Rock 4C+ u-boot UART serial console

[gustav-heinrich]

Hi,

I have two Rock 4C+ boards. Apparently, they are from different batches. For the older one of them, u-boot debug output on the serial console works perfectly fine:

When booting the newer board with the same image [1], however, I get only garbage:

Once the kernel kicks in, the serial console over UART works fine.

Any ideas?

Cheers
GH

[1] https://github.com/radxa-build/rock-4c-plus/releases/download/b60/rock-4c-plus_debian_bullseye_cli_b60.img.xz