[igt-dev] [PATCH i-g-t] tests/kms_plane_alpha_blend: Skip crc in coverage-vs-premult-vs-none for 6bpc panels

[Vidya Srinivas]

Intel Gen11 6bpc panels are giving CRC mismatch in coverage-vs-premult-vs-none
6bpc panel has dithering ON and CRC test with dithering ON might result in
mismatch. Hence, skipping CRC assertion for 6bpc panels.

Credits-to: Uma Shankar <uma.shankar at intel.com>
Credits-to: Juha-pekka Heikkila <juha-pekka.heikkila at intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas at intel.com>
---
 tests/kms_plane_alpha_blend.c | 39 +++++++++++++++++++++++++++++++++--
 1 file changed, 37 insertions(+), 2 deletions(-)

diff --git a/tests/kms_plane_alpha_blend.c b/tests/kms_plane_alpha_blend.c
index a37cb27c7d62..536d96546608 100644
--- a/tests/kms_plane_alpha_blend.c
+++ b/tests/kms_plane_alpha_blend.c
@@ -25,6 +25,7 @@
  */
 
 #include "igt.h"
+#include <string.h>
 
 IGT_TEST_DESCRIPTION("Test plane alpha and blending mode properties");
 
@@ -442,10 +443,41 @@ static void coverage_7efc(data_t *data, enum pipe pipe, igt_plane_t *plane)
 	igt_pipe_crc_stop(data->pipe_crc);
 }
 
+static bool is_6bpc(igt_display_t *display, enum pipe pipe) {
+	char buf[4096];
+	char *str;
+	bool ret;
+	int debugfs_fd;
+	igt_output_t *output = igt_get_single_output_for_pipe(display, pipe);
+
+	if (!is_i915_device(display->drm_fd))
+		return false;
+
+	drmModeConnector *c = output->config.connector;
+	if (c->connector_type != DRM_MODE_CONNECTOR_eDP)
+		return false;
+
+	debugfs_fd = igt_debugfs_dir(display->drm_fd);
+	if (debugfs_fd < 0)
+		return false;
+
+	igt_debugfs_simple_read(debugfs_fd, "i915_display_info", buf, sizeof(buf));
+
+	str = strstr(buf, "bpp=");
+	if (str && (strncmp(str, "bpp=18", 6) == 0))
+		ret = true;
+	else
+		ret = false;
+
+	close(debugfs_fd);
+	return ret;
+}
+
 static void coverage_premult_constant(data_t *data, enum pipe pipe, igt_plane_t *plane)
 {
 	igt_display_t *display = &data->display;
 	igt_crc_t ref_crc = {}, crc = {};
+	bool is6bpc;
 
 	/* Set a background color on the primary fb for testing */
 	if (plane->type != DRM_PLANE_TYPE_PRIMARY)
@@ -461,14 +493,17 @@ static void coverage_premult_constant(data_t *data, enum pipe pipe, igt_plane_t
 	igt_plane_set_fb(plane, &data->argb_fb_7e);
 	igt_display_commit2(display, COMMIT_ATOMIC);
 	igt_pipe_crc_get_current(display->drm_fd, data->pipe_crc, &crc);
-	igt_assert_crc_equal(&ref_crc, &crc);
+
+	if (is_6bpc(display, pipe) == false)
+		igt_assert_crc_equal(&ref_crc, &crc);
 
 	igt_plane_set_prop_enum(plane, IGT_PLANE_PIXEL_BLEND_MODE, "None");
 	igt_plane_set_prop_value(plane, IGT_PLANE_ALPHA, 0x7e7e);
 	igt_plane_set_fb(plane, &data->argb_fb_cov_7e);
 	igt_display_commit2(display, COMMIT_ATOMIC);
 	igt_pipe_crc_get_current(display->drm_fd, data->pipe_crc, &crc);
-	igt_assert_crc_equal(&ref_crc, &crc);
+	if (is_6bpc(display, pipe) == false)
+		igt_assert_crc_equal(&ref_crc, &crc);
 
 	igt_pipe_crc_stop(data->pipe_crc);
 }
-- 
2.32.0