standalone application 5543easily, the main focus has always been on Linux during the design of 5544U-Boot. 5545 5546U-Boot includes many features that so far have been part of some 5547special "boot loader" code within the Linux kernel. Also, any 5548"initrd" images to be used are no longer part of one big Linux image; 5549instead, kernel and "initrd" are separate images. This implementation 5550serves several purposes: 5551 5552- the same features can be used for other OS or standalone 5553 applications (for instance: using compressed images to reduce the 5554 Flash memory footprint) 5555 5556- it becomes much easier to port new Linux kernel versions because 5557 lots of low-level, hardware dependent stuff are done by U-Boot 5558 5559- the same Linux kernel image can now be used with different "initrd" 5560 images; of course this also means that different kernel images can 5561 be run with the same "initrd". This makes testing easier (you don't 5562 have to build a new "zImage.initrd" Linux image when you just 5563 change a file in your "initrd"). Also, a field-upgrade of the 5564 software is easier now. 5565 5566 5567Linux HOWTO: 5568============ 5569 5570Porting Linux to U-Boot based systems: 5571--------------------------------------- 5572 5573U-Boot cannot save you from doing all the necessary modifications to 5574configure the Linux device drivers for use with your target hardware 5575(no, we don't intend to provide a full virtual machine interface to 5576Linux :-). 5577 5578But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5579 5580Just make sure your machine specific header file (for instance 5581include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5582Information structure as we define in include/asm-<arch>/u-boot.h, 5583and make sure that your definition of IMAP_ADDR uses the same value 5584as your U-Boot configuration in CONFIG_SYS_IMMR. 5585 5586Note that U-Boot now has a driver model, a unified model for drivers. 5587If you are adding a new driver, plumb it into driver model. If there 5588is no uclass available, you are encouraged to create one. See 5589doc/driver-model. 5590 5591 5592Configuring the Linux kernel: 5593----------------------------- 5594 5595No specific requirements for U-Boot. Make sure you have some root 5596device (initial ramdisk, NFS) for your target system. 5597 5598 5599Building a Linux Image: 5600----------------------- 5601 5602With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5603not used. If you use recent kernel source, a new build target 5604"uImage" will exist which automatically builds an image usable by 5605U-Boot. Most older kernels also have support for a "pImage" target, 5606which was introduced for our predecessor project PPCBoot and uses a 5607100% compatible format. 5608 5609Example: 5610 5611 make TQM850L_defconfig 5612 make oldconfig 5613 make dep 5614 make uImage 5615 5616The "uImage" build target uses a special tool (in 'tools/mkimage') to 5617encapsulate a compressed Linux kernel image with header information, 5618CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5619 5620* build a standard "vmlinux" kernel image (in ELF binary format): 5621 5622* convert the kernel into a raw binary image: 5623 5624 ${CROSS_COMPILE}-objcopy -O binary \ 5625 -R .note -R .comment \ 5626 -S vmlinux linux.bin 5627 5628* compress the binary image: 5629 5630 gzip -9 linux.bin 5631 5632* package compressed binary image for U-Boot: 5633 5634 mkimage -A ppc -O linux -T kernel -C gzip \ 5635 -a 0 -e 0 -n "Linux Kernel Image" \ 5636 -d linux.bin.gz uImage 5637 5638 5639The "mkimage" tool can also be used to create ramdisk images for use 5640with U-Boot, either separated from the Linux kernel image, or 5641combined into one file. "mkimage" encapsulates the images with a 64 5642byte header containing information about target architecture, 5643operating system, image type, compression method, entry points, time 5644stamp, CRC32 checksums, etc. 5645 5646"mkimage" can be called in two ways: to verify existing images and 5647print the header information, or to build new images. 5648 5649In the first form (with "-l" option) mkimage lists the information 5650contained in the header of an existing U-Boot image; this includes 5651checksum verification: 5652 5653 tools/mkimage -l image 5654 -l ==> list image header information 5655 5656The second form (with "-d" option) is used to build a U-Boot image 5657from a "data file" which is used as image payload: 5658 5659 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5660 -n name -d data_file image 5661 -A ==> set architecture to 'arch' 5662 -O ==> set operating system to 'os' 5663 -T ==> set image type to 'type' 5664 -C ==> set compression type 'comp' 5665 -a ==> set load address to 'addr' (hex) 5666 -e ==> set entry point to 'ep' (hex) 5667 -n ==> set image name to 'name' 5668 -d ==> use image data from 'datafile' 5669 5670Right now, all Linux kernels for PowerPC systems use the same load 5671address (0x00000000), but the entry point address depends on the 5672kernel version: 5673 5674- 2.2.x kernels have the entry point at 0x0000000C, 5675- 2.3.x and later kernels have the entry point at 0x00000000. 