On Wed, 27 Oct 2021, Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> wrote: > On Tue, Oct 26, 2021 at 02:01:15PM +0300, Jani Nikula wrote: >> On Mon, 25 Oct 2021, Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> wrote: >> > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> >> > >> > Looks like we never updated intel_bios_is_port_dp_dual_mode() when >> > the VBT port mapping became erratic on modern platforms. This >> > is causing us to look up the wrong child device and thus throwing >> > the heuristic off (ie. we might end looking at a child device for >> > a genuine DP++ port when we were supposed to look at one for a >> > native HDMI port). >> > >> > Fix it up by not using the outdated port_mapping[] in >> > intel_bios_is_port_dp_dual_mode() and rely on >> > intel_bios_encoder_data_lookup() instead. >> >> It's just crazy, we have like 7 port_mapping tables in intel_bios.c, >> what happened?! >> >> I wish we could unify all of this more. >> >> > >> > Cc: stable@xxxxxxxxxxxxxxx >> > Tested-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> >> > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4138 >> > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> >> > --- >> > drivers/gpu/drm/i915/display/intel_bios.c | 85 +++++++++++++++++------ >> > 1 file changed, 63 insertions(+), 22 deletions(-) >> > >> > diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c >> > index f9776ca85de3..2b1423a43437 100644 >> > --- a/drivers/gpu/drm/i915/display/intel_bios.c >> > +++ b/drivers/gpu/drm/i915/display/intel_bios.c >> > @@ -1707,6 +1707,39 @@ static void sanitize_aux_ch(struct intel_bios_encoder_data *devdata, >> > child->aux_channel = 0; >> > } >> > >> > +static u8 dvo_port_type(u8 dvo_port) >> > +{ >> > + switch (dvo_port) { >> > + case DVO_PORT_HDMIA: >> > + case DVO_PORT_HDMIB: >> > + case DVO_PORT_HDMIC: >> > + case DVO_PORT_HDMID: >> > + case DVO_PORT_HDMIE: >> > + case DVO_PORT_HDMIF: >> > + case DVO_PORT_HDMIG: >> > + case DVO_PORT_HDMIH: >> > + case DVO_PORT_HDMII: >> > + return DVO_PORT_HDMIA; >> > + case DVO_PORT_DPA: >> > + case DVO_PORT_DPB: >> > + case DVO_PORT_DPC: >> > + case DVO_PORT_DPD: >> > + case DVO_PORT_DPE: >> > + case DVO_PORT_DPF: >> > + case DVO_PORT_DPG: >> > + case DVO_PORT_DPH: >> > + case DVO_PORT_DPI: >> > + return DVO_PORT_DPA; >> > + case DVO_PORT_MIPIA: >> > + case DVO_PORT_MIPIB: >> > + case DVO_PORT_MIPIC: >> > + case DVO_PORT_MIPID: >> > + return DVO_PORT_MIPIA; >> > + default: >> > + return dvo_port; >> > + } >> > +} >> > + >> > static enum port __dvo_port_to_port(int n_ports, int n_dvo, >> > const int port_mapping[][3], u8 dvo_port) >> > { >> > @@ -2623,35 +2656,17 @@ bool intel_bios_is_port_edp(struct drm_i915_private *i915, enum port port) >> > return false; >> > } >> > >> > -static bool child_dev_is_dp_dual_mode(const struct child_device_config *child, >> > - enum port port) >> > +static bool child_dev_is_dp_dual_mode(const struct child_device_config *child) >> > { >> > - static const struct { >> > - u16 dp, hdmi; >> > - } port_mapping[] = { >> > - /* >> > - * Buggy VBTs may declare DP ports as having >> > - * HDMI type dvo_port :( So let's check both. >> > - */ >> > - [PORT_B] = { DVO_PORT_DPB, DVO_PORT_HDMIB, }, >> > - [PORT_C] = { DVO_PORT_DPC, DVO_PORT_HDMIC, }, >> > - [PORT_D] = { DVO_PORT_DPD, DVO_PORT_HDMID, }, >> > - [PORT_E] = { DVO_PORT_DPE, DVO_PORT_HDMIE, }, >> > - [PORT_F] = { DVO_PORT_DPF, DVO_PORT_HDMIF, }, >> > - }; >> > - >> > - if (port == PORT_A || port >= ARRAY_SIZE(port_mapping)) >> > - return false; >> > - >> > if ((child->device_type & DEVICE_TYPE_DP_DUAL_MODE_BITS) != >> > (DEVICE_TYPE_DP_DUAL_MODE & DEVICE_TYPE_DP_DUAL_MODE_BITS)) >> > return false; >> > >> > - if (child->dvo_port == port_mapping[port].dp) >> > + if (dvo_port_type(child->dvo_port) == DVO_PORT_DPA) >> > return true; >> >> I wonder, why do we care about dvo_port here, while we ignore the dvo >> port DP/HDMI/DSI difference in parse_ddi_port()? I'm not really entirely >> happy about adding another dvo port check method. :/ > > Because VBTs suck and sometimes a DP++ port is declared as DP (as > it should) but sometimes it's declared as HDMI instead. Hence the > additional "do we has aux ch?" check for the dvo_port==HDMI case to > make it at least try not to match native HDMI ports. I'm not sure > whether we could just always do the AUX CH check and ignore the > dvo_port entirely. Would need to look through a bunch of VBTs to > get some idea I suppose. But that would be too much change for a > bugfix anyway. > > IIRC the other idea of just looking at the device_type bits was a > bust on at least vlv/chv. *sad trombone* Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx> The bikeshedding is that I think we should convert child_dev_is_dp_dual_mode() to the same style as the other intel_bios_encoder_supports_*() functions. And we could add the dual mode in "Port %c VBT info" logging in parse_ddi_port() too. In the long run I'd like to ensure encoder->devdata is non-NULL and valid for more platforms, so we could just call intel_bios_encoder_supports_dual_mode(encoder->devdata) directly, so we don't have to loop over ports every time. Anyway, all of this is just musing for future, can be follow-up. BR, Jani. > >> >> > >> > /* Only accept a HDMI dvo_port as DP++ if it has an AUX channel */ >> > - if (child->dvo_port == port_mapping[port].hdmi && >> > + if (dvo_port_type(child->dvo_port) == DVO_PORT_HDMIA && >> > child->aux_channel != 0) >> > return true; >> > >> > @@ -2661,10 +2676,36 @@ static bool child_dev_is_dp_dual_mode(const struct child_device_config *child, >> > bool intel_bios_is_port_dp_dual_mode(struct drm_i915_private *i915, >> > enum port port) >> > { >> > + static const struct { >> > + u16 dp, hdmi; >> > + } port_mapping[] = { >> > + /* >> > + * Buggy VBTs may declare DP ports as having >> > + * HDMI type dvo_port :( So let's check both. >> > + */ >> > + [PORT_B] = { DVO_PORT_DPB, DVO_PORT_HDMIB, }, >> > + [PORT_C] = { DVO_PORT_DPC, DVO_PORT_HDMIC, }, >> > + [PORT_D] = { DVO_PORT_DPD, DVO_PORT_HDMID, }, >> > + [PORT_E] = { DVO_PORT_DPE, DVO_PORT_HDMIE, }, >> > + [PORT_F] = { DVO_PORT_DPF, DVO_PORT_HDMIF, }, >> > + }; >> > const struct intel_bios_encoder_data *devdata; >> > >> > + if (HAS_DDI(i915)) { >> > + const struct intel_bios_encoder_data *devdata; >> > + >> > + devdata = intel_bios_encoder_data_lookup(i915, port); >> > + >> > + return devdata && child_dev_is_dp_dual_mode(&devdata->child); >> > + } >> > + >> > + if (port == PORT_A || port >= ARRAY_SIZE(port_mapping)) >> > + return false; >> > + >> > list_for_each_entry(devdata, &i915->vbt.display_devices, node) { >> > - if (child_dev_is_dp_dual_mode(&devdata->child, port)) >> > + if ((devdata->child.dvo_port == port_mapping[port].dp || >> > + devdata->child.dvo_port == port_mapping[port].hdmi) && >> > + child_dev_is_dp_dual_mode(&devdata->child)) >> > return true; >> > } >> >> -- >> Jani Nikula, Intel Open Source Graphics Center -- Jani Nikula, Intel Open Source Graphics Center
