Subject: [PATCH 8/9] pcnet32: NAPI implementation.

From: Don Fry <[email-masked]>
Date: Thu, 29 Jun 2006 13:55:51 -0700

Implement NAPI changes to pcnet32 driver.  Compile default is off.
Listed as experimental.

Len and Don both worked on a NAPI implementation and have both tested
these changes. 

An e1000 blasting short packets to the pcnet32 will lockup Don's system
until the receive storm stops.  Without NAPI Len's system watchdog would
expire causing the system to reboot.  With NAPI the system will stay
operational.

Tested ia32 and ppc64.  Tested '970A, '971, '972, '973, '975, '976, and
'978.

The Kconfig changes came from Len.  Don is to blame for all the others.

Signed-off-by: Len Sorensen <[email-masked]>
Signed-off-by: Don Fry <[email-masked]>

--- linux-2.6.17-git13/drivers/net/orig.Kconfig	Wed Jun 28 10:38:45 2006
+++ linux-2.6.17-git13/drivers/net/Kconfig	Wed Jun 28 15:36:25 2006
@@ -1300,6 +1300,23 @@ config PCNET32
 	  <file:Documentation/networking/net-modules.txt>. The module
 	  will be called pcnet32.
 
+config PCNET32_NAPI
+	bool "Use RX polling (NAPI) (EXPERIMENTAL)"
+	depends on PCNET32 && EXPERIMENTAL
+	help
+	  NAPI is a new driver API designed to reduce CPU and interrupt load
+	  when the driver is receiving lots of packets from the card. It is
+	  still somewhat experimental and thus not yet enabled by default.
+
+	  If your estimated Rx load is 10kpps or more, or if the card will be
+	  deployed on potentially unfriendly networks (e.g. in a firewall),
+	  then say Y here.
+
+	  See <file:Documentation/networking/NAPI_HOWTO.txt> for more
+	  information.
+
+	  If in doubt, say N.
+
 config AMD8111_ETH
 	tristate "AMD 8111 (new PCI lance) support"
 	depends on NET_PCI && PCI
--- linux-2.6.17-git13/drivers/net/purge.pcnet32.c	Thu Jun 29 13:28:24 2006
+++ linux-2.6.17-git13/drivers/net/pcnet32.c	Thu Jun 29 13:28:31 2006
@@ -21,9 +21,15 @@
  *
  *************************************************************************/
 
+#include <linux/config.h>
+
 #define DRV_NAME	"pcnet32"
-#define DRV_VERSION	"1.32"
-#define DRV_RELDATE	"18.Mar.2006"
+#ifdef CONFIG_PCNET32_NAPI
+#define DRV_VERSION	"1.33-NAPI"
+#else
+#define DRV_VERSION	"1.33"
+#endif
+#define DRV_RELDATE	"27.Jun.2006"
 #define PFX		DRV_NAME ": "
 
 static const char *const version =
@@ -296,7 +302,6 @@ static int pcnet32_probe1(unsigned long,
 static int pcnet32_open(struct net_device *);
 static int pcnet32_init_ring(struct net_device *);
 static int pcnet32_start_xmit(struct sk_buff *, struct net_device *);
-static int pcnet32_rx(struct net_device *);
 static void pcnet32_tx_timeout(struct net_device *dev);
 static irqreturn_t pcnet32_interrupt(int, void *, struct pt_regs *);
 static int pcnet32_close(struct net_device *);
@@ -878,7 +883,11 @@ static int pcnet32_loopback_test(struct 
 	rc = 1;			/* default to fail */
 
 	if (netif_running(dev))
+#ifdef CONFIG_PCNET32_NAPI
+		pcnet32_netif_stop(dev);
+#else
 		pcnet32_close(dev);
+#endif
 
 	spin_lock_irqsave(&lp->lock, flags);
 	lp->a.write_csr(ioaddr, CSR0, CSR0_STOP);	/* stop the chip */
@@ -1010,6 +1019,16 @@ static int pcnet32_loopback_test(struct 
 	x = a->read_bcr(ioaddr, 32);	/* reset internal loopback */
 	a->write_bcr(ioaddr, 32, (x & ~0x0002));
 
