NVIDIA NVDEC Video Decode Support Sent Out For Linux 5.17, Better Power Management

After the open-source NVIDIA Tegra DRM driver changes intended for Linux 5.16 weren't pulled due to timing, they are back around for Linux 5.17 with most notably the open-source Tegra driver feature pull request introducing NVDEC video decoding.

NVIDIA's Thierry Reding sent out the Linux 5.17 Tegra DRM driver changes to DRM-Next today. Like the work that was intended for Linux 5.16 but un-merged, the big items are a rework to buffer object handling to better match DMA-BUF expectations and then the NVDEC driver.

This NVIDIA Tegra NVDEC support exposes accelerated video decoding for the Tegra X1 (Tegra21) and newer, including the likes of Tegra X2 and Xavier at the moment. NVIDIA contributed the NVDEC code and previously opened up some specifications around NVDEC for assisting in development.

There is the VA-API Tegra user-space driver for making use of the kernel support and allowing multimedia applications targeting the Video Acceleration API (VA-API) to make use of the NVDEC hardware.

This pull request of the Tegra DRM changes for Linux 5.17 has those memory and NVDEC changes. New to this series compared to the prior failed v5.16 pull, there are also power management improvements as part of this work to help in scaling down frequency and voltages when idle to avoid excess heat.