1 files changed, 85 insertions, 16 deletions

diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c
index abe1eabc0171..a3a9392a4954 100644
--- a/drivers/net/ethernet/arc/emac_main.c
+++ b/drivers/net/ethernet/arc/emac_main.c
@@ -26,7 +26,6 @@
 
 #include "emac.h"
 
-
 /**
  * arc_emac_tx_avail - Return the number of available slots in the tx ring.
  * @priv: Pointer to ARC EMAC private data structure.
@@ -66,7 +65,7 @@ static void arc_emac_adjust_link(struct net_device *ndev)
 	if (priv->duplex != phy_dev->duplex) {
 		reg = arc_reg_get(priv, R_CTRL);
 
-		if (DUPLEX_FULL == phy_dev->duplex)
+		if (phy_dev->duplex == DUPLEX_FULL)
 			reg |= ENFL_MASK;
 		else
 			reg &= ~ENFL_MASK;
@@ -163,7 +162,7 @@ static void arc_emac_tx_clean(struct net_device *ndev)
 		struct sk_buff *skb = tx_buff->skb;
 		unsigned int info = le32_to_cpu(txbd->info);
 
-		if ((info & FOR_EMAC) || !txbd->data)
+		if ((info & FOR_EMAC) || !txbd->data || !skb)
 			break;
 
 		if (unlikely(info & (DROP | DEFR | LTCL | UFLO))) {
@@ -191,6 +190,7 @@ static void arc_emac_tx_clean(struct net_device *ndev)
 
 		txbd->data = 0;
 		txbd->info = 0;
+		tx_buff->skb = NULL;
 
 		*txbd_dirty = (*txbd_dirty + 1) % TX_BD_NUM;
 	}
@@ -446,6 +446,9 @@ static int arc_emac_open(struct net_device *ndev)
 		*last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM;
 	}
 
+	priv->txbd_curr = 0;
+	priv->txbd_dirty = 0;
+
 	/* Clean Tx BD's */
 	memset(priv->txbd, 0, TX_RING_SZ);
 
@@ -462,9 +465,9 @@ static int arc_emac_open(struct net_device *ndev)
 
 	/* Set CONTROL */
 	arc_reg_set(priv, R_CTRL,
-		     (RX_BD_NUM << 24) |	/* RX BD table length */
-		     (TX_BD_NUM << 16) |	/* TX BD table length */
-		     TXRN_MASK | RXRN_MASK);
+		    (RX_BD_NUM << 24) |	/* RX BD table length */
+		    (TX_BD_NUM << 16) |	/* TX BD table length */
+		    TXRN_MASK | RXRN_MASK);
 
 	napi_enable(&priv->napi);
 
@@ -514,6 +517,68 @@ static void arc_emac_set_rx_mode(struct net_device *ndev)
 }
 
 /**
+ * arc_free_tx_queue - free skb from tx queue
+ * @ndev:	Pointer to the network device.
+ *
+ * This function must be called while EMAC disable
+ */
+static void arc_free_tx_queue(struct net_device *ndev)
+{
+	struct arc_emac_priv *priv = netdev_priv(ndev);
+	unsigned int i;
+
+	for (i = 0; i < TX_BD_NUM; i++) {
+		struct arc_emac_bd *txbd = &priv->txbd[i];
+		struct buffer_state *tx_buff = &priv->tx_buff[i];
+
+		if (tx_buff->skb) {
+			dma_unmap_single(&ndev->dev,
+					 dma_unmap_addr(tx_buff, addr),
+					 dma_unmap_len(tx_buff, len),
+					 DMA_TO_DEVICE);
+
+			/* return the sk_buff to system */
+			dev_kfree_skb_irq(tx_buff->skb);
+		}
+
+		txbd->info = 0;
+		txbd->data = 0;
+		tx_buff->skb = NULL;
+	}
+}
+
+/**
+ * arc_free_rx_queue - free skb from rx queue
+ * @ndev:	Pointer to the network device.
+ *
+ * This function must be called while EMAC disable
+ */
+static void arc_free_rx_queue(struct net_device *ndev)
+{
+	struct arc_emac_priv *priv = netdev_priv(ndev);
+	unsigned int i;
+
+	for (i = 0; i < RX_BD_NUM; i++) {
+		struct arc_emac_bd *rxbd = &priv->rxbd[i];
+		struct buffer_state *rx_buff = &priv->rx_buff[i];
+
+		if (rx_buff->skb) {
+			dma_unmap_single(&ndev->dev,
+					 dma_unmap_addr(rx_buff, addr),
+					 dma_unmap_len(rx_buff, len),
+					 DMA_FROM_DEVICE);
+
+			/* return the sk_buff to system */
+			dev_kfree_skb_irq(rx_buff->skb);
+		}
+
+		rxbd->info = 0;
+		rxbd->data = 0;
+		rx_buff->skb = NULL;
+	}
+}
+
+/**
  * arc_emac_stop - Close the network device.
  * @ndev:	Pointer to the network device.
  *
@@ -534,6 +599,10 @@ static int arc_emac_stop(struct net_device *ndev)
 	/* Disable EMAC */
 	arc_reg_clr(priv, R_CTRL, EN_MASK);
 
