1 files changed, 95 insertions, 112 deletions

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index ac90118b9e7a..06c91c5b7f7c 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -29,7 +29,6 @@
 #include <linux/random.h>
 #include <linux/sched.h>
 #include <linux/seq_file.h>
-#include <linux/iopoll.h>
 
 #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
 #include <linux/stacktrace.h>
@@ -68,9 +67,6 @@ static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
 
 static void drm_dp_mst_topology_put_port(struct drm_dp_mst_port *port);
 
-static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
-				     int id, u8 start_slot, u8 num_slots);
-
 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
 				 struct drm_dp_mst_port *port,
 				 int offset, int size, u8 *bytes);
@@ -320,6 +316,9 @@ static bool drm_dp_decode_sideband_msg_hdr(const struct drm_dp_mst_topology_mgr
 	hdr->broadcast = (buf[idx] >> 7) & 0x1;
 	hdr->path_msg = (buf[idx] >> 6) & 0x1;
 	hdr->msg_len = buf[idx] & 0x3f;
+	if (hdr->msg_len < 1)		/* min space for body CRC */
+		return false;
+
 	idx++;
 	hdr->somt = (buf[idx] >> 7) & 0x1;
 	hdr->eomt = (buf[idx] >> 6) & 0x1;
@@ -2282,7 +2281,7 @@ drm_dp_mst_port_add_connector(struct drm_dp_mst_branch *mstb,
 		port->cached_edid = drm_edid_read_ddc(port->connector,
 						      &port->aux.ddc);
 
-	drm_connector_register(port->connector);
+	drm_connector_dynamic_register(port->connector);
 	return;
 
 error:
@@ -3264,7 +3263,7 @@ EXPORT_SYMBOL(drm_dp_send_query_stream_enc_status);
 static int drm_dp_create_payload_at_dfp(struct drm_dp_mst_topology_mgr *mgr,
 					struct drm_dp_mst_atomic_payload *payload)
 {
-	return drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot,
+	return drm_dp_dpcd_write_payload(mgr->aux, payload->vcpi, payload->vc_start_slot,
 					 payload->time_slots);
 }
 
@@ -3295,7 +3294,7 @@ static void drm_dp_destroy_payload_at_remote_and_dfp(struct drm_dp_mst_topology_
 	}
 
 	if (payload->payload_allocation_status == DRM_DP_MST_PAYLOAD_ALLOCATION_DFP)
-		drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot, 0);
+		drm_dp_dpcd_write_payload(mgr->aux, payload->vcpi, payload->vc_start_slot, 0);
 }
 
 /**
@@ -3573,8 +3572,7 @@ static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
 }
 
 /**
- * drm_dp_get_vc_payload_bw - get the VC payload BW for an MST link
- * @mgr: The &drm_dp_mst_topology_mgr to use
+ * drm_dp_get_vc_payload_bw - get the VC payload BW for an MTP link
  * @link_rate: link rate in 10kbits/s units
  * @link_lane_count: lane count
  *
@@ -3585,17 +3583,12 @@ static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
  *
  * Returns the BW / timeslot value in 20.12 fixed point format.
  */
-fixed20_12 drm_dp_get_vc_payload_bw(const struct drm_dp_mst_topology_mgr *mgr,
-				    int link_rate, int link_lane_count)
+fixed20_12 drm_dp_get_vc_payload_bw(int link_rate, int link_lane_count)
 {
 	int ch_coding_efficiency =
 		drm_dp_bw_channel_coding_efficiency(drm_dp_is_uhbr_rate(link_rate));
 	fixed20_12 ret;
 
-	if (link_rate == 0 || link_lane_count == 0)
-		drm_dbg_kms(mgr->dev, "invalid link rate/lane count: (%d / %d)\n",
-			    link_rate, link_lane_count);
-
 	/* See DP v2.0 2.6.4.2, 2.7.6.3 VCPayload_Bandwidth_for_OneTimeSlotPer_MTP_Allocation */
 	ret.full = DIV_ROUND_DOWN_ULL(mul_u32_u32(link_rate * link_lane_count,
 						  ch_coding_efficiency),
@@ -3683,7 +3676,7 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms
 			goto out_unlock;
 
 		/* Write reset payload */
-		drm_dp_dpcd_write_payload(mgr, 0, 0, 0x3f);
+		drm_dp_dpcd_clear_payload(mgr->aux);
 
 		drm_dp_mst_queue_probe_work(mgr);
 
@@ -3697,8 +3690,7 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms
 		ret = 0;
 		mgr->payload_id_table_cleared = false;
 
-		memset(&mgr->down_rep_recv, 0, sizeof(mgr->down_rep_recv));
-		memset(&mgr->up_req_recv, 0, sizeof(mgr->up_req_recv));
+		mgr->reset_rx_state = true;
 	}
 
 out_unlock:
@@ -3856,6 +3848,11 @@ out_fail:
 }
 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
 
