AMDGPU Changes Queued For Linux 4.11: Power/TTM Changes, No DC/DAL

Alex Deucher of AMD sent in the Radeon/AMDGPU DRM driver changes today to DRM-Next for then merging into the Linux 4.11 kernel a few weeks down the road.

There are some notable additions to the AMDGPU DRM driver for this next kernel cycle. But for those looking forward to the DC (DAL) display code rework as the stepping stone towards HDMI 2.0 / atomic mode-setting / HDMI/DP audio / FreeSync / much more, that code isn't yet ready. We weren't quite expecting it to be for Linux 4.11, but we could always have hoped, especially some Linux gamers/users are waiting rather anxiously for this support. Hopefully we'll see it happen for Linux 4.12?

Also, nothing new to report on for SI/CIK support enabled by default for AMDGPU. That's something we'll likely see some Linux distribution vendors first decide to change over from Radeon DRM to AMDGPU for the GCN 1.0/1.1 hardware in order to ensure there is sufficient support and their user-space stack won't break.

Anyhow, what there is for the Linux 4.11 updates include more power and clock-gating improvements, preliminary SR-IOV support (PCI Express single root input/output virtualization), TTM buffer priority support, TTM eviction fixes, other TTM memory management related work, removal of some Southern Islands DPM power management quirks, PowerPlay improvements, and various driver clean-ups.

So the AMDGPU Linux 4.11 changes basically come down to the seemingly never-ending work on power management, the recent efforts around AMD GPU virtualization support, TTM memory management work, and various other clean-ups. This pull request has 4838 insertions and 6122 deletions.

There's still a bit of time left for AMD to queue up additional feature work for Linux 4.11. Besides the DC/DAL work not making it, also not found as part of this Linux 4.11 feature pull is AMD Vega support. Linux 4.11 will probably be the last kernel to be released as stable before Vega GPUs ship, but if at least Vega lands in Linux 4.12 there will still be mainline support available albeit not yet in a released kernel for launch day, similar to the state of AMD Polaris in the kernel Git for launch.

The list of changes for this Radeon/AMDGPU Linux 4.11 feature pull can be found via this mailing list message.