1 files changed, 76 insertions, 61 deletions

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index 6625012d734e..20fc7c8d1a50 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -85,7 +85,7 @@ struct ftgmac100 {
 	bool use_ncsi;
 
 	/* Misc */
-	int int_mask_all;
+	bool need_mac_restart;
 };
 
 static int ftgmac100_alloc_rx_page(struct ftgmac100 *priv,
@@ -1048,10 +1048,49 @@ static irqreturn_t ftgmac100_interrupt(int irq, void *dev_id)
 {
 	struct net_device *netdev = dev_id;
 	struct ftgmac100 *priv = netdev_priv(netdev);
+	unsigned int status, new_mask = FTGMAC100_INT_BAD;
 
-	/* Disable interrupts for polling */
-	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
-	napi_schedule(&priv->napi);
+	/* Fetch and clear interrupt bits, process abnormal ones */
+	status = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
+	iowrite32(status, priv->base + FTGMAC100_OFFSET_ISR);
+	if (unlikely(status & FTGMAC100_INT_BAD)) {
+
+		/* RX buffer unavailable */
+		if (status & FTGMAC100_INT_NO_RXBUF)
+			netdev->stats.rx_over_errors++;
+
+		/* received packet lost due to RX FIFO full */
+		if (status & FTGMAC100_INT_RPKT_LOST)
+			netdev->stats.rx_fifo_errors++;
+
+		/* sent packet lost due to excessive TX collision */
+		if (status & FTGMAC100_INT_XPKT_LOST)
+			netdev->stats.tx_fifo_errors++;
+
+		/* AHB error -> Reset the chip */
+		if (status & FTGMAC100_INT_AHB_ERR) {
+			if (net_ratelimit())
+				netdev_warn(netdev,
+					   "AHB bus error ! Resetting chip.\n");
+			iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
+			schedule_work(&priv->reset_task);
+			return IRQ_HANDLED;
+		}
+
+		/* We may need to restart the MAC after such errors, delay
+		 * this until after we have freed some Rx buffers though
+		 */
+		priv->need_mac_restart = true;
+
+		/* Disable those errors until we restart */
+		new_mask &= ~status;
+	}
+
+	/* Only enable "bad" interrupts while NAPI is on */
+	iowrite32(new_mask, priv->base + FTGMAC100_OFFSET_IER);
+
+	/* Schedule NAPI bh */
+	napi_schedule_irqoff(&priv->napi);
 
 	return IRQ_HANDLED;
 }
@@ -1059,68 +1098,51 @@ static irqreturn_t ftgmac100_interrupt(int irq, void *dev_id)
 static int ftgmac100_poll(struct napi_struct *napi, int budget)
 {
 	struct ftgmac100 *priv = container_of(napi, struct ftgmac100, napi);
-	struct net_device *netdev = priv->netdev;
-	unsigned int status;
-	bool completed = true;
+	bool more, completed = true;
 	int rx = 0;
 
-	status = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
-	iowrite32(status, priv->base + FTGMAC100_OFFSET_ISR);
-
-	if (status & (FTGMAC100_INT_RPKT_BUF | FTGMAC100_INT_NO_RXBUF)) {
-		/*
-		 * FTGMAC100_INT_RPKT_BUF:
-		 *	RX DMA has received packets into RX buffer successfully
-		 *
-		 * FTGMAC100_INT_NO_RXBUF:
-		 *	RX buffer unavailable
-		 */
-		bool retry;
+	ftgmac100_tx_complete(priv);
 
-		do {
-			retry = ftgmac100_rx_packet(priv, &rx);
-		} while (retry && rx < budget);
+	do {
+		more = ftgmac100_rx_packet(priv, &rx);
+	} while (more && rx < budget);
 
-		if (retry && rx == budget)
-			completed = false;
-	}
+	if (more && rx == budget)
+		completed = false;
 
