| Message ID | 20231013140214.1713-1-ville.syrjala@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915/bios: Clamp VBT HDMI level shift on BDW | expand |
On 10/13/2023 7:32 PM, Ville Syrjala wrote: > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > Apparently some BDW machines (eg. HP Pavilion 15-ab) shipped with > a VBT inherited from some earlier HSW model. On HSW the HDMI level > shift value could go up to 11, whereas on BDW the maximum value is > 9. > > The DDI code does clamp the bogus value, but it does so with > a WARN which we don't really want. To avoid that let's just sanitize > the bogus VBT HDMI level shift value ahead of time for all BDW machines. > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9461 > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > --- > drivers/gpu/drm/i915/display/intel_bios.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c > index 4e8f1e91bb08..8f83f0ead27f 100644 > --- a/drivers/gpu/drm/i915/display/intel_bios.c > +++ b/drivers/gpu/drm/i915/display/intel_bios.c > @@ -2473,6 +2473,27 @@ static void sanitize_device_type(struct intel_bios_encoder_data *devdata, > devdata->child.device_type |= DEVICE_TYPE_NOT_HDMI_OUTPUT; > } > > +static void sanitize_hdmi_level_shift(struct intel_bios_encoder_data *devdata, > + enum port port) > +{ > + struct drm_i915_private *i915 = devdata->i915; > + > + if (!intel_bios_encoder_supports_dvi(devdata)) > + return; > + > + /* > + * Some BDW machines (eg. HP Pavilion 15-ab) shipped > + * with a HSW VBT where the level shifter value goes > + * up to 11, whereas the BDW max is 9. I hope this is just one off case, where incorrect VBT is used. Verified from Bspec:4299 and _bdw_trans_hdmi entries. Change looks good to me. Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> > + */ > + if (IS_BROADWELL(i915) && devdata->child.hdmi_level_shifter_value > 9) { > + drm_dbg_kms(&i915->drm, "Bogus port %c VBT HDMI level shift %d, adjusting to %d\n", > + port_name(port), devdata->child.hdmi_level_shifter_value, 9); > + > + devdata->child.hdmi_level_shifter_value = 9; > + } > +} > + > static bool > intel_bios_encoder_supports_crt(const struct intel_bios_encoder_data *devdata) > { > @@ -2652,6 +2673,7 @@ static void parse_ddi_port(struct intel_bios_encoder_data *devdata) > } > > sanitize_device_type(devdata, port); > + sanitize_hdmi_level_shift(devdata, port); > } > > static bool has_ddi_port_info(struct drm_i915_private *i915)
diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index 4e8f1e91bb08..8f83f0ead27f 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -2473,6 +2473,27 @@ static void sanitize_device_type(struct intel_bios_encoder_data *devdata, devdata->child.device_type |= DEVICE_TYPE_NOT_HDMI_OUTPUT; } +static void sanitize_hdmi_level_shift(struct intel_bios_encoder_data *devdata, + enum port port) +{ + struct drm_i915_private *i915 = devdata->i915; + + if (!intel_bios_encoder_supports_dvi(devdata)) + return; + + /* + * Some BDW machines (eg. HP Pavilion 15-ab) shipped + * with a HSW VBT where the level shifter value goes + * up to 11, whereas the BDW max is 9. + */ + if (IS_BROADWELL(i915) && devdata->child.hdmi_level_shifter_value > 9) { + drm_dbg_kms(&i915->drm, "Bogus port %c VBT HDMI level shift %d, adjusting to %d\n", + port_name(port), devdata->child.hdmi_level_shifter_value, 9); + + devdata->child.hdmi_level_shifter_value = 9; + } +} + static bool intel_bios_encoder_supports_crt(const struct intel_bios_encoder_data *devdata) { @@ -2652,6 +2673,7 @@ static void parse_ddi_port(struct intel_bios_encoder_data *devdata) } sanitize_device_type(devdata, port); + sanitize_hdmi_level_shift(devdata, port); } static bool has_ddi_port_info(struct drm_i915_private *i915)