5676 5677So a typical call to build a U-Boot image would read: 5678 5679 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5680 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5681 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5682 > examples/uImage.TQM850L 5683 Image Name: 2.4.4 kernel for TQM850L 5684 Created: Wed Jul 19 02:34:59 2000 5685 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5686 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5687 Load Address: 0x00000000 5688 Entry Point: 0x00000000 5689 5690To verify the contents of the image (or check for corruption): 5691 5692 -> tools/mkimage -l examples/uImage.TQM850L 5693 Image Name: 2.4.4 kernel for TQM850L 5694 Created: Wed Jul 19 02:34:59 2000 5695 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5696 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5697 Load Address: 0x00000000 5698 Entry Point: 0x00000000 5699 5700NOTE: for embedded systems where boot time is critical you can trade 5701speed for memory and install an UNCOMPRESSED image instead: this 5702needs more space in Flash, but boots much faster since it does not 5703need to be uncompressed: 5704 5705 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5706 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5707 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5708 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5709 > examples/uImage.TQM850L-uncompressed 5710 Image Name: 2.4.4 kernel for TQM850L 5711 Created: Wed Jul 19 02:34:59 2000 5712 Image Type: PowerPC Linux Kernel Image (uncompressed) 5713 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5714 Load Address: 0x00000000 5715 Entry Point: 0x00000000 5716 5717 5718Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5719when your kernel is intended to use an initial ramdisk: 5720 5721 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5722 > -A ppc -O linux -T ramdisk -C gzip \ 5723 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5724 Image Name: Simple Ramdisk Image 5725 Created: Wed Jan 12 14:01:50 2000 5726 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5727 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5728 Load Address: 0x00000000 5729 Entry Point: 0x00000000 5730 5731The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5732option performs the converse operation of the mkimage's second form (the "-d" 5733option). Given an image built by mkimage, the dumpimage extracts a "data file" 5734from the image: 5735 5736 tools/dumpimage -i image -p position data_file 5737 -i ==> extract from the 'image' a specific 'data_file', \ 5738 indexed by 'position' 5739 5740 5741Installing a Linux Image: 5742------------------------- 5743 5744To downloading a U-Boot image over the serial (console) interface, 5745you must convert the image to S-Record format: 5746 5747 objcopy -I binary -O srec examples/image examples/image.srec 5748 5749The 'objcopy' does not understand the information in the U-Boot 5750image header, so the resulting S-Record file will be relative to 5751address 0x00000000. To load it to a given address, you need to 5752specify the target address as 'offset' parameter with the 'loads' 5753command. 5754 5755Example: install the image to address 0x40100000 (which on the 5756TQM8xxL is in the first Flash bank): 5757 5758 => erase 40100000 401FFFFF 5759 5760 .......... done 5761 Erased 8 sectors 5762 5763 => loads 40100000 5764 ## Ready for S-Record download ... 5765 ~>examples/image.srec 5766 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5767 ... 5768 15989 15990 15991 15992 5769 [file transfer complete] 5770 [connected] 5771 ## Start Addr = 0x00000000 5772 5773 5774You can check the success of the download using the 'iminfo' command; 5775this includes a checksum verification so you can be sure no data 5776corruption happened: 5777 5778 => imi 40100000 5779 5780 ## Checking Image at 40100000 ... 