[BNX2]: Workaround hw interrupt bug

Add workaround for a hardware interrupt issue. When using INTA,
unmasking of the interrupt and the tag update should be done
separately to avoid some spurious interrupts,

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c
index ec08f83..7b99cf2 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -316,6 +316,10 @@
 	u32 val;
 
 	REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD,
+	       BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID |
+	       BNX2_PCICFG_INT_ACK_CMD_MASK_INT | bp->last_status_idx);
+
+	REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD,
 	       BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID | bp->last_status_idx);
 
 	val = REG_RD(bp, BNX2_HC_COMMAND);
@@ -1892,9 +1896,20 @@
 
 	if (!bnx2_has_work(bp)) {
 		netif_rx_complete(dev);
+		if (likely(bp->flags & USING_MSI_FLAG)) {
+			REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD,
+			       BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID |
+			       bp->last_status_idx);
+			return 0;
+		}
 		REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD,
-			BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID |
-			bp->last_status_idx);
+		       BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID |
+		       BNX2_PCICFG_INT_ACK_CMD_MASK_INT |
+		       bp->last_status_idx);
+
+		REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD,
+		       BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID |
+		       bp->last_status_idx);
 		return 0;
 	}