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authorJason Gunthorpe <jgg@nvidia.com>2021-02-18 11:17:24 -0400
committerJason Gunthorpe <jgg@nvidia.com>2021-02-18 11:19:29 -0400
commit7289e26f395b583f68b676d4d12a0971e4f6f65c (patch)
tree99f8abbb112a3144094e0082dd446439b930beea /drivers/gpu/drm/drm_dp_mst_topology.c
parented408529679737a9a7ad816c8de5d59ba104bb11 (diff)
parentf40ddce88593482919761f74910f42f4b84c004b (diff)
Merge tag 'v5.11' into rdma.git for-next
Linux 5.11 Merged to resolve conflicts with RDMA rc commits - drivers/infiniband/sw/rxe/rxe_net.c The final logic is to call rxe_get_dev_from_net() again with the master netdev if the packet was rx'd on a vlan. To keep the elimination of the local variables requires a trivial edit to the code in -rc Link: https://lore.kernel.org/r/20210210131542.215ea67c@canb.auug.org.au Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'drivers/gpu/drm/drm_dp_mst_topology.c')
-rw-r--r--drivers/gpu/drm/drm_dp_mst_topology.c25
1 files changed, 19 insertions, 6 deletions
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 0401b2f47500..b11c0522a441 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3629,14 +3629,26 @@ static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
return 0;
}
-static int drm_dp_get_vc_payload_bw(u8 dp_link_bw, u8 dp_link_count)
+/**
+ * drm_dp_get_vc_payload_bw - get the VC payload BW for an MST link
+ * @link_rate: link rate in 10kbits/s units
+ * @link_lane_count: lane count
+ *
+ * Calculate the total bandwidth of a MultiStream Transport link. The returned
+ * value is in units of PBNs/(timeslots/1 MTP). This value can be used to
+ * convert the number of PBNs required for a given stream to the number of
+ * timeslots this stream requires in each MTP.
+ */
+int drm_dp_get_vc_payload_bw(int link_rate, int link_lane_count)
{
- if (dp_link_bw == 0 || dp_link_count == 0)
- DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
- dp_link_bw, dp_link_count);
+ if (link_rate == 0 || link_lane_count == 0)
+ DRM_DEBUG_KMS("invalid link rate/lane count: (%d / %d)\n",
+ link_rate, link_lane_count);
- return dp_link_bw * dp_link_count / 2;
+ /* See DP v2.0 2.6.4.2, VCPayload_Bandwidth_for_OneTimeSlotPer_MTP_Allocation */
+ return link_rate * link_lane_count / 54000;
}
+EXPORT_SYMBOL(drm_dp_get_vc_payload_bw);
/**
* drm_dp_read_mst_cap() - check whether or not a sink supports MST
@@ -3692,7 +3704,7 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms
goto out_unlock;
}
- mgr->pbn_div = drm_dp_get_vc_payload_bw(mgr->dpcd[1],
+ mgr->pbn_div = drm_dp_get_vc_payload_bw(drm_dp_bw_code_to_link_rate(mgr->dpcd[1]),
mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK);
if (mgr->pbn_div == 0) {
ret = -EINVAL;
@@ -4212,6 +4224,7 @@ drm_dp_mst_detect_port(struct drm_connector *connector,
switch (port->pdt) {
case DP_PEER_DEVICE_NONE:
+ break;
case DP_PEER_DEVICE_MST_BRANCHING:
if (!port->mcs)
ret = connector_status_connected;