[DistroKit] [PATCH] doc: v8a: ROCK 3A: add documentation on writing barebox-only images to SD-Card and NOR Flash

[Johannes Zink <j.zink@pengutronix.de>]

It may be useful to sometimes only write a barebox image to SD-Card,
e.g. for chainloading, TFTP-Boot or if Android Fastboot is used for
flashing the actual full image to a storage medium. Add documentation
on which image to use.

Also add a short section about how to write barebox to the fallback
NOR SPI Flash on the ROCK 3A board.

Signed-off-by: Johannes Zink <j.zink@pengutronix.de>
---
 doc/hardware_v8a_rock3a.rst | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/doc/hardware_v8a_rock3a.rst b/doc/hardware_v8a_rock3a.rst
index 75acd4d84613..3aa5a62ea8bd 100644
--- a/doc/hardware_v8a_rock3a.rst
+++ b/doc/hardware_v8a_rock3a.rst
@@ -5,7 +5,11 @@ Boot Media
 ----------
 
 Copy the image ``platform-v8a/images/rock3a.img`` onto a microSD card. Put the
-microSD card into the Rock 3A and boot it.
+microSD card into the Rock 3A and boot it, the system will autoboot to linux.
+
+If you just want to boot to barebox instead of a full linux image from microSD card
+(e.g. for chainloading or tftpboot),
+copy the image ``platform-v8a/images/barebox-rock3a.norimg`` onto a microSD card instead.
 
 Alternatively, you may put the Rock 3A into MASKROM mode following the `Rock 3
 Hardware User Manual <https://wiki.radxa.com/Rock3/hardware/3a>`_ and boot
@@ -19,6 +23,10 @@ Once Barebox is booted, copy the image ``platform-v8a/images/rock3a.img`` via
 tftp or NFS to the eMMC to persist it. Disable MASKROM mode and reboot the
 board to start from eMMC.
 
+Once booted to linux, you can write ``platform-v8a/images/barebox-rock3a.norimg`` using mtd-utils
+to the NOR flash, which can then be used as fallback boot source whenever booting from microSD
+card or eMMC fails.
+
 Serial Console
 --------------
 
-- 
2.30.2