Hi Christian,
On 1/25/21 8:18 AM, Christian Hewitt wrote:
This patch adapts the panfrost pre-defined thresholds change [0] to the lima driver to improve real-world performance. The upthreshold value has been set to ramp GPU frequency to max freq faster (compared to panfrost) to compensate for the lower overall performance of utgard devices.
[0] https://patchwork.kernel.org/project/dri-devel/patch/20210121170445.19761-1-...
Signed-off-by: Christian Hewitt christianshewitt@gmail.com
I have been using Kodi as my test application. If you scroll in library views with hundreds of list items and the panfrost values the slow GPU ramp up is quite noticeable and the GUI feels sluggish. As everything lima runs on is inherently slower than panfrost using devices I believe it's better to ramp up to max freq quicker.
It's quite low value for the upthreshold, but I believe you have experimented and observed that a bit higher (30, 40?) don't work well. I don't know the Kodi system, though.
You can check if the other frequencies are also used in statistics for devfreq device: cat /sys/class/devfreq/<your_gpu>/trans_stats
If they are also used, then it OK (better than stuck at min freq).
Regards, Lukasz