Intel Prepares To Enable Intel Arc DG2/Alchemist Compute Support On Linux

While every few days it seems like we are writing about new DG2/Alchemist graphics code being prepared for the Linux kernel or related components like Mesa -- and it's been something going on for many months now -- knowing the actual working state of Intel Arc Graphics on Linux hasn't been exactly clear given no formal announcements/communication out of Intel yet as to Linux support expectations / version requirements and not yet having any hardware access. While much of the graphics support has been squared away for Intel Arc DG2/Alchemist as covered in prior articles, it turns out the compute support is still settling but there is now a patch series pending for actually exposing it.

A patch series posted today gets the compute support exposed to Linux user-space with various kernel driver changes, actually exposing the Compute Command Streamer (CCS) engines for Xe_HP software development vehicle and DG2, and various workarounds necessary for proper GPU compute support.

Only with a set of patches sent out today is Intel's Linux kernel graphics driver being prepared to enable compute engine support for DG2 (Alchemist). This should then appear in a released Linux kernel this summer assuming the support is ready to go in time for v5.19.So if you happen to find like Intel Arc A-Series Mobile Graphics, there may be a bit of a wait on the Linux GPU compute support being ready.

This is a bit surprising that this code wasn't already merged, but alas it's been a plethora of patches still coming together and not concise information for outsiders as to the Linux support state for unreleased products. With this patch series only now being on the mailing list, the DG2 (Alchemist) compute support will land kernel-side in Linux 5.19 at the earliest -- assuming the patches are in good shape and get queued up into DRM-Next over the coming weeks. In turn Linux 5.19 stable won't be out until August but at least should be out in time for being used by Fedora 37, Ubuntu 22.10, and other autumn Linux distribution updates.

The Wednesday patch series enabling compute for these latest Intel dGPUs has adjustments needed for the latest GuC micro-controller firmware, exposes the new compute engine ABI for user-space, confirms four CCS engines for DG2/Xe_HP, and has the various workarounds: needing to ensure command streamers are stopped prior to GPU resets to avoid a race condition, activating various firmware-based workaround bits, resetting the RCS/CCS engines before going into the RC6 power state, and a DG2 bug where CCS context switches out while the RCS is running can lead to memory corruption.

This patch series from today is what gets that DG2 compute support ready kernel side. Then in user-space is the Intel Compute-Runtime stack for oneAPI Level Zero and OpenCL support. Intel releases new Compute-Runtime releases every week or two and basically amounts to using the latest release available when you happen to find your hands on Intel Arc graphics processors.