1 files changed, 29 insertions, 15 deletions

diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.c b/drivers/net/ethernet/intel/igc/igc_tsn.c
index bb10d7b65232..28325dc4fc5b 100644
--- a/drivers/net/ethernet/intel/igc/igc_tsn.c
+++ b/drivers/net/ethernet/intel/igc/igc_tsn.c
@@ -2,6 +2,7 @@
 /* Copyright (c)  2019 Intel Corporation */
 
 #include "igc.h"
+#include "igc_hw.h"
 #include "igc_tsn.h"
 
 static bool is_any_launchtime(struct igc_adapter *adapter)
@@ -92,7 +93,8 @@ static int igc_tsn_disable_offload(struct igc_adapter *adapter)
 
 	tqavctrl = rd32(IGC_TQAVCTRL);
 	tqavctrl &= ~(IGC_TQAVCTRL_TRANSMIT_MODE_TSN |
-		      IGC_TQAVCTRL_ENHANCED_QAV);
+		      IGC_TQAVCTRL_ENHANCED_QAV | IGC_TQAVCTRL_FUTSCDDIS);
+
 	wr32(IGC_TQAVCTRL, tqavctrl);
 
 	for (i = 0; i < adapter->num_tx_queues; i++) {
@@ -117,20 +119,10 @@ static int igc_tsn_enable_offload(struct igc_adapter *adapter)
 	ktime_t base_time, systim;
 	int i;
 
-	cycle = adapter->cycle_time;
-	base_time = adapter->base_time;
-
 	wr32(IGC_TSAUXC, 0);
 	wr32(IGC_DTXMXPKTSZ, IGC_DTXMXPKTSZ_TSN);
 	wr32(IGC_TXPBS, IGC_TXPBSIZE_TSN);
 
-	tqavctrl = rd32(IGC_TQAVCTRL);
-	tqavctrl |= IGC_TQAVCTRL_TRANSMIT_MODE_TSN | IGC_TQAVCTRL_ENHANCED_QAV;
-	wr32(IGC_TQAVCTRL, tqavctrl);
-
-	wr32(IGC_QBVCYCLET_S, cycle);
-	wr32(IGC_QBVCYCLET, cycle);
-
 	for (i = 0; i < adapter->num_tx_queues; i++) {
 		struct igc_ring *ring = adapter->tx_ring[i];
 		u32 txqctl = 0;
@@ -233,21 +225,43 @@ skip_cbs:
 		wr32(IGC_TXQCTL(i), txqctl);
 	}
 
+	tqavctrl = rd32(IGC_TQAVCTRL);
+	tqavctrl |= IGC_TQAVCTRL_TRANSMIT_MODE_TSN | IGC_TQAVCTRL_ENHANCED_QAV;
+
+	cycle = adapter->cycle_time;
+	base_time = adapter->base_time;
+
 	nsec = rd32(IGC_SYSTIML);
 	sec = rd32(IGC_SYSTIMH);
 
 	systim = ktime_set(sec, nsec);
-
 	if (ktime_compare(systim, base_time) > 0) {
-		s64 n;
+		s64 n = div64_s64(ktime_sub_ns(systim, base_time), cycle);
 
-		n = div64_s64(ktime_sub_ns(systim, base_time), cycle);
 		base_time = ktime_add_ns(base_time, (n + 1) * cycle);
+	} else {
+		/* According to datasheet section 7.5.2.9.3.3, FutScdDis bit
+		 * has to be configured before the cycle time and base time.
+		 */
+		if (igc_is_device_id_i226(hw))
+			tqavctrl |= IGC_TQAVCTRL_FUTSCDDIS;
 	}
 
-	baset_h = div_s64_rem(base_time, NSEC_PER_SEC, &baset_l);
+	wr32(IGC_TQAVCTRL, tqavctrl);
+
+	wr32(IGC_QBVCYCLET_S, cycle);
+	wr32(IGC_QBVCYCLET, cycle);
 
+	baset_h = div_s64_rem(base_time, NSEC_PER_SEC, &baset_l);
 	wr32(IGC_BASET_H, baset_h);
+
+	/* In i226, Future base time is only supported when FutScdDis bit
+	 * is enabled and only active for re-configuration.
+	 * In this case, initialize the base time with zero to create
+	 * "re-configuration" scenario then only set the desired base time.
+	 */
+	if (tqavctrl & IGC_TQAVCTRL_FUTSCDDIS)
+		wr32(IGC_BASET_L, 0);
 	wr32(IGC_BASET_L, baset_l);
 
 	return 0;