igb: only read phy specific stats if in internal phy mode

There are a couple statistics registers that are not meant to
be read when in SGMII/serdes mode. This patch adds a check to
verify mode before reading and updating these statistics.

Signed-off-by: Nicholas Nunley <nicholasx.d.nunley@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 3 deletions

diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index b989b34a4adb..cba0115a6a57 100644
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -3975,7 +3975,7 @@ void igb_update_stats(struct igb_adapter *adapter)
         struct net_device_stats *net_stats = igb_get_stats(adapter->netdev);
         struct e1000_hw *hw = &adapter->hw;
         struct pci_dev *pdev = adapter->pdev;
-        u32 rnbc;
+        u32 rnbc, reg;
         u16 phy_tmp;
         int i;
         u64 bytes, packets;
@@ -4072,8 +4072,13 @@ void igb_update_stats(struct igb_adapter *adapter)
         adapter->stats.colc += rd32(E1000_COLC);
 
         adapter->stats.algnerrc += rd32(E1000_ALGNERRC);
-        adapter->stats.rxerrc += rd32(E1000_RXERRC);
-        adapter->stats.tncrs += rd32(E1000_TNCRS);
+        /* read internal phy specific stats */
+        reg = rd32(E1000_CTRL_EXT);
+        if (!(reg & E1000_CTRL_EXT_LINK_MODE_MASK)) {
+                adapter->stats.rxerrc += rd32(E1000_RXERRC);
+                adapter->stats.tncrs += rd32(E1000_TNCRS);
+        }
+
         adapter->stats.tsctc += rd32(E1000_TSCTC);
         adapter->stats.tsctfc += rd32(E1000_TSCTFC);