AMD Sends Out Initial Linux Driver Support For "Renoir" APUs

AMD is striking well over the past month with their Linux hardware bring-up. In the past month we've seen the Navi 10/12/14 support get in order for Linux as well as support for the future Vega-based Arcturus GPU and now we see the initial enablement patches for their next-generation APUs, Renoir.

Sent out today was the initial 27 patches amount to around two thousand lines of code (roughly half of which is just header files) for bringing up this next-gen AMD APU.

Renoir is the successor to current AMD Picasso APUs and are said to be based on the new Zen 2 architecture while incorporating a Navi GPU... Well, at least originally what rumors/leaks reported. These code patches indicate Renoir to be based on Raven/Vega as opposed to Navi. Not a whole lot is known about Renoir publicly and are not expected to hit the shelves until 2020.

Renoir is based on Navi (or actually Vega?) so it isn't a whole lot of new code from the AMDGPU kernel driver side, but still, we aren't accustomed to seeing this Linux driver support so early in advance of launch (potentially ~6+ months). It could be a sign that there could be some interesting design wins or Chromebooks warranting good Linux support at launch or it could just be that they've hit a good punctual stride on new platform enablement, but whatever the case is it's certainly welcomed, especially after the very bumpy Raven Ridge experience on Linux.

These patches do confirm VCN 2.0 support on Renoir while most of he code changes come down to slight differences around power management / clock gating, golden register settings, and firmware bits. The AMDGPU code though does seem to indicate this as Vega-based rather than Navi as was rumored. So unless they end up marketing it weirdly (just like Kabylake-G with VegaM really being Polaris), that is what's happening.

For now at least Renoir's graphics is just represented by a single PCI ID, 0x1636.

This currently experimental (hidden behind feature flag) AMD Renoir support should be on its way to DRM-Next soon for premiering in Linux 5.4 while over the coming kernel cycles should stabilize and be flipped on by default, hopefully well ahead still of the hardware's expected launch.