ixgbe: Disable flow control for XFI

Flow control autonegotiation is not supported for XFI.  Make sure that
ixgbe_device_supports_autoneg_fc() returns false and
hw->fc.disable_fc_autoneg is set to true to avoid running the fc_autoneg
function for that device.
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_common.c

@@ -97,6 +97,9 @@ bool ixgbe_device_supports_autoneg_fc(struct ixgbe_hw *hw)
 
 		break;
 	case ixgbe_media_type_backplane:
+		if (hw->device_id == IXGBE_DEV_ID_X550EM_X_XFI)
+			supported = false;
+		else
 			supported = true;
 		break;
 	case ixgbe_media_type_copper:

drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c

@@ -2843,7 +2843,7 @@ static s32 ixgbe_setup_fc_x550em(struct ixgbe_hw *hw)
 {
 	bool pause, asm_dir;
 	u32 reg_val;
-	s32 rc;
+	s32 rc = 0;
 
 	/* Validate the requested mode */
 	if (hw->fc.strict_ieee && hw->fc.requested_mode == ixgbe_fc_rx_pause) {
@@ -2886,11 +2886,10 @@ static s32 ixgbe_setup_fc_x550em(struct ixgbe_hw *hw)
 		return IXGBE_ERR_CONFIG;
 	}
 
-	if (hw->device_id != IXGBE_DEV_ID_X550EM_X_KR &&
-	    hw->device_id != IXGBE_DEV_ID_X550EM_A_KR &&
-	    hw->device_id != IXGBE_DEV_ID_X550EM_A_KR_L)
-		return 0;
-
+	switch (hw->device_id) {
+	case IXGBE_DEV_ID_X550EM_X_KR:
+	case IXGBE_DEV_ID_X550EM_A_KR:
+	case IXGBE_DEV_ID_X550EM_A_KR_L:
 		rc = hw->mac.ops.read_iosf_sb_reg(hw,
 					    IXGBE_KRM_AN_CNTL_1(hw->bus.lan_id),
 					    IXGBE_SB_IOSF_TARGET_KR_PHY,
@@ -2911,7 +2910,13 @@ static s32 ixgbe_setup_fc_x550em(struct ixgbe_hw *hw)
 
 		/* This device does not fully support AN. */
 		hw->fc.disable_fc_autoneg = true;
-
+		break;
+	case IXGBE_DEV_ID_X550EM_X_XFI:
+		hw->fc.disable_fc_autoneg = true;
+		break;
+	default:
+		break;
+	}
 	return rc;
 }