Re: [PATCH i-g-t v8 7/7] tests/intel/kms_pm_dc: Add dc3co-vpb-framegap subtest

["Thasleem, Mohammed" <mohammed.thasleem@intel.com>]

LGTM:
Reviewed-by: Mohammed Thasleem <mohammed.thasleem@intel.com>

On 27-05-2026 02:19 pm, Jeevan B wrote:
> Add a new subtest to validate DC3CO counter increments across
> frame gaps exceeding the threshold during a video-like workload
> with PSR2/PR enabled.
>
> v2: Update commit message and test description.
>
> Signed-off-by: Jeevan B <jeevan.b@intel.com>
> ---
>   tests/intel/kms_pm_dc.c | 91 +++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 91 insertions(+)
>
> diff --git a/tests/intel/kms_pm_dc.c b/tests/intel/kms_pm_dc.c
> index 59cb9983d..3f17effc8 100644
> --- a/tests/intel/kms_pm_dc.c
> +++ b/tests/intel/kms_pm_dc.c
> @@ -60,6 +60,10 @@
>    *              exit cycle, ensuring DC3CO is not broken by deeper power state
>    *              transitions.
>    *
> + * SUBTEST: dc3co-vpb-framegap
> + * Description: Validate DC3CO counter increments before and after a delay greater
> + *              than 6 frame gaps during video-like load with PSR2 active.
> + *
>    * SUBTEST: dc5-dpms
>    * Description: Validate display engine entry to DC5 state while all connectors's
>    *              DPMS property set to OFF
> @@ -427,6 +431,63 @@ static void test_dc3co_framedrop(data_t *data)
>   	cleanup_dc3co_fbs(data);
>   }
>   
> +static void check_dc3co_with_framegap_load(data_t *data)
> +{
> +	igt_plane_t *primary;
> +	uint32_t dc3co_cnt_before, dc3co_cnt_after_gap;
> +	int delay, long_gap_us;
> +	time_t secs = 3;
> +	time_t start_time;
> +
> +	primary = igt_output_get_plane_type(data->output, DRM_PLANE_TYPE_PRIMARY);
> +	igt_plane_set_fb(primary, NULL);
> +
> +	delay = 1.5 * ((1000 * 1000) / data->mode->vrefresh);
> +
> +	dc3co_cnt_before = igt_read_dc_counter(data->debugfs_fd,
> +			   IGT_INTEL_CHECK_DC3CO);
> +	start_time = time(NULL);
> +	while (time(NULL) - start_time < secs) {
> +		igt_plane_set_fb(primary, &data->fb_rgb);
> +		igt_display_commit(&data->display);
> +		usleep(delay);
> +
> +		igt_plane_set_fb(primary, &data->fb_rgr);
> +		igt_display_commit(&data->display);
> +		usleep(delay);
> +	}
> +
> +	assert_dc_counter(data, IGT_INTEL_CHECK_DC3CO, dc3co_cnt_before);
> +
> +	long_gap_us = 7 * ((1000 * 1000) / data->mode->vrefresh);
> +	usleep(long_gap_us);
> +
> +	dc3co_cnt_after_gap = igt_read_dc_counter(data->debugfs_fd,
> +						  IGT_INTEL_CHECK_DC3CO);
> +	start_time = time(NULL);
> +	while (time(NULL) - start_time < secs) {
> +		igt_plane_set_fb(primary, &data->fb_rgb);
> +		igt_display_commit(&data->display);
> +		usleep(delay);
> +
> +		igt_plane_set_fb(primary, &data->fb_rgr);
> +		igt_display_commit(&data->display);
> +		usleep(delay);
> +	}
> +
> +	assert_dc_counter(data, IGT_INTEL_CHECK_DC3CO, dc3co_cnt_after_gap);
> +}
> +
> +static void test_dc3co_vpb_framegap(data_t *data)
> +{
> +	igt_require_dc_counter(data->debugfs_fd, IGT_INTEL_CHECK_DC3CO);
> +	setup_output(data);
> +	setup_dc3co(data);
> +	setup_videoplayback(data);
> +	check_dc3co_with_framegap_load(data);
> +	cleanup_dc3co_fbs(data);
> +}
> +
>   static void test_dc5_retention_flops(data_t *data, int dc_flag)
>   {
>   	uint32_t dc_counter_before_psr;
> @@ -854,6 +915,36 @@ int igt_main()
>   		}
>   	}
>   
> +	igt_describe("Validate DC3CO counter increments before and after a delay "
> +		     "greater than 6 frame gaps during video-like load with PSR2/PR active");
> +	igt_subtest_with_dynamic("dc3co-vpb-framegap") {
> +		static const struct dc3co_test_mode dc3co_modes[] = {
> +			{ PSR_MODE_2, "psr2" },
> +			{ PR_MODE,    "pr"   },
> +		};
> +
> +		for (int i = 0; i < ARRAY_SIZE(dc3co_modes); i++) {
> +			const char *name = dc3co_modes[i].name;
> +			data.op_psr_mode = dc3co_modes[i].mode;
> +
> +			igt_dynamic_f("%s", name) {
> +				igt_require(psr_sink_support(data.drm_fd,
> +						     data.debugfs_fd,
> +						     data.op_psr_mode, NULL));
> +
> +				if (data.op_psr_mode == PSR_MODE_2)
> +					igt_require_f(IS_TIGERLAKE(data.devid) ||
> +						      intel_display_ver(data.devid) >= 35,
> +						      "Platform does not support DC3CO with PSR2\n");
> +				else
> +					igt_require_f(intel_display_ver(data.devid) >= 35,
> +						      "Platform does not support DC3CO with Panel Replay\n");
> +
> +				test_dc3co_vpb_framegap(&data);
> +			}
> +		}
> +	}
> +
>   	igt_describe("This test validates display engine entry to DC5 state "
>   		     "while PSR is active");
>   	igt_subtest("dc5-psr") {