Linux 4.20 Picks Up 6 x 4K Display Support For Vega 20, Initial RX 590 Support Fixes

Usually this late into a current Linux kernel development cycle the DRM graphics driver fixes don't tend to be too notable, but that's certainly not the case with today's batch of AMDGPU and TTM fixes sent off to the DRM tree.

Highlights of the AMDGPU Linux kernel driver fixes today come down to:

- Support for being able to drive six 4K displays with the upcoming Vega 20 GPUs... Up until now Vega 20 would top out at 4 x 4K displays due to the minimum dcf clock value set, but now that's been corrected with a one line patch that will allow up to six 4K displays to function with the upcoming Radeon Instinct Vega 20 products.

- Also on the Vega 20 front are some PowerPlay fixes.

- The other big highlight of today's fixes pull for 4.20 is the kernel fixes for Radeon RX 590 Linux support when paired with new firmware binaries. But as shared as an update to that article, while these patches do get the display and GPU acceleration working, there are GPU hangs under 3D load... I've heard back that AMD is able to reproduce these issues but no patches are available yet for correcting that issue, hopefully not much longer before the Radeon RX 590 is in good shape for Linux.

These fixes and a few other items corrected are outlined via this pull request.