ixgbe: Add X550EM_x dual-speed SFP+ support

This patch adds X550EM_x SFP+ dual-speed support. 82599 fiber link
code was moved from ixgbe_82599.c to ixgbe_common.c for use by
X550EM. SFP MAC link code is added to x550EM.

Signed-off-by: Mark Rustad <mark.d.rustad@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_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
index 3f56a80..2cd0c3a 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
@@ -3920,3 +3920,213 @@
 	fwsm &= IXGBE_FWSM_MODE_MASK;
 	return fwsm == IXGBE_FWSM_FW_MODE_PT;
 }
+
+/**
+ *  ixgbe_setup_mac_link_multispeed_fiber - Set MAC link speed
+ *  @hw: pointer to hardware structure
+ *  @speed: new link speed
+ *  @autoneg_wait_to_complete: true when waiting for completion is needed
+ *
+ *  Set the link speed in the MAC and/or PHY register and restarts link.
+ */
+s32 ixgbe_setup_mac_link_multispeed_fiber(struct ixgbe_hw *hw,
+					  ixgbe_link_speed speed,
+					  bool autoneg_wait_to_complete)
+{
+	ixgbe_link_speed link_speed = IXGBE_LINK_SPEED_UNKNOWN;
+	ixgbe_link_speed highest_link_speed = IXGBE_LINK_SPEED_UNKNOWN;
+	s32 status = 0;
+	u32 speedcnt = 0;
+	u32 i = 0;
+	bool autoneg, link_up = false;
+
+	/* Mask off requested but non-supported speeds */
+	status = hw->mac.ops.get_link_capabilities(hw, &link_speed, &autoneg);
+	if (status)
+		return status;
+
+	speed &= link_speed;
+
+	/* Try each speed one by one, highest priority first.  We do this in
+	 * software because 10Gb fiber doesn't support speed autonegotiation.
+	 */
+	if (speed & IXGBE_LINK_SPEED_10GB_FULL) {
+		speedcnt++;
+		highest_link_speed = IXGBE_LINK_SPEED_10GB_FULL;
+
+		/* If we already have link at this speed, just jump out */
+		status = hw->mac.ops.check_link(hw, &link_speed, &link_up,
+						false);
+		if (status)
+			return status;
+
+		if (link_speed == IXGBE_LINK_SPEED_10GB_FULL && link_up)
+			goto out;
+
+		/* Set the module link speed */
+		switch (hw->phy.media_type) {
+		case ixgbe_media_type_fiber:
+			hw->mac.ops.set_rate_select_speed(hw,
+						    IXGBE_LINK_SPEED_10GB_FULL);
+			break;
+		case ixgbe_media_type_fiber_qsfp:
+			/* QSFP module automatically detects MAC link speed */
+			break;
+		default:
+			hw_dbg(hw, "Unexpected media type\n");
+			break;
+		}
+
+		/* Allow module to change analog characteristics (1G->10G) */
+		msleep(40);
+
+		status = hw->mac.ops.setup_mac_link(hw,
+						    IXGBE_LINK_SPEED_10GB_FULL,
+						    autoneg_wait_to_complete);
+		if (status)
+			return status;
+
+		/* Flap the Tx laser if it has not already been done */
+		if (hw->mac.ops.flap_tx_laser)
+			hw->mac.ops.flap_tx_laser(hw);
+
+		/* Wait for the controller to acquire link.  Per IEEE 802.3ap,
+		 * Section 73.10.2, we may have to wait up to 500ms if KR is
+		 * attempted.  82599 uses the same timing for 10g SFI.
