ixgbe: correct function number for some 82598 parts

Some 82598 parts have LAN0 disabled and LAN1 enabled and the LAN ID bits in
Device Status register report the NIC as having only LAN1 as enabled. This
causes ixgbe_set_lan_id_multi_port_pcie() to set bus->func = 1 which is
incorrect.

Force bus->func to 0 when LAN0 is disabled in the EEPROM.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NEvan Swanson <evan.swanson@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ixgbe/ixgbe_82598.c

@@ -1188,6 +1188,38 @@ static u32 ixgbe_get_supported_physical_layer_82598(struct ixgbe_hw *hw)
 	return physical_layer;
 }
 
+/**
+ *  ixgbe_set_lan_id_multi_port_pcie_82598 - Set LAN id for PCIe multiple
+ *  port devices.
+ *  @hw: pointer to the HW structure
+ *
+ *  Calls common function and corrects issue with some single port devices
+ *  that enable LAN1 but not LAN0.
+ **/
+static void ixgbe_set_lan_id_multi_port_pcie_82598(struct ixgbe_hw *hw)
+{
+	struct ixgbe_bus_info *bus = &hw->bus;
+	u16 pci_gen = 0;
+	u16 pci_ctrl2 = 0;
+
+	ixgbe_set_lan_id_multi_port_pcie(hw);
+
+	/* check if LAN0 is disabled */
+	hw->eeprom.ops.read(hw, IXGBE_PCIE_GENERAL_PTR, &pci_gen);
+	if ((pci_gen != 0) && (pci_gen != 0xFFFF)) {
+
+		hw->eeprom.ops.read(hw, pci_gen + IXGBE_PCIE_CTRL2, &pci_ctrl2);
+
+		/* if LAN0 is completely disabled force function to 0 */
+		if ((pci_ctrl2 & IXGBE_PCIE_CTRL2_LAN_DISABLE) &&
+		    !(pci_ctrl2 & IXGBE_PCIE_CTRL2_DISABLE_SELECT) &&
+		    !(pci_ctrl2 & IXGBE_PCIE_CTRL2_DUMMY_ENABLE)) {
+
+			bus->func = 0;
+		}
+	}
+}
+
 static struct ixgbe_mac_operations mac_ops_82598 = {
 	.init_hw		= &ixgbe_init_hw_generic,
 	.reset_hw		= &ixgbe_reset_hw_82598,
@@ -1199,7 +1231,7 @@ static struct ixgbe_mac_operations mac_ops_82598 = {
 	.get_mac_addr		= &ixgbe_get_mac_addr_generic,
 	.stop_adapter		= &ixgbe_stop_adapter_generic,
 	.get_bus_info           = &ixgbe_get_bus_info_generic,
-	.set_lan_id             = &ixgbe_set_lan_id_multi_port_pcie,
+	.set_lan_id             = &ixgbe_set_lan_id_multi_port_pcie_82598,
 	.read_analog_reg8	= &ixgbe_read_analog_reg8_82598,
 	.write_analog_reg8	= &ixgbe_write_analog_reg8_82598,
 	.setup_link		= &ixgbe_setup_mac_link_82598,

drivers/net/ixgbe/ixgbe_type.h

@@ -1616,6 +1616,11 @@
 #define IXGBE_FLUDONE_ATTEMPTS 20000
 #endif
 
+#define IXGBE_PCIE_CTRL2                 0x5   /* PCIe Control 2 Offset */
+#define IXGBE_PCIE_CTRL2_DUMMY_ENABLE    0x8   /* Dummy Function Enable */
+#define IXGBE_PCIE_CTRL2_LAN_DISABLE     0x2   /* LAN PCI Disable */
+#define IXGBE_PCIE_CTRL2_DISABLE_SELECT  0x1   /* LAN Disable Select */
+
 #define IXGBE_SAN_MAC_ADDR_PORT0_OFFSET  0x0
 #define IXGBE_SAN_MAC_ADDR_PORT1_OFFSET  0x3
 #define IXGBE_DEVICE_CAPS_ALLOW_ANY_SFP  0x1