Re: [PATCH i-g-t 6/6] tests/kms_chamelium_color_pipeline: Add FIXED_MATRIX colorop tests

On 8/6/2026 5:33 PM, Swati Sharma wrote:
> Add Chamelium frame-capture equivalents of the FIXED_MATRIX colorop
> tests from kms_color_pipeline. Unlike the pipe-CRC variant, these
> validate the output using chamelium_frame_match_or_dump() with analog
> frame comparison, whose tolerance accommodates the small differences
> between the software color model and the hardware fixed-point matrix
> that a bit-exact pipe CRC cannot.
> 
> The SW reference framebuffer is computed by converting the YUV input
> through igt_fb_convert(), which internally applies igt_ycbcr_to_rgb_matrix(),
> matching the reference computation used in the pipe-CRC variant.
> 
> New subtests:
>   - plane-fixed-matrix-yuv-rgb-bt601
>   - plane-fixed-matrix-yuv-rgb-bt709
>   - plane-fixed-matrix-yuv-rgb-bt2020
>   - plane-fixed-matrix-yuv-rgb-bt601-lim
>   - plane-fixed-matrix-yuv-rgb-bt709-lim
>   - plane-fixed-matrix-yuv-rgb-bt2020-lim
>   - plane-fixed-matrix-yuv-rgb-bt601-lut1d
>   - plane-fixed-matrix-yuv-rgb-bt709-lut1d
>   - plane-fixed-matrix-yuv-rgb-bt2020-lut1d
>   - plane-fixed-matrix-yuv-rgb-bt601-lim-lut1d
>   - plane-fixed-matrix-yuv-rgb-bt709-lim-lut1d
>   - plane-fixed-matrix-yuv-rgb-bt2020-lim-lut1d
> 
> v2: -Naming changes (CSC_FF -> FIXED_MATRIX)
> v3: -Drop YCbCr limited to full and RGB709 to RGB2020 matrices
>       until we have non-IGT userspace that shows their use
>      -Rename subtests to yuv-rgb-btXXX with limited range variants
> 
> Assisted-by: Claude Opus 4.6
> Signed-off-by: Swati Sharma <[email protected]>
> ---
>   .../chamelium/kms_chamelium_color_pipeline.c  | 307 ++++++++++++++++++
>   1 file changed, 307 insertions(+)
> 
> diff --git a/tests/chamelium/kms_chamelium_color_pipeline.c b/tests/chamelium/kms_chamelium_color_pipeline.c
> index db6107221..63c5a3a3c 100644
> --- a/tests/chamelium/kms_chamelium_color_pipeline.c
> +++ b/tests/chamelium/kms_chamelium_color_pipeline.c
> @@ -34,6 +34,26 @@
>    * @lut3d-green-only:		3D LUT
>    */
>   
> +/**
> + * SUBTEST: plane-fixed-matrix-%s
> + * Description: Test FIXED_MATRIX colorop for color space conversion: %arg[1].
