igb: Power down link when interface is down

This changes the behavior of the driver to power down the link
when the associated interface is down, unless management is enabled.
Signed-off-by: Nicholas Nunley <nicholasx.d.nunley@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/igb/e1000_82575.c

@@ -726,6 +726,34 @@ static s32 igb_check_for_link_82575(struct e1000_hw *hw)
 	return ret_val;
 }
 
+/**
+ *  igb_power_up_serdes_link_82575 - Power up the serdes link after shutdown
+ *  @hw: pointer to the HW structure
+ **/
+void igb_power_up_serdes_link_82575(struct e1000_hw *hw)
+{
+	u32 reg;
+
+
+	if ((hw->phy.media_type != e1000_media_type_internal_serdes) &&
+	    !igb_sgmii_active_82575(hw))
+		return;
+
+	/* Enable PCS to turn on link */
+	reg = rd32(E1000_PCS_CFG0);
+	reg |= E1000_PCS_CFG_PCS_EN;
+	wr32(E1000_PCS_CFG0, reg);
+
+	/* Power up the laser */
+	reg = rd32(E1000_CTRL_EXT);
+	reg &= ~E1000_CTRL_EXT_SDP3_DATA;
+	wr32(E1000_CTRL_EXT, reg);
+
+	/* flush the write to verify completion */
+	wrfl();
+	msleep(1);
+}
+
 /**
  *  igb_get_pcs_speed_and_duplex_82575 - Retrieve current speed/duplex
  *  @hw: pointer to the HW structure
@@ -1165,6 +1193,22 @@ static s32 igb_read_mac_addr_82575(struct e1000_hw *hw)
 	return ret_val;
 }
 
+/**
+ * igb_power_down_phy_copper_82575 - Remove link during PHY power down
+ * @hw: pointer to the HW structure
+ *
+ * In the case of a PHY power down to save power, or to turn off link during a
+ * driver unload, or wake on lan is not enabled, remove the link.
+ **/
+void igb_power_down_phy_copper_82575(struct e1000_hw *hw)
+{
+	/* If the management interface is not enabled, then power down */
+	if (!(igb_enable_mng_pass_thru(hw) || igb_check_reset_block(hw)))
+		igb_power_down_phy_copper(hw);
+
+	return;
+}
+
 /**
  *  igb_clear_hw_cntrs_82575 - Clear device specific hardware counters
  *  @hw: pointer to the HW structure

drivers/net/igb/e1000_82575.h

@@ -29,6 +29,8 @@
 #define _E1000_82575_H_
 
 extern void igb_shutdown_serdes_link_82575(struct e1000_hw *hw);
+extern void igb_power_up_serdes_link_82575(struct e1000_hw *hw);
+extern void igb_power_down_phy_copper_82575(struct e1000_hw *hw);
 extern void igb_rx_fifo_flush_82575(struct e1000_hw *hw);
 
 #define ID_LED_DEFAULT_82575_SERDES ((ID_LED_DEF1_DEF2 << 12) | \

drivers/net/igb/e1000_defines.h

@@ -481,6 +481,7 @@
 /* PHY Control Register */
 #define MII_CR_FULL_DUPLEX      0x0100  /* FDX =1, half duplex =0 */
 #define MII_CR_RESTART_AUTO_NEG 0x0200  /* Restart auto negotiation */
+#define MII_CR_POWER_DOWN       0x0800  /* Power down */
 #define MII_CR_AUTO_NEG_EN      0x1000  /* Auto Neg Enable */
 #define MII_CR_LOOPBACK         0x4000  /* 0 = normal, 1 = loopback */
 #define MII_CR_RESET            0x8000  /* 0 = normal, 1 = PHY reset */

drivers/net/igb/e1000_phy.c

@@ -1930,6 +1930,41 @@ s32 igb_phy_init_script_igp3(struct e1000_hw *hw)
 	return 0;
 }
 
+/**
+ * igb_power_up_phy_copper - Restore copper link in case of PHY power down
+ * @hw: pointer to the HW structure
+ *
+ * In the case of a PHY power down to save power, or to turn off link during a
+ * driver unload, restore the link to previous settings.
+ **/
+void igb_power_up_phy_copper(struct e1000_hw *hw)
+{
+	u16 mii_reg = 0;
+
+	/* The PHY will retain its settings across a power down/up cycle */
+	hw->phy.ops.read_reg(hw, PHY_CONTROL, &mii_reg);
+	mii_reg &= ~MII_CR_POWER_DOWN;
+	hw->phy.ops.write_reg(hw, PHY_CONTROL, mii_reg);
+}
+
+/**
+ * igb_power_down_phy_copper - Power down copper PHY
+ * @hw: pointer to the HW structure
+ *
+ * Power down PHY to save power when interface is down and wake on lan
+ * is not enabled.
+ **/
+void igb_power_down_phy_copper(struct e1000_hw *hw)
+{
+	u16 mii_reg = 0;
+
+	/* The PHY will retain its settings across a power down/up cycle */
+	hw->phy.ops.read_reg(hw, PHY_CONTROL, &mii_reg);
+	mii_reg |= MII_CR_POWER_DOWN;
+	hw->phy.ops.write_reg(hw, PHY_CONTROL, mii_reg);
+	msleep(1);
+}
+
 /**
  *  igb_check_polarity_82580 - Checks the polarity.
  *  @hw: pointer to the HW structure

drivers/net/igb/e1000_phy.h

@@ -60,6 +60,8 @@ s32  igb_setup_copper_link(struct e1000_hw *hw);
 s32  igb_write_phy_reg_igp(struct e1000_hw *hw, u32 offset, u16 data);
 s32  igb_phy_has_link(struct e1000_hw *hw, u32 iterations,
 				u32 usec_interval, bool *success);
+void igb_power_up_phy_copper(struct e1000_hw *hw);
+void igb_power_down_phy_copper(struct e1000_hw *hw);
 s32  igb_phy_init_script_igp3(struct e1000_hw *hw);
 s32  igb_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data);
 s32  igb_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data);

