[igt-dev] [PATCH i-g-t v4 4/6] kms_writeback: Add writeback-check-output

[Brian Starkey]

Hi,

On Mon, Nov 05, 2018 at 10:16:14AM +0000, Liviu Dudau wrote:
>From: Brian Starkey <brian.starkey at arm.com>
>
>Add a test which makes commits using the writeback connector, and
>checks the output buffer hash to make sure it is/isn't written as
>appropriate.
>
>Signed-off-by: Brian Starkey <brian.starkey at arm.com>
>[rebased and addressed comments from Maarten]
>Signed-off-by: Liviu Dudau <liviu.dudau at arm.com>
>
>---
> tests/kms_writeback.c | 127 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 127 insertions(+)
>
>diff --git a/tests/kms_writeback.c b/tests/kms_writeback.c
>index 636777d0b..7cb65207e 100644
>--- a/tests/kms_writeback.c
>+++ b/tests/kms_writeback.c
>@@ -30,6 +30,7 @@
> #include "igt.h"
> #include "igt_core.h"
> #include "igt_fb.h"
>+#include "sw_sync.h"
>
> static drmModePropertyBlobRes *get_writeback_formats_blob(igt_output_t *output)
> {
>@@ -221,6 +222,119 @@ static void writeback_fb_id(igt_output_t *output, igt_fb_t *valid_fb, igt_fb_t *
> 	igt_assert(ret == 0);
> }
>
>+static void fill_fb(igt_fb_t *fb, double color[3])
>+{
>+	cairo_t *cr = igt_get_cairo_ctx(fb->fd, fb);
>+	igt_assert(cr);
>+
>+	igt_paint_color(cr, 0, 0, fb->width, fb->height,
>+			color[0], color[1], color[2]);
>+}
>+
>+static void get_and_wait_out_fence(igt_output_t *output)
>+{
>+	int ret;
>+
>+	igt_assert(output->writeback_out_fence_fd >= 0);
>+
>+	ret = sync_fence_wait(output->writeback_out_fence_fd, 1000);
>+	igt_assert(ret == 0);
>+	close(output->writeback_out_fence_fd);

Setting to -1 could be helpful here too. Tracking down double-closed
fds is always a pain.

>+}
>+
>+static void writeback_sequence(igt_output_t *output, igt_plane_t *plane,
>+				igt_fb_t *in_fb, igt_fb_t *out_fbs[], int n_commits)
>+{
>+	int i, color_idx = 0;
>+	double in_fb_colors[2][3] = {
>+		{ 1.0, 0.0, 0.0 },
>+		{ 0.0, 1.0, 0.0 },
>+	};
>+	double clear_color[3] = { 1.0, 1.0, 1.0 };
>+	igt_crc_t cleared_crc, out_expected;
>+
>+	for (i = 0; i < n_commits; i++, color_idx++) {
>+		/* Change the input color each time */
>+		fill_fb(in_fb, in_fb_colors[color_idx % 2]);
>+
>+		if (out_fbs[i]) {
>+			igt_crc_t out_before;
>+
>+			/* Get the expected CRC */
>+			fill_fb(out_fbs[i], in_fb_colors[color_idx % 2]);
>+			igt_fb_get_crc(out_fbs[i], &out_expected);
>+
>+			fill_fb(out_fbs[i], clear_color);
>+			if (i == 0)
>+				igt_fb_get_crc(out_fbs[i], &cleared_crc);
>+			igt_fb_get_crc(out_fbs[i], &out_before);
>+			igt_assert_crc_equal(&cleared_crc, &out_before);
>+		}
>+
>+		/* Commit */
>+		igt_plane_set_fb(plane, in_fb);
>+		if (out_fbs[i])
>+			igt_output_set_writeback_fb(output, out_fbs[i]);
>+		else
>+			/* avoid setting the out fence ptr that is done via igt_output_set_writeback_fb() */
>+			igt_output_set_prop_value(output, IGT_CONNECTOR_WRITEBACK_FB_ID, 0);

Would it work to put this check in igt_output_set_writeback_fb() so
that it only requests an out-fence if fb_id != 0 ?

Cheers,
-Brian

>+
>+		igt_display_commit_atomic(output->display,
>+					  DRM_MODE_ATOMIC_ALLOW_MODESET,
>+					  NULL);
>+		if (out_fbs[i])
>+			get_and_wait_out_fence(output);
>+
>+		/* Make sure the old output buffer is untouched */
>+		if (i > 0 && out_fbs[i - 1] && (out_fbs[i] != out_fbs[i - 1])) {
>+			igt_crc_t out_prev;
>+			igt_fb_get_crc(out_fbs[i - 1], &out_prev);
>+			igt_assert_crc_equal(&cleared_crc, &out_prev);
>+		}
>+
>+		/* Make sure this output buffer is written */
>+		if (out_fbs[i]) {
>+			igt_crc_t out_after;
>+			igt_fb_get_crc(out_fbs[i], &out_after);
>+			igt_assert_crc_equal(&out_expected, &out_after);
>+
>+			/* And clear it, for the next time */
>+			fill_fb(out_fbs[i], clear_color);
>+		}
>+	}
>+}
>+
>+static void writeback_check_output(igt_output_t *output, igt_plane_t *plane,
>+				   igt_fb_t *input_fb, igt_fb_t *output_fb)
>+{
>+	igt_fb_t *out_fbs[2] = { 0 };
>+	igt_fb_t second_out_fb;
>+	int ret;
>+
>+	/* One commit, with a writeback. */
>+	writeback_sequence(output, plane, input_fb, &output_fb, 1);
>+
>+	/* Two commits, the second with no writeback */
>+	out_fbs[0] = output_fb;
>+	writeback_sequence(output, plane, input_fb, out_fbs, 2);
>+
>+	/* Two commits, both with writeback */
>+	out_fbs[1] = output_fb;
>+	writeback_sequence(output, plane, input_fb, out_fbs, 2);
>+
>+	ret = igt_create_fb(output_fb->fd, output_fb->width, output_fb->height,
>+			    DRM_FORMAT_XRGB8888,
>+			    igt_fb_mod_to_tiling(0),
>+			    &second_out_fb);
>+	igt_require(ret > 0);
>+
>+	/* Two commits, with different writeback buffers */
>+	out_fbs[1] = &second_out_fb;
>+	writeback_sequence(output, plane, input_fb, out_fbs, 2);
>+
>+	igt_remove_fb(output_fb->fd, &second_out_fb);
>+}
>+
> igt_main
> {
> 	igt_display_t display;
>@@ -307,6 +421,19 @@ igt_main
> 		igt_remove_fb(display.drm_fd, &output_fb);
> 	}
>
>+	igt_subtest("writeback-check-output") {
>+		igt_fb_t output_fb;
>+		ret = igt_create_fb(display.drm_fd, mode.hdisplay, mode.vdisplay,
>+				    DRM_FORMAT_XRGB8888,
>+				    igt_fb_mod_to_tiling(0),
>+				    &output_fb);
>+		igt_require(ret > 0);
>+
>+		writeback_check_output(output, plane, &input_fb, &output_fb);
>+
>+		igt_remove_fb(display.drm_fd, &output_fb);
>+	}
>+
> 	igt_fixture {
> 		igt_remove_fb(display.drm_fd, &input_fb);
> 		igt_display_fini(&display);
>-- 
>2.19.1
>