> + *
> + * arg[1]:
> + *
> + * @yuv-rgb-bt601:		YUV BT.601 full range to RGB BT.601
> + * @yuv-rgb-bt709:		YUV BT.709 full range to RGB BT.709
> + * @yuv-rgb-bt2020:		YUV BT.2020 full range to RGB BT.2020
> + * @yuv-rgb-bt601-lim:		YUV BT.601 limited range to RGB BT.601
> + * @yuv-rgb-bt709-lim:		YUV BT.709 limited range to RGB BT.709
> + * @yuv-rgb-bt2020-lim:		YUV BT.2020 limited range to RGB BT.2020
> + * @yuv-rgb-bt601-lut1d:	YUV BT.601 full range to RGB BT.601, then 1D LUT
> + * @yuv-rgb-bt709-lut1d:	YUV BT.709 full range to RGB BT.709, then 1D LUT
> + * @yuv-rgb-bt2020-lut1d:	YUV BT.2020 full range to RGB BT.2020, then 1D LUT
> + * @yuv-rgb-bt601-lim-lut1d:	YUV BT.601 limited range to RGB BT.601, then 1D LUT
> + * @yuv-rgb-bt709-lim-lut1d:	YUV BT.709 limited range to RGB BT.709, then 1D LUT
> + * @yuv-rgb-bt2020-lim-lut1d:	YUV BT.2020 limited range to RGB BT.2020, then 1D LUT
> + */
> +
>   IGT_TEST_DESCRIPTION("Test to validate DRM plane color pipeline using Chamelium frame capture instead of pipe CRC");
>   
>   static void test_cleanup(data_t *data)
> @@ -345,6 +365,290 @@ run_tests_for_plane(data_t *data)
>   	}
>   }
>   
> +static void
> +_test_plane_fixed_matrix_colorops(data_t *data,
> +				  igt_plane_t *plane,
> +				  const color_t *fb_colors,
> +				  kms_colorop_t *colorops[],
> +				  uint32_t input_format,
> +				  enum igt_color_encoding encoding,
> +				  enum igt_color_range range,
> +				  struct chamelium_port *port)
> +{
> +	igt_display_t *display = &data->display;
> +	drmModeModeInfo *mode = data->mode;
> +	igt_colorop_t *color_pipeline;
> +	struct igt_fb fb, fbref;
> +	struct chamelium_frame_dump *frame;
> +	bool ret;
> +
> +	color_pipeline = get_color_pipeline(display, plane, colorops);
> +	igt_skip_on(!color_pipeline);
> +
> +	/* Create HW input framebuffer (YUV or RGB) */
> +	igt_assert(igt_create_fb_with_bo_size(data->drm_fd,
> +					      mode->hdisplay,
> +					      mode->vdisplay,
> +					      input_format,
> +					      DRM_FORMAT_MOD_LINEAR,
> +					      encoding, range,
> +					      &fb, 0, 0));
> +
> +	/* Paint the input fb with test colors */
> +	paint_rectangles(data, mode, fb_colors, &fb);
> +
> +	/*
> +	 * Software reference: convert the input fb through igt_fb_convert()
> +	 * which internally applies igt_ycbcr_to_rgb_matrix(). This matches
> +	 * what the HW FIXED_MATRIX colorop should produce.
> +	 * Chamelium analog comparison tolerates HW vs SW rounding differences.
> +	 */
> +	igt_fb_convert(&fbref, &fb, DRM_FORMAT_XRGB8888, DRM_FORMAT_MOD_LINEAR);

Can we re-use the pattern of collecting SW reference just once per pipe?

> +
> +	/* Hardware path */
> +	set_color_pipeline(display, plane, colorops, color_pipeline);
> +
> +	igt_plane_set_fb(plane, &fb);
> +	igt_display_commit_atomic(&data->display, 0, NULL);
> +
> +	chamelium_port_wait_video_input_stable(data->chamelium, port, 5);
> +	chamelium_capture(data->chamelium, port, 0, 0, 0, 0, 1);
> +
> +	frame = chamelium_read_captured_frame(data->chamelium, 0);
> +
> +	ret = chamelium_frame_match_or_dump(data->chamelium, port, frame,
> +					    &fbref, CHAMELIUM_CHECK_ANALOG);
> +	igt_assert(ret);
> +

assert is a problem here too. In here it will also lead to the frame 
dump leaking.