drivers/net/igb/igb.h

@@ -358,6 +358,7 @@ extern void igb_alloc_rx_buffers_adv(struct igb_ring *, int);
 extern void igb_update_stats(struct igb_adapter *);
 extern bool igb_has_link(struct igb_adapter *adapter);
 extern void igb_set_ethtool_ops(struct net_device *);
+extern void igb_power_up_link(struct igb_adapter *);
 
 static inline s32 igb_reset_phy(struct e1000_hw *hw)
 {

drivers/net/igb/igb_ethtool.c

@@ -1722,6 +1722,9 @@ static void igb_diag_test(struct net_device *netdev,
 
 		dev_info(&adapter->pdev->dev, "offline testing starting\n");
 
+		/* power up link for link test */
+		igb_power_up_link(adapter);
+
 		/* Link test performed before hardware reset so autoneg doesn't
 		 * interfere with test result */
 		if (igb_link_test(adapter, &data[4]))
@@ -1745,6 +1748,8 @@ static void igb_diag_test(struct net_device *netdev,
 			eth_test->flags |= ETH_TEST_FL_FAILED;
 
 		igb_reset(adapter);
+		/* power up link for loopback test */
+		igb_power_up_link(adapter);
 		if (igb_loopback_test(adapter, &data[3]))
 			eth_test->flags |= ETH_TEST_FL_FAILED;
 
@@ -1763,9 +1768,14 @@ static void igb_diag_test(struct net_device *netdev,
 			dev_open(netdev);
 	} else {
 		dev_info(&adapter->pdev->dev, "online testing starting\n");
-		/* Online tests */
+
+		/* PHY is powered down when interface is down */
+		if (!netif_carrier_ok(netdev)) {
+			data[4] = 0;
+		} else {
 			if (igb_link_test(adapter, &data[4]))
 				eth_test->flags |= ETH_TEST_FL_FAILED;
+		}
 
 		/* Online tests aren't run; pass by default */
 		data[0] = 0;

drivers/net/igb/igb_main.c

@@ -1114,6 +1114,29 @@ static void igb_configure(struct igb_adapter *adapter)
 	adapter->tx_queue_len = netdev->tx_queue_len;
 }
 
+/**
+ * igb_power_up_link - Power up the phy/serdes link
+ * @adapter: address of board private structure
+ **/
+void igb_power_up_link(struct igb_adapter *adapter)
+{
+	if (adapter->hw.phy.media_type == e1000_media_type_copper)
+		igb_power_up_phy_copper(&adapter->hw);
+	else
+		igb_power_up_serdes_link_82575(&adapter->hw);
+}
+
+/**
+ * igb_power_down_link - Power down the phy/serdes link
+ * @adapter: address of board private structure
+ */
+static void igb_power_down_link(struct igb_adapter *adapter)
+{
+	if (adapter->hw.phy.media_type == e1000_media_type_copper)
+		igb_power_down_phy_copper_82575(&adapter->hw);
+	else
+		igb_shutdown_serdes_link_82575(&adapter->hw);
+}
 
 /**
  * igb_up - Open the interface and prepare it to handle traffic
@@ -1335,6 +1358,9 @@ void igb_reset(struct igb_adapter *adapter)
 		wr32(E1000_PCIEMISC,
 		                reg & ~E1000_PCIEMISC_LX_DECISION);
 	}
+	if (!netif_running(adapter->netdev))
+		igb_power_down_link(adapter);
+
 	igb_update_mng_vlan(adapter);
 
 	/* Enable h/w to recognize an 802.1Q VLAN Ethernet packet */
@@ -1717,9 +1743,6 @@ static void __devexit igb_remove(struct pci_dev *pdev)
 
 	unregister_netdev(netdev);
 
-	if (!igb_check_reset_block(hw))
-		igb_reset_phy(hw);
-
 	igb_clear_interrupt_scheme(adapter);
 
 #ifdef CONFIG_PCI_IOV
@@ -1995,7 +2018,7 @@ static int igb_open(struct net_device *netdev)
 	if (err)
 		goto err_setup_rx;
 
-	/* e1000_power_up_phy(adapter); */
+	igb_power_up_link(adapter);
 
 	/* before we allocate an interrupt, we must be ready to handle it.
 	 * Setting DEBUG_SHIRQ in the kernel makes it fire an interrupt
@@ -2037,7 +2060,7 @@ static int igb_open(struct net_device *netdev)
 
 err_req_irq:
 	igb_release_hw_control(adapter);
-	/* e1000_power_down_phy(adapter); */
+	igb_power_down_link(adapter);
 	igb_free_all_rx_resources(adapter);
 err_setup_rx:
 	igb_free_all_tx_resources(adapter);
@@ -5820,7 +5843,9 @@ static int __igb_shutdown(struct pci_dev *pdev, bool *enable_wake)
 
 	*enable_wake = wufc || adapter->en_mng_pt;
 	if (!*enable_wake)
-		igb_shutdown_serdes_link_82575(hw);
+		igb_power_down_link(adapter);
+	else
+		igb_power_up_link(adapter);
 
 	/* Release control of h/w to f/w.  If f/w is AMT enabled, this
 	 * would have already happened in close and is redundant. */
@@ -5877,8 +5902,6 @@ static int igb_resume(struct pci_dev *pdev)
 		return -ENOMEM;
 	}
 
-	/* e1000_power_up_phy(adapter); */
-
 	igb_reset(adapter);
 
 	/* let the f/w know that the h/w is now under the control of the