e1000e: disable K1 on PCH LOM when in PHY loopback mode

When performing the ethtool PHY loopback test on PCH-based LOMs (82577 and
82578), disable K1 (a MAC-PHY interconnect low power mode) otherwise
packets might get corrupted.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 6 insertions, 2 deletions

diff --git a/drivers/net/e1000e/e1000.h b/drivers/net/e1000e/e1000.h
index 00989c5534c1..a6c68039e8d9 100644
--- a/drivers/net/e1000e/e1000.h
+++ b/drivers/net/e1000e/e1000.h
@@ -485,6 +485,7 @@ extern void e1000e_set_kmrn_lock_loss_workaround_ich8lan(struct e1000_hw *hw,
 extern void e1000e_igp3_phy_powerdown_workaround_ich8lan(struct e1000_hw *hw);
 extern void e1000e_gig_downshift_workaround_ich8lan(struct e1000_hw *hw);
 extern void e1000e_disable_gig_wol_ich8lan(struct e1000_hw *hw);
+extern s32 e1000_configure_k1_ich8lan(struct e1000_hw *hw, bool k1_enable);
 
 extern s32 e1000e_check_for_copper_link(struct e1000_hw *hw);
 extern s32 e1000e_check_for_fiber_link(struct e1000_hw *hw);
diff --git a/drivers/net/e1000e/ethtool.c b/drivers/net/e1000e/ethtool.c
index 67e06fd9fc45..fd7921482d2b 100644
--- a/drivers/net/e1000e/ethtool.c
+++ b/drivers/net/e1000e/ethtool.c
@@ -1260,6 +1260,10 @@ static int e1000_integrated_phy_loopback(struct e1000_adapter *adapter)
 
         hw->mac.autoneg = 0;
 
+        /* Workaround: K1 must be disabled for stable 1Gbps operation */
+        if (hw->mac.type == e1000_pchlan)
+                e1000_configure_k1_ich8lan(hw, false);
+
         if (hw->phy.type == e1000_phy_m88) {
                 /* Auto-MDI/MDIX Off */
                 e1e_wphy(hw, M88E1000_PHY_SPEC_CTRL, 0x0808);
diff --git a/drivers/net/e1000e/ich8lan.c b/drivers/net/e1000e/ich8lan.c
index 51ddb04ab195..bd9002e72cb6 100644
--- a/drivers/net/e1000e/ich8lan.c
+++ b/drivers/net/e1000e/ich8lan.c
@@ -224,7 +224,6 @@ static s32 e1000_led_off_pchlan(struct e1000_hw *hw);
 static s32 e1000_set_lplu_state_pchlan(struct e1000_hw *hw, bool active);
 static void e1000_lan_init_done_ich8lan(struct e1000_hw *hw);
 static s32  e1000_k1_gig_workaround_hv(struct e1000_hw *hw, bool link);
-static s32 e1000_configure_k1_ich8lan(struct e1000_hw *hw, bool k1_enable);
 
 static inline u16 __er16flash(struct e1000_hw *hw, unsigned long reg)
 {
@@ -1023,7 +1022,7 @@ out:
  *
  *  Success returns 0, Failure returns -E1000_ERR_PHY (-2)
  **/
-static s32 e1000_configure_k1_ich8lan(struct e1000_hw *hw, bool k1_enable)
+s32 e1000_configure_k1_ich8lan(struct e1000_hw *hw, bool k1_enable)
 {
         s32 ret_val = 0;
         u32 ctrl_reg = 0;