[igt-dev] [PATCH 2/2] [i-g-t] tests/kms_cursor_crc: Fix test intermittent failures on AMD gpu

[Hersen Wu <hersenxs.wu@amd.com>]

Wait for two more vblanks before reading crc on AMD gpu.

Without waiting for two vblanks, AMD cursor updates may not
synchronized to the same frame of pipe, crc generated may
not be reliable for both hw_test and sw_test. For sw_test,
igt_wait_for_vblank_count within cursor_disable only applies
to loop 0 test of test_crc_onscreen, test_crc_sliding,
test_crc_random. Add igt_wait_for_vblank_count for sw_test
for loop 1 and above tests for AMD gpu to avoid intermittent
failures.

Signed-off-by: Hersen Wu <hersenxs.wu@amd.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
---
 tests/kms_cursor_crc.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/tests/kms_cursor_crc.c b/tests/kms_cursor_crc.c
index ba29ff65d..e3259e147 100644
--- a/tests/kms_cursor_crc.c
+++ b/tests/kms_cursor_crc.c
@@ -276,6 +276,15 @@ static void do_single_test(data_t *data, int x, int y, bool hw_test,
 		restore_image(data, swbufidx, &((cursorarea){x, y, data->curw, data->curh}));
 		igt_plane_set_fb(data->primary, &data->primary_fb[swbufidx]);
 		igt_display_commit(display);
+
+		/* Wait for two more vblanks since cursor updates may not
+		 * synchronized to the same frame on AMD HW
+		 */
+		if (is_amdgpu_device(data->drm_fd))
+			igt_wait_for_vblank_count(data->drm_fd,
+				display->pipes[data->pipe].crtc_offset,
+				data->vblank_wait_count);
+
 		igt_pipe_crc_get_current(data->drm_fd, pipe_crc, &crc);
 		igt_assert_crc_equal(&crc, hwcrc);
 	}
@@ -1079,7 +1088,11 @@ igt_main_args("e", NULL, help_str, opt_handler, NULL)
 
 		igt_require_pipe_crc(data.drm_fd);
 
-		data.vblank_wait_count = is_msm_device(data.drm_fd) ? 2 : 1;
+		/* Wait for two more vblanks since cursor updates may not
+		 * synchronized to the same frame on AMD HW
+		 */
+		data.vblank_wait_count =
+			(is_msm_device(data.drm_fd) || is_amdgpu_device(data.drm_fd)) ? 2 : 1;
 	}
 
 	data.cursor_max_w = cursor_width;
-- 
2.25.1