5781 Image Name: 2.2.13 for initrd on TQM850L 5782 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5783 Data Size: 335725 Bytes = 327 kB = 0 MB 5784 Load Address: 00000000 5785 Entry Point: 0000000c 5786 Verifying Checksum ... OK 5787 5788 5789Boot Linux: 5790----------- 5791 5792The "bootm" command is used to boot an application that is stored in 5793memory (RAM or Flash). In case of a Linux kernel image, the contents 5794of the "bootargs" environment variable is passed to the kernel as 5795parameters. You can check and modify this variable using the 5796"printenv" and "setenv" commands: 5797 5798 5799 => printenv bootargs 5800 bootargs=root=/dev/ram 5801 5802 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5803 5804 => printenv bootargs 5805 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5806 5807 => bootm 40020000 5808 ## Booting Linux kernel at 40020000 ... 5809 Image Name: 2.2.13 for NFS on TQM850L 5810 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5811 Data Size: 381681 Bytes = 372 kB = 0 MB 5812 Load Address: 00000000 5813 Entry Point: 0000000c 5814 Verifying Checksum ... OK 5815 Uncompressing Kernel Image ... OK 5816 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 5817 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5818 time_init: decrementer frequency = 187500000/60 5819 Calibrating delay loop... 49.77 BogoMIPS 5820 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5821 ... 5822 5823If you want to boot a Linux kernel with initial RAM disk, you pass 5824the memory addresses of both the kernel and the initrd image (PPBCOOT 5825format!) to the "bootm" command: 5826 5827 => imi 40100000 40200000 5828 5829 ## Checking Image at 40100000 ... 5830 Image Name: 2.2.13 for initrd on TQM850L 5831 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5832 Data Size: 335725 Bytes = 327 kB = 0 MB 5833 Load Address: 00000000 5834 Entry Point: 0000000c 5835 Verifying Checksum ... OK 5836 5837 ## Checking Image at 40200000 ... 5838 Image Name: Simple Ramdisk Image 5839 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5840 Data Size: 566530 Bytes = 553 kB = 0 MB 5841 Load Address: 00000000 5842 Entry Point: 00000000 5843 Verifying Checksum ... OK 5844 5845 => bootm 40100000 40200000 5846 ## Booting Linux kernel at 40100000 ... 5847 Image Name: 2.2.13 for initrd on TQM850L 5848 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5849 Data Size: 335725 Bytes = 327 kB = 0 MB 5850 Load Address: 00000000 5851 Entry Point: 0000000c 5852 Verifying Checksum ... OK 5853 Uncompressing Kernel Image ... OK 5854 ## Loading RAMDisk Image at 40200000 ... 5855 Image Name: Simple Ramdisk Image 5856 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5857 Data Size: 566530 Bytes = 553 kB = 0 MB 5858 Load Address: 00000000 5859 Entry Point: 00000000 5860 Verifying Checksum ... OK 5861 Loading Ramdisk ... OK 5862 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 5863 Boot arguments: root=/dev/ram 5864 time_init: decrementer frequency = 187500000/60 5865 Calibrating delay loop... 49.77 BogoMIPS 5866 ... 5867 RAMDISK: Compressed image found at block 0 5868 VFS: Mounted root (ext2 filesystem). 5869 5870 bash# 5871 5872Boot Linux and pass a flat device tree: 5873----------- 5874 5875First, U-Boot must be compiled with the appropriate defines. See the section 5876titled "Linux Kernel Interface" above for a more in depth explanation. The 5877following is an example of how to start a kernel and pass an updated 5878flat device tree: 5879 5880=> print oftaddr 5881oftaddr=0x300000 5882=> print oft 5883oft=oftrees/mpc8540ads.dtb 5884=> tftp $oftaddr $oft 5885Speed: 1000, full duplex 5886Using TSEC0 device 5887TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5888Filename 'oftrees/mpc8540ads.dtb'. 5889Load address: 0x300000 5890Loading: # 5891done 5892Bytes transferred = 4106 (100a hex) 5893=> tftp $loadaddr $bootfile 5894Speed: 1000, full duplex 5895Using TSEC0 device 5896TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5897Filename 'uImage'. 5898Load address: 0x200000 5899Loading:############ 5900done 5901Bytes transferred = 1029407 (fb51f hex) 5902=> print loadaddr 5903loadaddr=200000 5904=> print oftaddr 5905oftaddr=0x300000 5906=> bootm $loadaddr - $oftaddr 5907## Booting image at 00200000 ... 5908 Image Name: Linux-2.6.17-dirty 5909 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5910 Data Size: 1029343 Bytes = 1005.2 kB 5911 Load Address: 00000000 5912 Entry Point: 00000000 5913 Verifying Checksum ... OK 5914 Uncompressing Kernel Image ... OK 5915Booting using flat device tree at 0x300000 5916Using MPC85xx ADS machine description 5917Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5918[snip] 5919 5920 5921More About U-Boot Image Types: 5922------------------------------ 5923 5924U-Boot supports the following image types: 5925 5926 "Standalone Programs" are directly runnable in the environment 5927 provided by U-Boot; it is expected that (if they behave 5928 well) you can continue to work in U-Boot after return from 5929 the Standalone Program. 