Crocus: Working On Gallium3D For Old Intel Graphics

Raised during the recent discussion over looking at removing Mesa's classic drivers from the mainline tree this year is that there still exists an effort trying to create an Intel Gallium3D driver for older pre-Broadwell graphics currently only served by the i965 classic driver. That Crocus effort continues to be worked on but isn't yet mainline.

Crocus is the in-development Gallium3D driver focused on Intel Gen4 (i965 chipset) graphics through Gen7/Gen7.5 graphics with Haswell. Intel's modern Iris Gallium3D driver is what provides the OpenGL support for Gen8 Broadwell graphics and newer.

Crocus started off as a fork of the Intel Iris code from a year ago and then extended backwards with a focus on that Gen4 through Gen7 Intel hardware. The effort was initiated by Ilia Mirkin who is known for his Nouveau driver contributions while well known open-source graphics driver developer David Airlie has also been involved in this effort. Meanwhile for prior to Gen4 graphics there is i915g albeit not seeing any real activity in years given the age of the hardware and of limited usefulness these days.

Crocus may let some old Intel graphics going back to the GMA 3000 series live on a bit longer in Mesa...

The Crocus Gallium3D driver continues to be hacked on, most recently just a few hours ago. The code is maintained via Airlie's Crocus branch at least until an attempt is made to mainline the code upstream in Mesa.

The code remains a work-in-progress and hence why it isn't yet mainlined. Along with David Airlie and Ilia Mirkin, former Intel open-source developer Eric Anholt has also been contributing some patches to Crocus. Intel developers have not been officially contributing to this driver with Broadwell going as far back as their current support interests in the Iris space or Skylake with their compute stack.

Thanks to Gallium3D yielding slimmer drivers, it's possible they will get up to scratch in short order for Crocus to at least merge the code. This will provide at least some reprieve for those concerned over the prospects of the i965 classic driver being removed from mainline. However, don't expect any miracles out of Crocus as the hardware is quite slow at this point. It will at least be fun to see how Crocus can compare to i965 classic. Upgrading to even newer, used hardware would still yield a much more performant experience and greater power efficiency. Especially with Intel hardware of this vintage requiring the multitude of software mitigations for speculative execution vulnerabilities further decreasing the system's performance. In any case, fun to see more Gallium3D activity happening and hopefully the flushing out of classic Mesa drivers soon from the mainline tree.