4 files changed, 76 insertions, 16 deletions
diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h b/drivers/net/ethernet/intel/igc/igc_defines.h
index 5f92b3c7c3d4..511384f3ec5c 100644
--- a/drivers/net/ethernet/intel/igc/igc_defines.h
+++ b/drivers/net/ethernet/intel/igc/igc_defines.h
@@ -404,6 +404,12 @@
 #define IGC_DTXMXPKTSZ_TSN	0x19 /* 1600 bytes of max TX DMA packet size */
 #define IGC_DTXMXPKTSZ_DEFAULT	0x98 /* 9728-byte Jumbo frames */
 
+/* Retry Buffer Control */
+#define IGC_RETX_CTL			0x041C
+#define IGC_RETX_CTL_WATERMARK_MASK	0xF
+#define IGC_RETX_CTL_QBVFULLTH_SHIFT	8 /* QBV Retry Buffer Full Threshold */
+#define IGC_RETX_CTL_QBVFULLEN	0x1000 /* Enable QBV Retry Buffer Full Threshold */
+
 /* Transmit Scheduling Latency */
 /* Latency between transmission scheduling (LaunchTime) and the time
  * the packet is transmitted to the network in nanosecond.
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 8daf938afc36..0a095cdea4fb 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -6315,12 +6315,16 @@ static int igc_save_qbv_schedule(struct igc_adapter *adapter,
 	if (!validate_schedule(adapter, qopt))
 		return -EINVAL;
 
+	igc_ptp_read(adapter, &now);
+
+	if (igc_tsn_is_taprio_activated_by_user(adapter) &&
+	    is_base_time_past(qopt->base_time, &now))
+		adapter->qbv_config_change_errors++;
+
 	adapter->cycle_time = qopt->cycle_time;
 	adapter->base_time = qopt->base_time;
 	adapter->taprio_offload_enable = true;
 
-	igc_ptp_read(adapter, &now);
-
 	for (n = 0; n < qopt->num_entries; n++) {
 		struct tc_taprio_sched_entry *e = &qopt->entries[n];
 
@@ -7409,6 +7413,7 @@ static void igc_io_resume(struct pci_dev *pdev)
 	rtnl_lock();
 	if (netif_running(netdev)) {
 		if (igc_open(netdev)) {
+			rtnl_unlock();
 			netdev_err(netdev, "igc_open failed after reset\n");
 			return;
 		}
diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.c b/drivers/net/ethernet/intel/igc/igc_tsn.c
index 22cefb1eeedf..d68fa7f3d5f0 100644
--- a/drivers/net/ethernet/intel/igc/igc_tsn.c
+++ b/drivers/net/ethernet/intel/igc/igc_tsn.c
@@ -49,12 +49,19 @@ static unsigned int igc_tsn_new_flags(struct igc_adapter *adapter)
 	return new_flags;
 }
 
+static bool igc_tsn_is_tx_mode_in_tsn(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+
+	return !!(rd32(IGC_TQAVCTRL) & IGC_TQAVCTRL_TRANSMIT_MODE_TSN);
+}
+
 void igc_tsn_adjust_txtime_offset(struct igc_adapter *adapter)
 {
 	struct igc_hw *hw = &adapter->hw;
 	u16 txoffset;
 
-	if (!is_any_launchtime(adapter))
+	if (!igc_tsn_is_tx_mode_in_tsn(adapter))
 		return;
 
 	switch (adapter->link_speed) {
@@ -78,6 +85,23 @@ void igc_tsn_adjust_txtime_offset(struct igc_adapter *adapter)
 	wr32(IGC_GTXOFFSET, txoffset);
 }
 
+static void igc_tsn_restore_retx_default(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+	u32 retxctl;
+
+	retxctl = rd32(IGC_RETX_CTL) & IGC_RETX_CTL_WATERMARK_MASK;
+	wr32(IGC_RETX_CTL, retxctl);
+}
+
+bool igc_tsn_is_taprio_activated_by_user(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+
+	return (rd32(IGC_BASET_H) || rd32(IGC_BASET_L)) &&
+		adapter->taprio_offload_enable;
+}
+
 /* Returns the TSN specific registers to their default values after
  * the adapter is reset.
  */
@@ -91,6 +115,9 @@ static int igc_tsn_disable_offload(struct igc_adapter *adapter)
 	wr32(IGC_TXPBS, I225_TXPBSIZE_DEFAULT);
 	wr32(IGC_DTXMXPKTSZ, IGC_DTXMXPKTSZ_DEFAULT);
 
+	if (igc_is_device_id_i226(hw))
+		igc_tsn_restore_retx_default(adapter);
+
 	tqavctrl = rd32(IGC_TQAVCTRL);
 	tqavctrl &= ~(IGC_TQAVCTRL_TRANSMIT_MODE_TSN |
 		      IGC_TQAVCTRL_ENHANCED_QAV | IGC_TQAVCTRL_FUTSCDDIS);
@@ -111,6 +138,25 @@ static int igc_tsn_disable_offload(struct igc_adapter *adapter)
 	return 0;
 }
 
