| Message ID | 20180326214456.6655-30-niklas.soderlund+renesas@ragnatech.se (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Niklas, Thank you for the patch. On Tuesday, 27 March 2018 00:44:52 EEST Niklas Söderlund wrote: > Add the ability to process media device link change requests. Link > enabling is a bit complicated on Gen3, whether or not it's possible to > enable a link depends on what other links already are enabled. On Gen3 > the 8 VINs are split into two subgroup's (VIN0-3 and VIN4-7) and from a > routing perspective these two groups are independent of each other. > Each subgroup's routing is controlled by the subgroup VIN master > instance (VIN0 and VIN4). > > There are a limited number of possible route setups available for each > subgroup and the configuration of each setup is dictated by the > hardware. On H3 for example there are 6 possible route setups for each > subgroup to choose from. > > This leads to the media device link notification code being rather large > since it will find the best routing configuration to try and accommodate > as many links as possible. When it's not possible to enable a new link > due to hardware constrains the link_notifier callback will return > -EMLINK. > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> > Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > > --- > > * Changes since v11 > - Fixed spelling > - Updated comment to clarify the intent that no link can be enabled if > any video node is open. > - Use container_of() instead of a loop to find struct vin_dev from the > video device. > --- > drivers/media/platform/rcar-vin/rcar-core.c | 147 > ++++++++++++++++++++++++++++ 1 file changed, 147 insertions(+) > > diff --git a/drivers/media/platform/rcar-vin/rcar-core.c > b/drivers/media/platform/rcar-vin/rcar-core.c index > 99f6301a778046df..0cc76d73115e9277 100644 > --- a/drivers/media/platform/rcar-vin/rcar-core.c > +++ b/drivers/media/platform/rcar-vin/rcar-core.c > @@ -24,6 +24,7 @@ > > #include <media/v4l2-async.h> > #include <media/v4l2-fwnode.h> > +#include <media/v4l2-mc.h> > > #include "rcar-vin.h" > > @@ -44,6 +45,151 @@ > */ > #define rvin_group_id_to_master(vin) ((vin) < 4 ? 0 : 4) > > +/* > --------------------------------------------------------------------------- > -- + * Media Controller link notification > + */ > + > +/* group lock should be held when calling this function. */ > +static int rvin_group_entity_to_csi_id(struct rvin_group *group, > + struct media_entity *entity) > +{ > + struct v4l2_subdev *sd; > + unsigned int i; > + > + sd = media_entity_to_v4l2_subdev(entity); > + > + for (i = 0; i < RVIN_CSI_MAX; i++) > + if (group->csi[i].subdev == sd) > + return i; > + > + return -ENODEV; > +} > + > +static unsigned int rvin_group_get_mask(struct rvin_dev *vin, > + enum rvin_csi_id csi_id, > + unsigned char channel) > +{ > + const struct rvin_group_route *route; > + unsigned int mask = 0; > + > + for (route = vin->info->routes; route->mask; route++) { > + if (route->vin == vin->id && > + route->csi == csi_id && > + route->channel == channel) { > + vin_dbg(vin, > + "Adding route: vin: %d csi: %d channel: %d\n", > + route->vin, route->csi, route->channel); > + mask |= route->mask; > + } > + } > + > + return mask; > +} > + > +/* > + * Link setup for the links between a VIN and a CSI-2 receiver is a bit > + * complex. The reason for this is that the register controlling routing > + * is not present in each VIN instance. There are special VINs which > + * control routing for themselves and other VINs. There are not many > + * different possible links combinations that can be enabled at the same > + * time, therefor all already enabled links which are controlled by a > + * master VIN need to be taken into account when making the decision > + * if a new link can be enabled or not. > + * > + * 1. Find out which VIN the link the user tries to enable is connected to. > + * 2. Lookup which master VIN controls the links for this VIN. > + * 3. Start with a bitmask with all bits set. > + * 4. For each previously enabled link from the master VIN bitwise AND its > + * route mask (see documentation for mask in struct rvin_group_route) > + * with the bitmask. > + * 5. Bitwise AND the mask for the link the user tries to enable to the > bitmask. + * 6. If