Nouveau Patch For Linux 7.3 Allows For NVK Vulkan Video Atop NVIDIA NVDEC

This week's round of drm-misc-next patches for staging ahead of the Linux 7.3 kernel merge window bring an exciting change for the open-source NVIDIA "Nouveau" driver. Ready for introduction in the Linux 7.3 merge window is a Nouveau kernel driver patch by Red Hat's David Airlie to support allocating NVDEC channgels via the ABI16 interface. This Nouveau kernel driver change to support NVIDIA video decoding (NVDEC) channel allocations in turn will be used by the Mesa NVK driver for Vulkan Video. There is this pending Mesa merge request dependent upon the Nouveau kernel driver patch. Initially the NVK driver will advertise H.264 video decoding with Vulkan Video. There is work toward H.265 Vulkan Video support too but that is currently wedging the NVIDIA GPU System Processor (GSP). This Nouveau+NVK Vulkan Video support is targeting NVIDIA Turing GPUs and latter in being dependent upon the NVIDIA GSP firmware support and thus older (pre-Turing) NVIDIA GPUs will not be supported. With this patch now part of drm-misc-next for Linux 7.3, hopefully it won't be long before that Vulkan Video H.264 NVK support at least will be merged. This pull request carries that patch along with a few other small Direct Rendering Manager driver patches for the week. The Linux 7.3 merge window is kicking off during the back half of August.