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

Kazlauskas, Nicholas Nicholas.Kazlauskas at amd.com
Wed Nov 7 16:56:00 UTC 2018


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>

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

> 
> 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?

> 
>> ---
>>   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 Intel-gfx mailing list