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 file to find out who contributed 38the specific port. In addition, there are various MAINTAINERS files 39scattered throughout the U-Boot source identifying the people or 40companies responsible for various boards and subsystems. 41 42Note: As of August, 2010, there is no longer a CHANGELOG file in the 43actual U-Boot source tree; however, it can be created dynamically 44from the Git log using: 45 46 make CHANGELOG 47 48 49Where to get help: 50================== 51 52In case you have questions about, problems with or contributions for 53U-Boot, you should send a message to the U-Boot mailing list at 54<u-boot@lists.denx.de>. There is also an archive of previous traffic 55on the mailing list - please search the archive before asking FAQ's. 56Please see http://lists.denx.de/pipermail/u-boot and 57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 58 59 60Where to get source code: 61========================= 62 63The U-Boot source code is maintained in the Git repository at 64git://www.denx.de/git/u-boot.git ; you can browse it online at 65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 66 67The "snapshot" links on this page allow you to download tarballs of 68any version you might be interested in. Official releases are also 69available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 70directory. 71 72Pre-built (and tested) images are available from 73ftp://ftp.denx.de/pub/u-boot/images/ 74 75 76Where we come from: 77=================== 78 79- start from 8xxrom sources 80- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 81- clean up code 82- make it easier to add custom boards 83- make it possible to add other [PowerPC] CPUs 84- extend functions, especially: 85 * Provide extended interface to Linux boot loader 86 * S-Record download 87 * network boot 88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 89- create ARMBoot project (http://sourceforge.net/projects/armboot) 90- add other CPU families (starting with ARM) 91- create U-Boot project (http://sourceforge.net/projects/u-boot) 92- current project page: see http://www.denx.de/wiki/U-Boot 93 94 95Names and Spelling: 96=================== 97 98The "official" name of this project is "Das U-Boot". The spelling 99"U-Boot" shall be used in all written text (documentation, comments 100in source files etc.). Example: 101 102 This is the README file for the U-Boot project. 103 104File names etc. shall be based on the string "u-boot". Examples: 105 106 include/asm-ppc/u-boot.h 107 108 #include <asm/u-boot.h> 109 110Variable names, preprocessor constants etc. shall be either based on 111the string "u_boot" or on "U_BOOT". Example: 112 113 U_BOOT_VERSION u_boot_logo 114 IH_OS_U_BOOT u_boot_hush_start 115 116 117Versioning: 118=========== 119 120Starting with the release in October 2008, the names of the releases 121were changed from numerical release numbers without deeper meaning 122into a time stamp based numbering. Regular releases are identified by 123names consisting of the calendar year and month of the release date. 124Additional fields (if present) indicate release candidates or bug fix 125releases in "stable" maintenance trees. 126 127Examples: 128 U-Boot v2009.11 - Release November 2009 129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 130 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release 131 132 133Directory Hierarchy: 134==================== 135 136/arch Architecture specific files 137 /arc Files generic to ARC architecture 138 /arm Files generic to ARM architecture 139 /avr32 Files generic to AVR32 architecture 140 /m68k Files generic to m68k architecture 141 /microblaze Files generic to microblaze architecture 142 /mips Files generic to MIPS architecture 143 /nds32 Files generic to NDS32 architecture 144 /nios2 Files generic to Altera NIOS2 architecture 145 /openrisc Files generic to OpenRISC architecture 146 /powerpc Files generic to PowerPC architecture 147 /sandbox Files generic to HW-independent "sandbox" 148 /sh Files generic to SH architecture 149 /x86 Files generic to x86 architecture 150/api Machine/arch independent API for external apps 151/board Board dependent files 152/cmd U-Boot commands functions 153/common Misc architecture independent functions 154/configs Board default configuration files 155/disk Code for disk drive partition handling 156/doc Documentation (don't expect too much) 157/drivers Commonly used device drivers 158/dts Contains Makefile for building internal U-Boot fdt. 159/examples Example code for standalone applications, etc. 160/fs Filesystem code (cramfs, ext2, jffs2, etc.) 161/include Header Files 162/lib Library routines generic to all architectures 163/Licenses Various license files 164/net Networking code 165/post Power On Self Test 166/scripts Various build scripts and Makefiles 167/test Various unit test files 168/tools Tools to build S-Record or U-Boot images, etc. 169 170Software Configuration: 171======================= 172 173Configuration is usually done using C preprocessor defines; the 174rationale behind that is to avoid dead code whenever possible. 175 176There are two classes of configuration variables: 177 178* Configuration _OPTIONS_: 179 These are selectable by the user and have names beginning with 180 "CONFIG_". 181 182* Configuration _SETTINGS_: 183 These depend on the hardware etc. and should not be meddled with if 184 you don't know what you're doing; they have names beginning with 185 "CONFIG_SYS_". 186 187Previously, all configuration was done by hand, which involved creating 188symbolic links and editing configuration files manually. More recently, 189U-Boot has added the Kbuild infrastructure used by the Linux kernel, 190allowing you to use the "make menuconfig" command to configure your 191build. 192 193 194Selection of Processor Architecture and Board Type: 195--------------------------------------------------- 196 197For all supported boards there are ready-to-use default 198configurations available; just type "make <board_name>_defconfig". 199 200Example: For a TQM823L module type: 201 202 cd u-boot 203 make TQM823L_defconfig 204 205Note: If you're looking for the default configuration file for a board 206you're sure used to be there but is now missing, check the file 207doc/README.scrapyard for a list of no longer supported boards. 208 209Sandbox Environment: 210-------------------- 211 212U-Boot can be built natively to run on a Linux host using the 'sandbox' 213board. This allows feature development which is not board- or architecture- 214specific to be undertaken on a native platform. The sandbox is also used to 215run some of U-Boot's tests. 216 217See board/sandbox/README.sandbox for more details. 218 219 220Board Initialisation Flow: 221-------------------------- 222 223This is the intended start-up flow for boards. This should apply for both 224SPL and U-Boot proper (i.e. they both follow the same rules). 225 226Note: "SPL" stands for "Secondary Program Loader," which is explained in 227more detail later in this file. 228 229At present, SPL mostly uses a separate code path, but the function names 230and roles of each function are the same. Some boards or architectures 231may not conform to this. At least most ARM boards which use 232CONFIG_SPL_FRAMEWORK conform to this. 233 234Execution typically starts with an architecture-specific (and possibly 235CPU-specific) start.S file, such as: 236 237 - arch/arm/cpu/armv7/start.S 238 - arch/powerpc/cpu/mpc83xx/start.S 239 - arch/mips/cpu/start.S 240 241and so on. From there, three functions are called; the purpose and 242limitations of each of these functions are described below. 243 244lowlevel_init(): 245 - purpose: essential init to permit execution to reach board_init_f() 246 - no global_data or BSS 247 - there is no stack (ARMv7 may have one but it will soon be removed) 248 - must not set up SDRAM or use console 249 - must only do the bare minimum to allow execution to continue to 250 board_init_f() 251 - this is almost never needed 252 - return normally from this function 253 254board_init_f(): 255 - purpose: set up the machine ready for running board_init_r(): 256 i.e. SDRAM and serial UART 257 - global_data is available 258 - stack is in SRAM 259 - BSS is not available, so you cannot use global/static variables, 260 only stack variables and global_data 261 262 Non-SPL-specific notes: 263 - dram_init() is called to set up DRAM. If already done in SPL this 264 can do nothing 265 266 SPL-specific notes: 267 - you can override the entire board_init_f() function with your own 268 version as needed. 269 - preloader_console_init() can be called here in extremis 270 - should set up SDRAM, and anything needed to make the UART work 271 - these is no need to clear BSS, it will be done by crt0.S 272 - must return normally from this function (don't call board_init_r() 273 directly) 274 275Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 276this point the stack and global_data are relocated to below 277CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 278memory. 279 280board_init_r(): 281 - purpose: main execution, common code 282 - global_data is available 283 - SDRAM is available 284 - BSS is available, all static/global variables can be used 285 - execution eventually continues to main_loop() 286 287 Non-SPL-specific notes: 288 - U-Boot is relocated to the top of memory and is now running from 289 there. 290 291 SPL-specific notes: 292 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 293 CONFIG_SPL_STACK_R_ADDR points into SDRAM 294 - preloader_console_init() can be called here - typically this is 295 done by defining CONFIG_SPL_BOARD_INIT and then supplying a 296 spl_board_init() function containing this call 297 - loads U-Boot or (in falcon mode) Linux 298 299 300 301Configuration Options: 302---------------------- 303 304Configuration depends on the combination of board and CPU type; all 305such information is kept in a configuration file 306"include/configs/<board_name>.h". 307 308Example: For a TQM823L module, all configuration settings are in 309"include/configs/TQM823L.h". 310 311 312Many of the options are named exactly as the corresponding Linux 313kernel configuration options. The intention is to make it easier to 314build a config tool - later. 315 316 317The following options need to be configured: 318 319- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 320 321- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 322 323- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 324 Define exactly one, e.g. CONFIG_ATSTK1002 325 326- Marvell Family Member 327 CONFIG_SYS_MVFS - define it if you want to enable 328 multiple fs option at one time 329 for marvell soc family 330 331- 8xx CPU Options: (if using an MPC8xx CPU) 332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 333 get_gclk_freq() cannot work 334 e.g. if there is no 32KHz 335 reference PIT/RTC clock 336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 337 or XTAL/EXTAL) 338 339- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 340 CONFIG_SYS_8xx_CPUCLK_MIN 341 CONFIG_SYS_8xx_CPUCLK_MAX 342 CONFIG_8xx_CPUCLK_DEFAULT 343 See doc/README.MPC866 344 345 CONFIG_SYS_MEASURE_CPUCLK 346 347 Define this to measure the actual CPU clock instead 348 of relying on the correctness of the configured 349 values. Mostly useful for board bringup to make sure 350 the PLL is locked at the intended frequency. Note 351 that this requires a (stable) reference clock (32 kHz 352 RTC clock or CONFIG_SYS_8XX_XIN) 353 354 CONFIG_SYS_DELAYED_ICACHE 355 356 Define this option if you want to enable the 357 ICache only when Code runs from RAM. 358 359- 85xx CPU Options: 360 CONFIG_SYS_PPC64 361 362 Specifies that the core is a 64-bit PowerPC implementation (implements 363 the "64" category of the Power ISA). This is necessary for ePAPR 364 compliance, among other possible reasons. 365 366 CONFIG_SYS_FSL_TBCLK_DIV 367 368 Defines the core time base clock divider ratio compared to the 369 system clock. On most PQ3 devices this is 8, on newer QorIQ 370 devices it can be 16 or 32. The ratio varies from SoC to Soc. 371 372 CONFIG_SYS_FSL_PCIE_COMPAT 373 374 Defines the string to utilize when trying to match PCIe device 375 tree nodes for the given platform. 376 377 CONFIG_SYS_FSL_ERRATUM_A004510 378 379 Enables a workaround for erratum A004510. If set, 380 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 381 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 382 383 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 384 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 385 386 Defines one or two SoC revisions (low 8 bits of SVR) 387 for which the A004510 workaround should be applied. 388 389 The rest of SVR is either not relevant to the decision 390 of whether the erratum is present (e.g. p2040 versus 391 p2041) or is implied by the build target, which controls 392 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 393 394 See Freescale App Note 4493 for more information about 395 this erratum. 396 397 CONFIG_A003399_NOR_WORKAROUND 398 Enables a workaround for IFC erratum A003399. It is only 399 required during NOR boot. 400 401 CONFIG_A008044_WORKAROUND 402 Enables a workaround for T1040/T1042 erratum A008044. It is only 403 required during NAND boot and valid for Rev 1.0 SoC revision 404 405 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 406 407 This is the value to write into CCSR offset 0x18600 408 according to the A004510 workaround. 409 410 CONFIG_SYS_FSL_DSP_DDR_ADDR 411 This value denotes start offset of DDR memory which is 412 connected exclusively to the DSP cores. 413 414 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 415 This value denotes start offset of M2 memory 416 which is directly connected to the DSP core. 417 418 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 419 This value denotes start offset of M3 memory which is directly 420 connected to the DSP core. 421 422 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 423 This value denotes start offset of DSP CCSR space. 424 425 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 426 Single Source Clock is clocking mode present in some of FSL SoC's. 427 In this mode, a single differential clock is used to supply 428 clocks to the sysclock, ddrclock and usbclock. 429 430 CONFIG_SYS_CPC_REINIT_F 431 This CONFIG is defined when the CPC is configured as SRAM at the 432 time of U-Boot entry and is required to be re-initialized. 433 434 CONFIG_DEEP_SLEEP 435 Indicates this SoC supports deep sleep feature. If deep sleep is 436 supported, core will start to execute uboot when wakes up. 437 438- Generic CPU options: 439 CONFIG_SYS_GENERIC_GLOBAL_DATA 440 Defines global data is initialized in generic board board_init_f(). 441 If this macro is defined, global data is created and cleared in 442 generic board board_init_f(). Without this macro, architecture/board 443 should initialize global data before calling board_init_f(). 444 445 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 446 447 Defines the endianess of the CPU. Implementation of those 448 values is arch specific. 449 450 CONFIG_SYS_FSL_DDR 451 Freescale DDR driver in use. This type of DDR controller is 452 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 453 SoCs. 454 455 CONFIG_SYS_FSL_DDR_ADDR 456 Freescale DDR memory-mapped register base. 457 458 CONFIG_SYS_FSL_DDR_EMU 459 Specify emulator support for DDR. Some DDR features such as 460 deskew training are not available. 461 462 CONFIG_SYS_FSL_DDRC_GEN1 463 Freescale DDR1 controller. 464 465 CONFIG_SYS_FSL_DDRC_GEN2 466 Freescale DDR2 controller. 467 468 CONFIG_SYS_FSL_DDRC_GEN3 469 Freescale DDR3 controller. 470 471 CONFIG_SYS_FSL_DDRC_GEN4 472 Freescale DDR4 controller. 473 474 CONFIG_SYS_FSL_DDRC_ARM_GEN3 475 Freescale DDR3 controller for ARM-based SoCs. 476 477 CONFIG_SYS_FSL_DDR1 478 Board config to use DDR1. It can be enabled for SoCs with 479 Freescale DDR1 or DDR2 controllers, depending on the board 480 implemetation. 481 482 CONFIG_SYS_FSL_DDR2 483 Board config to use DDR2. It can be enabled for SoCs with 484 Freescale DDR2 or DDR3 controllers, depending on the board 485 implementation. 486 487 CONFIG_SYS_FSL_DDR3 488 Board config to use DDR3. It can be enabled for SoCs with 489 Freescale DDR3 or DDR3L controllers. 490 491 CONFIG_SYS_FSL_DDR3L 492 Board config to use DDR3L. It can be enabled for SoCs with 493 DDR3L controllers. 494 495 CONFIG_SYS_FSL_DDR4 496 Board config to use DDR4. It can be enabled for SoCs with 497 DDR4 controllers. 498 499 CONFIG_SYS_FSL_IFC_BE 500 Defines the IFC controller register space as Big Endian 501 502 CONFIG_SYS_FSL_IFC_LE 503 Defines the IFC controller register space as Little Endian 504 505 CONFIG_SYS_FSL_IFC_CLK_DIV 506 Defines divider of platform clock(clock input to IFC controller). 507 508 CONFIG_SYS_FSL_LBC_CLK_DIV 509 Defines divider of platform clock(clock input to eLBC controller). 510 511 CONFIG_SYS_FSL_PBL_PBI 512 It enables addition of RCW (Power on reset configuration) in built image. 513 Please refer doc/README.pblimage for more details 514 515 CONFIG_SYS_FSL_PBL_RCW 516 It adds PBI(pre-boot instructions) commands in u-boot build image. 517 PBI commands can be used to configure SoC before it starts the execution. 518 Please refer doc/README.pblimage for more details 519 520 CONFIG_SPL_FSL_PBL 521 It adds a target to create boot binary having SPL binary in PBI format 522 concatenated with u-boot binary. 523 524 CONFIG_SYS_FSL_DDR_BE 525 Defines the DDR controller register space as Big Endian 526 527 CONFIG_SYS_FSL_DDR_LE 528 Defines the DDR controller register space as Little Endian 529 530 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 531 Physical address from the view of DDR controllers. It is the 532 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 533 it could be different for ARM SoCs. 534 535 CONFIG_SYS_FSL_DDR_INTLV_256B 536 DDR controller interleaving on 256-byte. This is a special 537 interleaving mode, handled by Dickens for Freescale layerscape 538 SoCs with ARM core. 539 540 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 541 Number of controllers used as main memory. 542 543 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 544 Number of controllers used for other than main memory. 545 546 CONFIG_SYS_FSL_HAS_DP_DDR 547 Defines the SoC has DP-DDR used for DPAA. 548 549 CONFIG_SYS_FSL_SEC_BE 550 Defines the SEC controller register space as Big Endian 551 552 CONFIG_SYS_FSL_SEC_LE 553 Defines the SEC controller register space as Little Endian 554 555- MIPS CPU options: 556 CONFIG_SYS_INIT_SP_OFFSET 557 558 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 559 pointer. This is needed for the temporary stack before 560 relocation. 561 562 CONFIG_SYS_MIPS_CACHE_MODE 563 564 Cache operation mode for the MIPS CPU. 565 See also arch/mips/include/asm/mipsregs.h. 566 Possible values are: 567 CONF_CM_CACHABLE_NO_WA 568 CONF_CM_CACHABLE_WA 569 CONF_CM_UNCACHED 570 CONF_CM_CACHABLE_NONCOHERENT 571 CONF_CM_CACHABLE_CE 572 CONF_CM_CACHABLE_COW 573 CONF_CM_CACHABLE_CUW 574 CONF_CM_CACHABLE_ACCELERATED 575 576 CONFIG_SYS_XWAY_EBU_BOOTCFG 577 578 Special option for Lantiq XWAY SoCs for booting from NOR flash. 579 See also arch/mips/cpu/mips32/start.S. 580 581 CONFIG_XWAY_SWAP_BYTES 582 583 Enable compilation of tools/xway-swap-bytes needed for Lantiq 584 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 585 be swapped if a flash programmer is used. 586 587- ARM options: 588 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 589 590 Select high exception vectors of the ARM core, e.g., do not 591 clear the V bit of the c1 register of CP15. 592 593 COUNTER_FREQUENCY 594 Generic timer clock source frequency. 595 596 COUNTER_FREQUENCY_REAL 597 Generic timer clock source frequency if the real clock is 598 different from COUNTER_FREQUENCY, and can only be determined 599 at run time. 600 601- Tegra SoC options: 602 CONFIG_TEGRA_SUPPORT_NON_SECURE 603 604 Support executing U-Boot in non-secure (NS) mode. Certain 605 impossible actions will be skipped if the CPU is in NS mode, 606 such as ARM architectural timer initialization. 607 608- Linux Kernel Interface: 609 CONFIG_CLOCKS_IN_MHZ 610 611 U-Boot stores all clock information in Hz 612 internally. For binary compatibility with older Linux 613 kernels (which expect the clocks passed in the 614 bd_info data to be in MHz) the environment variable 615 "clocks_in_mhz" can be defined so that U-Boot 616 converts clock data to MHZ before passing it to the 617 Linux kernel. 618 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 619 "clocks_in_mhz=1" is automatically included in the 620 default environment. 621 622 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 623 624 When transferring memsize parameter to Linux, some versions 625 expect it to be in bytes, others in MB. 626 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 627 628 CONFIG_OF_LIBFDT 629 630 New kernel versions are expecting firmware settings to be 631 passed using flattened device trees (based on open firmware 632 concepts). 633 634 CONFIG_OF_LIBFDT 635 * New libfdt-based support 636 * Adds the "fdt" command 637 * The bootm command automatically updates the fdt 638 639 OF_CPU - The proper name of the cpus node (only required for 640 MPC512X and MPC5xxx based boards). 641 OF_SOC - The proper name of the soc node (only required for 642 MPC512X and MPC5xxx based boards). 643 OF_TBCLK - The timebase frequency. 644 OF_STDOUT_PATH - The path to the console device 645 646 boards with QUICC Engines require OF_QE to set UCC MAC 647 addresses 648 649 CONFIG_OF_BOARD_SETUP 650 651 Board code has addition modification that it wants to make 652 to the flat device tree before handing it off to the kernel 653 654 CONFIG_OF_SYSTEM_SETUP 655 656 Other code has addition modification that it wants to make 657 to the flat device tree before handing it off to the kernel. 658 This causes ft_system_setup() to be called before booting 659 the kernel. 660 661 CONFIG_OF_IDE_FIXUP 662 663 U-Boot can detect if an IDE device is present or not. 664 If not, and this new config option is activated, U-Boot 665 removes the ATA node from the DTS before booting Linux, 666 so the Linux IDE driver does not probe the device and 667 crash. This is needed for buggy hardware (uc101) where 668 no pull down resistor is connected to the signal IDE5V_DD7. 669 670 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 671 672 This setting is mandatory for all boards that have only one 673 machine type and must be used to specify the machine type 674 number as it appears in the ARM machine registry 675 (see http://www.arm.linux.org.uk/developer/machines/). 676 Only boards that have multiple machine types supported 677 in a single configuration file and the machine type is 678 runtime discoverable, do not have to use this setting. 679 680- vxWorks boot parameters: 681 682 bootvx constructs a valid bootline using the following 683 environments variables: bootdev, bootfile, ipaddr, netmask, 684 serverip, gatewayip, hostname, othbootargs. 685 It loads the vxWorks image pointed bootfile. 686 687 Note: If a "bootargs" environment is defined, it will overwride 688 the defaults discussed just above. 689 690- Cache Configuration: 691 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 692 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 693 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 694 695- Cache Configuration for ARM: 696 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 697 controller 698 CONFIG_SYS_PL310_BASE - Physical base address of PL310 699 controller register space 700 701- Serial Ports: 702 CONFIG_PL010_SERIAL 703 704 Define this if you want support for Amba PrimeCell PL010 UARTs. 705 706 CONFIG_PL011_SERIAL 707 708 Define this if you want support for Amba PrimeCell PL011 UARTs. 709 710 CONFIG_PL011_CLOCK 711 712 If you have Amba PrimeCell PL011 UARTs, set this variable to 713 the clock speed of the UARTs. 714 715 CONFIG_PL01x_PORTS 716 717 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 718 define this to a list of base addresses for each (supported) 719 port. See e.g. include/configs/versatile.h 720 721 CONFIG_SERIAL_HW_FLOW_CONTROL 722 723 Define this variable to enable hw flow control in serial driver. 724 Current user of this option is drivers/serial/nsl16550.c driver 725 726- Console Interface: 727 Depending on board, define exactly one serial port 728 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 729 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 730 console by defining CONFIG_8xx_CONS_NONE 731 732 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 733 port routines must be defined elsewhere 734 (i.e. serial_init(), serial_getc(), ...) 735 736- Console Baudrate: 737 CONFIG_BAUDRATE - in bps 738 Select one of the baudrates listed in 739 CONFIG_SYS_BAUDRATE_TABLE, see below. 740 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 741 742- Console Rx buffer length 743 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 744 the maximum receive buffer length for the SMC. 745 This option is actual only for 82xx and 8xx possible. 746 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 747 must be defined, to setup the maximum idle timeout for 748 the SMC. 749 750- Autoboot Command: 751 CONFIG_BOOTCOMMAND 752 Only needed when CONFIG_BOOTDELAY is enabled; 753 define a command string that is automatically executed 754 when no character is read on the console interface 755 within "Boot Delay" after reset. 756 757 CONFIG_BOOTARGS 758 This can be used to pass arguments to the bootm 759 command. The value of CONFIG_BOOTARGS goes into the 760 environment value "bootargs". 761 762 CONFIG_RAMBOOT and CONFIG_NFSBOOT 763 The value of these goes into the environment as 764 "ramboot" and "nfsboot" respectively, and can be used 765 as a convenience, when switching between booting from 766 RAM and NFS. 767 768- Bootcount: 769 CONFIG_BOOTCOUNT_LIMIT 770 Implements a mechanism for detecting a repeating reboot 771 cycle, see: 772 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 773 774 CONFIG_BOOTCOUNT_ENV 775 If no softreset save registers are found on the hardware 776 "bootcount" is stored in the environment. To prevent a 777 saveenv on all reboots, the environment variable 778 "upgrade_available" is used. If "upgrade_available" is 779 0, "bootcount" is always 0, if "upgrade_available" is 780 1 "bootcount" is incremented in the environment. 781 So the Userspace Applikation must set the "upgrade_available" 782 and "bootcount" variable to 0, if a boot was successfully. 783 784- Pre-Boot Commands: 785 CONFIG_PREBOOT 786 787 When this option is #defined, the existence of the 788 environment variable "preboot" will be checked 789 immediately before starting the CONFIG_BOOTDELAY 790 countdown and/or running the auto-boot command resp. 791 entering interactive mode. 792 793 This feature is especially useful when "preboot" is 794 automatically generated or modified. For an example 795 see the LWMON board specific code: here "preboot" is 796 modified when the user holds down a certain 797 combination of keys on the (special) keyboard when 798 booting the systems 799 800- Serial Download Echo Mode: 801 CONFIG_LOADS_ECHO 802 If defined to 1, all characters received during a 803 serial download (using the "loads" command) are 804 echoed back. This might be needed by some terminal 805 emulations (like "cu"), but may as well just take 806 time on others. This setting #define's the initial 807 value of the "loads_echo" environment variable. 808 809- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 810 CONFIG_KGDB_BAUDRATE 811 Select one of the baudrates listed in 812 CONFIG_SYS_BAUDRATE_TABLE, see below. 813 814- Monitor Functions: 815 Monitor commands can be included or excluded 816 from the build by using the #include files 817 <config_cmd_all.h> and #undef'ing unwanted 818 commands, or adding #define's for wanted commands. 819 820 The default command configuration includes all commands 821 except those marked below with a "*". 