amdgpu_device_mm_access
void amdgpu_device_mm_access(struct amdgpu_device *adev, loff_t pos,
amdgpu_device_mm_access(adev, pos, buf, size, write);
amdgpu_device_mm_access(adev, aligned_pos, &value, 4, false);
amdgpu_device_mm_access(adev, aligned_pos, &value, 4, true);
amdgpu_device_mm_access(adev, aligned_pos, buf, 4, write);
amdgpu_device_mm_access(adev, *pos, &value, 4, true);