[igt-dev] [PATCH i-g-t] tests/kms_plane_lowres: Test only with one plane

[Kahola, Mika]

On Fri, 2020-01-17 at 14:13 +0200, Petri Latvala wrote:
> On Fri, Jan 17, 2020 at 11:17:49AM +0200, Mika Kahola wrote:
> > The test is intended to test resolution changes from higher to
> > lower and back. We can test this with only one plane and we don't
> > need to run through all planes. This will save significant amount
> > of test execution time.
> > 
> > Fix for
> > Bugzilla: https://gitlab.freedesktop.org/drm/intel/issues/899
> 
> I'm having a hard time understanding how this change fixes this
> issue.
For some reason crc's don't match if we loop through multiple overlay
planes. The reference image has primary, first overlay and cursors
plane. Crc already fails if we compare the reference with the image
having primary, second overlay and cursor plane. This I have been
testing with TGL.

> 
> 
> > 
> > Signed-off-by: Mika Kahola <mika.kahola at intel.com>
> > ---
> >  tests/kms_plane_lowres.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/tests/kms_plane_lowres.c b/tests/kms_plane_lowres.c
> > index 4c3f5636..ee6fb1fb 100644
> > --- a/tests/kms_plane_lowres.c
> > +++ b/tests/kms_plane_lowres.c
> > @@ -208,7 +208,8 @@ test_planes_on_pipe_with_output(data_t *data,
> > enum pipe pipe,
> >  		igt_assert_crc_equal(&data->ref_lowres.crc,
> > &crc_lowres);
> >  
> >  		igt_plane_set_fb(plane, NULL);
> > -		tested++;
> > +		if (tested++)
> > +			break;
> 
> At this point one must ask: Why have the count variable anymore?
> 
>