Patches Prep The Merging Of AMDKFD + AMDGPU Linux Drivers

The plans talked about in early July for merging the AMDKFD driver into the AMDGPU DRM driver are moving ahead and out today are the initial patches working towards this merger.

AMDKFD is the graphics vendor's "Kernel Fusion Driver" with the name originating from the Fusion days and is the kernel bits needed for HSA/compute on Radeon graphics hardware.

Fusion memories... Back to the days of the E-350 APU...

AMDKFD has been a separate driver since originally it supported interfacing with the (pre-GCN) Radeon DRM driver too but these days is only focused on the AMDGPU driver for all GCN hardware driver coverage. AMDKFD is what pairs with the ROCm bits in user-space for providing a quite capable and fully open-source compute/OpenCL stack.

Due to AMDGPU being the only "consumer" now for AMDKFD, it makes sense to merge this compute/HSA code into AMDGPU itself. These patches prep for this merger into a single kernel module and take care of migrating the module parameters as well as dropping the CONFIG_HSA_AMD_MODULE support as it will always be built into AMDGPU. It's obviously too late for this merger to happen for Linux 4.19, but it's likely we could see this merger happen for Linux 5.0 as the next cycle.