[i-g-t 1/2] tests/kms_vrr: Tweak flipline subtest

[Modem, Bhanuprakash]

+ Mitul to review

On 13-12-2023 03:23 pm, Bhanuprakash Modem wrote:
> As per the spec: If there is no flip request with in Vmax,
> Hardware will terminate the Vblank at Vmax.
> 
> If we flip with the interval > Vmax, the expected refresh rate
> could be: (Vmax + time left for the next flip + Vmin), and it
> is very difficult to generalize. For low refresh rate panels
> (like 40 - 60 Hz), result is not falling into the threshold.
> 
> Hence, tweak the test to increase the flip request interval.
> 
> Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem at intel.com>
> ---
>   tests/kms_vrr.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/kms_vrr.c b/tests/kms_vrr.c
> index 1ace970a5..71fc36162 100644
> --- a/tests/kms_vrr.c
> +++ b/tests/kms_vrr.c
> @@ -481,11 +481,11 @@ test_basic(data_t *data, enum pipe pipe, igt_output_t *output, uint32_t flags)
>   	}
>   
>   	if (flags & TEST_FLIPLINE) {
> -		rate = rate_from_refresh(range.min - 5);
> +		rate = rate_from_refresh(range.min - 10);
>   		result = flip_and_measure(data, output, pipe, rate, TEST_DURATION_NS);
>   		igt_assert_f(result < 50,
>   			     "Refresh rate (%u Hz) %"PRIu64"ns: Target VRR on threshold exceeded, result was %u%%\n",
> -			     (range.min - 5), rate, result);
> +			     (range.min - 10), rate, result);
>   	}
>   
>   	/*