Contributors: 23
Author Tokens Token Proportion Commits Commit Proportion
Joe Perches 2467 63.48% 1 2.44%
Linus Torvalds (pre-git) 1223 31.47% 10 24.39%
Andrew Morton 51 1.31% 2 4.88%
Geert Uytterhoeven 47 1.21% 7 17.07%
Alan Cox 31 0.80% 1 2.44%
Linus Torvalds 13 0.33% 2 4.88%
Paulius Zaleckas 8 0.21% 1 2.44%
Randy Dunlap 7 0.18% 1 2.44%
Al Viro 6 0.15% 1 2.44%
Julia Lawall 5 0.13% 1 2.44%
Dave Jones 5 0.13% 1 2.44%
Michael S. Tsirkin 4 0.10% 1 2.44%
Pradeep A. Dalvi 3 0.08% 1 2.44%
Arnaldo Carvalho de Melo 3 0.08% 1 2.44%
Alexander Beregalov 2 0.05% 1 2.44%
Stephen Hemminger 2 0.05% 2 4.88%
Herbert Xu 2 0.05% 1 2.44%
Patrick McHardy 2 0.05% 1 2.44%
Arvind Yadav 1 0.03% 1 2.44%
Jiri Pirko 1 0.03% 1 2.44%
Jan Engelhardt 1 0.03% 1 2.44%
Adrian Bunk 1 0.03% 1 2.44%
Björn Helgaas 1 0.03% 1 2.44%
Total 3886 41 


/*
 *  Amiga Linux/m68k Ariadne Ethernet Driver
 *
 *  © Copyright 1995-2003 by Geert Uytterhoeven (geert@linux-m68k.org)
 *			     Peter De Schrijver (p2@mind.be)
 *
 *  ---------------------------------------------------------------------------
 *
 *  This program is based on
 *
 *	lance.c:	An AMD LANCE ethernet driver for linux.
 *			Written 1993-94 by Donald Becker.
 *
 *	Am79C960:	PCnet(tm)-ISA Single-Chip Ethernet Controller
 *			Advanced Micro Devices
 *			Publication #16907, Rev. B, Amendment/0, May 1994
 *
 *	MC68230:	Parallel Interface/Timer (PI/T)
 *			Motorola Semiconductors, December, 1983
 *
 *  ---------------------------------------------------------------------------
 *
 *  This file is subject to the terms and conditions of the GNU General Public
 *  License.  See the file COPYING in the main directory of the Linux
 *  distribution for more details.
 *
 *  ---------------------------------------------------------------------------
 *
 *  The Ariadne is a Zorro-II board made by Village Tronic. It contains:
 *
 *	- an Am79C960 PCnet-ISA Single-Chip Ethernet Controller with both
 *	  10BASE-2 (thin coax) and 10BASE-T (UTP) connectors
 *
 *	- an MC68230 Parallel Interface/Timer configured as 2 parallel ports
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
/*#define DEBUG*/

#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/interrupt.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/zorro.h>
#include <linux/bitops.h>

#include <asm/byteorder.h>
#include <asm/amigaints.h>
#include <asm/amigahw.h>
#include <asm/irq.h>

#include "ariadne.h"

#ifdef ARIADNE_DEBUG
int ariadne_debug = ARIADNE_DEBUG;
#else
int ariadne_debug = 1;
#endif

/* Macros to Fix Endianness problems */

/* Swap the Bytes in a WORD */
#define swapw(x)	(((x >> 8) & 0x00ff) | ((x << 8) & 0xff00))
/* Get the Low BYTE in a WORD */
#define lowb(x)		(x & 0xff)
/* Get the Swapped High WORD in a LONG */
#define swhighw(x)	((((x) >> 8) & 0xff00) | (((x) >> 24) & 0x00ff))
/* Get the Swapped Low WORD in a LONG */
#define swloww(x)	((((x) << 8) & 0xff00) | (((x) >> 8) & 0x00ff))

