diff options
| author | Imre Deak <imre.deak@intel.com> | 2023-10-24 03:08:58 +0200 |
|---|---|---|
| committer | Imre Deak <imre.deak@intel.com> | 2023-11-08 16:22:06 +0100 |
| commit | 9dcf67deeab6fbc4984175278b1b2c59881dca52 (patch) | |
| tree | 8880eaa9da095e8f90999ddfc14c10c9ac24fb18 | |
| parent | drm/dp_mst: Fix fractional DSC bpp handling (diff) | |
| download | linux-9dcf67deeab6fbc4984175278b1b2c59881dca52.tar.xz linux-9dcf67deeab6fbc4984175278b1b2c59881dca52.zip | |
drm/dp_mst: Add helper to determine if an MST port is downstream of another port
Add drm_dp_mst_port_downstream_of_parent() required by the i915
driver in a follow-up patch to resolve a BW overallocation of MST
streams going through a given MST port.
Cc: Lyude Paul <lyude@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231030155843.2251023-4-imre.deak@intel.com
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_mst_topology.c | 52 | ||||
| -rw-r--r-- | include/drm/display/drm_dp_mst_helper.h | 3 |
2 files changed, 55 insertions, 0 deletions
diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c index bc2c9dfe229f..fa0049572f22 100644 --- a/drivers/gpu/drm/display/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c @@ -5126,6 +5126,58 @@ static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port, return false; } +static bool +drm_dp_mst_port_downstream_of_parent_locked(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + struct drm_dp_mst_port *parent) +{ + if (!mgr->mst_primary) + return false; + + port = drm_dp_mst_topology_get_port_validated_locked(mgr->mst_primary, + port); + if (!port) + return false; + + if (!parent) + return true; + + parent = drm_dp_mst_topology_get_port_validated_locked(mgr->mst_primary, + parent); + if (!parent) + return false; + + if (!parent->mstb) + return false; + + return drm_dp_mst_port_downstream_of_branch(port, parent->mstb); +} + +/** + * drm_dp_mst_port_downstream_of_parent - check if a port is downstream of a parent port + * @mgr: MST topology manager + * @port: the port being looked up + * @parent: the parent port + * + * The function returns %true if @port is downstream of @parent. If @parent is + * %NULL - denoting the root port - the function returns %true if @port is in + * @mgr's topology. + */ +bool +drm_dp_mst_port_downstream_of_parent(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + struct drm_dp_mst_port *parent) +{ + bool ret; + + mutex_lock(&mgr->lock); + ret = drm_dp_mst_port_downstream_of_parent_locked(mgr, port, parent); + mutex_unlock(&mgr->lock); + + return ret; +} +EXPORT_SYMBOL(drm_dp_mst_port_downstream_of_parent); + static int drm_dp_mst_atomic_check_port_bw_limit(struct drm_dp_mst_port *port, struct drm_dp_mst_topology_state *state); diff --git a/include/drm/display/drm_dp_mst_helper.h b/include/drm/display/drm_dp_mst_helper.h index 655862b3d2a4..e44485aa74e9 100644 --- a/include/drm/display/drm_dp_mst_helper.h +++ b/include/drm/display/drm_dp_mst_helper.h @@ -892,6 +892,9 @@ drm_atomic_get_new_mst_topology_state(struct drm_atomic_state *state, struct drm_dp_mst_atomic_payload * drm_atomic_get_mst_payload_state(struct drm_dp_mst_topology_state *state, struct drm_dp_mst_port *port); +bool drm_dp_mst_port_downstream_of_parent(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + struct drm_dp_mst_port *parent); int __must_check drm_dp_atomic_find_time_slots(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr, |