Biggest issues at the moment:I am also interested in helping with Pyra kernel development, my "day job" is FPGA tooling so I'm fairly used to working at a low level including a tiny bit of kernel hacking in the past (not so much on the driver side though, more memory management and interrupt stuff). I can't commit any particular amount of time, I'd mostly be doing this for a bit of variety for what I'm working on but hopefully can manage a few hours a week. I have an OMAP5 dev kit on the way to play with.
It would be great if there were some tasks that weren't really on the critical path, but that would be useful to complete.
* Our TILER patches only work up until kernel 4.19. It doesn't work anymore on higher kernels, so rotation is missing there.
* TILER Rotation doesn't work together with 3D. If I understand correctly what @zmatt said, TILER doesn't free / allow access to the memory area the 3D driver needs, so 3D only works when TILER rotation is disabled. That conflict needs to be resolved
Those are the two main issues. The remaining stuff is optimization, but apart from that, everything works.