[PATCH v6 18/21] drm/tests: hdmi: Add tests for the color_format property

[Nicolas Frattaroli <nicolas.frattaroli@collabora.com>]

Add some KUnit tests to check the color_format property is working as
expected with the HDMI state helper.

Existing tests are extended to also test the DRM_COLOR_FORMAT_AUTO case,
in order to avoid duplicating test cases. For the explicitly selected
color format cases, parameterized tests are added.

Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 191 +++++++++++++++++++++
 1 file changed, 191 insertions(+)

diff --git a/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c b/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
index 4bdcea3c7435..f9648f9de46b 100644
--- a/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
+++ b/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
@@ -60,6 +60,23 @@ static struct drm_display_mode *find_preferred_mode(struct drm_connector *connec
 	return preferred;
 }
 
+static struct drm_display_mode *find_420_only_mode(struct drm_connector *connector)
+{
+	struct drm_device *drm = connector->dev;
+	struct drm_display_mode *mode;
+
+	mutex_lock(&drm->mode_config.mutex);
+	list_for_each_entry(mode, &connector->modes, head) {
+		if (drm_mode_is_420_only(&connector->display_info, mode)) {
+			mutex_unlock(&drm->mode_config.mutex);
+			return mode;
+		}
+	}
+	mutex_unlock(&drm->mode_config.mutex);
+
+	return NULL;
+}
+
 static int set_connector_edid(struct kunit *test, struct drm_connector *connector,
 			      const void *edid, size_t edid_len)
 {
@@ -1547,6 +1564,7 @@ static void drm_test_check_max_tmds_rate_bpc_fallback_yuv420(struct kunit *test)
  *   RGB/10bpc
  * - The chosen mode has a TMDS character rate lower than the display
  *   supports in YUV422/12bpc.
+ * - The HDMI connector state's color format property is unset (i.e. AUTO)
  *
  * Then we will prefer to keep the RGB format with a lower bpc over
  * picking YUV422.
@@ -1609,6 +1627,7 @@ static void drm_test_check_max_tmds_rate_bpc_fallback_ignore_yuv422(struct kunit
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
+	KUNIT_ASSERT_EQ(test, conn_state->color_format, DRM_COLOR_FORMAT_AUTO);
 
 	KUNIT_EXPECT_EQ(test, conn_state->hdmi.output_bpc, 10);
 	KUNIT_EXPECT_EQ(test, conn_state->hdmi.output_format, HDMI_COLORSPACE_RGB);
@@ -1626,6 +1645,7 @@ static void drm_test_check_max_tmds_rate_bpc_fallback_ignore_yuv422(struct kunit
  *   RGB/8bpc
  * - The chosen mode has a TMDS character rate lower than the display
  *   supports in YUV420/12bpc.
+ * - The HDMI connector state's color format property is unset (i.e. AUTO)
  *
  * Then we will prefer to keep the RGB format with a lower bpc over
  * picking YUV420.
@@ -1687,6 +1707,7 @@ static void drm_test_check_max_tmds_rate_bpc_fallback_ignore_yuv420(struct kunit
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
+	KUNIT_ASSERT_EQ(test, conn_state->color_format, DRM_COLOR_FORMAT_AUTO);
 
 	KUNIT_EXPECT_EQ(test, conn_state->hdmi.output_bpc, 8);
 	KUNIT_EXPECT_EQ(test, conn_state->hdmi.output_format, HDMI_COLORSPACE_RGB);
@@ -2198,6 +2219,172 @@ static void drm_test_check_disable_connector(struct kunit *test)
 	drm_modeset_acquire_fini(&ctx);
 }
 