/* Transmit/Receive Ring Definitions */

#define TX_RING_SIZE	5
#define RX_RING_SIZE	16

#define PKT_BUF_SIZE	1520

/* Private Device Data */

struct ariadne_private {
	volatile struct TDRE *tx_ring[TX_RING_SIZE];
	volatile struct RDRE *rx_ring[RX_RING_SIZE];
	volatile u_short *tx_buff[TX_RING_SIZE];
	volatile u_short *rx_buff[RX_RING_SIZE];
	int cur_tx, cur_rx;		/* The next free ring entry */
	int dirty_tx;			/* The ring entries to be free()ed */
	char tx_full;
};

/* Structure Created in the Ariadne's RAM Buffer */

struct lancedata {
	struct TDRE tx_ring[TX_RING_SIZE];
	struct RDRE rx_ring[RX_RING_SIZE];
	u_short tx_buff[TX_RING_SIZE][PKT_BUF_SIZE / sizeof(u_short)];
	u_short rx_buff[RX_RING_SIZE][PKT_BUF_SIZE / sizeof(u_short)];
};

static void memcpyw(volatile u_short *dest, u_short *src, int len)
{
	while (len >= 2) {
		*(dest++) = *(src++);
		len -= 2;
	}
	if (len == 1)
		*dest = (*(u_char *)src) << 8;
}

static void ariadne_init_ring(struct net_device *dev)
{
	struct ariadne_private *priv = netdev_priv(dev);
	volatile struct lancedata *lancedata = (struct lancedata *)dev->mem_start;
	int i;

	netif_stop_queue(dev);

	priv->tx_full = 0;
	priv->cur_rx = priv->cur_tx = 0;
	priv->dirty_tx = 0;

	/* Set up TX Ring */
	for (i = 0; i < TX_RING_SIZE; i++) {
		volatile struct TDRE *t = &lancedata->tx_ring[i];
		t->TMD0 = swloww(ARIADNE_RAM +
				 offsetof(struct lancedata, tx_buff[i]));
		t->TMD1 = swhighw(ARIADNE_RAM +
				  offsetof(struct lancedata, tx_buff[i])) |
			TF_STP | TF_ENP;
		t->TMD2 = swapw((u_short)-PKT_BUF_SIZE);
		t->TMD3 = 0;
		priv->tx_ring[i] = &lancedata->tx_ring[i];
		priv->tx_buff[i] = lancedata->tx_buff[i];
		netdev_dbg(dev, "TX Entry %2d at %p, Buf at %p\n",
			   i, &lancedata->tx_ring[i], lancedata->tx_buff[i]);
	}

	/* Set up RX Ring */
	for (i = 0; i < RX_RING_SIZE; i++) {
		volatile struct RDRE *r = &lancedata->rx_ring[i];
		r->RMD0 = swloww(ARIADNE_RAM +
				 offsetof(struct lancedata, rx_buff[i]));
		r->RMD1 = swhighw(ARIADNE_RAM +
				  offsetof(struct lancedata, rx_buff[i])) |
			RF_OWN;
		r->RMD2 = swapw((u_short)-PKT_BUF_SIZE);
		r->RMD3 = 0x0000;
		priv->rx_ring[i] = &lancedata->rx_ring[i];
		priv->rx_buff[i] = lancedata->rx_buff[i];
		netdev_dbg(dev, "RX Entry %2d at %p, Buf at %p\n",
			   i, &lancedata->rx_ring[i], lancedata->rx_buff[i]);
	}
}

static int ariadne_rx(struct net_device *dev)
{
	struct ariadne_private *priv = netdev_priv(dev);
	int entry = priv->cur_rx % RX_RING_SIZE;
	int i;