5930 "OS Kernel Images" are usually images of some Embedded OS which 5931 will take over control completely. Usually these programs 5932 will install their own set of exception handlers, device 5933 drivers, set up the MMU, etc. - this means, that you cannot 5934 expect to re-enter U-Boot except by resetting the CPU. 5935 "RAMDisk Images" are more or less just data blocks, and their 5936 parameters (address, size) are passed to an OS kernel that is 5937 being started. 5938 "Multi-File Images" contain several images, typically an OS 5939 (Linux) kernel image and one or more data images like 5940 RAMDisks. This construct is useful for instance when you want 5941 to boot over the network using BOOTP etc., where the boot 5942 server provides just a single image file, but you want to get 5943 for instance an OS kernel and a RAMDisk image. 5944 5945 "Multi-File Images" start with a list of image sizes, each 5946 image size (in bytes) specified by an "uint32_t" in network 5947 byte order. This list is terminated by an "(uint32_t)0". 5948 Immediately after the terminating 0 follow the images, one by 5949 one, all aligned on "uint32_t" boundaries (size rounded up to 5950 a multiple of 4 bytes). 5951 5952 "Firmware Images" are binary images containing firmware (like 5953 U-Boot or FPGA images) which usually will be programmed to 5954 flash memory. 5955 5956 "Script files" are command sequences that will be executed by 5957 U-Boot's command interpreter; this feature is especially 5958 useful when you configure U-Boot to use a real shell (hush) 5959 as command interpreter. 5960 5961Booting the Linux zImage: 5962------------------------- 5963 5964On some platforms, it's possible to boot Linux zImage. This is done 5965using the "bootz" command. The syntax of "bootz" command is the same 5966as the syntax of "bootm" command. 5967 5968Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5969kernel with raw initrd images. The syntax is slightly different, the 5970address of the initrd must be augmented by it's size, in the following 5971format: "<initrd addres>:<initrd size>". 5972 5973 5974Standalone HOWTO: 5975================= 5976 5977One of the features of U-Boot is that you can dynamically load and 5978run "standalone" applications, which can use some resources of 5979U-Boot like console I/O functions or interrupt services. 5980 5981Two simple examples are included with the sources: 5982 5983"Hello World" Demo: 5984------------------- 5985 5986'examples/hello_world.c' contains a small "Hello World" Demo 5987application; it is automatically compiled when you build U-Boot. 5988It's configured to run at address 0x00040004, so you can play with it 5989like that: 5990 5991 => loads 5992 ## Ready for S-Record download ... 5993 ~>examples/hello_world.srec 5994 1 2 3 4 5 6 7 8 9 10 11 ... 5995 [file transfer complete] 5996 [connected] 5997 ## Start Addr = 0x00040004 5998 5999 => go 40004 Hello World! This is a test. 6000 ## Starting application at 0x00040004 ... 6001 Hello World 6002 argc = 7 6003 argv[0] = "40004" 6004 argv[1] = "Hello" 6005 argv[2] = "World!" 6006 argv[3] = "This" 6007 argv[4] = "is" 6008 argv[5] = "a" 6009 argv[6] = "test." 6010 argv[7] = "<NULL>" 6011 Hit any key to exit ... 6012 6013 ## Application terminated, rc = 0x0 6014 6015Another example, which demonstrates how to register a CPM interrupt 6016handler with the U-Boot code, can be found in 'examples/timer.c'. 6017Here, a CPM timer is set up to generate an interrupt every second. 6018The interrupt service routine is trivial, just printing a '.' 6019character, but this is just a demo program. The application can be 6020controlled by the following keys: 6021 6022 ? - print current values og the CPM Timer registers 6023 b - enable interrupts and start timer 6024 e - stop timer and disable interrupts 6025 q - quit application 6026 6027 => loads 6028 ## Ready for S-Record download ... 6029 ~>examples/timer.srec 6030 1 2 3 4 5 6 7 8 9 10 11 ... 6031 [file transfer complete] 6032 [connected] 6033 ## Start Addr = 0x00040004 6034 6035 => go 40004 6036 ## Starting application at 0x00040004 ... 6037 TIMERS=0xfff00980 6038 Using timer 1 6039 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 6040 6041Hit 'b': 6042 [q, b, e, ?] Set interval 1000000 us 6043 Enabling timer 6044Hit '?': 6045 [q, b, e, ?] ........ 6046 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 6047Hit '?': 6048 [q, b, e, ?] . 6049 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 6050Hit '?': 6051 [q, b, e, ?] . 6052 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 6053Hit '?': 6054 [q, b, e, ?] . 