On Sat, 27 Aug 2022, Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> wrote: > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > A bunch of machines seem to have eDP panels where the EDID > indicates continuous frequency support but fails to actually > include the range descirptor. This violates the EDID 1.4 > spec, but looks like the Windows driver just hacks around > this by just assuming that the panel supports a continuous > refresh rate range that covers all EDID reported modes. > > Do the same so that we get VRR support on these machines. > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6323 > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/i915/display/intel_dp.c | 45 +++++++++++++++++++++++++ > 1 file changed, 45 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c > index 8d1559323412..1f3e4824d316 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp.c > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > @@ -5207,6 +5207,49 @@ intel_edp_add_properties(struct intel_dp *intel_dp) > fixed_mode->vdisplay); > } > > +/* > + * Some VRR eDP panels violate the EDID spec and neglect > + * to include the monitor range descriptor in the EDID. > + * Cook up the VRR refresh rate limits based on the modes > + * reported by the panel. > + */ > +static void > +intel_edp_infer_vrr_range(struct intel_connector *connector) > +{ > + struct drm_i915_private *i915 = to_i915(connector->base.dev); > + struct drm_display_info *info = &connector->base.display_info; > + const struct edid *edid = connector->edid; > + const struct drm_display_mode *mode; > + > + if (!HAS_VRR(i915)) > + return; > + > + if (!edid || edid->revision < 4 || connector->edid is actually an error pointer. I made it so way back when to differentiate between "broken edid" -EINVAL and "no edid" -ENOENT, but I don't think we ever use that distinction anywhere. Either ditch the error pointers (in a separate patch) or check for them here. With that fixed, Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx> > + !(edid->features & DRM_EDID_FEATURE_CONTINUOUS_FREQ) || > + info->vrr_range.min_vfreq || info->vrr_range.max_vfreq) > + return; > + > + if (list_empty(&connector->base.probed_modes)) > + return; > + > + info->vrr_range.min_vfreq = ~0; > + info->vrr_range.max_vfreq = 0; > + > + list_for_each_entry(mode, &connector->base.probed_modes, head) { > + int vrefresh = drm_mode_vrefresh(mode); > + > + info->vrr_range.min_vfreq = min_t(int, vrefresh, > + info->vrr_range.min_vfreq); > + info->vrr_range.max_vfreq = max_t(int, vrefresh, > + info->vrr_range.max_vfreq); > + } > + > + drm_dbg_kms(&i915->drm, > + "[CONNECTOR:%d:%s] does not report refresh rate range, assuming: %d Hz - %d Hz\n", > + connector->base.base.id, connector->base.name, > + info->vrr_range.min_vfreq, info->vrr_range.max_vfreq); > +} > + > static bool intel_edp_init_connector(struct intel_dp *intel_dp, > struct intel_connector *intel_connector) > { > @@ -5271,6 +5314,8 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp, > } > intel_connector->edid = edid; > > + intel_edp_infer_vrr_range(intel_connector); > + > intel_bios_init_panel(dev_priv, &intel_connector->panel, > encoder->devdata, IS_ERR(edid) ? NULL : edid); -- Jani Nikula, Intel Open Source Graphics Center