	/* If we own the next entry, it's a new packet. Send it up */
	while (!(lowb(priv->rx_ring[entry]->RMD1) & RF_OWN)) {
		int status = lowb(priv->rx_ring[entry]->RMD1);

		if (status != (RF_STP | RF_ENP)) {	/* There was an error */
			/* There is a tricky error noted by
			 * John Murphy <murf@perftech.com> 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
			 */
			/* Only count a general error at the end of a packet */
			if (status & RF_ENP)
				dev->stats.rx_errors++;
			if (status & RF_FRAM)
				dev->stats.rx_frame_errors++;
			if (status & RF_OFLO)
				dev->stats.rx_over_errors++;
			if (status & RF_CRC)
				dev->stats.rx_crc_errors++;
			if (status & RF_BUFF)
				dev->stats.rx_fifo_errors++;
			priv->rx_ring[entry]->RMD1 &= 0xff00 | RF_STP | RF_ENP;
		} else {
			/* Malloc up new buffer, compatible with net-3 */
			short pkt_len = swapw(priv->rx_ring[entry]->RMD3);
			struct sk_buff *skb;

			skb = netdev_alloc_skb(dev, pkt_len + 2);
			if (skb == NULL) {
				for (i = 0; i < RX_RING_SIZE; i++)
					if (lowb(priv->rx_ring[(entry + i) % RX_RING_SIZE]->RMD1) & RF_OWN)
						break;

				if (i > RX_RING_SIZE - 2) {
					dev->stats.rx_dropped++;
					priv->rx_ring[entry]->RMD1 |= RF_OWN;
					priv->cur_rx++;
				}
				break;
			}


			skb_reserve(skb, 2);	/* 16 byte align */
			skb_put(skb, pkt_len);	/* Make room */
			skb_copy_to_linear_data(skb,
						(const void *)priv->rx_buff[entry],
						pkt_len);
			skb->protocol = eth_type_trans(skb, dev);
			netdev_dbg(dev, "RX pkt type 0x%04x from %pM to %pM data %p len %u\n",
				   ((u_short *)skb->data)[6],
				   skb->data + 6, skb->data,
				   skb->data, skb->len);

			netif_rx(skb);
			dev->stats.rx_packets++;
			dev->stats.rx_bytes += pkt_len;
		}

		priv->rx_ring[entry]->RMD1 |= RF_OWN;
		entry = (++priv->cur_rx) % RX_RING_SIZE;
	}

	priv->cur_rx = priv->cur_rx % RX_RING_SIZE;

	/* We should check that at least two ring entries are free.
	 * If not, we should free one and mark stats->rx_dropped++
	 */

	return 0;
}

static irqreturn_t ariadne_interrupt(int irq, void *data)
{
	struct net_device *dev = (struct net_device *)data;
	volatile struct Am79C960 *lance = (struct Am79C960 *)dev->base_addr;
	struct ariadne_private *priv;
	int csr0, boguscnt;
	int handled = 0;

	lance->RAP = CSR0;		/* PCnet-ISA Controller Status */

	if (!(lance->RDP & INTR))	/* Check if any interrupt has been */
		return IRQ_NONE;	/* generated by the board */

	priv = netdev_priv(dev);

	boguscnt = 10;
	while ((csr0 = lance->RDP) & (ERR | RINT | TINT) && --boguscnt >= 0) {
		/* Acknowledge all of the current interrupt sources ASAP */
		lance->RDP = csr0 & ~(INEA | TDMD | STOP | STRT | INIT);

#ifdef DEBUG
		if (ariadne_debug > 5) {
			netdev_dbg(dev, "interrupt  csr0=%#02x new csr=%#02x [",
				   csr0, lance->RDP);
			if (csr0 & INTR)
				pr_cont(" INTR");
			if (csr0 & INEA)
				pr_cont(" INEA");
			if (csr0 & RXON)
				pr_cont(" RXON");
			if (csr0 & TXON)
				pr_cont(" TXON");
			if (csr0 & TDMD)
				pr_cont(" TDMD");
			if (csr0 & STOP)
				pr_cont(" STOP");
			if (csr0 & STRT)
				pr_cont(" STRT");
			if (csr0 & INIT)
				pr_cont(" INIT");
			if (csr0 & ERR)
				pr_cont(" ERR");
			if (csr0 & BABL)
				pr_cont(" BABL");
			if (csr0 & CERR)
				pr_cont(" CERR");
			if (csr0 & MISS)
				pr_cont(" MISS");
			if (csr0 & MERR)
				pr_cont(" MERR");
			if (csr0 & RINT)
				pr_cont(" RINT");
			if (csr0 & TINT)
				pr_cont(" TINT");
			if (csr0 & IDON)
				pr_cont(" IDON");
			pr_cont(" ]\n");
		}
#endif

