e1000: omit stats for broken counter in 82543

The 82543 chip does not count tx_carrier_errors properly in FD mode;
report zeros instead of garbage.

Originally from Jesse Brandeburg <jesse.brandeburg@intel.com>, rewritten
to use feature flags by me.

Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index 62ef267b3d64..0816de267610 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -3581,6 +3581,11 @@ e1000_update_stats(struct e1000_adapter *adapter)
         adapter->net_stats.tx_aborted_errors = adapter->stats.ecol;
         adapter->net_stats.tx_window_errors = adapter->stats.latecol;
         adapter->net_stats.tx_carrier_errors = adapter->stats.tncrs;
+        if (adapter->hw.bad_tx_carr_stats_fd &&
+            adapter->link_duplex == FULL_DUPLEX) {
+                adapter->net_stats.tx_carrier_errors = 0;
+                adapter->stats.tncrs = 0;
+        }
 
         /* Tx Dropped needs to be maintained elsewhere */