David Airlie pulled the Nouveau DRM feature update into DRM-Next last night for the Nouveau DRM driver. This pull includes some fixes/improvements for the NVIDIA Tegra K1's GK20A graphics processor, better support for high frequency HDMI modes, the Nouveau pstate control interfaces were moved from sysfs to debugfs, there is now support for PCI Express link speed changes, and various other fixes.
More details on the Novueau DRM driver changes you'll be able to find with the Linux 4.5 kernel can be found via this pull request. Sadly absent are any overhaul to the re-clocking support and the hardware-acceleration support for the GeForce GTX 900 series. The GTX 900 3D support is still being held up by NVIDIA not yet releasing the signed firmware images for these Maxwell GPUs.