I own a laptop (Thinkpad E560) with an Intel+Radeon gpu combo. When trying to
run demanding graphical programs with the radeon gpu via dri prime it hangs. In
this context, demanding programs are anything more demanding than glxgears
(which runs fine).

If I boot with radeon.dpm=0 everything runs fine but at the low default clock
speeds. I have been unable to set faster clock speeds via the sysfs interface.

I have tried drm-next from
https://cgit.freedesktop.org/~airlied/linux/?h=drm-next together with the
latest git linux-firmware but the problem is the same.

The problem can be replicated by running 'glmark2 -b texture'. However 'glmark2
-b build' seems to work without any problems.