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. 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 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
