ar7-2.6: make cpmac robust against hardware quirks when the tx or rx dma ring runs...

SVN-Revision: 7018

diff --git a/target/linux/ar7-2.6/files/drivers/net/cpmac.c b/target/linux/ar7-2.6/files/drivers/net/cpmac.c
index 9847a41ce9fd1318f54ba0dfc1fd48150bde03f1..a3862e5a1b1cacbc46147e4cb31e257c4f33731f 100644 (file)
--- a/target/linux/ar7-2.6/files/drivers/net/cpmac.c
+++ b/target/linux/ar7-2.6/files/drivers/net/cpmac.c
@@ -197,7 +197,7 @@ struct cpmac_priv {
        spinlock_t lock;
        struct sk_buff *skb_pool;
        int free_skbs;
-       struct cpmac_desc *rx_head;
+       struct cpmac_desc *rx_head, *rx_tail;
        int tx_head, tx_tail;
        struct cpmac_desc *desc_ring;
        struct cpmac_regs *regs;
@@ -209,9 +209,12 @@ struct cpmac_priv {
        u32 msg_enable;
        struct net_device *dev;
        struct work_struct alloc_work;
+       struct work_struct reset_work;
 };
 
 static irqreturn_t cpmac_irq(int, void *);
+static int cpmac_stop(struct net_device *dev);
+static int cpmac_open(struct net_device *dev);
 
 #define CPMAC_LOW_THRESH 8
 #define CPMAC_ALLOC_SIZE 32
@@ -373,15 +376,18 @@ static void cpmac_rx(struct net_device *dev, int channel)
        char *data;
        struct sk_buff *skb;
        struct cpmac_desc *desc;
+       struct cpmac_desc *start;
        struct cpmac_priv *priv = netdev_priv(dev);
 
        spin_lock(&priv->lock);
        if (unlikely(!priv->rx_head))
                return;
 
-       desc = priv->rx_head;
-       dma_cache_inv((u32)desc, 16);
 
+       desc = priv->rx_tail->next;
+       dma_cache_inv((u32)desc, 16);
+       
+       start = priv->rx_tail;
        while((desc->dataflags & CPMAC_OWN) == 0) {
                priv->regs->rx_ack[0] = virt_to_phys(desc);
                if (unlikely(!desc->datalen)) {
@@ -407,19 +413,31 @@ static void cpmac_rx(struct net_device *dev, int channel)
                        if (printk_ratelimit())
                                printk(KERN_NOTICE "%s: rx: no free skbs, dropping packet\n",
                                       dev->name);
+                       priv->regs->rx_ptr[0] = virt_to_phys(desc);
                        priv->stats.rx_dropped++;
                }
                desc->hw_data = virt_to_phys(desc->skb->data);
                desc->buflen = CPMAC_SKB_SIZE;
                desc->dataflags = CPMAC_OWN;
+               desc->hw_next = 0;
                dma_cache_wback((u32)desc, 16);
+
+               priv->rx_tail->hw_next = virt_to_phys(desc);
+               priv->rx_tail->dataflags = CPMAC_OWN;
+               dma_cache_wback((u32)priv->rx_tail, 16);
+
+               priv->rx_tail = desc;
                desc = desc->next;
                dma_cache_inv((u32)desc, 16);
+               if (start == desc) {
+                       printk("Somebody set up us the bomb!!\n");
+                       break;
+               }
        }
 out:
        priv->rx_head = desc;
+       priv->regs->rx_ptr[0] = virt_to_phys(desc);
        spin_unlock(&priv->lock);
-       priv->regs->rx_ptr[0] = virt_to_phys(priv->rx_head);
 }
 
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
@@ -493,6 +511,15 @@ static int cpmac_start_xmit(struct sk_buff *skb, struct net_device *dev)
                netif_stop_queue(dev);
 
        desc = &priv->desc_ring[chan];
+       dma_cache_inv((u32)desc, 16);
+       if (desc->dataflags & CPMAC_OWN) {
+               printk(KERN_NOTICE "%s: tx dma ring full, dropping\n", dev->name);
+               spin_lock_irqsave(&priv->lock, flags);
+               priv->stats.tx_dropped++;
+               spin_unlock_irqrestore(&priv->lock, flags);
+               return -ENOMEM;
+       }
+
        dev->trans_start = jiffies;
        desc->jiffies = dev->trans_start;
        spin_unlock_irqrestore(&priv->lock, flags);
@@ -529,9 +556,9 @@ static void cpmac_end_xmit(struct net_device *dev, int channel)
                                        break;
                                desc = &priv->desc_ring[priv->tx_head];
                        }
-                       if (netif_queue_stopped(dev))
-                               netif_wake_queue(dev);
                }
+               if (netif_queue_stopped(dev))
+                       netif_wake_queue(dev);
        } else {
                if (printk_ratelimit())
                        printk(KERN_NOTICE "%s: end_xmit: spurious interrupt\n",
@@ -540,6 +567,40 @@ static void cpmac_end_xmit(struct net_device *dev, int channel)
        spin_unlock(&priv->lock);
 }
 