6055 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 6056Hit 'e': 6057 [q, b, e, ?] ...Stopping timer 6058Hit 'q': 6059 [q, b, e, ?] ## Application terminated, rc = 0x0 6060 6061 6062Minicom warning: 6063================ 6064 6065Over time, many people have reported problems when trying to use the 6066"minicom" terminal emulation program for serial download. I (wd) 6067consider minicom to be broken, and recommend not to use it. Under 6068Unix, I recommend to use C-Kermit for general purpose use (and 6069especially for kermit binary protocol download ("loadb" command), and 6070use "cu" for S-Record download ("loads" command). See 6071http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 6072for help with kermit. 6073 6074 6075Nevertheless, if you absolutely want to use it try adding this 6076configuration to your "File transfer protocols" section: 6077 6078 Name Program Name U/D FullScr IO-Red. Multi 6079 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 6080 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 6081 6082 6083NetBSD Notes: 6084============= 6085 6086Starting at version 0.9.2, U-Boot supports NetBSD both as host 6087(build U-Boot) and target system (boots NetBSD/mpc8xx). 6088 6089Building requires a cross environment; it is known to work on 6090NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 6091need gmake since the Makefiles are not compatible with BSD make). 6092Note that the cross-powerpc package does not install include files; 6093attempting to build U-Boot will fail because <machine/ansi.h> is 6094missing. This file has to be installed and patched manually: 6095 6096 # cd /usr/pkg/cross/powerpc-netbsd/include 6097 # mkdir powerpc 6098 # ln -s powerpc machine 6099 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 6100 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 6101 6102Native builds *don't* work due to incompatibilities between native 6103and U-Boot include files. 6104 6105Booting assumes that (the first part of) the image booted is a 6106stage-2 loader which in turn loads and then invokes the kernel 6107proper. Loader sources will eventually appear in the NetBSD source 6108tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 6109meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 6110 6111 6112Implementation Internals: 6113========================= 6114 6115The following is not intended to be a complete description of every 6116implementation detail. However, it should help to understand the 6117inner workings of U-Boot and make it easier to port it to custom 6118hardware. 6119 6120 6121Initial Stack, Global Data: 6122--------------------------- 6123 6124The implementation of U-Boot is complicated by the fact that U-Boot 6125starts running out of ROM (flash memory), usually without access to 6126system RAM (because the memory controller is not initialized yet). 6127This means that we don't have writable Data or BSS segments, and BSS 6128is not initialized as zero. To be able to get a C environment working 6129at all, we have to allocate at least a minimal stack. Implementation 6130options for this are defined and restricted by the CPU used: Some CPU 6131models provide on-chip memory (like the IMMR area on MPC8xx and 6132MPC826x processors), on others (parts of) the data cache can be 6133locked as (mis-) used as memory, etc. 6134 6135 Chris Hallinan posted a good summary of these issues to the 6136 U-Boot mailing list: 6137 6138 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 6139 From: "Chris Hallinan" <clh@net1plus.com> 6140 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 6141 ... 6142 6143 Correct me if I'm wrong, folks, but the way I understand it 6144 is this: Using DCACHE as initial RAM for Stack, etc, does not 6145 require any physical RAM backing up the cache. The cleverness 6146 is that the cache is being used as a temporary supply of 6147 necessary storage before the SDRAM controller is setup. It's 6148 beyond the scope of this list to explain the details, but you 6149 can see how this works by studying the cache architecture and 6150 operation in the architecture and processor-specific manuals. 6151 6152 OCM is On Chip Memory, which I believe the 405GP has 4K. It 6153 is another option for the system designer to use as an 6154 initial stack/RAM area prior to SDRAM being available. Either 6155 option should work for you. Using CS 4 should be fine if your 6156 board designers haven't used it for something that would 6157 cause you grief during the initial boot! It is frequently not 6158 used. 6159 6160 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 6161 with your processor/board/system design. The default value 6162 you will find in any recent u-boot distribution in 6163 walnut.h should work for you. I'd set it to a value larger 6164 than your SDRAM module. If you have a 64MB SDRAM module, set 6165 it above 400_0000. Just make sure your board has no resources 6166 that are supposed to respond to that address! That code in 6167 start.S has been around a while and should work as is when 6168 you get the config right. 6169 6170 -Chris Hallinan 6171 DS4.COM, Inc. 6172 6173It is essential to remember this, since it has some impact on the C 6174code for the initialization procedures: 6175 6176* Initialized global data (data segment) is read-only. Do not attempt 6177 to write it. 6178 6179* Do not use any uninitialized global data (or implicitely initialized 6180 as zero data - BSS segment) at all - this is undefined, initiali- 6181 zation is performed later (when relocating to RAM). 6182 6183* Stack space is very limited. Avoid big data buffers or things like 6184 that. 6185 6186Having only the stack as writable memory limits means we cannot use 6187normal global data to share information beween the code. But it 6188turned out that the implementation of U-Boot can be greatly 6189simplified by making a global data structure (gd_t) available to all 6190functions. We could pass a pointer to this data as argument to _all_ 6191functions, but this would bloat the code. Instead we use a feature of 6192the GCC compiler (Global Register Variables) to share the data: we 6193place a pointer (gd) to the global data into a register which we 6194reserve for this purpose. 6195 6196When choosing a register for such a purpose we are restricted by the 6197relevant (E)ABI specifications for the current architecture, and by 6198GCC's implementation. 6199 6200For PowerPC, the following registers have specific use: 6201 R1: stack pointer 6202 R2: reserved for system use 6203 R3-R4: parameter passing and return values 6204 R5-R10: parameter passing 6205 R13: small data area pointer 6206 R30: GOT pointer 6207 R31: frame pointer 6208 6209 (U-Boot also uses R12 as internal GOT pointer. r12 6210 is a volatile register so r12 needs to be reset when 6211 going back and forth between asm and C) 6212 6213 ==> U-Boot will use R2 to hold a pointer to the global data 6214 6215 Note: on PPC, we could use a static initializer (since the 6216 address of the global data structure is known at compile time), 6217 but it turned out that reserving a register results in somewhat 6218 smaller code - although the code savings are not that big (on 6219 average for all boards 752 bytes for the whole U-Boot image, 6220 624 text + 127 data). 6221 6222On Blackfin, the normal C ABI (except for P3) is followed as documented here: 6223 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 6224 6225 ==> U-Boot will use P3 to hold a pointer to the global data 6226 6227On ARM, the following registers are used: 6228 6229 R0: function argument word/integer result 6230 R1-R3: function argument word 6231 R9: platform specific 6232 R10: stack limit (used only if stack checking is enabled) 6233 R11: argument (frame) pointer 6234 R12: temporary workspace 6235 R13: stack pointer 6236 R14: link register 6237 R15: program counter 6238 6239 ==> U-Boot will use R9 to hold a pointer to the global data 6240 6241 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 6242 6243On Nios II, the ABI is documented here: 6244 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 6245 6246 ==> U-Boot will use gp to hold a pointer to the global data 6247 6248 Note: on Nios II, we give "-G0" option to gcc and don't use gp 6249 to access small data sections, so gp is free. 6250 6251On NDS32, the following registers are used: 6252 6253 R0-R1: argument/return 6254 R2-R5: argument 6255 R15: temporary register for assembler 6256 R16: trampoline register 6257 R28: frame pointer (FP) 6258 R29: global pointer (GP) 6259 R30: link register (LP) 6260 R31: stack pointer (SP) 6261 PC: program counter (PC) 6262 6263 ==> U-Boot will use R10 to hold a pointer to the global data 6264 6265NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 6266or current versions of GCC may "optimize" the code too much. 6267 6268Memory Management: 6269------------------ 6270 6271U-Boot runs in system state and uses physical addresses, i.e. the 6272MMU is not used either for address mapping nor for memory protection. 6273 6274The available memory is mapped to fixed addresses using the memory 6275controller. In this process, a contiguous block is formed for each 6276memory type (Flash, SDRAM, SRAM), even when it consists of several 6277physical memory banks. 