> +	chamelium_destroy_frame_dump(frame);
> +
> +	/* Cleanup */
> +	set_color_pipeline_bypass(plane);
> +	reset_colorops(colorops);
> +	igt_plane_set_fb(plane, NULL);
> +	igt_display_commit_atomic(&data->display, 0, NULL);
> +
> +	igt_remove_fb(data->drm_fd, &fb);
> +	igt_remove_fb(data->drm_fd, &fbref);
> +}
> +
> +static void
> +test_plane_fixed_matrix_colorops(data_t *data, igt_crtc_t *crtc,
> +				 const color_t *fb_colors,
> +				 kms_colorop_t *colorops[],
> +				 uint32_t input_format,
> +				 enum igt_color_encoding encoding,
> +				 enum igt_color_range range,
> +				 int port_idx)
> +{
> +	int n_planes = crtc->n_planes;
> +	igt_output_t *output = data->output;
> +	igt_plane_t *plane;
> +
> +	for (int plane_id = 0; plane_id < n_planes; plane_id++) {
> +		plane = igt_output_get_plane(output, plane_id);
> +
> +		if (!igt_plane_has_prop(plane, IGT_PLANE_COLOR_PIPELINE))
> +			continue;
> +
> +		igt_dynamic_f("pipe-%s-plane-%u", kmstest_pipe_name(crtc->pipe), plane_id)
> +			_test_plane_fixed_matrix_colorops(data, plane,
> +							  fb_colors,
> +							  colorops, input_format,
> +							  encoding, range,
> +							  data->ports[port_idx]);
> +	}
> +}
> +
> +static void
> +run_tests_for_fixed_matrix(data_t *data)
> +{
> +	igt_crtc_t *crtc;
> +	igt_output_t *output = NULL;
> +	int port_idx = 0;
> +	static const color_t colors_rgb[] = {
> +		{ 1.0, 0.0, 0.0 },
> +		{ 0.0, 1.0, 0.0 },
> +		{ 0.0, 0.0, 1.0 },
> +	};
> +	kms_colorop_t lut1d_linear = {
> +		.type = KMS_COLOROP_CUSTOM_LUT1D,
> +		.name = "1D LUT (linear)",
> +		.lut1d = &igt_1dlut_linear,
> +		.transform = &igt_color_linear,
> +	};
> +	kms_colorop_t fixed_matrix_yuv601_rgb601 = {
> +		.type = KMS_COLOROP_FIXED_MATRIX,
> +		.name = "FIXED_MATRIX YUV601 to RGB601",
> +		.fixed_matrix_info = { .fixed_matrix = KMS_COLOROP_FIXED_MATRIX_YCBCR601_FULL_RGB },
> +	};
> +	kms_colorop_t fixed_matrix_yuv709_rgb709 = {
> +		.type = KMS_COLOROP_FIXED_MATRIX,
> +		.name = "FIXED_MATRIX YUV709 to RGB709",
> +		.fixed_matrix_info = { .fixed_matrix = KMS_COLOROP_FIXED_MATRIX_YCBCR709_FULL_RGB },
> +	};
> +	kms_colorop_t fixed_matrix_yuv2020_rgb2020 = {
> +		.type = KMS_COLOROP_FIXED_MATRIX,
> +		.name = "FIXED_MATRIX YUV2020 to RGB2020",
> +		.fixed_matrix_info = { .fixed_matrix = KMS_COLOROP_FIXED_MATRIX_YCBCR2020_NC_FULL_RGB },
> +	};
> +	kms_colorop_t fixed_matrix_yuv601_rgb601_lim = {
> +		.type = KMS_COLOROP_FIXED_MATRIX,
> +		.name = "FIXED_MATRIX YUV601 limited to RGB601",
> +		.fixed_matrix_info = { .fixed_matrix = KMS_COLOROP_FIXED_MATRIX_YCBCR601_LIMITED_RGB },
> +	};
> +	kms_colorop_t fixed_matrix_yuv709_rgb709_lim = {
> +		.type = KMS_COLOROP_FIXED_MATRIX,
> +		.name = "FIXED_MATRIX YUV709 limited to RGB709",
> +		.fixed_matrix_info = { .fixed_matrix = KMS_COLOROP_FIXED_MATRIX_YCBCR709_LIMITED_RGB },
> +	};
> +	kms_colorop_t fixed_matrix_yuv2020_rgb2020_lim = {
> +		.type = KMS_COLOROP_FIXED_MATRIX,
> +		.name = "FIXED_MATRIX YUV2020 limited to RGB2020",
> +		.fixed_matrix_info = { .fixed_matrix = KMS_COLOROP_FIXED_MATRIX_YCBCR2020_NC_LIMITED_RGB },
> +	};
> +
> +	struct {
> +		const char *name;
> +		const char *subtest_prefix;
> +		const color_t *fb_colors;
> +		kms_colorop_t *colorops[MAX_COLOROPS];
> +		uint32_t input_format;
> +		enum igt_color_encoding encoding;
> +		enum igt_color_range range;
> +	} fixed_matrix_tests[] = {
> +		{ .name = "yuv-rgb-bt601",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv601_rgb601, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT601,
> +		  .range = IGT_COLOR_YCBCR_FULL_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt709",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv709_rgb709, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT709,
