+- Device tree:
+ CONFIG_OF_CONTROL
+ If this variable is defined, U-Boot will use a device tree
+ to configure its devices, instead of relying on statically
+ compiled #defines in the board file. This option is
+ experimental and only available on a few boards. The device
+ tree is available in the global data as gd->fdt_blob.
+
+ U-Boot needs to get its device tree from somewhere. This can
+ be done using one of the two options below:
+
+ CONFIG_OF_EMBED
+ If this variable is defined, U-Boot will embed a device tree
+ binary in its image. This device tree file should be in the
+ board directory and called <soc>-<board>.dts. The binary file
+ is then picked up in board_init_f() and made available through
+ the global data structure as gd->blob.
+
+ CONFIG_OF_SEPARATE
+ If this variable is defined, U-Boot will build a device tree
+ binary. It will be called u-boot.dtb. Architecture-specific
+ code will locate it at run-time. Generally this works by:
+
+ cat u-boot.bin u-boot.dtb >image.bin
+
+ and in fact, U-Boot does this for you, creating a file called
+ u-boot-dtb.bin which is useful in the common case. You can
+ still use the individual files if you need something more
+ exotic.
+