822 823 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 824 CONFIG_CMD_ASKENV * ask for env variable 825 CONFIG_CMD_BDI bdinfo 826 CONFIG_CMD_BOOTD bootd 827 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 828 CONFIG_CMD_CACHE * icache, dcache 829 CONFIG_CMD_CONSOLE coninfo 830 CONFIG_CMD_CRC32 * crc32 831 CONFIG_CMD_DHCP * DHCP support 832 CONFIG_CMD_DIAG * Diagnostics 833 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 834 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 835 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 836 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 837 CONFIG_CMD_DTT * Digital Therm and Thermostat 838 CONFIG_CMD_ECHO echo arguments 839 CONFIG_CMD_EDITENV edit env variable 840 CONFIG_CMD_EEPROM * EEPROM read/write support 841 CONFIG_CMD_EEPROM_LAYOUT* EEPROM layout aware commands 842 CONFIG_CMD_ELF * bootelf, bootvx 843 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 844 CONFIG_CMD_ENV_FLAGS * display details about env flags 845 CONFIG_CMD_ENV_EXISTS * check existence of env variable 846 CONFIG_CMD_EXPORTENV * export the environment 847 CONFIG_CMD_EXT2 * ext2 command support 848 CONFIG_CMD_EXT4 * ext4 command support 849 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 850 that work for multiple fs types 851 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 852 CONFIG_CMD_SAVEENV saveenv 853 CONFIG_CMD_FDC * Floppy Disk Support 854 CONFIG_CMD_FAT * FAT command support 855 CONFIG_CMD_FLASH flinfo, erase, protect 856 CONFIG_CMD_FPGA FPGA device initialization support 857 CONFIG_CMD_FUSE * Device fuse support 858 CONFIG_CMD_GETTIME * Get time since boot 859 CONFIG_CMD_GO * the 'go' command (exec code) 860 CONFIG_CMD_GREPENV * search environment 861 CONFIG_CMD_HASH * calculate hash / digest 862 CONFIG_CMD_I2C * I2C serial bus support 863 CONFIG_CMD_IDE * IDE harddisk support 864 CONFIG_CMD_IMI iminfo 865 CONFIG_CMD_IMLS List all images found in NOR flash 866 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 867 CONFIG_CMD_IMMAP * IMMR dump support 868 CONFIG_CMD_IOTRACE * I/O tracing for debugging 869 CONFIG_CMD_IMPORTENV * import an environment 870 CONFIG_CMD_INI * import data from an ini file into the env 871 CONFIG_CMD_IRQ * irqinfo 872 CONFIG_CMD_ITEST Integer/string test of 2 values 873 CONFIG_CMD_JFFS2 * JFFS2 Support 874 CONFIG_CMD_KGDB * kgdb 875 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 876 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 877 (169.254.*.*) 878 CONFIG_CMD_LOADB loadb 879 CONFIG_CMD_LOADS loads 880 CONFIG_CMD_MD5SUM * print md5 message digest 881 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 882 CONFIG_CMD_MEMINFO * Display detailed memory information 883 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 884 loop, loopw 885 CONFIG_CMD_MEMTEST * mtest 886 CONFIG_CMD_MISC Misc functions like sleep etc 887 CONFIG_CMD_MMC * MMC memory mapped support 888 CONFIG_CMD_MII * MII utility commands 889 CONFIG_CMD_MTDPARTS * MTD partition support 890 CONFIG_CMD_NAND * NAND support 891 CONFIG_CMD_NET bootp, tftpboot, rarpboot 892 CONFIG_CMD_NFS NFS support 893 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 894 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 895 CONFIG_CMD_PCI * pciinfo 896 CONFIG_CMD_PCMCIA * PCMCIA support 897 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 898 host 899 CONFIG_CMD_PORTIO * Port I/O 900 CONFIG_CMD_READ * Read raw data from partition 901 CONFIG_CMD_REGINFO * Register dump 902 CONFIG_CMD_RUN run command in env variable 903 CONFIG_CMD_SANDBOX * sb command to access sandbox features 904 CONFIG_CMD_SAVES * save S record dump 905 CONFIG_SCSI * SCSI Support 906 CONFIG_CMD_SDRAM * print SDRAM configuration information 907 (requires CONFIG_CMD_I2C) 908 CONFIG_CMD_SETGETDCR Support for DCR Register access 909 (4xx only) 910 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 911 CONFIG_CMD_SHA1SUM * print sha1 memory digest 912 (requires CONFIG_CMD_MEMORY) 913 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 914 CONFIG_CMD_SOURCE "source" command Support 915 CONFIG_CMD_SPI * SPI serial bus support 916 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 917 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 918 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 919 CONFIG_CMD_TIMER * access to the system tick timer 920 CONFIG_CMD_USB * USB support 921 CONFIG_CMD_CDP * Cisco Discover Protocol support 922 CONFIG_CMD_MFSL * Microblaze FSL support 923 CONFIG_CMD_XIMG Load part of Multi Image 924 CONFIG_CMD_UUID * Generate random UUID or GUID string 925 926 EXAMPLE: If you want all functions except of network 927 support you can write: 928 929 #include "config_cmd_all.h" 930 #undef CONFIG_CMD_NET 931 932 Other Commands: 933 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 934 935 Note: Don't enable the "icache" and "dcache" commands 936 (configuration option CONFIG_CMD_CACHE) unless you know 937 what you (and your U-Boot users) are doing. Data 938 cache cannot be enabled on systems like the 8xx or 939 8260 (where accesses to the IMMR region must be 940 uncached), and it cannot be disabled on all other 941 systems where we (mis-) use the data cache to hold an 942 initial stack and some data. 943 944 945 XXX - this list needs to get updated! 946 947- Removal of commands 948 If no commands are needed to boot, you can disable 949 CONFIG_CMDLINE to remove them. In this case, the command line 950 will not be available, and when U-Boot wants to execute the 951 boot command (on start-up) it will call board_run_command() 952 instead. This can reduce image size significantly for very 953 simple boot procedures. 954 955- Regular expression support: 956 CONFIG_REGEX 957 If this variable is defined, U-Boot is linked against 958 the SLRE (Super Light Regular Expression) library, 959 which adds regex support to some commands, as for 960 example "env grep" and "setexpr". 961 962- Device tree: 963 CONFIG_OF_CONTROL 964 If this variable is defined, U-Boot will use a device tree 965 to configure its devices, instead of relying on statically 966 compiled #defines in the board file. This option is 967 experimental and only available on a few boards. The device 968 tree is available in the global data as gd->fdt_blob. 969 970 U-Boot needs to get its device tree from somewhere. This can 971 be done using one of the three options below: 972 973 CONFIG_OF_EMBED 974 If this variable is defined, U-Boot will embed a device tree 975 binary in its image. This device tree file should be in the 976 board directory and called <soc>-<board>.dts. The binary file 977 is then picked up in board_init_f() and made available through 978 the global data structure as gd->blob. 979 980 CONFIG_OF_SEPARATE 981 If this variable is defined, U-Boot will build a device tree 982 binary. It will be called u-boot.dtb. Architecture-specific 983 code will locate it at run-time. Generally this works by: 984 985 cat u-boot.bin u-boot.dtb >image.bin 986 987 and in fact, U-Boot does this for you, creating a file called 988 u-boot-dtb.bin which is useful in the common case. You can 989 still use the individual files if you need something more 990 exotic. 991 992 CONFIG_OF_BOARD 993 If this variable is defined, U-Boot will use the device tree 994 provided by the board at runtime instead of embedding one with 995 the image. Only boards defining board_fdt_blob_setup() support 996 this option (see include/fdtdec.h file). 997 998- Watchdog: 999 CONFIG_WATCHDOG 1000 If this variable is defined, it enables watchdog 1001 support for the SoC. There must be support in the SoC 1002 specific code for a watchdog. For the 8xx and 8260 1003 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1004 register. When supported for a specific SoC is 1005 available, then no further board specific code should 1006 be needed to use it. 1007 1008 CONFIG_HW_WATCHDOG 1009 When using a watchdog circuitry external to the used 1010 SoC, then define this variable and provide board 1011 specific code for the "hw_watchdog_reset" function. 1012 1013 CONFIG_AT91_HW_WDT_TIMEOUT 1014 specify the timeout in seconds. default 2 seconds. 1015 1016- U-Boot Version: 1017 CONFIG_VERSION_VARIABLE 1018 If this variable is defined, an environment variable 1019 named "ver" is created by U-Boot showing the U-Boot 1020 version as printed by the "version" command. 1021 Any change to this variable will be reverted at the 1022 next reset. 1023 1024- Real-Time Clock: 1025 1026 When CONFIG_CMD_DATE is selected, the type of the RTC 1027 has to be selected, too. Define exactly one of the 1028 following options: 1029 1030 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1031 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1032 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1033 CONFIG_RTC_MC146818 - use MC146818 RTC 1034 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1035 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1036 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1037 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1038 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1039 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1040 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1041 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1042 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1043 RV3029 RTC. 1044 1045 Note that if the RTC uses I2C, then the I2C interface 1046 must also be configured. See I2C Support, below. 1047 1048- GPIO Support: 1049 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1050 1051 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1052 chip-ngpio pairs that tell the PCA953X driver the number of 1053 pins supported by a particular chip. 1054 1055 Note that if the GPIO device uses I2C, then the I2C interface 1056 must also be configured. See I2C Support, below. 1057 1058- I/O tracing: 1059 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1060 accesses and can checksum them or write a list of them out 1061 to memory. See the 'iotrace' command for details. This is 1062 useful for testing device drivers since it can confirm that 1063 the driver behaves the same way before and after a code 1064 change. Currently this is supported on sandbox and arm. To 1065 add support for your architecture, add '#include <iotrace.h>' 1066 to the bottom of arch/<arch>/include/asm/io.h and test. 1067 1068 Example output from the 'iotrace stats' command is below. 1069 Note that if the trace buffer is exhausted, the checksum will 1070 still continue to operate. 1071 1072 iotrace is enabled 1073 Start: 10000000 (buffer start address) 1074 Size: 00010000 (buffer size) 1075 Offset: 00000120 (current buffer offset) 1076 Output: 10000120 (start + offset) 1077 Count: 00000018 (number of trace records) 1078 CRC32: 9526fb66 (CRC32 of all trace records) 1079 1080- Timestamp Support: 1081 1082 When CONFIG_TIMESTAMP is selected, the timestamp 1083 (date and time) of an image is printed by image 1084 commands like bootm or iminfo. This option is 1085 automatically enabled when you select CONFIG_CMD_DATE . 1086 1087- Partition Labels (disklabels) Supported: 1088 Zero or more of the following: 1089 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1090 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1091 Intel architecture, USB sticks, etc. 1092 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1093 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1094 bootloader. Note 2TB partition limit; see 1095 disk/part_efi.c 1096 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1097 1098 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1099 CONFIG_SCSI) you must configure support for at 1100 least one non-MTD partition type as well. 1101 1102- IDE Reset method: 1103 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1104 board configurations files but used nowhere! 1105 1106 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1107 be performed by calling the function 1108 ide_set_reset(int reset) 1109 which has to be defined in a board specific file 1110 1111- ATAPI Support: 1112 CONFIG_ATAPI 1113 1114 Set this to enable ATAPI support. 1115 1116- LBA48 Support 1117 CONFIG_LBA48 1118 1119 Set this to enable support for disks larger than 137GB 1120 Also look at CONFIG_SYS_64BIT_LBA. 1121 Whithout these , LBA48 support uses 32bit variables and will 'only' 1122 support disks up to 2.1TB. 1123 1124 CONFIG_SYS_64BIT_LBA: 1125 When enabled, makes the IDE subsystem use 64bit sector addresses. 1126 Default is 32bit. 1127 1128- SCSI Support: 1129 At the moment only there is only support for the 1130 SYM53C8XX SCSI controller; define 1131 CONFIG_SCSI_SYM53C8XX to enable it. 1132 1133 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1134 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1135 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1136 maximum numbers of LUNs, SCSI ID's and target 1137 devices. 1138 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1139 1140 The environment variable 'scsidevs' is set to the number of 1141 SCSI devices found during the last scan. 1142 1143- NETWORK Support (PCI): 1144 CONFIG_E1000 1145 Support for Intel 8254x/8257x gigabit chips. 1146 1147 CONFIG_E1000_SPI 1148 Utility code for direct access to the SPI bus on Intel 8257x. 1149 This does not do anything useful unless you set at least one 1150 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1151 1152 CONFIG_E1000_SPI_GENERIC 1153 Allow generic access to the SPI bus on the Intel 8257x, for 1154 example with the "sspi" command. 1155 1156 CONFIG_CMD_E1000 1157 Management command for E1000 devices. When used on devices 1158 with SPI support you can reprogram the EEPROM from U-Boot. 1159 1160 CONFIG_EEPRO100 1161 Support for Intel 82557/82559/82559ER chips. 1162 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1163 write routine for first time initialisation. 1164 1165 CONFIG_TULIP 1166 Support for Digital 2114x chips. 1167 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1168 modem chip initialisation (KS8761/QS6611). 1169 1170 CONFIG_NATSEMI 1171 Support for National dp83815 chips. 1172 1173 CONFIG_NS8382X 1174 Support for National dp8382[01] gigabit chips. 1175 1176- NETWORK Support (other): 1177 1178 CONFIG_DRIVER_AT91EMAC 1179 Support for AT91RM9200 EMAC. 1180 1181 CONFIG_RMII 1182 Define this to use reduced MII inteface 1183 1184 CONFIG_DRIVER_AT91EMAC_QUIET 1185 If this defined, the driver is quiet. 1186 The driver doen't show link status messages. 1187 1188 CONFIG_CALXEDA_XGMAC 1189 Support for the Calxeda XGMAC device 1190 1191 CONFIG_LAN91C96 1192 Support for SMSC's LAN91C96 chips. 1193 1194 CONFIG_LAN91C96_USE_32_BIT 1195 Define this to enable 32 bit addressing 1196 1197 CONFIG_SMC91111 1198 Support for SMSC's LAN91C111 chip 1199 1200 CONFIG_SMC91111_BASE 1201 Define this to hold the physical address 1202 of the device (I/O space) 1203 1204 CONFIG_SMC_USE_32_BIT 1205 Define this if data bus is 32 bits 1206 1207 CONFIG_SMC_USE_IOFUNCS 1208 Define this to use i/o functions instead of macros 1209 (some hardware wont work with macros) 1210 1211 CONFIG_DRIVER_TI_EMAC 1212 Support for davinci emac 1213 1214 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1215 Define this if you have more then 3 PHYs. 1216 1217 CONFIG_FTGMAC100 1218 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1219 1220 CONFIG_FTGMAC100_EGIGA 1221 Define this to use GE link update with gigabit PHY. 1222 Define this if FTGMAC100 is connected to gigabit PHY. 1223 If your system has 10/100 PHY only, it might not occur 1224 wrong behavior. Because PHY usually return timeout or 1225 useless data when polling gigabit status and gigabit 1226 control registers. This behavior won't affect the 1227 correctnessof 10/100 link speed update. 1228 1229 CONFIG_SMC911X 1230 Support for SMSC's LAN911x and LAN921x chips 1231 1232 CONFIG_SMC911X_BASE 1233 Define this to hold the physical address 1234 of the device (I/O space) 1235 1236 CONFIG_SMC911X_32_BIT 1237 Define this if data bus is 32 bits 1238 1239 CONFIG_SMC911X_16_BIT 1240 Define this if data bus is 16 bits. If your processor 1241 automatically converts one 32 bit word to two 16 bit 1242 words you may also try CONFIG_SMC911X_32_BIT. 1243 1244 CONFIG_SH_ETHER 1245 Support for Renesas on-chip Ethernet controller 1246 1247 CONFIG_SH_ETHER_USE_PORT 1248 Define the number of ports to be used 1249 1250 CONFIG_SH_ETHER_PHY_ADDR 1251 Define the ETH PHY's address 1252 1253 CONFIG_SH_ETHER_CACHE_WRITEBACK 1254 If this option is set, the driver enables cache flush. 1255 1256- PWM Support: 1257 CONFIG_PWM_IMX 1258 Support for PWM module on the imx6. 1259 1260- TPM Support: 1261 CONFIG_TPM 1262 Support TPM devices. 1263 1264 CONFIG_TPM_TIS_INFINEON 1265 Support for Infineon i2c bus TPM devices. Only one device 1266 per system is supported at this time. 1267 1268 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1269 Define the burst count bytes upper limit 1270 1271 CONFIG_TPM_ST33ZP24 1272 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1273 1274 CONFIG_TPM_ST33ZP24_I2C 1275 Support for STMicroelectronics ST33ZP24 I2C devices. 1276 Requires TPM_ST33ZP24 and I2C. 1277 1278 CONFIG_TPM_ST33ZP24_SPI 1279 Support for STMicroelectronics ST33ZP24 SPI devices. 1280 Requires TPM_ST33ZP24 and SPI. 1281 1282 CONFIG_TPM_ATMEL_TWI 1283 Support for Atmel TWI TPM device. Requires I2C support. 1284 1285 CONFIG_TPM_TIS_LPC 1286 Support for generic parallel port TPM devices. Only one device 1287 per system is supported at this time. 1288 1289 CONFIG_TPM_TIS_BASE_ADDRESS 1290 Base address where the generic TPM device is mapped 1291 to. Contemporary x86 systems usually map it at 1292 0xfed40000. 1293 1294 CONFIG_CMD_TPM 1295 Add tpm monitor functions. 1296 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1297 provides monitor access to authorized functions. 1298 1299 CONFIG_TPM 1300 Define this to enable the TPM support library which provides 1301 functional interfaces to some TPM commands. 1302 Requires support for a TPM device. 1303 1304 CONFIG_TPM_AUTH_SESSIONS 1305 Define this to enable authorized functions in the TPM library. 1306 Requires CONFIG_TPM and CONFIG_SHA1. 1307 1308- USB Support: 1309 At the moment only the UHCI host controller is 1310 supported (PIP405, MIP405, MPC5200); define 1311 CONFIG_USB_UHCI to enable it. 1312 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1313 and define CONFIG_USB_STORAGE to enable the USB 1314 storage devices. 1315 Note: 1316 Supported are USB Keyboards and USB Floppy drives 1317 (TEAC FD-05PUB). 1318 MPC5200 USB requires additional defines: 1319 CONFIG_USB_CLOCK 1320 for 528 MHz Clock: 0x0001bbbb 1321 CONFIG_PSC3_USB 1322 for USB on PSC3 1323 CONFIG_USB_CONFIG 1324 for differential drivers: 0x00001000 1325 for single ended drivers: 0x00005000 1326 for differential drivers on PSC3: 0x00000100 1327 for single ended drivers on PSC3: 0x00004100 1328 CONFIG_SYS_USB_EVENT_POLL 1329 May be defined to allow interrupt polling 1330 instead of using asynchronous interrupts 1331 1332 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1333 txfilltuning field in the EHCI controller on reset. 1334 1335 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1336 HW module registers. 1337 1338- USB Device: 1339 Define the below if you wish to use the USB console. 1340 Once firmware is rebuilt from a serial console issue the 1341 command "setenv stdin usbtty; setenv stdout usbtty" and 1342 attach your USB cable. The Unix command "dmesg" should print 1343 it has found a new device. The environment variable usbtty 1344 can be set to gserial or cdc_acm to enable your device to 1345 appear to a USB host as a Linux gserial device or a 1346 Common Device Class Abstract Control Model serial device. 1347 If you select usbtty = gserial you should be able to enumerate 1348 a Linux host by 1349 # modprobe usbserial vendor=0xVendorID product=0xProductID 1350 else if using cdc_acm, simply setting the environment 1351 variable usbtty to be cdc_acm should suffice. The following 1352 might be defined in YourBoardName.h 1353 1354 CONFIG_USB_DEVICE 1355 Define this to build a UDC device 1356 1357 CONFIG_USB_TTY 1358 Define this to have a tty type of device available to 1359 talk to the UDC device 1360 1361 CONFIG_USBD_HS 1362 Define this to enable the high speed support for usb 1363 device and usbtty. If this feature is enabled, a routine 1364 int is_usbd_high_speed(void) 1365 also needs to be defined by the driver to dynamically poll 1366 whether the enumeration has succeded at high speed or full 1367 speed. 1368 1369 CONFIG_SYS_CONSOLE_IS_IN_ENV 1370 Define this if you want stdin, stdout &/or stderr to 1371 be set to usbtty. 1372 1373 mpc8xx: 1374 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1375 Derive USB clock from external clock "blah" 1376 - CONFIG_SYS_USB_EXTC_CLK 0x02 1377 1378 If you have a USB-IF assigned VendorID then you may wish to 1379 define your own vendor specific values either in BoardName.h 1380 or directly in usbd_vendor_info.h. If you don't define 1381 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1382 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1383 should pretend to be a Linux device to it's target host. 1384 1385 CONFIG_USBD_MANUFACTURER 1386 Define this string as the name of your company for 1387 - CONFIG_USBD_MANUFACTURER "my company" 1388 1389 CONFIG_USBD_PRODUCT_NAME 1390 Define this string as the name of your product 1391 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1392 1393 CONFIG_USBD_VENDORID 1394 Define this as your assigned Vendor ID from the USB 1395 Implementors Forum. This *must* be a genuine Vendor ID 1396 to avoid polluting the USB namespace. 1397 - CONFIG_USBD_VENDORID 0xFFFF 1398 1399 CONFIG_USBD_PRODUCTID 1400 Define this as the unique Product ID 1401 for your device 1402 - CONFIG_USBD_PRODUCTID 0xFFFF 1403 1404- ULPI Layer Support: 1405 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1406 the generic ULPI layer. The generic layer accesses the ULPI PHY 1407 via the platform viewport, so you need both the genric layer and 1408 the viewport enabled. Currently only Chipidea/ARC based 1409 viewport is supported. 1410 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1411 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1412 If your ULPI phy needs a different reference clock than the 1413 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1414 the appropriate value in Hz. 1415 1416- MMC Support: 1417 The MMC controller on the Intel PXA is supported. To 1418 enable this define CONFIG_MMC. The MMC can be 1419 accessed from the boot prompt by mapping the device 1420 to physical memory similar to flash. Command line is 1421 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1422 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1423 1424 CONFIG_SH_MMCIF 1425 Support for Renesas on-chip MMCIF controller 1426 1427 CONFIG_SH_MMCIF_ADDR 1428 Define the base address of MMCIF registers 1429 1430 CONFIG_SH_MMCIF_CLK 1431 Define the clock frequency for MMCIF 1432 1433 CONFIG_SUPPORT_EMMC_BOOT 1434 Enable some additional features of the eMMC boot partitions. 1435 1436 CONFIG_SUPPORT_EMMC_RPMB 1437 Enable the commands for reading, writing and programming the 1438 key for the Replay Protection Memory Block partition in eMMC. 1439 1440- USB Device Firmware Update (DFU) class support: 1441 CONFIG_USB_FUNCTION_DFU 1442 This enables the USB portion of the DFU USB class 1443 1444 CONFIG_CMD_DFU 1445 This enables the command "dfu" which is used to have 1446 U-Boot create a DFU class device via USB. This command 1447 requires that the "dfu_alt_info" environment variable be 1448 set and define the alt settings to expose to the host. 1449 1450 CONFIG_DFU_MMC 1451 This enables support for exposing (e)MMC devices via DFU. 1452 1453 CONFIG_DFU_NAND 1454 This enables support for exposing NAND devices via DFU. 1455 1456 CONFIG_DFU_RAM 1457 This enables support for exposing RAM via DFU. 1458 Note: DFU spec refer to non-volatile memory usage, but 1459 allow usages beyond the scope of spec - here RAM usage, 1460 one that would help mostly the developer. 1461 1462 CONFIG_SYS_DFU_DATA_BUF_SIZE 1463 Dfu transfer uses a buffer before writing data to the 1464 raw storage device. Make the size (in bytes) of this buffer 1465 configurable. The size of this buffer is also configurable 1466 through the "dfu_bufsiz" environment variable. 1467 1468 CONFIG_SYS_DFU_MAX_FILE_SIZE 1469 When updating files rather than the raw storage device, 1470 we use a static buffer to copy the file into and then write 1471 the buffer once we've been given the whole file. Define 1472 this to the maximum filesize (in bytes) for the buffer. 1473 Default is 4 MiB if undefined. 1474 1475 DFU_DEFAULT_POLL_TIMEOUT 1476 Poll timeout [ms], is the timeout a device can send to the 1477 host. The host must wait for this timeout before sending 1478 a subsequent DFU_GET_STATUS request to the device. 1479 1480 DFU_MANIFEST_POLL_TIMEOUT 1481 Poll timeout [ms], which the device sends to the host when 1482 entering dfuMANIFEST state. Host waits this timeout, before 1483 sending again an USB request to the device. 1484 1485- USB Device Android Fastboot support: 1486 CONFIG_USB_FUNCTION_FASTBOOT 1487 This enables the USB part of the fastboot gadget 1488 1489 CONFIG_CMD_FASTBOOT 1490 This enables the command "fastboot" which enables the Android 1491 fastboot mode for the platform's USB device. Fastboot is a USB 1492 protocol for downloading images, flashing and device control 1493 used on Android devices. 1494 See doc/README.android-fastboot for more information. 1495 1496 CONFIG_ANDROID_BOOT_IMAGE 1497 This enables support for booting images which use the Android 1498 image format header. 1499 1500 CONFIG_FASTBOOT_BUF_ADDR 1501 The fastboot protocol requires a large memory buffer for 1502 downloads. Define this to the starting RAM address to use for 1503 downloaded images. 1504 1505 CONFIG_FASTBOOT_BUF_SIZE 1506 The fastboot protocol requires a large memory buffer for 1507 downloads. This buffer should be as large as possible for a 1508 platform. Define this to the size available RAM for fastboot. 1509 1510 CONFIG_FASTBOOT_FLASH 1511 The fastboot protocol includes a "flash" command for writing 1512 the downloaded image to a non-volatile storage device. Define 1513 this to enable the "fastboot flash" command. 1514 1515 CONFIG_FASTBOOT_FLASH_MMC_DEV 1516 The fastboot "flash" command requires additional information 1517 regarding the non-volatile storage device. Define this to 1518 the eMMC device that fastboot should use to store the image. 1519 1520 CONFIG_FASTBOOT_GPT_NAME 1521 The fastboot "flash" command supports writing the downloaded 1522 image to the Protective MBR and the Primary GUID Partition 1523 Table. (Additionally, this downloaded image is post-processed 1524 to generate and write the Backup GUID Partition Table.) 1525 This occurs when the specified "partition name" on the 1526 "fastboot flash" command line matches this value. 1527 The default is "gpt" if undefined. 1528 1529 CONFIG_FASTBOOT_MBR_NAME 1530 The fastboot "flash" command supports writing the downloaded 1531 image to DOS MBR. 1532 This occurs when the "partition name" specified on the 1533 "fastboot flash" command line matches this value. 1534 If not defined the default value "mbr" is used. 1535 1536- Journaling Flash filesystem support: 1537 CONFIG_JFFS2_NAND 1538 Define these for a default partition on a NAND device 1539 1540 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1541 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1542 Define these for a default partition on a NOR device 1543 1544- FAT(File Allocation Table) filesystem write function support: 1545 CONFIG_FAT_WRITE 1546 1547 Define this to enable support for saving memory data as a 1548 file in FAT formatted partition. 1549 1550 This will also enable the command "fatwrite" enabling the 1551 user to write files to FAT. 1552 1553- FAT(File Allocation Table) filesystem cluster size: 1554 CONFIG_FS_FAT_MAX_CLUSTSIZE 1555 1556 Define the max cluster size for fat operations else 1557 a default value of 65536 will be defined. 1558 1559- Keyboard Support: 1560 See Kconfig help for available keyboard drivers. 1561 1562 CONFIG_KEYBOARD 1563 1564 Define this to enable a custom keyboard support. 1565 This simply calls drv_keyboard_init() which must be 1566 defined in your board-specific files. This option is deprecated 1567 and is only used by novena. For new boards, use driver model 1568 instead. 1569 1570- Video support: 1571 CONFIG_FSL_DIU_FB 1572 Enable the Freescale DIU video driver. Reference boards for 1573 SOCs that have a DIU should define this macro to enable DIU 1574 support, and should also define these other macros: 1575 1576 CONFIG_SYS_DIU_ADDR 1577 CONFIG_VIDEO 1578 CONFIG_CFB_CONSOLE 1579 CONFIG_VIDEO_SW_CURSOR 1580 CONFIG_VGA_AS_SINGLE_DEVICE 1581 CONFIG_VIDEO_LOGO 1582 CONFIG_VIDEO_BMP_LOGO 1583 1584 The DIU driver will look for the 'video-mode' environment 1585 variable, and if defined, enable the DIU as a console during 1586 boot. See the documentation file doc/README.video for a 1587 description of this variable. 1588 1589- LCD Support: CONFIG_LCD 1590 1591 Define this to enable LCD support (for output to LCD 1592 display); also select one of the supported displays 1593 by defining one of these: 1594 1595 CONFIG_ATMEL_LCD: 1596 1597 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1598 1599 CONFIG_NEC_NL6448AC33: 1600 1601 NEC NL6448AC33-18. Active, color, single scan. 1602 1603 CONFIG_NEC_NL6448BC20 1604 1605 NEC NL6448BC20-08. 6.5", 640x480. 1606 Active, color, single scan. 1607 1608 CONFIG_NEC_NL6448BC33_54 1609 1610 NEC NL6448BC33-54. 10.4", 640x480. 1611 Active, color, single scan. 1612 1613 CONFIG_SHARP_16x9 1614 1615 Sharp 320x240. Active, color, single scan. 1616 It isn't 16x9, and I am not sure what it is. 1617 1618 CONFIG_SHARP_LQ64D341 1619 1620 Sharp LQ64D341 display, 640x480. 