From: Ben Skeggs

This series adds support for loading and running on top of NVIDIA's GSP-RM firmware, instead of directly programming large portions of the hardware ourselves.

The implementation is a little crude in places, but the goal of this series is to get (more-or-less) GSP-RM support on par with what we already support on HW. Next steps would be to look at what features GSP-RM enables us to more fully support, and clean up the GSP-RM integration once it's known what those will require.

Things should be somewhat faster when running on GSP-RM, as it's able to control GPU clocks, which wasn't possible for us previously.

SVM support is not available when running on top of GSP-RM at this point, due to GPU fault buffers not being implemented yet. This won't effect any real use-case, as SVM is experimental at best in nouveau anyway.

Aside from that, things should more or less work as normal.

GSP-RM support is disabled by default for now (except on Ada, where it's the only option) and can be enabled with nouveau.config=NvGspRm=1.

There'll likely be some nit-picky bugs to sort through, but I don't anticipate any huge disasters. I've smoke-tested this on a selection of GPUs right back to nv50, testing both HW and GSP paths depending on the GPU, and more thoroughly tested on Turing/Ampere/Ada, both discrete and laptop GPUs.

Firmware from NVIDIA is required to enable this support.