+struct color_format_test_param {
+	enum drm_color_format fmt;
+	enum hdmi_colorspace expected;
+	int expected_ret;
+	const char *desc;
+};
+
+/* Test that if:
+ * - an HDMI connector supports RGB, YUV444, YUV422, and YUV420
+ * - the display supports RGB, YUV444, YUV422, and YUV420
+ * - the "color format" property is set
+ * then, for the preferred mode, for a given "color format" option:
+ * - DRM_COLOR_FORMAT_AUTO results in an HDMI output format of RGB
+ * - DRM_COLOR_FORMAT_YCBCR422 results in an HDMI output format of YUV422
+ * - DRM_COLOR_FORMAT_YCBCR420 results in an HDMI output format of YUV420
+ * - DRM_COLOR_FORMAT_YCBCR444 results in an HDMI output format of YUV444
+ * - DRM_COLOR_FORMAT_RGB results in an HDMI output format of RGB
+ */
+static void drm_test_check_hdmi_color_format(struct kunit *test)
+{
+	const struct color_format_test_param *param = test->param_value;
+	struct drm_atomic_helper_connector_hdmi_priv *priv;
+	struct drm_connector_state *conn_state;
+	struct drm_modeset_acquire_ctx ctx;
+	struct drm_crtc_state *crtc_state;
+	struct drm_atomic_state *state;
+	struct drm_display_info *info;
+	struct drm_display_mode *preferred;
+	int ret;
+
+	priv = drm_kunit_helper_connector_hdmi_init_with_edid_funcs(test,
+				BIT(HDMI_COLORSPACE_RGB) |
+				BIT(HDMI_COLORSPACE_YUV422) |
+				BIT(HDMI_COLORSPACE_YUV420) |
+				BIT(HDMI_COLORSPACE_YUV444),
+				12,
+				&dummy_connector_hdmi_funcs,
+				test_edid_hdmi_4k_rgb_yuv420_dc_max_340mhz);
+	KUNIT_ASSERT_NOT_NULL(test, priv);
+
+	drm_modeset_acquire_init(&ctx, 0);
+
+	KUNIT_ASSERT_TRUE(test, priv->connector.ycbcr_420_allowed);
+
+	info = &priv->connector.display_info;
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, info);
+	preferred = find_preferred_mode(&priv->connector);
+	KUNIT_ASSERT_TRUE(test, drm_mode_is_420(info, preferred));
+
+	state = drm_kunit_helper_atomic_state_alloc(test, &priv->drm, &ctx);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
+
+	conn_state = drm_atomic_get_connector_state(state, &priv->connector);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, conn_state);
+
+	conn_state->color_format = param->fmt;
+
+	ret = drm_atomic_set_crtc_for_connector(conn_state, priv->crtc);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	crtc_state = drm_atomic_get_crtc_state(state, priv->crtc);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, crtc_state);
+
+	ret = drm_atomic_set_mode_for_crtc(crtc_state, preferred);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	crtc_state->enable = true;
+	crtc_state->active = true;
+
+	ret = drm_atomic_check_only(state);
+	KUNIT_EXPECT_EQ(test, ret, param->expected_ret);
+	KUNIT_EXPECT_EQ(test, conn_state->hdmi.output_format, param->expected);
+
+	drm_modeset_drop_locks(&ctx);
+	drm_modeset_acquire_fini(&ctx);
+}
+
+static const struct color_format_test_param hdmi_color_format_params[] = {
+	{ DRM_COLOR_FORMAT_AUTO, HDMI_COLORSPACE_RGB, 0, "AUTO -> RGB" },
+	{ DRM_COLOR_FORMAT_YCBCR422, HDMI_COLORSPACE_YUV422, 0, "YCBCR422 -> YUV422" },
+	{ DRM_COLOR_FORMAT_YCBCR420, HDMI_COLORSPACE_YUV420, 0, "YCBCR420 -> YUV420" },
+	{ DRM_COLOR_FORMAT_YCBCR444, HDMI_COLORSPACE_YUV444, 0, "YCBCR444 -> YUV444" },
+	{ DRM_COLOR_FORMAT_RGB444, HDMI_COLORSPACE_RGB, 0, "RGB -> RGB" },
+};
+
+KUNIT_ARRAY_PARAM_DESC(check_hdmi_color_format, hdmi_color_format_params, desc);
+
+/* Test that if:
+ * - the HDMI connector supports RGB, YUV422, YUV420, and YUV444
+ * - the display has a YUV420-only mode
+ * - the "color format" property is explicitly set (i.e. !AUTO)
+ * then:
+ * - color format DRM_COLOR_FORMAT_RGB will fail drm_atomic_check_only for the
