drm/format-helper: Add conversion from XRGB8888 to 15-bit RGB555 formats

Add conversion from XRGB8888 to XRGB1555, ARGB1555 and RGBA5551, which
are the formats currently supported by the simplefb infrastructure. The
new helpers allow the output of XRGB8888 framebuffers to firmware
scanout buffers in one of the 15-bit formats.

v3:
	* use __le* for destination buffers (Jose, kernel test robot)
v2:
	* test 15-bit results with local endianness (Jose)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230102112927.26565-10-tzimmermann@suse.de

1 files changed, 189 insertions, 0 deletions

diff --git a/drivers/gpu/drm/tests/drm_format_helper_test.c b/drivers/gpu/drm/tests/drm_format_helper_test.c
index de3aa252e8eb..f71dc0fe08a1 100644
--- a/drivers/gpu/drm/tests/drm_format_helper_test.c
+++ b/drivers/gpu/drm/tests/drm_format_helper_test.c
@@ -32,6 +32,21 @@ struct convert_to_rgb565_result {
 	const u16 expected_swab[TEST_BUF_SIZE];
 };
 
+struct convert_to_xrgb1555_result {
+	unsigned int dst_pitch;
+	const u16 expected[TEST_BUF_SIZE];
+};
+
+struct convert_to_argb1555_result {
+	unsigned int dst_pitch;
+	const u16 expected[TEST_BUF_SIZE];
+};
+
+struct convert_to_rgba5551_result {
+	unsigned int dst_pitch;
+	const u16 expected[TEST_BUF_SIZE];
+};
+
 struct convert_to_rgb888_result {
 	unsigned int dst_pitch;
 	const u8 expected[TEST_BUF_SIZE];
@@ -60,6 +75,9 @@ struct convert_xrgb8888_case {
 	struct convert_to_gray8_result gray8_result;
 	struct convert_to_rgb332_result rgb332_result;
 	struct convert_to_rgb565_result rgb565_result;
+	struct convert_to_xrgb1555_result xrgb1555_result;
+	struct convert_to_argb1555_result argb1555_result;
+	struct convert_to_rgba5551_result rgba5551_result;
 	struct convert_to_rgb888_result rgb888_result;
 	struct convert_to_argb8888_result argb8888_result;
 	struct convert_to_xrgb2101010_result xrgb2101010_result;
@@ -85,6 +103,18 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
 			.expected = { 0xF800 },
 			.expected_swab = { 0x00F8 },
 		},
+		.xrgb1555_result = {
+			.dst_pitch = 0,
+			.expected = { 0x7C00 },
+		},
+		.argb1555_result = {
+			.dst_pitch = 0,
+			.expected = { 0xFC00 },
+		},
+		.rgba5551_result = {
+			.dst_pitch = 0,
+			.expected = { 0xF801 },
+		},
 		.rgb888_result = {
 			.dst_pitch = 0,
 			.expected = { 0x00, 0x00, 0xFF },
@@ -123,6 +153,18 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
 			.expected = { 0xF800 },
 			.expected_swab = { 0x00F8 },
 		},
+		.xrgb1555_result = {
+			.dst_pitch = 0,
+			.expected = { 0x7C00 },
+		},
+		.argb1555_result = {
+			.dst_pitch = 0,
+			.expected = { 0xFC00 },
+		},
+		.rgba5551_result = {
+			.dst_pitch = 0,
+			.expected = { 0xF801 },
+		},
 		.rgb888_result = {
 			.dst_pitch = 0,
 			.expected = { 0x00, 0x00, 0xFF },
@@ -188,6 +230,33 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
 				0xE0FF, 0xFF07,
 			},
 		},
+		.xrgb1555_result = {
+			.dst_pitch = 0,
+			.expected = {
+				0x7FFF, 0x0000,
+				0x7C00, 0x03E0,
+				0x001F, 0x7C1F,
+				0x7FE0, 0x03FF,
+			},
+		},
+		.argb1555_result = {
+			.dst_pitch = 0,
+			.expected = {
+				0xFFFF, 0x8000,
+				0xFC00, 0x83E0,
+				0x801F, 0xFC1F,
+				0xFFE0, 0x83FF,
+			},
+		},
+		.rgba5551_result = {
+			.dst_pitch = 0,
+			.expected = {
+				0xFFFF, 0x0001,
+				0xF801, 0x07C1,
+				0x003F, 0xF83F,
+				0xFFC1, 0x07FF,
+			},
+		},
 		.rgb888_result = {
 			.dst_pitch = 0,
 			.expected = {
@@ -264,6 +333,30 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
 				0x00A8, 0x8E6B, 0x330A, 0x0000, 0x0000,
 			},
 		},
+		.xrgb1555_result = {
+			.dst_pitch = 10,
+			.expected = {
+				0x0513, 0x0920, 0x5400, 0x0000, 0x0000,
+				0x35CE, 0x0513, 0x0920, 0x0000, 0x0000,
+				0x5400, 0x35CE, 0x0513, 0x0000, 0x0000,