+/* To partially fix i226 HW errata, reduce MAC internal buffering from 192 Bytes
+ * to 88 Bytes by setting RETX_CTL register using the recommendation from:
+ * a) Ethernet Controller I225/I226 Specification Update Rev 2.1
+ *    Item 9: TSN: Packet Transmission Might Cross the Qbv Window
+ * b) I225/6 SW User Manual Rev 1.2.4: Section 8.11.5 Retry Buffer Control
+ */
+static void igc_tsn_set_retx_qbvfullthreshold(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+	u32 retxctl, watermark;
+
+	retxctl = rd32(IGC_RETX_CTL);
+	watermark = retxctl & IGC_RETX_CTL_WATERMARK_MASK;
+	/* Set QBVFULLTH value using watermark and set QBVFULLEN */
+	retxctl |= (watermark << IGC_RETX_CTL_QBVFULLTH_SHIFT) |
+		   IGC_RETX_CTL_QBVFULLEN;
+	wr32(IGC_RETX_CTL, retxctl);
+}
+
 static int igc_tsn_enable_offload(struct igc_adapter *adapter)
 {
 	struct igc_hw *hw = &adapter->hw;
@@ -123,6 +169,9 @@ static int igc_tsn_enable_offload(struct igc_adapter *adapter)
 	wr32(IGC_DTXMXPKTSZ, IGC_DTXMXPKTSZ_TSN);
 	wr32(IGC_TXPBS, IGC_TXPBSIZE_TSN);
 
+	if (igc_is_device_id_i226(hw))
+		igc_tsn_set_retx_qbvfullthreshold(adapter);
+
 	for (i = 0; i < adapter->num_tx_queues; i++) {
 		struct igc_ring *ring = adapter->tx_ring[i];
 		u32 txqctl = 0;
@@ -262,14 +311,6 @@ skip_cbs:
 		s64 n = div64_s64(ktime_sub_ns(systim, base_time), cycle);
 
 		base_time = ktime_add_ns(base_time, (n + 1) * cycle);
-
-		/* Increase the counter if scheduling into the past while
-		 * Gate Control List (GCL) is running.
-		 */
-		if ((rd32(IGC_BASET_H) || rd32(IGC_BASET_L)) &&
-		    (adapter->tc_setup_type == TC_SETUP_QDISC_TAPRIO) &&
-		    (adapter->qbv_count > 1))
-			adapter->qbv_config_change_errors++;
 	} else {
 		if (igc_is_device_id_i226(hw)) {
 			ktime_t adjust_time, expires_time;
@@ -331,15 +372,22 @@ int igc_tsn_reset(struct igc_adapter *adapter)
 	return err;
 }
 
-int igc_tsn_offload_apply(struct igc_adapter *adapter)
+static bool igc_tsn_will_tx_mode_change(struct igc_adapter *adapter)
 {
-	struct igc_hw *hw = &adapter->hw;
+	bool any_tsn_enabled = !!(igc_tsn_new_flags(adapter) &
+				  IGC_FLAG_TSN_ANY_ENABLED);
 
-	/* Per I225/6 HW Design Section 7.5.2.1, transmit mode
-	 * cannot be changed dynamically. Require reset the adapter.
+	return (any_tsn_enabled && !igc_tsn_is_tx_mode_in_tsn(adapter)) ||
+	       (!any_tsn_enabled && igc_tsn_is_tx_mode_in_tsn(adapter));
+}
+
+int igc_tsn_offload_apply(struct igc_adapter *adapter)
+{
+	/* Per I225/6 HW Design Section 7.5.2.1 guideline, if tx mode change
+	 * from legacy->tsn or tsn->legacy, then reset adapter is needed.
 	 */
 	if (netif_running(adapter->netdev) &&
-	    (igc_is_device_id_i225(hw) || !adapter->qbv_count)) {
+	    igc_tsn_will_tx_mode_change(adapter)) {
 		schedule_work(&adapter->reset_task);
 		return 0;
 	}
diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.h b/drivers/net/ethernet/intel/igc/igc_tsn.h
index b53e6af560b7..98ec845a86bf 100644
--- a/drivers/net/ethernet/intel/igc/igc_tsn.h
+++ b/drivers/net/ethernet/intel/igc/igc_tsn.h
@@ -7,5 +7,6 @@
 int igc_tsn_offload_apply(struct igc_adapter *adapter);
 int igc_tsn_reset(struct igc_adapter *adapter);
 void igc_tsn_adjust_txtime_offset(struct igc_adapter *adapter);
+bool igc_tsn_is_taprio_activated_by_user(struct igc_adapter *adapter);
 
 #endif /* _IGC_BASE_H */