Merge branch 'fix-irq-vectors'

Jiawen Wu says:

====================
Fix IRQ vectors

The interrupt vector order was adjusted by [1]commit 937d46ecc5f9 ("net:
wangxun: add ethtool_ops for channel number") in Linux-6.8. Because at
that time, the MISC interrupt acts as the parent interrupt in the GPIO
IRQ chip. When the number of Rx/Tx ring changes, the last MISC
interrupt must be reallocated. Then the GPIO interrupt controller would
be corrupted. So the initial plan was to adjust the sequence of the
interrupt vectors, let MISC interrupt to be the first one and do not
free it.

Later, irq_domain was introduced in [2]commit aefd013624a1 ("net: txgbe:
use irq_domain for interrupt controller") to avoid this problem.
However, the vector sequence adjustment was not reverted. So there is
still one problem that has been left unresolved.

Due to hardware limitations of NGBE, queue IRQs can only be requested
on vector 0 to 7. When the number of queues is set to the maximum 8,
the PCI IRQ vectors are allocated from 0 to 8. The vector 0 is used by
MISC interrupt, and althrough the vector 8 is used by queue interrupt,
it is unable to receive packets. This will cause some packets to be
dropped when RSS is enabled and they are assigned to queue 8.

This patch set fix the above problems.

[1] https://git.kernel.org/netdev/net-next/c/937d46ecc5f9
[2] https://git.kernel.org/netdev/net-next/c/aefd013624a1
====================

Link: https://patch.msgid.link/20250701063030.59340-1-jiawenwu@trustnetic.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

8 files changed, 42 insertions, 31 deletions

diff --git a/drivers/net/ethernet/wangxun/libwx/wx_lib.c b/drivers/net/ethernet/wangxun/libwx/wx_lib.c
index 59840ba9c1fe..55e252789db3 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_lib.c
+++ b/drivers/net/ethernet/wangxun/libwx/wx_lib.c
@@ -1747,7 +1747,7 @@ static void wx_set_num_queues(struct wx *wx)
  */
 static int wx_acquire_msix_vectors(struct wx *wx)
 {
-	struct irq_affinity affd = { .pre_vectors = 1 };
+	struct irq_affinity affd = { .post_vectors = 1 };
 	int nvecs, i;
 
 	/* We start by asking for one vector per queue pair */
@@ -1784,16 +1784,24 @@ static int wx_acquire_msix_vectors(struct wx *wx)
 		return nvecs;
 	}
 
-	wx->msix_entry->entry = 0;
-	wx->msix_entry->vector = pci_irq_vector(wx->pdev, 0);
 	nvecs -= 1;
 	for (i = 0; i < nvecs; i++) {
 		wx->msix_q_entries[i].entry = i;
-		wx->msix_q_entries[i].vector = pci_irq_vector(wx->pdev, i + 1);
+		wx->msix_q_entries[i].vector = pci_irq_vector(wx->pdev, i);
 	}
 
 	wx->num_q_vectors = nvecs;
 
+	wx->msix_entry->entry = nvecs;
+	wx->msix_entry->vector = pci_irq_vector(wx->pdev, nvecs);
+
+	if (test_bit(WX_FLAG_IRQ_VECTOR_SHARED, wx->flags)) {
+		wx->msix_entry->entry = 0;
+		wx->msix_entry->vector = pci_irq_vector(wx->pdev, 0);
+		wx->msix_q_entries[0].entry = 0;
+		wx->msix_q_entries[0].vector = pci_irq_vector(wx->pdev, 1);
+	}
+
 	return 0;
 }
 
@@ -2292,6 +2300,8 @@ static void wx_set_ivar(struct wx *wx, s8 direction,
 
 	if (direction == -1) {
 		/* other causes */
+		if (test_bit(WX_FLAG_IRQ_VECTOR_SHARED, wx->flags))
+			msix_vector = 0;
 		msix_vector |= WX_PX_IVAR_ALLOC_VAL;
 		index = 0;
 		ivar = rd32(wx, WX_PX_MISC_IVAR);
@@ -2300,8 +2310,6 @@ static void wx_set_ivar(struct wx *wx, s8 direction,
 		wr32(wx, WX_PX_MISC_IVAR, ivar);
 	} else {
 		/* tx or rx causes */
-		if (!(wx->mac.type == wx_mac_em && wx->num_vfs == 7))
-			msix_vector += 1; /* offset for queue vectors */
 		msix_vector |= WX_PX_IVAR_ALLOC_VAL;
 		index = ((16 * (queue & 1)) + (8 * direction));
 		ivar = rd32(wx, WX_PX_IVAR(queue >> 1));
@@ -2340,7 +2348,7 @@ void wx_write_eitr(struct wx_q_vector *q_vector)
 
 	itr_reg |= WX_PX_ITR_CNT_WDIS;
 
