https://bugs.freedesktop.org/show_bug.cgi?id=79806
--- Comment #5 from Gabor Enyedi enyecz@gmail.com --- One more! If you (or anyone else) don't have the same card, but have some similar issue, you should check if the problem is the same or not (i.e. that the card does not turn up performance, when needed). Give some 3D load (e.g. glmark2), and check /sys/kernel/debug/dri/64/radeon_pm_info.(In reply to comment #3)
Workaround: when resume, execute "echo auto > /sys/class/drm/card0/device/power_dpm_force_performance_level".
How did you do that? It gives me "echo: write error: Invalid argument" on kernel 3.15
One more! If you (or anyone else) don't have the same card, but have some similar issue, you should check if the problem is the same or not (i.e. that the card does not turn up performance, when needed). Give some 3D load (e.g. glmark2), and check /sys/kernel/debug/dri/64/radeon_pm_info.