+#ifdef CONFIG_PCNET32_NAPI
+	if (netif_running(dev)) {
+		pcnet32_netif_start(dev);
+		pcnet32_restart(dev, CSR0_NORMAL);
+	} else {
+		pcnet32_purge_rx_ring(dev);
+		lp->a.write_bcr(ioaddr, 20, 4);	/* return to 16bit mode */
+	}
+	spin_unlock_irqrestore(&lp->lock, flags);
+#else
 	if (netif_running(dev)) {
 		spin_unlock_irqrestore(&lp->lock, flags);
 		pcnet32_open(dev);
@@ -1018,6 +1037,7 @@ static int pcnet32_loopback_test(struct 
 		lp->a.write_bcr(ioaddr, 20, 4);	/* return to 16bit mode */
 		spin_unlock_irqrestore(&lp->lock, flags);
 	}
+#endif
 
 	return (rc);
 }				/* end pcnet32_loopback_test  */
@@ -1116,6 +1136,285 @@ static int pcnet32_suspend(struct net_de
 	return 1;
 }
 
+static int pcnet32_rx_entry(struct net_device *dev,
+			    struct pcnet32_private *lp,
+			    struct pcnet32_rx_head *rxp,
+			    int entry)
+{
+	int status = (short)le16_to_cpu(rxp->status) >> 8;
+	int rx_in_place = 0;
+	struct sk_buff *skb;
+	short pkt_len;
+
+	if (status != 0x03) {	/* There was an error. */
+		/*
+		 * There is a tricky error noted by John Murphy,
+		 * <[email-masked]> to Russ Nelson: Even with full-sized
+		 * buffers it's possible for a jabber packet to use two
+		 * buffers, with only the last correctly noting the error.
+		 */
+		if (status & 0x01)	/* Only count a general error at the */
+			lp->stats.rx_errors++;	/* end of a packet. */
+		if (status & 0x20)
+			lp->stats.rx_frame_errors++;
+		if (status & 0x10)
+			lp->stats.rx_over_errors++;
+		if (status & 0x08)
+			lp->stats.rx_crc_errors++;
+		if (status & 0x04)
+			lp->stats.rx_fifo_errors++;
+		return 1;
+	}
+
+	pkt_len = (le32_to_cpu(rxp->msg_length) & 0xfff) - 4;
+
+	/* Discard oversize frames. */
+	if (unlikely(pkt_len > PKT_BUF_SZ - 2)) {
+		if (netif_msg_drv(lp))
+			printk(KERN_ERR "%s: Impossible packet size %d!\n",
+			       dev->name, pkt_len);
+		lp->stats.rx_errors++;
+		return 1;
+	}
+	if (pkt_len < 60) {
+		if (netif_msg_rx_err(lp))
+			printk(KERN_ERR "%s: Runt packet!\n", dev->name);
+		lp->stats.rx_errors++;
+		return 1;
+	}
+
+	if (pkt_len > rx_copybreak) {
+		struct sk_buff *newskb;
+
+		if ((newskb = dev_alloc_skb(PKT_BUF_SZ))) {
+			skb_reserve(newskb, 2);
+			skb = lp->rx_skbuff[entry];
+			pci_unmap_single(lp->pci_dev,
+					 lp->rx_dma_addr[entry],
+					 PKT_BUF_SZ - 2,
+					 PCI_DMA_FROMDEVICE);
+			skb_put(skb, pkt_len);
+			lp->rx_skbuff[entry] = newskb;
+			newskb->dev = dev;
+			lp->rx_dma_addr[entry] =
+			    pci_map_single(lp->pci_dev,
+					   newskb->data,
+					   PKT_BUF_SZ - 2,
+					   PCI_DMA_FROMDEVICE);
+			rxp->base = le32_to_cpu(lp->rx_dma_addr[entry]);
+			rx_in_place = 1;
+		} else
+			skb = NULL;
+	} else {
+		skb = dev_alloc_skb(pkt_len + 2);
+	}
+
+	if (skb == NULL) {
+		if (netif_msg_drv(lp))
+			printk(KERN_ERR
+			       "%s: Memory squeeze, dropping packet.\n",
+			       dev->name);
+		lp->stats.rx_dropped++;
+		return 1;
+	}
+	skb->dev = dev;
+	if (!rx_in_place) {
+		skb_reserve(skb, 2);	/* 16 byte align */
