[Intel-gfx] [PATCH v14 1/2] drm: Add connector property to limit max bpc

Rodrigo Vivi rodrigo.vivi at intel.com
Wed Nov 7 18:10:08 UTC 2018


On Wed, Nov 07, 2018 at 04:56:00PM +0000, Kazlauskas, Nicholas wrote:
> On 10/24/18 6:49 PM, Rodrigo Vivi wrote:
> > On Fri, Oct 12, 2018 at 11:42:32AM -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,V11: Fix CI issues.
> >> V12: Add the Kernel documentation(Daniel)
> >> V14: Crossreference the function name in the doc(Daniel)
> >>
> >> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> >> Cc: Kishore Kadiyala <kishore.kadiyala at intel.com>
> >> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> >> Cc: Manasi Navare <manasi.d.navare at intel.com>
> >> Cc: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
> >> Cc: Sunpeng Li <sunpeng.li at amd.com>
> >> Acked-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> >> Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada at intel.com>
> 
> Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>

Thanks. Although I had pushed through drm-intel-next-queued (dinq) already.

> 
> Looks good to me. We're seeing similar issues with > 8bpc that this 
> would help with.

hm... I hope that pushing to dinq doesn't cause any trouble for you :(

> 
> > 
> > This patch looks right to me:
> > 
> > Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > 
> > but we probably need to hold on merge while we wait clarifications
> > and final rv-b on igt tests....
> 
> Any updates on the igt tests?

yeap, RK added the property tests. got reviewed and
merged to igt already as well

Thanks,
Rodrigo.

> 
> > 
> >> ---
> >>   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     | 41 +++++++++++++++++++++++++++++++++++++
> >>   include/drm/drm_connector.h         | 20 ++++++++++++++++++
> >>   5 files changed, 74 insertions(+)
> >>
> >> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> >> index 2870ae205237..cd8362dc4f74 100644
> >> --- a/drivers/gpu/drm/drm_atomic.c
> >> +++ b/drivers/gpu/drm/drm_atomic.c
> >> @@ -390,6 +390,11 @@ 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;
> >> +
> >> +	state->max_bpc = info->bpc ? info->bpc : 8;
> >> +	if (connector->max_bpc_property)
> >> +		state->max_bpc = min(state->max_bpc, state->max_requested_bpc);
> >>   
> >>   	if ((connector->connector_type != DRM_MODE_CONNECTOR_WRITEBACK) || !writeback_job)
> >>   		return 0;
> >> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
> >> index 6f66777dca4b..d61a74b254f5 100644
> >> --- a/drivers/gpu/drm/drm_atomic_helper.c
> >> +++ b/drivers/gpu/drm/drm_atomic_helper.c
> >> @@ -650,6 +650,10 @@ 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 a22d6f269b07..7492819c81ce 100644
> >> --- a/drivers/gpu/drm/drm_atomic_uapi.c
> >> +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> >> @@ -761,6 +761,8 @@ 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);
> >> @@ -825,6 +827,8 @@ 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 5d01414ec9f7..bdaa29e530d4 100644
> >> --- a/drivers/gpu/drm/drm_connector.c
> >> +++ b/drivers/gpu/drm/drm_connector.c
> >> @@ -932,6 +932,13 @@ DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list)
> >>    *	  is no longer protected and userspace should take appropriate action
> >>    *	  (whatever that might be).
> >>    *
> >> + * max bpc:
> >> + *	This range property is used by userspace to limit the bit depth. When
> >> + *	used the driver would limit the bpc in accordance with the valid range
> >> + *	supported by the hardware and sink. Drivers to use the function
> >> + *	drm_connector_attach_max_bpc_property() to create and attach the
> >> + *	property to the connector during initialization.
> >> + *
> >>    * Connectors also have one standardized atomic property:
> >>    *
> >>    * CRTC_ID:
> >> @@ -1600,6 +1607,40 @@ 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;
> >> +	connector->state->max_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 5b3cf909fd5e..a402d16427a1 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)
> >> @@ -1202,6 +1220,8 @@ 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
> >>
> >> _______________________________________________
> >> Intel-gfx mailing list
> >> Intel-gfx at lists.freedesktop.org
> >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> > _______________________________________________
> > dri-devel mailing list
> > dri-devel at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/dri-devel
> > 
> 
> Nicholas Kazlauskas


More information about the dri-devel mailing list