Not sure how well the APU's are supported on amdgpu yet, however, I used the amdgpu driver with a RX560 and RX570, in both cases it was incredibly stable and a

Not sure how well the APU's are supported on amdgpu yet, however, I used the amdgpu driver with a RX560 and RX570, in both cases it was incredibly stable and a simple matter of telling the mkinitcpio config to use the amdgpu module and not the radeon module when building the initramfs. KMS should be supported out of the box with amdgpu.