mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-24 03:53:31 +00:00
182d0ba6d6
Update the Anbernic RGxx3 documentation to note that panel detection has been added and how it works. Signed-off-by: Chris Morgan <macromorgan@hotmail.com> Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
56 lines
2 KiB
ReStructuredText
56 lines
2 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0+
|
|
|
|
U-Boot for Anbernic RGxx3 Devices
|
|
=================================
|
|
|
|
This allows U-Boot to boot the following Anbernic devices:
|
|
|
|
- Anbernic RG353M
|
|
- Anbernic RG353P
|
|
- Anbernic RG353PS
|
|
- Anbernic RG353V
|
|
- Anbernic RG353VS
|
|
- Anbernic RG503
|
|
|
|
The correct device is detected automatically by comparing ADC values
|
|
from ADC channel 1. In the event of an RG353V or RG353P, an attempt
|
|
is then made to probe for an eMMC and if it fails the device is assumed
|
|
to be an RG353VS or RG353PS. Based on the detected device, the
|
|
environment variables "board", "board_name", and "fdtfile" are set to
|
|
the correct values corresponding to the board which can be read by a
|
|
boot script to boot with the correct device tree. If the board detected
|
|
is not of type RG503 (which currently has only 1 panel revision) a
|
|
panel detect is then performed by probing a "dummy" display on the DSI
|
|
bus and then querying the display ID. The display ID is then compared
|
|
to a table to get the known compatible string for use in Linux, and
|
|
this string is saved as an environment variable of "panel".
|
|
|
|
FDT fixups are performed in the event of an RG353M to change the device
|
|
name, or in the event the panel detected does not match the devicetree.
|
|
This allows Linux to load the correct panel driver without having to
|
|
know exactly which panel is used (as there is no user distingushable
|
|
way to tell).
|
|
|
|
Building U-Boot
|
|
---------------
|
|
|
|
.. code-block:: bash
|
|
|
|
$ export CROSS_COMPILE=aarch64-linux-gnu-
|
|
$ export BL31=../rkbin/bin/rk35/rk3568_bl31_v1.34.elf
|
|
$ export ROCKCHIP_TPL=../rkbin/bin/rk35/rk3568_ddr_1056MHz_v1.13.bin
|
|
$ make anbernic-rgxx3_defconfig
|
|
$ make
|
|
|
|
This will build ``u-boot-rockchip.bin`` which can be written to an SD
|
|
card.
|
|
|
|
Image installation
|
|
------------------
|
|
|
|
Write the ``u-boot-rockchip.bin`` to an SD card offset 32kb from the
|
|
start. Please note that eMMC booting has not been tested at this time.
|
|
|
|
.. code-block:: bash
|
|
|
|
$ dd if=u-boot-rockchip.bin of=/dev/mmcblk0 bs=512 seek=64
|