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 <dai.haruki@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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 @@
}
/* 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 @@
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 @@
/* 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 @@
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 @@
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 @@
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 @@
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);