AMDGPU vs. Radeon GCN 1.0/1.1 Performance On Linux 4.9 DRM-Next

With the forthcoming Linux 4.9 kernel there is experimental AMDGPU Southern Islands support so that original AMD GCN 1.0 GPUs can optionally work with the newer AMDGPU DRM driver rather than the mature Radeon DRM driver. In this article are tests of some AMD graphics cards from GCN 1.0/1.1 era comparing the performance impact of switching the Radeon/AMDGPU kernel driver with this DRM-Next code for Linux 4.9.