From d080cd6301e107e79c6a0fc654319f8979f70549 Mon Sep 17 00:00:00 2001 From: Dai Haruki Date: Wed, 9 Apr 2008 19:37:51 -0500 Subject: gianfar: Support NAPI for TX Frames Poll the completed TX frames in gfar_poll(). This prevents the tx completion interrupt from interfering with processing of received frames. We also disable hardware rx coalescing when NAPI is enabled. Signed-off-by: Dai Haruki Signed-off-by: Andy Fleming Signed-off-by: Jeff Garzik --- drivers/net/gianfar.c | 56 ++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 42 insertions(+), 14 deletions(-) (limited to 'drivers/net/gianfar.c') diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c index 601f93e..c8c3df7 100644 --- a/drivers/net/gianfar.c +++ b/drivers/net/gianfar.c @@ -1250,17 +1250,12 @@ static void gfar_timeout(struct net_device *dev) } /* Interrupt Handler for Transmit complete */ -static irqreturn_t gfar_transmit(int irq, void *dev_id) +int gfar_clean_tx_ring(struct net_device *dev) { - struct net_device *dev = (struct net_device *) dev_id; - struct gfar_private *priv = netdev_priv(dev); struct txbd8 *bdp; + struct gfar_private *priv = netdev_priv(dev); + int howmany = 0; - /* Clear IEVENT */ - gfar_write(&priv->regs->ievent, IEVENT_TX_MASK); - - /* Lock priv */ - spin_lock(&priv->txlock); bdp = priv->dirty_tx; while ((bdp->status & TXBD_READY) == 0) { /* If dirty_tx and cur_tx are the same, then either the */ @@ -1269,7 +1264,7 @@ static irqreturn_t gfar_transmit(int irq, void *dev_id) if ((bdp == priv->cur_tx) && (netif_queue_stopped(dev) == 0)) break; - dev->stats.tx_packets++; + howmany++; /* Deferred means some collisions occurred during transmit, */ /* but we eventually sent the packet. */ @@ -1278,11 +1273,15 @@ static irqreturn_t gfar_transmit(int irq, void *dev_id) /* Free the sk buffer associated with this TxBD */ dev_kfree_skb_irq(priv->tx_skbuff[priv->skb_dirtytx]); + priv->tx_skbuff[priv->skb_dirtytx] = NULL; priv->skb_dirtytx = (priv->skb_dirtytx + 1) & TX_RING_MOD_MASK(priv->tx_ring_size); + /* Clean BD length for empty detection */ + bdp->length = 0; + /* update bdp to point at next bd in the ring (wrapping if necessary) */ if (bdp->status & TXBD_WRAP) bdp = priv->tx_bd_base; @@ -1297,6 +1296,25 @@ static irqreturn_t gfar_transmit(int irq, void *dev_id) netif_wake_queue(dev); } /* while ((bdp->status & TXBD_READY) == 0) */ + dev->stats.tx_packets += howmany; + + return howmany; +} + +/* Interrupt Handler for Transmit complete */ +static irqreturn_t gfar_transmit(int irq, void *dev_id) +{ + struct net_device *dev = (struct net_device *) dev_id; + struct gfar_private *priv = netdev_priv(dev); + + /* Clear IEVENT */ + gfar_write(&priv->regs->ievent, IEVENT_TX_MASK); + + /* Lock priv */ + spin_lock(&priv->txlock); + + gfar_clean_tx_ring(dev); + /* If we are coalescing the interrupts, reset the timer */ /* Otherwise, clear it */ if (likely(priv->txcoalescing)) { @@ -1392,15 +1410,15 @@ irqreturn_t gfar_receive(int irq, void *dev_id) unsigned long flags; #endif - /* Clear IEVENT, so rx interrupt isn't called again - * because of this interrupt */ - gfar_write(&priv->regs->ievent, IEVENT_RX_MASK); - /* support NAPI */ #ifdef CONFIG_GFAR_NAPI + /* Clear IEVENT, so interrupts aren't called again + * because of the packets that have already arrived */ + gfar_write(&priv->regs->ievent, IEVENT_RTX_MASK); + if (netif_rx_schedule_prep(dev, &priv->napi)) { tempval = gfar_read(&priv->regs->imask); - tempval &= IMASK_RX_DISABLED; + tempval &= IMASK_RTX_DISABLED; gfar_write(&priv->regs->imask, tempval); __netif_rx_schedule(dev, &priv->napi); @@ -1411,6 +1429,9 @@ irqreturn_t gfar_receive(int irq, void *dev_id) gfar_read(&priv->regs->imask)); } #else + /* Clear IEVENT, so rx interrupt isn't called again + * because of this interrupt */ + gfar_write(&priv->regs->ievent, IEVENT_RX_MASK); spin_lock_irqsave(&priv->rxlock, flags); gfar_clean_rx_ring(dev, priv->rx_ring_size); @@ -1580,6 +1601,13 @@ static int gfar_poll(struct napi_struct *napi, int budget) struct gfar_private *priv = container_of(napi, struct gfar_private, napi); struct net_device *dev = priv->dev; int howmany; + unsigned long flags; + + /* If we fail to get the lock, don't bother with the TX BDs */ + if (spin_trylock_irqsave(&priv->txlock, flags)) { + gfar_clean_tx_ring(dev); + spin_unlock_irqrestore(&priv->txlock, flags); + } howmany = gfar_clean_rx_ring(dev, budget); -- cgit v1.1