Commit d080cd63 authored by Dai Haruki's avatar Dai Haruki Committed by Jeff Garzik
Browse files

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: default avatarDai Haruki <dai.haruki@freescale.com>
Signed-off-by: default avatarAndy Fleming <afleming@freescale.com>
Signed-off-by: default avatarJeff Garzik <jgarzik@redhat.com>
parent 0b50d753

drivers/net/gianfar.c

+42 −14
Original line number Diff line number Diff line
@@ -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);

drivers/net/gianfar.h

+11 −2
Original line number Diff line number Diff line
@@ -126,9 +126,16 @@ extern const char gfar_driver_version[]; 
#define DEFAULT_TXCOUNT	16

#define DEFAULT_TXTIME	21



#define DEFAULT_RXTIME	21



/* Non NAPI Case */

#ifndef CONFIG_GFAR_NAPI

#define DEFAULT_RX_COALESCE 1

#define DEFAULT_RXCOUNT	16

#define DEFAULT_RXTIME	21

#else

#define DEFAULT_RX_COALESCE 0

#define DEFAULT_RXCOUNT	0

#endif /* CONFIG_GFAR_NAPI */



#define TBIPA_VALUE		0x1f

#define MIIMCFG_INIT_VALUE	0x00000007
@@ -242,6 +249,7 @@ extern const char gfar_driver_version[]; 
#define IEVENT_PERR		0x00000001

#define IEVENT_RX_MASK          (IEVENT_RXB0 | IEVENT_RXF0)

#define IEVENT_TX_MASK          (IEVENT_TXB | IEVENT_TXF)

#define IEVENT_RTX_MASK         (IEVENT_RX_MASK | IEVENT_TX_MASK)

#define IEVENT_ERR_MASK         \

(IEVENT_RXC | IEVENT_BSY | IEVENT_EBERR | IEVENT_MSRO | \

 IEVENT_BABT | IEVENT_TXC | IEVENT_TXE | IEVENT_LC \
@@ -269,11 +277,12 @@ extern const char gfar_driver_version[]; 
#define IMASK_FIQ		0x00000004

#define IMASK_DPE		0x00000002

#define IMASK_PERR		0x00000001

#define IMASK_RX_DISABLED ~(IMASK_RXFEN0 | IMASK_BSY)

#define IMASK_DEFAULT  (IMASK_TXEEN | IMASK_TXFEN | IMASK_TXBEN | \

		IMASK_RXFEN0 | IMASK_BSY | IMASK_EBERR | IMASK_BABR | \

		IMASK_XFUN | IMASK_RXC | IMASK_BABT | IMASK_DPE \

		| IMASK_PERR)

#define IMASK_RTX_DISABLED ((~(IMASK_RXFEN0 | IMASK_TXFEN | IMASK_BSY)) \

			   & IMASK_DEFAULT)



/* Fifo management */

#define FIFO_TX_THR_MASK	0x01ff