Everything else seems to work with amdgpu kernel module. Only xf86-video-amdgpu has problems. Modesetting driver works with amdgpu kernel module. And also vulkan examples with radv and startplasmacompositor command. It is not high priority problem, but there is a bug in either xf86-video-amdgpu or xf86-video-ati driver. Problem may be using radeon and amdgpu simultaneously or using HAINAN GPU with xf86-video-amdgpu.