Linux 6.5 To Add HuC Loading Support For Intel Meteor Lake

In addition to the drm-intel-next pull earlier this week that brought more Meteor Lake graphics on Linux and VRR eDP support among other changes set for Linux 6.5, on Thursday a new batch of drm-intel-gt-next code was submitted to DRM-Next ahead of this next kernel cycle.

This set of drm-intel-gt-next patches brings support for using large rings for compute contexts, better logging around GuC micro-controller issues, limiting local memory allocation size to succeed on small bars, perf/OA capture robustness improvements on DG2, and a variety of other changes.

Arguably most notable about this latest pull request is adding support for loading the HuC micro-controller firmware for Intel's upcoming Meteor Lake processors. Intel's HuC micro-controller is for offloading some media functionality from the CPU to the GPU and is necessary for hardware acceleration with video codecs like H.265/HEVC.

Intel's old 01.org site characterizes HuC as: "HuC is designed to offload some of the media functions from the CPU to GPU. These include but are not limited to bitrate control, header parsing. For example in the case of bitrate control, driver invokes HuC in the beginning of each frame encoding pass, encode bitrate is adjusted by the calculation done by HuC. Both the HuC hardware and the encode hardcode reside in GPU. Using HuC will save unnecessary CPU-GPU synchronization."

With Meteor Lake, there's a new and improved way of dealing with HuC. That support is going to be in place for the Linux 6.5 kernel.

So HuC loading support for Meteor Lake is the main thing to get excited about with this pull for Linux 6.5.

The Meteor Lake firmware blobs for the GuC and DMC are already in linux-firmware.git while presumably the HuC binaries will be added soon.

The Meteor Lake graphics support appears to be coming along well but as of now in DRM-Next the Meteor Lake graphics remain behind the experimental / "force probe" module option. It's not clear if they'll try to have everything stabilized for Linux 6.5 or will drag out further, but it's approaching the point by which the blessing of it as stable will hopefully happen soon if autumn Linux distribution releases are to provide Meteor Lake graphics support out-of-the-box.

Aside from the Meteor Lake graphics, the rest of the Meteor Lake Linux support appears to be in good shape at least based on my external monitoring of patches. Even the new driver for Meteor Lake's VPU is already mainlined since Linux 6.3.