diff options
Diffstat (limited to 'README')
| -rw-r--r-- | README | 271 |
1 files changed, 6 insertions, 265 deletions
@@ -45,17 +45,17 @@ Where to get help: In case you have questions about, problems with or contributions for U-Boot, you should send a message to the U-Boot mailing list at -<[email protected]>. There is also an archive of previous traffic +<[email protected]>. There is also an archive of previous traffic on the mailing list - please search the archive before asking FAQ's. -Please see https://lists.denx.de/pipermail/u-boot and +Please see https://lists.u-boot-project.org/pipermail/u-boot and https://marc.info/?l=u-boot Where to get source code: ========================= The U-Boot source code is maintained in the Git repository at -https://source.denx.de/u-boot/u-boot.git ; you can browse it online at -https://source.denx.de/u-boot/u-boot +https://git.u-boot-project.org/u-boot/u-boot.git ; you can browse it online at +https://git.u-boot-project.org/u-boot/u-boot The "Tags" links on this page allow you to download tarballs of any version you might be interested in. Official releases are also @@ -628,98 +628,6 @@ The following options need to be configured: If you do not have i2c muxes on your board, omit this define. -- Legacy I2C Support: - If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) - then the following macros need to be defined (examples are - from include/configs/lwmon.h): - - I2C_INIT - - (Optional). Any commands necessary to enable the I2C - controller or configure ports. - - eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) - - I2C_ACTIVE - - The code necessary to make the I2C data line active - (driven). If the data line is open collector, this - define can be null. - - eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) - - I2C_TRISTATE - - The code necessary to make the I2C data line tri-stated - (inactive). If the data line is open collector, this - define can be null. - - eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) - - I2C_READ - - Code that returns true if the I2C data line is high, - false if it is low. - - eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) - - I2C_SDA(bit) - - If <bit> is true, sets the I2C data line high. If it - is false, it clears it (low). - - eg: #define I2C_SDA(bit) \ - if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ - else immr->im_cpm.cp_pbdat &= ~PB_SDA - - I2C_SCL(bit) - - If <bit> is true, sets the I2C clock line high. If it - is false, it clears it (low). - - eg: #define I2C_SCL(bit) \ - if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ - else immr->im_cpm.cp_pbdat &= ~PB_SCL - - I2C_DELAY - - This delay is invoked four times per clock cycle so this - controls the rate of data transfer. The data rate thus - is 1 / (I2C_DELAY * 4). Often defined to be something - like: - - #define I2C_DELAY udelay(2) - - CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA - - If your arch supports the generic GPIO framework (asm/gpio.h), - then you may alternatively define the two GPIOs that are to be - used as SCL / SDA. Any of the previous I2C_xxx macros will - have GPIO-based defaults assigned to them as appropriate. - - You should define these to the GPIO value as given directly to - the generic GPIO functions. - - CFG_SYS_I2C_NOPROBES - - This option specifies a list of I2C devices that will be skipped - when the 'i2c probe' command is issued. - - e.g. - #define CFG_SYS_I2C_NOPROBES {0x50,0x68} - - will skip addresses 0x50 and 0x68 on a board with one I2C bus - - CONFIG_SOFT_I2C_READ_REPEATED_START - - defining this will force the i2c_read() function in - the soft_i2c driver to perform an I2C repeated start - between writing the address pointer and reading the - data. If this define is omitted the default behaviour - of doing a stop-start sequence will be used. Most I2C - devices can use either method, but some require one or - the other. - - SPI Support: CONFIG_SPI Enables SPI driver (so far only tested with @@ -799,7 +707,7 @@ The following options need to be configured: The same can be accomplished in a more flexible way for any variable by configuring the type of access to allow for those variables in the ".flags" variable - or define CFG_ENV_FLAGS_LIST_STATIC. + or by setting CONFIG_ENV_FLAGS_LIST_STATIC. - Protected RAM: CFG_PRAM @@ -1033,173 +941,6 @@ typically in board_init_f() and board_init_r(). - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() - CONFIG_BOARD_LATE_INIT: Call board_late_init() -Configuration Settings: ------------------------ - -- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; - undefine this when you're short of memory. - -- CFG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default - width of the commands listed in the 'help' command output. - -- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to - prompt for user input. - -- CFG_SYS_BAUDRATE_TABLE: - List of legal baudrate settings for this board. - -- CFG_SYS_MEM_RESERVE_SECURE - Only implemented for ARMv8 for now. - If defined, the size of CFG_SYS_MEM_RESERVE_SECURE memory - is substracted from total RAM and won't be reported to OS. - This memory can be used as secure memory. A variable - gd->arch.secure_ram is used to track the location. In systems - the RAM base is not zero, or RAM is divided into banks, - this variable needs to be recalcuated to get the address. - -- CFG_SYS_SDRAM_BASE: - Physical start address of SDRAM. _Must_ be 0 here. - -- CFG_SYS_FLASH_BASE: - Physical start address of Flash memory. - -- CONFIG_SYS_MALLOC_LEN: - Size of DRAM reserved for malloc() use. - -- CFG_SYS_BOOTMAPSZ: - Maximum size of memory mapped by the