tg3: Prevent spurious tx timeout by setting carrier off before tx disable.

The watchdog will not trigger when the carrier is off when reconfiguring
the device.  Because carrier state is now off during reset, we need to
introduce a link_up flag to keep track of link state during PHY setup.

Signed-off-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/tg3.c

@@ -2473,6 +2473,18 @@ static int tg3_phy_reset_5703_4_5(struct tg3 *tp)
 	return err;
 }
 
+static void tg3_carrier_on(struct tg3 *tp)
+{
+	netif_carrier_on(tp->dev);
+	tp->link_up = true;
+}
+
+static void tg3_carrier_off(struct tg3 *tp)
+{
+	netif_carrier_off(tp->dev);
+	tp->link_up = false;
+}
+
 /* This will reset the tigon3 PHY if there is no valid
  * link unless the FORCE argument is non-zero.
  */
@@ -2491,8 +2503,8 @@ static int tg3_phy_reset(struct tg3 *tp)
 	if (err != 0)
 		return -EBUSY;
 
-	if (netif_running(tp->dev) && netif_carrier_ok(tp->dev)) {
-		netif_carrier_off(tp->dev);
+	if (netif_running(tp->dev) && tp->link_up) {
+		tg3_carrier_off(tp);
 		tg3_link_report(tp);
 	}
 
@@ -4186,6 +4198,24 @@ static bool tg3_phy_copper_fetch_rmtadv(struct tg3 *tp, u32 *rmtadv)
 	return true;
 }
 
+static bool tg3_test_and_report_link_chg(struct tg3 *tp, int curr_link_up)
+{
+	if (curr_link_up != tp->link_up) {
+		if (curr_link_up) {
+			tg3_carrier_on(tp);
+		} else {
+			tg3_carrier_off(tp);
+			if (tp->phy_flags & TG3_PHYFLG_MII_SERDES)
+				tp->phy_flags &= ~TG3_PHYFLG_PARALLEL_DETECT;
+		}
+
+		tg3_link_report(tp);
+		return true;
+	}
+
+	return false;
+}
+
 static int tg3_setup_copper_phy(struct tg3 *tp, int force_reset)
 {
 	int current_link_up;
@@ -4218,7 +4248,7 @@ static int tg3_setup_copper_phy(struct tg3 *tp, int force_reset)
 	if ((GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5703 ||
 	     GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5704 ||
 	     GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5705) &&
-	    netif_carrier_ok(tp->dev)) {
+	    tp->link_up) {
 		tg3_readphy(tp, MII_BMSR, &bmsr);
 		if (!tg3_readphy(tp, MII_BMSR, &bmsr) &&
 		    !(bmsr & BMSR_LSTATUS))
@@ -4460,13 +4490,7 @@ relink:
 						 PCI_EXP_LNKCTL_CLKREQ_EN);
 	}
 
-	if (current_link_up != netif_carrier_ok(tp->dev)) {
-		if (current_link_up)
-			netif_carrier_on(tp->dev);
-		else
-			netif_carrier_off(tp->dev);
-		tg3_link_report(tp);
-	}
+	tg3_test_and_report_link_chg(tp, current_link_up);
 
 	return 0;
 }
@@ -5106,7 +5130,7 @@ static int tg3_setup_fiber_phy(struct tg3 *tp, int force_reset)
 	orig_active_duplex = tp->link_config.active_duplex;
 
 	if (!tg3_flag(tp, HW_AUTONEG) &&
-	    netif_carrier_ok(tp->dev) &&
+	    tp->link_up &&
 	    tg3_flag(tp, INIT_COMPLETE)) {
 		mac_status = tr32(MAC_STATUS);
 		mac_status &= (MAC_STATUS_PCS_SYNCED |
@@ -5184,13 +5208,7 @@ static int tg3_setup_fiber_phy(struct tg3 *tp, int force_reset)
 				    LED_CTRL_TRAFFIC_OVERRIDE));
 	}
 
