drm/format-helper: Add KUnit tests for drm_fb_xrgb8888_to_rgb888()

Extend the existing test cases to test the conversion from XRGB8888 to
RGB888.
Tested-by: Maíra Canal <mairacanal@riseup.net>
Reviewed-by: David Gow <davidgow@google.com>
Acked-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220926080837.65734-2-jose.exposito89@gmail.com

drivers/gpu/drm/tests/drm_format_helper_test.c

@@ -27,6 +27,11 @@ struct convert_to_rgb565_result {
 	const u16 expected_swab[TEST_BUF_SIZE];
 };
 
+struct convert_to_rgb888_result {
+	unsigned int dst_pitch;
+	const u8 expected[TEST_BUF_SIZE];
+};
+
 struct convert_xrgb8888_case {
 	const char *name;
 	unsigned int pitch;
@@ -34,6 +39,7 @@ struct convert_xrgb8888_case {
 	const u32 xrgb8888[TEST_BUF_SIZE];
 	struct convert_to_rgb332_result rgb332_result;
 	struct convert_to_rgb565_result rgb565_result;
+	struct convert_to_rgb888_result rgb888_result;
 };
 
 static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
@@ -51,6 +57,10 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
 			.expected = { 0xF800 },
 			.expected_swab = { 0x00F8 },
 		},
+		.rgb888_result = {
+			.dst_pitch = 0,
+			.expected = { 0x00, 0x00, 0xFF },
+		},
 	},
 	{
 		.name = "single_pixel_clip_rectangle",
@@ -69,6 +79,10 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
 			.expected = { 0xF800 },
 			.expected_swab = { 0x00F8 },
 		},
+		.rgb888_result = {
+			.dst_pitch = 0,
+			.expected = { 0x00, 0x00, 0xFF },
+		},
 	},
 	{
 		/* Well known colors: White, black, red, green, blue, magenta,
@@ -109,6 +123,15 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
 				0xE0FF, 0xFF07,
 			},
 		},
+		.rgb888_result = {
+			.dst_pitch = 0,
+			.expected = {
+				0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00,
+				0x00, 0x00, 0xFF, 0x00, 0xFF, 0x00,
+				0xFF, 0x00, 0x00, 0xFF, 0x00, 0xFF,
+				0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0x00,
+			},
+		},
 	},
 	{
 		/* Randomly picked colors. Full buffer within the clip area. */
@@ -141,6 +164,17 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
 				0x00A8, 0x8E6B, 0x330A, 0x0000, 0x0000,
 			},
 		},
+		.rgb888_result = {
+			.dst_pitch = 15,
+			.expected = {
+				0x9C, 0x44, 0x0E, 0x05, 0x4D, 0x11, 0x03, 0x03, 0xA8,
+				0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+				0x73, 0x70, 0x6C, 0x9C, 0x44, 0x0E, 0x05, 0x4D, 0x11,
+				0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+				0x03, 0x03, 0xA8, 0x73, 0x70, 0x6C, 0x9C, 0x44, 0x0E,
+				0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			},
+		},
 	},
 };
 
@@ -255,9 +289,40 @@ static void drm_test_fb_xrgb8888_to_rgb565(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, memcmp(buf, result->expected_swab, dst_size), 0);
 }
 
+static void drm_test_fb_xrgb8888_to_rgb888(struct kunit *test)
+{
+	const struct convert_xrgb8888_case *params = test->param_value;
+	const struct convert_to_rgb888_result *result = &params->rgb888_result;
+	size_t dst_size;
+	__u8 *buf = NULL;
+	__u32 *xrgb8888 = NULL;
+	struct iosys_map dst, src;
+
+	struct drm_framebuffer fb = {
+		.format = drm_format_info(DRM_FORMAT_XRGB8888),
+		.pitches = { params->pitch, 0, 0 },
+	};
+
+	dst_size = conversion_buf_size(DRM_FORMAT_RGB888, result->dst_pitch,
+				       &params->clip);
+	KUNIT_ASSERT_GT(test, dst_size, 0);
+
+	buf = kunit_kzalloc(test, dst_size, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf);
+	iosys_map_set_vaddr(&dst, buf);
+
+	xrgb8888 = le32buf_to_cpu(test, params->xrgb8888, TEST_BUF_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, xrgb8888);
+	iosys_map_set_vaddr(&src, xrgb8888);
+
+	drm_fb_xrgb8888_to_rgb888(&dst, &result->dst_pitch, &src, &fb, &params->clip);
+	KUNIT_EXPECT_EQ(test, memcmp(buf, result->expected, dst_size), 0);
+}
+
 static struct kunit_case drm_format_helper_test_cases[] = {
 	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_rgb332, convert_xrgb8888_gen_params),
 	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_rgb565, convert_xrgb8888_gen_params),
+	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_rgb888, convert_xrgb8888_gen_params),
 	{}
 };