+		skb_put(skb, pkt_len);	/* Make room */
+		pci_dma_sync_single_for_cpu(lp->pci_dev,
+					    lp->rx_dma_addr[entry],
+					    PKT_BUF_SZ - 2,
+					    PCI_DMA_FROMDEVICE);
+		eth_copy_and_sum(skb,
+				 (unsigned char *)(lp->rx_skbuff[entry]->data),
+				 pkt_len, 0);
+		pci_dma_sync_single_for_device(lp->pci_dev,
+					       lp->rx_dma_addr[entry],
+					       PKT_BUF_SZ - 2,
+					       PCI_DMA_FROMDEVICE);
+	}
+	lp->stats.rx_bytes += skb->len;
+	lp->stats.rx_packets++;
+	skb->protocol = eth_type_trans(skb, dev);
+#ifdef CONFIG_PCNET32_NAPI
+	netif_receive_skb(skb);
+#else
+	netif_rx(skb);
+#endif
+	dev->last_rx = jiffies;
+	return 1;
+}
+
+static int pcnet32_rx(struct net_device *dev, int quota)
+{
+	struct pcnet32_private *lp = dev->priv;
+	int entry = lp->cur_rx & lp->rx_mod_mask;
+	struct pcnet32_rx_head *rxp = &lp->rx_ring[entry];
+	int npackets = 0;
+
+	/* If we own the next entry, it's a new packet. Send it up. */
+	while (quota > npackets && (short)le16_to_cpu(rxp->status) >= 0) {
+		npackets += pcnet32_rx_entry(dev, lp, rxp, entry);
+		/*
+		 * The docs say that the buffer length isn't touched, but Andrew
+		 * Boyd of QNX reports that some revs of the 79C965 clear it.
+		 */
+		rxp->buf_length = le16_to_cpu(2 - PKT_BUF_SZ);
+		wmb();	/* Make sure owner changes after others are visible */
+		rxp->status = le16_to_cpu(0x8000);
+		entry = (++lp->cur_rx) & lp->rx_mod_mask;
+		rxp = &lp->rx_ring[entry];
+	}
+
+	return npackets;
+}
+
+static int pcnet32_tx(struct net_device *dev)
+{
+	struct pcnet32_private *lp = dev->priv;
+	unsigned int dirty_tx = lp->dirty_tx;
+	int delta;
+	int must_restart = 0;
+
+	while (dirty_tx != lp->cur_tx) {
+		int entry = dirty_tx & lp->tx_mod_mask;
+		int status = (short)le16_to_cpu(lp->tx_ring[entry].status);
+
+		if (status < 0)
+			break;	/* It still hasn't been Txed */
+
+		lp->tx_ring[entry].base = 0;
+
+		if (status & 0x4000) {
+			/* There was an major error, log it. */
+			int err_status =
+			    le32_to_cpu(lp->tx_ring[entry].
+					misc);
+			lp->stats.tx_errors++;
+			if (netif_msg_tx_err(lp))
+				printk(KERN_ERR
+				       "%s: Tx error status=%04x err_status=%08x\n",
+				       dev->name, status,
+				       err_status);
+			if (err_status & 0x04000000)
+				lp->stats.tx_aborted_errors++;
+			if (err_status & 0x08000000)
+				lp->stats.tx_carrier_errors++;
+			if (err_status & 0x10000000)
+				lp->stats.tx_window_errors++;
+#ifndef DO_DXSUFLO
+			if (err_status & 0x40000000) {
+				lp->stats.tx_fifo_errors++;
+				/* Ackk!  On FIFO errors the Tx unit is turned off! */
+				/* Remove this verbosity later! */
+				if (netif_msg_tx_err(lp))
+					printk(KERN_ERR
+					       "%s: Tx FIFO error!\n",
+						dev->name);
+				must_restart = 1;
+			}
+#else
+			if (err_status & 0x40000000) {
+				lp->stats.tx_fifo_errors++;
+				if (!lp->dxsuflo) {	/* If controller doesn't recover ... */
+					/* Ackk!  On FIFO errors the Tx unit is turned off! */
+					/* Remove this verbosity later! */