+		 */
+		for (i = 0; i < 5; i++) {
+			/* Wait for the link partner to also set speed */
+			msleep(100);
+
+			/* If we have link, just jump out */
+			status = hw->mac.ops.check_link(hw, &link_speed,
+							&link_up, false);
+			if (status)
+				return status;
+
+			if (link_up)
+				goto out;
+		}
+	}
+
+	if (speed & IXGBE_LINK_SPEED_1GB_FULL) {
+		speedcnt++;
+		if (highest_link_speed == IXGBE_LINK_SPEED_UNKNOWN)
+			highest_link_speed = IXGBE_LINK_SPEED_1GB_FULL;
+
+		/* If we already have link at this speed, just jump out */
+		status = hw->mac.ops.check_link(hw, &link_speed, &link_up,
+						false);
+		if (status)
+			return status;
+
+		if (link_speed == IXGBE_LINK_SPEED_1GB_FULL && link_up)
+			goto out;
+
+		/* Set the module link speed */
+		switch (hw->phy.media_type) {
+		case ixgbe_media_type_fiber:
+			hw->mac.ops.set_rate_select_speed(hw,
+						     IXGBE_LINK_SPEED_1GB_FULL);
+			break;
+		case ixgbe_media_type_fiber_qsfp:
+			/* QSFP module automatically detects link speed */
+			break;
+		default:
+			hw_dbg(hw, "Unexpected media type\n");
+			break;
+		}
+
+		/* Allow module to change analog characteristics (10G->1G) */
+		msleep(40);
+
+		status = hw->mac.ops.setup_mac_link(hw,
+						    IXGBE_LINK_SPEED_1GB_FULL,
+						    autoneg_wait_to_complete);
+		if (status)
+			return status;
+
+		/* Flap the Tx laser if it has not already been done */
+		if (hw->mac.ops.flap_tx_laser)
+			hw->mac.ops.flap_tx_laser(hw);
+
+		/* Wait for the link partner to also set speed */
+		msleep(100);
+
+		/* If we have link, just jump out */
+		status = hw->mac.ops.check_link(hw, &link_speed, &link_up,
+						false);
+		if (status)
+			return status;
+
+		if (link_up)
+			goto out;
+	}
+
+	/* We didn't get link.  Configure back to the highest speed we tried,
+	 * (if there was more than one).  We call ourselves back with just the
+	 * single highest speed that the user requested.
+	 */
+	if (speedcnt > 1)
+		status = ixgbe_setup_mac_link_multispeed_fiber(hw,
+						      highest_link_speed,
+						      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;
+}
+
+/**
+ *  ixgbe_set_soft_rate_select_speed - Set module link speed
+ *  @hw: pointer to hardware structure
+ *  @speed: link speed to set
+ *
+ *  Set module link speed via the soft rate select.
+ */
+void ixgbe_set_soft_rate_select_speed(struct ixgbe_hw *hw,
+				      ixgbe_link_speed speed)
+{
+	s32 status;
+	u8 rs, eeprom_data;
+
+	switch (speed) {
+	case IXGBE_LINK_SPEED_10GB_FULL:
+		/* one bit mask same as setting on */
+		rs = IXGBE_SFF_SOFT_RS_SELECT_10G;
+		break;
+	case IXGBE_LINK_SPEED_1GB_FULL:
+		rs = IXGBE_SFF_SOFT_RS_SELECT_1G;
+		break;
+	default:
+		hw_dbg(hw, "Invalid fixed module speed\n");
+		return;
+	}
+
+	/* Set RS0 */
+	status = hw->phy.ops.read_i2c_byte(hw, IXGBE_SFF_SFF_8472_OSCB,
+					   IXGBE_I2C_EEPROM_DEV_ADDR2,
+					   &eeprom_data);
+	if (status) {
+		hw_dbg(hw, "Failed to read Rx Rate Select RS0\n");
+		return;
+	}
+
+	eeprom_data = (eeprom_data & ~IXGBE_SFF_SOFT_RS_SELECT_MASK) | rs;
+
+	status = hw->phy.ops.write_i2c_byte(hw, IXGBE_SFF_SFF_8472_OSCB,
+					    IXGBE_I2C_EEPROM_DEV_ADDR2,
+					    eeprom_data);
+	if (status) {
+		hw_dbg(hw, "Failed to write Rx Rate Select RS0\n");
+		return;
+	}
+}