drm/amdgpu/vcn: fix ref counting for ring based profile handling

We need to make sure the workload profile ref counts are
balanced.  This isn't currently the case because we can
increment the count on submissions, but the decrement may
be delayed as work comes in.  Track when we enable the
workload profile so the references are balanced.

v2: switch to a mutex and active flag
v3: fix mutex init

Fixes: 1443dd3c67f6 ("drm/amd/pm: fix and simplify workload handling")
Cc: Yang Wang <kevinyang.wang@amd.com>
Cc: Kenneth Feng <kenneth.feng@amd.com>
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 18 insertions, 8 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
index 8d8b39e6d197..6b410e601bb6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
@@ -438,10 +438,15 @@ static void amdgpu_vcn_idle_work_handler(struct work_struct *work)
 
 	if (!fences && !atomic_read(&vcn_inst->total_submission_cnt)) {
 		vcn_inst->set_pg_state(vcn_inst, AMD_PG_STATE_GATE);
-		r = amdgpu_dpm_switch_power_profile(adev, PP_SMC_POWER_PROFILE_VIDEO,
-						    false);
-		if (r)
-			dev_warn(adev->dev, "(%d) failed to disable video power profile mode\n", r);
+		mutex_lock(&adev->vcn.workload_profile_mutex);
+		if (adev->vcn.workload_profile_active) {
+			r = amdgpu_dpm_switch_power_profile(adev, PP_SMC_POWER_PROFILE_VIDEO,
+							    false);
+			if (r)
+				dev_warn(adev->dev, "(%d) failed to disable video power profile mode\n", r);
+			adev->vcn.workload_profile_active = false;
+		}
+		mutex_unlock(&adev->vcn.workload_profile_mutex);
 	} else {
 		schedule_delayed_work(&vcn_inst->idle_work, VCN_IDLE_TIMEOUT);
 	}
@@ -456,10 +461,15 @@ void amdgpu_vcn_ring_begin_use(struct amdgpu_ring *ring)
 	atomic_inc(&vcn_inst->total_submission_cnt);
 
 	if (!cancel_delayed_work_sync(&vcn_inst->idle_work)) {
-		r = amdgpu_dpm_switch_power_profile(adev, PP_SMC_POWER_PROFILE_VIDEO,
-				true);
-		if (r)
-			dev_warn(adev->dev, "(%d) failed to switch to video power profile mode\n", r);
+		mutex_lock(&adev->vcn.workload_profile_mutex);
+		if (!adev->vcn.workload_profile_active) {
+			r = amdgpu_dpm_switch_power_profile(adev, PP_SMC_POWER_PROFILE_VIDEO,
+							    true);
+			if (r)
+				dev_warn(adev->dev, "(%d) failed to switch to video power profile mode\n", r);
+			adev->vcn.workload_profile_active = true;
+		}
+		mutex_unlock(&adev->vcn.workload_profile_mutex);
 	}
 
 	mutex_lock(&vcn_inst->vcn_pg_lock);