Last Minute AMD GFX12 Changes For RadeonSI Driver Enable ACO For RDNA4

Ahead of AMD's approaching RDNA4 next-generation graphics card launch, today a set of last minute improvements to the AMD GFX12 graphics IP were merged to Mesa 25.0 for the open-source Linux graphics driver support.

Qiang Yu at AMD submitted various GFX12 updates to Mesa 25.0-devel, the graphics IP version for RDNA4. There is support for more modifiers but also work on the GFX12 ACO compiler back-end support. ACO is the compiler back-end developed by Valve originally for the RADV Vulkan driver but with time adapted to the RadeonSI Gallium3D driver as an alternative to the AMDGPU LLVM shader compiler back-end.

"Add more supported modifiers which may be exported.

Others are for GFX12 ACO compilation. I've tested ACO with piglit/dEQP/KHR-GL, with the ACO fixes in other MRs, no regression compared to LLVM now. So enable it."

With the now merged code, RadeonSI ACO can be used on GFX12/RDNA4 if desired.

At least from my external observations it's looking like the open-source Linux driver support should be in fairly good shape for launch-day support with the upcoming RDNA4 Radeon graphics cards.