On Thu, Jun 05, 2025 at 04:07:15PM +0300, Jani Nikula wrote:
> On Thu, 05 Jun 2025, Imre Deak <imre.d...@intel.com> wrote:
> > Add support for EDID based quirks which can be queried outside of the
> > EDID parser iteself by DRM core and drivers. There are at least two such
> > quirks applicable to all drivers: the DPCD register access probe quirk
> > and the 128b/132b DPRX Lane Count Conversion quirk (see 3.5.2.16.3 in
> > the v2.1a DP Standard). The latter quirk applies to panels with specific
> > EDID panel names, support for defining a quirk this way will be added as
> > a follow-up.
> >
> > v2: Reset global_quirks in drm_reset_display_info().
> > v3: (Jani)
> > - Use one list for both the global and internal quirks.
> > - Drop change for panel name specific quirks.
> > - Add comment about the way quirks should be queried.
> >
> > Cc: Ville Syrjälä <ville.syrj...@linux.intel.com>
> > Cc: Jani Nikula <jani.nik...@linux.intel.com>
> > Signed-off-by: Imre Deak <imre.d...@intel.com>
> > ---
> > drivers/gpu/drm/drm_edid.c | 8 +++++++-
> > include/drm/drm_connector.h | 4 +++-
> > include/drm/drm_edid.h | 5 +++++
> > 3 files changed, 15 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> > index 857ae0c47a1c3..9cca1e6e4736c 100644
> > --- a/drivers/gpu/drm/drm_edid.c
> > +++ b/drivers/gpu/drm/drm_edid.c
> > @@ -68,7 +68,7 @@ static int oui(u8 first, u8 second, u8 third)
> >
> > enum drm_edid_internal_quirk {
> > /* First detailed mode wrong, use largest 60Hz mode */
> > - EDID_QUIRK_PREFER_LARGE_60,
> > + EDID_QUIRK_PREFER_LARGE_60 = DRM_EDID_QUIRK_NUM,
> > /* Reported 135MHz pixel clock is too high, needs adjustment */
> > EDID_QUIRK_135_CLOCK_TOO_HIGH,
> > /* Prefer the largest mode at 75 Hz */
> > @@ -2959,6 +2959,12 @@ static bool drm_edid_has_internal_quirk(struct
> > drm_connector *connector,
> > return connector->display_info.quirks & BIT(quirk);
> > }
> >
> > +bool drm_edid_has_quirk(struct drm_connector *connector, enum
> > drm_edid_quirk quirk)
>
> Nitpick, this could've been const.
I'm unsure what rule to follow for atomic object pointers. Ville said
once that unlike atomic state pointers (i.e. drm_connector_state for
instance) these shouldn't be constified. Maybe that applies only to
cases where the object pointer is passed on to another function (so not
in this simple case clearly)?
> Regardless,
>
> Reviewed-by: Jani Nikula <jani.nik...@intel.com>
>
>
>
> > +{
> > + return connector->display_info.quirks & BIT(quirk);
> > +}
> > +EXPORT_SYMBOL(drm_edid_has_quirk);
> > +
> > #define MODE_SIZE(m) ((m)->hdisplay * (m)->vdisplay)
> > #define MODE_REFRESH_DIFF(c,t) (abs((c) - (t)))
> >
> > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> > index 73903c3c842f3..137773dd138ea 100644
> > --- a/include/drm/drm_connector.h
> > +++ b/include/drm/drm_connector.h
> > @@ -843,7 +843,9 @@ struct drm_display_info {
> > int vics_len;
> >
> > /**
> > - * @quirks: EDID based quirks. Internal to EDID parsing.
> > + * @quirks: EDID based quirks. DRM core and drivers can query the
> > + * @drm_edid_quirk quirks using drm_edid_has_quirk(), the rest of
> > + * the quirks also tracked here are internal to EDID parsing.
> > */
> > u32 quirks;
> >
> > diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
> > index b38409670868d..77fd42608e706 100644
> > --- a/include/drm/drm_edid.h
> > +++ b/include/drm/drm_edid.h
> > @@ -109,6 +109,10 @@ struct detailed_data_string {
> > #define DRM_EDID_CVT_FLAGS_STANDARD_BLANKING (1 << 3)
> > #define DRM_EDID_CVT_FLAGS_REDUCED_BLANKING (1 << 4)
> >
> > +enum drm_edid_quirk {
> > + DRM_EDID_QUIRK_NUM,
> > +};
> > +
> > struct detailed_data_monitor_range {
> > u8 min_vfreq;
> > u8 max_vfreq;
> > @@ -476,5 +480,6 @@ void drm_edid_print_product_id(struct drm_printer *p,
> > u32 drm_edid_get_panel_id(const struct drm_edid *drm_edid);
> > bool drm_edid_match(const struct drm_edid *drm_edid,
> > const struct drm_edid_ident *ident);
> > +bool drm_edid_has_quirk(struct drm_connector *connector, enum
> > drm_edid_quirk quirk);
> >
> > #endif /* __DRM_EDID_H__ */
>
> --
> Jani Nikula, Intel
