Linux 4.20~5.0 Bringing More Intel Icelake Graphics Enablement

This week Intel developers sent in their first batch of drm-intel-next feature changes to DRM-Next of new material that will be merged for the next kernel cycle whether it ends up being called Linux 4.20 or likely Linux 5.0.

This first of several feature pull requests for this next kernel cycle is fairly basic and mostly is made up of continued work on Icelake support. Due to summer holidays drawing to an end, there isn't too much feature work part of this week's pull request but more features are expected to be queued in the weeks ahead.

There is a lot of Icelake enablement work for the Linux kernel graphics driver still coming together for these "Gen 11" graphics that succeed Cannonlake. Overall, the Icelake pieces are falling into place, but for now the support is hidden behind an alpha support flag until the Intel developers have been able to run more extensive tests on early silicon. Once they have verified this driver is working well on the internal Icelake processors, they will be dropping this "experimental" tag. There's still plenty of time anyhow until seeing Icelake CPUs, which should be 2020 -- the same year as hopefully seeing Intel's highly-anticipated discrete graphics card.

Some of the Icelake work in this pull request includes a variety of fixes, various power management bits, DDI work, and other display-related work. Icelake work on the user-space OpenGL/Vulkan side also continues.

The only other notable addition is PPGTT (Per-Process Graphics Translation Tables) finally being enabled in full for Ivybridge, Valleyview, and Haswell era graphics hardware.

The complete list of these initial Linux 4.20~5.0 i915 DRM driver kernel changes can be found via this PR.