[PATCH] e1000: Set Attla PHY to Class A

Some LOM implementation of our controllers pass IEEE tests (Tx 
distortion/Symmetry) while operating in Class A mode rather than in
class AB mode.

drivers/net/e1000/e1000_hw.c

@@ -65,6 +65,7 @@ static void e1000_release_eeprom(struct e1000_hw *hw);
 static void e1000_standby_eeprom(struct e1000_hw *hw);
 static int32_t e1000_id_led_init(struct e1000_hw * hw);
 static int32_t e1000_set_vco_speed(struct e1000_hw *hw);
+static int32_t e1000_set_phy_mode(struct e1000_hw *hw);
 
 /* IGP cable length table */
 static const
@@ -899,6 +900,11 @@ e1000_setup_copper_link(struct e1000_hw *hw)
     }
     DEBUGOUT1("Phy ID = %x \n", hw->phy_id);
 
+    /* Set PHY to class A mode (if necessary) */
+    ret_val = e1000_set_phy_mode(hw);
+    if(ret_val)
+        return ret_val;
+
     if(hw->mac_type <= e1000_82543 ||
        hw->mac_type == e1000_82541 || hw->mac_type == e1000_82547 ||
        hw->mac_type == e1000_82541_rev_2 || hw->mac_type == e1000_82547_rev_2)
@@ -4905,6 +4911,45 @@ e1000_config_dsp_after_link_change(struct e1000_hw *hw,
     return E1000_SUCCESS;
 }
 
+/*****************************************************************************
+ * Set PHY to class A mode
+ * Assumes the following operations will follow to enable the new class mode.
+ *  1. Do a PHY soft reset
+ *  2. Restart auto-negotiation or force link.
+ *
+ * hw - Struct containing variables accessed by shared code
+ ****************************************************************************/
+static int32_t
+e1000_set_phy_mode(struct e1000_hw *hw)
+{
+    int32_t ret_val;
+    uint16_t eeprom_data;
+
+    DEBUGFUNC("e1000_set_phy_mode");
+
+    if((hw->mac_type == e1000_82545_rev_3) &&
+       (hw->media_type == e1000_media_type_copper)) {
+        ret_val = e1000_read_eeprom(hw, EEPROM_PHY_CLASS_WORD, 1, &eeprom_data);
+        if(ret_val) {
+            return ret_val;
+        }
+
+        if((eeprom_data != EEPROM_RESERVED_WORD) &&
+           (eeprom_data & EEPROM_PHY_CLASS_A)) {
+            ret_val = e1000_write_phy_reg(hw, M88E1000_PHY_PAGE_SELECT, 0x000B);
+            if(ret_val)
+                return ret_val;
+            ret_val = e1000_write_phy_reg(hw, M88E1000_PHY_GEN_CONTROL, 0x8104);
+            if(ret_val)
+                return ret_val;
+
+            hw->phy_reset_disable = FALSE;
+        }
+    }
+
+    return E1000_SUCCESS;
+}
+
 /*****************************************************************************
  *
  * This function sets the lplu state according to the active flag.  When

drivers/net/e1000/e1000_hw.h

@@ -1480,6 +1480,7 @@ struct e1000_hw {
 #define EEPROM_COMPAT                 0x0003
 #define EEPROM_ID_LED_SETTINGS        0x0004
 #define EEPROM_SERDES_AMPLITUDE       0x0006 /* For SERDES output amplitude adjustment. */
+#define EEPROM_PHY_CLASS_WORD         0x0007
 #define EEPROM_INIT_CONTROL1_REG      0x000A
 #define EEPROM_INIT_CONTROL2_REG      0x000F
 #define EEPROM_INIT_CONTROL3_PORT_B   0x0014
@@ -1513,6 +1514,9 @@ struct e1000_hw {
 /* Mask bits for SERDES amplitude adjustment in Word 6 of the EEPROM */
 #define EEPROM_SERDES_AMPLITUDE_MASK  0x000F
 
+/* Mask bit for PHY class in Word 7 of the EEPROM */
+#define EEPROM_PHY_CLASS_A   0x8000
+
 /* Mask bits for fields in Word 0x0a of the EEPROM */
 #define EEPROM_WORD0A_ILOS   0x0010
 #define EEPROM_WORD0A_SWDPIO 0x01E0