rk3399_rockchip-uboot/doc/README.fdt-control

4 # SPDX-License-Identifier:	GPL-2.0+
7 Device Tree Control in U-Boot
10 This feature provides for run-time configuration of U-Boot via a flat
11 device tree (fdt). U-Boot configuration has traditionally been done
13 make it possible for a single U-Boot binary to support multiple boards,
18 The fdt is a convenient vehicle for implementing run-time configuration
25 format, and a library is already available in U-Boot (libfdt) for
29 and embedding it in your U-Boot image. This is useful since it allows
30 U-Boot to configure itself according to what it finds there. If you have
39 ---------------------------
49 	Documentation/devicetree/booting-without-of.txt
53 	http://lists.ozlabs.org/listinfo/devicetree-discuss
59 -----
74 	$ dtc -v
75 	Version: DTC 1.2.0-g2cb4b51f
91 ----------------------------------------
104 -------------
119 the U-Boot image (including u-boot.bin). This is suitable for debugging
123 a u-boot.dtb file alongside u-boot.bin. A common approach is then to
126 	cat u-boot.bin u-boot.dtb >image.bin
128 and then flash image.bin onto your board. Note that U-Boot creates
129 u-boot-dtb.bin which does the above step for you also. If you are using
130 CONFIG_SPL_FRAMEWORK, then u-boot.img will be built to include the device
133 If CONFIG_OF_BOARD is defined, a board-specific routine will provide the
135 it and passes it to U-Boot.
138 startup. This is only useful for sandbox. Use the -d flag to U-Boot to
146 	make EXT_DTB=boot/am335x-boneblack-pubkey.dtb
148 Then U-Boot will copy that file to u-boot.dtb, put it in the .img file
149 if used, and u-boot-dtb.bin.
155 when only the compiled-in environment is available. Therefore it is not
159 It is read-only and cannot be changed. It can optionally be used to
166 Build:
168 After board configuration is done, fdt supported u-boot can be build in two ways:
169 1)  build the default dts which is defined from CONFIG_DEFAULT_DEVICE_TREE
171 2)  build the user specified dts file
172     $ make DEVICE_TREE=<dts-file-name>
176 -----------
178 U-Boot is designed to build with a single architecture type and CPU
179 type. So for example it is not possible to build a single ARM binary
182 the CPU families within arch/arm/cpu/arm926ejs (omap or at91) at build
183 time. Similarly you cannot build for multiple cpu types or
197 --
199 1-Sep-11