drm/amd: Add detailed GFXOFF stats to debugfs

Add debugfs interface to log GFXOFF statistics:

- Read amdgpu_gfxoff_count to get the total GFXOFF entry count at the
  time of query since system power-up

- Write 1 to amdgpu_gfxoff_residency to start logging, and 0 to stop.
  Read it to get average GFXOFF residency % multiplied by 100
  during the last logging interval.

Both features are designed to be keep the values persistent between
suspends.

Signed-off-by: André Almeida <andrealmeid@igalia.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index c84fdef0ac45..9cb6340c0247 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -3577,6 +3577,8 @@ int amdgpu_device_init(struct amdgpu_device *adev,
 	INIT_WORK(&adev->xgmi_reset_work, amdgpu_device_xgmi_reset_func);
 
 	adev->gfx.gfx_off_req_count = 1;
+	adev->gfx.gfx_off_residency = 0;
+	adev->gfx.gfx_off_entrycount = 0;
 	adev->pm.ac_power = power_supply_is_system_supplied() > 0;
 
 	atomic_set(&adev->throttling_logging_enabled, 1);