Merge branch 'intel-next-queue-1GbE'

Tony Nguyen says:

====================
Faizal Rahim says:

MAC Merge support for frame preemption was previously added for igc:
https://lore.kernel.org/netdev/20250418163822.3519810-1-anthony.l.nguyen@intel.com/

This series builds on that work and adds support for:
- Harmonizing taprio and mqprio queue priority behavior, based on past
  discussions and suggestions:
  https://lore.kernel.org/all/20250214102206.25dqgut5tbak2rkz@skbuf/
- Enabling preemptible queue support for both taprio and mqprio, with
  priority harmonization as a prerequisite.

Patch organization:
- Patches 1-3: Preparation work for patches 6 and 7
- Patches 4-5: Queue priority harmonization
- Patches 6-7: Add preemptible queue support
====================

Link: https://patch.msgid.link/20250611180314.2059166-1-anthony.l.nguyen@intel.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

7 files changed, 189 insertions, 43 deletions

diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
index 859a15e4ccba..1525ae25fd3e 100644
--- a/drivers/net/ethernet/intel/igc/igc.h
+++ b/drivers/net/ethernet/intel/igc/igc.h
@@ -43,6 +43,7 @@ void igc_ethtool_set_ops(struct net_device *);
 struct igc_fpe_t {
 	struct ethtool_mmsv mmsv;
 	u32 tx_min_frag_size;
+	bool tx_enabled;
 };
 
 enum igc_mac_filter_type {
@@ -163,6 +164,7 @@ struct igc_ring {
 	bool launchtime_enable;         /* true if LaunchTime is enabled */
 	ktime_t last_tx_cycle;          /* end of the cycle with a launchtime transmission */
 	ktime_t last_ff_cycle;          /* Last cycle with an active first flag */
+	bool preemptible;		/* True if preemptible queue, false if express queue */
 
 	u32 start_time;
 	u32 end_time;
@@ -395,6 +397,7 @@ extern char igc_driver_name[];
 #define IGC_FLAG_TSN_QBV_ENABLED	BIT(17)
 #define IGC_FLAG_TSN_QAV_ENABLED	BIT(18)
 #define IGC_FLAG_TSN_PREEMPT_ENABLED	BIT(19)
+#define IGC_FLAG_TSN_REVERSE_TXQ_PRIO	BIT(20)
 
 #define IGC_FLAG_TSN_ANY_ENABLED				\
 	(IGC_FLAG_TSN_QBV_ENABLED | IGC_FLAG_TSN_QAV_ENABLED |	\
@@ -485,12 +488,30 @@ static inline u32 igc_rss_type(const union igc_adv_rx_desc *rx_desc)
  *           descriptors until either it has this many to write back, or the
  *           ITR timer expires.
  */
-#define IGC_RX_PTHRESH			8
-#define IGC_RX_HTHRESH			8
-#define IGC_TX_PTHRESH			8
-#define IGC_TX_HTHRESH			1
-#define IGC_RX_WTHRESH			4
-#define IGC_TX_WTHRESH			16
+#define IGC_RXDCTL_PTHRESH		8
+#define IGC_RXDCTL_HTHRESH		8
+#define IGC_RXDCTL_WTHRESH		4
+/* Ena specific Rx Queue */
+#define IGC_RXDCTL_QUEUE_ENABLE		0x02000000
+/* Receive Software Flush */
+#define IGC_RXDCTL_SWFLUSH		0x04000000
+
+#define IGC_TXDCTL_PTHRESH_MASK		GENMASK(4, 0)
+#define IGC_TXDCTL_HTHRESH_MASK		GENMASK(12, 8)
+#define IGC_TXDCTL_WTHRESH_MASK		GENMASK(20, 16)
+#define IGC_TXDCTL_QUEUE_ENABLE_MASK	GENMASK(25, 25)
+#define IGC_TXDCTL_SWFLUSH_MASK		GENMASK(26, 26)
+#define IGC_TXDCTL_PRIORITY_MASK	GENMASK(27, 27)
+
+#define IGC_TXDCTL_PTHRESH(x)		FIELD_PREP(IGC_TXDCTL_PTHRESH_MASK, (x))
+#define IGC_TXDCTL_HTHRESH(x)		FIELD_PREP(IGC_TXDCTL_HTHRESH_MASK, (x))
+#define IGC_TXDCTL_WTHRESH(x)		FIELD_PREP(IGC_TXDCTL_WTHRESH_MASK, (x))
+/* Ena specific Tx Queue */
+#define IGC_TXDCTL_QUEUE_ENABLE		FIELD_PREP(IGC_TXDCTL_QUEUE_ENABLE_MASK, 1)
+/* Transmit Software Flush */
+#define IGC_TXDCTL_SWFLUSH		FIELD_PREP(IGC_TXDCTL_SWFLUSH_MASK, 1)
+#define IGC_TXDCTL_PRIORITY(x)		FIELD_PREP(IGC_TXDCTL_PRIORITY_MASK, (x))
+#define IGC_TXDCTL_PRIORITY_HIGH	IGC_TXDCTL_PRIORITY(1)
 
