There is a race condition which leads to dpm video power
profile switch (disable and enable) during active video
decode on multi-instance VCN hardware.

This patch aims to fix/skip step 3 in the below sequence:

 - inst_1       power_on
 - inst_0(idle) power_off
 - inst_0(idle) video_power_profile OFF (step 3)
 - inst_1       video_power_profile ON during next begin_use

Add flags to track ON/OFF vcn instances and check if all
instances are off before disabling video power profile.

Protect workload_profile_active also within pg_lock and ON it
during first use and OFF it when last VCN instance is powered
OFF. VCN workload_profile_mutex can be removed after similar
clean up is done for vcn2_5.

Signed-off-by: Sathishkumar S <sathishkumar.sundarar...@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c | 24 +++++++++---------------
 drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.h |  4 ++++
 2 files changed, 13 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
index 9a76e11d1c18..da372dd7b761 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
@@ -445,16 +445,16 @@ static void amdgpu_vcn_idle_work_handler(struct 
work_struct *work)
        if (!fences && !atomic_read(&vcn_inst->total_submission_cnt)) {
                mutex_lock(&vcn_inst->vcn_pg_lock);
                vcn_inst->set_pg_state(vcn_inst, AMD_PG_STATE_GATE);
-               mutex_unlock(&vcn_inst->vcn_pg_lock);
-               mutex_lock(&adev->vcn.workload_profile_mutex);
-               if (adev->vcn.workload_profile_active) {
+               adev->vcn.flags &= AMDGPU_VCN_FLAG_VINST_OFF(vcn_inst->inst);
+               if (adev->vcn.workload_profile_active &&
+                   !(adev->vcn.flags & 
AMDGPU_VCN_FLAG_VINST_MASK(adev->vcn.num_vcn_inst))) {
                        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);
+               mutex_unlock(&vcn_inst->vcn_pg_lock);
        } else {
                schedule_delayed_work(&vcn_inst->idle_work, VCN_IDLE_TIMEOUT);
        }
@@ -470,14 +470,8 @@ void amdgpu_vcn_ring_begin_use(struct amdgpu_ring *ring)
 
        cancel_delayed_work_sync(&vcn_inst->idle_work);
 
-       /* We can safely return early here because we've cancelled the
-        * the delayed work so there is no one else to set it to false
-        * and we don't care if someone else sets it to true.
-        */
-       if (adev->vcn.workload_profile_active)
-               goto pg_lock;
+       mutex_lock(&vcn_inst->vcn_pg_lock);
 
-       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);
@@ -485,11 +479,11 @@ void amdgpu_vcn_ring_begin_use(struct amdgpu_ring *ring)
                        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);
 
-pg_lock:
-       mutex_lock(&vcn_inst->vcn_pg_lock);
-       vcn_inst->set_pg_state(vcn_inst, AMD_PG_STATE_UNGATE);
+       if (!(adev->vcn.flags & AMDGPU_VCN_FLAG_VINST_ON(vcn_inst->inst))) {
+               vcn_inst->set_pg_state(vcn_inst, AMD_PG_STATE_UNGATE);
+               adev->vcn.flags |= AMDGPU_VCN_FLAG_VINST_ON(vcn_inst->inst);
+       }
 
        /* Only set DPG pause for VCN3 or below, VCN4 and above will be handled 
by FW */
        if (adev->pg_flags & AMD_PG_SUPPORT_VCN_DPG &&
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.h 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.h
index b3fb1d0e43fc..a876a182ff88 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.h
@@ -366,6 +366,10 @@ struct amdgpu_vcn {
        struct mutex            workload_profile_mutex;
        u32 reg_count;
        const struct amdgpu_hwip_reg_entry *reg_list;
+#define AMDGPU_VCN_FLAG_VINST_MASK(n)  (BIT(n+1) - 1)
+#define AMDGPU_VCN_FLAG_VINST_ON(n)    (BIT(n))
+#define AMDGPU_VCN_FLAG_VINST_OFF(n)   (~BIT(n))
+       u32 flags;
 };
 
 struct amdgpu_fw_shared_rb_ptrs_struct {
-- 
2.48.1

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