+ *   YUV420-only mode with -EINVAL
+ * - color format DRM_COLOR_FORMAT_YCBCR444 will fail drm_atomic_check_only for
+ *   the YUV420-only mode with -EINVAL
+ * - color format DRM_COLOR_FORMAT_YCBCR422 will fail drm_atomic_check_only for
+ *   the YUV420-only mode with -EINVAL
+ * - color format DRM_COLOR_FORMAT_YCBCR420 passes drm_atomic_check_only for
+ *   the YUV420-only mode
+ */
+static void drm_test_check_hdmi_color_format_420_only(struct kunit *test)
+{
+	const struct color_format_test_param *param = test->param_value;
+	struct drm_atomic_helper_connector_hdmi_priv *priv;
+	struct drm_connector_state *conn_state;
+	struct drm_modeset_acquire_ctx ctx;
+	struct drm_crtc_state *crtc_state;
+	struct drm_atomic_state *state;
+	struct drm_display_mode *dank;
+	int ret;
+
+	priv = drm_kunit_helper_connector_hdmi_init_with_edid_funcs(test,
+				BIT(HDMI_COLORSPACE_RGB) |
+				BIT(HDMI_COLORSPACE_YUV422) |
+				BIT(HDMI_COLORSPACE_YUV420) |
+				BIT(HDMI_COLORSPACE_YUV444),
+				12,
+				&dummy_connector_hdmi_funcs,
+				test_edid_hdmi_1080p_rgb_yuv_4k_yuv420_dc_max_200mhz);
+	KUNIT_ASSERT_NOT_NULL(test, priv);
+
+	drm_modeset_acquire_init(&ctx, 0);
+
+	dank = find_420_only_mode(&priv->connector);
+	KUNIT_ASSERT_NOT_NULL(test, dank);
+
+	state = drm_kunit_helper_atomic_state_alloc(test, &priv->drm, &ctx);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
+
+	conn_state = drm_atomic_get_connector_state(state, &priv->connector);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, conn_state);
+
+	conn_state->color_format = param->fmt;
+
+	ret = drm_atomic_set_crtc_for_connector(conn_state, priv->crtc);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	crtc_state = drm_atomic_get_crtc_state(state, priv->crtc);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, crtc_state);
+
+	ret = drm_atomic_set_mode_for_crtc(crtc_state, dank);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	crtc_state->enable = true;
+	crtc_state->active = true;
+
+	ret = drm_atomic_check_only(state);
+	KUNIT_EXPECT_EQ(test, ret, param->expected_ret);
+	if (!param->expected_ret)
+		KUNIT_EXPECT_EQ(test, conn_state->hdmi.output_format, param->expected);
+
+	drm_modeset_drop_locks(&ctx);
+	drm_modeset_acquire_fini(&ctx);
+};
+
+static const struct color_format_test_param hdmi_color_format_420_only_params[] = {
+	{ DRM_COLOR_FORMAT_RGB444, HDMI_COLORSPACE_RGB, -EINVAL, "RGB should fail" },
+	{ DRM_COLOR_FORMAT_YCBCR444, HDMI_COLORSPACE_YUV444, -EINVAL, "YUV444 should fail" },
+	{ DRM_COLOR_FORMAT_YCBCR422, HDMI_COLORSPACE_YUV422, -EINVAL, "YUV422 should fail" },
+	{ DRM_COLOR_FORMAT_YCBCR420, HDMI_COLORSPACE_YUV420, 0, "YUV420 should work" },
+};
+
+KUNIT_ARRAY_PARAM_DESC(check_hdmi_color_format_420_only,
+		       hdmi_color_format_420_only_params, desc);
+
 static struct kunit_case drm_atomic_helper_connector_hdmi_check_tests[] = {
 	KUNIT_CASE(drm_test_check_broadcast_rgb_auto_cea_mode),
 	KUNIT_CASE(drm_test_check_broadcast_rgb_auto_cea_mode_vic_1),
@@ -2227,6 +2414,10 @@ static struct kunit_case drm_atomic_helper_connector_hdmi_check_tests[] = {
 	KUNIT_CASE(drm_test_check_tmds_char_rate_rgb_8bpc),
 	KUNIT_CASE(drm_test_check_tmds_char_rate_rgb_10bpc),
 	KUNIT_CASE(drm_test_check_tmds_char_rate_rgb_12bpc),
+	KUNIT_CASE_PARAM(drm_test_check_hdmi_color_format,
+			 check_hdmi_color_format_gen_params),
+	KUNIT_CASE_PARAM(drm_test_check_hdmi_color_format_420_only,
+			 check_hdmi_color_format_420_only_gen_params),
 	/*
 	 * TODO: We should have tests to check that a change in the
 	 * format triggers a CRTC mode change just like we do for the

-- 
2.52.0