e1000/base: fix TIPG for non 10 half duplex mode

TIPG value is increased when setting speed to 10 half to prevent
packet loss. However, it was never decreased again when speed
changes. This caused performance issues in the NDIS driver.
Fix this to restore TIPG to default value on non 10 half.

Signed-off-by: Wenzhuo Lu <wenzhuo.lu@intel.com>

diff --git a/drivers/net/e1000/base/e1000_ich8lan.c b/drivers/net/e1000/base/e1000_ich8lan.c
index 103b41a..60c31c2 100644 (file)
--- a/drivers/net/e1000/base/e1000_ich8lan.c
+++ b/drivers/net/e1000/base/e1000_ich8lan.c
@@ -1390,7 +1390,8 @@ out:
 STATIC s32 e1000_check_for_copper_link_ich8lan(struct e1000_hw *hw)
 {
        struct e1000_mac_info *mac = &hw->mac;
-       s32 ret_val;
+       s32 ret_val, tipg_reg = 0;
+       u16 emi_addr, emi_val = 0;
        bool link = false;
        u16 phy_reg;
 
@@ -1440,32 +1441,38 @@ STATIC s32 e1000_check_for_copper_link_ich8lan(struct e1000_hw *hw)
         */
        if (((hw->mac.type == e1000_pch2lan) ||
             (hw->mac.type == e1000_pch_lpt)) && link) {
-               u32 reg;
-               reg = E1000_READ_REG(hw, E1000_STATUS);
-               if (!(reg & (E1000_STATUS_FD | E1000_STATUS_SPEED_MASK))) {
-                       u16 emi_addr;
+               u16 speed, duplex;
 
-                       reg = E1000_READ_REG(hw, E1000_TIPG);
-                       reg &= ~E1000_TIPG_IPGT_MASK;
-                       reg |= 0xFF;
-                       E1000_WRITE_REG(hw, E1000_TIPG, reg);
+               e1000_get_speed_and_duplex_copper_generic(hw, &speed, &duplex);
+               tipg_reg = E1000_READ_REG(hw, E1000_TIPG);
+               tipg_reg &= ~E1000_TIPG_IPGT_MASK;
 
+               if (duplex == HALF_DUPLEX && speed == SPEED_10) {
+                       tipg_reg |= 0xFF;
                        /* Reduce Rx latency in analog PHY */
-                       ret_val = hw->phy.ops.acquire(hw);
-                       if (ret_val)
-                               return ret_val;
+                       emi_val = 0;
+               } else {
+                       /* Roll back the default values */
+                       tipg_reg |= 0x08;
+                       emi_val = 1;
+               }
 
-                       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);
+               E1000_WRITE_REG(hw, E1000_TIPG, tipg_reg);
 
-                       hw->phy.ops.release(hw);
+               ret_val = hw->phy.ops.acquire(hw);
+               if (ret_val)
+                       return ret_val;
 
-                       if (ret_val)
-                               return ret_val;
-               }
+               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, emi_val);
+
+               hw->phy.ops.release(hw);
+
+               if (ret_val)
+                       return ret_val;
        }
 
        /* Work-around I218 hang issue */