Bug 485655

Summary:	[Wayland][AMDGPU] VRAM P-state locked at the highest state
Product:	[Plasma] kwin	Reporter:	Pedro Nishiyama <nishiyama.v3>
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	xaver.hugl
Priority:	NOR
Version First Reported In:	6.0.3
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Pedro Nishiyama 2024-04-17 03:31:18 UTC

SUMMARY
KWin on Wayland starts with the VRAM locked at the highest P-state, requiring to change the resolution or refresh rate to allow the GPU to lower it. 

The lock does not happen on X11.

STEPS TO REPRODUCE
1. Start kwin-wayland
2. Run 'cat /sys/class/drm/card0/device/pp_dpm_mclk'
3. VRAM P-state will be set to the highest state and will not allow the GPU to lower it
4. Change resolution or refresh rate
5. Now the GPU can change the p-state according to load

OBSERVED RESULT
$ cat /sys/class/drm/card0/device/pp_dpm_mclk
0: 96Mhz
1: 456Mhz 
2: 675Mhz 
3: 1124Mhz * 

EXPECTED RESULT
P-state should not be locked at the highest state

SOFTWARE/OS VERSIONS
Linux: Artix Linux (radeonsi, navi22, LLVM 17.0.6, DRM 3.57, Mesa 24.0.5, 6.8.5-273-tkg-eevdf)
KDE Plasma Version: 6.0.3
KDE Frameworks Version: 6.1.0
Qt Version: 6.7.0

Comment 1 Zamundaaa 2024-04-17 11:54:00 UTC

KWin doesn't have any control over GPU power states, please report this at https://gitlab.freedesktop.org/drm/amd/-/issues