https://bugzilla.kernel.org/show_bug.cgi?id=205497
--- Comment #11 from Alex Deucher (alexdeucher@gmail.com) --- (In reply to Trek from comment #7)
by default, radeontop calls amdgpu_read_mm_registers, amdgpu_query_info and amdgpu_query_sensor_info, but it can be forced by the command line to read BAR from /dev/mem
If you access the BAR directly you will likely have problems in certain power saving modes.
Can someone test the patch?