1621 Active, color, single scan. 1622 1623 CONFIG_HLD1045 1624 1625 HLD1045 display, 640x480. 1626 Active, color, single scan. 1627 1628 CONFIG_OPTREX_BW 1629 1630 Optrex CBL50840-2 NF-FW 99 22 M5 1631 or 1632 Hitachi LMG6912RPFC-00T 1633 or 1634 Hitachi SP14Q002 1635 1636 320x240. Black & white. 1637 1638 CONFIG_LCD_ALIGNMENT 1639 1640 Normally the LCD is page-aligned (typically 4KB). If this is 1641 defined then the LCD will be aligned to this value instead. 1642 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1643 here, since it is cheaper to change data cache settings on 1644 a per-section basis. 1645 1646 1647 CONFIG_LCD_ROTATION 1648 1649 Sometimes, for example if the display is mounted in portrait 1650 mode or even if it's mounted landscape but rotated by 180degree, 1651 we need to rotate our content of the display relative to the 1652 framebuffer, so that user can read the messages which are 1653 printed out. 1654 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1655 initialized with a given rotation from "vl_rot" out of 1656 "vidinfo_t" which is provided by the board specific code. 1657 The value for vl_rot is coded as following (matching to 1658 fbcon=rotate:<n> linux-kernel commandline): 1659 0 = no rotation respectively 0 degree 1660 1 = 90 degree rotation 1661 2 = 180 degree rotation 1662 3 = 270 degree rotation 1663 1664 If CONFIG_LCD_ROTATION is not defined, the console will be 1665 initialized with 0degree rotation. 1666 1667 CONFIG_LCD_BMP_RLE8 1668 1669 Support drawing of RLE8-compressed bitmaps on the LCD. 1670 1671 CONFIG_I2C_EDID 1672 1673 Enables an 'i2c edid' command which can read EDID 1674 information over I2C from an attached LCD display. 1675 1676- Splash Screen Support: CONFIG_SPLASH_SCREEN 1677 1678 If this option is set, the environment is checked for 1679 a variable "splashimage". If found, the usual display 1680 of logo, copyright and system information on the LCD 1681 is suppressed and the BMP image at the address 1682 specified in "splashimage" is loaded instead. The 1683 console is redirected to the "nulldev", too. This 1684 allows for a "silent" boot where a splash screen is 1685 loaded very quickly after power-on. 1686 1687 CONFIG_SPLASHIMAGE_GUARD 1688 1689 If this option is set, then U-Boot will prevent the environment 1690 variable "splashimage" from being set to a problematic address 1691 (see doc/README.displaying-bmps). 1692 This option is useful for targets where, due to alignment 1693 restrictions, an improperly aligned BMP image will cause a data 1694 abort. If you think you will not have problems with unaligned 1695 accesses (for example because your toolchain prevents them) 1696 there is no need to set this option. 1697 1698 CONFIG_SPLASH_SCREEN_ALIGN 1699 1700 If this option is set the splash image can be freely positioned 1701 on the screen. Environment variable "splashpos" specifies the 1702 position as "x,y". If a positive number is given it is used as 1703 number of pixel from left/top. If a negative number is given it 1704 is used as number of pixel from right/bottom. You can also 1705 specify 'm' for centering the image. 1706 1707 Example: 1708 setenv splashpos m,m 1709 => image at center of screen 1710 1711 setenv splashpos 30,20 1712 => image at x = 30 and y = 20 1713 1714 setenv splashpos -10,m 1715 => vertically centered image 1716 at x = dspWidth - bmpWidth - 9 1717 1718- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1719 1720 If this option is set, additionally to standard BMP 1721 images, gzipped BMP images can be displayed via the 1722 splashscreen support or the bmp command. 1723 1724- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1725 1726 If this option is set, 8-bit RLE compressed BMP images 1727 can be displayed via the splashscreen support or the 1728 bmp command. 1729 1730- Compression support: 1731 CONFIG_GZIP 1732 1733 Enabled by default to support gzip compressed images. 1734 1735 CONFIG_BZIP2 1736 1737 If this option is set, support for bzip2 compressed 1738 images is included. If not, only uncompressed and gzip 1739 compressed images are supported. 1740 1741 NOTE: the bzip2 algorithm requires a lot of RAM, so 1742 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1743 be at least 4MB. 1744 1745 CONFIG_LZMA 1746 1747 If this option is set, support for lzma compressed 1748 images is included. 1749 1750 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1751 requires an amount of dynamic memory that is given by the 1752 formula: 1753 1754 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1755 1756 Where lc and lp stand for, respectively, Literal context bits 1757 and Literal pos bits. 1758 1759 This value is upper-bounded by 14MB in the worst case. Anyway, 1760 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1761 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1762 a very small buffer. 1763 1764 Use the lzmainfo tool to determinate the lc and lp values and 1765 then calculate the amount of needed dynamic memory (ensuring 1766 the appropriate CONFIG_SYS_MALLOC_LEN value). 1767 1768 CONFIG_LZO 1769 1770 If this option is set, support for LZO compressed images 1771 is included. 1772 1773- MII/PHY support: 1774 CONFIG_PHY_ADDR 1775 1776 The address of PHY on MII bus. 1777 1778 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1779 1780 The clock frequency of the MII bus 1781 1782 CONFIG_PHY_GIGE 1783 1784 If this option is set, support for speed/duplex 1785 detection of gigabit PHY is included. 1786 1787 CONFIG_PHY_RESET_DELAY 1788 1789 Some PHY like Intel LXT971A need extra delay after 1790 reset before any MII register access is possible. 1791 For such PHY, set this option to the usec delay 1792 required. (minimum 300usec for LXT971A) 1793 1794 CONFIG_PHY_CMD_DELAY (ppc4xx) 1795 1796 Some PHY like Intel LXT971A need extra delay after 1797 command issued before MII status register can be read 1798 1799- IP address: 1800 CONFIG_IPADDR 1801 1802 Define a default value for the IP address to use for 1803 the default Ethernet interface, in case this is not 1804 determined through e.g. bootp. 1805 (Environment variable "ipaddr") 1806 1807- Server IP address: 1808 CONFIG_SERVERIP 1809 1810 Defines a default value for the IP address of a TFTP 1811 server to contact when using the "tftboot" command. 1812 (Environment variable "serverip") 1813 1814 CONFIG_KEEP_SERVERADDR 1815 1816 Keeps the server's MAC address, in the env 'serveraddr' 1817 for passing to bootargs (like Linux's netconsole option) 1818 1819- Gateway IP address: 1820 CONFIG_GATEWAYIP 1821 1822 Defines a default value for the IP address of the 1823 default router where packets to other networks are 1824 sent to. 1825 (Environment variable "gatewayip") 1826 1827- Subnet mask: 1828 CONFIG_NETMASK 1829 1830 Defines a default value for the subnet mask (or 1831 routing prefix) which is used to determine if an IP 1832 address belongs to the local subnet or needs to be 1833 forwarded through a router. 1834 (Environment variable "netmask") 1835 1836- Multicast TFTP Mode: 1837 CONFIG_MCAST_TFTP 1838 1839 Defines whether you want to support multicast TFTP as per 1840 rfc-2090; for example to work with atftp. Lets lots of targets 1841 tftp down the same boot image concurrently. Note: the Ethernet 1842 driver in use must provide a function: mcast() to join/leave a 1843 multicast group. 1844 1845- BOOTP Recovery Mode: 1846 CONFIG_BOOTP_RANDOM_DELAY 1847 1848 If you have many targets in a network that try to 1849 boot using BOOTP, you may want to avoid that all 1850 systems send out BOOTP requests at precisely the same 1851 moment (which would happen for instance at recovery 1852 from a power failure, when all systems will try to 1853 boot, thus flooding the BOOTP server. Defining 1854 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1855 inserted before sending out BOOTP requests. The 1856 following delays are inserted then: 1857 1858 1st BOOTP request: delay 0 ... 1 sec 1859 2nd BOOTP request: delay 0 ... 2 sec 1860 3rd BOOTP request: delay 0 ... 4 sec 1861 4th and following 1862 BOOTP requests: delay 0 ... 8 sec 1863 1864 CONFIG_BOOTP_ID_CACHE_SIZE 1865 1866 BOOTP packets are uniquely identified using a 32-bit ID. The 1867 server will copy the ID from client requests to responses and 1868 U-Boot will use this to determine if it is the destination of 1869 an incoming response. Some servers will check that addresses 1870 aren't in use before handing them out (usually using an ARP 1871 ping) and therefore take up to a few hundred milliseconds to 1872 respond. Network congestion may also influence the time it 1873 takes for a response to make it back to the client. If that 1874 time is too long, U-Boot will retransmit requests. In order 1875 to allow earlier responses to still be accepted after these 1876 retransmissions, U-Boot's BOOTP client keeps a small cache of 1877 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1878 cache. The default is to keep IDs for up to four outstanding 1879 requests. Increasing this will allow U-Boot to accept offers 1880 from a BOOTP client in networks with unusually high latency. 1881 1882- DHCP Advanced Options: 1883 You can fine tune the DHCP functionality by defining 1884 CONFIG_BOOTP_* symbols: 1885 1886 CONFIG_BOOTP_SUBNETMASK 1887 CONFIG_BOOTP_GATEWAY 1888 CONFIG_BOOTP_HOSTNAME 1889 CONFIG_BOOTP_NISDOMAIN 1890 CONFIG_BOOTP_BOOTPATH 1891 CONFIG_BOOTP_BOOTFILESIZE 1892 CONFIG_BOOTP_DNS 1893 CONFIG_BOOTP_DNS2 1894 CONFIG_BOOTP_SEND_HOSTNAME 1895 CONFIG_BOOTP_NTPSERVER 1896 CONFIG_BOOTP_TIMEOFFSET 1897 CONFIG_BOOTP_VENDOREX 1898 CONFIG_BOOTP_MAY_FAIL 1899 1900 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1901 environment variable, not the BOOTP server. 1902 1903 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1904 after the configured retry count, the call will fail 1905 instead of starting over. This can be used to fail over 1906 to Link-local IP address configuration if the DHCP server 1907 is not available. 1908 1909 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1910 serverip from a DHCP server, it is possible that more 1911 than one DNS serverip is offered to the client. 1912 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1913 serverip will be stored in the additional environment 1914 variable "dnsip2". The first DNS serverip is always 1915 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1916 is defined. 1917 1918 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1919 to do a dynamic update of a DNS server. To do this, they 1920 need the hostname of the DHCP requester. 1921 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1922 of the "hostname" environment variable is passed as 1923 option 12 to the DHCP server. 1924 1925 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1926 1927 A 32bit value in microseconds for a delay between 1928 receiving a "DHCP Offer" and sending the "DHCP Request". 1929 This fixes a problem with certain DHCP servers that don't 1930 respond 100% of the time to a "DHCP request". E.g. On an 1931 AT91RM9200 processor running at 180MHz, this delay needed 1932 to be *at least* 15,000 usec before a Windows Server 2003 1933 DHCP server would reply 100% of the time. I recommend at 1934 least 50,000 usec to be safe. The alternative is to hope 1935 that one of the retries will be successful but note that 1936 the DHCP timeout and retry process takes a longer than 1937 this delay. 1938 1939 - Link-local IP address negotiation: 1940 Negotiate with other link-local clients on the local network 1941 for an address that doesn't require explicit configuration. 1942 This is especially useful if a DHCP server cannot be guaranteed 1943 to exist in all environments that the device must operate. 1944 1945 See doc/README.link-local for more information. 1946 1947 - CDP Options: 1948 CONFIG_CDP_DEVICE_ID 1949 1950 The device id used in CDP trigger frames. 1951 1952 CONFIG_CDP_DEVICE_ID_PREFIX 1953 1954 A two character string which is prefixed to the MAC address 1955 of the device. 1956 1957 CONFIG_CDP_PORT_ID 1958 1959 A printf format string which contains the ascii name of 1960 the port. Normally is set to "eth%d" which sets 1961 eth0 for the first Ethernet, eth1 for the second etc. 1962 1963 CONFIG_CDP_CAPABILITIES 1964 1965 A 32bit integer which indicates the device capabilities; 1966 0x00000010 for a normal host which does not forwards. 1967 1968 CONFIG_CDP_VERSION 1969 1970 An ascii string containing the version of the software. 1971 1972 CONFIG_CDP_PLATFORM 1973 1974 An ascii string containing the name of the platform. 1975 1976 CONFIG_CDP_TRIGGER 1977 1978 A 32bit integer sent on the trigger. 1979 1980 CONFIG_CDP_POWER_CONSUMPTION 1981 1982 A 16bit integer containing the power consumption of the 1983 device in .1 of milliwatts. 1984 1985 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1986 1987 A byte containing the id of the VLAN. 1988 1989- Status LED: CONFIG_LED_STATUS 1990 1991 Several configurations allow to display the current 1992 status using a LED. For instance, the LED will blink 1993 fast while running U-Boot code, stop blinking as 1994 soon as a reply to a BOOTP request was received, and 1995 start blinking slow once the Linux kernel is running 1996 (supported by a status LED driver in the Linux 1997 kernel). Defining CONFIG_LED_STATUS enables this 1998 feature in U-Boot. 1999 2000 Additional options: 2001 2002 CONFIG_LED_STATUS_GPIO 2003 The status LED can be connected to a GPIO pin. 2004 In such cases, the gpio_led driver can be used as a 2005 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 2006 to include the gpio_led driver in the U-Boot binary. 2007 2008 CONFIG_GPIO_LED_INVERTED_TABLE 2009 Some GPIO connected LEDs may have inverted polarity in which 2010 case the GPIO high value corresponds to LED off state and 2011 GPIO low value corresponds to LED on state. 2012 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2013 with a list of GPIO LEDs that have inverted polarity. 2014 2015- CAN Support: CONFIG_CAN_DRIVER 2016 2017 Defining CONFIG_CAN_DRIVER enables CAN driver support 2018 on those systems that support this (optional) 2019 feature, like the TQM8xxL modules. 2020 2021- I2C Support: CONFIG_SYS_I2C 2022 2023 This enable the NEW i2c subsystem, and will allow you to use 2024 i2c commands at the u-boot command line (as long as you set 2025 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2026 based realtime clock chips or other i2c devices. See 2027 common/cmd_i2c.c for a description of the command line 2028 interface. 2029 2030 ported i2c driver to the new framework: 2031 - drivers/i2c/soft_i2c.c: 2032 - activate first bus with CONFIG_SYS_I2C_SOFT define 2033 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2034 for defining speed and slave address 2035 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2036 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2037 for defining speed and slave address 2038 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2039 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2040 for defining speed and slave address 2041 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2042 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2043 for defining speed and slave address 2044 2045 - drivers/i2c/fsl_i2c.c: 2046 - activate i2c driver with CONFIG_SYS_I2C_FSL 2047 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2048 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2049 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2050 bus. 2051 - If your board supports a second fsl i2c bus, define 2052 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2053 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2054 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2055 second bus. 2056 2057 - drivers/i2c/tegra_i2c.c: 2058 - activate this driver with CONFIG_SYS_I2C_TEGRA 2059 - This driver adds 4 i2c buses with a fix speed from 2060 100000 and the slave addr 0! 2061 2062 - drivers/i2c/ppc4xx_i2c.c 2063 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2064 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2065 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2066 2067 - drivers/i2c/i2c_mxc.c 2068 - activate this driver with CONFIG_SYS_I2C_MXC 2069 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2070 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2071 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2072 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2073 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2074 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2075 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2076 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2077 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2078 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2079 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2080 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2081 If those defines are not set, default value is 100000 2082 for speed, and 0 for slave. 2083 2084 - drivers/i2c/rcar_i2c.c: 2085 - activate this driver with CONFIG_SYS_I2C_RCAR 2086 - This driver adds 4 i2c buses 2087 2088 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2089 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2090 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2091 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2092 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2093 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2094 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2095 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2096 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2097 2098 - drivers/i2c/sh_i2c.c: 2099 - activate this driver with CONFIG_SYS_I2C_SH 2100 - This driver adds from 2 to 5 i2c buses 2101 2102 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2103 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2104 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2105 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2106 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2107 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2108 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2109 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2110 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2111 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2112 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2113 2114 - drivers/i2c/omap24xx_i2c.c 2115 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2116 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2117 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2118 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2119 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2120 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2121 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2122 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2123 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2124 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2125 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2126 2127 - drivers/i2c/zynq_i2c.c 2128 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2129 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2130 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2131 2132 - drivers/i2c/s3c24x0_i2c.c: 2133 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2134 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2135 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2136 with a fix speed from 100000 and the slave addr 0! 2137 2138 - drivers/i2c/ihs_i2c.c 2139 - activate this driver with CONFIG_SYS_I2C_IHS 2140 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2141 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2142 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2143 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2144 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2145 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2146 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2147 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2148 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2149 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2150 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2151 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2152 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2153 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2154 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2155 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2156 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2157 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2158 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2159 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2160 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2161 2162 additional defines: 2163 2164 CONFIG_SYS_NUM_I2C_BUSES 2165 Hold the number of i2c buses you want to use. 2166 2167 CONFIG_SYS_I2C_DIRECT_BUS 2168 define this, if you don't use i2c muxes on your hardware. 2169 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2170 omit this define. 2171 2172 CONFIG_SYS_I2C_MAX_HOPS 2173 define how many muxes are maximal consecutively connected 2174 on one i2c bus. If you not use i2c muxes, omit this 2175 define. 2176 2177 CONFIG_SYS_I2C_BUSES 2178 hold a list of buses you want to use, only used if 2179 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2180 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2181 CONFIG_SYS_NUM_I2C_BUSES = 9: 2182 2183 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2184 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2185 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2186 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2187 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2188 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2189 {1, {I2C_NULL_HOP}}, \ 2190 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2191 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2192 } 2193 2194 which defines 2195 bus 0 on adapter 0 without a mux 2196 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2197 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2198 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2199 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2200 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2201 bus 6 on adapter 1 without a mux 2202 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2203 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2204 2205 If you do not have i2c muxes on your board, omit this define. 2206 2207- Legacy I2C Support: 2208 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2209 then the following macros need to be defined (examples are 2210 from include/configs/lwmon.h): 2211 2212 I2C_INIT 2213 2214 (Optional). Any commands necessary to enable the I2C 2215 controller or configure ports. 2216 2217 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2218 2219 I2C_PORT 2220 2221 (Only for MPC8260 CPU). The I/O port to use (the code 2222 assumes both bits are on the same port). Valid values 2223 are 0..3 for ports A..D. 2224 2225 I2C_ACTIVE 2226 2227 The code necessary to make the I2C data line active 2228 (driven). If the data line is open collector, this 2229 define can be null. 2230 2231 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2232 2233 I2C_TRISTATE 2234 2235 The code necessary to make the I2C data line tri-stated 2236 (inactive). If the data line is open collector, this 2237 define can be null. 2238 2239 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2240 2241 I2C_READ 2242 2243 Code that returns true if the I2C data line is high, 2244 false if it is low. 2245 2246 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2247 2248 I2C_SDA(bit) 2249 2250 If <bit> is true, sets the I2C data line high. If it 2251 is false, it clears it (low). 2252 2253 eg: #define I2C_SDA(bit) \ 2254 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2255 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2256 2257 I2C_SCL(bit) 2258 2259 If <bit> is true, sets the I2C clock line high. If it 2260 is false, it clears it (low). 2261 2262 eg: #define I2C_SCL(bit) \ 2263 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2264 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2265 2266 I2C_DELAY 2267 2268 This delay is invoked four times per clock cycle so this 2269 controls the rate of data transfer. The data rate thus 2270 is 1 / (I2C_DELAY * 4). Often defined to be something 2271 like: 2272 2273 #define I2C_DELAY udelay(2) 2274 2275 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2276 2277 If your arch supports the generic GPIO framework (asm/gpio.h), 2278 then you may alternatively define the two GPIOs that are to be 2279 used as SCL / SDA. Any of the previous I2C_xxx macros will 2280 have GPIO-based defaults assigned to them as appropriate. 2281 2282 You should define these to the GPIO value as given directly to 2283 the generic GPIO functions. 2284 2285 CONFIG_SYS_I2C_INIT_BOARD 2286 2287 When a board is reset during an i2c bus transfer 2288 chips might think that the current transfer is still 2289 in progress. On some boards it is possible to access 2290 the i2c SCLK line directly, either by using the 2291 processor pin as a GPIO or by having a second pin 2292 connected to the bus. If this option is defined a 2293 custom i2c_init_board() routine in boards/xxx/board.c 2294 is run early in the boot sequence. 2295 2296 CONFIG_I2C_MULTI_BUS 2297 2298 This option allows the use of multiple I2C buses, each of which 2299 must have a controller. At any point in time, only one bus is 2300 active. To switch to a different bus, use the 'i2c dev' command. 2301 Note that bus numbering is zero-based. 2302 2303 CONFIG_SYS_I2C_NOPROBES 2304 2305 This option specifies a list of I2C devices that will be skipped 2306 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2307 is set, specify a list of bus-device pairs. Otherwise, specify 2308 a 1D array of device addresses 2309 2310 e.g. 2311 #undef CONFIG_I2C_MULTI_BUS 2312 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2313 2314 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2315 2316 #define CONFIG_I2C_MULTI_BUS 2317 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2318 2319 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2320 2321 CONFIG_SYS_SPD_BUS_NUM 2322 2323 If defined, then this indicates the I2C bus number for DDR SPD. 2324 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2325 2326 CONFIG_SYS_RTC_BUS_NUM 2327 2328 If defined, then this indicates the I2C bus number for the RTC. 2329 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2330 2331 CONFIG_SYS_DTT_BUS_NUM 2332 2333 If defined, then this indicates the I2C bus number for the DTT. 2334 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2335 2336 CONFIG_SYS_I2C_DTT_ADDR: 2337 2338 If defined, specifies the I2C address of the DTT device. 2339 If not defined, then U-Boot uses predefined value for 2340 specified DTT device. 2341 2342 CONFIG_SOFT_I2C_READ_REPEATED_START 2343 2344 defining this will force the i2c_read() function in 2345 the soft_i2c driver to perform an I2C repeated start 2346 between writing the address pointer and reading the 2347 data. If this define is omitted the default behaviour 2348 of doing a stop-start sequence will be used. Most I2C 2349 devices can use either method, but some require one or 2350 the other. 2351 2352- SPI Support: CONFIG_SPI 2353 2354 Enables SPI driver (so far only tested with 2355 SPI EEPROM, also an instance works with Crystal A/D and 2356 D/As on the SACSng board) 2357 2358 CONFIG_SH_SPI 2359 2360 Enables the driver for SPI controller on SuperH. Currently 2361 only SH7757 is supported. 2362 2363 CONFIG_SOFT_SPI 2364 2365 Enables a software (bit-bang) SPI driver rather than 2366 using hardware support. This is a general purpose 2367 driver that only requires three general I/O port pins 2368 (two outputs, one input) to function. If this is 2369 defined, the board configuration must define several 2370 SPI configuration items (port pins to use, etc). For 2371 an example, see include/configs/sacsng.h. 2372 2373 CONFIG_HARD_SPI 2374 2375 Enables a hardware SPI driver for general-purpose reads 2376 and writes. As with CONFIG_SOFT_SPI, the board configuration 2377 must define a list of chip-select function pointers. 2378 Currently supported on some MPC8xxx processors. For an 2379 example, see include/configs/mpc8349emds.h. 2380 2381 CONFIG_MXC_SPI 2382 2383 Enables the driver for the SPI controllers on i.MX and MXC 2384 SoCs. Currently i.MX31/35/51 are supported. 2385 2386 CONFIG_SYS_SPI_MXC_WAIT 2387 Timeout for waiting until spi transfer completed. 2388 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2389 2390- FPGA Support: CONFIG_FPGA 2391 2392 Enables FPGA subsystem. 