ixgbe: disable link when adapter goes down

This patch fixes an issue with the 82599 adapter where it can potentially keep
link lights up when the adapter has gone down. The patch adds a function which
ensures link is disabled, and calls this function when the adapter transitions
to a down state.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_82599.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_82599.c
index 207f68f..51ee8ad 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_82599.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_82599.c
@@ -49,6 +49,7 @@
 static s32 ixgbe_setup_mac_link_smartspeed(struct ixgbe_hw *hw,
                                            ixgbe_link_speed speed,
                                            bool autoneg_wait_to_complete);
+static void ixgbe_stop_mac_link_on_d3_82599(struct ixgbe_hw *hw);
 static s32 ixgbe_start_mac_link_82599(struct ixgbe_hw *hw,
 				      bool autoneg_wait_to_complete);
 static s32 ixgbe_setup_mac_link_82599(struct ixgbe_hw *hw,
@@ -432,6 +433,24 @@
 }
 
 /**
+ * ixgbe_stop_mac_link_on_d3_82599 - Disables link on D3
+ * @hw: pointer to hardware structure
+ *
+ * Disables link, should be called during D3 power down sequence.
+ *
+ */
+static void ixgbe_stop_mac_link_on_d3_82599(struct ixgbe_hw *hw)
+{
+	u32 autoc2_reg;
+
+	if (!hw->mng_fw_enabled && !hw->wol_enabled) {
+		autoc2_reg = IXGBE_READ_REG(hw, IXGBE_AUTOC2);
+		autoc2_reg |= IXGBE_AUTOC2_LINK_DISABLE_ON_D3_MASK;
+		IXGBE_WRITE_REG(hw, IXGBE_AUTOC2, autoc2_reg);
+	}
+}
+
+/**
  *  ixgbe_start_mac_link_82599 - Setup MAC link settings
  *  @hw: pointer to hardware structure
  *  @autoneg_wait_to_complete: true when waiting for completion is needed
@@ -2477,6 +2496,7 @@
 	.set_lan_id             = &ixgbe_set_lan_id_multi_port_pcie,
 	.read_analog_reg8       = &ixgbe_read_analog_reg8_82599,
 	.write_analog_reg8      = &ixgbe_write_analog_reg8_82599,
+	.stop_link_on_d3	= &ixgbe_stop_mac_link_on_d3_82599,
 	.setup_link             = &ixgbe_setup_mac_link_82599,
 	.set_rxpba		= &ixgbe_set_rxpba_generic,
 	.check_link             = &ixgbe_check_mac_link_generic,
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 128d6b8..cf1b41e 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -5292,6 +5292,9 @@
 		return retval;
 
 #endif
+	if (hw->mac.ops.stop_link_on_d3)
+		hw->mac.ops.stop_link_on_d3(hw);
+
 	if (wufc) {
 		ixgbe_set_rx_mode(netdev);
 
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
index 161ff18..6442cf8 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
@@ -1596,6 +1596,7 @@
 #define IXGBE_AUTOC2_10G_KR  (0x0 << IXGBE_AUTOC2_10G_SERIAL_PMA_PMD_SHIFT)
 #define IXGBE_AUTOC2_10G_XFI (0x1 << IXGBE_AUTOC2_10G_SERIAL_PMA_PMD_SHIFT)
 #define IXGBE_AUTOC2_10G_SFI (0x2 << IXGBE_AUTOC2_10G_SERIAL_PMA_PMD_SHIFT)
+#define IXGBE_AUTOC2_LINK_DISABLE_ON_D3_MASK  0x50000000
 #define IXGBE_AUTOC2_LINK_DISABLE_MASK        0x70000000
 
 #define IXGBE_MACC_FLU       0x00000001
@@ -2847,6 +2848,7 @@
 	void (*disable_tx_laser)(struct ixgbe_hw *);
 	void (*enable_tx_laser)(struct ixgbe_hw *);
 	void (*flap_tx_laser)(struct ixgbe_hw *);
+	void (*stop_link_on_d3)(struct ixgbe_hw *);
 	s32 (*setup_link)(struct ixgbe_hw *, ixgbe_link_speed, bool);
 	s32 (*check_link)(struct ixgbe_hw *, ixgbe_link_speed *, bool *, bool);
 	s32 (*get_link_capabilities)(struct ixgbe_hw *, ixgbe_link_speed *,