On Thu, Feb 13, 2020 at 11:03:29PM +0200, Jani Nikula wrote: > On Thu, 13 Feb 2020, Matt Roper <matthew.d.roper@xxxxxxxxx> wrote: > > On Thu, Feb 13, 2020 at 04:04:11PM +0200, Stanislav Lisovskiy wrote: > >> From: Jani Nikula <jani.nikula@xxxxxxxxx> > >> > >> We lack full state readout of DSC config, which may lead to DSC enable > >> using a config that's all zeros, failing spectacularly. Force full > >> modeset and thus compute config at probe to get a sane state, until we > >> implement DSC state readout. Any fastset that did appear to work with > >> DSC at probe, worked by coincidence. [1] is an example of a change that > >> triggered the issue on TGL DSI DSC. > >> > >> [1] http://patchwork.freedesktop.org/patch/msgid/20200212150102.7600-1-ville.syrjala@xxxxxxxxxxxxxxx > >> > >> Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx> > >> Cc: Vandita Kulkarni <vandita.kulkarni@xxxxxxxxx> > >> Cc: Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> > >> Cc: stable@xxxxxxxxxxxxxxx > >> Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> > > > > Should this be > > > > Fixes: fbacb15ea814 ("drm/i915/dsc: add basic hardware state readout support") > > > > since that's where we added the basic readout with a FIXME to add more > > later? > > That added some readout and checks, but the problem existed before them > too. Right, but that's as far back as we can go with a fix, right? Since before that we don't even read out enough to know that compression is enabled? Matt > > BR, > Jani. > > > > > > > I don't know the specifics of DSC and what state we need, but the > > approach here seems reasonable. > > > > Acked-by: Matt Roper <matthew.d.roper@xxxxxxxxx> > > > >> --- > >> drivers/gpu/drm/i915/display/intel_display.c | 18 ++++++++++++++++++ > >> 1 file changed, 18 insertions(+) > >> > >> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > >> index 61ba1f2256a0..1e3f2cc27db8 100644 > >> --- a/drivers/gpu/drm/i915/display/intel_display.c > >> +++ b/drivers/gpu/drm/i915/display/intel_display.c > >> @@ -17828,6 +17828,24 @@ static int intel_initial_commit(struct drm_device *dev) > >> * have readout for pipe gamma enable. > >> */ > >> crtc_state->uapi.color_mgmt_changed = true; > >> + > >> + /* > >> + * FIXME hack to force full modeset when DSC is being > >> + * used. > >> + * > >> + * As long as we do not have full state readout and > >> + * config comparison of crtc_state->dsc, we have no way > >> + * to ensure reliable fastset. Remove once we have > >> + * readout for DSC. > >> + */ > >> + if (crtc_state->dsc.compression_enable) { > >> + ret = drm_atomic_add_affected_connectors(state, > >> + &crtc->base); > >> + if (ret) > >> + goto out; > >> + crtc_state->uapi.mode_changed = true; > >> + drm_dbg_kms(dev, "Force full modeset for DSC\n"); > >> + } > >> } > >> } > >> > >> -- > >> 2.24.1.485.gad05a3d8e5 > >> > >> _______________________________________________ > >> Intel-gfx mailing list > >> Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx > > -- > Jani Nikula, Intel Open Source Graphics Center -- Matt Roper Graphics Software Engineer VTT-OSGC Platform Enablement Intel Corporation (916) 356-2795 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
