diff options
Diffstat (limited to 'doc/device-tree-bindings/config.txt')
| -rw-r--r-- | doc/device-tree-bindings/config.txt | 83 |
1 files changed, 67 insertions, 16 deletions
diff --git a/doc/device-tree-bindings/config.txt b/doc/device-tree-bindings/config.txt index 6cdc16d..85379fb 100644 --- a/doc/device-tree-bindings/config.txt +++ b/doc/device-tree-bindings/config.txt @@ -5,15 +5,39 @@ A number of run-time configuration options are provided in the /config node of the control device tree. You can access these using fdtdec_get_config_int(), fdtdec_get_config_bool() and fdtdec_get_config_string(). +These options are designed to affect the operation of U-Boot at runtime. +Runtime-configuration items can help avoid proliferation of different builds +with only minor changes, e.g. enabling and disabling console output. Items +here should be those that can usefully be set by the build system after U-Boot +is built. + Available options are: -silent-console - If present and non-zero, the console is silenced by default on boot. +bootcmd (string) + Allows overwriting of the boot command used by U-Boot on startup. If + present, U-Boot uses this command instead. Note that this feature can + work even if loading the environment is disabled, e.g. for security + reasons. See also bootsecure. + +bootdelay (int) + This allows selecting of the U-Boot bootdelay, to control whether U-Boot + waits on boot or for how long. This allows this option to be configured + by the build system or by a previous-stage binary. For example, if the + images is being packed for testing or a user holds down a button, it may + allow a delay, but disable it for production. -no-keyboard - Tells U-Boot not to expect an attached keyboard with a VGA console +u-boot,boot-led (string) +u-boot,error-led (string) + This is used to specify the label for an LED to indicate an error and + a successful boot, on supported hardware. -u-boot,efi-partition-entries-offset +bootsecure (int) + Indicates that U-Boot should use secure_boot_cmd() to run commands, + rather than the normal CLI. This can be used in production images, to + restrict the amount of parsing done or the options available, to cut + back on the available surface for security attacks. + +u-boot,efi-partition-entries-offset (int) If present, this provides an offset (in bytes, from the start of a device) that should be skipped over before the partition entries. This is used by the EFI/GPT partition implementation when a device @@ -21,17 +45,18 @@ u-boot,efi-partition-entries-offset This setting will override any values configured via Kconfig. -u-boot,mmc-env-partition - if present, the environment shall be placed at the last - CONFIG_ENV_SIZE blocks of the partition on the - CONFIG_SYS_MMC_ENV_DEV. +kernel-offset (int) + This allows setting the 'kernaddr' environment variable, used to select + the address to load the kernel. It is useful for systems that use U-Boot + to flash a device, so the scripts that do this know where to put the + kernel to be flashed. - if u-boot,mmc-env-offset* is present, this setting will take - precedence. In that case, only if the partition is not found, - mmc-env-offset* will be tried. +load-environment (int) + Allows control over whether U-Boot loads its environment after + relocation (0=no, 1 or not present=yes). -u-boot,mmc-env-offset -u-boot,mmc-env-offset-redundant +u-boot,mmc-env-offset (int) +u-boot,mmc-env-offset-redundant (int) If present, the values of the 'u-boot,mmc-env-offset' and/or of the u-boot,mmc-env-offset-redundant' properties overrides CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND, respectively, @@ -42,12 +67,38 @@ u-boot,mmc-env-offset-redundant will point at the beginning of a LBA and values that are not LBA-aligned will be rounded up to the next LBA address. -u-boot,spl-payload-offset +u-boot,mmc-env-partition (int) + if present, the environment shall be placed at the last + CONFIG_ENV_SIZE blocks of the partition on the + CONFIG_SYS_MMC_ENV_DEV. + + if u-boot,mmc-env-offset* is present, this setting will take + precedence. In that case, only if the partition is not found, + mmc-env-offset* will be tried. + +u-boot,no-apm-finalize (bool) + For x86 devices running on coreboot, this tells U-Boot not to lock + down the Intel Management Engine (ME) registers. This allows U-Boot to + access the hardware more fully for platforms that need it. + +u-boot,no-keyboard (bool) + Tells U-Boot not to expect an attached keyboard with a VGA console. + +rootdisk-offset (int) + This allows setting the 'rootdisk' environment variable, used to select + the address to load the rootdisk. It is useful for systems that use + U-Boot to flash a device, so the scripts that do this know where to put + the root disk to be flashed. + +silent-console (int) + If present and non-zero, the console is silenced by default on boot. + +u-boot,spl-payload-offset (int) If present (and SPL is controlled by the device-tree), this allows to override the CONFIG_SYS_SPI_U_BOOT_OFFS setting using a value from the device-tree. -sysreset-gpio +sysreset-gpio (string) If present (and supported by the specific board), indicates a GPIO that can be set to trigger a system reset. It is assumed that such a system reset will effect a complete platform reset, |