On Fri, Jul 15, 2022 at 11:20:44PM +0300, Ville Syrjala wrote: > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > Limit the DP lane count based on the new VBT DP/eDP max > lane count field. > > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/i915/display/intel_bios.c | 16 ++++++++++++++++ > drivers/gpu/drm/i915/display/intel_bios.h | 1 + > drivers/gpu/drm/i915/display/intel_dp.c | 13 ++++++++++++- > 3 files changed, 29 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c > index cd86b65055ef..d8063c329b3a 100644 > --- a/drivers/gpu/drm/i915/display/intel_bios.c > +++ b/drivers/gpu/drm/i915/display/intel_bios.c > @@ -2489,6 +2489,14 @@ static int _intel_bios_dp_max_link_rate(const struct intel_bios_encoder_data *de > return parse_bdb_216_dp_max_link_rate(devdata->child.dp_max_link_rate); > } > > +static int _intel_bios_dp_max_lane_count(const struct intel_bios_encoder_data *devdata) > +{ > + if (!devdata || devdata->i915->vbt.version < 244) > + return 0; > + > + return devdata->child.dp_max_lane_count + 1; > +} > + > static void sanitize_device_type(struct intel_bios_encoder_data *devdata, > enum port port) > { > @@ -3674,6 +3682,14 @@ int intel_bios_dp_max_link_rate(struct intel_encoder *encoder) > return _intel_bios_dp_max_link_rate(devdata); > } > > +int intel_bios_dp_max_lane_count(struct intel_encoder *encoder) > +{ > + struct drm_i915_private *i915 = to_i915(encoder->base.dev); > + const struct intel_bios_encoder_data *devdata = i915->vbt.ports[encoder->port]; > + > + return _intel_bios_dp_max_lane_count(devdata); > +} do we really need 2 functions here since this one is small and we don't have any bit switches and all?! or do you plan to reuse this anywhere else later? > + > int intel_bios_alternate_ddc_pin(struct intel_encoder *encoder) > { > struct drm_i915_private *i915 = to_i915(encoder->base.dev); > diff --git a/drivers/gpu/drm/i915/display/intel_bios.h b/drivers/gpu/drm/i915/display/intel_bios.h > index e47582b0de0a..e375405a7828 100644 > --- a/drivers/gpu/drm/i915/display/intel_bios.h > +++ b/drivers/gpu/drm/i915/display/intel_bios.h > @@ -258,6 +258,7 @@ bool intel_bios_get_dsc_params(struct intel_encoder *encoder, > int intel_bios_max_tmds_clock(struct intel_encoder *encoder); > int intel_bios_hdmi_level_shift(struct intel_encoder *encoder); > int intel_bios_dp_max_link_rate(struct intel_encoder *encoder); > +int intel_bios_dp_max_lane_count(struct intel_encoder *encoder); > int intel_bios_alternate_ddc_pin(struct intel_encoder *encoder); > bool intel_bios_port_supports_typec_usb(struct drm_i915_private *i915, enum port port); > bool intel_bios_port_supports_tbt(struct drm_i915_private *i915, enum port port); > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c > index 32292c0be2bd..0370c4c105dc 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp.c > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > @@ -286,11 +286,22 @@ static int intel_dp_max_common_rate(struct intel_dp *intel_dp) > return intel_dp_common_rate(intel_dp, intel_dp->num_common_rates - 1); > } > > +static int intel_dp_max_source_lane_count(struct intel_digital_port *dig_port) > +{ > + int vbt_max_lanes = intel_bios_dp_max_lane_count(&dig_port->base); > + int max_lanes = dig_port->max_lanes; > + > + if (vbt_max_lanes) > + max_lanes = min(max_lanes, vbt_max_lanes); > + > + return max_lanes; > +} > + > /* Theoretical max between source and sink */ > static int intel_dp_max_common_lane_count(struct intel_dp *intel_dp) > { > struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp); > - int source_max = dig_port->max_lanes; > + int source_max = intel_dp_max_source_lane_count(dig_port); > int sink_max = intel_dp->max_sink_lane_count; > int fia_max = intel_tc_port_fia_max_lane_count(dig_port); > int lttpr_max = drm_dp_lttpr_max_lane_count(intel_dp->lttpr_common_caps); > -- > 2.35.1 >