On Fri, 20 Apr 2018, Mika Kahola <mika.kahola@xxxxxxxxx> wrote: > On Thu, 2018-04-19 at 17:09 +0300, Jani Nikula wrote: >> On Wed, 18 Apr 2018, Mika Kahola <mika.kahola@xxxxxxxxx> wrote: >> > >> > When reading out CRC's we wait for a vblank on >> > intel_dp_sink_crc_start() >> > function. When we start reading out CRC's in intel_dp_sink_crc() >> > loop we >> > first wait for a vblank yielding that all in all we end up waiting >> > two >> > vblanks on the first iteration round. Therefore, let's move the >> > intel_wait_for_vblank() as the last routine that we do in an >> > iteration loop >> > in intel_dp_sink_crc(). >> > >> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103166 >> Umm, do the CI failures in the bug really use sink crc, or are they >> rather about pipe crc? >> > The bug is more on pipe crc. This just caught my attention while I was > looking into these bugs. I think the practice we've adopted is, Bugzilla: <bug that this patch should fix> References: <bug or something else that this patch is related to> > Was there a reason why we need to wait two vblanks here before running > the loop? I can't remember by heart. I'm not sure if it would make more sense to remove the vblank wait from intel_dp_sink_crc_start() instead. Even with your patch, there'll still be an extra vblank wait, you just move it to a different place. BR, Jani. > >> BR, >> Jani. >> >> >> > >> > Signed-off-by: Mika Kahola <mika.kahola@xxxxxxxxx> >> > --- >> > drivers/gpu/drm/i915/intel_dp.c | 5 +++-- >> > 1 file changed, 3 insertions(+), 2 deletions(-) >> > >> > diff --git a/drivers/gpu/drm/i915/intel_dp.c >> > b/drivers/gpu/drm/i915/intel_dp.c >> > index 62f82c4..6eb97fa 100644 >> > --- a/drivers/gpu/drm/i915/intel_dp.c >> > +++ b/drivers/gpu/drm/i915/intel_dp.c >> > @@ -3972,13 +3972,14 @@ int intel_dp_sink_crc(struct intel_dp >> > *intel_dp, struct intel_crtc_state *crtc_s >> > return ret; >> > >> > do { >> > - intel_wait_for_vblank(dev_priv, intel_crtc->pipe); >> > - >> > if (drm_dp_dpcd_readb(&intel_dp->aux, >> > DP_TEST_SINK_MISC, &buf) < >> > 0) { >> > ret = -EIO; >> > goto stop; >> > } >> > + >> > + intel_wait_for_vblank(dev_priv, intel_crtc->pipe); >> > + >> > count = buf & DP_TEST_COUNT_MASK; >> > >> > } while (--attempts && count == 0); -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
