Comment # 25 on bug 93217 from Mike Lothian

As you can see from the dmesg - I've enabled it

It seems to be a runpm problem, with amdgpu.runpm=1 the chip now reinitialises
when DRI_PRIME=1 is passed but it seems the speeds don't ramp up and there's a
warning about themal values. With amdgpu.runpm=0 everything still seems to work
but of course the card doesn't switch off when not in use