 #define IGC_RX_DMA_ATTR \
 	(DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING)
diff --git a/drivers/net/ethernet/intel/igc/igc_base.h b/drivers/net/ethernet/intel/igc/igc_base.h
index 6320eabb72fe..eaf17cd031c3 100644
--- a/drivers/net/ethernet/intel/igc/igc_base.h
+++ b/drivers/net/ethernet/intel/igc/igc_base.h
@@ -86,14 +86,6 @@ union igc_adv_rx_desc {
 	} wb;  /* writeback */
 };
 
-/* Additional Transmit Descriptor Control definitions */
-#define IGC_TXDCTL_QUEUE_ENABLE	0x02000000 /* Ena specific Tx Queue */
-#define IGC_TXDCTL_SWFLUSH	0x04000000 /* Transmit Software Flush */
-
-/* Additional Receive Descriptor Control definitions */
-#define IGC_RXDCTL_QUEUE_ENABLE	0x02000000 /* Ena specific Rx Queue */
-#define IGC_RXDCTL_SWFLUSH		0x04000000 /* Receive Software Flush */
-
 /* SRRCTL bit definitions */
 #define IGC_SRRCTL_BSIZEPKT_MASK	GENMASK(6, 0)
 #define IGC_SRRCTL_BSIZEPKT(x)		FIELD_PREP(IGC_SRRCTL_BSIZEPKT_MASK, \
diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h b/drivers/net/ethernet/intel/igc/igc_defines.h
index 7189dfc389ad..86b346687196 100644
--- a/drivers/net/ethernet/intel/igc/igc_defines.h
+++ b/drivers/net/ethernet/intel/igc/igc_defines.h
@@ -588,6 +588,7 @@
 #define IGC_TXQCTL_QUEUE_MODE_LAUNCHT	0x00000001
 #define IGC_TXQCTL_STRICT_CYCLE		0x00000002
 #define IGC_TXQCTL_STRICT_END		0x00000004
+#define IGC_TXQCTL_PREEMPTIBLE		0x00000008
 #define IGC_TXQCTL_QAV_SEL_MASK		0x000000C0
 #define IGC_TXQCTL_QAV_SEL_CBS0		0x00000080
 #define IGC_TXQCTL_QAV_SEL_CBS1		0x000000C0
diff --git a/drivers/net/ethernet/intel/igc/igc_ethtool.c b/drivers/net/ethernet/intel/igc/igc_ethtool.c
index e6cac8d4b862..a7f397b58cd6 100644
--- a/drivers/net/ethernet/intel/igc/igc_ethtool.c
+++ b/drivers/net/ethernet/intel/igc/igc_ethtool.c
@@ -122,9 +122,11 @@ static const char igc_gstrings_test[][ETH_GSTRING_LEN] = {
 #define IGC_STATS_LEN \
 	(IGC_GLOBAL_STATS_LEN + IGC_NETDEV_STATS_LEN + IGC_QUEUE_STATS_LEN)
 