+static void cpmac_reset(struct net_device *dev)
+{
+       int i;
+       struct cpmac_priv *priv = netdev_priv(dev);
+
+       ar7_device_reset(priv->config->reset_bit);
+       priv->regs->rx_ctrl.control &= ~1;
+       priv->regs->tx_ctrl.control &= ~1;
+       for (i = 0; i < 8; i++) {
+               priv->regs->tx_ptr[i] = 0;
+               priv->regs->rx_ptr[i] = 0;
+       }
+       priv->regs->mac_control &= ~MAC_MII; /* disable mii */
+}
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
+static void
+cpmac_full_reset(struct work_struct *work)
+{
+        struct cpmac_priv *priv = container_of(work, struct cpmac_priv,
+                                              alloc_work);
+        struct net_device *dev = priv->dev;
+#else
+static void
+cpmac_full_reset(void *data)
+{
+        struct net_device *dev = (struct net_device*)data;
+#endif
+
+       cpmac_stop(dev);
+       cpmac_open(dev);
+}
+
+
 static irqreturn_t cpmac_irq(int irq, void *dev_id)
 {
        struct net_device *dev = (struct net_device *)dev_id;
@@ -560,9 +621,11 @@ static irqreturn_t cpmac_irq(int irq, void *dev_id)
        }
 
        if (unlikely(status & INTST_HOST)) { /* host interrupt ??? */
-               printk("%s: host int, something bad happened...\n", dev->name);
-               printk("%s: mac status: 0x%08x\n", dev->name,
-                      priv->regs->mac_status);
+               printk("%s: host int, something bad happened - mac status: 0x%08x\n", dev->name, priv->regs->mac_status);
+
+               /* try to recover */
+               cpmac_reset(dev);
+               schedule_work(&priv->reset_work);
        }
 
        if (unlikely(status & INTST_STATUS)) { /* status interrupt ??? */
@@ -665,21 +728,6 @@ static int cpmac_change_mtu(struct net_device *dev, int mtu)
        return 0;
 }
 
-static void cpmac_reset(struct net_device *dev)
-{
-       int i;
-       struct cpmac_priv *priv = netdev_priv(dev);
-
-       ar7_device_reset(priv->config->reset_bit);
-       priv->regs->rx_ctrl.control &= ~1;
-       priv->regs->tx_ctrl.control &= ~1;
-       for (i = 0; i < 8; i++) {
-               priv->regs->tx_ptr[i] = 0;
-               priv->regs->rx_ptr[i] = 0;
-       }
-       priv->regs->mac_control &= ~MAC_MII; /* disable mii */
-}
-
 static void cpmac_adjust_link(struct net_device *dev)
 {
        struct cpmac_priv *priv = netdev_priv(dev);
@@ -767,8 +815,10 @@ static int cpmac_open(struct net_device *dev)
 
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
         INIT_WORK(&priv->alloc_work, cpmac_alloc_skbs);
+        INIT_WORK(&priv->reset_work, cpmac_full_reset);
 #else
         INIT_WORK(&priv->alloc_work, cpmac_alloc_skbs, dev);
+        INIT_WORK(&priv->reset_work, cpmac_full_reset, dev);
 #endif
        schedule_work(&priv->alloc_work);
        flush_scheduled_work();
@@ -788,9 +838,9 @@ static int cpmac_open(struct net_device *dev)
                desc->hw_next = virt_to_phys(desc->next);
                dma_cache_wback((u32)desc, 16);
        }
-       priv->rx_head[CPMAC_RX_RING_SIZE - 1].next = priv->rx_head;
-       priv->rx_head[CPMAC_RX_RING_SIZE - 1].hw_next =
-               virt_to_phys(priv->rx_head);
+       priv->rx_tail = &priv->rx_head[CPMAC_RX_RING_SIZE - 1];
+       priv->rx_tail->next = priv->rx_head;
+       priv->rx_tail->hw_next = 0;
 
        cpmac_reset(dev);
        for (i = 0; i < 8; i++)
@@ -828,7 +878,6 @@ static int cpmac_open(struct net_device *dev)
        phy_start(priv->phy);
 
        netif_start_queue(dev);
-
        return 0;
 
 fail_irq: