> -----Original Message-----
> From: Nikula, Jani <jani.nikula@xxxxxxxxx>
> Sent: Wednesday, November 9, 2022 5:12 PM
> To: Manna, Animesh <animesh.manna@xxxxxxxxx>; intel-
> gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: Manna, Animesh <animesh.manna@xxxxxxxxx>; Ville Syrjälä
> <ville.syrjala@xxxxxxxxxxxxxxx>; Shankar, Uma <uma.shankar@xxxxxxxxx>
> Subject: Re: [PATCH 2/3] drm/i915/pps: Enable 2nd pps for dual EDP scenario
>
> On Wed, 09 Nov 2022, Animesh Manna <animesh.manna@xxxxxxxxx> wrote:
> > From display gen12 onwards to support dual EDP two instances of pps added.
> > Currently backlight controller and pps instance can be mapped together
> > for a specific panel. Currently dual PPS support is broken. This patch
> > fixes it and enables for display 12+.
> >
> > v1: Iniital revision.
> > v2: Called intel_bios_panel_init w/o PNPID before intel_pps_init.
> > [Jani]
> > v3: Set pps_id to -1 for pnpid type of panel which will be used by
> > bxt_power_sequencer_idx() to set 2nd pps instance as default for 2nd
> > EDP panel. [Jani]
> > v4: Early return for PANEL_TYPE_FALLBACK. [Jani]
> > v5: Removed additional pps_id variable and reused backlight
> > controller. [Jani]
> >
> > Cc: Jani Nikula <jani.nikula@xxxxxxxxx>
> > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> > Cc: Uma Shankar <uma.shankar@xxxxxxxxx>
> > Signed-off-by: Animesh Manna <animesh.manna@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/display/intel_bios.c | 9 ++++++++-
> > drivers/gpu/drm/i915/display/intel_bios.h | 2 +-
> > drivers/gpu/drm/i915/display/intel_dp.c | 10 +++++++---
> > drivers/gpu/drm/i915/display/intel_pps.c | 12 +++++++++++-
> > 4 files changed, 27 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_bios.c
> > b/drivers/gpu/drm/i915/display/intel_bios.c
> > index c2987f2c2b2e..1c1eea061fbb 100644
> > --- a/drivers/gpu/drm/i915/display/intel_bios.c
> > +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> > @@ -3183,7 +3183,7 @@ void intel_bios_init(struct drm_i915_private *i915)
> > kfree(oprom_vbt);
> > }
> >
> > -void intel_bios_init_panel(struct drm_i915_private *i915,
> > +bool intel_bios_init_panel(struct drm_i915_private *i915,
> > struct intel_panel *panel,
> > const struct intel_bios_encoder_data *devdata,
> > const struct edid *edid)
> > @@ -3192,6 +3192,11 @@ void intel_bios_init_panel(struct
> > drm_i915_private *i915,
> >
> > panel->vbt.panel_type = get_panel_type(i915, devdata, edid);
> >
> > + if (panel->vbt.panel_type == PANEL_TYPE_FALLBACK && !edid) {
>
> As Ville pointed out, "panel->vbt.panel_type == PANEL_TYPE_FALLBACK" is
> comparing apples to oranges, and we hit this path only in the rare case that
> panel_type == 3, regardless of where the panel type originated.
Got it, tried returning some random negative number (for example -2) from fallback_get_panel_type() and checking the same here is fixing the WARN_ON.
>
> This is probably the reason patches 1&2 don't fix the original issue like it should.
>
> I remind you that the issue is two eDP having their own pps software states but
> using the same pps hardware due to conflicting pps index (which is the same as
> panel->vbt.backlight.controller). This is what we need to solve here.
In this patch we decide to use the specific pps based on port number. Once we identify it is PORT B always 2nd instance of PPS will be used. All pps register get instantiated with pps_idx 1
if (backlight_controller == -1) {
/*
* Use 2nd PPS instance as default for 2nd EDP panel.
*/
if (connector->encoder->port == PORT_A)
return 0;
else
return 1;
}
Not sure what is toggling the VDD. Anyways I agree patch 3 is not needed. Thanks for review.
Regards,
Animesh
>
> We get the wakeref imbalance because of two eDP trampling on the same pps
> hardware. Patch 3 does nothing to address that issue, it just tries to hide the
> problem.
>
>
> BR,
> Jani.
