Most notable to the DRM changes for Linux 4.6 is finally having the signed firmware support from NVIDIA Corp for Maxwell. This means that when having NVIDIA's firmware blobs, Linux 4.6, and the latest Mesa, there is now working open-source GeForce GTX 900 series support with OpenGL hardware acceleration! But there isn't yet re-clocking and other functionality. I'll deliver some preliminary open-source numbers later this week. It took NVIDIA a long time to get the signed firmware support out there, but it's now available.
Besides the GM200/Maxwell support in Nouveau, there is also new GM20B clock driver support from NVIDIA for the Tegra X1. Additionally there is power sensors work and other changes.
On the Intel DRM driver side, a big change is trying for FBC and PSR support by default -- frame-buffer compression and panel self refresh handling. These changes lower the power consumption of supported Intel hardware. The Intel i915 DRM driver also has more atomic display work, runtime power management changes, GEM fixes, GuC firmware scheduler enhancements, and other improvements.
On the AMD front, Linux 4.6 isn't particularly huge but one welcome feature is now GPU reset support for the AMDGPU DRM driver -- so the GPU will hopefully be reset when it's hung, which is a problem I've had multiple times while testing this new driver. There is also ACP support for i2s audio support for Carrizo APUs, and various optimizations when it comes to command submission, the GPUVM, and the GPU scheduler.
Exciting some will be that there's finally GPU switching for Pre-Retina MacBook Pro computers with the latest DRM updates. Also there is going to be much faster Raspberry Pi 3D/OpenGL performance with Linux 4.6.
Some of the other changes include the new ARM HDLCD driver, DX10 gen mipmaps support in VMWGFX, Exynos 5422/5420 support in the Samsung DRM driver, Etnaviv now better supports Freescale i.MX6 systems, DMA-BUF import support for the OMAP DRM driver, and other changes. The DRM pull request for the Linux 4.6 kernel merge window can be viewed in full via the LKML.