-	wr32(wx, WX_PX_ITR(v_idx + 1), itr_reg);
+	wr32(wx, WX_PX_ITR(v_idx), itr_reg);
 }
 
 /**
@@ -2393,9 +2401,9 @@ void wx_configure_vectors(struct wx *wx)
 		wx_write_eitr(q_vector);
 	}
 
-	wx_set_ivar(wx, -1, 0, 0);
+	wx_set_ivar(wx, -1, 0, v_idx);
 	if (pdev->msix_enabled)
-		wr32(wx, WX_PX_ITR(0), 1950);
+		wr32(wx, WX_PX_ITR(v_idx), 1950);
 }
 EXPORT_SYMBOL(wx_configure_vectors);
 
diff --git a/drivers/net/ethernet/wangxun/libwx/wx_sriov.c b/drivers/net/ethernet/wangxun/libwx/wx_sriov.c
index e8656d9d733b..c82ae137756c 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_sriov.c
+++ b/drivers/net/ethernet/wangxun/libwx/wx_sriov.c
@@ -64,6 +64,7 @@ static void wx_sriov_clear_data(struct wx *wx)
 	wr32m(wx, WX_PSR_VM_CTL, WX_PSR_VM_CTL_POOL_MASK, 0);
 	wx->ring_feature[RING_F_VMDQ].offset = 0;
 
+	clear_bit(WX_FLAG_IRQ_VECTOR_SHARED, wx->flags);
 	clear_bit(WX_FLAG_SRIOV_ENABLED, wx->flags);
 	/* Disable VMDq flag so device will be set in NM mode */
 	if (wx->ring_feature[RING_F_VMDQ].limit == 1)
@@ -78,6 +79,9 @@ static int __wx_enable_sriov(struct wx *wx, u8 num_vfs)
 	set_bit(WX_FLAG_SRIOV_ENABLED, wx->flags);
 	dev_info(&wx->pdev->dev, "SR-IOV enabled with %d VFs\n", num_vfs);
 
+	if (num_vfs == 7 && wx->mac.type == wx_mac_em)
+		set_bit(WX_FLAG_IRQ_VECTOR_SHARED, wx->flags);
+
 	/* Enable VMDq flag so device will be set in VM mode */
 	set_bit(WX_FLAG_VMDQ_ENABLED, wx->flags);
 	if (!wx->ring_feature[RING_F_VMDQ].limit)
diff --git a/drivers/net/ethernet/wangxun/libwx/wx_type.h b/drivers/net/ethernet/wangxun/libwx/wx_type.h
index 7730c9fc3e02..c363379126c0 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_type.h
+++ b/drivers/net/ethernet/wangxun/libwx/wx_type.h
@@ -1191,6 +1191,7 @@ enum wx_pf_flags {
 	WX_FLAG_VMDQ_ENABLED,
 	WX_FLAG_VLAN_PROMISC,
 	WX_FLAG_SRIOV_ENABLED,
+	WX_FLAG_IRQ_VECTOR_SHARED,
 	WX_FLAG_FDIR_CAPABLE,
 	WX_FLAG_FDIR_HASH,
 	WX_FLAG_FDIR_PERFECT,
@@ -1343,7 +1344,7 @@ struct wx {
 };
 
 #define WX_INTR_ALL (~0ULL)
-#define WX_INTR_Q(i) BIT((i) + 1)
+#define WX_INTR_Q(i) BIT((i))
 