+					if (netif_msg_tx_err(lp))
+						printk(KERN_ERR
+						       "%s: Tx FIFO error!\n",
+						       dev->name);
+					must_restart = 1;
+				}
+			}
+#endif
+		} else {
+			if (status & 0x1800)
+				lp->stats.collisions++;
+			lp->stats.tx_packets++;
+		}
+
+		/* We must free the original skb */
+		if (lp->tx_skbuff[entry]) {
+			pci_unmap_single(lp->pci_dev,
+					 lp->tx_dma_addr[entry],
+					 lp->tx_skbuff[entry]->
+					 len, PCI_DMA_TODEVICE);
+			dev_kfree_skb_any(lp->tx_skbuff[entry]);
+			lp->tx_skbuff[entry] = NULL;
+			lp->tx_dma_addr[entry] = 0;
+		}
+		dirty_tx++;
+	}
+
+	delta = (lp->cur_tx - dirty_tx) & (lp->tx_mod_mask + lp->tx_ring_size);
+	if (delta > lp->tx_ring_size) {
+		if (netif_msg_drv(lp))
+			printk(KERN_ERR
+			       "%s: out-of-sync dirty pointer, %d vs. %d, full=%d.\n",
+			       dev->name, dirty_tx, lp->cur_tx,
+			       lp->tx_full);
+		dirty_tx += lp->tx_ring_size;
+		delta -= lp->tx_ring_size;
+	}
+
+	if (lp->tx_full &&
+	    netif_queue_stopped(dev) &&
+	    delta < lp->tx_ring_size - 2) {
+		/* The ring is no longer full, clear tbusy. */
+		lp->tx_full = 0;
+		netif_wake_queue(dev);
+	}
+	lp->dirty_tx = dirty_tx;
+
+	return must_restart;
+}
+
+#ifdef CONFIG_PCNET32_NAPI
+static int pcnet32_poll(struct net_device *dev, int *budget)
+{
+	struct pcnet32_private *lp = dev->priv;
+	int quota = min(dev->quota, *budget);
+	unsigned long ioaddr = dev->base_addr;
+	u16 val;
+	unsigned long flags;
+
+	quota = pcnet32_rx(dev, quota);
+
+	spin_lock_irqsave(&lp->lock, flags);
+	if (pcnet32_tx(dev)) {
+		/* reset the chip to clear the error condition, then restart */
+		lp->a.reset(ioaddr);
+		lp->a.write_csr(ioaddr, CSR4, 0x0915);
+		pcnet32_restart(dev, CSR0_START);
+		netif_wake_queue(dev);
+	}
+	spin_unlock_irqrestore(&lp->lock, flags);
+
+	*budget -= quota;
+	dev->quota -= quota;
+
+	if (dev->quota == 0) {
+		return 1;
+	}
+
+	netif_rx_complete(dev);
+
+	spin_lock_irqsave(&lp->lock, flags);
+
+	/* clear interrupt masks */
+	val = lp->a.read_csr(ioaddr, CSR3);
+	val &= 0x00ff;
+	lp->a.write_csr(ioaddr, CSR3, val);
+
+	/* Set interrupt enable. */
+	lp->a.write_csr(ioaddr, CSR0, CSR0_INTEN);
+
+	spin_unlock_irqrestore(&lp->lock, flags);
+
+	return 0;
+}
+#endif
+
 #define PCNET32_REGS_PER_PHY	32
 #define PCNET32_MAX_PHYS	32
 static int pcnet32_get_regs_len(struct net_device *dev)
@@ -1651,6 +1950,10 @@ pcnet32_probe1(unsigned long ioaddr, int
 	dev->ethtool_ops = &pcnet32_ethtool_ops;
 	dev->tx_timeout = pcnet32_tx_timeout;
 	dev->watchdog_timeo = (5 * HZ);
+	dev->weight = lp->rx_ring_size / 2;
+#ifdef CONFIG_PCNET32_NAPI
+	dev->poll = pcnet32_poll;
+#endif
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
 	dev->poll_controller = pcnet32_poll_controller;
@@ -2253,9 +2556,9 @@ pcnet32_interrupt(int irq, void *dev_id,
 	struct net_device *dev = dev_id;
 	struct pcnet32_private *lp;
 	unsigned long ioaddr;
-	u16 csr0, rap;
 	int boguscnt = max_interrupt_work;
-	int must_restart;
+	u16 csr0;
+	irqreturn_t rc = IRQ_HANDLED;
 