2393 2394 CONFIG_FPGA_<vendor> 2395 2396 Enables support for specific chip vendors. 2397 (ALTERA, XILINX) 2398 2399 CONFIG_FPGA_<family> 2400 2401 Enables support for FPGA family. 2402 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2403 2404 CONFIG_FPGA_COUNT 2405 2406 Specify the number of FPGA devices to support. 2407 2408 CONFIG_CMD_FPGA_LOADMK 2409 2410 Enable support for fpga loadmk command 2411 2412 CONFIG_CMD_FPGA_LOADP 2413 2414 Enable support for fpga loadp command - load partial bitstream 2415 2416 CONFIG_CMD_FPGA_LOADBP 2417 2418 Enable support for fpga loadbp command - load partial bitstream 2419 (Xilinx only) 2420 2421 CONFIG_SYS_FPGA_PROG_FEEDBACK 2422 2423 Enable printing of hash marks during FPGA configuration. 2424 2425 CONFIG_SYS_FPGA_CHECK_BUSY 2426 2427 Enable checks on FPGA configuration interface busy 2428 status by the configuration function. This option 2429 will require a board or device specific function to 2430 be written. 2431 2432 CONFIG_FPGA_DELAY 2433 2434 If defined, a function that provides delays in the FPGA 2435 configuration driver. 2436 2437 CONFIG_SYS_FPGA_CHECK_CTRLC 2438 Allow Control-C to interrupt FPGA configuration 2439 2440 CONFIG_SYS_FPGA_CHECK_ERROR 2441 2442 Check for configuration errors during FPGA bitfile 2443 loading. For example, abort during Virtex II 2444 configuration if the INIT_B line goes low (which 2445 indicated a CRC error). 2446 2447 CONFIG_SYS_FPGA_WAIT_INIT 2448 2449 Maximum time to wait for the INIT_B line to de-assert 2450 after PROB_B has been de-asserted during a Virtex II 2451 FPGA configuration sequence. The default time is 500 2452 ms. 2453 2454 CONFIG_SYS_FPGA_WAIT_BUSY 2455 2456 Maximum time to wait for BUSY to de-assert during 2457 Virtex II FPGA configuration. The default is 5 ms. 2458 2459 CONFIG_SYS_FPGA_WAIT_CONFIG 2460 2461 Time to wait after FPGA configuration. The default is 2462 200 ms. 2463 2464- Configuration Management: 2465 CONFIG_BUILD_TARGET 2466 2467 Some SoCs need special image types (e.g. U-Boot binary 2468 with a special header) as build targets. By defining 2469 CONFIG_BUILD_TARGET in the SoC / board header, this 2470 special image will be automatically built upon calling 2471 make / buildman. 2472 2473 CONFIG_IDENT_STRING 2474 2475 If defined, this string will be added to the U-Boot 2476 version information (U_BOOT_VERSION) 2477 2478- Vendor Parameter Protection: 2479 2480 U-Boot considers the values of the environment 2481 variables "serial#" (Board Serial Number) and 2482 "ethaddr" (Ethernet Address) to be parameters that 2483 are set once by the board vendor / manufacturer, and 2484 protects these variables from casual modification by 2485 the user. Once set, these variables are read-only, 2486 and write or delete attempts are rejected. You can 2487 change this behaviour: 2488 2489 If CONFIG_ENV_OVERWRITE is #defined in your config 2490 file, the write protection for vendor parameters is 2491 completely disabled. Anybody can change or delete 2492 these parameters. 2493 2494 Alternatively, if you define _both_ an ethaddr in the 2495 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2496 Ethernet address is installed in the environment, 2497 which can be changed exactly ONCE by the user. [The 2498 serial# is unaffected by this, i. e. it remains 2499 read-only.] 2500 2501 The same can be accomplished in a more flexible way 2502 for any variable by configuring the type of access 2503 to allow for those variables in the ".flags" variable 2504 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2505 2506- Protected RAM: 2507 CONFIG_PRAM 2508 2509 Define this variable to enable the reservation of 2510 "protected RAM", i. e. RAM which is not overwritten 2511 by U-Boot. Define CONFIG_PRAM to hold the number of 2512 kB you want to reserve for pRAM. You can overwrite 2513 this default value by defining an environment 2514 variable "pram" to the number of kB you want to 2515 reserve. Note that the board info structure will 2516 still show the full amount of RAM. If pRAM is 2517 reserved, a new environment variable "mem" will 2518 automatically be defined to hold the amount of 2519 remaining RAM in a form that can be passed as boot 2520 argument to Linux, for instance like that: 2521 2522 setenv bootargs ... mem=\${mem} 2523 saveenv 2524 2525 This way you can tell Linux not to use this memory, 2526 either, which results in a memory region that will 2527 not be affected by reboots. 2528 2529 *WARNING* If your board configuration uses automatic 2530 detection of the RAM size, you must make sure that 2531 this memory test is non-destructive. So far, the 2532 following board configurations are known to be 2533 "pRAM-clean": 2534 2535 IVMS8, IVML24, SPD8xx, TQM8xxL, 2536 HERMES, IP860, RPXlite, LWMON, 2537 FLAGADM, TQM8260 2538 2539- Access to physical memory region (> 4GB) 2540 Some basic support is provided for operations on memory not 2541 normally accessible to U-Boot - e.g. some architectures 2542 support access to more than 4GB of memory on 32-bit 2543 machines using physical address extension or similar. 2544 Define CONFIG_PHYSMEM to access this basic support, which 2545 currently only supports clearing the memory. 2546 2547- Error Recovery: 2548 CONFIG_PANIC_HANG 2549 2550 Define this variable to stop the system in case of a 2551 fatal error, so that you have to reset it manually. 2552 This is probably NOT a good idea for an embedded 2553 system where you want the system to reboot 2554 automatically as fast as possible, but it may be 2555 useful during development since you can try to debug 2556 the conditions that lead to the situation. 2557 2558 CONFIG_NET_RETRY_COUNT 2559 2560 This variable defines the number of retries for 2561 network operations like ARP, RARP, TFTP, or BOOTP 2562 before giving up the operation. If not defined, a 2563 default value of 5 is used. 2564 2565 CONFIG_ARP_TIMEOUT 2566 2567 Timeout waiting for an ARP reply in milliseconds. 2568 2569 CONFIG_NFS_TIMEOUT 2570 2571 Timeout in milliseconds used in NFS protocol. 2572 If you encounter "ERROR: Cannot umount" in nfs command, 2573 try longer timeout such as 2574 #define CONFIG_NFS_TIMEOUT 10000UL 2575 2576- Command Interpreter: 2577 CONFIG_AUTO_COMPLETE 2578 2579 Enable auto completion of commands using TAB. 2580 2581 CONFIG_SYS_PROMPT_HUSH_PS2 2582 2583 This defines the secondary prompt string, which is 2584 printed when the command interpreter needs more input 2585 to complete a command. Usually "> ". 2586 2587 Note: 2588 2589 In the current implementation, the local variables 2590 space and global environment variables space are 2591 separated. Local variables are those you define by 2592 simply typing `name=value'. To access a local 2593 variable later on, you have write `$name' or 2594 `${name}'; to execute the contents of a variable 2595 directly type `$name' at the command prompt. 2596 2597 Global environment variables are those you use 2598 setenv/printenv to work with. To run a command stored 2599 in such a variable, you need to use the run command, 2600 and you must not use the '$' sign to access them. 2601 2602 To store commands and special characters in a 2603 variable, please use double quotation marks 2604 surrounding the whole text of the variable, instead 2605 of the backslashes before semicolons and special 2606 symbols. 2607 2608- Command Line Editing and History: 2609 CONFIG_CMDLINE_EDITING 2610 2611 Enable editing and History functions for interactive 2612 command line input operations 2613 2614- Command Line PS1/PS2 support: 2615 CONFIG_CMDLINE_PS_SUPPORT 2616 2617 Enable support for changing the command prompt string 2618 at run-time. Only static string is supported so far. 2619 The string is obtained from environment variables PS1 2620 and PS2. 2621 2622- Default Environment: 2623 CONFIG_EXTRA_ENV_SETTINGS 2624 2625 Define this to contain any number of null terminated 2626 strings (variable = value pairs) that will be part of 2627 the default environment compiled into the boot image. 2628 2629 For example, place something like this in your 2630 board's config file: 2631 2632 #define CONFIG_EXTRA_ENV_SETTINGS \ 2633 "myvar1=value1\0" \ 2634 "myvar2=value2\0" 2635 2636 Warning: This method is based on knowledge about the 2637 internal format how the environment is stored by the 2638 U-Boot code. This is NOT an official, exported 2639 interface! Although it is unlikely that this format 2640 will change soon, there is no guarantee either. 2641 You better know what you are doing here. 2642 2643 Note: overly (ab)use of the default environment is 2644 discouraged. Make sure to check other ways to preset 2645 the environment like the "source" command or the 2646 boot command first. 2647 2648 CONFIG_ENV_VARS_UBOOT_CONFIG 2649 2650 Define this in order to add variables describing the 2651 U-Boot build configuration to the default environment. 2652 These will be named arch, cpu, board, vendor, and soc. 2653 2654 Enabling this option will cause the following to be defined: 2655 2656 - CONFIG_SYS_ARCH 2657 - CONFIG_SYS_CPU 2658 - CONFIG_SYS_BOARD 2659 - CONFIG_SYS_VENDOR 2660 - CONFIG_SYS_SOC 2661 2662 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2663 2664 Define this in order to add variables describing certain 2665 run-time determined information about the hardware to the 2666 environment. These will be named board_name, board_rev. 2667 2668 CONFIG_DELAY_ENVIRONMENT 2669 2670 Normally the environment is loaded when the board is 2671 initialised so that it is available to U-Boot. This inhibits 2672 that so that the environment is not available until 2673 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2674 this is instead controlled by the value of 2675 /config/load-environment. 2676 2677- DataFlash Support: 2678 CONFIG_HAS_DATAFLASH 2679 2680 Defining this option enables DataFlash features and 2681 allows to read/write in Dataflash via the standard 2682 commands cp, md... 2683 2684- Serial Flash support 2685 CONFIG_CMD_SF 2686 2687 Defining this option enables SPI flash commands 2688 'sf probe/read/write/erase/update'. 2689 2690 Usage requires an initial 'probe' to define the serial 2691 flash parameters, followed by read/write/erase/update 2692 commands. 2693 2694 The following defaults may be provided by the platform 2695 to handle the common case when only a single serial 2696 flash is present on the system. 2697 2698 CONFIG_SF_DEFAULT_BUS Bus identifier 2699 CONFIG_SF_DEFAULT_CS Chip-select 2700 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2701 CONFIG_SF_DEFAULT_SPEED in Hz 2702 2703 CONFIG_CMD_SF_TEST 2704 2705 Define this option to include a destructive SPI flash 2706 test ('sf test'). 2707 2708 CONFIG_SF_DUAL_FLASH Dual flash memories 2709 2710 Define this option to use dual flash support where two flash 2711 memories can be connected with a given cs line. 2712 Currently Xilinx Zynq qspi supports these type of connections. 2713 2714- SystemACE Support: 2715 CONFIG_SYSTEMACE 2716 2717 Adding this option adds support for Xilinx SystemACE 2718 chips attached via some sort of local bus. The address 2719 of the chip must also be defined in the 2720 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2721 2722 #define CONFIG_SYSTEMACE 2723 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2724 2725 When SystemACE support is added, the "ace" device type 2726 becomes available to the fat commands, i.e. fatls. 2727 2728- TFTP Fixed UDP Port: 2729 CONFIG_TFTP_PORT 2730 2731 If this is defined, the environment variable tftpsrcp 2732 is used to supply the TFTP UDP source port value. 2733 If tftpsrcp isn't defined, the normal pseudo-random port 2734 number generator is used. 2735 2736 Also, the environment variable tftpdstp is used to supply 2737 the TFTP UDP destination port value. If tftpdstp isn't 2738 defined, the normal port 69 is used. 2739 2740 The purpose for tftpsrcp is to allow a TFTP server to 2741 blindly start the TFTP transfer using the pre-configured 2742 target IP address and UDP port. This has the effect of 2743 "punching through" the (Windows XP) firewall, allowing 2744 the remainder of the TFTP transfer to proceed normally. 2745 A better solution is to properly configure the firewall, 2746 but sometimes that is not allowed. 2747 2748- Hashing support: 2749 CONFIG_CMD_HASH 2750 2751 This enables a generic 'hash' command which can produce 2752 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2753 2754 CONFIG_HASH_VERIFY 2755 2756 Enable the hash verify command (hash -v). This adds to code 2757 size a little. 2758 2759 CONFIG_SHA1 - This option enables support of hashing using SHA1 2760 algorithm. The hash is calculated in software. 2761 CONFIG_SHA256 - This option enables support of hashing using 2762 SHA256 algorithm. The hash is calculated in software. 2763 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 2764 for SHA1/SHA256 hashing. 2765 This affects the 'hash' command and also the 2766 hash_lookup_algo() function. 2767 CONFIG_SHA_PROG_HW_ACCEL - This option enables 2768 hardware-acceleration for SHA1/SHA256 progressive hashing. 2769 Data can be streamed in a block at a time and the hashing 2770 is performed in hardware. 2771 2772 Note: There is also a sha1sum command, which should perhaps 2773 be deprecated in favour of 'hash sha1'. 2774 2775- Freescale i.MX specific commands: 2776 CONFIG_CMD_HDMIDETECT 2777 This enables 'hdmidet' command which returns true if an 2778 HDMI monitor is detected. This command is i.MX 6 specific. 2779 2780- bootcount support: 2781 CONFIG_BOOTCOUNT_LIMIT 2782 2783 This enables the bootcounter support, see: 2784 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2785 2786 CONFIG_AT91SAM9XE 2787 enable special bootcounter support on at91sam9xe based boards. 2788 CONFIG_SOC_DA8XX 2789 enable special bootcounter support on da850 based boards. 2790 CONFIG_BOOTCOUNT_RAM 2791 enable support for the bootcounter in RAM 2792 CONFIG_BOOTCOUNT_I2C 2793 enable support for the bootcounter on an i2c (like RTC) device. 2794 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2795 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2796 the bootcounter. 2797 CONFIG_BOOTCOUNT_ALEN = address len 2798 2799- Show boot progress: 2800 CONFIG_SHOW_BOOT_PROGRESS 2801 2802 Defining this option allows to add some board- 2803 specific code (calling a user-provided function 2804 "show_boot_progress(int)") that enables you to show 2805 the system's boot progress on some display (for 2806 example, some LED's) on your board. At the moment, 2807 the following checkpoints are implemented: 2808 2809 2810Legacy uImage format: 2811 2812 Arg Where When 2813 1 common/cmd_bootm.c before attempting to boot an image 2814 -1 common/cmd_bootm.c Image header has bad magic number 2815 2 common/cmd_bootm.c Image header has correct magic number 2816 -2 common/cmd_bootm.c Image header has bad checksum 2817 3 common/cmd_bootm.c Image header has correct checksum 2818 -3 common/cmd_bootm.c Image data has bad checksum 2819 4 common/cmd_bootm.c Image data has correct checksum 2820 -4 common/cmd_bootm.c Image is for unsupported architecture 2821 5 common/cmd_bootm.c Architecture check OK 2822 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2823 6 common/cmd_bootm.c Image Type check OK 2824 -6 common/cmd_bootm.c gunzip uncompression error 2825 -7 common/cmd_bootm.c Unimplemented compression type 2826 7 common/cmd_bootm.c Uncompression OK 2827 8 common/cmd_bootm.c No uncompress/copy overwrite error 2828 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2829 2830 9 common/image.c Start initial ramdisk verification 2831 -10 common/image.c Ramdisk header has bad magic number 2832 -11 common/image.c Ramdisk header has bad checksum 2833 10 common/image.c Ramdisk header is OK 2834 -12 common/image.c Ramdisk data has bad checksum 2835 11 common/image.c Ramdisk data has correct checksum 2836 12 common/image.c Ramdisk verification complete, start loading 2837 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2838 13 common/image.c Start multifile image verification 2839 14 common/image.c No initial ramdisk, no multifile, continue. 2840 2841 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2842 2843 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2844 -31 post/post.c POST test failed, detected by post_output_backlog() 2845 -32 post/post.c POST test failed, detected by post_run_single() 2846 2847 34 common/cmd_doc.c before loading a Image from a DOC device 2848 -35 common/cmd_doc.c Bad usage of "doc" command 2849 35 common/cmd_doc.c correct usage of "doc" command 2850 -36 common/cmd_doc.c No boot device 2851 36 common/cmd_doc.c correct boot device 2852 -37 common/cmd_doc.c Unknown Chip ID on boot device 2853 37 common/cmd_doc.c correct chip ID found, device available 2854 -38 common/cmd_doc.c Read Error on boot device 2855 38 common/cmd_doc.c reading Image header from DOC device OK 2856 -39 common/cmd_doc.c Image header has bad magic number 2857 39 common/cmd_doc.c Image header has correct magic number 2858 -40 common/cmd_doc.c Error reading Image from DOC device 2859 40 common/cmd_doc.c Image header has correct magic number 2860 41 common/cmd_ide.c before loading a Image from a IDE device 2861 -42 common/cmd_ide.c Bad usage of "ide" command 2862 42 common/cmd_ide.c correct usage of "ide" command 2863 -43 common/cmd_ide.c No boot device 2864 43 common/cmd_ide.c boot device found 2865 -44 common/cmd_ide.c Device not available 2866 44 common/cmd_ide.c Device available 2867 -45 common/cmd_ide.c wrong partition selected 2868 45 common/cmd_ide.c partition selected 2869 -46 common/cmd_ide.c Unknown partition table 2870 46 common/cmd_ide.c valid partition table found 2871 -47 common/cmd_ide.c Invalid partition type 2872 47 common/cmd_ide.c correct partition type 2873 -48 common/cmd_ide.c Error reading Image Header on boot device 2874 48 common/cmd_ide.c reading Image Header from IDE device OK 2875 -49 common/cmd_ide.c Image header has bad magic number 2876 49 common/cmd_ide.c Image header has correct magic number 2877 -50 common/cmd_ide.c Image header has bad checksum 2878 50 common/cmd_ide.c Image header has correct checksum 2879 -51 common/cmd_ide.c Error reading Image from IDE device 2880 51 common/cmd_ide.c reading Image from IDE device OK 2881 52 common/cmd_nand.c before loading a Image from a NAND device 2882 -53 common/cmd_nand.c Bad usage of "nand" command 2883 53 common/cmd_nand.c correct usage of "nand" command 2884 -54 common/cmd_nand.c No boot device 2885 54 common/cmd_nand.c boot device found 2886 -55 common/cmd_nand.c Unknown Chip ID on boot device 2887 55 common/cmd_nand.c correct chip ID found, device available 2888 -56 common/cmd_nand.c Error reading Image Header on boot device 2889 56 common/cmd_nand.c reading Image Header from NAND device OK 2890 -57 common/cmd_nand.c Image header has bad magic number 2891 57 common/cmd_nand.c Image header has correct magic number 2892 -58 common/cmd_nand.c Error reading Image from NAND device 2893 58 common/cmd_nand.c reading Image from NAND device OK 2894 2895 -60 common/env_common.c Environment has a bad CRC, using default 2896 2897 64 net/eth.c starting with Ethernet configuration. 2898 -64 net/eth.c no Ethernet found. 2899 65 net/eth.c Ethernet found. 2900 2901 -80 common/cmd_net.c usage wrong 2902 80 common/cmd_net.c before calling net_loop() 2903 -81 common/cmd_net.c some error in net_loop() occurred 2904 81 common/cmd_net.c net_loop() back without error 2905 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2906 82 common/cmd_net.c trying automatic boot 2907 83 common/cmd_net.c running "source" command 2908 -83 common/cmd_net.c some error in automatic boot or "source" command 2909 84 common/cmd_net.c end without errors 2910 2911FIT uImage format: 2912 2913 Arg Where When 2914 100 common/cmd_bootm.c Kernel FIT Image has correct format 2915 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2916 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2917 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2918 102 common/cmd_bootm.c Kernel unit name specified 2919 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2920 103 common/cmd_bootm.c Found configuration node 2921 104 common/cmd_bootm.c Got kernel subimage node offset 2922 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2923 105 common/cmd_bootm.c Kernel subimage hash verification OK 2924 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2925 106 common/cmd_bootm.c Architecture check OK 2926 -106 common/cmd_bootm.c Kernel subimage has wrong type 2927 107 common/cmd_bootm.c Kernel subimage type OK 2928 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2929 108 common/cmd_bootm.c Got kernel subimage data/size 2930 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2931 -109 common/cmd_bootm.c Can't get kernel subimage type 2932 -110 common/cmd_bootm.c Can't get kernel subimage comp 2933 -111 common/cmd_bootm.c Can't get kernel subimage os 2934 -112 common/cmd_bootm.c Can't get kernel subimage load address 2935 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2936 2937 120 common/image.c Start initial ramdisk verification 2938 -120 common/image.c Ramdisk FIT image has incorrect format 2939 121 common/image.c Ramdisk FIT image has correct format 2940 122 common/image.c No ramdisk subimage unit name, using configuration 2941 -122 common/image.c Can't get configuration for ramdisk subimage 2942 123 common/image.c Ramdisk unit name specified 2943 -124 common/image.c Can't get ramdisk subimage node offset 2944 125 common/image.c Got ramdisk subimage node offset 2945 -125 common/image.c Ramdisk subimage hash verification failed 2946 126 common/image.c Ramdisk subimage hash verification OK 2947 -126 common/image.c Ramdisk subimage for unsupported architecture 2948 127 common/image.c Architecture check OK 2949 -127 common/image.c Can't get ramdisk subimage data/size 2950 128 common/image.c Got ramdisk subimage data/size 2951 129 common/image.c Can't get ramdisk load address 2952 -129 common/image.c Got ramdisk load address 2953 2954 -130 common/cmd_doc.c Incorrect FIT image format 2955 131 common/cmd_doc.c FIT image format OK 2956 2957 -140 common/cmd_ide.c Incorrect FIT image format 2958 141 common/cmd_ide.c FIT image format OK 2959 2960 -150 common/cmd_nand.c Incorrect FIT image format 2961 151 common/cmd_nand.c FIT image format OK 2962 2963- legacy image format: 2964 CONFIG_IMAGE_FORMAT_LEGACY 2965 enables the legacy image format support in U-Boot. 2966 2967 Default: 2968 enabled if CONFIG_FIT_SIGNATURE is not defined. 2969 2970 CONFIG_DISABLE_IMAGE_LEGACY 2971 disable the legacy image format 2972 2973 This define is introduced, as the legacy image format is 2974 enabled per default for backward compatibility. 2975 2976- FIT image support: 2977 CONFIG_FIT_DISABLE_SHA256 2978 Supporting SHA256 hashes has quite an impact on binary size. 2979 For constrained systems sha256 hash support can be disabled 2980 with this option. 2981 2982 TODO(sjg@chromium.org): Adjust this option to be positive, 2983 and move it to Kconfig 2984 2985- Standalone program support: 2986 CONFIG_STANDALONE_LOAD_ADDR 2987 2988 This option defines a board specific value for the 2989 address where standalone program gets loaded, thus 2990 overwriting the architecture dependent default 2991 settings. 2992 2993- Frame Buffer Address: 2994 CONFIG_FB_ADDR 2995 2996 Define CONFIG_FB_ADDR if you want to use specific 2997 address for frame buffer. This is typically the case 2998 when using a graphics controller has separate video 2999 memory. U-Boot will then place the frame buffer at 3000 the given address instead of dynamically reserving it 3001 in system RAM by calling lcd_setmem(), which grabs 3002 the memory for the frame buffer depending on the 3003 configured panel size. 3004 3005 Please see board_init_f function. 3006 3007- Automatic software updates via TFTP server 3008 CONFIG_UPDATE_TFTP 3009 CONFIG_UPDATE_TFTP_CNT_MAX 3010 CONFIG_UPDATE_TFTP_MSEC_MAX 3011 3012 These options enable and control the auto-update feature; 3013 for a more detailed description refer to doc/README.update. 3014 3015- MTD Support (mtdparts command, UBI support) 3016 CONFIG_MTD_DEVICE 3017 3018 Adds the MTD device infrastructure from the Linux kernel. 3019 Needed for mtdparts command support. 3020 3021 CONFIG_MTD_PARTITIONS 3022 3023 Adds the MTD partitioning infrastructure from the Linux 3024 kernel. Needed for UBI support. 3025 3026- UBI support 3027 CONFIG_CMD_UBI 3028 3029 Adds commands for interacting with MTD partitions formatted 3030 with the UBI flash translation layer 3031 3032 Requires also defining CONFIG_RBTREE 3033 3034 CONFIG_UBI_SILENCE_MSG 3035 3036 Make the verbose messages from UBI stop printing. This leaves 3037 warnings and errors enabled. 3038 3039 3040 CONFIG_MTD_UBI_WL_THRESHOLD 3041 This parameter defines the maximum difference between the highest 3042 erase counter value and the lowest erase counter value of eraseblocks 3043 of UBI devices. When this threshold is exceeded, UBI starts performing 3044 wear leveling by means of moving data from eraseblock with low erase 3045 counter to eraseblocks with high erase counter. 3046 3047 The default value should be OK for SLC NAND flashes, NOR flashes and 3048 other flashes which have eraseblock life-cycle 100000 or more. 3049 However, in case of MLC NAND flashes which typically have eraseblock 3050 life-cycle less than 10000, the threshold should be lessened (e.g., 3051 to 128 or 256, although it does not have to be power of 2). 3052 3053 default: 4096 3054 3055 CONFIG_MTD_UBI_BEB_LIMIT 3056 This option specifies the maximum bad physical eraseblocks UBI 3057 expects on the MTD device (per 1024 eraseblocks). If the 3058 underlying flash does not admit of bad eraseblocks (e.g. NOR 3059 flash), this value is ignored. 3060 3061 NAND datasheets often specify the minimum and maximum NVM 3062 (Number of Valid Blocks) for the flashes' endurance lifetime. 3063 The maximum expected bad eraseblocks per 1024 eraseblocks 3064 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3065 which gives 20 for most NANDs (MaxNVB is basically the total 3066 count of eraseblocks on the chip). 3067 3068 To put it differently, if this value is 20, UBI will try to 3069 reserve about 1.9% of physical eraseblocks for bad blocks 3070 handling. And that will be 1.9% of eraseblocks on the entire 3071 NAND chip, not just the MTD partition UBI attaches. This means 3072 that if you have, say, a NAND flash chip admits maximum 40 bad 3073 eraseblocks, and it is split on two MTD partitions of the same 3074 size, UBI will reserve 40 eraseblocks when attaching a 3075 partition. 3076 3077 default: 20 3078 3079 CONFIG_MTD_UBI_FASTMAP 3080 Fastmap is a mechanism which allows attaching an UBI device 3081 in nearly constant time. Instead of scanning the whole MTD device it 3082 only has to locate a checkpoint (called fastmap) on the device. 3083 The on-flash fastmap contains all information needed to attach 3084 the device. Using fastmap makes only sense on large devices where 3085 attaching by scanning takes long. UBI will not automatically install 3086 a fastmap on old images, but you can set the UBI parameter 3087 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3088 that fastmap-enabled images are still usable with UBI implementations 3089 without fastmap support. On typical flash devices the whole fastmap 3090 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3091 3092 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3093 Set this parameter to enable fastmap automatically on images 3094 without a fastmap. 3095 default: 0 3096 3097 CONFIG_MTD_UBI_FM_DEBUG 3098 Enable UBI fastmap debug 3099 default: 0 3100 3101- UBIFS support 3102 CONFIG_CMD_UBIFS 3103 3104 Adds commands for interacting with UBI volumes formatted as 3105 UBIFS. UBIFS is read-only in u-boot. 3106 3107 Requires UBI support as well as CONFIG_LZO 3108 3109 CONFIG_UBIFS_SILENCE_MSG 3110 3111 Make the verbose messages from UBIFS stop printing. This leaves 3112 warnings and errors enabled. 3113 3114- SPL framework 3115 CONFIG_SPL 3116 Enable building of SPL globally. 3117 3118 CONFIG_SPL_LDSCRIPT 3119 LDSCRIPT for linking the SPL binary. 3120 3121 CONFIG_SPL_MAX_FOOTPRINT 3122 Maximum size in memory allocated to the SPL, BSS included. 3123 When defined, the linker checks that the actual memory 3124 used by SPL from _start to __bss_end does not exceed it. 3125 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3126 must not be both defined at the same time. 3127 3128 CONFIG_SPL_MAX_SIZE 3129 Maximum size of the SPL image (text, data, rodata, and 3130 linker lists sections), BSS excluded. 3131 When defined, the linker checks that the actual size does 3132 not exceed it. 3133 3134 CONFIG_SPL_TEXT_BASE 3135 TEXT_BASE for linking the SPL binary. 3136 3137 CONFIG_SPL_RELOC_TEXT_BASE 3138 Address to relocate to. If unspecified, this is equal to 3139 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3140 3141 CONFIG_SPL_BSS_START_ADDR 3142 Link address for the BSS within the SPL binary. 