ixgbe: Add support for entering low power link up state

When the device is closing or suspending, call ixgbe_enter_lplu to
enter low power link up state on devices that support it. When this
is done, prevent the phy from being reset in the ixgbe_down path
so that link is present when calling ixgbe_enter_lplu.

Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

3 files changed, 185 insertions, 2 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index dcf849ddb7ce..098c84955a11 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -5798,7 +5798,15 @@ static void ixgbe_close_suspend(struct ixgbe_adapter *adapter)
 {
 	ixgbe_ptp_suspend(adapter);
 
-	ixgbe_down(adapter);
+	if (adapter->hw.phy.ops.enter_lplu) {
+		adapter->hw.phy.reset_disable = true;
+		ixgbe_down(adapter);
+		adapter->hw.phy.ops.enter_lplu(&adapter->hw);
+		adapter->hw.phy.reset_disable = false;
+	} else {
+		ixgbe_down(adapter);
+	}
+
 	ixgbe_free_irq(adapter);
 
 	ixgbe_free_all_tx_resources(adapter);
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
index 0e678243abf7..19271e5d2010 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
@@ -848,6 +848,7 @@ struct ixgbe_thermal_sensor_data {
 #define IXGBE_MDIO_AUTO_NEG_LINK_STATUS	0x4 /* Indicates if link is up */
 
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_MASK	0x7 /* Speed/Duplex Mask */
+#define IXGBE_MDIO_AUTO_NEG_VEN_STAT_SPEED_MASK	0x6 /* Speed Mask */
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_10M_HALF 0x0 /* 10Mb/s Half Duplex */
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_10M_FULL 0x1 /* 10Mb/s Full Duplex */
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_100M_HALF 0x2 /* 100Mb/s H Duplex */
@@ -856,6 +857,24 @@ struct ixgbe_thermal_sensor_data {
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_1GB_FULL 0x5 /* 1Gb/s Full Duplex */
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_10GB_HALF 0x6 /* 10Gb/s Half Duplex */
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_10GB_FULL 0x7 /* 10Gb/s Full Duplex */
+#define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_1GB	0x4 /* 1Gb/s */
+#define IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_10GB	0x6 /* 10Gb/s */
+
+#define IXGBE_MII_10GBASE_T_AUTONEG_CTRL_REG	0x20	/* 10G Control Reg */
+#define IXGBE_MII_AUTONEG_VENDOR_PROVISION_1_REG 0xC400	/* 1G Provisioning 1 */
+#define IXGBE_MII_AUTONEG_XNP_TX_REG		0x17	/* 1G XNP Transmit */
+#define IXGBE_MII_AUTONEG_ADVERTISE_REG		0x10	/* 100M Advertisement */
+#define IXGBE_MII_10GBASE_T_ADVERTISE		0x1000	/* full duplex, bit:12*/
+#define IXGBE_MII_1GBASE_T_ADVERTISE_XNP_TX	0x4000	/* full duplex, bit:14*/
+#define IXGBE_MII_1GBASE_T_ADVERTISE		0x8000	/* full duplex, bit:15*/
+#define IXGBE_MII_2_5GBASE_T_ADVERTISE		0x0400
+#define IXGBE_MII_5GBASE_T_ADVERTISE		0x0800
+#define IXGBE_MII_100BASE_T_ADVERTISE		0x0100	/* full duplex, bit:8 */
+#define IXGBE_MII_100BASE_T_ADVERTISE_HALF	0x0080	/* half duplex, bit:7 */
+#define IXGBE_MII_RESTART			0x200
+#define IXGBE_MII_AUTONEG_COMPLETE		0x20
+#define IXGBE_MII_AUTONEG_LINK_UP		0x04
+#define IXGBE_MII_AUTONEG_REG			0x0
 
