Merge branch 'for-2.6.38' into for-2.6.39

1 files changed, 112 insertions, 48 deletions

diff --git a/drivers/net/ethoc.c b/drivers/net/ethoc.c
index c5a2fe099a8..b79d7e1555d 100644
--- a/drivers/net/ethoc.c
+++ b/drivers/net/ethoc.c
@@ -19,6 +19,7 @@
 #include <linux/platform_device.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 #include <net/ethoc.h>
 
 static int buffer_size = 0x8000; /* 32 KBytes */
@@ -184,7 +185,6 @@ MODULE_PARM_DESC(buffer_size, "DMA buffer allocation size");
  * @netdev:	pointer to network device structure
  * @napi:	NAPI structure
  * @msg_enable:	device state flags
- * @rx_lock:	receive lock
  * @lock:	device lock
  * @phy:	attached PHY
  * @mdio:	MDIO bus for PHY access
@@ -209,7 +209,6 @@ struct ethoc {
 	struct napi_struct napi;
 	u32 msg_enable;
 
-	spinlock_t rx_lock;
 	spinlock_t lock;
 
 	struct phy_device *phy;
@@ -413,10 +412,21 @@ static int ethoc_rx(struct net_device *dev, int limit)
 		unsigned int entry;
 		struct ethoc_bd bd;
 
-		entry = priv->num_tx + (priv->cur_rx % priv->num_rx);
+		entry = priv->num_tx + priv->cur_rx;
 		ethoc_read_bd(priv, entry, &bd);
-		if (bd.stat & RX_BD_EMPTY)
-			break;
+		if (bd.stat & RX_BD_EMPTY) {
+			ethoc_ack_irq(priv, INT_MASK_RX);
+			/* If packet (interrupt) came in between checking
+			 * BD_EMTPY and clearing the interrupt source, then we
+			 * risk missing the packet as the RX interrupt won't
+			 * trigger right away when we reenable it; hence, check
+			 * BD_EMTPY here again to make sure there isn't such a
+			 * packet waiting for us...
+			 */
+			ethoc_read_bd(priv, entry, &bd);
+			if (bd.stat & RX_BD_EMPTY)
+				break;
+		}
 
 		if (ethoc_update_rx_stats(priv, &bd) == 0) {
 			int size = bd.stat >> 16;
@@ -446,13 +456,14 @@ static int ethoc_rx(struct net_device *dev, int limit)
 		bd.stat &= ~RX_BD_STATS;
 		bd.stat |=  RX_BD_EMPTY;
 		ethoc_write_bd(priv, entry, &bd);
-		priv->cur_rx++;
+		if (++priv->cur_rx == priv->num_rx)
+			priv->cur_rx = 0;
 	}
 
 	return count;
 }
 
-static int ethoc_update_tx_stats(struct ethoc *dev, struct ethoc_bd *bd)
+static void ethoc_update_tx_stats(struct ethoc *dev, struct ethoc_bd *bd)
 {
 	struct net_device *netdev = dev->netdev;
 
@@ -482,32 +493,44 @@ static int ethoc_update_tx_stats(struct ethoc *dev, struct ethoc_bd *bd)
 	netdev->stats.collisions += (bd->stat >> 4) & 0xf;
 	netdev->stats.tx_bytes += bd->stat >> 16;
 	netdev->stats.tx_packets++;
-	return 0;
 }
 
-static void ethoc_tx(struct net_device *dev)
+static int ethoc_tx(struct net_device *dev, int limit)
 {
 	struct ethoc *priv = netdev_priv(dev);
+	int count;
+	struct ethoc_bd bd;
 
-	spin_lock(&priv->lock);
+	for (count = 0; count < limit; ++count) {
+		unsigned int entry;
 
-	while (priv->dty_tx != priv->cur_tx) {
-		unsigned int entry = priv->dty_tx % priv->num_tx;
-		struct ethoc_bd bd;
+		entry = priv->dty_tx & (priv->num_tx-1);
 
 		ethoc_read_bd(priv, entry, &bd);
-		if (bd.stat & TX_BD_READY)
-			break;
 