3143 3144 CONFIG_SPL_BSS_MAX_SIZE 3145 Maximum size in memory allocated to the SPL BSS. 3146 When defined, the linker checks that the actual memory used 3147 by SPL from __bss_start to __bss_end does not exceed it. 3148 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3149 must not be both defined at the same time. 3150 3151 CONFIG_SPL_STACK 3152 Adress of the start of the stack SPL will use 3153 3154 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3155 When defined, SPL will panic() if the image it has 3156 loaded does not have a signature. 3157 Defining this is useful when code which loads images 3158 in SPL cannot guarantee that absolutely all read errors 3159 will be caught. 3160 An example is the LPC32XX MLC NAND driver, which will 3161 consider that a completely unreadable NAND block is bad, 3162 and thus should be skipped silently. 3163 3164 CONFIG_SPL_RELOC_STACK 3165 Adress of the start of the stack SPL will use after 3166 relocation. If unspecified, this is equal to 3167 CONFIG_SPL_STACK. 3168 3169 CONFIG_SYS_SPL_MALLOC_START 3170 Starting address of the malloc pool used in SPL. 3171 When this option is set the full malloc is used in SPL and 3172 it is set up by spl_init() and before that, the simple malloc() 3173 can be used if CONFIG_SYS_MALLOC_F is defined. 3174 3175 CONFIG_SYS_SPL_MALLOC_SIZE 3176 The size of the malloc pool used in SPL. 3177 3178 CONFIG_SPL_FRAMEWORK 3179 Enable the SPL framework under common/. This framework 3180 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3181 NAND loading of the Linux Kernel. 3182 3183 CONFIG_SPL_OS_BOOT 3184 Enable booting directly to an OS from SPL. 3185 See also: doc/README.falcon 3186 3187 CONFIG_SPL_DISPLAY_PRINT 3188 For ARM, enable an optional function to print more information 3189 about the running system. 3190 3191 CONFIG_SPL_INIT_MINIMAL 3192 Arch init code should be built for a very small image 3193 3194 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3195 Partition on the MMC to load U-Boot from when the MMC is being 3196 used in raw mode 3197 3198 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3199 Sector to load kernel uImage from when MMC is being 3200 used in raw mode (for Falcon mode) 3201 3202 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3203 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3204 Sector and number of sectors to load kernel argument 3205 parameters from when MMC is being used in raw mode 3206 (for falcon mode) 3207 3208 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3209 Partition on the MMC to load U-Boot from when the MMC is being 3210 used in fs mode 3211 3212 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3213 Filename to read to load U-Boot when reading from filesystem 3214 3215 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3216 Filename to read to load kernel uImage when reading 3217 from filesystem (for Falcon mode) 3218 3219 CONFIG_SPL_FS_LOAD_ARGS_NAME 3220 Filename to read to load kernel argument parameters 3221 when reading from filesystem (for Falcon mode) 3222 3223 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3224 Set this for NAND SPL on PPC mpc83xx targets, so that 3225 start.S waits for the rest of the SPL to load before 3226 continuing (the hardware starts execution after just 3227 loading the first page rather than the full 4K). 3228 3229 CONFIG_SPL_SKIP_RELOCATE 3230 Avoid SPL relocation 3231 3232 CONFIG_SPL_NAND_BASE 3233 Include nand_base.c in the SPL. Requires 3234 CONFIG_SPL_NAND_DRIVERS. 3235 3236 CONFIG_SPL_NAND_DRIVERS 3237 SPL uses normal NAND drivers, not minimal drivers. 3238 3239 CONFIG_SPL_NAND_ECC 3240 Include standard software ECC in the SPL 3241 3242 CONFIG_SPL_NAND_SIMPLE 3243 Support for NAND boot using simple NAND drivers that 3244 expose the cmd_ctrl() interface. 3245 3246 CONFIG_SPL_UBI 3247 Support for a lightweight UBI (fastmap) scanner and 3248 loader 3249 3250 CONFIG_SPL_NAND_RAW_ONLY 3251 Support to boot only raw u-boot.bin images. Use this only 3252 if you need to save space. 3253 3254 CONFIG_SPL_COMMON_INIT_DDR 3255 Set for common ddr init with serial presence detect in 3256 SPL binary. 3257 3258 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3259 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3260 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3261 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3262 CONFIG_SYS_NAND_ECCBYTES 3263 Defines the size and behavior of the NAND that SPL uses 3264 to read U-Boot 3265 3266 CONFIG_SPL_NAND_BOOT 3267 Add support NAND boot 3268 3269 CONFIG_SYS_NAND_U_BOOT_OFFS 3270 Location in NAND to read U-Boot from 3271 3272 CONFIG_SYS_NAND_U_BOOT_DST 3273 Location in memory to load U-Boot to 3274 3275 CONFIG_SYS_NAND_U_BOOT_SIZE 3276 Size of image to load 3277 3278 CONFIG_SYS_NAND_U_BOOT_START 3279 Entry point in loaded image to jump to 3280 3281 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3282 Define this if you need to first read the OOB and then the 3283 data. This is used, for example, on davinci platforms. 3284 3285 CONFIG_SPL_OMAP3_ID_NAND 3286 Support for an OMAP3-specific set of functions to return the 3287 ID and MFR of the first attached NAND chip, if present. 3288 3289 CONFIG_SPL_RAM_DEVICE 3290 Support for running image already present in ram, in SPL binary 3291 3292 CONFIG_SPL_PAD_TO 3293 Image offset to which the SPL should be padded before appending 3294 the SPL payload. By default, this is defined as 3295 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3296 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3297 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3298 3299 CONFIG_SPL_TARGET 3300 Final target image containing SPL and payload. Some SPLs 3301 use an arch-specific makefile fragment instead, for 3302 example if more than one image needs to be produced. 3303 3304 CONFIG_FIT_SPL_PRINT 3305 Printing information about a FIT image adds quite a bit of 3306 code to SPL. So this is normally disabled in SPL. Use this 3307 option to re-enable it. This will affect the output of the 3308 bootm command when booting a FIT image. 3309 3310- TPL framework 3311 CONFIG_TPL 3312 Enable building of TPL globally. 3313 3314 CONFIG_TPL_PAD_TO 3315 Image offset to which the TPL should be padded before appending 3316 the TPL payload. By default, this is defined as 3317 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3318 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3319 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3320 3321- Interrupt support (PPC): 3322 3323 There are common interrupt_init() and timer_interrupt() 3324 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3325 for CPU specific initialization. interrupt_init_cpu() 3326 should set decrementer_count to appropriate value. If 3327 CPU resets decrementer automatically after interrupt 3328 (ppc4xx) it should set decrementer_count to zero. 3329 timer_interrupt() calls timer_interrupt_cpu() for CPU 3330 specific handling. If board has watchdog / status_led 3331 / other_activity_monitor it works automatically from 3332 general timer_interrupt(). 3333 3334 3335Board initialization settings: 3336------------------------------ 3337 3338During Initialization u-boot calls a number of board specific functions 3339to allow the preparation of board specific prerequisites, e.g. pin setup 3340before drivers are initialized. To enable these callbacks the 3341following configuration macros have to be defined. Currently this is 3342architecture specific, so please check arch/your_architecture/lib/board.c 3343typically in board_init_f() and board_init_r(). 3344 3345- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3346- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3347- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3348- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3349 3350Configuration Settings: 3351----------------------- 3352 3353- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3354 Optionally it can be defined to support 64-bit memory commands. 3355 3356- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3357 undefine this when you're short of memory. 3358 3359- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3360 width of the commands listed in the 'help' command output. 3361 3362- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3363 prompt for user input. 3364 3365- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3366 3367- CONFIG_SYS_PBSIZE: Buffer size for Console output 3368 3369- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3370 3371- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3372 the application (usually a Linux kernel) when it is 3373 booted 3374 3375- CONFIG_SYS_BAUDRATE_TABLE: 3376 List of legal baudrate settings for this board. 3377 3378- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3379 Begin and End addresses of the area used by the 3380 simple memory test. 3381 3382- CONFIG_SYS_ALT_MEMTEST: 3383 Enable an alternate, more extensive memory test. 3384 3385- CONFIG_SYS_MEMTEST_SCRATCH: 3386 Scratch address used by the alternate memory test 3387 You only need to set this if address zero isn't writeable 3388 3389- CONFIG_SYS_MEM_RESERVE_SECURE 3390 Only implemented for ARMv8 for now. 3391 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3392 is substracted from total RAM and won't be reported to OS. 3393 This memory can be used as secure memory. A variable 3394 gd->arch.secure_ram is used to track the location. In systems 3395 the RAM base is not zero, or RAM is divided into banks, 3396 this variable needs to be recalcuated to get the address. 3397 3398- CONFIG_SYS_MEM_TOP_HIDE: 3399 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3400 this specified memory area will get subtracted from the top 3401 (end) of RAM and won't get "touched" at all by U-Boot. By 3402 fixing up gd->ram_size the Linux kernel should gets passed 3403 the now "corrected" memory size and won't touch it either. 3404 This should work for arch/ppc and arch/powerpc. Only Linux 3405 board ports in arch/powerpc with bootwrapper support that 3406 recalculate the memory size from the SDRAM controller setup 3407 will have to get fixed in Linux additionally. 3408 3409 This option can be used as a workaround for the 440EPx/GRx 3410 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3411 be touched. 3412 3413 WARNING: Please make sure that this value is a multiple of 3414 the Linux page size (normally 4k). If this is not the case, 3415 then the end address of the Linux memory will be located at a 3416 non page size aligned address and this could cause major 3417 problems. 3418 3419- CONFIG_SYS_LOADS_BAUD_CHANGE: 3420 Enable temporary baudrate change while serial download 3421 3422- CONFIG_SYS_SDRAM_BASE: 3423 Physical start address of SDRAM. _Must_ be 0 here. 3424 3425- CONFIG_SYS_FLASH_BASE: 3426 Physical start address of Flash memory. 3427 3428- CONFIG_SYS_MONITOR_BASE: 3429 Physical start address of boot monitor code (set by 3430 make config files to be same as the text base address 3431 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3432 CONFIG_SYS_FLASH_BASE when booting from flash. 3433 3434- CONFIG_SYS_MONITOR_LEN: 3435 Size of memory reserved for monitor code, used to 3436 determine _at_compile_time_ (!) if the environment is 3437 embedded within the U-Boot image, or in a separate 3438 flash sector. 3439 3440- CONFIG_SYS_MALLOC_LEN: 3441 Size of DRAM reserved for malloc() use. 3442 3443- CONFIG_SYS_MALLOC_F_LEN 3444 Size of the malloc() pool for use before relocation. If 3445 this is defined, then a very simple malloc() implementation 3446 will become available before relocation. The address is just 3447 below the global data, and the stack is moved down to make 3448 space. 3449 3450 This feature allocates regions with increasing addresses 3451 within the region. calloc() is supported, but realloc() 3452 is not available. free() is supported but does nothing. 3453 The memory will be freed (or in fact just forgotten) when 3454 U-Boot relocates itself. 3455 3456- CONFIG_SYS_MALLOC_SIMPLE 3457 Provides a simple and small malloc() and calloc() for those 3458 boards which do not use the full malloc in SPL (which is 3459 enabled with CONFIG_SYS_SPL_MALLOC_START). 3460 3461- CONFIG_SYS_NONCACHED_MEMORY: 3462 Size of non-cached memory area. This area of memory will be 3463 typically located right below the malloc() area and mapped 3464 uncached in the MMU. This is useful for drivers that would 3465 otherwise require a lot of explicit cache maintenance. For 3466 some drivers it's also impossible to properly maintain the 3467 cache. For example if the regions that need to be flushed 3468 are not a multiple of the cache-line size, *and* padding 3469 cannot be allocated between the regions to align them (i.e. 3470 if the HW requires a contiguous array of regions, and the 3471 size of each region is not cache-aligned), then a flush of 3472 one region may result in overwriting data that hardware has 3473 written to another region in the same cache-line. This can 3474 happen for example in network drivers where descriptors for 3475 buffers are typically smaller than the CPU cache-line (e.g. 3476 16 bytes vs. 32 or 64 bytes). 3477 3478 Non-cached memory is only supported on 32-bit ARM at present. 3479 3480- CONFIG_SYS_BOOTM_LEN: 3481 Normally compressed uImages are limited to an 3482 uncompressed size of 8 MBytes. If this is not enough, 3483 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3484 to adjust this setting to your needs. 3485 3486- CONFIG_SYS_BOOTMAPSZ: 3487 Maximum size of memory mapped by the startup code of 3488 the Linux kernel; all data that must be processed by 3489 the Linux kernel (bd_info, boot arguments, FDT blob if 3490 used) must be put below this limit, unless "bootm_low" 3491 environment variable is defined and non-zero. In such case 3492 all data for the Linux kernel must be between "bootm_low" 3493 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3494 variable "bootm_mapsize" will override the value of 3495 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3496 then the value in "bootm_size" will be used instead. 3497 3498- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3499 Enable initrd_high functionality. If defined then the 3500 initrd_high feature is enabled and the bootm ramdisk subcommand 3501 is enabled. 3502 3503- CONFIG_SYS_BOOT_GET_CMDLINE: 3504 Enables allocating and saving kernel cmdline in space between 3505 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3506 3507- CONFIG_SYS_BOOT_GET_KBD: 3508 Enables allocating and saving a kernel copy of the bd_info in 3509 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3510 3511- CONFIG_SYS_MAX_FLASH_BANKS: 3512 Max number of Flash memory banks 3513 3514- CONFIG_SYS_MAX_FLASH_SECT: 3515 Max number of sectors on a Flash chip 3516 3517- CONFIG_SYS_FLASH_ERASE_TOUT: 3518 Timeout for Flash erase operations (in ms) 3519 3520- CONFIG_SYS_FLASH_WRITE_TOUT: 3521 Timeout for Flash write operations (in ms) 3522 3523- CONFIG_SYS_FLASH_LOCK_TOUT 3524 Timeout for Flash set sector lock bit operation (in ms) 3525 3526- CONFIG_SYS_FLASH_UNLOCK_TOUT 3527 Timeout for Flash clear lock bits operation (in ms) 3528 3529- CONFIG_SYS_FLASH_PROTECTION 3530 If defined, hardware flash sectors protection is used 3531 instead of U-Boot software protection. 3532 3533- CONFIG_SYS_DIRECT_FLASH_TFTP: 3534 3535 Enable TFTP transfers directly to flash memory; 3536 without this option such a download has to be 3537 performed in two steps: (1) download to RAM, and (2) 3538 copy from RAM to flash. 3539 3540 The two-step approach is usually more reliable, since 3541 you can check if the download worked before you erase 3542 the flash, but in some situations (when system RAM is 3543 too limited to allow for a temporary copy of the 3544 downloaded image) this option may be very useful. 3545 3546- CONFIG_SYS_FLASH_CFI: 3547 Define if the flash driver uses extra elements in the 3548 common flash structure for storing flash geometry. 3549 3550- CONFIG_FLASH_CFI_DRIVER 3551 This option also enables the building of the cfi_flash driver 3552 in the drivers directory 3553 3554- CONFIG_FLASH_CFI_MTD 3555 This option enables the building of the cfi_mtd driver 3556 in the drivers directory. The driver exports CFI flash 3557 to the MTD layer. 3558 3559- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3560 Use buffered writes to flash. 3561 3562- CONFIG_FLASH_SPANSION_S29WS_N 3563 s29ws-n MirrorBit flash has non-standard addresses for buffered 3564 write commands. 3565 3566- CONFIG_SYS_FLASH_QUIET_TEST 3567 If this option is defined, the common CFI flash doesn't 3568 print it's warning upon not recognized FLASH banks. This 3569 is useful, if some of the configured banks are only 3570 optionally available. 3571 3572- CONFIG_FLASH_SHOW_PROGRESS 3573 If defined (must be an integer), print out countdown 3574 digits and dots. Recommended value: 45 (9..1) for 80 3575 column displays, 15 (3..1) for 40 column displays. 3576 3577- CONFIG_FLASH_VERIFY 3578 If defined, the content of the flash (destination) is compared 3579 against the source after the write operation. An error message 3580 will be printed when the contents are not identical. 3581 Please note that this option is useless in nearly all cases, 3582 since such flash programming errors usually are detected earlier 3583 while unprotecting/erasing/programming. Please only enable 3584 this option if you really know what you are doing. 3585 3586- CONFIG_SYS_RX_ETH_BUFFER: 3587 Defines the number of Ethernet receive buffers. On some 3588 Ethernet controllers it is recommended to set this value 3589 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3590 buffers can be full shortly after enabling the interface 3591 on high Ethernet traffic. 3592 Defaults to 4 if not defined. 3593 3594- CONFIG_ENV_MAX_ENTRIES 3595 3596 Maximum number of entries in the hash table that is used 3597 internally to store the environment settings. The default 3598 setting is supposed to be generous and should work in most 3599 cases. This setting can be used to tune behaviour; see 3600 lib/hashtable.c for details. 3601 3602- CONFIG_ENV_FLAGS_LIST_DEFAULT 3603- CONFIG_ENV_FLAGS_LIST_STATIC 3604 Enable validation of the values given to environment variables when 3605 calling env set. Variables can be restricted to only decimal, 3606 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3607 the variables can also be restricted to IP address or MAC address. 3608 3609 The format of the list is: 3610 type_attribute = [s|d|x|b|i|m] 3611 access_attribute = [a|r|o|c] 3612 attributes = type_attribute[access_attribute] 3613 entry = variable_name[:attributes] 3614 list = entry[,list] 3615 3616 The type attributes are: 3617 s - String (default) 3618 d - Decimal 3619 x - Hexadecimal 3620 b - Boolean ([1yYtT|0nNfF]) 3621 i - IP address 3622 m - MAC address 3623 3624 The access attributes are: 3625 a - Any (default) 3626 r - Read-only 3627 o - Write-once 3628 c - Change-default 3629 3630 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3631 Define this to a list (string) to define the ".flags" 3632 environment variable in the default or embedded environment. 3633 3634 - CONFIG_ENV_FLAGS_LIST_STATIC 3635 Define this to a list (string) to define validation that 3636 should be done if an entry is not found in the ".flags" 3637 environment variable. To override a setting in the static 3638 list, simply add an entry for the same variable name to the 3639 ".flags" variable. 3640 3641 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3642 regular expression. This allows multiple variables to define the same 3643 flags without explicitly listing them for each variable. 3644 3645- CONFIG_ENV_ACCESS_IGNORE_FORCE 3646 If defined, don't allow the -f switch to env set override variable 3647 access flags. 3648 3649- CONFIG_USE_STDINT 3650 If stdint.h is available with your toolchain you can define this 3651 option to enable it. You can provide option 'USE_STDINT=1' when 3652 building U-Boot to enable this. 3653 3654The following definitions that deal with the placement and management 3655of environment data (variable area); in general, we support the 3656following configurations: 3657 3658- CONFIG_BUILD_ENVCRC: 3659 3660 Builds up envcrc with the target environment so that external utils 3661 may easily extract it and embed it in final U-Boot images. 3662 3663- CONFIG_ENV_IS_IN_FLASH: 3664 3665 Define this if the environment is in flash memory. 3666 3667 a) The environment occupies one whole flash sector, which is 3668 "embedded" in the text segment with the U-Boot code. This 3669 happens usually with "bottom boot sector" or "top boot 3670 sector" type flash chips, which have several smaller 3671 sectors at the start or the end. For instance, such a 3672 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3673 such a case you would place the environment in one of the 3674 4 kB sectors - with U-Boot code before and after it. With 3675 "top boot sector" type flash chips, you would put the 3676 environment in one of the last sectors, leaving a gap 3677 between U-Boot and the environment. 3678 3679 - CONFIG_ENV_OFFSET: 3680 3681 Offset of environment data (variable area) to the 3682 beginning of flash memory; for instance, with bottom boot 3683 type flash chips the second sector can be used: the offset 3684 for this sector is given here. 3685 3686 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3687 3688 - CONFIG_ENV_ADDR: 3689 3690 This is just another way to specify the start address of 3691 the flash sector containing the environment (instead of 3692 CONFIG_ENV_OFFSET). 3693 3694 - CONFIG_ENV_SECT_SIZE: 3695 3696 Size of the sector containing the environment. 3697 3698 3699 b) Sometimes flash chips have few, equal sized, BIG sectors. 3700 In such a case you don't want to spend a whole sector for 3701 the environment. 3702 3703 - CONFIG_ENV_SIZE: 3704 3705 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3706 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3707 of this flash sector for the environment. This saves 3708 memory for the RAM copy of the environment. 3709 3710 It may also save flash memory if you decide to use this 3711 when your environment is "embedded" within U-Boot code, 3712 since then the remainder of the flash sector could be used 3713 for U-Boot code. It should be pointed out that this is 3714 STRONGLY DISCOURAGED from a robustness point of view: 3715 updating the environment in flash makes it always 3716 necessary to erase the WHOLE sector. If something goes 3717 wrong before the contents has been restored from a copy in 3718 RAM, your target system will be dead. 3719 3720 - CONFIG_ENV_ADDR_REDUND 3721 CONFIG_ENV_SIZE_REDUND 3722 3723 These settings describe a second storage area used to hold 3724 a redundant copy of the environment data, so that there is 3725 a valid backup copy in case there is a power failure during 3726 a "saveenv" operation. 3727 3728BE CAREFUL! Any changes to the flash layout, and some changes to the 3729source code will make it necessary to adapt <board>/u-boot.lds* 3730accordingly! 3731 3732 3733- CONFIG_ENV_IS_IN_NVRAM: 3734 3735 Define this if you have some non-volatile memory device 3736 (NVRAM, battery buffered SRAM) which you want to use for the 3737 environment. 3738 3739 - CONFIG_ENV_ADDR: 3740 - CONFIG_ENV_SIZE: 3741 3742 These two #defines are used to determine the memory area you 3743 want to use for environment. It is assumed that this memory 3744 can just be read and written to, without any special 3745 provision. 3746 3747BE CAREFUL! The first access to the environment happens quite early 3748in U-Boot initialization (when we try to get the setting of for the 3749console baudrate). You *MUST* have mapped your NVRAM area then, or 3750U-Boot will hang. 3751 3752Please note that even with NVRAM we still use a copy of the 3753environment in RAM: we could work on NVRAM directly, but we want to 3754keep settings there always unmodified except somebody uses "saveenv" 3755to save the current settings. 3756 3757 3758- CONFIG_ENV_IS_IN_EEPROM: 3759 3760 Use this if you have an EEPROM or similar serial access 3761 device and a driver for it. 3762 3763 - CONFIG_ENV_OFFSET: 3764 - CONFIG_ENV_SIZE: 3765 3766 These two #defines specify the offset and size of the 3767 environment area within the total memory of your EEPROM. 3768 3769 - CONFIG_SYS_I2C_EEPROM_ADDR: 3770 If defined, specified the chip address of the EEPROM device. 3771 The default address is zero. 3772 3773 - CONFIG_SYS_I2C_EEPROM_BUS: 3774 If defined, specified the i2c bus of the EEPROM device. 3775 3776 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3777 If defined, the number of bits used to address bytes in a 3778 single page in the EEPROM device. A 64 byte page, for example 3779 would require six bits. 3780 3781 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3782 If defined, the number of milliseconds to delay between 3783 page writes. The default is zero milliseconds. 3784 3785 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3786 The length in bytes of the EEPROM memory array address. Note 3787 that this is NOT the chip address length! 3788 3789 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3790 EEPROM chips that implement "address overflow" are ones 3791 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3792 address and the extra bits end up in the "chip address" bit 3793 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3794 byte chips. 3795 3796 Note that we consider the length of the address field to 3797 still be one byte because the extra address bits are hidden 3798 in the chip address. 3799 3800 - CONFIG_SYS_EEPROM_SIZE: 3801 The size in bytes of the EEPROM device. 3802 3803 - CONFIG_ENV_EEPROM_IS_ON_I2C 3804 define this, if you have I2C and SPI activated, and your 3805 EEPROM, which holds the environment, is on the I2C bus. 3806 3807 - CONFIG_I2C_ENV_EEPROM_BUS 3808 if you have an Environment on an EEPROM reached over 3809 I2C muxes, you can define here, how to reach this 3810 EEPROM. For example: 3811 3812 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3813 3814 EEPROM which holds the environment, is reached over 3815 a pca9547 i2c mux with address 0x70, channel 3. 3816 3817- CONFIG_ENV_IS_IN_DATAFLASH: 3818 3819 Define this if you have a DataFlash memory device which you 3820 want to use for the environment. 3821 3822 - CONFIG_ENV_OFFSET: 3823 - CONFIG_ENV_ADDR: 3824 - CONFIG_ENV_SIZE: 3825 3826 These three #defines specify the offset and size of the 3827 environment area within the total memory of your DataFlash placed 3828 at the specified address. 3829 3830- CONFIG_ENV_IS_IN_SPI_FLASH: 3831 3832 Define this if you have a SPI Flash memory device which you 3833 want to use for the environment. 3834 3835 - CONFIG_ENV_OFFSET: 3836 - CONFIG_ENV_SIZE: 3837 3838 These two #defines specify the offset and size of the 3839 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 3840 aligned to an erase sector boundary. 3841 3842 - CONFIG_ENV_SECT_SIZE: 3843 3844 Define the SPI flash's sector size. 3845 3846 - CONFIG_ENV_OFFSET_REDUND (optional): 3847 3848 This setting describes a second storage area of CONFIG_ENV_SIZE 3849 size used to hold a redundant copy of the environment data, so 3850 that there is a valid backup copy in case there is a power failure 3851 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3852 aligned to an erase sector boundary. 3853 3854 - CONFIG_ENV_SPI_BUS (optional): 3855 - CONFIG_ENV_SPI_CS (optional): 3856 3857 Define the SPI bus and chip select. If not defined they will be 0. 3858 3859 - CONFIG_ENV_SPI_MAX_HZ (optional): 3860 3861 Define the SPI max work clock. If not defined then use 1MHz. 3862 3863 - CONFIG_ENV_SPI_MODE (optional): 3864 3865 Define the SPI work mode. If not defined then use SPI_MODE_3. 3866 3867- CONFIG_ENV_IS_IN_REMOTE: 3868 3869 Define this if you have a remote memory space which you 3870 want to use for the local device's environment. 3871 3872 - CONFIG_ENV_ADDR: 3873 - CONFIG_ENV_SIZE: 3874 3875 These two #defines specify the address and size of the 3876 environment area within the remote memory space. The 3877 local device can get the environment from remote memory 3878 space by SRIO or PCIE links. 3879 3880BE CAREFUL! For some special cases, the local device can not use 3881"saveenv" command. For example, the local device will get the 3882environment stored in a remote NOR flash by SRIO or PCIE link, 3883but it can not erase, write this NOR flash by SRIO or PCIE interface. 3884 3885- CONFIG_ENV_IS_IN_NAND: 3886 3887 Define this if you have a NAND device which you want to use 3888 for the environment. 3889 3890 - CONFIG_ENV_OFFSET: 3891 - CONFIG_ENV_SIZE: 3892 3893 These two #defines specify the offset and size of the environment 3894 area within the first NAND device. CONFIG_ENV_OFFSET must be 3895 aligned to an erase block boundary. 