Re: [PATCH i-g-t 3/3] tests/: Handle max bpc read failures explicitly

[Karthik B S <karthik.b.s@intel.com>]

Hi Pranay,

+cc Vitaly Prosyak <vitaly.prosyak@amd.com>

@Vitaly: Please take a look from the amd tests POV.

The patch LGTM in general, other than the fact that this patch needs to 
be combined with patch 2 to avoid compilation failure there.

Regards,
Karthik.B.S

On 5/18/2026 9:33 AM, Pranay Samala wrote:
> Update test call sites of igt_get_output_max_bpc() to use the boolean
> return API so each test can decide how to handle max-bpc read failures.
> This separates read/parsing failures from capability checks and allows
> the test to make an explicit skip/continue decision with clearer logging,
> while keeping normal capability validation unchanged when max bpc is
> read successfully.
>
> Signed-off-by: Pranay Samala <pranay.samala@intel.com>
> ---
>   tests/amdgpu/amd_bypass.c              |  6 +++++-
>   tests/amdgpu/amd_dp_dsc.c              | 10 +++++++++-
>   tests/intel/kms_dsc.c                  | 13 +++++++++++--
>   tests/intel/kms_frontbuffer_tracking.c | 10 +++++++++-
>   tests/kms_color_helper.c               |  5 ++++-
>   tests/kms_dither.c                     |  9 ++++++++-
>   tests/kms_hdr.c                        | 16 ++++++++++++++--
>   7 files changed, 60 insertions(+), 9 deletions(-)
>
> diff --git a/tests/amdgpu/amd_bypass.c b/tests/amdgpu/amd_bypass.c
> index 3c537ea9e..e59691f16 100644
> --- a/tests/amdgpu/amd_bypass.c
> +++ b/tests/amdgpu/amd_bypass.c
> @@ -323,6 +323,7 @@ static void bypass_8bpc_test(data_t *data)
>   	igt_display_t *display = &data->display;
>   	igt_fb_t fb;
>   	enum pattern ptn;
> +	unsigned int maximum;
>   
>   	test_init(data);
>   
> @@ -345,7 +346,10 @@ static void bypass_8bpc_test(data_t *data)
>   	 * Rx supports only up to 6bpc, Rx-crc will different from crtc-crc
>   	 * with 8bpc.
>   	 */
> -	igt_skip_on_f(igt_get_output_max_bpc(data->output) <= 6,
> +	igt_skip_on_f(!igt_get_output_max_bpc(data->output, &maximum),
> +		      "Failed to read max bpc for %s\n", igt_output_name(data->output));
> +
> +	igt_skip_on_f(maximum <= 6,
>   		      "check /sys/kernel/debug/dri/0/eDP-1 (connector)/output_bpc\n");
>   
>   	igt_create_fb(data->drm_fd, data->width, data->height,
> diff --git a/tests/amdgpu/amd_dp_dsc.c b/tests/amdgpu/amd_dp_dsc.c
> index 1742c7df4..dc71e903e 100644
> --- a/tests/amdgpu/amd_dp_dsc.c
> +++ b/tests/amdgpu/amd_dp_dsc.c
> @@ -480,11 +480,19 @@ static void test_dsc_bpc(data_t *data)
>   
>   	/* Find max supported bpc */
>   	for_each_crtc(&data->display, crtc) {
> +		unsigned int maximum;
> +
>   		output = data->output[crtc->crtc_index];
>   		if (!output || !igt_output_is_connected(output))
>   			continue;
>   		igt_info("Checking bpc support of conn %s\n", output->name);
> -		max_supported_bpc[crtc->crtc_index] = igt_get_output_max_bpc(output);
> +		if (!igt_get_output_max_bpc(output, &maximum)) {
> +			igt_info("Failed to read max bpc for conn %s\n", output->name);
> +			max_supported_bpc[crtc->crtc_index] = 0;
> +			continue;
> +		}
> +
> +		max_supported_bpc[crtc->crtc_index] = maximum;
>   	}
>   
>   	/* Setup all outputs */
> diff --git a/tests/intel/kms_dsc.c b/tests/intel/kms_dsc.c
> index 605ad2d5c..8008fc045 100644
> --- a/tests/intel/kms_dsc.c
> +++ b/tests/intel/kms_dsc.c
> @@ -265,6 +265,8 @@ static void test_dsc(data_t *data, uint32_t test_type, int bpc,
>   	igt_require(check_gen11_bpc_constraint(data->drm_fd, data->input_bpc));
>   
>   	for_each_crtc_with_valid_output(display, crtc, output) {
> +		unsigned int maximum;
> +
>   		data->output_format = output_format;
>   		data->plane_format = plane_format;
>   		data->input_bpc = bpc;
> @@ -275,8 +277,15 @@ static void test_dsc(data_t *data, uint32_t test_type, int bpc,
>   		    !check_gen11_dp_constraint(data->drm_fd, data->output, data->crtc))
>   			continue;
>   
> -		if (igt_get_output_max_bpc(output) < MIN_DSC_BPC) {
> -			igt_info("Output %s doesn't support min %d-bpc\n", igt_output_name(data->output), MIN_DSC_BPC);
> +		if (!igt_get_output_max_bpc(output, &maximum)) {
> +			igt_info("Output %s: Failed to read max bpc\n",
> +				 igt_output_name(data->output));
> +			continue;
> +		}
> +
> +		if (maximum < MIN_DSC_BPC) {