> +		  .range = IGT_COLOR_YCBCR_FULL_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt2020",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv2020_rgb2020, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT2020,
> +		  .range = IGT_COLOR_YCBCR_FULL_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt601-lim",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv601_rgb601_lim, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT601,
> +		  .range = IGT_COLOR_YCBCR_LIMITED_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt709-lim",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv709_rgb709_lim, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT709,
> +		  .range = IGT_COLOR_YCBCR_LIMITED_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt2020-lim",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv2020_rgb2020_lim, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT2020,
> +		  .range = IGT_COLOR_YCBCR_LIMITED_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt601-lut1d",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv601_rgb601, &lut1d_linear, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT601,
> +		  .range = IGT_COLOR_YCBCR_FULL_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt709-lut1d",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv709_rgb709, &lut1d_linear, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT709,
> +		  .range = IGT_COLOR_YCBCR_FULL_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt2020-lut1d",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv2020_rgb2020, &lut1d_linear, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT2020,
> +		  .range = IGT_COLOR_YCBCR_FULL_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt601-lim-lut1d",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv601_rgb601_lim, &lut1d_linear, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT601,
> +		  .range = IGT_COLOR_YCBCR_LIMITED_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt709-lim-lut1d",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv709_rgb709_lim, &lut1d_linear, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT709,
> +		  .range = IGT_COLOR_YCBCR_LIMITED_RANGE,
> +		},
> +		{ .name = "yuv-rgb-bt2020-lim-lut1d",
> +		  .subtest_prefix = "plane-fixed-matrix",
> +		  .fb_colors = colors_rgb,
> +		  .colorops = { &fixed_matrix_yuv2020_rgb2020_lim, &lut1d_linear, NULL },
> +		  .input_format = DRM_FORMAT_YUYV,
> +		  .encoding = IGT_COLOR_YCBCR_BT2020,
> +		  .range = IGT_COLOR_YCBCR_LIMITED_RANGE,
> +		},
> +	};
> +
> +	for (int i = 0; i < ARRAY_SIZE(fixed_matrix_tests); i++) {
> +		igt_describe_f("Test FIXED_MATRIX pipeline: %s-%s",
> +			       fixed_matrix_tests[i].subtest_prefix,
> +			       fixed_matrix_tests[i].name);
> +		igt_subtest_with_dynamic_f("%s-%s",
> +					   fixed_matrix_tests[i].subtest_prefix,
> +					   fixed_matrix_tests[i].name) {
> +			for_each_crtc_with_single_output(&data->display, crtc,
> +							 output) {
> +				data->output = output;
> +
> +				if (!crtc_output_combo_valid(data, crtc))
> +					continue;
> +
> +				port_idx = test_setup(data, crtc);
> +				if (port_idx < 0) {
> +					test_cleanup(data);
> +					continue;
> +				}
> +
> +				test_plane_fixed_matrix_colorops(data, crtc,
> +								 fixed_matrix_tests[i].fb_colors,
> +								 fixed_matrix_tests[i].colorops,
> +								 fixed_matrix_tests[i].input_format,
> +								 fixed_matrix_tests[i].encoding,
> +								 fixed_matrix_tests[i].range,
> +								 port_idx);
> +
> +				test_cleanup(data);
> +			}
> +		}
> +	}
> +}
> +
>   int igt_main()
>   {
>   	int i;
> @@ -404,6 +708,9 @@ int igt_main()
>   	igt_subtest_group()
>   		run_tests_for_plane(&data);
>   
> +	igt_subtest_group()
> +		run_tests_for_fixed_matrix(&data);
> +
>   	igt_fixture() {
>   		igt_display_fini(&data.display);
>   		drm_close_driver(data.drm_fd);