[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" stateļ¼Œthen 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.g...@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
index 17bc7f5..d45394c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
@@ -371,6 +371,15 @@ static ssize_t 
amdgpu_set_power_dpm_force_performance_level(struct device *dev,
                return count;
        }
 
+       if(adev->asic_type == CHIP_RAVEN){
+               if (adev->rev_id < 8){
+                       if (current_level != AMD_DPM_FORCED_LEVEL_MANUAL && 
level == AMD_DPM_FORCED_LEVEL_MANUAL)
+                               amdgpu_gfx_off_ctrl(adev, false);
+                       else if (current_level == AMD_DPM_FORCED_LEVEL_MANUAL 
&& level != AMD_DPM_FORCED_LEVEL_MANUAL)
+                               amdgpu_gfx_off_ctrl(adev, true);
+               }
+       }
+
        /* profile_exit setting is valid only when current mode is in profile 
mode */
        if (!(current_level & (AMD_DPM_FORCED_LEVEL_PROFILE_STANDARD |
            AMD_DPM_FORCED_LEVEL_PROFILE_MIN_SCLK |
-- 
2.7.4

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