+#define IGC_PRIV_FLAGS_LEGACY_RX		BIT(0)
+#define IGC_PRIV_FLAGS_REVERSE_TSN_TXQ_PRIO	BIT(1)
 static const char igc_priv_flags_strings[][ETH_GSTRING_LEN] = {
-#define IGC_PRIV_FLAGS_LEGACY_RX	BIT(0)
 	"legacy-rx",
+	"reverse-tsn-txq-prio",
 };
 
 #define IGC_PRIV_FLAGS_STR_LEN ARRAY_SIZE(igc_priv_flags_strings)
@@ -1600,6 +1602,9 @@ static u32 igc_ethtool_get_priv_flags(struct net_device *netdev)
 	if (adapter->flags & IGC_FLAG_RX_LEGACY)
 		priv_flags |= IGC_PRIV_FLAGS_LEGACY_RX;
 
+	if (adapter->flags & IGC_FLAG_TSN_REVERSE_TXQ_PRIO)
+		priv_flags |= IGC_PRIV_FLAGS_REVERSE_TSN_TXQ_PRIO;
+
 	return priv_flags;
 }
 
@@ -1608,10 +1613,13 @@ static int igc_ethtool_set_priv_flags(struct net_device *netdev, u32 priv_flags)
 	struct igc_adapter *adapter = netdev_priv(netdev);
 	unsigned int flags = adapter->flags;
 
-	flags &= ~IGC_FLAG_RX_LEGACY;
+	flags &= ~(IGC_FLAG_RX_LEGACY | IGC_FLAG_TSN_REVERSE_TXQ_PRIO);
 	if (priv_flags & IGC_PRIV_FLAGS_LEGACY_RX)
 		flags |= IGC_FLAG_RX_LEGACY;
 
+	if (priv_flags & IGC_PRIV_FLAGS_REVERSE_TSN_TXQ_PRIO)
+		flags |= IGC_FLAG_TSN_REVERSE_TXQ_PRIO;
+
 	if (flags != adapter->flags) {
 		adapter->flags = flags;
 
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 686793c539f2..2e12915b42a9 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -683,9 +683,9 @@ static void igc_configure_rx_ring(struct igc_adapter *adapter,
 
 	wr32(IGC_SRRCTL(reg_idx), srrctl);
 
-	rxdctl |= IGC_RX_PTHRESH;
-	rxdctl |= IGC_RX_HTHRESH << 8;
-	rxdctl |= IGC_RX_WTHRESH << 16;
+	rxdctl |= IGC_RXDCTL_PTHRESH;
+	rxdctl |= IGC_RXDCTL_HTHRESH << 8;
+	rxdctl |= IGC_RXDCTL_WTHRESH << 16;
 
 	/* initialize rx_buffer_info */
 	memset(ring->rx_buffer_info, 0,
@@ -749,11 +749,9 @@ static void igc_configure_tx_ring(struct igc_adapter *adapter,
 	wr32(IGC_TDH(reg_idx), 0);
 	writel(0, ring->tail);
 
-	txdctl |= IGC_TX_PTHRESH;
-	txdctl |= IGC_TX_HTHRESH << 8;
-	txdctl |= IGC_TX_WTHRESH << 16;
+	txdctl |= IGC_TXDCTL_PTHRESH(8) | IGC_TXDCTL_HTHRESH(1) |
+		  IGC_TXDCTL_WTHRESH(16) | IGC_TXDCTL_QUEUE_ENABLE;
 
-	txdctl |= IGC_TXDCTL_QUEUE_ENABLE;
 	wr32(IGC_TXDCTL(reg_idx), txdctl);
 }
 
@@ -1687,6 +1685,15 @@ done:
 	first->tx_flags = tx_flags;
 	first->protocol = protocol;
 
