drm/amdgpu: refine uvd_4.2 clock gate sequence.

1. partial revert commit 91db308d6e96.
   not set uvd bypass mode.
2. enable uvd cg before initialize uvd.
3. set uvd clock to default value 100MHz.
Signed-off-by: Rex Zhu <Rex.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/ci_dpm.c

@@ -4202,11 +4202,6 @@ static int ci_update_uvd_dpm(struct amdgpu_device *adev, bool gate)
 
 	if (!gate) {
 		/* turn the clocks on when decoding */
-		ret = amdgpu_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
-						    AMD_CG_STATE_UNGATE);
-		if (ret)
-			return ret;
-
 		if (pi->caps_uvd_dpm ||
 		    (adev->pm.dpm.dyn_state.uvd_clock_voltage_dependency_table.count <= 0))
 			pi->smc_state_table.UvdBootLevel = 0;
@@ -4223,9 +4218,6 @@ static int ci_update_uvd_dpm(struct amdgpu_device *adev, bool gate)
 		ret = ci_enable_uvd_dpm(adev, false);
 		if (ret)
 			return ret;
-
-		ret = amdgpu_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
-						    AMD_CG_STATE_GATE);
 	}
 
 	return ret;

drivers/gpu/drm/amd/amdgpu/uvd_v4_2.c

@@ -45,7 +45,8 @@ static void uvd_v4_2_set_ring_funcs(struct amdgpu_device *adev);
 static void uvd_v4_2_set_irq_funcs(struct amdgpu_device *adev);
 static int uvd_v4_2_start(struct amdgpu_device *adev);
 static void uvd_v4_2_stop(struct amdgpu_device *adev);
-
+static int uvd_v4_2_set_clockgating_state(void *handle,
+				enum amd_clockgating_state state);
 /**
  * uvd_v4_2_ring_get_rptr - get read pointer
  *
@@ -154,9 +155,9 @@ static int uvd_v4_2_hw_init(void *handle)
 	uint32_t tmp;
 	int r;
 
-	/* raise clocks while booting up the VCPU */
-	amdgpu_asic_set_uvd_clocks(adev, 53300, 40000);
-
+	uvd_v4_2_init_cg(adev);
+	uvd_v4_2_set_clockgating_state(adev, AMD_CG_STATE_GATE);
+	amdgpu_asic_set_uvd_clocks(adev, 10000, 10000);
 	r = uvd_v4_2_start(adev);
 	if (r)
 		goto done;
@@ -196,8 +197,6 @@ static int uvd_v4_2_hw_init(void *handle)
 	amdgpu_ring_commit(ring);
 
 done:
-	/* lower clocks again */
-	amdgpu_asic_set_uvd_clocks(adev, 0, 0);
 
 	if (!r)
 		DRM_INFO("UVD initialized successfully.\n");
@@ -274,9 +273,6 @@ static int uvd_v4_2_start(struct amdgpu_device *adev)
 
 	uvd_v4_2_mc_resume(adev);
 
-	/* disable clock gating */
-	WREG32(mmUVD_CGC_GATE, 0);
-
 	/* disable interupt */
 	WREG32_P(mmUVD_MASTINT_EN, 0, ~(1 << 1));
 
@@ -568,8 +564,6 @@ static void uvd_v4_2_mc_resume(struct amdgpu_device *adev)
 	WREG32(mmUVD_UDEC_ADDR_CONFIG, adev->gfx.config.gb_addr_config);
 	WREG32(mmUVD_UDEC_DB_ADDR_CONFIG, adev->gfx.config.gb_addr_config);
 	WREG32(mmUVD_UDEC_DBW_ADDR_CONFIG, adev->gfx.config.gb_addr_config);
-
-	uvd_v4_2_init_cg(adev);
 }
 
 static void uvd_v4_2_enable_mgcg(struct amdgpu_device *adev,
@@ -579,7 +573,7 @@ static void uvd_v4_2_enable_mgcg(struct amdgpu_device *adev,
 
 	if (enable && (adev->cg_flags & AMD_CG_SUPPORT_UVD_MGCG)) {
 		data = RREG32_UVD_CTX(ixUVD_CGC_MEM_CTRL);
-		data = 0xfff;
+		data |= 0xfff;
 		WREG32_UVD_CTX(ixUVD_CGC_MEM_CTRL, data);
 
 		orig = data = RREG32(mmUVD_CGC_CTRL);
@@ -686,34 +680,18 @@ static int uvd_v4_2_process_interrupt(struct amdgpu_device *adev,
 	return 0;
 }
 
-static void uvd_v5_0_set_bypass_mode(struct amdgpu_device *adev, bool enable)
-{
-	u32 tmp = RREG32_SMC(ixGCK_DFS_BYPASS_CNTL);
-
-	if (enable)
-		tmp |= (GCK_DFS_BYPASS_CNTL__BYPASSDCLK_MASK |
-			GCK_DFS_BYPASS_CNTL__BYPASSVCLK_MASK);
-	else
-		tmp &= ~(GCK_DFS_BYPASS_CNTL__BYPASSDCLK_MASK |
-			 GCK_DFS_BYPASS_CNTL__BYPASSVCLK_MASK);
-
-	WREG32_SMC(ixGCK_DFS_BYPASS_CNTL, tmp);
-}
-
 static int uvd_v4_2_set_clockgating_state(void *handle,
 					  enum amd_clockgating_state state)
 {
 	bool gate = false;
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 
-	if (state == AMD_CG_STATE_GATE)
-		gate = true;
-
-	uvd_v5_0_set_bypass_mode(adev, gate);
-
 	if (!(adev->cg_flags & AMD_CG_SUPPORT_UVD_MGCG))
 		return 0;
 
+	if (state == AMD_CG_STATE_GATE)
+		gate = true;
+
 	uvd_v4_2_enable_mgcg(adev, gate);
 
 	return 0;