It Looks Like AMD Is About To Post The Open-Source Radeon "Navi" Driver Code

It looks like the AMD posting of the open-source Radeon driver enablement code for next-gen "Navi" GPUs is imminent. In fact, the first bits of it quietly were pushed out today.

In my habitual monitoring of prominent Git repositories, I noticed today the AMDGPU LLVM back-end began seeing "gfx1010" commits. Yep, GFX1010 is Navi!

So far there's the target definitions that includes workarounds for different architecture bugs and a few new instructions. There's also the SGPR register changes for GFX10 though not too revealing.

As of writing, the AMDGPU kernel driver changes and Gallium3D support changes (or AMDVLK Vulkan) code has yet to be posted for review. But with GFX10(10) changes now hitting LLVM Git, it looks like the legal review is clearing up that usually is the last step before allowing the code to be published at AMD... Hopefully we'll see the start of the kernel and Mesa patches today or in the days ahead. At least with past Radeon driver enablement series, the work has generally started up about the same time across the different software components with not much of a timing difference.

Though on the kernel side, unfortunately based upon the current cadence, it's unlikely to see the Navi code merged for the upcoming Linux 5.2 kernel cycle. The cut-off of new material for DRM-Next is upon us for Linux 5.2 and with Navi likely requiring significant DRM driver changes, it's unlikely that will be reviewed and squared away for merging in short order. Thus it would need to hold off until the Linux 5.3 cycle.

Linux 5.1 will be out in early May, Linux 5.2 should then debut roughly in July, and Linux 5.3 as stable likely in September. Linux 5.3 at least is what should be in Ubuntu 19.10, Fedora 31, etc and will presumably be the first kernel with mainline Radeon Navi support. Assuming Navi rumors pan out and we see the Navi launch this summer, we won't see out-of-the-box mainline kernel support but at least the kernel bits should be out in time for the autumn Linux distribution updates. For those not comfortable riding DRM-Next/Git kernels, at least AMDGPU-PRO / Radeon Software for Linux will presumably be offering their hybrid binary driver package for supported LTS/enterprise distributions on launch-day.

On the Mesa side, the Mesa 19.1 feature freeze is starting next week, thus making RadeonSI Navi (and hopefully Navi RADV support, which comes unofficially) a feature for Mesa 19.2 that is then releasing as stable in August and also out in time for fall Linux distribution updates.