igb: Clear Go Link Disconnect for 82580 and later devices

Customers are requesting that the hw prevents PHY from establishing link
until the driver loads.  This patch clears the Go Link Disconnect bit which
provides the requested behavior on parts 82580 and later.

Signed-off-by: Carolyn Wyborny <carolyn.wyborny@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/igb/e1000_82575.c b/drivers/net/ethernet/intel/igb/e1000_82575.c
index deb05970b9f1..8c12dbd0d6ce 100644
--- a/drivers/net/ethernet/intel/igb/e1000_82575.c
+++ b/drivers/net/ethernet/intel/igb/e1000_82575.c
@@ -1278,12 +1278,20 @@ static s32 igb_setup_copper_link_82575(struct e1000_hw *hw)
 {
         u32 ctrl;
         s32  ret_val;
+        u32 phpm_reg;
 
         ctrl = rd32(E1000_CTRL);
         ctrl |= E1000_CTRL_SLU;
         ctrl &= ~(E1000_CTRL_FRCSPD | E1000_CTRL_FRCDPX);
         wr32(E1000_CTRL, ctrl);
 
+        /* Clear Go Link Disconnect bit */
+        if (hw->mac.type >= e1000_82580) {
+                phpm_reg = rd32(E1000_82580_PHY_POWER_MGMT);
+                phpm_reg &= ~E1000_82580_PM_GO_LINKD;
+                wr32(E1000_82580_PHY_POWER_MGMT, phpm_reg);
+        }
+
         ret_val = igb_setup_serdes_link_82575(hw);
         if (ret_val)
                 goto out;