		if (csr0 & RINT) {	/* Rx interrupt */
			handled = 1;
			ariadne_rx(dev);
		}

		if (csr0 & TINT) {	/* Tx-done interrupt */
			int dirty_tx = priv->dirty_tx;

			handled = 1;
			while (dirty_tx < priv->cur_tx) {
				int entry = dirty_tx % TX_RING_SIZE;
				int status = lowb(priv->tx_ring[entry]->TMD1);

				if (status & TF_OWN)
					break;	/* It still hasn't been Txed */

				priv->tx_ring[entry]->TMD1 &= 0xff00;

				if (status & TF_ERR) {
					/* There was an major error, log it */
					int err_status = priv->tx_ring[entry]->TMD3;
					dev->stats.tx_errors++;
					if (err_status & EF_RTRY)
						dev->stats.tx_aborted_errors++;
					if (err_status & EF_LCAR)
						dev->stats.tx_carrier_errors++;
					if (err_status & EF_LCOL)
						dev->stats.tx_window_errors++;
					if (err_status & EF_UFLO) {
						/* Ackk!  On FIFO errors the Tx unit is turned off! */
						dev->stats.tx_fifo_errors++;
						/* Remove this verbosity later! */
						netdev_err(dev, "Tx FIFO error! Status %04x\n",
							   csr0);
						/* Restart the chip */
						lance->RDP = STRT;
					}
				} else {
					if (status & (TF_MORE | TF_ONE))
						dev->stats.collisions++;
					dev->stats.tx_packets++;
				}
				dirty_tx++;
			}

#ifndef final_version
			if (priv->cur_tx - dirty_tx >= TX_RING_SIZE) {
				netdev_err(dev, "out-of-sync dirty pointer, %d vs. %d, full=%d\n",
					   dirty_tx, priv->cur_tx,
					   priv->tx_full);
				dirty_tx += TX_RING_SIZE;
			}
#endif

			if (priv->tx_full && netif_queue_stopped(dev) &&
			    dirty_tx > priv->cur_tx - TX_RING_SIZE + 2) {
				/* The ring is no longer full */
				priv->tx_full = 0;
				netif_wake_queue(dev);
			}

			priv->dirty_tx = dirty_tx;
		}

		/* Log misc errors */
		if (csr0 & BABL) {
			handled = 1;
			dev->stats.tx_errors++;	/* Tx babble */
		}
		if (csr0 & MISS) {
			handled = 1;
			dev->stats.rx_errors++;	/* Missed a Rx frame */
		}
		if (csr0 & MERR) {
			handled = 1;
			netdev_err(dev, "Bus master arbitration failure, status %04x\n",
				   csr0);
			/* Restart the chip */
			lance->RDP = STRT;
		}
	}

	/* Clear any other interrupt, and set interrupt enable */
	lance->RAP = CSR0;		/* PCnet-ISA Controller Status */
	lance->RDP = INEA | BABL | CERR | MISS | MERR | IDON;

	if (ariadne_debug > 4)
		netdev_dbg(dev, "exiting interrupt, csr%d=%#04x\n",
			   lance->RAP, lance->RDP);

	return IRQ_RETVAL(handled);
}

static int ariadne_open(struct net_device *dev)
{
	volatile struct Am79C960 *lance = (struct Am79C960 *)dev->base_addr;
	u_short in;
	u_long version;
	int i;