-	if (current_link_up != netif_carrier_ok(tp->dev)) {
-		if (current_link_up)
-			netif_carrier_on(tp->dev);
-		else
-			netif_carrier_off(tp->dev);
-		tg3_link_report(tp);
-	} else {
+	if (!tg3_test_and_report_link_chg(tp, current_link_up)) {
 		u32 now_pause_cfg = tp->link_config.active_flowctrl;
 		if (orig_pause_cfg != now_pause_cfg ||
 		    orig_active_speed != tp->link_config.active_speed ||
@@ -5283,7 +5301,7 @@ static int tg3_setup_fiber_mii_phy(struct tg3 *tp, int force_reset)
 			new_bmcr |= BMCR_SPEED1000;
 
 			/* Force a linkdown */
-			if (netif_carrier_ok(tp->dev)) {
+			if (tp->link_up) {
 				u32 adv;
 
 				err |= tg3_readphy(tp, MII_ADVERTISE, &adv);
@@ -5295,7 +5313,7 @@ static int tg3_setup_fiber_mii_phy(struct tg3 *tp, int force_reset)
 							   BMCR_ANRESTART |
 							   BMCR_ANENABLE);
 				udelay(10);
-				netif_carrier_off(tp->dev);
+				tg3_carrier_off(tp);
 			}
 			tg3_writephy(tp, MII_BMCR, new_bmcr);
 			bmcr = new_bmcr;
@@ -5361,15 +5379,7 @@ static int tg3_setup_fiber_mii_phy(struct tg3 *tp, int force_reset)
 	tp->link_config.active_speed = current_speed;
 	tp->link_config.active_duplex = current_duplex;
 
-	if (current_link_up != netif_carrier_ok(tp->dev)) {
-		if (current_link_up)
-			netif_carrier_on(tp->dev);
-		else {
-			netif_carrier_off(tp->dev);
-			tp->phy_flags &= ~TG3_PHYFLG_PARALLEL_DETECT;
-		}
-		tg3_link_report(tp);
-	}
+	tg3_test_and_report_link_chg(tp, current_link_up);
 	return err;
 }
 
@@ -5381,7 +5391,7 @@ static void tg3_serdes_parallel_detect(struct tg3 *tp)
 		return;
 	}
 
-	if (!netif_carrier_ok(tp->dev) &&
+	if (!tp->link_up &&
 	    (tp->link_config.autoneg == AUTONEG_ENABLE)) {
 		u32 bmcr;
 
@@ -5411,7 +5421,7 @@ static void tg3_serdes_parallel_detect(struct tg3 *tp)
 				tp->phy_flags |= TG3_PHYFLG_PARALLEL_DETECT;
 			}
 		}
-	} else if (netif_carrier_ok(tp->dev) &&
+	} else if (tp->link_up &&
 		   (tp->link_config.autoneg == AUTONEG_ENABLE) &&
 		   (tp->phy_flags & TG3_PHYFLG_PARALLEL_DETECT)) {
 		u32 phy2;
@@ -5477,7 +5487,7 @@ static int tg3_setup_phy(struct tg3 *tp, int force_reset)
 		     (32 << TX_LENGTHS_SLOT_TIME_SHIFT));
 
 	if (!tg3_flag(tp, 5705_PLUS)) {
-		if (netif_carrier_ok(tp->dev)) {
+		if (tp->link_up) {
 			tw32(HOSTCC_STAT_COAL_TICKS,
 			     tp->coal.stats_block_coalesce_usecs);
 		} else {
@@ -5487,7 +5497,7 @@ static int tg3_setup_phy(struct tg3 *tp, int force_reset)
 
 	if (tg3_flag(tp, ASPM_WORKAROUND)) {
 		val = tr32(PCIE_PWR_MGMT_THRESH);
-		if (!netif_carrier_ok(tp->dev))
+		if (!tp->link_up)
 			val = (val & ~PCIE_PWR_MGMT_L1_THRESH_MSK) |
 			      tp->pwrmgmt_thresh;
 		else
@@ -6503,6 +6513,7 @@ static inline void tg3_netif_stop(struct tg3 *tp)
 {
 	tp->dev->trans_start = jiffies;	/* prevent tx timeout */
 	tg3_napi_disable(tp);
+	netif_carrier_off(tp->dev);
 	netif_tx_disable(tp->dev);
 }
 