+static void reset_msg_rx_state(struct drm_dp_sideband_msg_rx *msg)
+{
+	memset(msg, 0, sizeof(*msg));
+}
+
 static bool
 drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
 		      struct drm_dp_mst_branch **mstb)
@@ -3934,6 +3931,34 @@ drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
 	return true;
 }
 
+static int get_msg_request_type(u8 data)
+{
+	return data & 0x7f;
+}
+
+static bool verify_rx_request_type(struct drm_dp_mst_topology_mgr *mgr,
+				   const struct drm_dp_sideband_msg_tx *txmsg,
+				   const struct drm_dp_sideband_msg_rx *rxmsg)
+{
+	const struct drm_dp_sideband_msg_hdr *hdr = &rxmsg->initial_hdr;
+	const struct drm_dp_mst_branch *mstb = txmsg->dst;
+	int tx_req_type = get_msg_request_type(txmsg->msg[0]);
+	int rx_req_type = get_msg_request_type(rxmsg->msg[0]);
+	char rad_str[64];
+
+	if (tx_req_type == rx_req_type)
+		return true;
+
+	drm_dp_mst_rad_to_str(mstb->rad, mstb->lct, rad_str, sizeof(rad_str));
+	drm_dbg_kms(mgr->dev,
+		    "Got unexpected MST reply, mstb: %p seqno: %d lct: %d rad: %s rx_req_type: %s (%02x) != tx_req_type: %s (%02x)\n",
+		    mstb, hdr->seqno, mstb->lct, rad_str,
+		    drm_dp_mst_req_type_str(rx_req_type), rx_req_type,
+		    drm_dp_mst_req_type_str(tx_req_type), tx_req_type);
+
+	return false;
+}
+
 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 {
 	struct drm_dp_sideband_msg_tx *txmsg;
@@ -3949,9 +3974,9 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 
 	/* find the message */
 	mutex_lock(&mgr->qlock);
+
 	txmsg = list_first_entry_or_null(&mgr->tx_msg_downq,
 					 struct drm_dp_sideband_msg_tx, next);
-	mutex_unlock(&mgr->qlock);
 
 	/* Were we actually expecting a response, and from this mstb? */
 	if (!txmsg || txmsg->dst != mstb) {
@@ -3960,6 +3985,15 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 		hdr = &msg->initial_hdr;
 		drm_dbg_kms(mgr->dev, "Got MST reply with no msg %p %d %d %02x %02x\n",
 			    mstb, hdr->seqno, hdr->lct, hdr->rad[0], msg->msg[0]);
+
+		mutex_unlock(&mgr->qlock);
+
+		goto out_clear_reply;
+	}
+
+	if (!verify_rx_request_type(mgr, txmsg, msg)) {
+		mutex_unlock(&mgr->qlock);
+
 		goto out_clear_reply;
 	}
 
@@ -3975,20 +4009,15 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 			    txmsg->reply.u.nak.nak_data);
 	}
 
-	memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx));
-	drm_dp_mst_topology_put_mstb(mstb);
-
-	mutex_lock(&mgr->qlock);
 	txmsg->state = DRM_DP_SIDEBAND_TX_RX;
 	list_del(&txmsg->next);
+
 	mutex_unlock(&mgr->qlock);
 
 	wake_up_all(&mgr->tx_waitq);
 
-	return 0;
-
 out_clear_reply:
-	memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx));
+	reset_msg_rx_state(msg);
 out:
 	if (mstb)
 		drm_dp_mst_topology_put_mstb(mstb);
@@ -4070,16 +4099,20 @@ static void drm_dp_mst_up_req_work(struct work_struct *work)
 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 {
 	struct drm_dp_pending_up_req *up_req;
+	struct drm_dp_mst_branch *mst_primary;
+	int ret = 0;
 
 	if (!drm_dp_get_one_sb_msg(mgr, true, NULL))
-		goto out;
+		goto out_clear_reply;
 
 	if (!mgr->up_req_recv.have_eomt)
 		return 0;
 
 	up_req = kzalloc(sizeof(*up_req), GFP_KERNEL);
-	if (!up_req)
-		return -ENOMEM;
+	if (!up_req) {
+		ret = -ENOMEM;
+		goto out_clear_reply;
+	}
 
 	INIT_LIST_HEAD(&up_req->next);
 
@@ -4090,10 +4123,19 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 		drm_dbg_kms(mgr->dev, "Received unknown up req type, ignoring: %x\n",
 			    up_req->msg.req_type);
 		kfree(up_req);
-		goto out;
+		goto out_clear_reply;
+	}
+
+	mutex_lock(&mgr->lock);
+	mst_primary = mgr->mst_primary;
+	if (!mst_primary || !drm_dp_mst_topology_try_get_mstb(mst_primary)) {
+		mutex_unlock(&mgr->lock);
+		kfree(up_req);
+		goto out_clear_reply;
 	}
+	mutex_unlock(&mgr->lock);
 