the bitmask is not empty at this point the new link can > be enabled + * while keeping all previous links enabled. Update the > CHSEL value of the + * master VIN and inform the user that the link > could be enabled. + * > + * Please note that no link can be enabled if any VIN in the group is > + * currently open. > + */ > +static int rvin_group_link_notify(struct media_link *link, u32 flags, > + unsigned int notification) > +{ > + struct rvin_group *group = container_of(link->graph_obj.mdev, > + struct rvin_group, mdev); > + unsigned int master_id, channel, mask_new, i; > + unsigned int mask = ~0; > + struct media_entity *entity; > + struct video_device *vdev; > + struct media_pad *csi_pad; > + struct rvin_dev *vin = NULL; > + int csi_id, ret; > + > + ret = v4l2_pipeline_link_notify(link, flags, notification); > + if (ret) > + return ret; > + > + /* Only care about link enablement for VIN nodes. */ > + if (!(flags & MEDIA_LNK_FL_ENABLED) || > + !is_media_entity_v4l2_video_device(link->sink->entity)) > + return 0; > + > + /* If any entity is in use don't allow link changes. */ > + media_device_for_each_entity(entity, &group->mdev) > + if (entity->use_count) > + return -EBUSY; > + > + mutex_lock(&group->lock); > + > + /* Find the master VIN that controls the routes. */ > + vdev = media_entity_to_video_device(link->sink->entity); > + vin = container_of(vdev, struct rvin_dev, vdev); > + master_id = rvin_group_id_to_master(vin->id); > + > + if (WARN_ON(!group->vin[master_id])) { > + ret = -ENODEV; > + goto out; > + } > + > + /* Build a mask for already enabled links. */ > + for (i = master_id; i < master_id + 4; i++) { > + if (!group->vin[i]) > + continue; > + > + /* Get remote CSI-2, if any. */ > + csi_pad = media_entity_remote_pad( > + &group->vin[i]->vdev.entity.pads[0]); > + if (!csi_pad) > + continue; > + > + csi_id = rvin_group_entity_to_csi_id(group, csi_pad->entity); > + channel = rvin_group_csi_pad_to_channel(csi_pad->index); > + > + mask &= rvin_group_get_mask(group->vin[i], csi_id, channel); > + } > + > + /* Add the new link to the existing mask and check if it works. */ > + csi_id = rvin_group_entity_to_csi_id(group, link->source->entity); > + channel = rvin_group_csi_pad_to_channel(link->source->index); > + mask_new = mask & rvin_group_get_mask(vin, csi_id, channel); > + > + vin_dbg(vin, "Try link change mask: 0x%x new: 0x%x\n", mask, mask_new); > + > + if (!mask_new) { > + ret = -EMLINK; > + goto out; > + } > + > + /* New valid CHSEL found, set the new value. */ > + ret = rvin_set_channel_routing(group->vin[master_id], __ffs(mask_new)); > +out: > + mutex_unlock(&group->lock); > + > + return ret; > +} > + > +static const struct media_device_ops rvin_media_ops = { > + .link_notify = rvin_group_link_notify, > +}; > + > /* > --------------------------------------------------------------------------- > -- * Gen3 CSI2 Group Allocator > */ > @@ -85,6 +231,7 @@ static int rvin_group_init(struct rvin_group *group, > struct rvin_dev *vin) vin_dbg(vin, "found %u enabled VIN's in DT", > group->count); > > mdev->dev = vin->dev; > + mdev->ops = &rvin_media_ops; > > match = of_match_node(vin->dev->driver->of_match_table, > vin->dev->of_node);
diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c index 99f6301a778046df..0cc76d73115e9277 100644 --- a/drivers/media/platform/rcar-vin/rcar-core.c +++ b/drivers/media/platform/rcar-vin/rcar-core.c @@ -24,6 +24,7 @@ #include <media/v4l2-async.h> #include <media/v4l2-fwnode.h> +#include <media/v4l2-mc.h> #include "rcar-vin.h" @@ -44,6 +45,151 @@ */ #define rvin_group_id_to_master(vin) ((vin) < 4 ? 0 : 4) +/* ----------------------------------------------------------------------------- + * Media Controller link notification + */ + +/* group lock should be held when calling this function. */ +static int rvin_group_entity_to_csi_id(struct rvin_group *group, + struct media_entity *entity) +{ + struct v4l2_subdev *sd; + unsigned int i; + + sd = media_entity_to_v4l2_subdev(entity); + + for (i = 0; i < RVIN_CSI_MAX; i++) + if (group->csi[i].subdev == sd) + return i; + + return -ENODEV; +} + +static unsigned int rvin_group_get_mask(struct rvin_dev *vin, + enum rvin_csi_id csi_id, + unsigned char channel) +{ + const struct rvin_group_route *route; + unsigned int mask = 0; + + for (route = vin->info->routes; route->mask; route++) { + if (route->vin == vin->id && + route->csi == csi_id && + route->channel == channel) { + vin_dbg(vin, + "Adding route: vin: %d csi: %d channel: %d\n", + route->vin, route->csi, route->channel); + mask |= route->mask; + } + } + + return mask; +} + +/* + * Link setup for the links between a VIN and a CSI-2 receiver is a bit + * complex. The reason for this is that the register controlling routing + * is not present in each VIN instance. There are special VINs which + * control routing for themselves and other VINs. There are not many + * different possible links combinations that can be enabled at the same + * time, therefor all already enabled links which are controlled by a + * master VIN need to be taken into account when making the decision + * if a new link can be enabled or not. + * + * 1. Find out which VIN the link the user tries to enable is connected to. + * 2. Lookup which master VIN controls the links for this VIN. + * 3. Start with a bitmask with all bits set. + * 4. For each previously enabled link from the master VIN bitwise AND its + * route mask (see documentation for mask in struct rvin_group_route) + * with the bitmask. + * 5. Bitwise AND the mask for the link the user tries to enable to the bitmask. + * 6. If the bitmask is not empty at this point the new link can be enabled + * while keeping all previous links enabled. Update the CHSEL value of the + * master VIN and inform the user that the link could be enabled. + * + * Please note that no link can be enabled if any VIN in the group is + * currently open. + */ +static int rvin_group_link_notify(struct media_link *link, u32 flags, + unsigned int notification) +{ + struct rvin_group *group = container_of(link->graph_obj.mdev, + struct rvin_group, mdev); + unsigned int master_id, channel, mask_new, i; + unsigned int mask = ~0; + struct media_entity *entity; + struct video_device *vdev; + struct media_pad *csi_pad; + struct rvin_dev *vin = NULL; + int csi_id, ret; + + ret = v4l2_pipeline_link_notify(link, flags, notification); + if (ret) + return ret; + + /* Only care about link enablement for VIN nodes. */ + if (!(flags & MEDIA_LNK_FL_ENABLED) || + !is_media_entity_v4l2_video_device(link->sink->entity)) + return 0; + + /* If any entity is in use don't allow link changes. */ + media_device_for_each_entity(entity, &group->mdev) + if (entity->use_count) + return -EBUSY; + + mutex_lock(&group->lock); + + /* Find the master VIN that controls the routes. */ + vdev = media_entity_to_video_device(link->sink->entity); + vin = container_of(vdev, struct rvin_dev, vdev); + master_id = rvin_group_id_to_master(vin->id); + + if (WARN_ON(!group->vin[master_id])) { + ret = -ENODEV; + goto out; + } + + /* Build a mask for already enabled links. */ + for (i = master_id; i < master_id + 4; i++) { + if (!group->vin[i]) + continue; + + /* Get remote CSI-2, if any. */ + csi_pad = media_entity_remote_pad( + &group->vin[i]->vdev.entity.pads[0]); + if (!csi_pad) + continue; + + csi_id = rvin_group_entity_to_csi_id(group, csi_pad->entity); + channel = rvin_group_csi_pad_to_channel(csi_pad->index); + + mask &= rvin_group_get_mask(group->vin[i], csi_id, channel); + } + + /* Add the new link to the existing mask and check if it works. */ + csi_id = rvin_group_entity_to_csi_id(group, link->source->entity); + channel = rvin_group_csi_pad_to_channel(link->source->index); + mask_new = mask & rvin_group_get_mask(vin, csi_id, channel); + + vin_dbg(vin, "Try link change mask: 0x%x new: 0x%x\n", mask, mask_new); + + if (!mask_new) { + ret = -EMLINK; + goto out; + } + + /* New valid CHSEL found, set the new value. */ + ret = rvin_set_channel_routing(group->vin[master_id], __ffs(mask_new)); +out: + mutex_unlock(&group->lock); + + return ret; +} + +static const struct media_device_ops rvin_media_ops = { + .link_notify = rvin_group_link_notify, +}; + /* ----------------------------------------------------------------------------- * Gen3 CSI2 Group Allocator */ @@ -85,6 +231,7 @@ static int rvin_group_init(struct rvin_group *group, struct rvin_dev *vin) vin_dbg(vin, "found %u enabled VIN's in DT", group->count); mdev->dev = vin->dev; + mdev->ops = &rvin_media_ops; match = of_match_node(vin->dev->driver->of_match_table, vin->dev->of_node);