drm/amdgpu: toggle DF-Cstate when accessing UMC ras error related registers

On arcturus, DF-Cstate needs to be toggled off/on
before and after accessing UMC error counter and
error address registers, otherwise, clearing such
registers may fail.
Signed-off-by: Guchun Chen <guchun.chen@amd.com>
Reviewed-by: John Clements <John.Clements@amd.com>
Reviewed-by: Tao Zhou <tao.zhou1@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/umc_v6_1.c

@@ -186,6 +186,10 @@ static void umc_v6_1_query_ras_error_count(struct amdgpu_device *adev,
 	if (rsmu_umc_index_state)
 		umc_v6_1_disable_umc_index_mode(adev);
 
+	if ((adev->asic_type == CHIP_ARCTURUS) &&
+		amdgpu_dpm_set_df_cstate(adev, DF_CSTATE_DISALLOW))
+		DRM_WARN("Fail to disable DF-Cstate.\n");
+
 	LOOP_UMC_INST_AND_CH(umc_inst, ch_inst) {
 		umc_reg_offset = get_umc_6_reg_offset(adev,
 						      umc_inst,
@@ -199,6 +203,10 @@ static void umc_v6_1_query_ras_error_count(struct amdgpu_device *adev,
 							  &(err_data->ue_count));
 	}
 
+	if ((adev->asic_type == CHIP_ARCTURUS) &&
+		amdgpu_dpm_set_df_cstate(adev, DF_CSTATE_ALLOW))
+		DRM_WARN("Fail to enable DF-Cstate\n");
+
 	if (rsmu_umc_index_state)
 		umc_v6_1_enable_umc_index_mode(adev);
 }
@@ -288,6 +296,10 @@ static void umc_v6_1_query_ras_error_address(struct amdgpu_device *adev,
 	if (rsmu_umc_index_state)
 		umc_v6_1_disable_umc_index_mode(adev);
 
+	if ((adev->asic_type == CHIP_ARCTURUS) &&
+		amdgpu_dpm_set_df_cstate(adev, DF_CSTATE_DISALLOW))
+		DRM_WARN("Fail to disable DF-Cstate.\n");
+
 	LOOP_UMC_INST_AND_CH(umc_inst, ch_inst) {
 		umc_reg_offset = get_umc_6_reg_offset(adev,
 						      umc_inst,
@@ -300,6 +312,10 @@ static void umc_v6_1_query_ras_error_address(struct amdgpu_device *adev,
 					     umc_inst);
 	}
 
+	if ((adev->asic_type == CHIP_ARCTURUS) &&
+		amdgpu_dpm_set_df_cstate(adev, DF_CSTATE_ALLOW))
+		DRM_WARN("Fail to enable DF-Cstate\n");
+
 	if (rsmu_umc_index_state)
 		umc_v6_1_enable_umc_index_mode(adev);
 }