tg3: Determine PCI function number in one place

tg3 devices will need to know exactly what function number they are so
that they can communicate their status to the other functions.  In a KVM
environment, the function number of a device presented by the kernel
might not be the true function number, so an alternative method to
determine the function number is needed.

This patch used to contain an implementation for the alternative method,
but recently we discovered a hardware bug that renders it incorrect.
While new method is not yet known, it is still useful to consolidate the
code that determines the PCI function to one location and use the
results throughout the code.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index 5d4283e..6f1f36c 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -1170,7 +1170,7 @@
 	if (tg3_flag(tp, 5717_PLUS)) {
 		u32 is_serdes;
 
-		tp->phy_addr = PCI_FUNC(tp->pdev->devfn) + 1;
+		tp->phy_addr = tp->pci_fn + 1;
 
 		if (tp->pci_chip_rev_id != CHIPREV_ID_5717_A0)
 			is_serdes = tr32(SG_DIG_STATUS) & SG_DIG_IS_SERDES;
@@ -13951,6 +13951,14 @@
 	val = tr32(MEMARB_MODE);
 	tw32(MEMARB_MODE, val | MEMARB_MODE_ENABLE);
 
+	if (tg3_flag(tp, PCIX_MODE)) {
+		pci_read_config_dword(tp->pdev,
+				      tp->pcix_cap + PCI_X_STATUS, &val);
+		tp->pci_fn = val & 0x7;
+	} else {
+		tp->pci_fn = PCI_FUNC(tp->pdev->devfn) & 3;
+	}
+
 	/* Get eeprom hw config before calling tg3_set_power_state().
 	 * In particular, the TG3_FLAG_IS_NIC flag must be
 	 * determined before calling tg3_set_power_state() so that
@@ -14316,9 +14324,9 @@
 		else
 			tg3_nvram_unlock(tp);
 	} else if (tg3_flag(tp, 5717_PLUS)) {
-		if (PCI_FUNC(tp->pdev->devfn) & 1)
+		if (tp->pci_fn & 1)
 			mac_offset = 0xcc;
-		if (PCI_FUNC(tp->pdev->devfn) > 1)
+		if (tp->pci_fn > 1)
 			mac_offset += 0x18c;
 	} else if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5906)
 		mac_offset = 0x10;