r8169: improve rtl8169_get_mac_version

Currently code snippet (RTL_R32(tp, TxConfig) >> 20) & 0xfcf is used
in few places to extract the chip XID. Change the code to do the XID
extraction only once.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/realtek/r8169_main.c

@@ -2045,7 +2045,7 @@ static void rtl_enable_eee(struct rtl8169_private *tp)
 		phy_write_mmd(phydev, MDIO_MMD_AN, MDIO_AN_EEE_ADV, adv);
 }
 
-static void rtl8169_get_mac_version(struct rtl8169_private *tp)
+static enum mac_version rtl8169_get_mac_version(u16 xid, bool gmii)
 {
 	/*
 	 * The driver currently handles the 8168Bf and the 8168Be identically
@@ -2061,7 +2061,7 @@ static void rtl8169_get_mac_version(struct rtl8169_private *tp)
 	static const struct rtl_mac_info {
 		u16 mask;
 		u16 val;
-		u16 mac_version;
+		enum mac_version ver;
 	} mac_info[] = {
 		/* 8125 family. */
 		{ 0x7cf, 0x608,	RTL_GIGA_MAC_VER_60 },
@@ -2148,22 +2148,22 @@ static void rtl8169_get_mac_version(struct rtl8169_private *tp)
 		{ 0x000, 0x000,	RTL_GIGA_MAC_NONE   }
 	};
 	const struct rtl_mac_info *p = mac_info;
-	u16 reg = RTL_R32(tp, TxConfig) >> 20;
+	enum mac_version ver;
 
-	while ((reg & p->mask) != p->val)
+	while ((xid & p->mask) != p->val)
 		p++;
-	tp->mac_version = p->mac_version;
-
-	if (tp->mac_version == RTL_GIGA_MAC_NONE) {
-		dev_err(tp_to_dev(tp), "unknown chip XID %03x\n", reg & 0xfcf);
-	} else if (!tp->supports_gmii) {
-		if (tp->mac_version == RTL_GIGA_MAC_VER_42)
-			tp->mac_version = RTL_GIGA_MAC_VER_43;
-		else if (tp->mac_version == RTL_GIGA_MAC_VER_45)
-			tp->mac_version = RTL_GIGA_MAC_VER_47;
-		else if (tp->mac_version == RTL_GIGA_MAC_VER_46)
-			tp->mac_version = RTL_GIGA_MAC_VER_48;
+	ver = p->ver;
+
+	if (ver != RTL_GIGA_MAC_NONE && !gmii) {
+		if (ver == RTL_GIGA_MAC_VER_42)
+			ver = RTL_GIGA_MAC_VER_43;
+		else if (ver == RTL_GIGA_MAC_VER_45)
+			ver = RTL_GIGA_MAC_VER_47;
+		else if (ver == RTL_GIGA_MAC_VER_46)
+			ver = RTL_GIGA_MAC_VER_48;
 	}
+
+	return ver;
 }
 
 static void rtl_release_firmware(struct rtl8169_private *tp)
@@ -5440,9 +5440,10 @@ static void rtl_init_mac_address(struct rtl8169_private *tp)
 static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	struct rtl8169_private *tp;
+	int jumbo_max, region, rc;
+	enum mac_version chipset;
 	struct net_device *dev;
-	int chipset, region;
-	int jumbo_max, rc;
+	u16 xid;
 
 	/* Some tools for creating an initramfs don't consider softdeps, then
 	 * r8169.ko may be in initramfs, but realtek.ko not. Then the generic
@@ -5509,10 +5510,16 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	tp->mmio_addr = pcim_iomap_table(pdev)[region];
 
+	xid = (RTL_R32(tp, TxConfig) >> 20) & 0xfcf;
+
 	/* Identify chip attached to board */
-	rtl8169_get_mac_version(tp);
-	if (tp->mac_version == RTL_GIGA_MAC_NONE)
+	chipset = rtl8169_get_mac_version(xid, tp->supports_gmii);
+	if (chipset == RTL_GIGA_MAC_NONE) {
+		dev_err(&pdev->dev, "unknown chip XID %03x\n", xid);
 		return -ENODEV;
+	}
+
+	tp->mac_version = chipset;
 
 	tp->cp_cmd = RTL_R16(tp, CPlusCmd);
 
@@ -5530,8 +5537,6 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	pci_set_master(pdev);
 
-	chipset = tp->mac_version;
-
 	rc = rtl_alloc_irq(tp);
 	if (rc < 0) {
 		dev_err(&pdev->dev, "Can't allocate interrupt\n");
@@ -5619,8 +5624,7 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto err_mdio_unregister;
 
 	netif_info(tp, probe, dev, "%s, %pM, XID %03x, IRQ %d\n",
-		   rtl_chip_infos[chipset].name, dev->dev_addr,
-		   (RTL_R32(tp, TxConfig) >> 20) & 0xfcf,
+		   rtl_chip_infos[chipset].name, dev->dev_addr, xid,
 		   pci_irq_vector(pdev, 0));
 
 	if (jumbo_max)