 	if (!dev) {
 		if (pcnet32_debug & NETIF_MSG_INTR)
@@ -2269,141 +2572,33 @@ pcnet32_interrupt(int irq, void *dev_id,
 
 	spin_lock(&lp->lock);
 
-	rap = lp->a.read_rap(ioaddr);
-	while ((csr0 = lp->a.read_csr(ioaddr, 0)) & 0x8f00 && --boguscnt >= 0) {
-		if (csr0 == 0xffff) {
-			break;	/* PCMCIA remove happened */
-		}
+	csr0 = lp->a.read_csr(ioaddr, CSR0);
+	if (csr0 == 0xffff) {
+		rc = IRQ_NONE;
+	} else while (csr0 & 0x8f00 && --boguscnt >= 0) {
 		/* Acknowledge all of the current interrupt sources ASAP. */
-		lp->a.write_csr(ioaddr, 0, csr0 & ~0x004f);
-
-		must_restart = 0;
+		lp->a.write_csr(ioaddr, CSR0, csr0 & ~0x004f);
 
 		if (netif_msg_intr(lp))
 			printk(KERN_DEBUG
 			       "%s: interrupt  csr0=%#2.2x new csr=%#2.2x.\n",
-			       dev->name, csr0, lp->a.read_csr(ioaddr, 0));
-
-		if (csr0 & 0x0400)	/* Rx interrupt */
-			pcnet32_rx(dev);
-
-		if (csr0 & 0x0200) {	/* Tx-done interrupt */
-			unsigned int dirty_tx = lp->dirty_tx;
-			int delta;
-
-			while (dirty_tx != lp->cur_tx) {
-				int entry = dirty_tx & lp->tx_mod_mask;
-				int status =
-				    (short)le16_to_cpu(lp->tx_ring[entry].
-						       status);
-
-				if (status < 0)
-					break;	/* It still hasn't been Txed */
-
-				lp->tx_ring[entry].base = 0;
-
-				if (status & 0x4000) {
-					/* There was an major error, log it. */
-					int err_status =
-					    le32_to_cpu(lp->tx_ring[entry].
-							misc);
-					lp->stats.tx_errors++;
-					if (netif_msg_tx_err(lp))
-						printk(KERN_ERR
-						       "%s: Tx error status=%04x err_status=%08x\n",
-						       dev->name, status,
-						       err_status);
-					if (err_status & 0x04000000)
-						lp->stats.tx_aborted_errors++;
-					if (err_status & 0x08000000)
-						lp->stats.tx_carrier_errors++;
-					if (err_status & 0x10000000)
-						lp->stats.tx_window_errors++;
-#ifndef DO_DXSUFLO
-					if (err_status & 0x40000000) {
-						lp->stats.tx_fifo_errors++;
-						/* Ackk!  On FIFO errors the Tx unit is turned off! */
-						/* Remove this verbosity later! */
-						if (netif_msg_tx_err(lp))
-							printk(KERN_ERR
-							       "%s: Tx FIFO error! CSR0=%4.4x\n",
-							       dev->name, csr0);
-						must_restart = 1;
-					}
-#else
-					if (err_status & 0x40000000) {
-						lp->stats.tx_fifo_errors++;
-						if (!lp->dxsuflo) {	/* If controller doesn't recover ... */
-							/* Ackk!  On FIFO errors the Tx unit is turned off! */
-							/* Remove this verbosity later! */
-							if (netif_msg_tx_err
-							    (lp))
-								printk(KERN_ERR
-								       "%s: Tx FIFO error! CSR0=%4.4x\n",
-								       dev->
-								       name,
-								       csr0);
-							must_restart = 1;
-						}
-					}
-#endif
-				} else {
-					if (status & 0x1800)
-						lp->stats.collisions++;
-					lp->stats.tx_packets++;
-				}
-
-				/* We must free the original skb */
-				if (lp->tx_skbuff[entry]) {
-					pci_unmap_single(lp->pci_dev,
-							 lp->tx_dma_addr[entry],
