forcedeth: tx timeout fix

This patch fixes the tx_timeout() to properly handle the clean up of the
tx ring. It also sets the tx put pointer back to the correct position to
be in sync with HW.

Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/forcedeth.c b/drivers/net/forcedeth.c
index 11d5db16ed9c5a1beeaac4f9db55689b9f432796..f9a846b1b92f2816327000216ddbae46f4c3f7f6 100644 (file)
--- a/drivers/net/forcedeth.c
+++ b/drivers/net/forcedeth.c
@@ -1880,6 +1880,7 @@ static void nv_init_tx(struct net_device *dev)
        np->tx_pkts_in_progress = 0;
        np->tx_change_owner = NULL;
        np->tx_end_flip = NULL;
+       np->tx_stop = 0;
 
        for (i = 0; i < np->tx_ring_size; i++) {
                if (!nv_optimized(np)) {
@@ -2530,6 +2531,8 @@ static void nv_tx_timeout(struct net_device *dev)
        struct fe_priv *np = netdev_priv(dev);
        u8 __iomem *base = get_hwbase(dev);
        u32 status;
+       union ring_type put_tx;
+       int saved_tx_limit;
 
        if (np->msi_flags & NV_MSI_X_ENABLED)
                status = readl(base + NvRegMSIXIrqStatus) & NVREG_IRQSTAT_MASK;
@@ -2589,24 +2592,32 @@ static void nv_tx_timeout(struct net_device *dev)
        /* 1) stop tx engine */
        nv_stop_tx(dev);
 
-       /* 2) check that the packets were not sent already: */
+       /* 2) complete any outstanding tx and do not give HW any limited tx pkts */
+       saved_tx_limit = np->tx_limit;
+       np->tx_limit = 0; /* prevent giving HW any limited pkts */
+       np->tx_stop = 0;  /* prevent waking tx queue */
        if (!nv_optimized(np))
                nv_tx_done(dev, np->tx_ring_size);
        else
                nv_tx_done_optimized(dev, np->tx_ring_size);
 
-       /* 3) if there are dead entries: clear everything */
-       if (np->get_tx_ctx != np->put_tx_ctx) {
-               printk(KERN_DEBUG "%s: tx_timeout: dead entries!\n", dev->name);
-               nv_drain_tx(dev);
-               nv_init_tx(dev);
-               setup_hw_rings(dev, NV_SETUP_TX_RING);
-       }
+       /* save current HW postion */
+       if (np->tx_change_owner)
+               put_tx.ex = np->tx_change_owner->first_tx_desc;
+       else
+               put_tx = np->put_tx;
 
-       netif_wake_queue(dev);
+       /* 3) clear all tx state */
+       nv_drain_tx(dev);
+       nv_init_tx(dev);
+
+       /* 4) restore state to current HW position */
+       np->get_tx = np->put_tx = put_tx;
+       np->tx_limit = saved_tx_limit;
 
-       /* 4) restart tx engine */
+       /* 5) restart tx engine */
        nv_start_tx(dev);
+       netif_wake_queue(dev);
        spin_unlock_irq(&np->lock);
 }