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

[Golani, Mitulkumar Ajitkumar]

> -----Original Message-----
> From: Modem, Bhanuprakash <bhanuprakash.modem at intel.com>
> Sent: Tuesday, January 9, 2024 3:48 PM
> To: Modem, Bhanuprakash <bhanuprakash.modem at intel.com>; Golani,
> Mitulkumar Ajitkumar <mitulkumar.ajitkumar.golani at intel.com>; igt-
> dev at lists.freedesktop.org
> Subject: Re: [i-g-t 1/2] tests/kms_vrr: Tweak flipline subtest
> 
> + 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);

Changes LGTM
Reviewed-by: Mitul Golani <mitulkumar.ajitkumar.golani at intel.com>

> >   	}
> >
> >   	/*