Re: [v2] tests/kms_vrr: add support for full range refresh rate testing

[Jani Nikula <jani.nikula@intel.com>]

On Tue, 28 Apr 2026, Lee Shawn C <shawn.c.lee@intel.com> wrote:
> Currently, kms_vrr tests fixed step increments within the VRR range.
> To better validate hardware stability and potential issues across the
> entire spectrum, this patch adds a 'full-range' testing mode.
>
> When the full-range flag is enabled, the test will:
> 1. Iterate from the maximum to the minimum refresh rate (stepping by 1).
> 2. For standard testing, maintain the existing behavior of incrementing
>    from minimum to maximum using the defined step size.
>
> v2: Fix build failure by adding documentation for the new subtest.
>
> Signed-off-by: Lee Shawn C <shawn.c.lee@intel.com>
> ---
>  tests/kms_vrr.c | 32 ++++++++++++++++++++++++++------
>  1 file changed, 26 insertions(+), 6 deletions(-)
>
> diff --git a/tests/kms_vrr.c b/tests/kms_vrr.c
> index 6043d40f1d74..b8a8c6aa79ed 100644
> --- a/tests/kms_vrr.c
> +++ b/tests/kms_vrr.c
> @@ -66,6 +66,9 @@
>   * Description: Test to create a Virtual Mode in VRR range and switch to it
>   * 		without a full modeset.
>   *
> + * SUBTEST: seamless-rr-switch-virtual-full
> + * Description: Vrr seamless refresh rate switch for virtual modes using full range
> + *
>   * SUBTEST: lobf
>   * Description: Test to validate link-off between active frames in non-psr
>   *              operation
> @@ -93,9 +96,10 @@ enum {
>  	TEST_FLIPLINE = 1 << 3,
>  	TEST_SEAMLESS_VRR = 1 << 4,
>  	TEST_SEAMLESS_DRRS = 1 << 5,
> -	TEST_SEAMLESS_VIRTUAL_RR = 1 << 6,
> -	TEST_FASTSET = 1 << 7,
> -	TEST_MAXMIN = 1 << 8,
> +	TEST_SEAMLESS_VIRTUAL_RR_FAST = 1 << 6,
> +	TEST_SEAMLESS_VIRTUAL_RR_FULL = 1 << 7,
> +	TEST_FASTSET = 1 << 8,
> +	TEST_MAXMIN = 1 << 9,
>  	TEST_LINK_OFF = 1 << 10,
>  	TEST_NEGATIVE = 1 << 11,
>  	TEST_FORCE_RR = 1 << 12,
> @@ -754,10 +758,12 @@ test_seamless_virtual_rr_basic(data_t *data, igt_crtc_t *crtc,
>  			       igt_output_t *output, uint32_t flags)
>  {
>  	uint32_t result;
> -	unsigned int vrefresh;
> +	int vrefresh;
>  	uint64_t rate[] = {0};
>  	uint32_t step_size;
> +	int start, end, step;
>  	drmModeModeInfo virtual_mode;
> +	bool full_vrr_range = !!(flags & TEST_SEAMLESS_VIRTUAL_RR_FULL);

Nitpick, that !! is a thing of the past, and completely unnecessary with
stdbool.

BR,
Jani.

>  
>  	igt_info("Use HIGH_RR Mode as default\n");
>  	kmstest_dump_mode(&data->switch_modes[HIGH_RR_MODE]);
> @@ -795,7 +801,17 @@ test_seamless_virtual_rr_basic(data_t *data, igt_crtc_t *crtc,
>  		   (((data->range.max + data->range.min) / 2) + step_size) :
>  		   data->range.min + step_size;
>  
> -	for ( ; vrefresh < data->range.max; vrefresh += step_size) {
> +	if (full_vrr_range) {
> +		start = data->range.max;
> +		end = data->range.min;
> +		step = -1;
> +	} else {
> +		start = data->range.min;
> +		end = data->range.max;
> +		step = step_size;
> +	}
> +
> +	for (vrefresh = start; (step > 0) ? (vrefresh <= end) : (vrefresh >= end); vrefresh += step) {
>  		virtual_rr_vrr_range_mode(&virtual_mode, vrefresh);
>  
>  		igt_info("Requesting Virtual Mode with Refresh Rate (%u Hz): \n", vrefresh);
> @@ -1103,7 +1119,11 @@ int igt_main_args("drs:", long_opts, help_str, opt_handler, &data)
>  
>  		igt_describe("Test to switch to any custom virtual mode in VRR range without modeset.");
>  		igt_subtest_with_dynamic("seamless-rr-switch-virtual")
> -			run_vrr_test(&data, test_seamless_virtual_rr_basic, TEST_SEAMLESS_VIRTUAL_RR);
> +			run_vrr_test(&data, test_seamless_virtual_rr_basic, TEST_SEAMLESS_VIRTUAL_RR_FAST);
> +
> +		igt_describe("Test to switch to all virtual modes in VRR range without modeset.");
> +		igt_subtest_with_dynamic("seamless-rr-switch-virtual-full")
> +			run_vrr_test(&data, test_seamless_virtual_rr_basic, TEST_SEAMLESS_VIRTUAL_RR_FULL);
>  
>  		igt_describe("Test to validate the link-off between active frames in "
>  			     "non-PSR operation.");

-- 
Jani Nikula, Intel