I am running an Orange Pi 5 (not Max) in production with NetBSD 10 and EDK2. It works perfectly.Were there any EDK2 settings that you needed to change? Your dmesg could be helpful.
Same: https://dmesgd.nycbug.org/dmesgd?do=view&id=7151I don't remember needing to change settings, like one does for > 3 gigs or working wifi on Raspberry Pis.
I am more interested in FDT drivers in the long term but I also got the board to be a faster aarch64 build system, so being able to boot with EDK2 now would be good.
The Orange Pi 5 is pretty darned fast. Mine's in colo, else I'd be testing NetBSD 11 and other things.
John