+			},
+		},
+		.argb1555_result = {
+			.dst_pitch = 10,
+			.expected = {
+				0x8513, 0x8920, 0xD400, 0x0000, 0x0000,
+				0xB5CE, 0x8513, 0x8920, 0x0000, 0x0000,
+				0xD400, 0xB5CE, 0x8513, 0x0000, 0x0000,
+			},
+		},
+		.rgba5551_result = {
+			.dst_pitch = 10,
+			.expected = {
+				0x0A27, 0x1241, 0xA801, 0x0000, 0x0000,
+				0x6B9D, 0x0A27, 0x1241, 0x0000, 0x0000,
+				0xA801, 0x6B9D, 0x0A27, 0x0000, 0x0000,
+			},
+		},
 		.rgb888_result = {
 			.dst_pitch = 15,
 			.expected = {
@@ -476,6 +569,99 @@ 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_xrgb1555(struct kunit *test)
+{
+	const struct convert_xrgb8888_case *params = test->param_value;
+	const struct convert_to_xrgb1555_result *result = &params->xrgb1555_result;
+	size_t dst_size;
+	u16 *buf = NULL;
+	__le32 *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_XRGB1555, 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 = cpubuf_to_le32(test, params->xrgb8888, TEST_BUF_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, xrgb8888);
+	iosys_map_set_vaddr(&src, xrgb8888);
+
+	drm_fb_xrgb8888_to_xrgb1555(&dst, &result->dst_pitch, &src, &fb, &params->clip);
+	buf = le16buf_to_cpu(test, (__force const __le16 *)buf, dst_size / sizeof(__le16));
+	KUNIT_EXPECT_EQ(test, memcmp(buf, result->expected, dst_size), 0);
+}
+
+static void drm_test_fb_xrgb8888_to_argb1555(struct kunit *test)
+{
+	const struct convert_xrgb8888_case *params = test->param_value;
+	const struct convert_to_argb1555_result *result = &params->argb1555_result;
+	size_t dst_size;
+	u16 *buf = NULL;
+	__le32 *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_ARGB1555, 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 = cpubuf_to_le32(test, params->xrgb8888, TEST_BUF_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, xrgb8888);
+	iosys_map_set_vaddr(&src, xrgb8888);
+
+	drm_fb_xrgb8888_to_argb1555(&dst, &result->dst_pitch, &src, &fb, &params->clip);
+	buf = le16buf_to_cpu(test, (__force const __le16 *)buf, dst_size / sizeof(__le16));
+	KUNIT_EXPECT_EQ(test, memcmp(buf, result->expected, dst_size), 0);
+}
+
+static void drm_test_fb_xrgb8888_to_rgba5551(struct kunit *test)
+{
+	const struct convert_xrgb8888_case *params = test->param_value;
+	const struct convert_to_rgba5551_result *result = &params->rgba5551_result;
+	size_t dst_size;
+	u16 *buf = NULL;
+	__le32 *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_RGBA5551, 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 = cpubuf_to_le32(test, params->xrgb8888, TEST_BUF_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, xrgb8888);
+	iosys_map_set_vaddr(&src, xrgb8888);
+
+	drm_fb_xrgb8888_to_rgba5551(&dst, &result->dst_pitch, &src, &fb, &params->clip);
+	buf = le16buf_to_cpu(test, (__force const __le16 *)buf, dst_size / sizeof(__le16));
+	KUNIT_EXPECT_EQ(test, memcmp(buf, result->expected, dst_size), 0);
+}
+
 static void drm_test_fb_xrgb8888_to_rgb888(struct kunit *test)
 {
 	const struct convert_xrgb8888_case *params = test->param_value;
@@ -607,6 +793,9 @@ static struct kunit_case drm_format_helper_test_cases[] = {
 	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_gray8, convert_xrgb8888_gen_params),
 	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_xrgb1555, convert_xrgb8888_gen_params),
+	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_argb1555, convert_xrgb8888_gen_params),
+	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_rgba5551, convert_xrgb8888_gen_params),
 	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_rgb888, convert_xrgb8888_gen_params),
 	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_argb8888, convert_xrgb8888_gen_params),
 	KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_xrgb2101010, convert_xrgb8888_gen_params),