 /* register operations */
 #define wr32(a, reg, value)	writel((value), ((a)->hw_addr + (reg)))
diff --git a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
index b5022c49dc5e..e0fc897b0a58 100644
--- a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
+++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
@@ -161,7 +161,7 @@ static void ngbe_irq_enable(struct wx *wx, bool queues)
 	if (queues)
 		wx_intr_enable(wx, NGBE_INTR_ALL);
 	else
-		wx_intr_enable(wx, NGBE_INTR_MISC);
+		wx_intr_enable(wx, NGBE_INTR_MISC(wx));
 }
 
 /**
@@ -286,7 +286,7 @@ static int ngbe_request_msix_irqs(struct wx *wx)
 	 * for queue. But when num_vfs == 7, vector[1] is assigned to vf6.
 	 * Misc and queue should reuse interrupt vector[0].
 	 */
-	if (wx->num_vfs == 7)
+	if (test_bit(WX_FLAG_IRQ_VECTOR_SHARED, wx->flags))
 		err = request_irq(wx->msix_entry->vector,
 				  ngbe_misc_and_queue, 0, netdev->name, wx);
 	else
diff --git a/drivers/net/ethernet/wangxun/ngbe/ngbe_type.h b/drivers/net/ethernet/wangxun/ngbe/ngbe_type.h
index bb74263f0498..3b2ca7f47e33 100644
--- a/drivers/net/ethernet/wangxun/ngbe/ngbe_type.h
+++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_type.h
@@ -87,7 +87,7 @@
 #define NGBE_PX_MISC_IC_TIMESYNC		BIT(11) /* time sync */
 
 #define NGBE_INTR_ALL				0x1FF
-#define NGBE_INTR_MISC				BIT(0)
+#define NGBE_INTR_MISC(A)			BIT((A)->msix_entry->entry)
 
 #define NGBE_PHY_CONFIG(reg_offset)		(0x14000 + ((reg_offset) * 4))
 #define NGBE_CFG_LAN_SPEED			0x14440
diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_irq.c b/drivers/net/ethernet/wangxun/txgbe/txgbe_irq.c
index 20b9a28bcb55..3885283681ec 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_irq.c
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_irq.c
@@ -31,7 +31,7 @@ void txgbe_irq_enable(struct wx *wx, bool queues)
 	wr32(wx, WX_PX_MISC_IEN, misc_ien);
 
 	/* unmask interrupt */
-	wx_intr_enable(wx, TXGBE_INTR_MISC);
+	wx_intr_enable(wx, TXGBE_INTR_MISC(wx));
 	if (queues)
 		wx_intr_enable(wx, TXGBE_INTR_QALL(wx));
 }
@@ -78,7 +78,6 @@ free_queue_irqs:
 		free_irq(wx->msix_q_entries[vector].vector,
 			 wx->q_vector[vector]);
 	}
-	wx_reset_interrupt_capability(wx);
 	return err;
 }
 
@@ -132,7 +131,7 @@ static irqreturn_t txgbe_misc_irq_handle(int irq, void *data)
 		txgbe->eicr = eicr;
 		if (eicr & TXGBE_PX_MISC_IC_VF_MBOX) {
 			wx_msg_task(txgbe->wx);
-			wx_intr_enable(wx, TXGBE_INTR_MISC);
+			wx_intr_enable(wx, TXGBE_INTR_MISC(wx));
 		}
 		return IRQ_WAKE_THREAD;
 	}
@@ -184,7 +183,7 @@ static irqreturn_t txgbe_misc_irq_thread_fn(int irq, void *data)
 		nhandled++;
 	}
 
-	wx_intr_enable(wx, TXGBE_INTR_MISC);
+	wx_intr_enable(wx, TXGBE_INTR_MISC(wx));
 	return (nhandled > 0 ? IRQ_HANDLED : IRQ_NONE);
 }
 
@@ -211,6 +210,7 @@ void txgbe_free_misc_irq(struct txgbe *txgbe)
 	free_irq(txgbe->link_irq, txgbe);
 	free_irq(txgbe->misc.irq, txgbe);
 	txgbe_del_irq_domain(txgbe);
+	txgbe->wx->misc_irq_domain = false;
 }
 
 int txgbe_setup_misc_irq(struct txgbe *txgbe)
diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
index f3d2778b8e35..a5867f3c93fc 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
@@ -458,10 +458,14 @@ static int txgbe_open(struct net_device *netdev)
 
 	wx_configure(wx);
 
