[PATCH v3] tests/kms_vrr: Add a subtest for seamless modeset to a virtual LRR mode

[Modem, Bhanuprakash]

Hi Manasi,

Thanks for the patch.

I don't have much exposure on this virtual LRR modes. From this patch, 
atleast I understood that you are trying to switch different refresh 
rates (without modeset) within the VRR range. And we are pretty much 
doing the same with the subtest 'igt at kms_vrr@flip-basic-fastset' with 3 
different rates.

Is there anything else we are going to achieve with this patch? Please 
throw some knowledge on this.

- Bhanu

On 19-03-2024 10:03 pm, Manasi Navare wrote:
> This subtest validates LRR fastset functionality by testing seamless switching
> without full modeset to any of the virtual LRR mode within VRR range.
> Here we start from highest refresh rate mode and then switch to virtual LRR
> modes in the steps of 10Hz within the VRR range.
> 
> This is used to test the LRR fastset functionality of the driver.
> 
> v3:
> - Fix build error due to rebase (Manasi)
> 
> Cc: Drew Davenport <ddavenport at chromium.org>
> Cc: Bhanuprakash Modem <bhanuprakash.modem at intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Sean Paul <seanpaul at chromium.org>
> Signed-off-by: Manasi Navare <navaremanasi at chromium.org>
> ---
>   tests/kms_vrr.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++-
>   1 file changed, 67 insertions(+), 1 deletion(-)
> 
> diff --git a/tests/kms_vrr.c b/tests/kms_vrr.c
> index 15c62b34b..316b626c3 100644
> --- a/tests/kms_vrr.c
> +++ b/tests/kms_vrr.c
> @@ -70,6 +70,11 @@
>    * Description: Oscillates between highest and lowest refresh each frame for
>    *              manual flicker profiling
>    *
> + * SUBTEST: seamless-virtual-rr-switch
> + * Description: Test to create a Virtual Mode in VRR range and switch to it
> + * 		without a full modeset.
> + * Functionality: LRR
> + *
>    * SUBTEST: negative-basic
>    * Description: Make sure that VRR should not be enabled on the Non-VRR panel.
>    */
> @@ -92,11 +97,13 @@ enum {
>   	TEST_FASTSET = 1 << 6,
>   	TEST_MAXMIN = 1 << 7,
>   	TEST_NEGATIVE = 1 << 8,
> +	TEST_SEAMLESS_VIRTUAL_RR = 1 << 9,
>   };
>   
>   enum {
>   	HIGH_RR_MODE,
>   	LOW_RR_MODE,
> +	VIRTUAL_RR_MODE,
>   	RR_MODES_COUNT,
>   };
>   
> @@ -214,6 +221,19 @@ low_rr_mode_with_same_res(igt_output_t *output, unsigned int vrr_min)
>   	return mode;
>   }
>   
> +static drmModeModeInfo
> +virtual_rr_vrr_range_mode(igt_output_t *output, unsigned int virtual_refresh_rate)
> +{
> +	int i;
> +	drmModeConnectorPtr connector = output->config.connector;
> +	drmModeModeInfo mode = *igt_output_get_mode(output);
> +	uint64_t clock_hz = mode.clock * 1000;
> +
> +	mode.vtotal = clock_hz / (mode.htotal * virtual_refresh_rate);
> +	mode.vrefresh = virtual_refresh_rate;
> +	return mode;
> +}
> +
>   /* Read min and max vrr range from the connector debugfs. */
>   static range_t
>   get_vrr_range(data_t *data, igt_output_t *output)
> @@ -641,6 +661,48 @@ test_seamless_rr_basic(data_t *data, enum pipe pipe, igt_output_t *output, uint3
