ixgbe: Fix backplane flow control autoneg

Backplane flow control autonegotiation is currently broken for
ixgbe devices.  This patch fixes the flow control issues
with clause 37 autoneg.
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ixgbe/ixgbe_82598.c

@@ -425,7 +425,7 @@ static s32 ixgbe_fc_enable_82598(struct ixgbe_hw *hw, s32 packetbuf_num)
 #endif /* CONFIG_DCB */
 	default:
 		hw_dbg(hw, "Flow control param set incorrectly\n");
-		ret_val = -IXGBE_ERR_CONFIG;
+		ret_val = IXGBE_ERR_CONFIG;
 		goto out;
 		break;
 	}

drivers/net/ixgbe/ixgbe_type.h

@@ -1336,6 +1336,8 @@
 #define IXGBE_AUTOC_KX4_SUPP    0x80000000
 #define IXGBE_AUTOC_KX_SUPP     0x40000000
 #define IXGBE_AUTOC_PAUSE       0x30000000
+#define IXGBE_AUTOC_ASM_PAUSE   0x20000000
+#define IXGBE_AUTOC_SYM_PAUSE   0x10000000
 #define IXGBE_AUTOC_RF          0x08000000
 #define IXGBE_AUTOC_PD_TMR      0x06000000
 #define IXGBE_AUTOC_AN_RX_LOOSE 0x01000000
@@ -1404,6 +1406,8 @@
 #define IXGBE_LINK_UP_TIME      90 /* 9.0 Seconds */
 #define IXGBE_AUTO_NEG_TIME     45 /* 4.5 Seconds */
 
+#define IXGBE_LINKS2_AN_SUPPORTED   0x00000040
+
 /* PCS1GLSTA Bit Masks */
 #define IXGBE_PCS1GLSTA_LINK_OK         1
 #define IXGBE_PCS1GLSTA_SYNK_OK         0x10
@@ -1424,6 +1428,11 @@
 #define IXGBE_PCS1GLCTL_AN_ENABLE       0x10000
 #define IXGBE_PCS1GLCTL_AN_RESTART      0x20000
 
+/* ANLP1 Bit Masks */
+#define IXGBE_ANLP1_PAUSE               0x0C00
+#define IXGBE_ANLP1_SYM_PAUSE           0x0400
+#define IXGBE_ANLP1_ASM_PAUSE           0x0800
+
 /* SW Semaphore Register bitmasks */
 #define IXGBE_SWSM_SMBI 0x00000001 /* Driver Semaphore bit */
 #define IXGBE_SWSM_SWESMBI 0x00000002 /* FW Semaphore bit */