 /* Management */
 #define IXGBE_MAVTV(_i) (0x05010 + ((_i) * 4)) /* 8 of these (0-7) */
@@ -1305,6 +1324,7 @@ struct ixgbe_thermal_sensor_data {
 #define IXGBE_MDIO_AUTO_NEG_CONTROL	0x0 /* AUTO_NEG Control Reg */
 #define IXGBE_MDIO_AUTO_NEG_STATUS	0x1 /* AUTO_NEG Status Reg */
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_STAT	0xC800 /* AUTO_NEG Vendor Status Reg */
+#define IXGBE_MDIO_AUTO_NEG_VENDOR_TX_ALARM  0xCC00 /* AUTO_NEG Vendor TX Reg */
 #define IXGBE_MDIO_AUTO_NEG_VENDOR_TX_ALARM2 0xCC01 /* AUTO_NEG Vendor Tx Reg */
 #define IXGBE_MDIO_AUTO_NEG_VEN_LSC	0x1 /* AUTO_NEG Vendor Tx LSC */
 #define IXGBE_MDIO_AUTO_NEG_ADVT	0x10 /* AUTO_NEG Advt Reg */
@@ -1312,7 +1332,8 @@ struct ixgbe_thermal_sensor_data {
 #define IXGBE_MDIO_AUTO_NEG_EEE_ADVT	0x3C /* AUTO_NEG EEE Advt Reg */
 
 #define IXGBE_MDIO_PHY_SET_LOW_POWER_MODE	 0x0800 /* Set low power mode */
-
+#define IXGBE_AUTO_NEG_LP_STATUS	0xE820 /* AUTO NEG Rx LP Status Reg */
+#define IXGBE_AUTO_NEG_LP_1000BASE_CAP	0x8000 /* AUTO NEG Rx LP 1000BaseT */
 #define IXGBE_MDIO_TX_VENDOR_ALARMS_3	0xCC02 /* Vendor Alarms 3 Reg */
 #define IXGBE_MDIO_TX_VENDOR_ALARMS_3_RST_MASK 0x3 /* PHY Reset Complete Mask */
 #define IXGBE_MDIO_GLOBAL_RES_PR_10 0xC479 /* Global Resv Provisioning 10 Reg */
@@ -2041,6 +2062,11 @@ enum {
 #define IXGBE_NVM_POLL_WRITE       1  /* Flag for polling for write complete */
 #define IXGBE_NVM_POLL_READ        0  /* Flag for polling for read complete */
 
+#define NVM_INIT_CTRL_3			0x38
+#define NVM_INIT_CTRL_3_LPLU		0x8
+#define NVM_INIT_CTRL_3_D10GMP_PORT0	0x40
+#define NVM_INIT_CTRL_3_D10GMP_PORT1	0x100
+
 #define IXGBE_EEPROM_PAGE_SIZE_MAX       128
 #define IXGBE_EEPROM_RD_BUFFER_MAX_COUNT 512 /* EEPROM words # read in burst */
 #define IXGBE_EEPROM_WR_BUFFER_MAX_COUNT 256 /* EEPROM words # wr in burst */
@@ -3301,6 +3327,7 @@ struct ixgbe_phy_operations {
 	s32 (*write_i2c_combined)(struct ixgbe_hw *, u8 addr, u16 reg, u16 val);
 	s32 (*check_overtemp)(struct ixgbe_hw *);
 	s32 (*set_phy_power)(struct ixgbe_hw *, bool on);
+	s32 (*enter_lplu)(struct ixgbe_hw *);
 	s32 (*handle_lasi)(struct ixgbe_hw *hw);
 };
 
@@ -3311,6 +3338,7 @@ struct ixgbe_eeprom_info {
 	u16                             word_size;
 	u16                             address_bits;
 	u16                             word_page_size;
+	u16				ctrl_word_3;
 };
 
 #define IXGBE_FLAGS_DOUBLE_RESET_REQUIRED	0x01
@@ -3466,6 +3494,10 @@ struct ixgbe_info {
 #define IXGBE_ERR_FDIR_CMD_INCOMPLETE		-38
 #define IXGBE_NOT_IMPLEMENTED                   0x7FFFFFFF
 