>   		     vrr ? "on" : "off", vrr ? "not reached" : "exceeded", result);
>   }
>   
> +static void
> +test_seamless_virtual_rr_basic(data_t *data, enum pipe pipe, igt_output_t *output, uint32_t flags)
> +{
> +	uint32_t result;
> +	uint64_t rate;
> +	unsigned int vrefresh;
> +
> +	igt_info("Use HIGH_RR Mode as default\n");
> +	kmstest_dump_mode(&data->switch_modes[HIGH_RR_MODE]);
> +
> +	prepare_test(data, output, pipe);
> +	rate = rate_from_refresh(data->switch_modes[HIGH_RR_MODE].vrefresh);
> +
> +	/*
> +	 * Sink with DRR and VRR can be in downclock mode so
> +	 * switch to highest refresh rate mode.
> +	 */
> +	igt_output_override_mode(output, &data->switch_modes[HIGH_RR_MODE]);
> +	igt_assert(igt_display_try_commit_atomic(&data->display, DRM_MODE_PAGE_FLIP_EVENT, NULL) == 0);
> +
> +	result = flip_and_measure(data, output, pipe, rate, 1, TEST_DURATION_NS);
> +	igt_assert_f(result > 75,
> +		     "Refresh rate (%u Hz) %"PRIu64"ns: Target threshold not reached, result was %u%%\n",
> +		     data->switch_modes[HIGH_RR_MODE].vrefresh, rate, result);
> +
> +	/* Switch to Virtual RR */
> +	for (vrefresh = data->range.min + 10; vrefresh < data->range.max; vrefresh += 10) {
> +
> +		data->switch_modes[VIRTUAL_RR_MODE] = virtual_rr_vrr_range_mode(output, vrefresh);
> +		igt_info("Requesting Virtual Mode with Refresh Rate (%u Hz): \n", vrefresh);
> +		kmstest_dump_mode(&data->switch_modes[VIRTUAL_RR_MODE]);
> +		igt_output_override_mode(output, &data->switch_modes[VIRTUAL_RR_MODE]);
> +		igt_assert(igt_display_try_commit_atomic(&data->display, 0, NULL) == 0);
> +
> +		rate = rate_from_refresh(vrefresh);
> +		result = flip_and_measure(data, output, pipe, rate, 1, TEST_DURATION_NS);
> +		igt_assert_f(result > 75,
> +			     "Refresh rate (%u Hz) %"PRIu64"ns: Target threshold not reached, result was %u%%\n",
> +			     vrefresh, rate, result);
> +	}
> +}
> +
>   static void test_cleanup(data_t *data, enum pipe pipe, igt_output_t *output)
>   {
>   	if (vrr_capable(output))
> @@ -686,7 +748,7 @@ static bool output_constraint(data_t *data, igt_output_t *output, uint32_t flags
>   	igt_output_override_mode(output, &data->switch_modes[HIGH_RR_MODE]);
>   
>   	/* Search for a low refresh rate mode. */
> -	if (!(flags & (TEST_SEAMLESS_VRR | TEST_SEAMLESS_DRRS)))
> +	if (!(flags & (TEST_SEAMLESS_VRR | TEST_SEAMLESS_DRRS | TEST_SEAMLESS_VIRTUAL_RR)))
>   		return true;
>   
>   	data->switch_modes[LOW_RR_MODE] = low_rr_mode_with_same_res(output, data->range.min);
> @@ -841,6 +903,10 @@ igt_main_args("drs:", long_opts, help_str, opt_handler, &data)
>   			     "between flip timestamps converges to the requested rate");
>   		igt_subtest_with_dynamic("flip-basic-fastset")
>   			run_vrr_test(&data, test_basic, TEST_FASTSET);
> +
> +		igt_describe("Test to switch to any custom virtual mode in VRR range without modeset.");
> +		igt_subtest_with_dynamic("seamless-virtual-rr-switch")
> +			run_vrr_test(&data, test_seamless_virtual_rr_basic, TEST_SEAMLESS_VIRTUAL_RR);
>   	}
>   
>   	igt_fixture {