	/* Reset the LANCE */
	in = lance->Reset;

	/* Stop the LANCE */
	lance->RAP = CSR0;		/* PCnet-ISA Controller Status */
	lance->RDP = STOP;

	/* Check the LANCE version */
	lance->RAP = CSR88;		/* Chip ID */
	version = swapw(lance->RDP);
	lance->RAP = CSR89;		/* Chip ID */
	version |= swapw(lance->RDP) << 16;
	if ((version & 0x00000fff) != 0x00000003) {
		pr_warn("Couldn't find AMD Ethernet Chip\n");
		return -EAGAIN;
	}
	if ((version & 0x0ffff000) != 0x00003000) {
		pr_warn("Couldn't find Am79C960 (Wrong part number = %ld)\n",
		       (version & 0x0ffff000) >> 12);
		return -EAGAIN;
	}

	netdev_dbg(dev, "Am79C960 (PCnet-ISA) Revision %ld\n",
		   (version & 0xf0000000) >> 28);

	ariadne_init_ring(dev);

	/* Miscellaneous Stuff */
	lance->RAP = CSR3;		/* Interrupt Masks and Deferral Control */
	lance->RDP = 0x0000;
	lance->RAP = CSR4;		/* Test and Features Control */
	lance->RDP = DPOLL | APAD_XMT | MFCOM | RCVCCOM | TXSTRTM | JABM;

	/* Set the Multicast Table */
	lance->RAP = CSR8;		/* Logical Address Filter, LADRF[15:0] */
	lance->RDP = 0x0000;
	lance->RAP = CSR9;		/* Logical Address Filter, LADRF[31:16] */
	lance->RDP = 0x0000;
	lance->RAP = CSR10;		/* Logical Address Filter, LADRF[47:32] */
	lance->RDP = 0x0000;
	lance->RAP = CSR11;		/* Logical Address Filter, LADRF[63:48] */
	lance->RDP = 0x0000;

	/* Set the Ethernet Hardware Address */
	lance->RAP = CSR12;		/* Physical Address Register, PADR[15:0] */
	lance->RDP = ((u_short *)&dev->dev_addr[0])[0];
	lance->RAP = CSR13;		/* Physical Address Register, PADR[31:16] */
	lance->RDP = ((u_short *)&dev->dev_addr[0])[1];
	lance->RAP = CSR14;		/* Physical Address Register, PADR[47:32] */
	lance->RDP = ((u_short *)&dev->dev_addr[0])[2];

	/* Set the Init Block Mode */
	lance->RAP = CSR15;		/* Mode Register */
	lance->RDP = 0x0000;

	/* Set the Transmit Descriptor Ring Pointer */
	lance->RAP = CSR30;		/* Base Address of Transmit Ring */
	lance->RDP = swloww(ARIADNE_RAM + offsetof(struct lancedata, tx_ring));
	lance->RAP = CSR31;		/* Base Address of transmit Ring */
	lance->RDP = swhighw(ARIADNE_RAM + offsetof(struct lancedata, tx_ring));

	/* Set the Receive Descriptor Ring Pointer */
	lance->RAP = CSR24;		/* Base Address of Receive Ring */
	lance->RDP = swloww(ARIADNE_RAM + offsetof(struct lancedata, rx_ring));
	lance->RAP = CSR25;		/* Base Address of Receive Ring */
	lance->RDP = swhighw(ARIADNE_RAM + offsetof(struct lancedata, rx_ring));

	/* Set the Number of RX and TX Ring Entries */
	lance->RAP = CSR76;		/* Receive Ring Length */
	lance->RDP = swapw(((u_short)-RX_RING_SIZE));
	lance->RAP = CSR78;		/* Transmit Ring Length */
	lance->RDP = swapw(((u_short)-TX_RING_SIZE));

