On Mon, Sep 24, 2018 at 02:08:14PM -0700, Radhakrishna Sripada wrote: > At times 12bpc HDMI cannot be driven due to faulty cables, dongles > level shifters etc. To workaround them we may need to drive the output > at a lower bpc. Currently the user space does not have a way to limit > the bpc. The default bpc to be programmed is decided by the driver and > is run against connector limitations. > > Creating a new connector property "max bpc" in order to limit the bpc. > xrandr can make use of this connector property to make sure that bpc does > not exceed the configured value. This property can be used by userspace to > set the bpc. > > V2: Initialize max_bpc to satisfy kms_properties > V3: Move the property to drm_connector > V4: Split drm and i915 components(Ville) > V5: Make the property per connector(Ville) > V6: Compare the requested bpc to connector bpc(Daniel) > Move the attach_property function to core(Ville) > V7: Fix checkpatch warnings > V8: Simplify the connector check code(Ville) > V9: Const display_info(Ville) > V10: Fix CI issues. > > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> > Cc: Kishore Kadiyala <kishore.kadiyala@xxxxxxxxx> > Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx> > Cc: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx> > Cc: Sunpeng Li <sunpeng.li@xxxxxxx> > Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@xxxxxxxxx> Skimming this, I think it looks good now at a high-level. What's missing is now kernel-doc for these new prorties, needs to be added here: https://dri.freedesktop.org/docs/drm/gpu/drm-kms.html#standard-connector-properties With that I'm happy with the high-level design: Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx> No full review since I didn't look at the igt side for this. Userspace I think is ok, since it's just another connector prop. -Daniel > --- > drivers/gpu/drm/drm_atomic.c | 5 +++++ > drivers/gpu/drm/drm_atomic_helper.c | 4 ++++ > drivers/gpu/drm/drm_atomic_uapi.c | 4 ++++ > drivers/gpu/drm/drm_connector.c | 33 +++++++++++++++++++++++++++++++++ > include/drm/drm_connector.h | 20 ++++++++++++++++++++ > 5 files changed, 66 insertions(+) > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > index 2870ae205237..f328bcca84a8 100644 > --- a/drivers/gpu/drm/drm_atomic.c > +++ b/drivers/gpu/drm/drm_atomic.c > @@ -390,6 +390,7 @@ static int drm_atomic_connector_check(struct drm_connector *connector, > { > struct drm_crtc_state *crtc_state; > struct drm_writeback_job *writeback_job = state->writeback_job; > + const struct drm_display_info *info = &connector->display_info; > > if ((connector->connector_type != DRM_MODE_CONNECTOR_WRITEBACK) || !writeback_job) > return 0; > @@ -417,6 +418,10 @@ static int drm_atomic_connector_check(struct drm_connector *connector, > return -EINVAL; > } > > + state->max_bpc = info->bpc ? info->bpc : 8; > + if (connector->max_bpc_property) > + state->max_bpc = min(state->max_bpc, state->max_requested_bpc); > + > return 0; > } > > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > index e49b22381048..75aeca35f6d9 100644 > --- a/drivers/gpu/drm/drm_atomic_helper.c > +++ b/drivers/gpu/drm/drm_atomic_helper.c > @@ -639,6 +639,10 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, > if (old_connector_state->link_status != > new_connector_state->link_status) > new_crtc_state->connectors_changed = true; > + > + if (old_connector_state->max_requested_bpc != > + new_connector_state->max_requested_bpc) > + new_crtc_state->connectors_changed = true; > } > > if (funcs->atomic_check) > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c > index d5b7f315098c..86ac33922b09 100644 > --- a/drivers/gpu/drm/drm_atomic_uapi.c > +++ b/drivers/gpu/drm/drm_atomic_uapi.c > @@ -740,6 +740,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector, > > return set_out_fence_for_connector(state->state, connector, > fence_ptr); > + } else if (property == connector->max_bpc_property) { > + state->max_requested_bpc = val; > } else if (connector->funcs->atomic_set_property) { > return connector->funcs->atomic_set_property(connector, > state, property, val); > @@ -804,6 +806,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector, > *val = 0; > } else if (property == config->writeback_out_fence_ptr_property) { > *val = 0; > + } else if (property == connector->max_bpc_property) { > + *val = state->max_requested_bpc; > } else if (connector->funcs->atomic_get_property) { > return connector->funcs->atomic_get_property(connector, > state, property, val); > diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c > index 1e40e5decbe9..65e22c1b37a5 100644 > --- a/drivers/gpu/drm/drm_connector.c > +++ b/drivers/gpu/drm/drm_connector.c > @@ -1583,6 +1583,39 @@ void drm_connector_set_link_status_property(struct drm_connector *connector, > EXPORT_SYMBOL(drm_connector_set_link_status_property); > > /** > + * drm_connector_attach_max_bpc_property - attach "max bpc" property > + * @connector: connector to attach max bpc property on. > + * @min: The minimum bit depth supported by the connector. > + * @max: The maximum bit depth supported by the connector. > + * > + * This is used to add support for limiting the bit depth on a connector. > + * > + * Returns: > + * Zero on success, negative errno on failure. > + */ > +int drm_connector_attach_max_bpc_property(struct drm_connector *connector, > + int min, int max) > +{ > + struct drm_device *dev = connector->dev; > + struct drm_property *prop; > + > + prop = connector->max_bpc_property; > + if (!prop) { > + prop = drm_property_create_range(dev, 0, "max bpc", min, max); > + if (!prop) > + return -ENOMEM; > + > + connector->max_bpc_property = prop; > + } > + > + drm_object_attach_property(&connector->base, prop, max); > + connector->state->max_requested_bpc = max; > + > + return 0; > +} > +EXPORT_SYMBOL(drm_connector_attach_max_bpc_property); > + > +/** > * drm_connector_init_panel_orientation_property - > * initialize the connecters panel_orientation property > * @connector: connector for which to init the panel-orientation property. > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h > index 91a877fa00cb..bfc3e698cda6 100644 > --- a/include/drm/drm_connector.h > +++ b/include/drm/drm_connector.h > @@ -461,6 +461,18 @@ struct drm_connector_state { > * drm_writeback_signal_completion() > */ > struct drm_writeback_job *writeback_job; > + > + /** > + * @max_requested_bpc: Connector property to limit the maximum bit > + * depth of the pixels. > + */ > + u8 max_requested_bpc; > + > + /** > + * @max_bpc: Connector max_bpc based on the requested max_bpc property > + * and the connector bpc limitations obtained from edid. > + */ > + u8 max_bpc; > }; > > /** > @@ -924,6 +936,12 @@ struct drm_connector { > */ > struct drm_property_blob *path_blob_ptr; > > + /** > + * @max_bpc_property: Default connector property for the max bpc to be > + * driven out of the connector. > + */ > + struct drm_property *max_bpc_property; > + > #define DRM_CONNECTOR_POLL_HPD (1 << 0) > #define DRM_CONNECTOR_POLL_CONNECT (1 << 1) > #define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2) > @@ -1201,6 +1219,8 @@ void drm_connector_set_link_status_property(struct drm_connector *connector, > uint64_t link_status); > int drm_connector_init_panel_orientation_property( > struct drm_connector *connector, int width, int height); > +int drm_connector_attach_max_bpc_property(struct drm_connector *connector, > + int min, int max); > > /** > * struct drm_tile_group - Tile group metadata > -- > 2.9.3 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
