drm/amdgpu: add comments in ras interrupt callback

add comments to clarify why checking GFX IP BLOCK for each ras interrupt callback
Signed-off-by: Tao Zhou <tao.zhou1@amd.com>
Reviewed-by: Guchun Chen <guchun.chen@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -636,7 +636,12 @@ int amdgpu_gfx_process_ras_data_cb(struct amdgpu_device *adev,
 		void *err_data,
 		struct amdgpu_iv_entry *entry)
 {
-	/* TODO ue will trigger an interrupt. */
+	/* TODO ue will trigger an interrupt.
+	 *
+	 * When “Full RAS” is enabled, the per-IP interrupt sources should
+	 * be disabled and the driver should only look for the aggregated
+	 * interrupt via sync flood
+	 */
 	if (!amdgpu_ras_is_supported(adev, AMDGPU_RAS_BLOCK__GFX)) {
 		kgd2kfd_set_sram_ecc_flag(adev->kfd.dev);
 		if (adev->gfx.funcs->query_ras_error_count)

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

@@ -95,6 +95,10 @@ int amdgpu_umc_process_ras_data_cb(struct amdgpu_device *adev,
 {
 	struct ras_err_data *err_data = (struct ras_err_data *)ras_error_status;
 
+	/* When “Full RAS” is enabled, the per-IP interrupt sources should
+	 * be disabled and the driver should only look for the aggregated
+	 * interrupt via sync flood
+	 */
 	if (amdgpu_ras_is_supported(adev, AMDGPU_RAS_BLOCK__GFX))
 		return AMDGPU_RAS_SUCCESS;
 

drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c

@@ -1930,6 +1930,10 @@ static int sdma_v4_0_process_ras_data_cb(struct amdgpu_device *adev,
 {
 	int instance;
 
+	/* When “Full RAS” is enabled, the per-IP interrupt sources should
+	 * be disabled and the driver should only look for the aggregated
+	 * interrupt via sync flood
+	 */
 	if (amdgpu_ras_is_supported(adev, AMDGPU_RAS_BLOCK__GFX))
 		goto out;