+#define IXGBE_FUSES0_GROUP(_i)		(0x11158 + ((_i) * 4))
+#define IXGBE_FUSES0_300MHZ		BIT(5)
+#define IXGBE_FUSES0_REV1		BIT(6)
+
 #define IXGBE_KRM_PORT_CAR_GEN_CTRL(P)	((P) ? 0x8010 : 0x4010)
 #define IXGBE_KRM_LINK_CTRL_1(P)	((P) ? 0x820C : 0x420C)
 #define IXGBE_KRM_DSP_TXFFE_STATE_4(P)	((P) ? 0x8634 : 0x4634)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c
index 662d2e896286..bbc5a2da86c4 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c
@@ -1458,6 +1458,144 @@ static s32 ixgbe_reset_phy_t_X550em(struct ixgbe_hw *hw)
 	return ixgbe_enable_lasi_ext_t_x550em(hw);
 }
 
+/** ixgbe_get_lcd_x550em - Determine lowest common denominator
+ *  @hw: pointer to hardware structure
+ *  @lcd_speed: pointer to lowest common link speed
+ *
+ *  Determine lowest common link speed with link partner.
+ **/
+static s32 ixgbe_get_lcd_t_x550em(struct ixgbe_hw *hw,
+				  ixgbe_link_speed *lcd_speed)
+{
+	u16 an_lp_status;
+	s32 status;
+	u16 word = hw->eeprom.ctrl_word_3;
+
+	*lcd_speed = IXGBE_LINK_SPEED_UNKNOWN;
+
+	status = hw->phy.ops.read_reg(hw, IXGBE_AUTO_NEG_LP_STATUS,
+				      IXGBE_MDIO_AUTO_NEG_DEV_TYPE,
+				      &an_lp_status);
+	if (status)
+		return status;
+
+	/* If link partner advertised 1G, return 1G */
+	if (an_lp_status & IXGBE_AUTO_NEG_LP_1000BASE_CAP) {
+		*lcd_speed = IXGBE_LINK_SPEED_1GB_FULL;
+		return status;
+	}
+
+	/* If 10G disabled for LPLU via NVM D10GMP, then return no valid LCD */
+	if ((hw->bus.lan_id && (word & NVM_INIT_CTRL_3_D10GMP_PORT1)) ||
+	    (word & NVM_INIT_CTRL_3_D10GMP_PORT0))
+		return status;
+
+	/* Link partner not capable of lower speeds, return 10G */
+	*lcd_speed = IXGBE_LINK_SPEED_10GB_FULL;
+	return status;
+}
+
+/** ixgbe_enter_lplu_x550em - Transition to low power states
+ *  @hw: pointer to hardware structure
+ *
+ *  Configures Low Power Link Up on transition to low power states
+ *  (from D0 to non-D0). Link is required to enter LPLU so avoid resetting
+ *  the X557 PHY immediately prior to entering LPLU.
+ **/
+static s32 ixgbe_enter_lplu_t_x550em(struct ixgbe_hw *hw)
+{
+	u16 an_10g_cntl_reg, autoneg_reg, speed;
+	s32 status;
+	ixgbe_link_speed lcd_speed;
+	u32 save_autoneg;
+	bool link_up;
+
+	/* SW LPLU not required on later HW revisions. */
+	if (IXGBE_FUSES0_REV1 & IXGBE_READ_REG(hw, IXGBE_FUSES0_GROUP(0)))
+		return 0;
+
+	/* If blocked by MNG FW, then don't restart AN */
+	if (ixgbe_check_reset_blocked(hw))
+		return 0;
+
+	status = ixgbe_ext_phy_t_x550em_get_link(hw, &link_up);
+	if (status)
+		return status;
+
+	status = hw->eeprom.ops.read(hw, NVM_INIT_CTRL_3,
+				     &hw->eeprom.ctrl_word_3);
+	if (status)
+		return status;
+
+	/* If link is down, LPLU disabled in NVM, WoL disabled, or
