Comment # 26 on bug 1203558 from Matthias Brugger

(In reply to Duy Hua from comment #17)
> At first, we need to run board G2Mv3.0 so we have
> "r8a774a3-hihope-rzg2m-ex-idk-1110wr.dts" config for this board.

I realized that we are missing config options for the serial console driver. I
queued the changes for tumbleweed. This should allow you to use earlycon to see
what happens on the board. As always it will take some time to be published
though. If you want I can provide you with a test kernel that you can use to
test in advance.