-							 lp->tx_skbuff[entry]->
-							 len, PCI_DMA_TODEVICE);
-					dev_kfree_skb_irq(lp->tx_skbuff[entry]);
-					lp->tx_skbuff[entry] = NULL;
-					lp->tx_dma_addr[entry] = 0;
-				}
-				dirty_tx++;
-			}
-
-			delta =
-			    (lp->cur_tx - dirty_tx) & (lp->tx_mod_mask +
-						       lp->tx_ring_size);
-			if (delta > lp->tx_ring_size) {
-				if (netif_msg_drv(lp))
-					printk(KERN_ERR
-					       "%s: out-of-sync dirty pointer, %d vs. %d, full=%d.\n",
-					       dev->name, dirty_tx, lp->cur_tx,
-					       lp->tx_full);
-				dirty_tx += lp->tx_ring_size;
-				delta -= lp->tx_ring_size;
-			}
-
-			if (lp->tx_full &&
-			    netif_queue_stopped(dev) &&
-			    delta < lp->tx_ring_size - 2) {
-				/* The ring is no longer full, clear tbusy. */
-				lp->tx_full = 0;
-				netif_wake_queue(dev);
-			}
-			lp->dirty_tx = dirty_tx;
-		}
+			       dev->name, csr0, lp->a.read_csr(ioaddr, CSR0));
 
 		/* Log misc errors. */
 		if (csr0 & 0x4000)
 			lp->stats.tx_errors++;	/* Tx babble. */
 		if (csr0 & 0x1000) {
 			/*
-			 * this happens when our receive ring is full. This shouldn't
-			 * be a problem as we will see normal rx interrupts for the frames
-			 * in the receive ring. But there are some PCI chipsets (I can
-			 * reproduce this on SP3G with Intel saturn chipset) which have
-			 * sometimes problems and will fill up the receive ring with
-			 * error descriptors. In this situation we don't get a rx
-			 * interrupt, but a missed frame interrupt sooner or later.
-			 * So we try to clean up our receive ring here.
+			 * This happens when our receive ring is full. This
+			 * shouldn't be a problem as we will see normal rx
+			 * interrupts for the frames in the receive ring. But
+			 * there are some PCI chipsets (I can reproduce this
+			 * on SP3G with Intel saturn chipset) which have
+			 * sometimes problems and will fill up the receive
+			 * ring with error descriptors. In this situation we
+			 * don't get a rx interrupt, but a missed frame
+			 * interrupt sooner or later.
 			 */
-			pcnet32_rx(dev);
 			lp->stats.rx_errors++;	/* Missed a Rx frame. */
 		}
 		if (csr0 & 0x0800) {
@@ -2413,183 +2608,41 @@ pcnet32_interrupt(int irq, void *dev_id,
 				       dev->name, csr0);
 			/* unlike for the lance, there is no restart needed */
 		}
-
-		if (must_restart) {
+#ifdef CONFIG_PCNET32_NAPI
+		if (netif_rx_schedule_prep(dev)) {
+			u16 val;
+			/* set interrupt masks */
+			val = lp->a.read_csr(ioaddr, CSR3);
+			val |= 0x5f00;
+			lp->a.write_csr(ioaddr, CSR3, val);
+			__netif_rx_schedule(dev);
+			break;
+		}
+#else
+		pcnet32_rx(dev, dev->weight);
+		if (pcnet32_tx(dev)) {
 			/* reset the chip to clear the error condition, then restart */
 			lp->a.reset(ioaddr);
-			lp->a.write_csr(ioaddr, 4, 0x0915);
-			pcnet32_restart(dev, 0x0002);
+			lp->a.write_csr(ioaddr, CSR4, 0x0915);
+			pcnet32_restart(dev, CSR0_START);
 			netif_wake_queue(dev);
 		}
+#endif
+		csr0 = lp->a.read_csr(ioaddr, CSR0);
 	}
 
