tg3: Disable multivec mode for 1 MSIX vector

For single vector MSI-X allocations, we do not want to enable
multivector modes.  This patch makes the necessary corrections.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/tg3.c

@@ -8322,7 +8322,8 @@ static int tg3_reset_hw(struct tg3 *tp, int reset_phy)
 	tw32_f(GRC_LOCAL_CTRL, tp->grc_local_ctrl);
 	udelay(100);
 
-	if (tp->tg3_flags2 & TG3_FLG2_USING_MSIX) {
+	if ((tp->tg3_flags2 & TG3_FLG2_USING_MSIX) &&
+		tp->irq_cnt > 1) {
 		val = tr32(MSGINT_MODE);
 		val |= MSGINT_MODE_MULTIVEC_EN | MSGINT_MODE_ENABLE;
 		tw32(MSGINT_MODE, val);
@@ -9062,7 +9063,8 @@ static void tg3_ints_init(struct tg3 *tp)
 
 	if (tp->tg3_flags2 & TG3_FLG2_USING_MSI_OR_MSIX) {
 		u32 msi_mode = tr32(MSGINT_MODE);
-		if (tp->tg3_flags2 & TG3_FLG2_USING_MSIX)
+		if ((tp->tg3_flags2 & TG3_FLG2_USING_MSIX) &&
+		    tp->irq_cnt > 1)
 			msi_mode |= MSGINT_MODE_MULTIVEC_EN;
 		tw32(MSGINT_MODE, msi_mode | MSGINT_MODE_ENABLE);
 	}