AMD Has A Bit More RDNA3 Graphics Driver Code Ready For Linux 5.20

While the cutoff of new feature work to queue in DRM-Next for the next kernel cycle usually ends around the "-rc6" time of the current cycle, AMD has submitted a few last minute items for Linux 5.20 ahead of its merge window opening next week.

On Tuesday some late items including "a few new things" were sent via a pull request to DRM-Next. We are just days out from the next merge window, but the regression risk is low since the focus of these AMDGPU changes are for new IP blocks added with 5.20. So due to being for new hardware not currently supported by existing kernels, these changes will likely be fine coming in so soon before this next merge window.

Among the changes are VCN4 video coding fixes, RAS support for the UMC 8.10 controller (presumably used by the next-gen Instinct MI300), Audio Co-Processor (ACP) support for their Jadeite platforms, run-time power management fixes, exposing additional GFXOFF data/statistics via DebugFS, floating point code clean-ups around new DCN display blocks, fixing DCN display code support for PowerPC, and a variety of other fixes.

Also notable with this last minute pull request is now exposing IP version information to user-space for consumption by the user-mode drivers, like RadeonSI Gallium3D, AMDVLK, RADV, and ROCm code. This user-space information around the IP blocks is needed for new hardware enablement as part of their new "block-by-block" driver enablement approach.

Earlier in prior pull requests for Linux 5.20's DRM-Next were a lot of new IP blocks around RDNA3 with that being one of the main focuses for this cycle.

The full list of last minute AMDGPU feature changes for Linux 5.20 can be found via this pull request. Linux 5.20 stable will be out in early October. It's not clear though to outsiders if Linux 5.20 will be good enough for the basic RDNA3 GPU support at launch or if there is more pressing work still yet-to-be-merged due to their block-by-block enablement strategy. We'll see once RDNA3 launches and I can provide Linux benchmarks, but fingers crossed that the RDNA3 support is good enough for launch-day support on Linux 5.20... Linux 5.20 is also the minimum version for initial Arc Graphics desktop cards.