generic source base.
To enable this feature, add CONFIG_OF_CONTROL to your board config file.
-It is currently supported on ARM, x86 and Microblaze - other architectures
-will need to add code to their arch/xxx/lib/board.c file to locate the
-FDT. Alternatively you can enable generic board support on your board
-(with CONFIG_SYS_GENERIC_BOARD) if this is available (as it is for
-PowerPC). For ARM, Tegra and Exynos5 have device trees available for
-common devices.
What is a Flat Device Tree?
CONFIG_SPL_FRAMEWORK, then u-boot.img will be built to include the device
tree binary.
+If CONFIG_OF_BOARD is defined, a board-specific routine will provide the
+device tree at runtime, for example if an earlier bootloader stage creates
+it and passes it to U-Boot.
+
If CONFIG_OF_HOSTFILE is defined, then it will be read from a file on
startup. This is only useful for sandbox. Use the -d flag to U-Boot to
specify the file to read.
You cannot use more than one of these options at the same time.
To use a device tree file that you have compiled yourself, pass
-DEV_TREE_BIN=<filename> to 'make', as in:
+EXT_DTB=<filename> to 'make', as in:
- make DEV_TREE_BIN=boot/am335x-boneblack-pubkey.dtb
+ make EXT_DTB=boot/am335x-boneblack-pubkey.dtb
Then U-Boot will copy that file to u-boot.dtb, put it in the .img file
if used, and u-boot-dtb.bin.
Be aware that this environment variable is checked prior to relocation,
when only the compiled-in environment is available. Therefore it is not
possible to define this variable in the saved SPI/NAND flash
-environment, for example (it will be ignored).
+environment, for example (it will be ignored). After relocation, this
+variable will be set to the address of the newly relocated fdt blob.
+It is read-only and cannot be changed. It can optionally be used to
+control the boot process of Linux with bootm/bootz commands.
To use this, put something like this in your board header file: