igb: Program MDICNFG register prior to PHY init

This patch addresses an issue seen on 82580 in which the MDICNFG
register will be reset during a single function reset and as a
result we will be unable to communicate with the PHY.  To correct
the issue, added a call to reset_mdicnfg just prior to the first
access of the MDICNFG register in sgnii_uses_mdio.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 7 deletions

diff --git a/drivers/net/igb/e1000_82575.c b/drivers/net/igb/e1000_82575.c
index cc58227af42..187622f1c81 100644
--- a/drivers/net/igb/e1000_82575.c
+++ b/drivers/net/igb/e1000_82575.c
@@ -63,6 +63,7 @@ static bool igb_sgmii_active_82575(struct e1000_hw *);
 static s32  igb_reset_init_script_82575(struct e1000_hw *);
 static s32  igb_read_mac_addr_82575(struct e1000_hw *);
 static s32  igb_set_pcie_completion_timeout(struct e1000_hw *hw);
+static s32  igb_reset_mdicnfg_82580(struct e1000_hw *hw);
 
 static const u16 e1000_82580_rxpbs_table[] =
         { 36, 72, 144, 1, 2, 4, 8, 16,
@@ -159,20 +160,15 @@ static s32 igb_get_invariants_82575(struct e1000_hw *hw)
         switch (ctrl_ext & E1000_CTRL_EXT_LINK_MODE_MASK) {
         case E1000_CTRL_EXT_LINK_MODE_SGMII:
                 dev_spec->sgmii_active = true;
-                ctrl_ext |= E1000_CTRL_I2C_ENA;
                 break;
         case E1000_CTRL_EXT_LINK_MODE_1000BASE_KX:
         case E1000_CTRL_EXT_LINK_MODE_PCIE_SERDES:
                 hw->phy.media_type = e1000_media_type_internal_serdes;
-                ctrl_ext |= E1000_CTRL_I2C_ENA;
                 break;
         default:
-                ctrl_ext &= ~E1000_CTRL_I2C_ENA;
                 break;
         }
 
-        wr32(E1000_CTRL_EXT, ctrl_ext);
-
         /* Set mta register count */
         mac->mta_reg_count = 128;
         /* Set rar entry count */
@@ -250,11 +246,19 @@ static s32 igb_get_invariants_82575(struct e1000_hw *hw)
         phy->autoneg_mask        = AUTONEG_ADVERTISE_SPEED_DEFAULT;
         phy->reset_delay_us      = 100;
 
+        ctrl_ext = rd32(E1000_CTRL_EXT);
+
         /* PHY function pointers */
-        if (igb_sgmii_active_82575(hw))
+        if (igb_sgmii_active_82575(hw)) {
                 phy->ops.reset      = igb_phy_hw_reset_sgmii_82575;
-        else
+                ctrl_ext |= E1000_CTRL_I2C_ENA;
+        } else {
                 phy->ops.reset      = igb_phy_hw_reset;
+                ctrl_ext &= ~E1000_CTRL_I2C_ENA;
+        }
+
+        wr32(E1000_CTRL_EXT, ctrl_ext);
+        igb_reset_mdicnfg_82580(hw);
 
         if (igb_sgmii_active_82575(hw) && !igb_sgmii_uses_mdio_82575(hw)) {
                 phy->ops.read_reg   = igb_read_phy_reg_sgmii_82575;