-	drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, up_req->msg.req_type,
+	drm_dp_send_up_ack_reply(mgr, mst_primary, up_req->msg.req_type,
 				 false);
 
 	if (up_req->msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
@@ -4110,13 +4152,13 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 			    conn_stat->peer_device_type);
 
 		mutex_lock(&mgr->probe_lock);
-		handle_csn = mgr->mst_primary->link_address_sent;
+		handle_csn = mst_primary->link_address_sent;
 		mutex_unlock(&mgr->probe_lock);
 
 		if (!handle_csn) {
 			drm_dbg_kms(mgr->dev, "Got CSN before finish topology probing. Skip it.");
 			kfree(up_req);
-			goto out;
+			goto out_put_primary;
 		}
 	} else if (up_req->msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
 		const struct drm_dp_resource_status_notify *res_stat =
@@ -4133,9 +4175,22 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 	mutex_unlock(&mgr->up_req_lock);
 	queue_work(system_long_wq, &mgr->up_req_work);
 
-out:
-	memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
-	return 0;
+out_put_primary:
+	drm_dp_mst_topology_put_mstb(mst_primary);
+out_clear_reply:
+	reset_msg_rx_state(&mgr->up_req_recv);
+	return ret;
+}
+
+static void update_msg_rx_state(struct drm_dp_mst_topology_mgr *mgr)
+{
+	mutex_lock(&mgr->lock);
+	if (mgr->reset_rx_state) {
+		mgr->reset_rx_state = false;
+		reset_msg_rx_state(&mgr->down_rep_recv);
+		reset_msg_rx_state(&mgr->up_req_recv);
+	}
+	mutex_unlock(&mgr->lock);
 }
 
 /**
@@ -4172,6 +4227,8 @@ int drm_dp_mst_hpd_irq_handle_event(struct drm_dp_mst_topology_mgr *mgr, const u
 		*handled = true;
 	}
 
+	update_msg_rx_state(mgr);
+
 	if (esi[1] & DP_DOWN_REP_MSG_RDY) {
 		ret = drm_dp_mst_handle_down_rep(mgr);
 		*handled = true;
@@ -4680,61 +4737,6 @@ void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_
 }
 EXPORT_SYMBOL(drm_dp_mst_update_slots);
 
-static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
-				     int id, u8 start_slot, u8 num_slots)
-{
-	u8 payload_alloc[3], status;
-	int ret;
-	int retries = 0;
-
-	drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
-			   DP_PAYLOAD_TABLE_UPDATED);
-
-	payload_alloc[0] = id;
-	payload_alloc[1] = start_slot;
-	payload_alloc[2] = num_slots;
-
-	ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
-	if (ret != 3) {
-		drm_dbg_kms(mgr->dev, "failed to write payload allocation %d\n", ret);
-		goto fail;
-	}
-
-retry:
-	ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
-	if (ret < 0) {
-		drm_dbg_kms(mgr->dev, "failed to read payload table status %d\n", ret);
-		goto fail;
-	}
-
-	if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
-		retries++;
-		if (retries < 20) {
-			usleep_range(10000, 20000);
-			goto retry;
-		}
-		drm_dbg_kms(mgr->dev, "status not set after read payload table status %d\n",
-			    status);
-		ret = -EINVAL;
-		goto fail;
-	}
-	ret = 0;
-fail:
-	return ret;
-}
-
-static int do_get_act_status(struct drm_dp_aux *aux)
-{
-	int ret;
-	u8 status;
-
-	ret = drm_dp_dpcd_readb(aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
-	if (ret < 0)
-		return ret;
-
-	return status;
-}
-
 /**
  * drm_dp_check_act_status() - Polls for ACT handled status.
  * @mgr: manager to use
@@ -4752,28 +4754,9 @@ int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
 	 * There doesn't seem to be any recommended retry count or timeout in
 	 * the MST specification. Since some hubs have been observed to take
 	 * over 1 second to update their payload allocations under certain
-	 * conditions, we use a rather large timeout value.
+	 * conditions, we use a rather large timeout value of 3 seconds.
 	 */
-	const int timeout_ms = 3000;
-	int ret, status;
-
-	ret = readx_poll_timeout(do_get_act_status, mgr->aux, status,
-				 status & DP_PAYLOAD_ACT_HANDLED || status < 0,
-				 200, timeout_ms * USEC_PER_MSEC);
-	if (ret < 0 && status >= 0) {
-		drm_err(mgr->dev, "Failed to get ACT after %dms, last status: %02x\n",
-			timeout_ms, status);
-		return -EINVAL;
-	} else if (status < 0) {
-		/*
-		 * Failure here isn't unexpected - the hub may have
-		 * just been unplugged
-		 */
-		drm_dbg_kms(mgr->dev, "Failed to read payload table status: %d\n", status);
-		return status;
-	}
-
-	return 0;
+	return drm_dp_dpcd_poll_act_handled(mgr->aux, 3000);
 }
 EXPORT_SYMBOL(drm_dp_check_act_status);