AMD Preps More AMDGPU Fixes For Linux 6.1, Still Working On Gang Submit

In addition to Intel having closed out last week by submitting their last batch of feature updates to DRM-Next for kernel graphics driver changes slated for Linux 6.1, AMD engineers also did the same with their likely last major set of AMDGPU driver changes intended for this next kernel cycle.

The Linux 6.1 merge window is opening up in early October and the cut-off for pushing new material to DRM-Next ahead of that cycle is upon us. Thus the Direct Rendering Manager driver maintainers are in a mad rush to get their last bits of feature code ready that they would like to see for the v6.1 kernel, which will be the last major kernel feature release of 2022.

This latest AMDGPU pull includes fixes for new graphics processors featuring the DCN 3.2 display core and separately for the DCN 3.1.4 display core. There are also fixes in AMDGPU for Bus Active Chip Off (BACO) behavior, RAS reliability/serviceability fixes, xGMI fixes, LLVM fixes, new GC CG registers added, and also a number of AMDKFD kernel compute driver fixes.

AMDGPU's Gang Submit functionality continues to be worked on.

Also included as part of this AMDGPU pull is a clean-up to the command stream (CS) code in preparation for the gang submit code. But given the timing, it looks like the AMDGPU gang submit support won't arrive until Linux 6.2 early next year. As noted in that earlier article, the gang submit functionality allows ensuring work is run on multiple engines at the same time -- and that the work won't start until all of the work is ready for execution across the affected engines. Mesa's Radeon Vulkan driver "RADV" is currently one user awaiting the gang submission support for completing the Vulkan mesh shader support and exposing it by default.

The full list of AMDGPU/AMDKFD changes for Friday's pull request can be found on dri-devel.

Earlier this month a prior AMD Radeon pull to DRM-Next sent in more RDNA3 code and a new GPU reset mode for RX 6000 series GPUs, among other changes, as additional driver work to find come Linux 6.1.