+	/* For preemptible queue, manually pad the skb so that HW includes
+	 * padding bytes in mCRC calculation
+	 */
+	if (tx_ring->preemptible && skb->len < ETH_ZLEN) {
+		if (skb_padto(skb, ETH_ZLEN))
+			goto out_drop;
+		skb_put(skb, ETH_ZLEN - skb->len);
+	}
+
 	tso = igc_tso(tx_ring, first, launch_time, first_flag, &hdr_len);
 	if (tso < 0)
 		goto out_drop;
@@ -6423,6 +6430,7 @@ static int igc_qbv_clear_schedule(struct igc_adapter *adapter)
 		ring->start_time = 0;
 		ring->end_time = NSEC_PER_SEC;
 		ring->max_sdu = 0;
+		ring->preemptible = false;
 	}
 
 	spin_lock_irqsave(&adapter->qbv_tx_lock, flags);
@@ -6488,9 +6496,12 @@ static int igc_save_qbv_schedule(struct igc_adapter *adapter,
 	if (!validate_schedule(adapter, qopt))
 		return -EINVAL;
 
-	/* preemptible isn't supported yet */
-	if (qopt->mqprio.preemptible_tcs)
-		return -EOPNOTSUPP;
+	if (qopt->mqprio.preemptible_tcs &&
+	    !(adapter->flags & IGC_FLAG_TSN_REVERSE_TXQ_PRIO)) {
+		NL_SET_ERR_MSG_MOD(qopt->extack,
+				   "reverse-tsn-txq-prio private flag must be enabled before setting preemptible tc");
+		return -ENODEV;
+	}
 
 	igc_ptp_read(adapter, &now);
 
@@ -6583,6 +6594,8 @@ static int igc_save_qbv_schedule(struct igc_adapter *adapter,
 			ring->max_sdu = 0;
 	}
 
+	igc_fpe_save_preempt_queue(adapter, &qopt->mqprio);
+
 	return 0;
 }
 
@@ -6702,7 +6715,8 @@ static int igc_tc_query_caps(struct igc_adapter *adapter,
 	case TC_SETUP_QDISC_TAPRIO: {
 		struct tc_taprio_caps *caps = base->caps;
 
-		caps->broken_mqprio = true;
+		if (!(adapter->flags & IGC_FLAG_TSN_REVERSE_TXQ_PRIO))
+			caps->broken_mqprio = true;
 
 		if (hw->mac.type == igc_i225) {
 			caps->supports_queue_max_sdu = true;
@@ -6728,6 +6742,20 @@ static void igc_save_mqprio_params(struct igc_adapter *adapter, u8 num_tc,
 		adapter->queue_per_tc[i] = offset[i];
 }
 
+static bool
+igc_tsn_is_tc_to_queue_priority_ordered(struct tc_mqprio_qopt_offload *mqprio)
+{
+	int num_tc = mqprio->qopt.num_tc;
+	int i;
+
+	for (i = 1; i < num_tc; i++) {
+		if (mqprio->qopt.offset[i - 1] > mqprio->qopt.offset[i])
+			return false;
+	}
+
+	return true;
+}
+
 static int igc_tsn_enable_mqprio(struct igc_adapter *adapter,
 				 struct tc_mqprio_qopt_offload *mqprio)
 {
@@ -6739,6 +6767,7 @@ static int igc_tsn_enable_mqprio(struct igc_adapter *adapter,
 
 	if (!mqprio->qopt.num_tc) {
 		adapter->strict_priority_enable = false;
+		igc_fpe_clear_preempt_queue(adapter);
 		netdev_reset_tc(adapter->netdev);
 		goto apply;
 	}
@@ -6760,10 +6789,9 @@ static int igc_tsn_enable_mqprio(struct igc_adapter *adapter,
 		}
 	}
 
-	/* Preemption is not supported yet. */
-	if (mqprio->preemptible_tcs) {
+	if (!igc_tsn_is_tc_to_queue_priority_ordered(mqprio)) {
 		NL_SET_ERR_MSG_MOD(mqprio->extack,
-				   "Preemption is not supported yet");
+				   "tc to queue mapping must preserve increasing priority (higher tc -> higher queue)");
 		return -EOPNOTSUPP;
 	}
 
