dpm is the default power management method; and it has three main modes of operating:
cat /sys/class/drm/card0/device/power_dpm_state
returns:
performance
sudo echo performance > /sys/class/drm/card0/device/power_dpm_state
NOTE: Even if GPU is set to performance-mode it does not mean that the GPU is running with highest clockspeeds all the time.
If it is desirable to run the GPU at the highest speeds all the time, even if there is no actual load:
sudo echo high > /sys/class/drm/card0/device/power_dpm_force_performance_level
To give control back to dpm following command is needed to run:
sudo echo auto > /sys/class/drm/card0/device/power_dpm_force_performance_level
A list of all available modes can be found on dri.freedesktop.org.
In order to set clocks and voltages with AMDGPU, first set the performance level to manual:
sudo echo manual > /sys/class/drm/card0/device/power_dpm_force_performance_level
Then, adjust clocks/voltages according to the Linux AMDGPU sysfs documentation with the pp-od-clk-voltage control file.