ixgbe: Patch to fix 82599 multispeed fiber link issues when driver is loaded without any cable and reconnecting it to 1G partner

In 82599 multi speed fiber case when driver is loaded without any
cable and reconnecting the cable with a 1G partner does not bring
up the link in 1Gb mode. When there is no link we first setup the link
at 10G & 1G and then try to re-establish the link at highest speed 10G
and thereby changing autoneg_advertised value to highest speed 10G.
After connecting back the cable to a 1G link partner we never try 1G
as autoneg advertised value is changed to link at 10G only. The
following patch fixes the issue by properly initializing the
autoneg_advertised value just before exiting from link setup routine.

Signed-off-by: Mallikarjuna R Chilakala <mallikarjuna.chilakala@intel.com>
Acked-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ixgbe/ixgbe_82599.c

@@ -421,15 +421,6 @@ s32 ixgbe_setup_mac_link_multispeed_fiber(struct ixgbe_hw *hw,
 	hw->mac.ops.get_link_capabilities(hw, &phy_link_speed, &negotiation);
 	speed &= phy_link_speed;
 
-	 /* Set autoneg_advertised value based on input link speed */
-	hw->phy.autoneg_advertised = 0;
-
-	if (speed & IXGBE_LINK_SPEED_10GB_FULL)
-		hw->phy.autoneg_advertised |= IXGBE_LINK_SPEED_10GB_FULL;
-
-	if (speed & IXGBE_LINK_SPEED_1GB_FULL)
-		hw->phy.autoneg_advertised |= IXGBE_LINK_SPEED_1GB_FULL;
-
 	/*
 	 * When the driver changes the link speeds that it can support,
 	 * it sets autotry_restart to true to indicate that we need to
@@ -466,7 +457,7 @@ s32 ixgbe_setup_mac_link_multispeed_fiber(struct ixgbe_hw *hw,
 		                               autoneg,
 		                               autoneg_wait_to_complete);
 		if (status != 0)
-			goto out;
+			return status;
 
 		/* Flap the tx laser if it has not already been done */
 		if (hw->mac.autotry_restart) {
@@ -520,7 +511,7 @@ s32 ixgbe_setup_mac_link_multispeed_fiber(struct ixgbe_hw *hw,
 		                                      autoneg,
 		                                      autoneg_wait_to_complete);
 		if (status != 0)
-			goto out;
+			return status;
 
 		/* Flap the tx laser if it has not already been done */
 		if (hw->mac.autotry_restart) {
@@ -558,6 +549,15 @@ s32 ixgbe_setup_mac_link_multispeed_fiber(struct ixgbe_hw *hw,
 		                                               autoneg_wait_to_complete);
 
 out:
+	/* Set autoneg_advertised value based on input link speed */
+	hw->phy.autoneg_advertised = 0;
+
+	if (speed & IXGBE_LINK_SPEED_10GB_FULL)
+		hw->phy.autoneg_advertised |= IXGBE_LINK_SPEED_10GB_FULL;
+
+	if (speed & IXGBE_LINK_SPEED_1GB_FULL)
+		hw->phy.autoneg_advertised |= IXGBE_LINK_SPEED_1GB_FULL;
+
 	return status;
 }