-		entry = (++priv->dty_tx) % priv->num_tx;
-		(void)ethoc_update_tx_stats(priv, &bd);
+		if (bd.stat & TX_BD_READY || (priv->dty_tx == priv->cur_tx)) {
+			ethoc_ack_irq(priv, INT_MASK_TX);
+			/* If interrupt came in between reading in the BD
+			 * and clearing the interrupt source, then we risk
+			 * missing the event as the TX interrupt won't trigger
+			 * right away when we reenable it; hence, check
+			 * BD_EMPTY here again to make sure there isn't such an
+			 * event pending...
+			 */
+			ethoc_read_bd(priv, entry, &bd);
+			if (bd.stat & TX_BD_READY ||
+			    (priv->dty_tx == priv->cur_tx))
+				break;
+		}
+
+		ethoc_update_tx_stats(priv, &bd);
+		priv->dty_tx++;
 	}
 
 	if ((priv->cur_tx - priv->dty_tx) <= (priv->num_tx / 2))
 		netif_wake_queue(dev);
 
-	ethoc_ack_irq(priv, INT_MASK_TX);
-	spin_unlock(&priv->lock);
+	return count;
 }
 
 static irqreturn_t ethoc_interrupt(int irq, void *dev_id)
@@ -515,32 +538,38 @@ static irqreturn_t ethoc_interrupt(int irq, void *dev_id)
 	struct net_device *dev = dev_id;
 	struct ethoc *priv = netdev_priv(dev);
 	u32 pending;
-
-	ethoc_disable_irq(priv, INT_MASK_ALL);
+	u32 mask;
+
+	/* Figure out what triggered the interrupt...
+	 * The tricky bit here is that the interrupt source bits get
+	 * set in INT_SOURCE for an event irregardless of whether that
+	 * event is masked or not.  Thus, in order to figure out what
+	 * triggered the interrupt, we need to remove the sources
+	 * for all events that are currently masked.  This behaviour
+	 * is not particularly well documented but reasonable...
+	 */
+	mask = ethoc_read(priv, INT_MASK);
 	pending = ethoc_read(priv, INT_SOURCE);
+	pending &= mask;
+
 	if (unlikely(pending == 0)) {
-		ethoc_enable_irq(priv, INT_MASK_ALL);
 		return IRQ_NONE;
 	}
 
 	ethoc_ack_irq(priv, pending);
 
+	/* We always handle the dropped packet interrupt */
 	if (pending & INT_MASK_BUSY) {
 		dev_err(&dev->dev, "packet dropped\n");
 		dev->stats.rx_dropped++;
 	}
 
-	if (pending & INT_MASK_RX) {
-		if (napi_schedule_prep(&priv->napi))
-			__napi_schedule(&priv->napi);
-	} else {
-		ethoc_enable_irq(priv, INT_MASK_RX);
+	/* Handle receive/transmit event by switching to polling */
+	if (pending & (INT_MASK_TX | INT_MASK_RX)) {
+		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
+		napi_schedule(&priv->napi);
 	}
 
-	if (pending & INT_MASK_TX)
-		ethoc_tx(dev);
-
-	ethoc_enable_irq(priv, INT_MASK_ALL & ~INT_MASK_RX);
 	return IRQ_HANDLED;
 }
 
@@ -566,26 +595,29 @@ static int ethoc_get_mac_address(struct net_device *dev, void *addr)
 static int ethoc_poll(struct napi_struct *napi, int budget)
 {
 	struct ethoc *priv = container_of(napi, struct ethoc, napi);
-	int work_done = 0;
+	int rx_work_done = 0;
+	int tx_work_done = 0;
+
+	rx_work_done = ethoc_rx(priv->netdev, budget);
+	tx_work_done = ethoc_tx(priv->netdev, budget);
 
-	work_done = ethoc_rx(priv->netdev, budget);
-	if (work_done < budget) {
-		ethoc_enable_irq(priv, INT_MASK_RX);
+	if (rx_work_done < budget && tx_work_done < budget) {
 		napi_complete(napi);
+		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
 	}
 
-	return work_done;
+	return rx_work_done;
 }
 
 static int ethoc_mdio_read(struct mii_bus *bus, int phy, int reg)
 {
-	unsigned long timeout = jiffies + ETHOC_MII_TIMEOUT;
 	struct ethoc *priv = bus->priv;
+	int i;
 
 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_READ);
 