6278 6279U-Boot is installed in the first 128 kB of the first Flash bank (on 6280TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 6281booting and sizing and initializing DRAM, the code relocates itself 6282to the upper end of DRAM. Immediately below the U-Boot code some 6283memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 6284configuration setting]. Below that, a structure with global Board 6285Info data is placed, followed by the stack (growing downward). 6286 6287Additionally, some exception handler code is copied to the low 8 kB 6288of DRAM (0x00000000 ... 0x00001FFF). 6289 6290So a typical memory configuration with 16 MB of DRAM could look like 6291this: 6292 6293 0x0000 0000 Exception Vector code 6294 : 6295 0x0000 1FFF 6296 0x0000 2000 Free for Application Use 6297 : 6298 : 6299 6300 : 6301 : 6302 0x00FB FF20 Monitor Stack (Growing downward) 6303 0x00FB FFAC Board Info Data and permanent copy of global data 6304 0x00FC 0000 Malloc Arena 6305 : 6306 0x00FD FFFF 6307 0x00FE 0000 RAM Copy of Monitor Code 6308 ... eventually: LCD or video framebuffer 6309 ... eventually: pRAM (Protected RAM - unchanged by reset) 6310 0x00FF FFFF [End of RAM] 6311 6312 6313System Initialization: 6314---------------------- 6315 6316In the reset configuration, U-Boot starts at the reset entry point 6317(on most PowerPC systems at address 0x00000100). Because of the reset 6318configuration for CS0# this is a mirror of the onboard Flash memory. 6319To be able to re-map memory U-Boot then jumps to its link address. 6320To be able to implement the initialization code in C, a (small!) 6321initial stack is set up in the internal Dual Ported RAM (in case CPUs 6322which provide such a feature like MPC8xx or MPC8260), or in a locked 6323part of the data cache. After that, U-Boot initializes the CPU core, 6324the caches and the SIU. 6325 6326Next, all (potentially) available memory banks are mapped using a 6327preliminary mapping. For example, we put them on 512 MB boundaries 6328(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6329on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6330programmed for SDRAM access. Using the temporary configuration, a 6331simple memory test is run that determines the size of the SDRAM 6332banks. 6333 6334When there is more than one SDRAM bank, and the banks are of 6335different size, the largest is mapped first. For equal size, the first 6336bank (CS2#) is mapped first. The first mapping is always for address 63370x00000000, with any additional banks following immediately to create 6338contiguous memory starting from 0. 6339 6340Then, the monitor installs itself at the upper end of the SDRAM area 6341and allocates memory for use by malloc() and for the global Board 6342Info data; also, the exception vector code is copied to the low RAM 6343pages, and the final stack is set up. 6344 6345Only after this relocation will you have a "normal" C environment; 6346until that you are restricted in several ways, mostly because you are 6347running from ROM, and because the code will have to be relocated to a 6348new address in RAM. 6349 6350 6351U-Boot Porting Guide: 6352---------------------- 6353 6354[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6355list, October 2002] 6356 6357 6358int main(int argc, char *argv[]) 6359{ 6360 sighandler_t no_more_time; 6361 6362 signal(SIGALRM, no_more_time); 6363 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6364 6365 if (available_money > available_manpower) { 6366 Pay consultant to port U-Boot; 6367 return 0; 6368 } 6369 6370 Download latest U-Boot source; 6371 6372 Subscribe to u-boot mailing list; 6373 6374 if (clueless) 6375 email("Hi, I am new to U-Boot, how do I get started?"); 6376 6377 while (learning) { 6378 Read the README file in the top level directory; 6379 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6380 Read applicable doc/*.README; 6381 Read the source, Luke; 6382 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6383 } 6384 6385 if (available_money > toLocalCurrency ($2500)) 6386 Buy a BDI3000; 6387 else 6388 Add a lot of aggravation and time; 6389 6390 if (a similar board exists) { /* hopefully... */ 6391 cp -a board/<similar> board/<myboard> 6392 cp include/configs/<similar>.h include/configs/<myboard>.h 6393 } else { 6394 Create your own board support subdirectory; 6395 Create your own board include/configs/<myboard>.h file; 6396 } 6397 Edit new board/<myboard> files 6398 Edit new include/configs/<myboard>.h 6399 6400 while (!accepted) { 6401 while (!running) { 6402 do { 6403 Add / modify source code; 6404 } until (compiles); 6405 Debug; 6406 if (clueless) 6407 email("Hi, I am having problems..."); 6408 } 6409 Send patch file to the U-Boot email list; 6410 if (reasonable critiques) 6411 Incorporate improvements from email list code review; 6412 else 6413 Defend code as written; 6414 } 6415 6416 return 0; 6417} 6418 6419void no_more_time (int sig) 6420{ 6421 hire_a_guru(); 6422} 6423 6424 6425Coding Standards: 6426----------------- 6427 6428All contributions to U-Boot should conform to the Linux kernel 6429coding style; see the file "Documentation/CodingStyle" and the script 6430"scripts/Lindent" in your Linux kernel source directory. 