tg3: Preserve register settings for DASH

Broadcom's DASH (Desktop and mobile Architecture for System Hardware)
implementation requires that the driver preserve particular register
settings.  If the driver does not preserve them, communication with
the DASH firmware will be lost.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index 13640f1..0ebf2ff 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -2126,6 +2126,13 @@
 		     (tp->tg3_flags & TG3_FLAG_WOL_ENABLE))
 			mac_mode |= MAC_MODE_MAGIC_PKT_ENABLE;
 
+		if (tp->tg3_flags3 & TG3_FLG3_ENABLE_APE) {
+			mac_mode |= tp->mac_mode &
+				    (MAC_MODE_APE_TX_EN | MAC_MODE_APE_RX_EN);
+			if (mac_mode & MAC_MODE_APE_TX_EN)
+				mac_mode |= MAC_MODE_TDE_ENABLE;
+		}
+
 		tw32_f(MAC_MODE, mac_mode);
 		udelay(100);
 
@@ -5912,6 +5919,11 @@
 	} else if (tp->tg3_flags2 & TG3_FLG2_MII_SERDES) {
 		tp->mac_mode = MAC_MODE_PORT_MODE_GMII;
 		tw32_f(MAC_MODE, tp->mac_mode);
+	} else if (tp->tg3_flags3 & TG3_FLG3_ENABLE_APE) {
+		tp->mac_mode &= (MAC_MODE_APE_TX_EN | MAC_MODE_APE_RX_EN);
+		if (tp->mac_mode & MAC_MODE_APE_TX_EN)
+			tp->mac_mode |= MAC_MODE_TDE_ENABLE;
+		tw32_f(MAC_MODE, tp->mac_mode);
 	} else
 		tw32_f(MAC_MODE, 0);
 	udelay(40);
@@ -7412,7 +7424,11 @@
 		udelay(10);
 	}
 
-	tp->mac_mode = MAC_MODE_TXSTAT_ENABLE | MAC_MODE_RXSTAT_ENABLE |
+	if (tp->tg3_flags3 & TG3_FLG3_ENABLE_APE)
+		tp->mac_mode &= MAC_MODE_APE_TX_EN | MAC_MODE_APE_RX_EN;
+	else
+		tp->mac_mode = 0;
+	tp->mac_mode |= MAC_MODE_TXSTAT_ENABLE | MAC_MODE_RXSTAT_ENABLE |
 		MAC_MODE_TDE_ENABLE | MAC_MODE_RDE_ENABLE | MAC_MODE_FHDE_ENABLE;
 	if (!(tp->tg3_flags2 & TG3_FLG2_5705_PLUS) &&
 	    !(tp->tg3_flags2 & TG3_FLG2_PHY_SERDES) &&
@@ -12422,6 +12438,13 @@
 				       tp->misc_host_ctrl);
 	}
 
+	/* Preserve the APE MAC_MODE bits */
+	if (tp->tg3_flags3 & TG3_FLG3_ENABLE_APE)
+		tp->mac_mode = tr32(MAC_MODE) |
+			       MAC_MODE_APE_TX_EN | MAC_MODE_APE_RX_EN;
+	else
+		tp->mac_mode = TG3_DEF_MAC_MODE;
+
 	/* these are limited to 10/100 only */
 	if ((GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5703 &&
 	     (grc_misc_cfg == 0x8000 || grc_misc_cfg == 0x4000)) ||
@@ -13281,7 +13304,6 @@
 	tp->pdev = pdev;
 	tp->dev = dev;
 	tp->pm_cap = pm_cap;
-	tp->mac_mode = TG3_DEF_MAC_MODE;
 	tp->rx_mode = TG3_DEF_RX_MODE;
 	tp->tx_mode = TG3_DEF_TX_MODE;