DRM Scheduler Improvement, New Epoch Counter, Other DRM Work For Linux 5.9

Following the drm-misc-next pull request to DRM-Next last week that exposes VRR ranges via DebugFS and other improvements, another round of DRM-Misc-Next material has now been sent in for queuing ahead of the Linux 5.9 cycle.

The newest DRM-Misc changes making their way for Linux 5.9 include:

- The introduction of a new epoch counter for DRM connectors. Initially wired up for the Intel DRM driver, this counter is used for determining if the display EDID has changed or the connection status. In turn the drivers can send out a uevent when such change occurs.

- A patch by AMD to improve the DRM scheduler (what formerly was just the AMDGPU scheduler before other drivers expressed interest). This scheduler improvement aims for better job distribution with multiple queues. The numbers provided by AMD for the patch do indeed show much better distribution of scheduling when dealing with multiple SDMA and compute queues.

- A change to the TTM memory management code so the translation table (TT) creation is now on-demand. The TT creation is for allocating a TTM structure for a given buffer object.

- Various additions and updates to the smaller DRM drivers like those used in the embedded space.

The full list of changes via the pull request.