@@ -6786,6 +6814,7 @@ static int igc_tsn_enable_mqprio(struct igc_adapter *adapter,
 		adapter->queue_per_tc[i] = i;
 
 	mqprio->qopt.hw = TC_MQPRIO_HW_OFFLOAD_TCS;
+	igc_fpe_save_preempt_queue(adapter, mqprio);
 
 apply:
 	return igc_tsn_offload_apply(adapter);
diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.c b/drivers/net/ethernet/intel/igc/igc_tsn.c
index f22cc4d4f459..b23b9ca451a7 100644
--- a/drivers/net/ethernet/intel/igc/igc_tsn.c
+++ b/drivers/net/ethernet/intel/igc/igc_tsn.c
@@ -13,6 +13,13 @@
 #define TX_MAX_FRAG_SIZE	(TX_MIN_FRAG_SIZE * \
 				 (MAX_MULTPLIER_TX_MIN_FRAG + 1))
 
+enum tx_queue {
+	TX_QUEUE_0 = 0,
+	TX_QUEUE_1,
+	TX_QUEUE_2,
+	TX_QUEUE_3,
+};
+
 DEFINE_STATIC_KEY_FALSE(igc_fpe_enabled);
 
 static int igc_fpe_init_smd_frame(struct igc_ring *ring,
@@ -109,6 +116,18 @@ static int igc_fpe_xmit_smd_frame(struct igc_adapter *adapter,
 	return err;
 }
 
+static void igc_fpe_configure_tx(struct ethtool_mmsv *mmsv, bool tx_enable)
+{
+	struct igc_fpe_t *fpe = container_of(mmsv, struct igc_fpe_t, mmsv);
+	struct igc_adapter *adapter;
+
+	adapter = container_of(fpe, struct igc_adapter, fpe);
+	adapter->fpe.tx_enabled = tx_enable;
+
+	/* Update config since tx_enabled affects preemptible queue configuration */
+	igc_tsn_offload_apply(adapter);
+}
+
 static void igc_fpe_send_mpacket(struct ethtool_mmsv *mmsv,
 				 enum ethtool_mpacket type)
 {
@@ -130,15 +149,59 @@ static void igc_fpe_send_mpacket(struct ethtool_mmsv *mmsv,
 }
 
 static const struct ethtool_mmsv_ops igc_mmsv_ops = {
+	.configure_tx = igc_fpe_configure_tx,
 	.send_mpacket = igc_fpe_send_mpacket,
 };
 
 void igc_fpe_init(struct igc_adapter *adapter)
 {
 	adapter->fpe.tx_min_frag_size = TX_MIN_FRAG_SIZE;
+	adapter->fpe.tx_enabled = false;
 	ethtool_mmsv_init(&adapter->fpe.mmsv, adapter->netdev, &igc_mmsv_ops);
 }
 
+void igc_fpe_clear_preempt_queue(struct igc_adapter *adapter)
+{
+	for (int i = 0; i < adapter->num_tx_queues; i++) {
+		struct igc_ring *tx_ring = adapter->tx_ring[i];
+
+		tx_ring->preemptible = false;
+	}
+}
+
+static u32 igc_fpe_map_preempt_tc_to_queue(const struct igc_adapter *adapter,
+					   unsigned long preemptible_tcs)
+{
+	struct net_device *dev = adapter->netdev;
+	u32 i, queue = 0;
+
+	for (i = 0; i < dev->num_tc; i++) {
+		u32 offset, count;
+
+		if (!(preemptible_tcs & BIT(i)))
+			continue;
+
+		offset = dev->tc_to_txq[i].offset;
+		count = dev->tc_to_txq[i].count;
+		queue |= GENMASK(offset + count - 1, offset);
+	}
+
+	return queue;
+}
+
+void igc_fpe_save_preempt_queue(struct igc_adapter *adapter,
+				const struct tc_mqprio_qopt_offload *mqprio)
+{
+	u32 preemptible_queue = igc_fpe_map_preempt_tc_to_queue(adapter,
+								mqprio->preemptible_tcs);
+
+	for (int i = 0; i < adapter->num_tx_queues; i++) {
+		struct igc_ring *tx_ring = adapter->tx_ring[i];
+
+		tx_ring->preemptible = !!(preemptible_queue & BIT(i));
+	}
+}
+
 static bool is_any_launchtime(struct igc_adapter *adapter)
 {
 	int i;
@@ -238,7 +301,7 @@ bool igc_tsn_is_taprio_activated_by_user(struct igc_adapter *adapter)
 		adapter->taprio_offload_enable;
 }
 