3896 3897 - CONFIG_ENV_OFFSET_REDUND (optional): 3898 3899 This setting describes a second storage area of CONFIG_ENV_SIZE 3900 size used to hold a redundant copy of the environment data, so 3901 that there is a valid backup copy in case there is a power failure 3902 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3903 aligned to an erase block boundary. 3904 3905 - CONFIG_ENV_RANGE (optional): 3906 3907 Specifies the length of the region in which the environment 3908 can be written. This should be a multiple of the NAND device's 3909 block size. Specifying a range with more erase blocks than 3910 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3911 the range to be avoided. 3912 3913 - CONFIG_ENV_OFFSET_OOB (optional): 3914 3915 Enables support for dynamically retrieving the offset of the 3916 environment from block zero's out-of-band data. The 3917 "nand env.oob" command can be used to record this offset. 3918 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 3919 using CONFIG_ENV_OFFSET_OOB. 3920 3921- CONFIG_NAND_ENV_DST 3922 3923 Defines address in RAM to which the nand_spl code should copy the 3924 environment. If redundant environment is used, it will be copied to 3925 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3926 3927- CONFIG_ENV_IS_IN_UBI: 3928 3929 Define this if you have an UBI volume that you want to use for the 3930 environment. This has the benefit of wear-leveling the environment 3931 accesses, which is important on NAND. 3932 3933 - CONFIG_ENV_UBI_PART: 3934 3935 Define this to a string that is the mtd partition containing the UBI. 3936 3937 - CONFIG_ENV_UBI_VOLUME: 3938 3939 Define this to the name of the volume that you want to store the 3940 environment in. 3941 3942 - CONFIG_ENV_UBI_VOLUME_REDUND: 3943 3944 Define this to the name of another volume to store a second copy of 3945 the environment in. This will enable redundant environments in UBI. 3946 It is assumed that both volumes are in the same MTD partition. 3947 3948 - CONFIG_UBI_SILENCE_MSG 3949 - CONFIG_UBIFS_SILENCE_MSG 3950 3951 You will probably want to define these to avoid a really noisy system 3952 when storing the env in UBI. 3953 3954- CONFIG_ENV_IS_IN_FAT: 3955 Define this if you want to use the FAT file system for the environment. 3956 3957 - FAT_ENV_INTERFACE: 3958 3959 Define this to a string that is the name of the block device. 3960 3961 - FAT_ENV_DEVICE_AND_PART: 3962 3963 Define this to a string to specify the partition of the device. It can 3964 be as following: 3965 3966 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 3967 - "D:P": device D partition P. Error occurs if device D has no 3968 partition table. 3969 - "D:0": device D. 3970 - "D" or "D:": device D partition 1 if device D has partition 3971 table, or the whole device D if has no partition 3972 table. 3973 - "D:auto": first partition in device D with bootable flag set. 3974 If none, first valid partition in device D. If no 3975 partition table then means device D. 3976 3977 - FAT_ENV_FILE: 3978 3979 It's a string of the FAT file name. This file use to store the 3980 environment. 3981 3982 - CONFIG_FAT_WRITE: 3983 This should be defined. Otherwise it cannot save the environment file. 3984 3985- CONFIG_ENV_IS_IN_MMC: 3986 3987 Define this if you have an MMC device which you want to use for the 3988 environment. 3989 3990 - CONFIG_SYS_MMC_ENV_DEV: 3991 3992 Specifies which MMC device the environment is stored in. 3993 3994 - CONFIG_SYS_MMC_ENV_PART (optional): 3995 3996 Specifies which MMC partition the environment is stored in. If not 3997 set, defaults to partition 0, the user area. Common values might be 3998 1 (first MMC boot partition), 2 (second MMC boot partition). 3999 4000 - CONFIG_ENV_OFFSET: 4001 - CONFIG_ENV_SIZE: 4002 4003 These two #defines specify the offset and size of the environment 4004 area within the specified MMC device. 4005 4006 If offset is positive (the usual case), it is treated as relative to 4007 the start of the MMC partition. If offset is negative, it is treated 4008 as relative to the end of the MMC partition. This can be useful if 4009 your board may be fitted with different MMC devices, which have 4010 different sizes for the MMC partitions, and you always want the 4011 environment placed at the very end of the partition, to leave the 4012 maximum possible space before it, to store other data. 4013 4014 These two values are in units of bytes, but must be aligned to an 4015 MMC sector boundary. 4016 4017 - CONFIG_ENV_OFFSET_REDUND (optional): 4018 4019 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4020 hold a redundant copy of the environment data. This provides a 4021 valid backup copy in case the other copy is corrupted, e.g. due 4022 to a power failure during a "saveenv" operation. 4023 4024 This value may also be positive or negative; this is handled in the 4025 same way as CONFIG_ENV_OFFSET. 4026 4027 This value is also in units of bytes, but must also be aligned to 4028 an MMC sector boundary. 4029 4030 - CONFIG_ENV_SIZE_REDUND (optional): 4031 4032 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4033 set. If this value is set, it must be set to the same value as 4034 CONFIG_ENV_SIZE. 4035 4036- CONFIG_SYS_SPI_INIT_OFFSET 4037 4038 Defines offset to the initial SPI buffer area in DPRAM. The 4039 area is used at an early stage (ROM part) if the environment 4040 is configured to reside in the SPI EEPROM: We need a 520 byte 4041 scratch DPRAM area. It is used between the two initialization 4042 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4043 to be a good choice since it makes it far enough from the 4044 start of the data area as well as from the stack pointer. 4045 4046Please note that the environment is read-only until the monitor 4047has been relocated to RAM and a RAM copy of the environment has been 4048created; also, when using EEPROM you will have to use getenv_f() 4049until then to read environment variables. 4050 4051The environment is protected by a CRC32 checksum. Before the monitor 4052is relocated into RAM, as a result of a bad CRC you will be working 4053with the compiled-in default environment - *silently*!!! [This is 4054necessary, because the first environment variable we need is the 4055"baudrate" setting for the console - if we have a bad CRC, we don't 4056have any device yet where we could complain.] 4057 4058Note: once the monitor has been relocated, then it will complain if 4059the default environment is used; a new CRC is computed as soon as you 4060use the "saveenv" command to store a valid environment. 4061 4062- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4063 Echo the inverted Ethernet link state to the fault LED. 4064 4065 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4066 also needs to be defined. 4067 4068- CONFIG_SYS_FAULT_MII_ADDR: 4069 MII address of the PHY to check for the Ethernet link state. 4070 4071- CONFIG_NS16550_MIN_FUNCTIONS: 4072 Define this if you desire to only have use of the NS16550_init 4073 and NS16550_putc functions for the serial driver located at 4074 drivers/serial/ns16550.c. This option is useful for saving 4075 space for already greatly restricted images, including but not 4076 limited to NAND_SPL configurations. 4077 4078- CONFIG_DISPLAY_BOARDINFO 4079 Display information about the board that U-Boot is running on 4080 when U-Boot starts up. The board function checkboard() is called 4081 to do this. 4082 4083- CONFIG_DISPLAY_BOARDINFO_LATE 4084 Similar to the previous option, but display this information 4085 later, once stdio is running and output goes to the LCD, if 4086 present. 4087 4088- CONFIG_BOARD_SIZE_LIMIT: 4089 Maximum size of the U-Boot image. When defined, the 4090 build system checks that the actual size does not 4091 exceed it. 4092 4093Low Level (hardware related) configuration options: 4094--------------------------------------------------- 4095 4096- CONFIG_SYS_CACHELINE_SIZE: 4097 Cache Line Size of the CPU. 4098 4099- CONFIG_SYS_DEFAULT_IMMR: 4100 Default address of the IMMR after system reset. 4101 4102 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4103 and RPXsuper) to be able to adjust the position of 4104 the IMMR register after a reset. 4105 4106- CONFIG_SYS_CCSRBAR_DEFAULT: 4107 Default (power-on reset) physical address of CCSR on Freescale 4108 PowerPC SOCs. 4109 4110- CONFIG_SYS_CCSRBAR: 4111 Virtual address of CCSR. On a 32-bit build, this is typically 4112 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4113 4114 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4115 for cross-platform code that uses that macro instead. 4116 4117- CONFIG_SYS_CCSRBAR_PHYS: 4118 Physical address of CCSR. CCSR can be relocated to a new 4119 physical address, if desired. In this case, this macro should 4120 be set to that address. Otherwise, it should be set to the 4121 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4122 is typically relocated on 36-bit builds. It is recommended 4123 that this macro be defined via the _HIGH and _LOW macros: 4124 4125 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4126 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4127 4128- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4129 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4130 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4131 used in assembly code, so it must not contain typecasts or 4132 integer size suffixes (e.g. "ULL"). 4133 4134- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4135 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4136 used in assembly code, so it must not contain typecasts or 4137 integer size suffixes (e.g. "ULL"). 4138 4139- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4140 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4141 forced to a value that ensures that CCSR is not relocated. 4142 4143- Floppy Disk Support: 4144 CONFIG_SYS_FDC_DRIVE_NUMBER 4145 4146 the default drive number (default value 0) 4147 4148 CONFIG_SYS_ISA_IO_STRIDE 4149 4150 defines the spacing between FDC chipset registers 4151 (default value 1) 4152 4153 CONFIG_SYS_ISA_IO_OFFSET 4154 4155 defines the offset of register from address. It 4156 depends on which part of the data bus is connected to 4157 the FDC chipset. (default value 0) 4158 4159 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4160 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4161 default value. 4162 4163 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4164 fdc_hw_init() is called at the beginning of the FDC 4165 setup. fdc_hw_init() must be provided by the board 4166 source code. It is used to make hardware-dependent 4167 initializations. 4168 4169- CONFIG_IDE_AHB: 4170 Most IDE controllers were designed to be connected with PCI 4171 interface. Only few of them were designed for AHB interface. 4172 When software is doing ATA command and data transfer to 4173 IDE devices through IDE-AHB controller, some additional 4174 registers accessing to these kind of IDE-AHB controller 4175 is required. 4176 4177- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4178 DO NOT CHANGE unless you know exactly what you're 4179 doing! (11-4) [MPC8xx/82xx systems only] 4180 4181- CONFIG_SYS_INIT_RAM_ADDR: 4182 4183 Start address of memory area that can be used for 4184 initial data and stack; please note that this must be 4185 writable memory that is working WITHOUT special 4186 initialization, i. e. you CANNOT use normal RAM which 4187 will become available only after programming the 4188 memory controller and running certain initialization 4189 sequences. 4190 4191 U-Boot uses the following memory types: 4192 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4193 - MPC824X: data cache 4194 - PPC4xx: data cache 4195 4196- CONFIG_SYS_GBL_DATA_OFFSET: 4197 4198 Offset of the initial data structure in the memory 4199 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4200 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4201 data is located at the end of the available space 4202 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4203 GENERATED_GBL_DATA_SIZE), and the initial stack is just 4204 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4205 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4206 4207 Note: 4208 On the MPC824X (or other systems that use the data 4209 cache for initial memory) the address chosen for 4210 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4211 point to an otherwise UNUSED address space between 4212 the top of RAM and the start of the PCI space. 4213 4214- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4215 4216- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4217 4218- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4219 4220- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4221 4222- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4223 4224- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4225 4226- CONFIG_SYS_OR_TIMING_SDRAM: 4227 SDRAM timing 4228 4229- CONFIG_SYS_MAMR_PTA: 4230 periodic timer for refresh 4231 4232- CONFIG_SYS_DER: Debug Event Register (37-47) 4233 4234- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4235 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4236 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4237 CONFIG_SYS_BR1_PRELIM: 4238 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4239 4240- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4241 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4242 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4243 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4244 4245- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4246 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4247 Machine Mode Register and Memory Periodic Timer 4248 Prescaler definitions (SDRAM timing) 4249 4250- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4251 enable I2C microcode relocation patch (MPC8xx); 4252 define relocation offset in DPRAM [DSP2] 4253 4254- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4255 enable SMC microcode relocation patch (MPC8xx); 4256 define relocation offset in DPRAM [SMC1] 4257 4258- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4259 enable SPI microcode relocation patch (MPC8xx); 4260 define relocation offset in DPRAM [SCC4] 4261 4262- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4263 Offset of the bootmode word in DPRAM used by post 4264 (Power On Self Tests). This definition overrides 4265 #define'd default value in commproc.h resp. 4266 cpm_8260.h. 4267 4268- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4269 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4270 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4271 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4272 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4273 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4274 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4275 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4276 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4277 4278- CONFIG_PCI_DISABLE_PCIE: 4279 Disable PCI-Express on systems where it is supported but not 4280 required. 4281 4282- CONFIG_PCI_ENUM_ONLY 4283 Only scan through and get the devices on the buses. 4284 Don't do any setup work, presumably because someone or 4285 something has already done it, and we don't need to do it 4286 a second time. Useful for platforms that are pre-booted 4287 by coreboot or similar. 4288 4289- CONFIG_PCI_INDIRECT_BRIDGE: 4290 Enable support for indirect PCI bridges. 4291 4292- CONFIG_SYS_SRIO: 4293 Chip has SRIO or not 4294 4295- CONFIG_SRIO1: 4296 Board has SRIO 1 port available 4297 4298- CONFIG_SRIO2: 4299 Board has SRIO 2 port available 4300 4301- CONFIG_SRIO_PCIE_BOOT_MASTER 4302 Board can support master function for Boot from SRIO and PCIE 4303 4304- CONFIG_SYS_SRIOn_MEM_VIRT: 4305 Virtual Address of SRIO port 'n' memory region 4306 4307- CONFIG_SYS_SRIOn_MEM_PHYS: 4308 Physical Address of SRIO port 'n' memory region 4309 4310- CONFIG_SYS_SRIOn_MEM_SIZE: 4311 Size of SRIO port 'n' memory region 4312 4313- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4314 Defined to tell the NAND controller that the NAND chip is using 4315 a 16 bit bus. 4316 Not all NAND drivers use this symbol. 4317 Example of drivers that use it: 4318 - drivers/mtd/nand/ndfc.c 4319 - drivers/mtd/nand/mxc_nand.c 4320 4321- CONFIG_SYS_NDFC_EBC0_CFG 4322 Sets the EBC0_CFG register for the NDFC. If not defined 4323 a default value will be used. 4324 4325- CONFIG_SPD_EEPROM 4326 Get DDR timing information from an I2C EEPROM. Common 4327 with pluggable memory modules such as SODIMMs 4328 4329 SPD_EEPROM_ADDRESS 4330 I2C address of the SPD EEPROM 4331 4332- CONFIG_SYS_SPD_BUS_NUM 4333 If SPD EEPROM is on an I2C bus other than the first 4334 one, specify here. Note that the value must resolve 4335 to something your driver can deal with. 4336 4337- CONFIG_SYS_DDR_RAW_TIMING 4338 Get DDR timing information from other than SPD. Common with 4339 soldered DDR chips onboard without SPD. DDR raw timing 4340 parameters are extracted from datasheet and hard-coded into 4341 header files or board specific files. 4342 4343- CONFIG_FSL_DDR_INTERACTIVE 4344 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4345 4346- CONFIG_FSL_DDR_SYNC_REFRESH 4347 Enable sync of refresh for multiple controllers. 4348 4349- CONFIG_FSL_DDR_BIST 4350 Enable built-in memory test for Freescale DDR controllers. 4351 4352- CONFIG_SYS_83XX_DDR_USES_CS0 4353 Only for 83xx systems. If specified, then DDR should 4354 be configured using CS0 and CS1 instead of CS2 and CS3. 4355 4356- CONFIG_ETHER_ON_FEC[12] 4357 Define to enable FEC[12] on a 8xx series processor. 4358 4359- CONFIG_FEC[12]_PHY 4360 Define to the hardcoded PHY address which corresponds 4361 to the given FEC; i. e. 4362 #define CONFIG_FEC1_PHY 4 4363 means that the PHY with address 4 is connected to FEC1 4364 4365 When set to -1, means to probe for first available. 4366 4367- CONFIG_FEC[12]_PHY_NORXERR 4368 The PHY does not have a RXERR line (RMII only). 4369 (so program the FEC to ignore it). 4370 4371- CONFIG_RMII 4372 Enable RMII mode for all FECs. 4373 Note that this is a global option, we can't 4374 have one FEC in standard MII mode and another in RMII mode. 4375 4376- CONFIG_CRC32_VERIFY 4377 Add a verify option to the crc32 command. 4378 The syntax is: 4379 4380 => crc32 -v <address> <count> <crc32> 4381 4382 Where address/count indicate a memory area 4383 and crc32 is the correct crc32 which the 4384 area should have. 4385 4386- CONFIG_LOOPW 4387 Add the "loopw" memory command. This only takes effect if 4388 the memory commands are activated globally (CONFIG_CMD_MEM). 4389 4390- CONFIG_MX_CYCLIC 4391 Add the "mdc" and "mwc" memory commands. These are cyclic 4392 "md/mw" commands. 4393 Examples: 4394 4395 => mdc.b 10 4 500 4396 This command will print 4 bytes (10,11,12,13) each 500 ms. 4397 4398 => mwc.l 100 12345678 10 4399 This command will write 12345678 to address 100 all 10 ms. 4400 4401 This only takes effect if the memory commands are activated 4402 globally (CONFIG_CMD_MEM). 4403 4404- CONFIG_SKIP_LOWLEVEL_INIT 4405 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4406 low level initializations (like setting up the memory 4407 controller) are omitted and/or U-Boot does not 4408 relocate itself into RAM. 4409 4410 Normally this variable MUST NOT be defined. The only 4411 exception is when U-Boot is loaded (to RAM) by some 4412 other boot loader or by a debugger which performs 4413 these initializations itself. 4414 4415- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 4416 [ARM926EJ-S only] This allows just the call to lowlevel_init() 4417 to be skipped. The normal CP15 init (such as enabling the 4418 instruction cache) is still performed. 4419 4420- CONFIG_SPL_BUILD 4421 Modifies the behaviour of start.S when compiling a loader 4422 that is executed before the actual U-Boot. E.g. when 4423 compiling a NAND SPL. 4424 4425- CONFIG_TPL_BUILD 4426 Modifies the behaviour of start.S when compiling a loader 4427 that is executed after the SPL and before the actual U-Boot. 4428 It is loaded by the SPL. 4429 4430- CONFIG_SYS_MPC85XX_NO_RESETVEC 4431 Only for 85xx systems. If this variable is specified, the section 4432 .resetvec is not kept and the section .bootpg is placed in the 4433 previous 4k of the .text section. 4434 4435- CONFIG_ARCH_MAP_SYSMEM 4436 Generally U-Boot (and in particular the md command) uses 4437 effective address. It is therefore not necessary to regard 4438 U-Boot address as virtual addresses that need to be translated 4439 to physical addresses. However, sandbox requires this, since 4440 it maintains its own little RAM buffer which contains all 4441 addressable memory. This option causes some memory accesses 4442 to be mapped through map_sysmem() / unmap_sysmem(). 4443 4444- CONFIG_X86_RESET_VECTOR 4445 If defined, the x86 reset vector code is included. This is not 4446 needed when U-Boot is running from Coreboot. 4447 4448- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4449 Enables the RTC32K OSC on AM33xx based plattforms 4450 4451- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4452 Option to disable subpage write in NAND driver 4453 driver that uses this: 4454 drivers/mtd/nand/davinci_nand.c 4455 4456Freescale QE/FMAN Firmware Support: 4457----------------------------------- 4458 4459The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4460loading of "firmware", which is encoded in the QE firmware binary format. 4461This firmware often needs to be loaded during U-Boot booting, so macros 4462are used to identify the storage device (NOR flash, SPI, etc) and the address 4463within that device. 4464 4465- CONFIG_SYS_FMAN_FW_ADDR 4466 The address in the storage device where the FMAN microcode is located. The 4467 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4468 is also specified. 4469 4470- CONFIG_SYS_QE_FW_ADDR 4471 The address in the storage device where the QE microcode is located. The 4472 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4473 is also specified. 4474 4475- CONFIG_SYS_QE_FMAN_FW_LENGTH 4476 The maximum possible size of the firmware. The firmware binary format 4477 has a field that specifies the actual size of the firmware, but it 4478 might not be possible to read any part of the firmware unless some 4479 local storage is allocated to hold the entire firmware first. 4480 4481- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4482 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4483 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4484 virtual address in NOR flash. 4485 4486- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4487 Specifies that QE/FMAN firmware is located in NAND flash. 4488 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4489 4490- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4491 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4492 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4493 4494- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4495 Specifies that QE/FMAN firmware is located in the remote (master) 4496 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4497 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4498 window->master inbound window->master LAW->the ucode address in 4499 master's memory space. 4500 4501Freescale Layerscape Management Complex Firmware Support: 4502--------------------------------------------------------- 4503The Freescale Layerscape Management Complex (MC) supports the loading of 4504"firmware". 4505This firmware often needs to be loaded during U-Boot booting, so macros 4506are used to identify the storage device (NOR flash, SPI, etc) and the address 4507within that device. 4508 4509- CONFIG_FSL_MC_ENET 4510 Enable the MC driver for Layerscape SoCs. 4511 4512Freescale Layerscape Debug Server Support: 4513------------------------------------------- 4514The Freescale Layerscape Debug Server Support supports the loading of 4515"Debug Server firmware" and triggering SP boot-rom. 4516This firmware often needs to be loaded during U-Boot booting. 4517 4518- CONFIG_SYS_MC_RSV_MEM_ALIGN 4519 Define alignment of reserved memory MC requires 4520 4521Reproducible builds 4522------------------- 4523 4524In order to achieve reproducible builds, timestamps used in the U-Boot build 4525process have to be set to a fixed value. 4526 4527This is done using the SOURCE_DATE_EPOCH environment variable. 4528SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 4529option for U-Boot or an environment variable in U-Boot. 4530 4531SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 4532 4533Building the Software: 4534====================== 4535 4536Building U-Boot has been tested in several native build environments 4537and in many different cross environments. Of course we cannot support 4538all possibly existing versions of cross development tools in all 4539(potentially obsolete) versions. In case of tool chain problems we 4540recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4541which is extensively used to build and test U-Boot. 4542 4543If you are not using a native environment, it is assumed that you 4544have GNU cross compiling tools available in your path. In this case, 4545you must set the environment variable CROSS_COMPILE in your shell. 4546Note that no changes to the Makefile or any other source files are 4547necessary. For example using the ELDK on a 4xx CPU, please enter: 4548 4549 $ CROSS_COMPILE=ppc_4xx- 4550 $ export CROSS_COMPILE 4551 4552Note: If you wish to generate Windows versions of the utilities in 4553 the tools directory you can use the MinGW toolchain 4554 (http://www.mingw.org). Set your HOST tools to the MinGW 4555 toolchain and execute 'make tools'. For example: 4556 4557 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4558 4559 Binaries such as tools/mkimage.exe will be created which can 4560 be executed on computers running Windows. 4561 4562U-Boot is intended to be simple to build. After installing the 4563sources you must configure U-Boot for one specific board type. This 4564is done by typing: 4565 4566 make NAME_defconfig 4567 4568where "NAME_defconfig" is the name of one of the existing configu- 4569rations; see boards.cfg for supported names. 4570 4571Note: for some board special configuration names may exist; check if 4572 additional information is available from the board vendor; for 4573 instance, the TQM823L systems are available without (standard) 4574 or with LCD support. You can select such additional "features" 4575 when choosing the configuration, i. e. 4576 4577 make TQM823L_defconfig 4578 - will configure for a plain TQM823L, i. e. no LCD support 4579 4580 make TQM823L_LCD_defconfig 4581 - will configure for a TQM823L with U-Boot console on LCD 4582 4583 etc. 4584 4585 4586Finally, type "make all", and you should get some working U-Boot 4587images ready for download to / installation on your system: 4588 4589- "u-boot.bin" is a raw binary image 4590- "u-boot" is an image in ELF binary format 4591- "u-boot.srec" is in Motorola S-Record format 4592 4593By default the build is performed locally and the objects are saved 4594in the source directory. One of the two methods can be used to change 4595this behavior and build U-Boot to some external directory: 4596 45971. Add O= to the make command line invocations: 4598 4599 make O=/tmp/build distclean 4600 make O=/tmp/build NAME_defconfig 4601 make O=/tmp/build all 4602 46032. Set environment variable KBUILD_OUTPUT to point to the desired location: 4604 4605 export KBUILD_OUTPUT=/tmp/build 4606 make distclean 4607 make NAME_defconfig 4608 make all 4609 4610Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 4611variable. 4612 4613 4614Please be aware that the Makefiles assume you are using GNU make, so 4615for instance on NetBSD you might need to use "gmake" instead of 4616native "make". 4617 4618 4619If the system board that you have is not listed, then you will need 4620to port U-Boot to your hardware platform. To do this, follow these 4621steps: 4622 46231. Create a new directory to hold your board specific code. Add any 4624 files you need. In your board directory, you will need at least 4625 the "Makefile" and a "<board>.c". 46262. Create a new configuration file "include/configs/<board>.h" for 4627 your board. 46283. If you're porting U-Boot to a new CPU, then also create a new 4629 directory to hold your CPU specific code. Add any files you need. 46304. Run "make <board>_defconfig" with your new name. 46315. Type "make", and you should get a working "u-boot.srec" file 4632 to be installed on your target system. 46336. Debug and solve any problems that might arise. 4634 [Of course, this last step is much harder than it sounds.] 