	/* Enable Media Interface Port Auto Select (10BASE-2/10BASE-T) */
	lance->RAP = ISACSR2;		/* Miscellaneous Configuration */
	lance->IDP = ASEL;

	/* LED Control */
	lance->RAP = ISACSR5;		/* LED1 Status */
	lance->IDP = PSE|XMTE;
	lance->RAP = ISACSR6;	/* LED2 Status */
	lance->IDP = PSE|COLE;
	lance->RAP = ISACSR7;	/* LED3 Status */
	lance->IDP = PSE|RCVE;

	netif_start_queue(dev);

	i = request_irq(IRQ_AMIGA_PORTS, ariadne_interrupt, IRQF_SHARED,
			dev->name, dev);
	if (i)
		return i;

	lance->RAP = CSR0;		/* PCnet-ISA Controller Status */
	lance->RDP = INEA | STRT;

	return 0;
}

static int ariadne_close(struct net_device *dev)
{
	volatile struct Am79C960 *lance = (struct Am79C960 *)dev->base_addr;

	netif_stop_queue(dev);

	lance->RAP = CSR112;		/* Missed Frame Count */
	dev->stats.rx_missed_errors = swapw(lance->RDP);
	lance->RAP = CSR0;		/* PCnet-ISA Controller Status */

	if (ariadne_debug > 1) {
		netdev_dbg(dev, "Shutting down ethercard, status was %02x\n",
			   lance->RDP);
		netdev_dbg(dev, "%lu packets missed\n",
			   dev->stats.rx_missed_errors);
	}

	/* We stop the LANCE here -- it occasionally polls memory if we don't */
	lance->RDP = STOP;

	free_irq(IRQ_AMIGA_PORTS, dev);

	return 0;
}

static inline void ariadne_reset(struct net_device *dev)
{
	volatile struct Am79C960 *lance = (struct Am79C960 *)dev->base_addr;

	lance->RAP = CSR0;	/* PCnet-ISA Controller Status */
	lance->RDP = STOP;
	ariadne_init_ring(dev);
	lance->RDP = INEA | STRT;
	netif_start_queue(dev);
}

static void ariadne_tx_timeout(struct net_device *dev, unsigned int txqueue)
{
	volatile struct Am79C960 *lance = (struct Am79C960 *)dev->base_addr;

	netdev_err(dev, "transmit timed out, status %04x, resetting\n",
		   lance->RDP);
	ariadne_reset(dev);
	netif_wake_queue(dev);
}

static netdev_tx_t ariadne_start_xmit(struct sk_buff *skb,
				      struct net_device *dev)
{
	struct ariadne_private *priv = netdev_priv(dev);
	volatile struct Am79C960 *lance = (struct Am79C960 *)dev->base_addr;
	int entry;
	unsigned long flags;
	int len = skb->len;

#if 0
	if (ariadne_debug > 3) {
		lance->RAP = CSR0;	/* PCnet-ISA Controller Status */
		netdev_dbg(dev, "%s: csr0 %04x\n", __func__, lance->RDP);
		lance->RDP = 0x0000;
	}
#endif

	/* FIXME: is the 79C960 new enough to do its own padding right ? */
	if (skb->len < ETH_ZLEN) {
		if (skb_padto(skb, ETH_ZLEN))
			return NETDEV_TX_OK;
		len = ETH_ZLEN;
	}

	/* Fill in a Tx ring entry */

	netdev_dbg(dev, "TX pkt type 0x%04x from %pM to %pM data %p len %u\n",
		   ((u_short *)skb->data)[6],
		   skb->data + 6, skb->data,
		   skb->data, skb->len);

	local_irq_save(flags);

	entry = priv->cur_tx % TX_RING_SIZE;

	/* Caution: the write order is important here, set the base address with
	   the "ownership" bits last */

	priv->tx_ring[entry]->TMD2 = swapw((u_short)-skb->len);
	priv->tx_ring[entry]->TMD3 = 0x0000;
	memcpyw(priv->tx_buff[entry], (u_short *)skb->data, len);