-	/* Set interrupt enable. */
-	lp->a.write_csr(ioaddr, 0, 0x0040);
-	lp->a.write_rap(ioaddr, rap);
+#ifndef CONFIG_PCNET32_NAPI
+	/*Set interrupt enable. */
+	lp->a.write_csr(ioaddr, CSR0, CSR0_INTEN);
+#endif
 
 	if (netif_msg_intr(lp))
 		printk(KERN_DEBUG "%s: exiting interrupt, csr0=%#4.4x.\n",
-		       dev->name, lp->a.read_csr(ioaddr, 0));
+		       dev->name, lp->a.read_csr(ioaddr, CSR0));
 
 	spin_unlock(&lp->lock);
 
-	return IRQ_HANDLED;
-}
-
-static int pcnet32_rx(struct net_device *dev)
-{
-	struct pcnet32_private *lp = dev->priv;
-	int entry = lp->cur_rx & lp->rx_mod_mask;
-	int boguscnt = lp->rx_ring_size / 2;
-
-	/* If we own the next entry, it's a new packet. Send it up. */
-	while ((short)le16_to_cpu(lp->rx_ring[entry].status) >= 0) {
-		int status = (short)le16_to_cpu(lp->rx_ring[entry].status) >> 8;
-
-		if (status != 0x03) {	/* There was an error. */
-			/*
-			 * There is a tricky error noted by John Murphy,
-			 * <[email-masked]> to Russ Nelson: Even with full-sized
-			 * buffers it's possible for a jabber packet to use two
-			 * buffers, with only the last correctly noting the error.
-			 */
-			if (status & 0x01)	/* Only count a general error at the */
-				lp->stats.rx_errors++;	/* end of a packet. */
-			if (status & 0x20)
-				lp->stats.rx_frame_errors++;
-			if (status & 0x10)
-				lp->stats.rx_over_errors++;
-			if (status & 0x08)
-				lp->stats.rx_crc_errors++;
-			if (status & 0x04)
-				lp->stats.rx_fifo_errors++;
-			lp->rx_ring[entry].status &= le16_to_cpu(0x03ff);
-		} else {
-			/* Malloc up new buffer, compatible with net-2e. */
-			short pkt_len =
-			    (le32_to_cpu(lp->rx_ring[entry].msg_length) & 0xfff)
-			    - 4;
-			struct sk_buff *skb;
-
-			/* Discard oversize frames. */
-			if (unlikely(pkt_len > PKT_BUF_SZ - 2)) {
-				if (netif_msg_drv(lp))
-					printk(KERN_ERR
-					       "%s: Impossible packet size %d!\n",
-					       dev->name, pkt_len);
-				lp->stats.rx_errors++;
-			} else if (pkt_len < 60) {
-				if (netif_msg_rx_err(lp))
-					printk(KERN_ERR "%s: Runt packet!\n",
-					       dev->name);
-				lp->stats.rx_errors++;
-			} else {
-				int rx_in_place = 0;
-
-				if (pkt_len > rx_copybreak) {
-					struct sk_buff *newskb;
-
-					if ((newskb =
-					     dev_alloc_skb(PKT_BUF_SZ))) {
-						skb_reserve(newskb, 2);
-						skb = lp->rx_skbuff[entry];
-						pci_unmap_single(lp->pci_dev,
-								 lp->
-								 rx_dma_addr
-								 [entry],
-								 PKT_BUF_SZ - 2,
-								 PCI_DMA_FROMDEVICE);
-						skb_put(skb, pkt_len);