-	err = txgbe_request_queue_irqs(wx);
+	err = txgbe_setup_misc_irq(wx->priv);
 	if (err)
 		goto err_free_resources;
 
+	err = txgbe_request_queue_irqs(wx);
+	if (err)
+		goto err_free_misc_irq;
+
 	/* Notify the stack of the actual queue counts. */
 	err = netif_set_real_num_tx_queues(netdev, wx->num_tx_queues);
 	if (err)
@@ -479,6 +483,9 @@ static int txgbe_open(struct net_device *netdev)
 
 err_free_irq:
 	wx_free_irq(wx);
+err_free_misc_irq:
+	txgbe_free_misc_irq(wx->priv);
+	wx_reset_interrupt_capability(wx);
 err_free_resources:
 	wx_free_resources(wx);
 err_reset:
@@ -519,6 +526,7 @@ static int txgbe_close(struct net_device *netdev)
 	wx_ptp_stop(wx);
 	txgbe_down(wx);
 	wx_free_irq(wx);
+	txgbe_free_misc_irq(wx->priv);
 	wx_free_resources(wx);
 	txgbe_fdir_filter_exit(wx);
 	wx_control_hw(wx, false);
@@ -564,7 +572,6 @@ static void txgbe_shutdown(struct pci_dev *pdev)
 int txgbe_setup_tc(struct net_device *dev, u8 tc)
 {
 	struct wx *wx = netdev_priv(dev);
-	struct txgbe *txgbe = wx->priv;
 
 	/* Hardware has to reinitialize queues and interrupts to
 	 * match packet buffer alignment. Unfortunately, the
@@ -575,7 +582,6 @@ int txgbe_setup_tc(struct net_device *dev, u8 tc)
 	else
 		txgbe_reset(wx);
 
-	txgbe_free_misc_irq(txgbe);
 	wx_clear_interrupt_scheme(wx);
 
 	if (tc)
@@ -584,7 +590,6 @@ int txgbe_setup_tc(struct net_device *dev, u8 tc)
 		netdev_reset_tc(dev);
 
 	wx_init_interrupt_scheme(wx);
-	txgbe_setup_misc_irq(txgbe);
 
 	if (netif_running(dev))
 		txgbe_open(dev);
@@ -882,13 +887,9 @@ static int txgbe_probe(struct pci_dev *pdev,
 
 	txgbe_init_fdir(txgbe);
 
-	err = txgbe_setup_misc_irq(txgbe);
-	if (err)
-		goto err_release_hw;
-
 	err = txgbe_init_phy(txgbe);
 	if (err)
-		goto err_free_misc_irq;
+		goto err_release_hw;
 
 	err = register_netdev(netdev);
 	if (err)
@@ -916,8 +917,6 @@ static int txgbe_probe(struct pci_dev *pdev,
 
 err_remove_phy:
 	txgbe_remove_phy(txgbe);
-err_free_misc_irq:
-	txgbe_free_misc_irq(txgbe);
 err_release_hw:
 	wx_clear_interrupt_scheme(wx);
 	wx_control_hw(wx, false);
@@ -957,7 +956,6 @@ static void txgbe_remove(struct pci_dev *pdev)
 	unregister_netdev(netdev);
 
 	txgbe_remove_phy(txgbe);
-	txgbe_free_misc_irq(txgbe);
 	wx_free_isb_resources(wx);
 
 	pci_release_selected_regions(pdev,
diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_type.h b/drivers/net/ethernet/wangxun/txgbe/txgbe_type.h
index 42ec815159e8..41915d7dd372 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_type.h
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_type.h
@@ -302,8 +302,8 @@ struct txgbe_fdir_filter {
 #define TXGBE_DEFAULT_RX_WORK           128
 #endif
 
-#define TXGBE_INTR_MISC       BIT(0)
-#define TXGBE_INTR_QALL(A)    GENMASK((A)->num_q_vectors, 1)
+#define TXGBE_INTR_MISC(A)    BIT((A)->num_q_vectors)
+#define TXGBE_INTR_QALL(A)    (TXGBE_INTR_MISC(A) - 1)
 
 #define TXGBE_MAX_EITR        GENMASK(11, 3)