> +			igt_info("Output %s doesn't support min %d-bpc\n",
> +				 igt_output_name(data->output), MIN_DSC_BPC);
>   			continue;
>   		}
>   
> diff --git a/tests/intel/kms_frontbuffer_tracking.c b/tests/intel/kms_frontbuffer_tracking.c
> index e7bb3fa18..996a67ee6 100644
> --- a/tests/intel/kms_frontbuffer_tracking.c
> +++ b/tests/intel/kms_frontbuffer_tracking.c
> @@ -2777,6 +2777,8 @@ static void setup_drrs(void)
>   
>   static void setup_hdr(void)
>   {
> +	unsigned int maximum;
> +
>   	if (!igt_output_has_prop(prim_mode_params.output, IGT_CONNECTOR_MAX_BPC) ||
>   	    !igt_output_get_prop(prim_mode_params.output, IGT_CONNECTOR_MAX_BPC) ||
>   	    !igt_output_supports_hdr(prim_mode_params.output)) {
> @@ -2790,7 +2792,13 @@ static void setup_hdr(void)
>   		return;
>   	}
>   
> -	if (igt_get_output_max_bpc(prim_mode_params.output) < 10) {
> +	if (!igt_get_output_max_bpc(prim_mode_params.output, &maximum)) {
> +		igt_info("Can't test HDR: Failed to read max bpc for %s.\n",
> +			 igt_output_name(prim_mode_params.output));
> +		return;
> +	}
> +
> +	if (maximum < 10) {
>   		igt_info("Can't test HDR: %s doesn't support 10 bpc.\n", igt_output_name(prim_mode_params.output));
>   		return;
>   	}
> diff --git a/tests/kms_color_helper.c b/tests/kms_color_helper.c
> index 24663444a..a50ac3a37 100644
> --- a/tests/kms_color_helper.c
> +++ b/tests/kms_color_helper.c
> @@ -40,7 +40,10 @@ bool crtc_output_combo_valid(data_t *data, igt_crtc_t *crtc)
>   bool
>   panel_supports_deep_color(igt_output_t *output)
>   {
> -	unsigned int maximum = igt_get_output_max_bpc(output);
> +	unsigned int maximum;
> +
> +	if (!igt_get_output_max_bpc(output, &maximum))
> +		return false;
>   
>   	igt_info("Max supported bit depth: %d\n", maximum);
>   
> diff --git a/tests/kms_dither.c b/tests/kms_dither.c
> index ca367db61..236e5c7c0 100644
> --- a/tests/kms_dither.c
> +++ b/tests/kms_dither.c
> @@ -206,6 +206,7 @@ run_dither_test(data_t *data, int fb_bpc, int fb_format, int output_bpc)
>   
>   	for_each_connected_output(display, output) {
>   		igt_crtc_t *crtc;
> +		unsigned int maximum;
>   
>   		if (!is_supported(output)) {
>   			igt_info("Output %s: Doesn't support \"max bpc\" property.\n",
> @@ -213,7 +214,13 @@ run_dither_test(data_t *data, int fb_bpc, int fb_format, int output_bpc)
>   			continue;
>   		}
>   
> -		if (igt_get_output_max_bpc(output) < output_bpc) {
> +		if (!igt_get_output_max_bpc(output, &maximum)) {
> +			igt_info("Output %s: Failed to read max bpc.\n",
> +				 igt_output_name(output));
> +			continue;
> +		}
> +
> +		if (maximum < output_bpc) {
>   			igt_info("Output %s: Doesn't support %d-bpc.\n",
>   				 igt_output_name(output), output_bpc);
>   			continue;
> diff --git a/tests/kms_hdr.c b/tests/kms_hdr.c
> index bcc912d15..2f19b3237 100644
> --- a/tests/kms_hdr.c
> +++ b/tests/kms_hdr.c
> @@ -254,6 +254,7 @@ static void test_bpc_switch(data_t *data, uint32_t flags)
>   
>   	for_each_connected_output(display, output) {
>   		igt_crtc_t *crtc;
> +		unsigned int maximum;
>   
>   		if (!has_max_bpc(output)) {
>   			igt_info("%s: Doesn't support IGT_CONNECTOR_MAX_BPC.\n",
> @@ -261,7 +262,12 @@ static void test_bpc_switch(data_t *data, uint32_t flags)
>   			continue;
>   		}
>   
> -		if (igt_get_output_max_bpc(output) < 10) {
> +		if (!igt_get_output_max_bpc(output, &maximum)) {
> +			igt_info("%s: Failed to read max bpc.\n", igt_output_name(output));
> +			continue;
> +		}
> +
> +		if (maximum < 10) {
>   			igt_info("%s: Doesn't support 10 bpc.\n", igt_output_name(output));
>   			continue;
>   		}
> @@ -532,6 +538,7 @@ static void test_hdr(data_t *data, uint32_t flags)
>   
>   	for_each_connected_output(display, output) {
>   		igt_crtc_t *crtc;
> +		unsigned int maximum;
>   
>   		/* To test HDR, 10 bpc is required, so we need to
>   		 * set MAX_BPC property to 10bpc prior to setting
> @@ -556,7 +563,12 @@ static void test_hdr(data_t *data, uint32_t flags)
>   			continue;
>   		}
>   
> -		if (igt_get_output_max_bpc(output) < 10) {
> +		if (!igt_get_output_max_bpc(output, &maximum)) {
> +			igt_info("%s: Failed to read max bpc.\n", igt_output_name(output));
> +			continue;
> +		}
> +
> +		if (maximum < 10) {
>   			igt_info("%s: Doesn't support 10 bpc.\n", igt_output_name(output));
>   			continue;
>   		}