-						lp->rx_skbuff[entry] = newskb;
-						newskb->dev = dev;
-						lp->rx_dma_addr[entry] =
-						    pci_map_single(lp->pci_dev,
-								   newskb->data,
-								   PKT_BUF_SZ -
-								   2,
-								   PCI_DMA_FROMDEVICE);
-						lp->rx_ring[entry].base =
-						    le32_to_cpu(lp->
-								rx_dma_addr
-								[entry]);
-						rx_in_place = 1;
-					} else
-						skb = NULL;
-				} else {
-					skb = dev_alloc_skb(pkt_len + 2);
-				}
-
-				if (skb == NULL) {
-					int i;
-					if (netif_msg_drv(lp))
-						printk(KERN_ERR
-						       "%s: Memory squeeze, deferring packet.\n",
-						       dev->name);
-					for (i = 0; i < lp->rx_ring_size; i++)
-						if ((short)
-						    le16_to_cpu(lp->
-								rx_ring[(entry +
-									 i)
-									& lp->
-									rx_mod_mask].
-								status) < 0)
-							break;
-
-					if (i > lp->rx_ring_size - 2) {
-						lp->stats.rx_dropped++;
-						lp->rx_ring[entry].status |=
-						    le16_to_cpu(0x8000);
-						wmb();	/* Make sure adapter sees owner change */
-						lp->cur_rx++;
-					}
-					break;
-				}
-				skb->dev = dev;
-				if (!rx_in_place) {
-					skb_reserve(skb, 2);	/* 16 byte align */
-					skb_put(skb, pkt_len);	/* Make room */
-					pci_dma_sync_single_for_cpu(lp->pci_dev,
-								    lp->
-								    rx_dma_addr
-								    [entry],
-								    PKT_BUF_SZ -
-								    2,
-								    PCI_DMA_FROMDEVICE);
-					eth_copy_and_sum(skb,
-							 (unsigned char *)(lp->
-									   rx_skbuff
-									   [entry]->
-									   data),
-							 pkt_len, 0);
-					pci_dma_sync_single_for_device(lp->
-								       pci_dev,
-								       lp->
-								       rx_dma_addr
-								       [entry],
-								       PKT_BUF_SZ
-								       - 2,
-								       PCI_DMA_FROMDEVICE);
-				}
-				lp->stats.rx_bytes += skb->len;
-				skb->protocol = eth_type_trans(skb, dev);
-				netif_rx(skb);
-				dev->last_rx = jiffies;
-				lp->stats.rx_packets++;
-			}
-		}
-		/*
-		 * The docs say that the buffer length isn't touched, but Andrew Boyd
-		 * of QNX reports that some revs of the 79C965 clear it.
-		 */
-		lp->rx_ring[entry].buf_length = le16_to_cpu(2 - PKT_BUF_SZ);
-		wmb();		/* Make sure owner changes after all others are visible */
-		lp->rx_ring[entry].status |= le16_to_cpu(0x8000);
-		entry = (++lp->cur_rx) & lp->rx_mod_mask;
-		if (--boguscnt <= 0)
-			break;	/* don't stay in loop forever */
-	}
-
-	return 0;
+	return rc;
 }
 
 static int pcnet32_close(struct net_device *dev)
-- 
Don Fry
[email-masked]