drm/dp_mst: Remove single tx msg restriction.

Now that we can support multiple simultaneous replies, remove the
restrictions placed on sending new tx msgs.

This patch essentially just reverts commit
  5a64967a2f3b ("drm/dp_mst: Have DP_Tx send one msg at a time")
now that the problem is solved in a different way.

Cc: Wayne Lin <Wayne.Lin@amd.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Wayne Lin <waynelin@amd.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200213211523.156998-4-sean@poorly.run

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 236a4be..840c637 100644 (file)
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1205,8 +1205,6 @@ static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
                    txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
                        mstb->tx_slots[txmsg->seqno] = NULL;
                }
-               mgr->is_waiting_for_dwn_reply = false;
-
        }
 out:
        if (unlikely(ret == -EIO) && drm_debug_enabled(DRM_UT_DP)) {
@@ -1216,7 +1214,6 @@ out:
        }
        mutex_unlock(&mgr->qlock);
 
-       drm_dp_mst_kick_tx(mgr);
        return ret;
 }
 
@@ -2796,11 +2793,9 @@ static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
        ret = process_single_tx_qlock(mgr, txmsg, false);
        if (ret == 1) {
                /* txmsg is sent it should be in the slots now */
-               mgr->is_waiting_for_dwn_reply = true;
                list_del(&txmsg->next);
        } else if (ret) {
                DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
-               mgr->is_waiting_for_dwn_reply = false;
                list_del(&txmsg->next);
                if (txmsg->seqno != -1)
                        txmsg->dst->tx_slots[txmsg->seqno] = NULL;
@@ -2840,8 +2835,7 @@ static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
                drm_dp_mst_dump_sideband_msg_tx(&p, txmsg);
        }
 
-       if (list_is_singular(&mgr->tx_msg_downq) &&
-           !mgr->is_waiting_for_dwn_reply)
+       if (list_is_singular(&mgr->tx_msg_downq))
                process_single_down_tx_qlock(mgr);
        mutex_unlock(&mgr->qlock);
 }
@@ -3828,7 +3822,6 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
        mutex_lock(&mgr->qlock);
        txmsg->state = DRM_DP_SIDEBAND_TX_RX;
        mstb->tx_slots[seqno] = NULL;
-       mgr->is_waiting_for_dwn_reply = false;
        mutex_unlock(&mgr->qlock);
 
        wake_up_all(&mgr->tx_waitq);
@@ -3836,9 +3829,6 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
        return 0;
 
 out_clear_reply:
-       mutex_lock(&mgr->qlock);
-       mgr->is_waiting_for_dwn_reply = false;
-       mutex_unlock(&mgr->qlock);
        if (msg)
                memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx));
 out:
@@ -4696,7 +4686,7 @@ static void drm_dp_tx_work(struct work_struct *work)
        struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
 
        mutex_lock(&mgr->qlock);
-       if (!list_empty(&mgr->tx_msg_downq) && !mgr->is_waiting_for_dwn_reply)
+       if (!list_empty(&mgr->tx_msg_downq))
                process_single_down_tx_qlock(mgr);
        mutex_unlock(&mgr->qlock);
 }

diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index cff1350..bf5e65d 100644 (file)
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -591,11 +591,6 @@ struct drm_dp_mst_topology_mgr {
        bool payload_id_table_cleared : 1;
 
        /**
-        * @is_waiting_for_dwn_reply: whether we're waiting for a down reply.
-        */
-       bool is_waiting_for_dwn_reply : 1;
-
-       /**
         * @mst_primary: Pointer to the primary/first branch device.
         */
        struct drm_dp_mst_branch *mst_primary;