linux/drivers/gpu/drm/amd
chen gong cbd2d08c74 drm/amd/powerpay: Disable gfxoff when setting manual mode on picasso and raven
[Problem description]
1. Boot up picasso platform, launches desktop, Don't do anything (APU enter into "gfxoff" state)
2. Remote login to platform using SSH, then type the command line:
	sudo su -c "echo manual > /sys/class/drm/card0/device/power_dpm_force_performance_level"
	sudo su -c "echo 2 > /sys/class/drm/card0/device/pp_dpm_sclk" (fix SCLK to 1400MHz)
3. Move the mouse around in Window
4. Phenomenon :  The screen frozen

Tester will switch sclk level during glmark2 run time.
APU will enter "gfxoff" state intermittently during glmark2 run time.
The system got hanged if fix GFXCLK to 1400MHz when APU is in "gfxoff"
state.

[Debug]
1. Fix SCLK to X MHz
	1400: screen frozen, screen black, then OS will reboot.
	1300: screen frozen.
	1200: screen frozen, screen black.
	1100: screen frozen, screen black, then OS will reboot.
	1000: screen frozen, screen black.
	900:  screen frozen, screen black, then OS will reboot.
	800:  Situation Nomal, issue disappear.
	700:  Situation Nomal, issue disappear.
2. SBIOS setting: AMD CBS --> SMU Debug Options -->SMU Debug --> "GFX DLDO Psm Margin Control":
	50 : Situation Nomal, issue disappear.
	45 : Situation Nomal, issue disappear.
	40 : Situation Nomal, issue disappear.
	35 : Situation Nomal, issue disappear.
	30 : screen black.
	25 : screen frozen, then blurred screen.
	20 : screen frozen.
	15 : screen black.
	10 : screen frozen.
	5  : screen frozen, then blurred screen.
3. Disable GFXOFF feature
	Situation Nomal, issue disappear.

[Why]
Through a period of time debugging with Sys Eng team and SMU team, Sys
Eng team said this is voltage/frequency marginal issue not a F/W or H/W
bug. This experiment proves that default targetPsm [for f=1400MHz] is
not sufficient when GFXOFF is enabled on Picasso.

SMU team think it is an odd test conditions to force sclk="1400MHz" when
GPU is in "gfxoff" state,then wake up the GFX. SCLK should be in the
"lowest frequency" when gfxoff.

[How]
Disable gfxoff when setting manual mode.
Enable gfxoff when setting other mode(exiting manual mode) again.

By the way, from the user point of view, now that user switch to manual
mode and force SCLK Frequency, he don't want SCLK be controlled by
workload.It becomes meaningless to "switch to manual mode" if APU enter "gfxoff"
due to lack of workload at this point.

Tips: Same issue observed on Raven.

Signed-off-by: chen gong <curry.gong@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2020-05-22 13:41:43 -04:00
..
acp drm: amd/acp: fix broken menu structure 2020-03-13 11:52:35 -04:00
amdgpu drm/amd/powerpay: Disable gfxoff when setting manual mode on picasso and raven 2020-05-22 13:41:43 -04:00
amdkfd drm/amdkfd: report the real PCI bus number 2020-05-21 12:48:42 -04:00
display drm/amd/display: Set/Reset avmute when disable/enable stream 2020-05-21 12:48:43 -04:00
include drm/amd/display: Add DC Debug mask to disable features for bringup 2020-05-21 12:37:19 -04:00
powerplay drm/amdgpu/smu10: Replace one-element array and use struct_size() helper 2020-05-21 12:48:43 -04:00