drm/amdgpu: enable DPG mode for VCN3.0

Enable DPG mode for VCN3.0 by updating related flag.

V2: update description.
Signed-off-by: Boyuan Zhang <boyuan.zhang@amd.com>
Reviewed-by: James Zhu <james.zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/nv.c

@@ -726,6 +726,7 @@ static int nv_common_early_init(void *handle)
 			AMD_CG_SUPPORT_IH_CG |
 			AMD_CG_SUPPORT_MC_LS;
 		adev->pg_flags = AMD_PG_SUPPORT_VCN |
+			AMD_PG_SUPPORT_VCN_DPG |
 			AMD_PG_SUPPORT_JPEG |
 			AMD_PG_SUPPORT_ATHUB;
 		adev->external_rev_id = adev->rev_id + 0x28;

drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c

@@ -254,7 +254,8 @@ static int vcn_v3_0_hw_init(void *handle)
 
 done:
 	if (!r)
-		DRM_INFO("VCN decode and encode initialized successfully.\n");
+		DRM_INFO("VCN decode and encode initialized successfully(under %s).\n",
+			(adev->pg_flags & AMD_PG_SUPPORT_VCN_DPG)?"DPG Mode":"SPG Mode");
 
 	return r;
 }
@@ -278,7 +279,9 @@ static int vcn_v3_0_hw_fini(void *handle)
 
 		ring = &adev->vcn.inst[i].ring_dec;
 
-		if (RREG32_SOC15(VCN, i, mmUVD_STATUS))
+		if ((adev->pg_flags & AMD_PG_SUPPORT_VCN_DPG) ||
+			(adev->vcn.cur_state != AMD_PG_STATE_GATE &&
+			RREG32_SOC15(VCN, i, mmUVD_STATUS)))
 			vcn_v3_0_set_powergating_state(adev, AMD_PG_STATE_GATE);
 
 		ring->sched.ready = false;