+	/* Return the sk_buff to system */
+	arc_free_tx_queue(ndev);
+	arc_free_rx_queue(ndev);
+
 	return 0;
 }
 
@@ -610,7 +679,6 @@ static int arc_emac_tx(struct sk_buff *skb, struct net_device *ndev)
 	dma_unmap_addr_set(&priv->tx_buff[*txbd_curr], addr, addr);
 	dma_unmap_len_set(&priv->tx_buff[*txbd_curr], len, len);
 
-	priv->tx_buff[*txbd_curr].skb = skb;
 	priv->txbd[*txbd_curr].data = cpu_to_le32(addr);
 
 	/* Make sure pointer to data buffer is set */
@@ -620,6 +688,11 @@ static int arc_emac_tx(struct sk_buff *skb, struct net_device *ndev)
 
 	*info = cpu_to_le32(FOR_EMAC | FIRST_OR_LAST_MASK | len);
 
+	/* Make sure info word is set */
+	wmb();
+
+	priv->tx_buff[*txbd_curr].skb = skb;
+
 	/* Increment index to point to the next BD */
 	*txbd_curr = (*txbd_curr + 1) % TX_BD_NUM;
 
@@ -647,8 +720,8 @@ static void arc_emac_set_address_internal(struct net_device *ndev)
 	struct arc_emac_priv *priv = netdev_priv(ndev);
 	unsigned int addr_low, addr_hi;
 
-	addr_low = le32_to_cpu(*(__le32 *) &ndev->dev_addr[0]);
-	addr_hi = le16_to_cpu(*(__le16 *) &ndev->dev_addr[4]);
+	addr_low = le32_to_cpu(*(__le32 *)&ndev->dev_addr[0]);
+	addr_hi = le16_to_cpu(*(__le16 *)&ndev->dev_addr[4]);
 
 	arc_reg_set(priv, R_ADDRL, addr_low);
 	arc_reg_set(priv, R_ADDRH, addr_hi);
@@ -704,7 +777,6 @@ int arc_emac_probe(struct net_device *ndev, int interface)
 	unsigned int id, clock_frequency, irq;
 	int err;
 
-
 	/* Get PHY from device tree */
 	phy_node = of_parse_phandle(dev->of_node, "phy", 0);
 	if (!phy_node) {
@@ -726,7 +798,6 @@ int arc_emac_probe(struct net_device *ndev, int interface)
 		return -ENODEV;
 	}
 
-
 	ndev->netdev_ops = &arc_emac_netdev_ops;
 	ndev->ethtool_ops = &arc_emac_ethtool_ops;
 	ndev->watchdog_timeo = TX_TIMEOUT;
@@ -737,9 +808,9 @@ int arc_emac_probe(struct net_device *ndev, int interface)
 	priv->dev = dev;
 
 	priv->regs = devm_ioremap_resource(dev, &res_regs);
-	if (IS_ERR(priv->regs)) {
+	if (IS_ERR(priv->regs))
 		return PTR_ERR(priv->regs);
-	}
+
 	dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs);
 
 	if (priv->clk) {
@@ -860,10 +931,8 @@ int arc_emac_remove(struct net_device *ndev)
 	unregister_netdev(ndev);
 	netif_napi_del(&priv->napi);
 
-	if (!IS_ERR(priv->clk)) {
+	if (!IS_ERR(priv->clk))
 		clk_disable_unprepare(priv->clk);
-	}
-
 
 	return 0;
 }