I can't believe I'm typing this, but - with some caveats - Quake II RTX compiles and runs under Fedora 37 with an RDNA2 Radeon on Power9. The gotchas:
* If you're copying your Windows folder over and you care about preserving your saved games, make sure the contents of Q2RTX/baseq2/save are moved to ~/.quake2rtx/baseq2/save. If you don't, and you leave the Windows save folder intact, the executable will throw an error when trying to load a new game or save because it can't rectify the presence of the Windows folder with the presence of the Linux folder.
* For some reason I can't get timedemo functionality to work - attempting to load a timedemo from the console results in "Couldn't load maps/demo1.dm2.bsp: No such file or directory".
EDIT: * The game may bomb out at startup complaining that it can't find a Vulkan-capable GPU (despite the logs indicating it successfully queried both your Vulkan GPU as well as llvmpipe). In that case, manually edit ~/.quake2rtx/baseq2/q2config.cfg and change the line seta ray_tracing_api value from "auto" to "query". I tried setting this to “pipeline” on a lark to test the other raytracing method it supports, and that crashes the executable because it apparently can’t find the extensions it’s looking for.
Nevertheless it runs at around 60 fps at 1080p on an RX 6600 with resolution scaling set to 65%, which doesn't trail the Windows version with the same card too much at all. There is some minor visual corruption at the periphery of the screen, but with some more testing and bugfixes that can probably be fixed. Back to Stroggos I go...