e1000: Only set IDE for tx when we are using TIDV/TADV

Spec fix: don't set IDE unless we are actually setting the tx
int delay time.

Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>

drivers/net/e1000/e1000_main.c

@@ -1580,8 +1580,11 @@ e1000_configure_tx(struct e1000_adapter *adapter)
 	e1000_config_collision_dist(hw);
 
 	/* Setup Transmit Descriptor Settings for eop descriptor */
-	adapter->txd_cmd = E1000_TXD_CMD_IDE | E1000_TXD_CMD_EOP |
-		E1000_TXD_CMD_IFCS;
+	adapter->txd_cmd = E1000_TXD_CMD_EOP | E1000_TXD_CMD_IFCS;
+
+	/* only set IDE if we are delaying interrupts using the timers */
+	if (adapter->tx_int_delay)
+		adapter->txd_cmd |= E1000_TXD_CMD_IDE;
 
 	if (hw->mac_type < e1000_82543)
 		adapter->txd_cmd |= E1000_TXD_CMD_RPS;