#ifdef DEBUG
	print_hex_dump(KERN_DEBUG, "tx_buff: ", DUMP_PREFIX_OFFSET, 16, 1,
		       (void *)priv->tx_buff[entry],
		       skb->len > 64 ? 64 : skb->len, true);
#endif

	priv->tx_ring[entry]->TMD1 = (priv->tx_ring[entry]->TMD1 & 0xff00)
		| TF_OWN | TF_STP | TF_ENP;

	dev_kfree_skb(skb);

	priv->cur_tx++;
	if ((priv->cur_tx >= TX_RING_SIZE) &&
	    (priv->dirty_tx >= TX_RING_SIZE)) {

		netdev_dbg(dev, "*** Subtracting TX_RING_SIZE from cur_tx (%d) and dirty_tx (%d)\n",
			   priv->cur_tx, priv->dirty_tx);

		priv->cur_tx -= TX_RING_SIZE;
		priv->dirty_tx -= TX_RING_SIZE;
	}
	dev->stats.tx_bytes += len;

	/* Trigger an immediate send poll */
	lance->RAP = CSR0;		/* PCnet-ISA Controller Status */
	lance->RDP = INEA | TDMD;

	if (lowb(priv->tx_ring[(entry + 1) % TX_RING_SIZE]->TMD1) != 0) {
		netif_stop_queue(dev);
		priv->tx_full = 1;
	}
	local_irq_restore(flags);

	return NETDEV_TX_OK;
}

static struct net_device_stats *ariadne_get_stats(struct net_device *dev)
{
	volatile struct Am79C960 *lance = (struct Am79C960 *)dev->base_addr;
	short saved_addr;
	unsigned long flags;

	local_irq_save(flags);
	saved_addr = lance->RAP;
	lance->RAP = CSR112;		/* Missed Frame Count */
	dev->stats.rx_missed_errors = swapw(lance->RDP);
	lance->RAP = saved_addr;
	local_irq_restore(flags);

	return &dev->stats;
}

/* Set or clear the multicast filter for this adaptor.
 * num_addrs == -1	Promiscuous mode, receive all packets
 * num_addrs == 0	Normal mode, clear multicast list
 * num_addrs > 0	Multicast mode, receive normal and MC packets,
 * 			and do best-effort filtering.
 */
static void set_multicast_list(struct net_device *dev)
{
	volatile struct Am79C960 *lance = (struct Am79C960 *)dev->base_addr;

	if (!netif_running(dev))
		return;

	netif_stop_queue(dev);

	/* We take the simple way out and always enable promiscuous mode */
	lance->RAP = CSR0;		/* PCnet-ISA Controller Status */
	lance->RDP = STOP;		/* Temporarily stop the lance */
	ariadne_init_ring(dev);

	if (dev->flags & IFF_PROMISC) {
		lance->RAP = CSR15;	/* Mode Register */
		lance->RDP = PROM;	/* Set promiscuous mode */
	} else {
		short multicast_table[4];
		int num_addrs = netdev_mc_count(dev);
		int i;
		/* We don't use the multicast table,
		 * but rely on upper-layer filtering
		 */
		memset(multicast_table, (num_addrs == 0) ? 0 : -1,
		       sizeof(multicast_table));
		for (i = 0; i < 4; i++) {
			lance->RAP = CSR8 + (i << 8);
					/* Logical Address Filter */
			lance->RDP = swapw(multicast_table[i]);
		}
		lance->RAP = CSR15;	/* Mode Register */
		lance->RDP = 0x0000;	/* Unset promiscuous mode */
	}

	lance->RAP = CSR0;		/* PCnet-ISA Controller Status */
	lance->RDP = INEA | STRT | IDON;/* Resume normal operation */

	netif_wake_queue(dev);
}


static void ariadne_remove_one(struct zorro_dev *z)
{
	struct net_device *dev = zorro_get_drvdata(z);

