Intel Appears Ready To Advertise Its DG1 Graphics Card Support On Linux

As I have covered in many Phoronix articles over the past number of months, it's been a lengthy road bringing up the DG1 graphics support on Linux with the Intel open-source engineers having to re-architect their "i915" kernel graphics driver to support device local memory, getting the GuC support into good shape, scheduler changes, beginning to make use of TTM for memory management, user-space API changes, and a ton of other changes in expanding the driver's scope from just catering to integrated graphics. But now it looks like the DG1 Linux support is about to be officially advertised.

Recently I've noted how the Intel DG1 support is pretty much buttoned up for initial support with at least the local vRAM support getting squared away on bleeding-edge kernels and other pieces falling into shape. Intel has even begun working on DG2 open-source driver support with those initial patches coming for Linux 5.15 but expect more work over the months ahead.

With the DG1 support now getting settled, patches were posted today for actually being able to expose the support by default. Up to this point the DG1 PCI IDs weren't exposed in the Linux kernel driver by default and thus wouldn't bind to the graphics card unless using a specially built kernel. The DG1 IDs were hidden behind the "CONFIG_DRM_I915_UNSTABLE_FAKE_LMEM" kernel build-time option given the local memory support being experimental. But now it's at least in a state where it can be enabled by default.

Today's patch allows the DG1 graphics card PCI IDs to be enabled by default and also drops some other driver checks around that "UNSTABLE_FAKE_LMEM" kernel build option. That patch description notes:

DG1 has support for local memory, which requires the usage of the lmem placement extension for creating bo's, and memregion queries to obtain the size. Because of this, those parts of the uapi are no longer guarded behind FAKE_LMEM.

According to the pull request referenced below, mesa should be mostly ready for DG1. VK_EXT_memory_budget is not hooked up yet, but we should definitely just enable the uapi parts by default.

The Mesa PR is pending for re-enabling DG1 with the Iris Gallium3D and ANV Vulkan drivers plus also adding the SG1 grapics card PCI IDs.

For now this kernel enablement patch is just residing on the kernel mailing list. The deadline is quickly approaching for getting new material into DRM-Next ahead of the Linux 5.15 cycle, so we'll see if this formal enablement happens then or is diverted to the 5.16 kernel later in the year.

At least with all of the groundwork now in place, DG2 and future Intel discrete graphics should see much more punctual enablement by this prominent open-source graphics driver stack. DG2 is sampling to external developers now with rumors of a possible launch at CES 2022.