@@ -6514,6 +6525,9 @@ static inline void tg3_netif_start(struct tg3 *tp)
 	 */
 	netif_tx_wake_all_queues(tp->dev);
 
+	if (tp->link_up)
+		netif_carrier_on(tp->dev);
+
 	tg3_napi_enable(tp);
 	tp->napi[0].hw_status->status |= SD_STATUS_UPDATED;
 	tg3_enable_ints(tp);
@@ -8412,7 +8426,7 @@ static void __tg3_set_coalesce(struct tg3 *tp, struct ethtool_coalesce *ec)
 		tw32(HOSTCC_RXCOAL_TICK_INT, ec->rx_coalesce_usecs_irq);
 		tw32(HOSTCC_TXCOAL_TICK_INT, ec->tx_coalesce_usecs_irq);
 
-		if (!netif_carrier_ok(tp->dev))
+		if (!tp->link_up)
 			val = 0;
 
 		tw32(HOSTCC_STAT_COAL_TICKS, val);
@@ -9705,7 +9719,7 @@ static void tg3_periodic_fetch_stats(struct tg3 *tp)
 {
 	struct tg3_hw_stats *sp = tp->hw_stats;
 
-	if (!netif_carrier_ok(tp->dev))
+	if (!tp->link_up)
 		return;
 
 	TG3_STAT_ADD32(&sp->tx_octets, MAC_TX_STATS_OCTETS);
@@ -9849,11 +9863,11 @@ static void tg3_timer(unsigned long __opaque)
 			u32 mac_stat = tr32(MAC_STATUS);
 			int need_setup = 0;
 
-			if (netif_carrier_ok(tp->dev) &&
+			if (tp->link_up &&
 			    (mac_stat & MAC_STATUS_LNKSTATE_CHANGED)) {
 				need_setup = 1;
 			}
-			if (!netif_carrier_ok(tp->dev) &&
+			if (!tp->link_up &&
 			    (mac_stat & (MAC_STATUS_PCS_SYNCED |
 					 MAC_STATUS_SIGNAL_DET))) {
 				need_setup = 1;
@@ -10505,7 +10519,7 @@ static int tg3_open(struct net_device *dev)
 		}
 	}
 
-	netif_carrier_off(tp->dev);
+	tg3_carrier_off(tp);
 
 	err = tg3_power_up(tp);
 	if (err)
@@ -10538,7 +10552,7 @@ static int tg3_close(struct net_device *dev)
 
 	tg3_power_down(tp);
 
-	netif_carrier_off(tp->dev);
+	tg3_carrier_off(tp);
 
 	return 0;
 }
@@ -10912,7 +10926,7 @@ static int tg3_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 			cmd->advertising |= ADVERTISED_Asym_Pause;
 		}
 	}
-	if (netif_running(dev) && netif_carrier_ok(dev)) {
+	if (netif_running(dev) && tp->link_up) {
 		ethtool_cmd_speed_set(cmd, tp->link_config.active_speed);
 		cmd->duplex = tp->link_config.active_duplex;
 		cmd->lp_advertising = tp->link_config.rmt_adv;
@@ -11430,7 +11444,7 @@ static int tg3_set_channels(struct net_device *dev,
 
 	tg3_stop(tp);
 
-	netif_carrier_off(dev);
+	tg3_carrier_off(tp);
 
 	tg3_start(tp, true, false);
 
@@ -11779,7 +11793,7 @@ static int tg3_test_link(struct tg3 *tp)
 		max = TG3_COPPER_TIMEOUT_SEC;
 
 	for (i = 0; i < max; i++) {
-		if (netif_carrier_ok(tp->dev))
+		if (tp->link_up)
 			return 0;
 
 		if (msleep_interruptible(1000))

drivers/net/ethernet/broadcom/tg3.h

@@ -3269,6 +3269,7 @@ struct tg3 {
 #if IS_ENABLED(CONFIG_HWMON)
 	struct device			*hwmon_dev;
 #endif
+	bool				link_up;
 };
 
 #endif /* !(_T3_H) */