	unregister_netdev(dev);
	release_mem_region(ZTWO_PADDR(dev->base_addr), sizeof(struct Am79C960));
	release_mem_region(ZTWO_PADDR(dev->mem_start), ARIADNE_RAM_SIZE);
	free_netdev(dev);
}

static const struct zorro_device_id ariadne_zorro_tbl[] = {
	{ ZORRO_PROD_VILLAGE_TRONIC_ARIADNE },
	{ 0 }
};
MODULE_DEVICE_TABLE(zorro, ariadne_zorro_tbl);

static const struct net_device_ops ariadne_netdev_ops = {
	.ndo_open		= ariadne_open,
	.ndo_stop		= ariadne_close,
	.ndo_start_xmit		= ariadne_start_xmit,
	.ndo_tx_timeout		= ariadne_tx_timeout,
	.ndo_get_stats		= ariadne_get_stats,
	.ndo_set_rx_mode	= set_multicast_list,
	.ndo_validate_addr	= eth_validate_addr,
	.ndo_set_mac_address	= eth_mac_addr,
};

static int ariadne_init_one(struct zorro_dev *z,
			    const struct zorro_device_id *ent)
{
	unsigned long board = z->resource.start;
	unsigned long base_addr = board + ARIADNE_LANCE;
	unsigned long mem_start = board + ARIADNE_RAM;
	struct resource *r1, *r2;
	struct net_device *dev;
	u32 serial;
	int err;

	r1 = request_mem_region(base_addr, sizeof(struct Am79C960), "Am79C960");
	if (!r1)
		return -EBUSY;
	r2 = request_mem_region(mem_start, ARIADNE_RAM_SIZE, "RAM");
	if (!r2) {
		release_mem_region(base_addr, sizeof(struct Am79C960));
		return -EBUSY;
	}

	dev = alloc_etherdev(sizeof(struct ariadne_private));
	if (dev == NULL) {
		release_mem_region(base_addr, sizeof(struct Am79C960));
		release_mem_region(mem_start, ARIADNE_RAM_SIZE);
		return -ENOMEM;
	}

	r1->name = dev->name;
	r2->name = dev->name;

	serial = be32_to_cpu(z->rom.er_SerialNumber);
	dev->dev_addr[0] = 0x00;
	dev->dev_addr[1] = 0x60;
	dev->dev_addr[2] = 0x30;
	dev->dev_addr[3] = (serial >> 16) & 0xff;
	dev->dev_addr[4] = (serial >> 8) & 0xff;
	dev->dev_addr[5] = serial & 0xff;
	dev->base_addr = (unsigned long)ZTWO_VADDR(base_addr);
	dev->mem_start = (unsigned long)ZTWO_VADDR(mem_start);
	dev->mem_end = dev->mem_start + ARIADNE_RAM_SIZE;

	dev->netdev_ops = &ariadne_netdev_ops;
	dev->watchdog_timeo = 5 * HZ;

	err = register_netdev(dev);
	if (err) {
		release_mem_region(base_addr, sizeof(struct Am79C960));
		release_mem_region(mem_start, ARIADNE_RAM_SIZE);
		free_netdev(dev);
		return err;
	}
	zorro_set_drvdata(z, dev);

	netdev_info(dev, "Ariadne at 0x%08lx, Ethernet Address %pM\n",
		    board, dev->dev_addr);

	return 0;
}

static struct zorro_driver ariadne_driver = {
	.name		= "ariadne",
	.id_table	= ariadne_zorro_tbl,
	.probe		= ariadne_init_one,
	.remove		= ariadne_remove_one,
};

static int __init ariadne_init_module(void)
{
	return zorro_register_driver(&ariadne_driver);
}

static void __exit ariadne_cleanup_module(void)
{
	zorro_unregister_driver(&ariadne_driver);
}

module_init(ariadne_init_module);
module_exit(ariadne_cleanup_module);

MODULE_LICENSE("GPL");