[igt-dev] [PATCH i-g-t] tests/kms_plane: survive cdclk caused modeset

[Ville Syrjälä]

On Tue, Apr 07, 2020 at 06:54:09PM +0300, Juha-Pekka Heikkila wrote:
> On 7.4.2020 18.36, Ville Syrjälä wrote:
> > On Tue, Apr 07, 2020 at 02:09:04PM +0300, Juha-Pekka Heikkila wrote:
> >> This change will slow this test down a bit. In mid test starting
> >> to use higher bpp pixel format (say 64bpp) can cause modeset.
> >> Use blocking commit so there's wait for modeset to happen.
> > 
> > We already wait for the event the next time around. So this
> > doesn't make sense to me.
> 
> There's those logs like this
> https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_470/fi-icl-guc/igt@kms_plane@pixel-format-pipe-c-planes-source-clamping.html
> 
> where going to 64bpp pixel format will cause modeset and fail running 
> test.

Hmm. Seems we don't have drm.debug=0x10 enabled so we don't see the
actual debug message :( Anyways, the real bug seems to be the lack of
ALLOW_MODESET.

> I was testing this on ICL and see errors randomly, on ci those 
> seem to be less random. Making this one commit blocking will cause 
> modeset to settle without interrupting test, at least on my ICL.
> 
> If there's a way to sort those pixel formats according to bpp and start 
> with highest there's no need for this.
> 
> > 
> >>
> >> Fixes: https://gitlab.freedesktop.org/drm/intel/issues/1214
> >> Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila at gmail.com>
> >> ---
> >>   tests/kms_plane.c | 6 ++----
> >>   1 file changed, 2 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/tests/kms_plane.c b/tests/kms_plane.c
> >> index 805795cd..2324fb6e 100644
> >> --- a/tests/kms_plane.c
> >> +++ b/tests/kms_plane.c
> >> @@ -569,12 +569,10 @@ static void capture_format_crcs(data_t *data, enum pipe pipe,
> >>   
> >>   		if (data->display.is_atomic) {
> >>   			/*
> >> -			 * Use non-blocking commits to allow the next fb
> >> -			 * to be prepared in parallel while the current fb
> >> -			 * awaits to be latched.
> >> +			 * Use blocking commit because there maybe
> >> +			 * modeset when going to higher bpp pixel format.
> >>   			 */
> >>   			igt_display_commit_atomic(&data->display,
> >> -						  DRM_MODE_ATOMIC_NONBLOCK |
> >>   						  DRM_MODE_PAGE_FLIP_EVENT, NULL);
> >>   		} else {
> >>   			/*
> >> -- 
> >> 2.17.1
> >>
> >> _______________________________________________
> >> igt-dev mailing list
> >> igt-dev at lists.freedesktop.org
> >> https://lists.freedesktop.org/mailman/listinfo/igt-dev
> > 

-- 
Ville Syrjälä
Intel