Hm, I built the 6.1 kernel using bsp stable, but IIUC that does not build https://github.com/radxa/kernel/tree/linux-6.1-stan-rkr1 , but mainline with some patches included in bsp
BSP_GIT="https://kernel.googlesource.com/pub/scm/linux/kernel/git/stable/linux.git"
BSP_TAG="v6.1.68"
I get even worse results than on 6.6.
The radxa kernel linux-6.1-stan-rkr1 is likely very different. Please how did you build your kernel, what .config did you use?
I am sorry for bothering you, but this situation bugs me too. Kind of looks like a mess in the radxa kernel projects.
Thanks a lot,
Pavel