6431 6432Source files originating from a different project (for example the 6433MTD subsystem) are generally exempt from these guidelines and are not 6434reformated to ease subsequent migration to newer versions of those 6435sources. 6436 6437Please note that U-Boot is implemented in C (and to some small parts in 6438Assembler); no C++ is used, so please do not use C++ style comments (//) 6439in your code. 6440 6441Please also stick to the following formatting rules: 6442- remove any trailing white space 6443- use TAB characters for indentation and vertical alignment, not spaces 6444- make sure NOT to use DOS '\r\n' line feeds 6445- do not add more than 2 consecutive empty lines to source files 6446- do not add trailing empty lines to source files 6447 6448Submissions which do not conform to the standards may be returned 6449with a request to reformat the changes. 6450 6451 6452Submitting Patches: 6453------------------- 6454 6455Since the number of patches for U-Boot is growing, we need to 6456establish some rules. Submissions which do not conform to these rules 6457may be rejected, even when they contain important and valuable stuff. 6458 6459Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6460 6461Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6462see http://lists.denx.de/mailman/listinfo/u-boot 6463 6464When you send a patch, please include the following information with 6465it: 6466 6467* For bug fixes: a description of the bug and how your patch fixes 6468 this bug. Please try to include a way of demonstrating that the 6469 patch actually fixes something. 6470 6471* For new features: a description of the feature and your 6472 implementation. 6473 6474* A CHANGELOG entry as plaintext (separate from the patch) 6475 6476* For major contributions, your entry to the CREDITS file 6477 6478* When you add support for a new board, don't forget to add a 6479 maintainer e-mail address to the boards.cfg file, too. 6480 6481* If your patch adds new configuration options, don't forget to 6482 document these in the README file. 6483 6484* The patch itself. If you are using git (which is *strongly* 6485 recommended) you can easily generate the patch using the 6486 "git format-patch". If you then use "git send-email" to send it to 6487 the U-Boot mailing list, you will avoid most of the common problems 6488 with some other mail clients. 6489 6490 If you cannot use git, use "diff -purN OLD NEW". If your version of 6491 diff does not support these options, then get the latest version of 6492 GNU diff. 6493 6494 The current directory when running this command shall be the parent 6495 directory of the U-Boot source tree (i. e. please make sure that 6496 your patch includes sufficient directory information for the 6497 affected files). 6498 6499 We prefer patches as plain text. MIME attachments are discouraged, 6500 and compressed attachments must not be used. 6501 6502* If one logical set of modifications affects or creates several 6503 files, all these changes shall be submitted in a SINGLE patch file. 6504 6505* Changesets that contain different, unrelated modifications shall be 6506 submitted as SEPARATE patches, one patch per changeset. 6507 6508 6509Notes: 6510 6511* Before sending the patch, run the MAKEALL script on your patched 6512 source tree and make sure that no errors or warnings are reported 6513 for any of the boards. 6514 6515* Keep your modifications to the necessary minimum: A patch 6516 containing several unrelated changes or arbitrary reformats will be 6517 returned with a request to re-formatting / split it. 6518 6519* If you modify existing code, make sure that your new code does not 6520 add to the memory footprint of the code ;-) Small is beautiful! 6521 When adding new features, these should compile conditionally only 6522 (using #ifdef), and the resulting code with the new feature 6523 disabled must not need more memory than the old code without your 6524 modification. 6525 6526* Remember that there is a size limit of 100 kB per message on the 6527 u-boot mailing list. Bigger patches will be moderated. If they are 6528 reasonable and not too big, they will be acknowledged. But patches 6529 bigger than the size limit should be avoided. 6530