startup code of - the Linux kernel; all data that must be processed by - the Linux kernel (bd_info, boot arguments, FDT blob if - used) must be put below this limit, unless "bootm_low" - environment variable is defined and non-zero. In such case - all data for the Linux kernel must be between "bootm_low" - and "bootm_low" + CFG_SYS_BOOTMAPSZ. The environment - variable "bootm_mapsize" will override the value of - CFG_SYS_BOOTMAPSZ. If CFG_SYS_BOOTMAPSZ is undefined, - then the value in "bootm_size" will be used instead. - -- CONFIG_SYS_BOOT_GET_CMDLINE: - Enables allocating and saving kernel cmdline in space between - "bootm_low" and "bootm_low" + BOOTMAPSZ. - -- CONFIG_SYS_BOOT_GET_KBD: - Enables allocating and saving a kernel copy of the bd_info in - space between "bootm_low" and "bootm_low" + BOOTMAPSZ. - -- CONFIG_SYS_FLASH_PROTECTION - If defined, hardware flash sectors protection is used - instead of U-Boot software protection. - -- CONFIG_SYS_FLASH_CFI: - Define if the flash driver uses extra elements in the - common flash structure for storing flash geometry. - -- CONFIG_FLASH_CFI_DRIVER - This option also enables the building of the cfi_flash driver - in the drivers directory - -- CONFIG_FLASH_CFI_MTD - This option enables the building of the cfi_mtd driver - in the drivers directory. The driver exports CFI flash - to the MTD layer. - -- CONFIG_SYS_FLASH_USE_BUFFER_WRITE - Use buffered writes to flash. - -- CONFIG_ENV_FLAGS_LIST_DEFAULT -- CFG_ENV_FLAGS_LIST_STATIC - Enable validation of the values given to environment variables when - calling env set. Variables can be restricted to only decimal, - hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, - the variables can also be restricted to IP address or MAC address. - - The format of the list is: - type_attribute = [s|d|x|b|i|m] - access_attribute = [a|r|o|c] - attributes = type_attribute[access_attribute] - entry = variable_name[:attributes] - list = entry[,list] - - The type attributes are: - s - String (default) - d - Decimal - x - Hexadecimal - b - Boolean ([1yYtT|0nNfF]) - i - IP address - m - MAC address - - The access attributes are: - a - Any (default) - r - Read-only - o - Write-once - c - Change-default - - - CONFIG_ENV_FLAGS_LIST_DEFAULT - Define this to a list (string) to define the ".flags" - environment variable in the default or embedded environment. - - - CFG_ENV_FLAGS_LIST_STATIC - Define this to a list (string) to define validation that - should be done if an entry is not found in the ".flags" - environment variable. To override a setting in the static - list, simply add an entry for the same variable name to the - ".flags" variable. - - If CONFIG_REGEX is defined, the variable_name above is evaluated as a - regular expression. This allows multiple variables to define the same - flags without explicitly listing them for each variable. - -The following definitions that deal with the placement and management -of environment data (variable area); in general, we support the -following configurations: - -BE CAREFUL! The first access to the environment happens quite early -in U-Boot initialization (when we try to get the setting of for the -console baudrate). You *MUST* have mapped your NVRAM area then, or -U-Boot will hang. - -Please note that even with NVRAM we still use a copy of the -environment in RAM: we could work on NVRAM directly, but we want to -keep settings there always unmodified except somebody uses "saveenv" -to save the current settings. - -BE CAREFUL! For some special cases, the local device can not use -"saveenv" command. For example, the local device will get the -environment stored in a remote NOR flash by SRIO or PCIE link, -but it can not erase, write this NOR flash by SRIO or PCIE interface. - -- CONFIG_NAND_ENV_DST - - Defines address in RAM to which the nand_spl code should copy the - environment. If redundant environment is used, it will be copied to - CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. - -Please note that the environment is read-only until the monitor -has been relocated to RAM and a RAM copy of the environment has been -created; also, when using EEPROM you will have to use env_get_f() -until then to read environment variables. - -The environment is protected by a CRC32 checksum. Before the monitor -is relocated into RAM, as a result of a bad CRC you will be working -with the compiled-in default environment - *silently*!!! [This is -necessary, because the first environment variable we need is the -"baudrate" setting for the console - if we have a bad CRC, we don't -have any device yet where we could complain.] - -Note: once the monitor has been relocated, then it will complain if -the default environment is used; a new CRC is computed as soon as you -use the "saveenv" command to store a valid environment. - -- CONFIG_DISPLAY_BOARDINFO - Display information about the board that U-Boot is running on - when U-Boot starts up. The board function checkboard() is called - to do this. - -- CONFIG_DISPLAY_BOARDINFO_LATE - Similar to the previous option, but display this information - later, once stdio is running and output goes to the LCD, if - present. - Low Level (hardware related) configuration options: --------------------------------------------------- @@ -2373,5 +2114,5 @@ Contributing The U-Boot projects depends on contributions from the user community. If you want to participate, please, have a look at the 'General' -section of https://docs.u-boot.org/en/latest/develop/index.html +section of https://docs.u-boot-project.org/en/latest/develop/index.html where we describe coding standards and the patch submission process. |