>
>
> > + panel->vbt.backlight.controller = -1;
> > + return true;
> > + }
> > +
> > parse_panel_options(i915, panel);
> > parse_generic_dtd(i915, panel);
> > parse_lfp_data(i915, panel);
> > @@ -3203,6 +3208,8 @@ void intel_bios_init_panel(struct drm_i915_private
> *i915,
> > parse_psr(i915, panel);
> > parse_mipi_config(i915, panel);
> > parse_mipi_sequence(i915, panel);
> > +
> > + return false;
> > }
> >
> > /**
> > diff --git a/drivers/gpu/drm/i915/display/intel_bios.h
> > b/drivers/gpu/drm/i915/display/intel_bios.h
> > index e375405a7828..f8ef0274f3ee 100644
> > --- a/drivers/gpu/drm/i915/display/intel_bios.h
> > +++ b/drivers/gpu/drm/i915/display/intel_bios.h
> > @@ -232,7 +232,7 @@ struct mipi_pps_data { } __packed;
> >
> > void intel_bios_init(struct drm_i915_private *dev_priv); -void
> > intel_bios_init_panel(struct drm_i915_private *dev_priv,
> > +bool intel_bios_init_panel(struct drm_i915_private *dev_priv,
> > struct intel_panel *panel,
> > const struct intel_bios_encoder_data *devdata,
> > const struct edid *edid);
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> > b/drivers/gpu/drm/i915/display/intel_dp.c
> > index 7400d6b4c587..78cf3a77f026 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -5235,6 +5235,7 @@ static bool intel_edp_init_connector(struct intel_dp
> *intel_dp,
> > struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> > bool has_dpcd;
> > struct edid *edid;
> > + bool retry;
> >
> > if (!intel_dp_is_edp(intel_dp))
> > return true;
> > @@ -5254,6 +5255,9 @@ static bool intel_edp_init_connector(struct intel_dp
> *intel_dp,
> > return false;
> > }
> >
> > + retry = intel_bios_init_panel(dev_priv, &intel_connector->panel,
> > + encoder->devdata, NULL);
> > +
> > intel_pps_init(intel_dp);
> >
> > /* Cache DPCD and EDID for edp. */
> > @@ -5288,9 +5292,9 @@ static bool intel_edp_init_connector(struct intel_dp
> *intel_dp,
> > edid = ERR_PTR(-ENOENT);
> > }
> > intel_connector->edid = edid;
> > -
> > - intel_bios_init_panel(dev_priv, &intel_connector->panel,
> > - encoder->devdata, IS_ERR(edid) ? NULL : edid);
> > + if (retry)
> > + intel_bios_init_panel(dev_priv, &intel_connector->panel,
> > + encoder->devdata, IS_ERR(edid) ? NULL :
> edid);
> >
> > intel_panel_add_edid_fixed_modes(intel_connector, true);
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_pps.c
> > b/drivers/gpu/drm/i915/display/intel_pps.c
> > index 3949fb449353..5738af154bd2 100644
> > --- a/drivers/gpu/drm/i915/display/intel_pps.c
> > +++ b/drivers/gpu/drm/i915/display/intel_pps.c
> > @@ -219,6 +219,16 @@ bxt_power_sequencer_idx(struct intel_dp *intel_dp)
> > /* We should never land here with regular DP ports */
> > drm_WARN_ON(&dev_priv->drm, !intel_dp_is_edp(intel_dp));
> >
> > + if (backlight_controller == -1) {
> > + /*
> > + * Use 2nd PPS instance as default for 2nd EDP panel.
> > + */
> > + if (connector->encoder->port == PORT_A)
> > + return 0;
> > + else
> > + return 1;
> > + }
> > +
> > if (!intel_dp->pps.pps_reset)
> > return backlight_controller;
> >
> > @@ -1430,7 +1440,7 @@ void intel_pps_init(struct intel_dp *intel_dp)
> > intel_dp->pps.initializing = true;
> > INIT_DELAYED_WORK(&intel_dp->pps.panel_vdd_work,
> > edp_panel_vdd_work);
> >
> > - if (IS_GEMINILAKE(i915) || IS_BROXTON(i915))
> > + if (IS_GEMINILAKE(i915) || IS_BROXTON(i915) || DISPLAY_VER(i915) >=
> > +12)
> > intel_dp->get_pps_idx = bxt_power_sequencer_idx;
> > else if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915))
> > intel_dp->get_pps_idx = vlv_power_sequencer_pipe;
>
> --
> Jani Nikula, Intel Open Source Graphics Center
