tg3: Fix loopback tests

The half-duplex bit in the MAC MODE register will be set during the
loopback test if the external link is in half-duplex mode.  This will
cause the loopback test to fail on newer devices.  This patch turns the
half-duplex bit off for the test.

Also, newer devices fail the internal phy loopback test because the phy
link takes a little while to come up.  This patch adds code to wait for
the link before proceeding with the test.

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

@@ -10845,8 +10845,9 @@ static int tg3_run_loopback(struct tg3 *tp, int loopback_mode)
 		if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5780)
 			return 0;
 
-		mac_mode = (tp->mac_mode & ~MAC_MODE_PORT_MODE_MASK) |
-			   MAC_MODE_PORT_INT_LPBACK;
+		mac_mode = tp->mac_mode &
+			   ~(MAC_MODE_PORT_MODE_MASK | MAC_MODE_HALF_DUPLEX);
+		mac_mode |= MAC_MODE_PORT_INT_LPBACK;
 		if (!(tp->tg3_flags2 & TG3_FLG2_5705_PLUS))
 			mac_mode |= MAC_MODE_LINK_POLARITY;
 		if (tp->phy_flags & TG3_PHYFLG_10_100_ONLY)
@@ -10868,7 +10869,8 @@ static int tg3_run_loopback(struct tg3 *tp, int loopback_mode)
 		tg3_writephy(tp, MII_BMCR, val);
 		udelay(40);
 
-		mac_mode = tp->mac_mode & ~MAC_MODE_PORT_MODE_MASK;
+		mac_mode = tp->mac_mode &
+			   ~(MAC_MODE_PORT_MODE_MASK | MAC_MODE_HALF_DUPLEX);
 		if (tp->phy_flags & TG3_PHYFLG_IS_FET) {
 			tg3_writephy(tp, MII_TG3_FET_PTEST,
 				     MII_TG3_FET_PTEST_FRC_TX_LINK |
@@ -10896,6 +10898,13 @@ static int tg3_run_loopback(struct tg3 *tp, int loopback_mode)
 				     MII_TG3_EXT_CTRL_LNK3_LED_MODE);
 		}
 		tw32(MAC_MODE, mac_mode);
+
+		/* Wait for link */
+		for (i = 0; i < 100; i++) {
+			if (tr32(MAC_TX_STATUS) & TX_STATUS_LINK_UP)
+				break;
+			mdelay(1);
+		}
 	} else {
 		return -EINVAL;
 	}