-static void igc_tsn_tx_arb(struct igc_adapter *adapter, u16 *queue_per_tc)
+static void igc_tsn_tx_arb(struct igc_adapter *adapter, bool reverse_prio)
 {
 	struct igc_hw *hw = &adapter->hw;
 	u32 txarb;
@@ -250,10 +313,17 @@ static void igc_tsn_tx_arb(struct igc_adapter *adapter, u16 *queue_per_tc)
 		   IGC_TXARB_TXQ_PRIO_2_MASK |
 		   IGC_TXARB_TXQ_PRIO_3_MASK);
 
-	txarb |= IGC_TXARB_TXQ_PRIO_0(queue_per_tc[3]);
-	txarb |= IGC_TXARB_TXQ_PRIO_1(queue_per_tc[2]);
-	txarb |= IGC_TXARB_TXQ_PRIO_2(queue_per_tc[1]);
-	txarb |= IGC_TXARB_TXQ_PRIO_3(queue_per_tc[0]);
+	if (reverse_prio) {
+		txarb |= IGC_TXARB_TXQ_PRIO_0(TX_QUEUE_3);
+		txarb |= IGC_TXARB_TXQ_PRIO_1(TX_QUEUE_2);
+		txarb |= IGC_TXARB_TXQ_PRIO_2(TX_QUEUE_1);
+		txarb |= IGC_TXARB_TXQ_PRIO_3(TX_QUEUE_0);
+	} else {
+		txarb |= IGC_TXARB_TXQ_PRIO_0(TX_QUEUE_0);
+		txarb |= IGC_TXARB_TXQ_PRIO_1(TX_QUEUE_1);
+		txarb |= IGC_TXARB_TXQ_PRIO_2(TX_QUEUE_2);
+		txarb |= IGC_TXARB_TXQ_PRIO_3(TX_QUEUE_3);
+	}
 
 	wr32(IGC_TXARB, txarb);
 }
@@ -286,7 +356,6 @@ static void igc_tsn_set_rxpbsize(struct igc_adapter *adapter,
  */
 static int igc_tsn_disable_offload(struct igc_adapter *adapter)
 {
-	u16 queue_per_tc[4] = { 3, 2, 1, 0 };
 	struct igc_hw *hw = &adapter->hw;
 	u32 tqavctrl;
 	int i;
@@ -308,9 +377,16 @@ static int igc_tsn_disable_offload(struct igc_adapter *adapter)
 	wr32(IGC_TQAVCTRL, tqavctrl);
 
 	for (i = 0; i < adapter->num_tx_queues; i++) {
+		int reg_idx = adapter->tx_ring[i]->reg_idx;
+		u32 txdctl;
+
 		wr32(IGC_TXQCTL(i), 0);
 		wr32(IGC_STQT(i), 0);
 		wr32(IGC_ENDQT(i), NSEC_PER_SEC);
+
+		txdctl = rd32(IGC_TXDCTL(reg_idx));
+		txdctl &= ~IGC_TXDCTL_PRIORITY_HIGH;
+		wr32(IGC_TXDCTL(reg_idx), txdctl);
 	}
 
 	wr32(IGC_QBVCYCLET_S, 0);
@@ -319,7 +395,7 @@ static int igc_tsn_disable_offload(struct igc_adapter *adapter)
 	/* Restore the default Tx arbitration: Priority 0 has the highest
 	 * priority and is assigned to queue 0 and so on and so forth.
 	 */
-	igc_tsn_tx_arb(adapter, queue_per_tc);
+	igc_tsn_tx_arb(adapter, false);
 
 	adapter->flags &= ~IGC_FLAG_TSN_QBV_ENABLED;
 