-	while (time_before(jiffies, timeout)) {
+	for (i=0; i < 5; i++) {
 		u32 status = ethoc_read(priv, MIISTATUS);
 		if (!(status & MIISTATUS_BUSY)) {
 			u32 data = ethoc_read(priv, MIIRX_DATA);
@@ -593,8 +625,7 @@ static int ethoc_mdio_read(struct mii_bus *bus, int phy, int reg)
 			ethoc_write(priv, MIICOMMAND, 0);
 			return data;
 		}
-
-		schedule();
+		usleep_range(100,200);
 	}
 
 	return -EBUSY;
@@ -602,22 +633,21 @@ static int ethoc_mdio_read(struct mii_bus *bus, int phy, int reg)
 
 static int ethoc_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
 {
-	unsigned long timeout = jiffies + ETHOC_MII_TIMEOUT;
 	struct ethoc *priv = bus->priv;
+	int i;
 
 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
 	ethoc_write(priv, MIITX_DATA, val);
 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_WRITE);
 
-	while (time_before(jiffies, timeout)) {
+	for (i=0; i < 5; i++) {
 		u32 stat = ethoc_read(priv, MIISTATUS);
 		if (!(stat & MIISTATUS_BUSY)) {
 			/* reset MII command register */
 			ethoc_write(priv, MIICOMMAND, 0);
 			return 0;
 		}
-
-		schedule();
+		usleep_range(100,200);
 	}
 
 	return -EBUSY;
@@ -971,9 +1001,17 @@ static int __devinit ethoc_probe(struct platform_device *pdev)
 	/* calculate the number of TX/RX buffers, maximum 128 supported */
 	num_bd = min_t(unsigned int,
 		128, (netdev->mem_end - netdev->mem_start + 1) / ETHOC_BUFSIZ);
-	priv->num_tx = max(2, num_bd / 4);
+	if (num_bd < 4) {
+		ret = -ENODEV;
+		goto error;
+	}
+	/* num_tx must be a power of two */
+	priv->num_tx = rounddown_pow_of_two(num_bd >> 1);
 	priv->num_rx = num_bd - priv->num_tx;
 
+	dev_dbg(&pdev->dev, "ethoc: num_tx: %d num_rx: %d\n",
+		priv->num_tx, priv->num_rx);
+
 	priv->vma = devm_kzalloc(&pdev->dev, num_bd*sizeof(void*), GFP_KERNEL);
 	if (!priv->vma) {
 		ret = -ENOMEM;
@@ -982,10 +1020,23 @@ static int __devinit ethoc_probe(struct platform_device *pdev)
 
 	/* Allow the platform setup code to pass in a MAC address. */
 	if (pdev->dev.platform_data) {
-		struct ethoc_platform_data *pdata =
-			(struct ethoc_platform_data *)pdev->dev.platform_data;
+		struct ethoc_platform_data *pdata = pdev->dev.platform_data;
 		memcpy(netdev->dev_addr, pdata->hwaddr, IFHWADDRLEN);
 		priv->phy_id = pdata->phy_id;
+	} else {
+		priv->phy_id = -1;
+
+#ifdef CONFIG_OF
+		{
+		const uint8_t* mac;
+
+		mac = of_get_property(pdev->dev.of_node,
+				      "local-mac-address",
+				      NULL);
+		if (mac)
+			memcpy(netdev->dev_addr, mac, IFHWADDRLEN);
+		}
+#endif
 	}
 
 	/* Check that the given MAC address is valid. If it isn't, read the
@@ -1046,7 +1097,6 @@ static int __devinit ethoc_probe(struct platform_device *pdev)
 	/* setup NAPI */
 	netif_napi_add(netdev, &priv->napi, ethoc_poll, 64);
 
-	spin_lock_init(&priv->rx_lock);
 	spin_lock_init(&priv->lock);
 
 	ret = register_netdev(netdev);
@@ -1113,6 +1163,16 @@ static int ethoc_resume(struct platform_device *pdev)
 # define ethoc_resume  NULL
 #endif
 
+#ifdef CONFIG_OF
+static struct of_device_id ethoc_match[] = {
+	{
+		.compatible = "opencores,ethoc",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, ethoc_match);
+#endif
+
 static struct platform_driver ethoc_driver = {
 	.probe   = ethoc_probe,
 	.remove  = __devexit_p(ethoc_remove),
@@ -1120,6 +1180,10 @@ static struct platform_driver ethoc_driver = {
 	.resume  = ethoc_resume,
 	.driver  = {
 		.name = "ethoc",
+		.owner = THIS_MODULE,
+#ifdef CONFIG_OF
+		.of_match_table = ethoc_match,
+#endif
 	},
 };