[PATCH 2/3] drm/amdgpu/vcn: fix ref counting for ring based profile handling

[Alex Deucher]

Only increment the power profile on the first submission.
Since the decrement may end up being pushed out as new
submissions come in, we only need to increment it once.

Fixes: 1443dd3c67f6 ("drm/amd/pm: fix and simplify workload handling”)
Cc: Yang Wang <kevinyang.wang at amd.com>
Cc: Kenneth Feng <kenneth.feng at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
index 8d8b39e6d197a..1954e276799bb 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
@@ -451,17 +451,23 @@ void amdgpu_vcn_ring_begin_use(struct amdgpu_ring *ring)
 {
 	struct amdgpu_device *adev = ring->adev;
 	struct amdgpu_vcn_inst *vcn_inst = &adev->vcn.inst[ring->me];
+	unsigned int fences = 0, i;
 	int r = 0;
 
-	atomic_inc(&vcn_inst->total_submission_cnt);
+	for (i = 0; i < vcn_inst->num_enc_rings; ++i)
+		fences += amdgpu_fence_count_emitted(&vcn_inst->ring_enc[i]);
+	fences += amdgpu_fence_count_emitted(&vcn_inst->ring_dec);
 
-	if (!cancel_delayed_work_sync(&vcn_inst->idle_work)) {
+	if (!cancel_delayed_work_sync(&vcn_inst->idle_work) && !fences &&
+	    !atomic_read(&vcn_inst->total_submission_cnt)) {
 		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);
 	}
 
+	atomic_inc(&vcn_inst->total_submission_cnt);
+
 	mutex_lock(&vcn_inst->vcn_pg_lock);
 	vcn_inst->set_pg_state(vcn_inst, AMD_PG_STATE_UNGATE);
 
-- 
2.48.1