@@ -385,15 +461,13 @@ static int igc_tsn_enable_offload(struct igc_adapter *adapter)
 	if (igc_is_device_id_i226(hw))
 		igc_tsn_set_retx_qbvfullthreshold(adapter);
 
-	if (adapter->strict_priority_enable) {
-		/* Configure queue priorities according to the user provided
-		 * mapping.
-		 */
-		igc_tsn_tx_arb(adapter, adapter->queue_per_tc);
-	}
+	if (adapter->strict_priority_enable ||
+	    adapter->flags & IGC_FLAG_TSN_REVERSE_TXQ_PRIO)
+		igc_tsn_tx_arb(adapter, true);
 
 	for (i = 0; i < adapter->num_tx_queues; i++) {
 		struct igc_ring *ring = adapter->tx_ring[i];
+		u32 txdctl = rd32(IGC_TXDCTL(ring->reg_idx));
 		u32 txqctl = 0;
 		u16 cbs_value;
 		u32 tqavcc;
@@ -427,6 +501,22 @@ static int igc_tsn_enable_offload(struct igc_adapter *adapter)
 		if (ring->launchtime_enable)
 			txqctl |= IGC_TXQCTL_QUEUE_MODE_LAUNCHT;
 
+		if (!adapter->fpe.tx_enabled) {
+			/* fpe inactive: clear both flags */
+			txqctl &= ~IGC_TXQCTL_PREEMPTIBLE;
+			txdctl &= ~IGC_TXDCTL_PRIORITY_HIGH;
+		} else if (ring->preemptible) {
+			/* fpe active + preemptible: enable preemptible queue + set low priority */
+			txqctl |= IGC_TXQCTL_PREEMPTIBLE;
+			txdctl &= ~IGC_TXDCTL_PRIORITY_HIGH;
+		} else {
+			/* fpe active + express: enable express queue + set high priority */
+			txqctl &= ~IGC_TXQCTL_PREEMPTIBLE;
+			txdctl |= IGC_TXDCTL_PRIORITY_HIGH;
+		}
+
+		wr32(IGC_TXDCTL(ring->reg_idx), txdctl);
+
 		/* Skip configuring CBS for Q2 and Q3 */
 		if (i > 1)
 			goto skip_cbs;
diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.h b/drivers/net/ethernet/intel/igc/igc_tsn.h
index c2a77229207b..a95b893459d7 100644
--- a/drivers/net/ethernet/intel/igc/igc_tsn.h
+++ b/drivers/net/ethernet/intel/igc/igc_tsn.h
@@ -4,6 +4,8 @@
 #ifndef _IGC_TSN_H_
 #define _IGC_TSN_H_
 
+#include <net/pkt_sched.h>
+
 #define IGC_RX_MIN_FRAG_SIZE		60
 #define SMD_FRAME_SIZE			60
 
@@ -15,6 +17,9 @@ enum igc_txd_popts_type {
 DECLARE_STATIC_KEY_FALSE(igc_fpe_enabled);
 
 void igc_fpe_init(struct igc_adapter *adapter);
+void igc_fpe_clear_preempt_queue(struct igc_adapter *adapter);
+void igc_fpe_save_preempt_queue(struct igc_adapter *adapter,
+				const struct tc_mqprio_qopt_offload *mqprio);
 u32 igc_fpe_get_supported_frag_size(u32 frag_size);
 int igc_tsn_offload_apply(struct igc_adapter *adapter);
 int igc_tsn_reset(struct igc_adapter *adapter);