smallsolar/u-boot
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Allow boards to initialize the DT at runtime.

Browse Source 
In some boards like the Raspberry Pi the initial bootloader will pass
a DT to the kernel. When using U-Boot as such kernel, the board code in
U-Boot should be able to provide U-Boot with this, already assembled
device tree blob.

This patch introduces a new config option CONFIG_OF_BOARD to use instead
of CONFIG_OF_EMBED or CONFIG_OF_SEPARATE which will initialize the DT
from a board-specific funtion instead of bundling one with U-Boot or as
a separated file. This allows boards like the Raspberry Pi to reuse the
device tree passed from the bootcode.bin and start.elf firmware
files, including the run-time selected device tree overlays.

Signed-off-by: Alex Deymo <deymo@google.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Alex Deymo
2017-04-02 01:25:20 -07:00
committed by Tom Rini
parent 45a6d231b2
commit 82f766d1d2
6 changed files with 38 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
doc/README.fdt-control
View File

@@ -130,6 +130,10 @@ u-boot-dtb.bin which does the above step for you also. If you are using
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.