4635 4636 4637Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4638============================================================== 4639 4640If you have modified U-Boot sources (for instance added a new board 4641or support for new devices, a new CPU, etc.) you are expected to 4642provide feedback to the other developers. The feedback normally takes 4643the form of a "patch", i. e. a context diff against a certain (latest 4644official or latest in the git repository) version of U-Boot sources. 4645 4646But before you submit such a patch, please verify that your modifi- 4647cation did not break existing code. At least make sure that *ALL* of 4648the supported boards compile WITHOUT ANY compiler warnings. To do so, 4649just run the buildman script (tools/buildman/buildman), which will 4650configure and build U-Boot for ALL supported system. Be warned, this 4651will take a while. Please see the buildman README, or run 'buildman -H' 4652for documentation. 4653 4654 4655See also "U-Boot Porting Guide" below. 4656 4657 4658Monitor Commands - Overview: 4659============================ 4660 4661go - start application at address 'addr' 4662run - run commands in an environment variable 4663bootm - boot application image from memory 4664bootp - boot image via network using BootP/TFTP protocol 4665bootz - boot zImage from memory 4666tftpboot- boot image via network using TFTP protocol 4667 and env variables "ipaddr" and "serverip" 4668 (and eventually "gatewayip") 4669tftpput - upload a file via network using TFTP protocol 4670rarpboot- boot image via network using RARP/TFTP protocol 4671diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4672loads - load S-Record file over serial line 4673loadb - load binary file over serial line (kermit mode) 4674md - memory display 4675mm - memory modify (auto-incrementing) 4676nm - memory modify (constant address) 4677mw - memory write (fill) 4678cp - memory copy 4679cmp - memory compare 4680crc32 - checksum calculation 4681i2c - I2C sub-system 4682sspi - SPI utility commands 4683base - print or set address offset 4684printenv- print environment variables 4685setenv - set environment variables 4686saveenv - save environment variables to persistent storage 4687protect - enable or disable FLASH write protection 4688erase - erase FLASH memory 4689flinfo - print FLASH memory information 4690nand - NAND memory operations (see doc/README.nand) 4691bdinfo - print Board Info structure 4692iminfo - print header information for application image 4693coninfo - print console devices and informations 4694ide - IDE sub-system 4695loop - infinite loop on address range 4696loopw - infinite write loop on address range 4697mtest - simple RAM test 4698icache - enable or disable instruction cache 4699dcache - enable or disable data cache 4700reset - Perform RESET of the CPU 4701echo - echo args to console 4702version - print monitor version 4703help - print online help 4704? - alias for 'help' 4705 4706 4707Monitor Commands - Detailed Description: 4708======================================== 4709 4710TODO. 4711 4712For now: just type "help <command>". 4713 4714 4715Environment Variables: 4716====================== 4717 4718U-Boot supports user configuration using Environment Variables which 4719can be made persistent by saving to Flash memory. 4720 4721Environment Variables are set using "setenv", printed using 4722"printenv", and saved to Flash using "saveenv". Using "setenv" 4723without a value can be used to delete a variable from the 4724environment. As long as you don't save the environment you are 4725working with an in-memory copy. In case the Flash area containing the 4726environment is erased by accident, a default environment is provided. 4727 4728Some configuration options can be set using Environment Variables. 4729 4730List of environment variables (most likely not complete): 4731 4732 baudrate - see CONFIG_BAUDRATE 4733 4734 bootdelay - see CONFIG_BOOTDELAY 4735 4736 bootcmd - see CONFIG_BOOTCOMMAND 4737 4738 bootargs - Boot arguments when booting an RTOS image 4739 4740 bootfile - Name of the image to load with TFTP 4741 4742 bootm_low - Memory range available for image processing in the bootm 4743 command can be restricted. This variable is given as 4744 a hexadecimal number and defines lowest address allowed 4745 for use by the bootm command. See also "bootm_size" 4746 environment variable. Address defined by "bootm_low" is 4747 also the base of the initial memory mapping for the Linux 4748 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4749 bootm_mapsize. 4750 4751 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4752 This variable is given as a hexadecimal number and it 4753 defines the size of the memory region starting at base 4754 address bootm_low that is accessible by the Linux kernel 4755 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4756 as the default value if it is defined, and bootm_size is 4757 used otherwise. 4758 4759 bootm_size - Memory range available for image processing in the bootm 4760 command can be restricted. This variable is given as 4761 a hexadecimal number and defines the size of the region 4762 allowed for use by the bootm command. See also "bootm_low" 4763 environment variable. 4764 4765 updatefile - Location of the software update file on a TFTP server, used 4766 by the automatic software update feature. Please refer to 4767 documentation in doc/README.update for more details. 4768 4769 autoload - if set to "no" (any string beginning with 'n'), 4770 "bootp" will just load perform a lookup of the 4771 configuration from the BOOTP server, but not try to 4772 load any image using TFTP 4773 4774 autostart - if set to "yes", an image loaded using the "bootp", 4775 "rarpboot", "tftpboot" or "diskboot" commands will 4776 be automatically started (by internally calling 4777 "bootm") 4778 4779 If set to "no", a standalone image passed to the 4780 "bootm" command will be copied to the load address 4781 (and eventually uncompressed), but NOT be started. 4782 This can be used to load and uncompress arbitrary 4783 data. 4784 4785 fdt_high - if set this restricts the maximum address that the 4786 flattened device tree will be copied into upon boot. 4787 For example, if you have a system with 1 GB memory 4788 at physical address 0x10000000, while Linux kernel 4789 only recognizes the first 704 MB as low memory, you 4790 may need to set fdt_high as 0x3C000000 to have the 4791 device tree blob be copied to the maximum address 4792 of the 704 MB low memory, so that Linux kernel can 4793 access it during the boot procedure. 4794 4795 If this is set to the special value 0xFFFFFFFF then 4796 the fdt will not be copied at all on boot. For this 4797 to work it must reside in writable memory, have 4798 sufficient padding on the end of it for u-boot to 4799 add the information it needs into it, and the memory 4800 must be accessible by the kernel. 4801 4802 fdtcontroladdr- if set this is the address of the control flattened 4803 device tree used by U-Boot when CONFIG_OF_CONTROL is 4804 defined. 4805 4806 i2cfast - (PPC405GP|PPC405EP only) 4807 if set to 'y' configures Linux I2C driver for fast 4808 mode (400kHZ). This environment variable is used in 4809 initialization code. So, for changes to be effective 4810 it must be saved and board must be reset. 4811 4812 initrd_high - restrict positioning of initrd images: 4813 If this variable is not set, initrd images will be 4814 copied to the highest possible address in RAM; this 4815 is usually what you want since it allows for 4816 maximum initrd size. If for some reason you want to 4817 make sure that the initrd image is loaded below the 4818 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4819 variable to a value of "no" or "off" or "0". 4820 Alternatively, you can set it to a maximum upper 4821 address to use (U-Boot will still check that it 4822 does not overwrite the U-Boot stack and data). 4823 4824 For instance, when you have a system with 16 MB 4825 RAM, and want to reserve 4 MB from use by Linux, 4826 you can do this by adding "mem=12M" to the value of 4827 the "bootargs" variable. However, now you must make 4828 sure that the initrd image is placed in the first 4829 12 MB as well - this can be done with 4830 4831 setenv initrd_high 00c00000 4832 4833 If you set initrd_high to 0xFFFFFFFF, this is an 4834 indication to U-Boot that all addresses are legal 4835 for the Linux kernel, including addresses in flash 4836 memory. In this case U-Boot will NOT COPY the 4837 ramdisk at all. This may be useful to reduce the 4838 boot time on your system, but requires that this 4839 feature is supported by your Linux kernel. 4840 4841 ipaddr - IP address; needed for tftpboot command 4842 4843 loadaddr - Default load address for commands like "bootp", 4844 "rarpboot", "tftpboot", "loadb" or "diskboot" 4845 4846 loads_echo - see CONFIG_LOADS_ECHO 4847 4848 serverip - TFTP server IP address; needed for tftpboot command 4849 4850 bootretry - see CONFIG_BOOT_RETRY_TIME 4851 4852 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4853 4854 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4855 4856 ethprime - controls which interface is used first. 4857 4858 ethact - controls which interface is currently active. 4859 For example you can do the following 4860 4861 => setenv ethact FEC 4862 => ping 192.168.0.1 # traffic sent on FEC 4863 => setenv ethact SCC 4864 => ping 10.0.0.1 # traffic sent on SCC 4865 4866 ethrotate - When set to "no" U-Boot does not go through all 4867 available network interfaces. 4868 It just stays at the currently selected interface. 4869 4870 netretry - When set to "no" each network operation will 4871 either succeed or fail without retrying. 4872 When set to "once" the network operation will 4873 fail when all the available network interfaces 4874 are tried once without success. 4875 Useful on scripts which control the retry operation 4876 themselves. 4877 4878 npe_ucode - set load address for the NPE microcode 4879 4880 silent_linux - If set then Linux will be told to boot silently, by 4881 changing the console to be empty. If "yes" it will be 4882 made silent. If "no" it will not be made silent. If 4883 unset, then it will be made silent if the U-Boot console 4884 is silent. 4885 4886 tftpsrcp - If this is set, the value is used for TFTP's 4887 UDP source port. 4888 4889 tftpdstp - If this is set, the value is used for TFTP's UDP 4890 destination port instead of the Well Know Port 69. 4891 4892 tftpblocksize - Block size to use for TFTP transfers; if not set, 4893 we use the TFTP server's default block size 4894 4895 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4896 seconds, minimum value is 1000 = 1 second). Defines 4897 when a packet is considered to be lost so it has to 4898 be retransmitted. The default is 5000 = 5 seconds. 4899 Lowering this value may make downloads succeed 4900 faster in networks with high packet loss rates or 4901 with unreliable TFTP servers. 4902 4903 tftptimeoutcountmax - maximum count of TFTP timeouts (no 4904 unit, minimum value = 0). Defines how many timeouts 4905 can happen during a single file transfer before that 4906 transfer is aborted. The default is 10, and 0 means 4907 'no timeouts allowed'. Increasing this value may help 4908 downloads succeed with high packet loss rates, or with 4909 unreliable TFTP servers or client hardware. 4910 4911 vlan - When set to a value < 4095 the traffic over 4912 Ethernet is encapsulated/received over 802.1q 4913 VLAN tagged frames. 4914 4915 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 4916 Unsigned value, in milliseconds. If not set, the period will 4917 be either the default (28000), or a value based on 4918 CONFIG_NET_RETRY_COUNT, if defined. This value has 4919 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 4920 4921The following image location variables contain the location of images 4922used in booting. The "Image" column gives the role of the image and is 4923not an environment variable name. The other columns are environment 4924variable names. "File Name" gives the name of the file on a TFTP 4925server, "RAM Address" gives the location in RAM the image will be 4926loaded to, and "Flash Location" gives the image's address in NOR 4927flash or offset in NAND flash. 4928 4929*Note* - these variables don't have to be defined for all boards, some 4930boards currently use other variables for these purposes, and some 4931boards use these variables for other purposes. 4932 4933Image File Name RAM Address Flash Location 4934----- --------- ----------- -------------- 4935u-boot u-boot u-boot_addr_r u-boot_addr 4936Linux kernel bootfile kernel_addr_r kernel_addr 4937device tree blob fdtfile fdt_addr_r fdt_addr 4938ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4939 4940The following environment variables may be used and automatically 4941updated by the network boot commands ("bootp" and "rarpboot"), 4942depending the information provided by your boot server: 4943 4944 bootfile - see above 4945 dnsip - IP address of your Domain Name Server 4946 dnsip2 - IP address of your secondary Domain Name Server 4947 gatewayip - IP address of the Gateway (Router) to use 4948 hostname - Target hostname 4949 ipaddr - see above 4950 netmask - Subnet Mask 4951 rootpath - Pathname of the root filesystem on the NFS server 4952 serverip - see above 4953 4954 4955There are two special Environment Variables: 4956 4957 serial# - contains hardware identification information such 4958 as type string and/or serial number 4959 ethaddr - Ethernet address 4960 4961These variables can be set only once (usually during manufacturing of 4962the board). U-Boot refuses to delete or overwrite these variables 4963once they have been set once. 4964 4965 4966Further special Environment Variables: 4967 4968 ver - Contains the U-Boot version string as printed 4969 with the "version" command. This variable is 4970 readonly (see CONFIG_VERSION_VARIABLE). 4971 4972 4973Please note that changes to some configuration parameters may take 4974only effect after the next boot (yes, that's just like Windoze :-). 4975 4976 4977Callback functions for environment variables: 4978--------------------------------------------- 4979 4980For some environment variables, the behavior of u-boot needs to change 4981when their values are changed. This functionality allows functions to 4982be associated with arbitrary variables. On creation, overwrite, or 4983deletion, the callback will provide the opportunity for some side 4984effect to happen or for the change to be rejected. 4985 4986The callbacks are named and associated with a function using the 4987U_BOOT_ENV_CALLBACK macro in your board or driver code. 4988 4989These callbacks are associated with variables in one of two ways. The 4990static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4991in the board configuration to a string that defines a list of 4992associations. The list must be in the following format: 4993 4994 entry = variable_name[:callback_name] 4995 list = entry[,list] 4996 4997If the callback name is not specified, then the callback is deleted. 4998Spaces are also allowed anywhere in the list. 4999 5000Callbacks can also be associated by defining the ".callbacks" variable 5001with the same list format above. Any association in ".callbacks" will 5002override any association in the static list. You can define 5003CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5004".callbacks" environment variable in the default or embedded environment. 5005 5006If CONFIG_REGEX is defined, the variable_name above is evaluated as a 5007regular expression. This allows multiple variables to be connected to 5008the same callback without explicitly listing them all out. 5009 5010 5011Command Line Parsing: 5012===================== 5013 5014There are two different command line parsers available with U-Boot: 5015the old "simple" one, and the much more powerful "hush" shell: 5016 5017Old, simple command line parser: 5018-------------------------------- 5019 5020- supports environment variables (through setenv / saveenv commands) 5021- several commands on one line, separated by ';' 5022- variable substitution using "... ${name} ..." syntax 5023- special characters ('$', ';') can be escaped by prefixing with '\', 5024 for example: 5025 setenv bootcmd bootm \${address} 5026- You can also escape text by enclosing in single apostrophes, for example: 5027 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5028 5029Hush shell: 5030----------- 5031 5032- similar to Bourne shell, with control structures like 5033 if...then...else...fi, for...do...done; while...do...done, 5034 until...do...done, ... 5035- supports environment ("global") variables (through setenv / saveenv 5036 commands) and local shell variables (through standard shell syntax 5037 "name=value"); only environment variables can be used with "run" 5038 command 5039 5040General rules: 5041-------------- 5042 5043(1) If a command line (or an environment variable executed by a "run" 5044 command) contains several commands separated by semicolon, and 5045 one of these commands fails, then the remaining commands will be 5046 executed anyway. 5047 5048(2) If you execute several variables with one call to run (i. e. 5049 calling run with a list of variables as arguments), any failing 5050 command will cause "run" to terminate, i. e. the remaining 5051 variables are not executed. 5052 5053Note for Redundant Ethernet Interfaces: 5054======================================= 5055 5056Some boards come with redundant Ethernet interfaces; U-Boot supports 5057such configurations and is capable of automatic selection of a 5058"working" interface when needed. MAC assignment works as follows: 5059 5060Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5061MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5062"eth1addr" (=>eth1), "eth2addr", ... 5063 5064If the network interface stores some valid MAC address (for instance 5065in SROM), this is used as default address if there is NO correspon- 5066ding setting in the environment; if the corresponding environment 5067variable is set, this overrides the settings in the card; that means: 5068 5069o If the SROM has a valid MAC address, and there is no address in the 5070 environment, the SROM's address is used. 5071 5072o If there is no valid address in the SROM, and a definition in the 5073 environment exists, then the value from the environment variable is 5074 used. 5075 5076o If both the SROM and the environment contain a MAC address, and 5077 both addresses are the same, this MAC address is used. 5078 5079o If both the SROM and the environment contain a MAC address, and the 5080 addresses differ, the value from the environment is used and a 5081 warning is printed. 5082 5083o If neither SROM nor the environment contain a MAC address, an error 5084 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5085 a random, locally-assigned MAC is used. 5086 5087If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5088will be programmed into hardware as part of the initialization process. This 5089may be skipped by setting the appropriate 'ethmacskip' environment variable. 5090The naming convention is as follows: 5091"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5092 5093Image Formats: 5094============== 5095 5096U-Boot is capable of booting (and performing other auxiliary operations on) 5097images in two formats: 5098 5099New uImage format (FIT) 5100----------------------- 5101 5102Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5103to Flattened Device Tree). It allows the use of images with multiple 5104components (several kernels, ramdisks, etc.), with contents protected by 5105SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5106 5107 5108Old uImage format 5109----------------- 5110 5111Old image format is based on binary files which can be basically anything, 5112preceded by a special header; see the definitions in include/image.h for 5113details; basically, the header defines the following image properties: 5114 5115* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5116 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5117 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5118 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5119 INTEGRITY). 5120* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5121 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5122 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5123* Compression Type (uncompressed, gzip, bzip2) 5124* Load Address 5125* Entry Point 5126* Image Name 5127* Image Timestamp 5128 5129The header is marked by a special Magic Number, and both the header 5130and the data portions of the image are secured against corruption by 5131CRC32 checksums. 5132 5133 5134Linux Support: 5135============== 5136 5137Although U-Boot should support any OS or standalone application 5138easily, the main focus has always been on Linux during the design of 5139U-Boot. 5140 5141U-Boot includes many features that so far have been part of some 5142special "boot loader" code within the Linux kernel. Also, any 5143"initrd" images to be used are no longer part of one big Linux image; 5144instead, kernel and "initrd" are separate images. This implementation 5145serves several purposes: 5146 5147- the same features can be used for other OS or standalone 5148 applications (for instance: using compressed images to reduce the 5149 Flash memory footprint) 5150 5151- it becomes much easier to port new Linux kernel versions because 5152 lots of low-level, hardware dependent stuff are done by U-Boot 5153 5154- the same Linux kernel image can now be used with different "initrd" 5155 images; of course this also means that different kernel images can 5156 be run with the same "initrd". This makes testing easier (you don't 5157 have to build a new "zImage.initrd" Linux image when you just 5158 change a file in your "initrd"). Also, a field-upgrade of the 5159 software is easier now. 5160 5161 5162Linux HOWTO: 5163============ 5164 5165Porting Linux to U-Boot based systems: 5166--------------------------------------- 5167 5168U-Boot cannot save you from doing all the necessary modifications to 5169configure the Linux device drivers for use with your target hardware 5170(no, we don't intend to provide a full virtual machine interface to 5171Linux :-). 5172 5173But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5174 5175Just make sure your machine specific header file (for instance 5176include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5177Information structure as we define in include/asm-<arch>/u-boot.h, 5178and make sure that your definition of IMAP_ADDR uses the same value 5179as your U-Boot configuration in CONFIG_SYS_IMMR. 5180 5181Note that U-Boot now has a driver model, a unified model for drivers. 5182If you are adding a new driver, plumb it into driver model. If there 5183is no uclass available, you are encouraged to create one. See 5184doc/driver-model. 5185 5186 5187Configuring the Linux kernel: 5188----------------------------- 5189 5190No specific requirements for U-Boot. Make sure you have some root 5191device (initial ramdisk, NFS) for your target system. 5192 5193 5194Building a Linux Image: 5195----------------------- 5196 5197With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5198not used. If you use recent kernel source, a new build target 5199"uImage" will exist which automatically builds an image usable by 5200U-Boot. Most older kernels also have support for a "pImage" target, 5201which was introduced for our predecessor project PPCBoot and uses a 5202100% compatible format. 5203 5204Example: 5205 5206 make TQM850L_defconfig 5207 make oldconfig 5208 make dep 5209 make uImage 5210 5211The "uImage" build target uses a special tool (in 'tools/mkimage') to 5212encapsulate a compressed Linux kernel image with header information, 5213CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5214 5215* build a standard "vmlinux" kernel image (in ELF binary format): 5216 5217* convert the kernel into a raw binary image: 5218 5219 ${CROSS_COMPILE}-objcopy -O binary \ 5220 -R .note -R .comment \ 5221 -S vmlinux linux.bin 5222 5223* compress the binary image: 5224 5225 gzip -9 linux.bin 5226 5227* package compressed binary image for U-Boot: 5228 5229 mkimage -A ppc -O linux -T kernel -C gzip \ 5230 -a 0 -e 0 -n "Linux Kernel Image" \ 5231 -d linux.bin.gz uImage 5232 5233 5234The "mkimage" tool can also be used to create ramdisk images for use 5235with U-Boot, either separated from the Linux kernel image, or 5236combined into one file. "mkimage" encapsulates the images with a 64 5237byte header containing information about target architecture, 5238operating system, image type, compression method, entry points, time 5239stamp, CRC32 checksums, etc. 5240 5241"mkimage" can be called in two ways: to verify existing images and 5242print the header information, or to build new images. 5243 5244In the first form (with "-l" option) mkimage lists the information 5245contained in the header of an existing U-Boot image; this includes 5246checksum verification: 5247 5248 tools/mkimage -l image 5249 -l ==> list image header information 5250 5251The second form (with "-d" option) is used to build a U-Boot image 5252from a "data file" which is used as image payload: 5253 5254 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5255 -n name -d data_file image 5256 -A ==> set architecture to 'arch' 5257 -O ==> set operating system to 'os' 5258 -T ==> set image type to 'type' 5259 -C ==> set compression type 'comp' 5260 -a ==> set load address to 'addr' (hex) 5261 -e ==> set entry point to 'ep' (hex) 5262 -n ==> set image name to 'name' 5263 -d ==> use image data from 'datafile' 5264 5265Right now, all Linux kernels for PowerPC systems use the same load 5266address (0x00000000), but the entry point address depends on the 5267kernel version: 5268 5269- 2.2.x kernels have the entry point at 0x0000000C, 5270- 2.3.x and later kernels have the entry point at 0x00000000. 5271 5272So a typical call to build a U-Boot image would read: 5273 5274 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5275 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5276 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5277 > examples/uImage.TQM850L 5278 Image Name: 2.4.4 kernel for TQM850L 5279 Created: Wed Jul 19 02:34:59 2000 5280 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5281 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5282 Load Address: 0x00000000 5283 Entry Point: 0x00000000 5284 5285To verify the contents of the image (or check for corruption): 5286 5287 -> tools/mkimage -l examples/uImage.TQM850L 5288 Image Name: 2.4.4 kernel for TQM850L 5289 Created: Wed Jul 19 02:34:59 2000 5290 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5291 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5292 Load Address: 0x00000000 5293 Entry Point: 0x00000000 5294 5295NOTE: for embedded systems where boot time is critical you can trade 5296speed for memory and install an UNCOMPRESSED image instead: this 5297needs more space in Flash, but boots much faster since it does not 5298need to be uncompressed: 5299 5300 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5301 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5302 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5303 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5304 > examples/uImage.TQM850L-uncompressed 5305 Image Name: 2.4.4 kernel for TQM850L 5306 Created: Wed Jul 19 02:34:59 2000 5307 Image Type: PowerPC Linux Kernel Image (uncompressed) 5308 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5309 Load Address: 0x00000000 5310 Entry Point: 0x00000000 5311 5312 5313Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5314when your kernel is intended to use an initial ramdisk: 5315 5316 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5317 > -A ppc -O linux -T ramdisk -C gzip \ 5318 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5319 Image Name: Simple Ramdisk Image 5320 Created: Wed Jan 12 14:01:50 2000 5321 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5322 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5323 Load Address: 0x00000000 5324 Entry Point: 0x00000000 5325 5326The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5327option performs the converse operation of the mkimage's second form (the "-d" 5328option). Given an image built by mkimage, the dumpimage extracts a "data file" 5329from the image: 5330 5331 tools/dumpimage -i image -T type -p position data_file 5332 -i ==> extract from the 'image' a specific 'data_file' 5333 -T ==> set image type to 'type' 5334 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5335 5336 5337Installing a Linux Image: 5338------------------------- 5339 5340To downloading a U-Boot image over the serial (console) interface, 5341you must convert the image to S-Record format: 5342 5343 objcopy -I binary -O srec examples/image examples/image.srec 5344 5345The 'objcopy' does not understand the information in the U-Boot 5346image header, so the resulting S-Record file will be relative to 5347address 0x00000000. To load it to a given address, you need to 5348specify the target address as 'offset' parameter with the 'loads' 5349command. 