[igt-dev] [PATCH i-g-t 02/17] tests/kms_dither: Validate dither after CC blocks

@@ -57,7 +57,8 @@ typedef struct data {
 
 typedef struct {
 	unsigned int bpc;
-	unsigned int dither;
+	unsigned int legacy;
+	unsigned int cc1;
 } dither_status_t;
 
 /* Prepare test data. */

@@ -104,7 +105,13 @@ static dither_status_t get_dither_state(data_t *data)
 	igt_assert_eq(sscanf(start_loc, "bpc: %u", &status.bpc), 1);
 
 	igt_assert(start_loc = strstr(buf, "Dither: "));
-	igt_assert_eq(sscanf(start_loc, "Dither: %u", &status.dither), 1);
+	igt_assert_eq(sscanf(start_loc, "Dither: %u", &status.legacy), 1);
+
+	start_loc = strstr(buf, "Dither_CC1: ");
+	if (!start_loc)
+		status.cc1 = 0;
+	else
+		igt_assert_eq(sscanf(start_loc, "Dither_CC1: %u", &status.cc1), 1);
 
 	return status;
 }

@@ -141,10 +148,10 @@ static void test_dithering(data_t *data, enum pipe pipe,
 	 */
 	status = get_dither_state(data);
 
-	igt_debug("FB BPC:%d, Panel BPC:%d, Pipe BPC:%d, Expected Dither:%s, Actual result:%s\n",
-		  fb_bpc, output_bpc, status.bpc,
-		  (fb_bpc > output_bpc) ? "Enable": "Disable",
-		  status.dither ? "Enable": "Disable");
+	igt_debug("FB BPC:%d, Panel BPC:%d, Pipe BPC:%d, "
+		  "Dither at end of the pipe:%u, Dither after CC1:%u\n",
+			fb_bpc, output_bpc, status.bpc,
+			status.legacy, status.cc1);
 
        /*
 	* We must update the Connector max_bpc property back

@@ -163,12 +170,25 @@ static void test_dithering(data_t *data, enum pipe pipe,
 				output->name, status.bpc, output_bpc);
 
 	/* Compute the result. */
-	if (fb_bpc > output_bpc)
-		igt_assert_f(status.dither, "(fb_%dbpc > output_%dbpc): Dither should be enabled\n",
-				fb_bpc, output_bpc);
-	else
-		igt_assert_f(!status.dither, "(fb_%dbpc <= output_%dbpc): Dither should be disabled\n",
+	if (fb_bpc > output_bpc) {
+		if (output_bpc < IGT_CONNECTOR_BPC_12)
+			igt_assert_f((status.legacy && !status.cc1),
+					"(fb_%dbpc > output_%dbpc): Dither should be "
+					"enabled at end of the PIPE & "
+					"disbaled at the CC1.\n",
+					fb_bpc, output_bpc);
+		else
+			igt_assert_f((!status.legacy && status.cc1),
+					"(fb_%dbpc > output_%dbpc): Dither should be "
+					"disabled at end of the PIPE & "
+					"enabled at the CC1.\n",
+					fb_bpc, output_bpc);
+	} else {
+		igt_assert_f((!status.legacy && !status.cc1),
+				"(fb_%dbpc <= output_%dbpc): Dither should be "
+				"disabled at both places (end of the PIPE & CC1).\n",
 				fb_bpc, output_bpc);
+	}
 
 	return;
 }

@@ -218,6 +238,7 @@ igt_main
 	} tests[] = {
 		{ IGT_FRAME_BUFFER_BPC_8, DRM_FORMAT_XRGB8888, IGT_CONNECTOR_BPC_6 },
 		{ IGT_FRAME_BUFFER_BPC_8, DRM_FORMAT_XRGB8888, IGT_CONNECTOR_BPC_8 },
+		{ IGT_FRAME_BUFFER_BPC_16, DRM_FORMAT_XRGB16161616F, IGT_CONNECTOR_BPC_12 },
 	};
 	int i;
 	data_t data = { 0 };