+	 * manageability disabled, then force link down by entering
+	 * low power mode.
+	 */
+	if (!link_up || !(hw->eeprom.ctrl_word_3 & NVM_INIT_CTRL_3_LPLU) ||
+	    !(hw->wol_enabled || ixgbe_mng_present(hw)))
+		return ixgbe_set_copper_phy_power(hw, false);
+
+	/* Determine LCD */
+	status = ixgbe_get_lcd_t_x550em(hw, &lcd_speed);
+	if (status)
+		return status;
+
+	/* If no valid LCD link speed, then force link down and exit. */
+	if (lcd_speed == IXGBE_LINK_SPEED_UNKNOWN)
+		return ixgbe_set_copper_phy_power(hw, false);
+
+	status = hw->phy.ops.read_reg(hw, IXGBE_MDIO_AUTO_NEG_VENDOR_STAT,
+				      IXGBE_MDIO_AUTO_NEG_DEV_TYPE,
+				      &speed);
+	if (status)
+		return status;
+
+	/* If no link now, speed is invalid so take link down */
+	status = ixgbe_ext_phy_t_x550em_get_link(hw, &link_up);
+	if (status)
+		return ixgbe_set_copper_phy_power(hw, false);
+
+	/* clear everything but the speed bits */
+	speed &= IXGBE_MDIO_AUTO_NEG_VEN_STAT_SPEED_MASK;
+
+	/* If current speed is already LCD, then exit. */
+	if (((speed == IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_1GB) &&
+	     (lcd_speed == IXGBE_LINK_SPEED_1GB_FULL)) ||
+	    ((speed == IXGBE_MDIO_AUTO_NEG_VENDOR_STATUS_10GB) &&
+	     (lcd_speed == IXGBE_LINK_SPEED_10GB_FULL)))
+		return status;
+
+	/* Clear AN completed indication */
+	status = hw->phy.ops.read_reg(hw, IXGBE_MDIO_AUTO_NEG_VENDOR_TX_ALARM,
+				      IXGBE_MDIO_AUTO_NEG_DEV_TYPE,
+				      &autoneg_reg);
+	if (status)
+		return status;
+
+	status = hw->phy.ops.read_reg(hw, IXGBE_MII_10GBASE_T_AUTONEG_CTRL_REG,
+				      IXGBE_MDIO_AUTO_NEG_DEV_TYPE,
+				      &an_10g_cntl_reg);
+	if (status)
+		return status;
+
+	status = hw->phy.ops.read_reg(hw,
+				      IXGBE_MII_AUTONEG_VENDOR_PROVISION_1_REG,
+				      IXGBE_MDIO_AUTO_NEG_DEV_TYPE,
+				      &autoneg_reg);
+	if (status)
+		return status;
+
+	save_autoneg = hw->phy.autoneg_advertised;
+
+	/* Setup link at least common link speed */
+	status = hw->mac.ops.setup_link(hw, lcd_speed, false);
+
+	/* restore autoneg from before setting lplu speed */
+	hw->phy.autoneg_advertised = save_autoneg;
+
+	return status;
+}
+
 /** ixgbe_init_phy_ops_X550em - PHY/SFP specific init
  *  @hw: pointer to hardware structure
  *
@@ -1528,6 +1666,11 @@ static s32 ixgbe_init_phy_ops_X550em(struct ixgbe_hw *hw)
 			ret_val = ixgbe_setup_kr_speed_x550em(hw, speed);
 		}
 
+		/* setup SW LPLU only for first revision */
+		if (!(IXGBE_FUSES0_REV1 & IXGBE_READ_REG(hw,
+							IXGBE_FUSES0_GROUP(0))))
+			phy->ops.enter_lplu = ixgbe_enter_lplu_t_x550em;
+
 		phy->ops.handle_lasi = ixgbe_handle_lasi_ext_t_x550em;
 		phy->ops.reset = ixgbe_reset_phy_t_X550em;
 		break;