5350 5351Example: install the image to address 0x40100000 (which on the 5352TQM8xxL is in the first Flash bank): 5353 5354 => erase 40100000 401FFFFF 5355 5356 .......... done 5357 Erased 8 sectors 5358 5359 => loads 40100000 5360 ## Ready for S-Record download ... 5361 ~>examples/image.srec 5362 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5363 ... 5364 15989 15990 15991 15992 5365 [file transfer complete] 5366 [connected] 5367 ## Start Addr = 0x00000000 5368 5369 5370You can check the success of the download using the 'iminfo' command; 5371this includes a checksum verification so you can be sure no data 5372corruption happened: 5373 5374 => imi 40100000 5375 5376 ## Checking Image at 40100000 ... 5377 Image Name: 2.2.13 for initrd on TQM850L 5378 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5379 Data Size: 335725 Bytes = 327 kB = 0 MB 5380 Load Address: 00000000 5381 Entry Point: 0000000c 5382 Verifying Checksum ... OK 5383 5384 5385Boot Linux: 5386----------- 5387 5388The "bootm" command is used to boot an application that is stored in 5389memory (RAM or Flash). In case of a Linux kernel image, the contents 5390of the "bootargs" environment variable is passed to the kernel as 5391parameters. You can check and modify this variable using the 5392"printenv" and "setenv" commands: 5393 5394 5395 => printenv bootargs 5396 bootargs=root=/dev/ram 5397 5398 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5399 5400 => printenv bootargs 5401 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5402 5403 => bootm 40020000 5404 ## Booting Linux kernel at 40020000 ... 5405 Image Name: 2.2.13 for NFS on TQM850L 5406 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5407 Data Size: 381681 Bytes = 372 kB = 0 MB 5408 Load Address: 00000000 5409 Entry Point: 0000000c 5410 Verifying Checksum ... OK 5411 Uncompressing Kernel Image ... OK 5412 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 5413 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5414 time_init: decrementer frequency = 187500000/60 5415 Calibrating delay loop... 49.77 BogoMIPS 5416 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5417 ... 5418 5419If you want to boot a Linux kernel with initial RAM disk, you pass 5420the memory addresses of both the kernel and the initrd image (PPBCOOT 5421format!) to the "bootm" command: 5422 5423 => imi 40100000 40200000 5424 5425 ## Checking Image at 40100000 ... 5426 Image Name: 2.2.13 for initrd on TQM850L 5427 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5428 Data Size: 335725 Bytes = 327 kB = 0 MB 5429 Load Address: 00000000 5430 Entry Point: 0000000c 5431 Verifying Checksum ... OK 5432 5433 ## Checking Image at 40200000 ... 5434 Image Name: Simple Ramdisk Image 5435 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5436 Data Size: 566530 Bytes = 553 kB = 0 MB 5437 Load Address: 00000000 5438 Entry Point: 00000000 5439 Verifying Checksum ... OK 5440 5441 => bootm 40100000 40200000 5442 ## Booting Linux kernel at 40100000 ... 5443 Image Name: 2.2.13 for initrd on TQM850L 5444 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5445 Data Size: 335725 Bytes = 327 kB = 0 MB 5446 Load Address: 00000000 5447 Entry Point: 0000000c 5448 Verifying Checksum ... OK 5449 Uncompressing Kernel Image ... OK 5450 ## Loading RAMDisk Image at 40200000 ... 5451 Image Name: Simple Ramdisk Image 5452 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5453 Data Size: 566530 Bytes = 553 kB = 0 MB 5454 Load Address: 00000000 5455 Entry Point: 00000000 5456 Verifying Checksum ... OK 5457 Loading Ramdisk ... OK 5458 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 5459 Boot arguments: root=/dev/ram 5460 time_init: decrementer frequency = 187500000/60 5461 Calibrating delay loop... 49.77 BogoMIPS 5462 ... 5463 RAMDISK: Compressed image found at block 0 5464 VFS: Mounted root (ext2 filesystem). 5465 5466 bash# 5467 5468Boot Linux and pass a flat device tree: 5469----------- 5470 5471First, U-Boot must be compiled with the appropriate defines. See the section 5472titled "Linux Kernel Interface" above for a more in depth explanation. The 5473following is an example of how to start a kernel and pass an updated 5474flat device tree: 5475 5476=> print oftaddr 5477oftaddr=0x300000 5478=> print oft 5479oft=oftrees/mpc8540ads.dtb 5480=> tftp $oftaddr $oft 5481Speed: 1000, full duplex 5482Using TSEC0 device 5483TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5484Filename 'oftrees/mpc8540ads.dtb'. 5485Load address: 0x300000 5486Loading: # 5487done 5488Bytes transferred = 4106 (100a hex) 5489=> tftp $loadaddr $bootfile 5490Speed: 1000, full duplex 5491Using TSEC0 device 5492TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5493Filename 'uImage'. 5494Load address: 0x200000 5495Loading:############ 5496done 5497Bytes transferred = 1029407 (fb51f hex) 5498=> print loadaddr 5499loadaddr=200000 5500=> print oftaddr 5501oftaddr=0x300000 5502=> bootm $loadaddr - $oftaddr 5503## Booting image at 00200000 ... 5504 Image Name: Linux-2.6.17-dirty 5505 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5506 Data Size: 1029343 Bytes = 1005.2 kB 5507 Load Address: 00000000 5508 Entry Point: 00000000 5509 Verifying Checksum ... OK 5510 Uncompressing Kernel Image ... OK 5511Booting using flat device tree at 0x300000 5512Using MPC85xx ADS machine description 5513Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5514[snip] 5515 5516 5517More About U-Boot Image Types: 5518------------------------------ 5519 5520U-Boot supports the following image types: 5521 5522 "Standalone Programs" are directly runnable in the environment 5523 provided by U-Boot; it is expected that (if they behave 5524 well) you can continue to work in U-Boot after return from 5525 the Standalone Program. 5526 "OS Kernel Images" are usually images of some Embedded OS which 5527 will take over control completely. Usually these programs 5528 will install their own set of exception handlers, device 5529 drivers, set up the MMU, etc. - this means, that you cannot 5530 expect to re-enter U-Boot except by resetting the CPU. 5531 "RAMDisk Images" are more or less just data blocks, and their 5532 parameters (address, size) are passed to an OS kernel that is 5533 being started. 5534 "Multi-File Images" contain several images, typically an OS 5535 (Linux) kernel image and one or more data images like 5536 RAMDisks. This construct is useful for instance when you want 5537 to boot over the network using BOOTP etc., where the boot 5538 server provides just a single image file, but you want to get 5539 for instance an OS kernel and a RAMDisk image. 5540 5541 "Multi-File Images" start with a list of image sizes, each 5542 image size (in bytes) specified by an "uint32_t" in network 5543 byte order. This list is terminated by an "(uint32_t)0". 5544 Immediately after the terminating 0 follow the images, one by 5545 one, all aligned on "uint32_t" boundaries (size rounded up to 5546 a multiple of 4 bytes). 5547 5548 "Firmware Images" are binary images containing firmware (like 5549 U-Boot or FPGA images) which usually will be programmed to 5550 flash memory. 5551 5552 "Script files" are command sequences that will be executed by 5553 U-Boot's command interpreter; this feature is especially 5554 useful when you configure U-Boot to use a real shell (hush) 5555 as command interpreter. 5556 5557Booting the Linux zImage: 5558------------------------- 5559 5560On some platforms, it's possible to boot Linux zImage. This is done 5561using the "bootz" command. The syntax of "bootz" command is the same 5562as the syntax of "bootm" command. 5563 5564Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5565kernel with raw initrd images. The syntax is slightly different, the 5566address of the initrd must be augmented by it's size, in the following 5567format: "<initrd addres>:<initrd size>". 5568 5569 5570Standalone HOWTO: 5571================= 5572 5573One of the features of U-Boot is that you can dynamically load and 5574run "standalone" applications, which can use some resources of 5575U-Boot like console I/O functions or interrupt services. 5576 5577Two simple examples are included with the sources: 5578 5579"Hello World" Demo: 5580------------------- 5581 5582'examples/hello_world.c' contains a small "Hello World" Demo 5583application; it is automatically compiled when you build U-Boot. 5584It's configured to run at address 0x00040004, so you can play with it 5585like that: 5586 5587 => loads 5588 ## Ready for S-Record download ... 5589 ~>examples/hello_world.srec 5590 1 2 3 4 5 6 7 8 9 10 11 ... 5591 [file transfer complete] 5592 [connected] 5593 ## Start Addr = 0x00040004 5594 5595 => go 40004 Hello World! This is a test. 5596 ## Starting application at 0x00040004 ... 5597 Hello World 5598 argc = 7 5599 argv[0] = "40004" 5600 argv[1] = "Hello" 5601 argv[2] = "World!" 5602 argv[3] = "This" 5603 argv[4] = "is" 5604 argv[5] = "a" 5605 argv[6] = "test." 5606 argv[7] = "<NULL>" 5607 Hit any key to exit ... 5608 5609 ## Application terminated, rc = 0x0 5610 5611Another example, which demonstrates how to register a CPM interrupt 5612handler with the U-Boot code, can be found in 'examples/timer.c'. 5613Here, a CPM timer is set up to generate an interrupt every second. 5614The interrupt service routine is trivial, just printing a '.' 5615character, but this is just a demo program. The application can be 5616controlled by the following keys: 5617 5618 ? - print current values og the CPM Timer registers 5619 b - enable interrupts and start timer 5620 e - stop timer and disable interrupts 5621 q - quit application 5622 5623 => loads 5624 ## Ready for S-Record download ... 5625 ~>examples/timer.srec 5626 1 2 3 4 5 6 7 8 9 10 11 ... 5627 [file transfer complete] 5628 [connected] 5629 ## Start Addr = 0x00040004 5630 5631 => go 40004 5632 ## Starting application at 0x00040004 ... 5633 TIMERS=0xfff00980 5634 Using timer 1 5635 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5636 5637Hit 'b': 5638 [q, b, e, ?] Set interval 1000000 us 5639 Enabling timer 5640Hit '?': 5641 [q, b, e, ?] ........ 5642 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5643Hit '?': 5644 [q, b, e, ?] . 5645 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5646Hit '?': 5647 [q, b, e, ?] . 5648 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5649Hit '?': 5650 [q, b, e, ?] . 5651 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5652Hit 'e': 5653 [q, b, e, ?] ...Stopping timer 5654Hit 'q': 5655 [q, b, e, ?] ## Application terminated, rc = 0x0 5656 5657 5658Minicom warning: 5659================ 5660 5661Over time, many people have reported problems when trying to use the 5662"minicom" terminal emulation program for serial download. I (wd) 5663consider minicom to be broken, and recommend not to use it. Under 5664Unix, I recommend to use C-Kermit for general purpose use (and 5665especially for kermit binary protocol download ("loadb" command), and 5666use "cu" for S-Record download ("loads" command). See 5667http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5668for help with kermit. 5669 5670 5671Nevertheless, if you absolutely want to use it try adding this 5672configuration to your "File transfer protocols" section: 5673 5674 Name Program Name U/D FullScr IO-Red. Multi 5675 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5676 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5677 5678 5679NetBSD Notes: 5680============= 5681 5682Starting at version 0.9.2, U-Boot supports NetBSD both as host 5683(build U-Boot) and target system (boots NetBSD/mpc8xx). 5684 5685Building requires a cross environment; it is known to work on 5686NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5687need gmake since the Makefiles are not compatible with BSD make). 5688Note that the cross-powerpc package does not install include files; 5689attempting to build U-Boot will fail because <machine/ansi.h> is 5690missing. This file has to be installed and patched manually: 5691 5692 # cd /usr/pkg/cross/powerpc-netbsd/include 5693 # mkdir powerpc 5694 # ln -s powerpc machine 5695 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5696 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5697 5698Native builds *don't* work due to incompatibilities between native 5699and U-Boot include files. 5700 5701Booting assumes that (the first part of) the image booted is a 5702stage-2 loader which in turn loads and then invokes the kernel 5703proper. Loader sources will eventually appear in the NetBSD source 5704tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5705meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5706 5707 5708Implementation Internals: 5709========================= 5710 5711The following is not intended to be a complete description of every 5712implementation detail. However, it should help to understand the 5713inner workings of U-Boot and make it easier to port it to custom 5714hardware. 5715 5716 5717Initial Stack, Global Data: 5718--------------------------- 5719 5720The implementation of U-Boot is complicated by the fact that U-Boot 5721starts running out of ROM (flash memory), usually without access to 5722system RAM (because the memory controller is not initialized yet). 5723This means that we don't have writable Data or BSS segments, and BSS 5724is not initialized as zero. To be able to get a C environment working 5725at all, we have to allocate at least a minimal stack. Implementation 5726options for this are defined and restricted by the CPU used: Some CPU 5727models provide on-chip memory (like the IMMR area on MPC8xx and 5728MPC826x processors), on others (parts of) the data cache can be 5729locked as (mis-) used as memory, etc. 5730 5731 Chris Hallinan posted a good summary of these issues to the 5732 U-Boot mailing list: 5733 5734 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5735 From: "Chris Hallinan" <clh@net1plus.com> 5736 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5737 ... 5738 5739 Correct me if I'm wrong, folks, but the way I understand it 5740 is this: Using DCACHE as initial RAM for Stack, etc, does not 5741 require any physical RAM backing up the cache. The cleverness 5742 is that the cache is being used as a temporary supply of 5743 necessary storage before the SDRAM controller is setup. It's 5744 beyond the scope of this list to explain the details, but you 5745 can see how this works by studying the cache architecture and 5746 operation in the architecture and processor-specific manuals. 5747 5748 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5749 is another option for the system designer to use as an 5750 initial stack/RAM area prior to SDRAM being available. Either 5751 option should work for you. Using CS 4 should be fine if your 5752 board designers haven't used it for something that would 5753 cause you grief during the initial boot! It is frequently not 5754 used. 5755 5756 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5757 with your processor/board/system design. The default value 5758 you will find in any recent u-boot distribution in 5759 walnut.h should work for you. I'd set it to a value larger 5760 than your SDRAM module. If you have a 64MB SDRAM module, set 5761 it above 400_0000. Just make sure your board has no resources 5762 that are supposed to respond to that address! That code in 5763 start.S has been around a while and should work as is when 5764 you get the config right. 5765 5766 -Chris Hallinan 5767 DS4.COM, Inc. 5768 5769It is essential to remember this, since it has some impact on the C 5770code for the initialization procedures: 5771 5772* Initialized global data (data segment) is read-only. Do not attempt 5773 to write it. 5774 5775* Do not use any uninitialized global data (or implicitly initialized 5776 as zero data - BSS segment) at all - this is undefined, initiali- 5777 zation is performed later (when relocating to RAM). 5778 5779* Stack space is very limited. Avoid big data buffers or things like 5780 that. 5781 5782Having only the stack as writable memory limits means we cannot use 5783normal global data to share information between the code. But it 5784turned out that the implementation of U-Boot can be greatly 5785simplified by making a global data structure (gd_t) available to all 5786functions. We could pass a pointer to this data as argument to _all_ 5787functions, but this would bloat the code. Instead we use a feature of 5788the GCC compiler (Global Register Variables) to share the data: we 5789place a pointer (gd) to the global data into a register which we 5790reserve for this purpose. 5791 5792When choosing a register for such a purpose we are restricted by the 5793relevant (E)ABI specifications for the current architecture, and by 5794GCC's implementation. 5795 5796For PowerPC, the following registers have specific use: 5797 R1: stack pointer 5798 R2: reserved for system use 5799 R3-R4: parameter passing and return values 5800 R5-R10: parameter passing 5801 R13: small data area pointer 5802 R30: GOT pointer 5803 R31: frame pointer 5804 5805 (U-Boot also uses R12 as internal GOT pointer. r12 5806 is a volatile register so r12 needs to be reset when 5807 going back and forth between asm and C) 5808 5809 ==> U-Boot will use R2 to hold a pointer to the global data 5810 5811 Note: on PPC, we could use a static initializer (since the 5812 address of the global data structure is known at compile time), 5813 but it turned out that reserving a register results in somewhat 5814 smaller code - although the code savings are not that big (on 5815 average for all boards 752 bytes for the whole U-Boot image, 5816 624 text + 127 data). 5817 5818On ARM, the following registers are used: 5819 5820 R0: function argument word/integer result 5821 R1-R3: function argument word 5822 R9: platform specific 5823 R10: stack limit (used only if stack checking is enabled) 5824 R11: argument (frame) pointer 5825 R12: temporary workspace 5826 R13: stack pointer 5827 R14: link register 5828 R15: program counter 5829 5830 ==> U-Boot will use R9 to hold a pointer to the global data 5831 5832 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5833 5834On Nios II, the ABI is documented here: 5835 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5836 5837 ==> U-Boot will use gp to hold a pointer to the global data 5838 5839 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5840 to access small data sections, so gp is free. 5841 5842On NDS32, the following registers are used: 5843 5844 R0-R1: argument/return 5845 R2-R5: argument 5846 R15: temporary register for assembler 5847 R16: trampoline register 5848 R28: frame pointer (FP) 5849 R29: global pointer (GP) 5850 R30: link register (LP) 5851 R31: stack pointer (SP) 5852 PC: program counter (PC) 5853 5854 ==> U-Boot will use R10 to hold a pointer to the global data 5855 5856NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5857or current versions of GCC may "optimize" the code too much. 5858 5859Memory Management: 5860------------------ 5861 5862U-Boot runs in system state and uses physical addresses, i.e. the 5863MMU is not used either for address mapping nor for memory protection. 5864 5865The available memory is mapped to fixed addresses using the memory 5866controller. In this process, a contiguous block is formed for each 5867memory type (Flash, SDRAM, SRAM), even when it consists of several 5868physical memory banks. 5869 5870U-Boot is installed in the first 128 kB of the first Flash bank (on 5871TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5872booting and sizing and initializing DRAM, the code relocates itself 5873to the upper end of DRAM. Immediately below the U-Boot code some 5874memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5875configuration setting]. Below that, a structure with global Board 5876Info data is placed, followed by the stack (growing downward). 5877 5878Additionally, some exception handler code is copied to the low 8 kB 5879of DRAM (0x00000000 ... 0x00001FFF). 5880 5881So a typical memory configuration with 16 MB of DRAM could look like 5882this: 5883 5884 0x0000 0000 Exception Vector code 5885 : 5886 0x0000 1FFF 5887 0x0000 2000 Free for Application Use 5888 : 5889 : 5890 5891 : 5892 : 5893 0x00FB FF20 Monitor Stack (Growing downward) 5894 0x00FB FFAC Board Info Data and permanent copy of global data 5895 0x00FC 0000 Malloc Arena 5896 : 5897 0x00FD FFFF 5898 0x00FE 0000 RAM Copy of Monitor Code 5899 ... eventually: LCD or video framebuffer 5900 ... eventually: pRAM (Protected RAM - unchanged by reset) 5901 0x00FF FFFF [End of RAM] 5902 5903 5904System Initialization: 5905---------------------- 5906 5907In the reset configuration, U-Boot starts at the reset entry point 5908(on most PowerPC systems at address 0x00000100). Because of the reset 5909configuration for CS0# this is a mirror of the on board Flash memory. 5910To be able to re-map memory U-Boot then jumps to its link address. 5911To be able to implement the initialization code in C, a (small!) 5912initial stack is set up in the internal Dual Ported RAM (in case CPUs 5913which provide such a feature like MPC8xx or MPC8260), or in a locked 5914part of the data cache. After that, U-Boot initializes the CPU core, 5915the caches and the SIU. 5916 5917Next, all (potentially) available memory banks are mapped using a 5918preliminary mapping. For example, we put them on 512 MB boundaries 5919(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5920on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5921programmed for SDRAM access. Using the temporary configuration, a 5922simple memory test is run that determines the size of the SDRAM 5923banks. 5924 5925When there is more than one SDRAM bank, and the banks are of 5926different size, the largest is mapped first. For equal size, the first 5927bank (CS2#) is mapped first. The first mapping is always for address 59280x00000000, with any additional banks following immediately to create 5929contiguous memory starting from 0. 5930 5931Then, the monitor installs itself at the upper end of the SDRAM area 5932and allocates memory for use by malloc() and for the global Board 5933Info data; also, the exception vector code is copied to the low RAM 5934pages, and the final stack is set up. 5935 5936Only after this relocation will you have a "normal" C environment; 5937until that you are restricted in several ways, mostly because you are 5938running from ROM, and because the code will have to be relocated to a 5939new address in RAM. 5940 5941 5942U-Boot Porting Guide: 5943---------------------- 5944 5945[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5946list, October 2002] 5947 5948 5949int main(int argc, char *argv[]) 5950{ 5951 sighandler_t no_more_time; 5952 5953 signal(SIGALRM, no_more_time); 5954 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5955 5956 if (available_money > available_manpower) { 5957 Pay consultant to port U-Boot; 5958 return 0; 5959 } 5960 5961 Download latest U-Boot source; 5962 5963 Subscribe to u-boot mailing list; 5964 5965 if (clueless) 5966 email("Hi, I am new to U-Boot, how do I get started?"); 5967 5968 while (learning) { 5969 Read the README file in the top level directory; 5970 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5971 Read applicable doc/*.README; 5972 Read the source, Luke; 5973 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5974 } 5975 5976 if (available_money > toLocalCurrency ($2500)) 5977 Buy a BDI3000; 5978 else 5979 Add a lot of aggravation and time; 5980 5981 if (a similar board exists) { /* hopefully... */ 5982 cp -a board/<similar> board/<myboard> 5983 cp include/configs/<similar>.h include/configs/<myboard>.h 5984 } else { 5985 Create your own board support subdirectory; 5986 Create your own board include/configs/<myboard>.h file; 5987 } 5988 Edit new board/<myboard> files 5989 Edit new include/configs/<myboard>.h 5990 5991 while (!accepted) { 5992 while (!running) { 5993 do { 5994 Add / modify source code; 5995 } until (compiles); 5996 Debug; 5997 if (clueless) 5998 email("Hi, I am having problems..."); 5999 } 6000 Send patch file to the U-Boot email list; 6001 if (reasonable critiques) 6002 Incorporate improvements from email list code review; 6003 else 6004 Defend code as written; 6005 } 6006 6007 return 0; 6008} 6009 6010void no_more_time (int sig) 6011{ 6012 hire_a_guru(); 6013} 6014 6015 6016Coding Standards: 6017----------------- 6018 6019All contributions to U-Boot should conform to the Linux kernel 6020coding style; see the file "Documentation/CodingStyle" and the script 6021"scripts/Lindent" in your Linux kernel source directory. 6022 6023Source files originating from a different project (for example the 6024MTD subsystem) are generally exempt from these guidelines and are not 6025reformatted to ease subsequent migration to newer versions of those 6026sources. 6027 6028Please note that U-Boot is implemented in C (and to some small parts in 6029Assembler); no C++ is used, so please do not use C++ style comments (//) 6030in your code. 6031 6032Please also stick to the following formatting rules: 6033- remove any trailing white space 6034- use TAB characters for indentation and vertical alignment, not spaces 6035- make sure NOT to use DOS '\r\n' line feeds 6036- do not add more than 2 consecutive empty lines to source files 6037- do not add trailing empty lines to source files 6038 6039Submissions which do not conform to the standards may be returned 6040with a request to reformat the changes. 6041 6042 6043Submitting Patches: 6044------------------- 6045 6046Since the number of patches for U-Boot is growing, we need to 6047establish some rules. Submissions which do not conform to these rules 6048may be rejected, even when they contain important and valuable stuff. 6049 6050Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6051 6052Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6053see http://lists.denx.de/mailman/listinfo/u-boot 6054 6055When you send a patch, please include the following information with 6056it: 6057 6058* For bug fixes: a description of the bug and how your patch fixes 6059 this bug. Please try to include a way of demonstrating that the 6060 patch actually fixes something. 6061 6062* For new features: a description of the feature and your 6063 implementation. 6064 6065* A CHANGELOG entry as plaintext (separate from the patch) 6066 6067* For major contributions, add a MAINTAINERS file with your 6068 information and associated file and directory references. 6069 6070* When you add support for a new board, don't forget to add a 6071 maintainer e-mail address to the boards.cfg file, too. 6072 6073* If your patch adds new configuration options, don't forget to 6074 document these in the README file. 6075 6076* The patch itself. If you are using git (which is *strongly* 6077 recommended) you can easily generate the patch using the 6078 "git format-patch". If you then use "git send-email" to send it to 6079 the U-Boot mailing list, you will avoid most of the common problems 6080 with some other mail clients. 6081 6082 If you cannot use git, use "diff -purN OLD NEW". If your version of 6083 diff does not support these options, then get the latest version of 6084 GNU diff. 6085 6086 The current directory when running this command shall be the parent 6087 directory of the U-Boot source tree (i. e. please make sure that 6088 your patch includes sufficient directory information for the 6089 affected files). 6090 6091 We prefer patches as plain text. MIME attachments are discouraged, 6092 and compressed attachments must not be used. 6093 6094* If one logical set of modifications affects or creates several 6095 files, all these changes shall be submitted in a SINGLE patch file. 6096 6097* Changesets that contain different, unrelated modifications shall be 6098 submitted as SEPARATE patches, one patch per changeset. 6099 6100 6101Notes: 6102 6103* Before sending the patch, run the buildman script on your patched 6104 source tree and make sure that no errors or warnings are reported 6105 for any of the boards. 6106 6107* Keep your modifications to the necessary minimum: A patch 6108 containing several unrelated changes or arbitrary reformats will be 6109 returned with a request to re-formatting / split it. 6110 6111* If you modify existing code, make sure that your new code does not 6112 add to the memory footprint of the code ;-) Small is beautiful! 6113 When adding new features, these should compile conditionally only 6114 (using #ifdef), and the resulting code with the new feature 6115 disabled must not need more memory than the old code without your 6116 modification. 6117 6118* Remember that there is a size limit of 100 kB per message on the 6119 u-boot mailing list. Bigger patches will be moderated. If they are 6120 reasonable and not too big, they will be acknowledged. But patches 6121 bigger than the size limit should be avoided. 6122