-	if (status & (FTGMAC100_INT_XPKT_ETH | FTGMAC100_INT_XPKT_LOST)) {
-		/*
-		 * FTGMAC100_INT_XPKT_ETH:
-		 *	packet transmitted to ethernet successfully
-		 *
-		 * FTGMAC100_INT_XPKT_LOST:
-		 *	packet transmitted to ethernet lost due to late
-		 *	collision or excessive collision
-		 */
-		ftgmac100_tx_complete(priv);
-	}
-
-	if (status & priv->int_mask_all & (FTGMAC100_INT_NO_RXBUF |
-			FTGMAC100_INT_RPKT_LOST | FTGMAC100_INT_AHB_ERR)) {
-		if (net_ratelimit())
-			netdev_info(netdev, "[ISR] = 0x%x: %s%s%s\n", status,
-				    status & FTGMAC100_INT_NO_RXBUF ? "NO_RXBUF " : "",
-				    status & FTGMAC100_INT_RPKT_LOST ? "RPKT_LOST " : "",
-				    status & FTGMAC100_INT_AHB_ERR ? "AHB_ERR " : "");
 
-		if (status & FTGMAC100_INT_NO_RXBUF) {
-			/* RX buffer unavailable */
-			netdev->stats.rx_over_errors++;
-		}
+	/* The interrupt is telling us to kick the MAC back to life
+	 * after an RX overflow
+	 */
+	if (unlikely(priv->need_mac_restart)) {
+		ftgmac100_start_hw(priv);
 
-		if (status & FTGMAC100_INT_RPKT_LOST) {
-			/* received packet lost due to RX FIFO full */
-			netdev->stats.rx_fifo_errors++;
-		}
+		/* Re-enable "bad" interrupts */
+		iowrite32(FTGMAC100_INT_BAD,
+			  priv->base + FTGMAC100_OFFSET_IER);
 	}
 
+	/* Keep NAPI going if we have still packets to reclaim */
+	if (priv->tx_pending)
+		return budget;
+
 	if (completed) {
+		/* We are about to re-enable all interrupts. However
+		 * the HW has been latching RX/TX packet interrupts while
+		 * they were masked. So we clear them first, then we need
+		 * to re-check if there's something to process
+		 */
+		iowrite32(FTGMAC100_INT_RXTX,
+			  priv->base + FTGMAC100_OFFSET_ISR);
+		if (ftgmac100_rxdes_packet_ready
+		    (ftgmac100_current_rxdes(priv)) || priv->tx_pending)
+			return budget;
+
+		/* deschedule NAPI */
 		napi_complete(napi);
 
 		/* enable all interrupts */
-		iowrite32(priv->int_mask_all,
+		iowrite32(FTGMAC100_INT_ALL,
 			  priv->base + FTGMAC100_OFFSET_IER);
 	}
 
@@ -1148,7 +1170,7 @@ static int ftgmac100_init_all(struct ftgmac100 *priv, bool ignore_alloc_err)
 	netif_start_queue(priv->netdev);
 
 	/* Enable all interrupts */
-	iowrite32(priv->int_mask_all, priv->base + FTGMAC100_OFFSET_IER);
+	iowrite32(FTGMAC100_INT_ALL, priv->base + FTGMAC100_OFFSET_IER);
 
 	return err;
 }
@@ -1491,13 +1513,6 @@ static int ftgmac100_probe(struct platform_device *pdev)
 	/* MAC address from chip or random one */
 	ftgmac100_setup_mac(priv);
 
-	priv->int_mask_all = (FTGMAC100_INT_RPKT_LOST |
-			      FTGMAC100_INT_XPKT_ETH |
-			      FTGMAC100_INT_XPKT_LOST |
-			      FTGMAC100_INT_AHB_ERR |
-			      FTGMAC100_INT_RPKT_BUF |
-			      FTGMAC100_INT_NO_RXBUF);
-
 	if (of_machine_is_compatible("aspeed,ast2400") ||
 	    of_machine_is_compatible("aspeed,ast2500")) {
 		priv->rxdes0_edorr_mask = BIT(30);