e1000: 3 new driver stats for managability testing

Add 3 extra packet redirect counters for tracking purposes to make sure
we can test that all packets arrive properly.

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

Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/e1000/e1000_ethtool.c b/drivers/net/e1000/e1000_ethtool.c
index da459f7..fb96c87 100644
--- a/drivers/net/e1000/e1000_ethtool.c
+++ b/drivers/net/e1000/e1000_ethtool.c
@@ -100,6 +100,9 @@
 	{ "rx_csum_offload_errors", E1000_STAT(hw_csum_err) },
 	{ "rx_header_split", E1000_STAT(rx_hdr_split) },
 	{ "alloc_rx_buff_failed", E1000_STAT(alloc_rx_buff_failed) },
+	{ "tx_smbus", E1000_STAT(stats.mgptc) },
+	{ "rx_smbus", E1000_STAT(stats.mgprc) },
+	{ "dropped_smbus", E1000_STAT(stats.mgpdc) },
 };
 
 #define E1000_QUEUE_STATS_LEN 0
diff --git a/drivers/net/e1000/e1000_hw.c b/drivers/net/e1000/e1000_hw.c
index 5a6a61e..9be4469 100644
--- a/drivers/net/e1000/e1000_hw.c
+++ b/drivers/net/e1000/e1000_hw.c
@@ -458,6 +458,9 @@
 	if (hw->mac_type == e1000_80003es2lan)
 		hw->rx_needs_kicking = TRUE;
 
+	if (hw->mac_type > e1000_82544)
+		hw->has_smbus = TRUE;
+
 	return E1000_SUCCESS;
 }
 
diff --git a/drivers/net/e1000/e1000_hw.h b/drivers/net/e1000/e1000_hw.h
index 15b8625..d671058 100644
--- a/drivers/net/e1000/e1000_hw.h
+++ b/drivers/net/e1000/e1000_hw.h
@@ -1464,6 +1464,7 @@
 	boolean_t		bad_tx_carr_stats_fd;
 	boolean_t		has_manc2h;
 	boolean_t		rx_needs_kicking;
+	boolean_t		has_smbus;
 };
 
 
diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index 3f40a90..b06b51a 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -3743,6 +3743,13 @@
 			adapter->phy_stats.receive_errors += phy_tmp;
 	}
 
+	/* Management Stats */
+	if (adapter->hw.has_smbus) {
+		adapter->stats.mgptc += E1000_READ_REG(hw, MGTPTC);
+		adapter->stats.mgprc += E1000_READ_REG(hw, MGTPRC);
+		adapter->stats.mgpdc += E1000_READ_REG(hw, MGTPDC);
+	}
+
 	spin_unlock_irqrestore(&adapter->stats_lock, flags);
 }
 #ifdef CONFIG_PCI_MSI