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
         },
 };