r8169: fix RxMissed register access

- the register is defined for the 8169 chipset only and there is
  no 8169 beyond RTL_GIGA_MAC_VER_06.
- only the lower 3 bytes of the register are valid

Fixes:
1. http://bugzilla.kernel.org/show_bug.cgi?id=10180
2. http://bugzilla.kernel.org/show_bug.cgi?id=11062 (bits of)

Tested by Hermann Gausterer and Adam Huffman.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Edward Hsu <edward_hsu@realtek.com.tw>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
index 1822491..f28c202 100644
--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -2286,8 +2286,6 @@
 
 	RTL_R8(IntrMask);
 
-	RTL_W32(RxMissed, 0);
-
 	rtl_set_rx_mode(dev);
 
 	RTL_W8(ChipCmd, CmdTxEnb | CmdRxEnb);
@@ -2412,8 +2410,6 @@
 
 	RTL_R8(IntrMask);
 
-	RTL_W32(RxMissed, 0);
-
 	rtl_set_rx_mode(dev);
 
 	RTL_W8(ChipCmd, CmdTxEnb | CmdRxEnb);
@@ -3191,6 +3187,17 @@
 	return work_done;
 }
 
+static void rtl8169_rx_missed(struct net_device *dev, void __iomem *ioaddr)
+{
+	struct rtl8169_private *tp = netdev_priv(dev);
+
+	if (tp->mac_version > RTL_GIGA_MAC_VER_06)
+		return;
+
+	dev->stats.rx_missed_errors += (RTL_R32(RxMissed) & 0xffffff);
+	RTL_W32(RxMissed, 0);
+}
+
 static void rtl8169_down(struct net_device *dev)
 {
 	struct rtl8169_private *tp = netdev_priv(dev);
@@ -3208,9 +3215,7 @@
 
 	rtl8169_asic_down(ioaddr);
 
-	/* Update the error counts. */
-	dev->stats.rx_missed_errors += RTL_R32(RxMissed);
-	RTL_W32(RxMissed, 0);
+	rtl8169_rx_missed(dev, ioaddr);
 
 	spin_unlock_irq(&tp->lock);
 
@@ -3332,8 +3337,7 @@
 
 	if (netif_running(dev)) {
 		spin_lock_irqsave(&tp->lock, flags);
-		dev->stats.rx_missed_errors += RTL_R32(RxMissed);
-		RTL_W32(RxMissed, 0);
+		rtl8169_rx_missed(dev, ioaddr);
 		spin_unlock_irqrestore(&tp->lock, flags);
 	}
 
@@ -3358,8 +3362,7 @@
 
 	rtl8169_asic_down(ioaddr);
 
-	dev->stats.rx_missed_errors += RTL_R32(RxMissed);
-	RTL_W32(RxMissed, 0);
+	rtl8169_rx_missed(dev, ioaddr);
 
 	spin_unlock_irq(&tp->lock);