net: ngbe: specify IRQ vector when the number of VFs is 7

For NGBE devices, the queue number is limited to be 1 when SRIOV is
enabled. In this case, IRQ vector[0] is used for MISC and vector[1] is
used for queue, based on the previous patches. But for the hardware
design, the IRQ vector[1] must be allocated for use by the VF[6] when
the number of VFs is 7. So the IRQ vector[0] should be shared for PF
MISC and QUEUE interrupts.

+-----------+----------------------+
| Vector    | Assigned To          |
+-----------+----------------------+
| Vector 0  | PF MISC and QUEUE    |
| Vector 1  | VF 6                 |
| Vector 2  | VF 5                 |
| Vector 3  | VF 4                 |
| Vector 4  | VF 3                 |
| Vector 5  | VF 2                 |
| Vector 6  | VF 1                 |
| Vector 7  | VF 0                 |
+-----------+----------------------+

Minimize code modifications, only adjust the IRQ vector number for this
case.

Fixes: 877253d2cb ("net: ngbe: add sriov function support")
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Link: https://patch.msgid.link/20250701063030.59340-4-jiawenwu@trustnetic.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/wangxun/libwx/wx_lib.c

@@ -1795,6 +1795,13 @@ static int wx_acquire_msix_vectors(struct wx *wx)
 	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;
 }
 
@@ -2293,6 +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);

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)

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,

drivers/net/ethernet/wangxun/ngbe/ngbe_main.c

@@ -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

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(A)			BIT((A)->num_q_vectors)
+#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