e1000e: Expand workaround for 10Mb HD throughput bug

In commit 772d05c51c4f4896c120ad418b1e91144a2ac813 "e1000e: slow performance
between two 82579 connected via 10Mbit hub", a workaround was put into place
to address the overaggressive transmit behavior of 82579 parts when connecting
at 10Mbs half-duplex.

This same behavior is seen on i217 and i218 parts as well.  This patch expands
the original workaround to encompass these parts.

Signed-off-by: Dave Ertman <davidx.m.ertman@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

2 files changed, 12 insertions, 4 deletions

diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c
index 9b736b8625ae..059f1b0112f4 100644
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.c
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c
@@ -1314,14 +1314,17 @@ static s32 e1000_check_for_copper_link_ich8lan(struct e1000_hw *hw)
                         return ret_val;
         }
 
-        /* When connected at 10Mbps half-duplex, 82579 parts are excessively
+        /* When connected at 10Mbps half-duplex, some parts are excessively
          * aggressive resulting in many collisions. To avoid this, increase
          * the IPG and reduce Rx latency in the PHY.
          */
-        if ((hw->mac.type == e1000_pch2lan) && link) {
+        if (((hw->mac.type == e1000_pch2lan) ||
+             (hw->mac.type == e1000_pch_lpt)) && link) {
                 u32 reg;
                 reg = er32(STATUS);
                 if (!(reg & (E1000_STATUS_FD | E1000_STATUS_SPEED_MASK))) {
+                        u16 emi_addr;
+
                         reg = er32(TIPG);
                         reg &= ~E1000_TIPG_IPGT_MASK;
                         reg |= 0xFF;
@@ -1332,8 +1335,12 @@ static s32 e1000_check_for_copper_link_ich8lan(struct e1000_hw *hw)
                         if (ret_val)
                                 return ret_val;
 
-                        ret_val =
-                            e1000_write_emi_reg_locked(hw, I82579_RX_CONFIG, 0);
+                        if (hw->mac.type == e1000_pch2lan)
+                                emi_addr = I82579_RX_CONFIG;
+                        else
+                                emi_addr = I217_RX_CONFIG;
+
+                        ret_val = e1000_write_emi_reg_locked(hw, emi_addr, 0);
 
                         hw->phy.ops.release(hw);
 
diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.h b/drivers/net/ethernet/intel/e1000e/ich8lan.h
index bead50f9187b..8fc6c15f31c8 100644
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.h
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.h
@@ -242,6 +242,7 @@
 #define I217_EEE_CAPABILITY     0x8000  /* IEEE MMD Register 3.20 */
 #define I217_EEE_ADVERTISEMENT  0x8001  /* IEEE MMD Register 7.60 */
 #define I217_EEE_LP_ABILITY     0x8002  /* IEEE MMD Register 7.61 */
+#define I217_RX_CONFIG          0xB20C  /* Receive configuration */
 
 #define E1000_EEE_RX_LPI_RCVD   0x0400  /* Tx LP idle received */
 #define E1000_EEE_TX_LPI_RCVD   0x0800  /* Rx LP idle received */