different from COUNTER_FREQUENCY, and can only be determined
at run time.
-- Tegra SoC options:
- CONFIG_TEGRA_SUPPORT_NON_SECURE
-
- Support executing U-Boot in non-secure (NS) mode. Certain
- impossible actions will be skipped if the CPU is in NS mode,
- such as ARM architectural timer initialization.
-
- Linux Kernel Interface:
CONFIG_OF_LIBFDT
CFG_SYS_NUM_I2C_BUSES
Hold the number of i2c buses you want to use.
- CFG_SYS_I2C_DIRECT_BUS
- define this, if you don't use i2c muxes on your hardware.
- if CFG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
- omit this define.
-
- CFG_SYS_I2C_MAX_HOPS
- define how many muxes are maximal consecutively connected
- on one i2c bus. If you not use i2c muxes, omit this
- define.
-
CFG_SYS_I2C_BUSES
- hold a list of buses you want to use, only used if
- CFG_SYS_I2C_DIRECT_BUS is not defined, for example
- a board with CFG_SYS_I2C_MAX_HOPS = 1 and
- CFG_SYS_NUM_I2C_BUSES = 9:
+ hold a list of buses you want to use
CFG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
{0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
You should define these to the GPIO value as given directly to
the generic GPIO functions.
- CFG_I2C_MULTI_BUS
-
- This option allows the use of multiple I2C buses, each of which
- must have a controller. At any point in time, only one bus is
- active. To switch to a different bus, use the 'i2c dev' command.
- Note that bus numbering is zero-based.
-
CFG_SYS_I2C_NOPROBES
This option specifies a list of I2C devices that will be skipped
will skip addresses 0x50 and 0x68 on a board with one I2C bus
- CFG_SYS_RTC_BUS_NUM
-
- If defined, then this indicates the I2C bus number for the RTC.
- If not defined, then U-Boot assumes that RTC is on I2C bus 0.
-
CONFIG_SOFT_I2C_READ_REPEATED_START
defining this will force the i2c_read() function in
Support for a lightweight UBI (fastmap) scanner and
loader
- CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
- CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
- CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
- CFG_SYS_NAND_ECCPOS, CFG_SYS_NAND_ECCSIZE,
- CFG_SYS_NAND_ECCBYTES
+ CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_SIZE,
+ CONFIG_SYS_NAND_OOBSIZE, CONFIG_SYS_NAND_BLOCK_SIZE,
+ CONFIG_SYS_NAND_BAD_BLOCK_POS, CFG_SYS_NAND_ECCPOS,
+ CFG_SYS_NAND_ECCSIZE, CFG_SYS_NAND_ECCBYTES
Defines the size and behavior of the NAND that SPL uses
to read U-Boot
Configuration Settings:
-----------------------
-- MEM_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
- Optionally it can be defined to support 64-bit memory commands.
-
- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
undefine this when you're short of memory.
globally (CONFIG_CMD_MEMORY).
- CONFIG_SPL_BUILD
- Set when the currently-running compilation is for an artifact
- that will end up in the SPL (as opposed to the TPL or U-Boot
- proper). Code that needs stage-specific behavior should check
- this.
+ Set when the currently running compilation is for an artifact
+ that will end up in one of the 'xPL' builds, i.e. SPL, TPL or
+ VPL. Code that needs phase-specific behaviour can check this,
+ or (where possible) use xpl_phase() instead.
+
+ Note that CONFIG_SPL_BUILD *is* always defined when either
+ of CONFIG_TPL_BUILD / CONFIG_VPL_BUILD is defined. This can be
+ counter-intuitive and should perhaps be changed.
- CONFIG_TPL_BUILD
- Set when the currently-running compilation is for an artifact
- that will end up in the TPL (as opposed to the SPL or U-Boot
- proper). Code that needs stage-specific behavior should check
- this.
+ Set when the currently running compilation is for an artifact
+ that will end up in the TPL build (as opposed to SPL, VPL or
+ U-Boot proper). Code that needs phase-specific behaviour can
+ check this, or (where possible) use xpl_phase() instead.
+
+- CONFIG_VPL_BUILD
+ Set when the currently running compilation is for an artifact
+ that will end up in the VPL build (as opposed to the SPL, TPL
+ or U-Boot proper). Code that needs phase-specific behaviour can
+ check this, or (where possible) use xpl_phase() instead.
- CONFIG_ARCH_MAP_SYSMEM
Generally U-Boot (and in particular the md command) uses
- "u-boot" is an image in ELF binary format
- "u-boot.srec" is in Motorola S-Record format
-By default the build is performed locally and the objects are saved
-in the source directory. One of the two methods can be used to change
-this behavior and build U-Boot to some external directory:
-
-1. Add O= to the make command line invocations:
-
- make O=/tmp/build distclean
- make O=/tmp/build NAME_defconfig
- make O=/tmp/build all
-
-2. Set environment variable KBUILD_OUTPUT to point to the desired location:
-
- export KBUILD_OUTPUT=/tmp/build
- make distclean
- make NAME_defconfig
- make all
-
-Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
-variable.
-
User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
For example to treat all compiler warnings as errors:
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://u-boot.readthedocs.io/en/latest/develop/index.html
+section of https://docs.u-boot.org/en/latest/develop/index.html
where we describe coding standards and the patch submission process.
projects / J-u-boot.git / blobdiff