/*
 *  linux/drivers/acorn/net/ether3.c
 *
 *  Copyright (C) 1995-2000 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * SEEQ nq8005 ethernet driver for Acorn/ANT Ether3 card
 *  for Acorn machines
 *
 * By Russell King, with some suggestions from borris@ant.co.uk
 *
 * Changelog:
 * 1.04 RMK     29/02/1996      Won't pass packets that are from our ethernet
 *                              address up to the higher levels - they're
 *                              silently ignored.  I/F can now be put into
 *                              multicast mode.  Receiver routine optimised.
 * 1.05 RMK     30/02/1996      Now claims interrupt at open when part of
 *                              the kernel rather than when a module.
 * 1.06 RMK     02/03/1996      Various code cleanups
 * 1.07 RMK     13/10/1996      Optimised interrupt routine and transmit
 *                              routines.
 * 1.08 RMK     14/10/1996      Fixed problem with too many packets,
 *                              prevented the kernel message about dropped
 *                              packets appearing too many times a second.
 *                              Now does not disable all IRQs, only the IRQ
 *                              used by this card.
 * 1.09 RMK     10/11/1996      Only enables TX irq when buffer space is low,
 *                              but we still service the TX queue if we get a
 *                              RX interrupt.
 * 1.10 RMK     15/07/1997      Fixed autoprobing of NQ8004.
 * 1.11 RMK     16/11/1997      Fixed autoprobing of NQ8005A.
 * 1.12 RMK     31/12/1997      Removed reference to dev_tint for Linux 2.1.
 *      RMK     27/06/1998      Changed asm/delay.h to linux/delay.h.
 * 1.13 RMK     29/06/1998      Fixed problem with transmission of packets.
 *                              Chip seems to have a bug in, whereby if the
 *                              packet starts two bytes from the end of the
 *                              buffer, it corrupts the receiver chain, and
 *                              never updates the transmit status correctly.
 * 1.14 RMK     07/01/1998      Added initial code for ETHERB addressing.
 * 1.15 RMK     30/04/1999      More fixes to the transmit routine for buggy
 *                              hardware.
 * 1.16 RMK     10/02/2000      Updated for 2.3.43
 * 1.17 RMK     13/05/2000      Updated for 2.3.99-pre8
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/delay.h>

#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/ecard.h>
#include <asm/io.h>
#include <asm/irq.h>

static char version[] __initdata = "ether3 ethernet driver (c) 1995-2000 R.M.King v1.17\n";

#include "ether3.h"

static unsigned int net_debug = NET_DEBUG;
static const card_ids __init ether3_cids[] = {
        { MANU_ANT2, PROD_ANT_ETHER3 },
        { MANU_ANT,  PROD_ANT_ETHER3 },
        { MANU_ANT,  PROD_ANT_ETHERB },
        { 0xffff, 0xffff }
};

static void     ether3_setmulticastlist(struct net_device *dev);
static int      ether3_rx(struct net_device *dev, struct dev_priv *priv, unsigned int maxcnt);
static void     ether3_tx(struct net_device *dev, struct dev_priv *priv);
static int      ether3_open (struct net_device *dev);
static int      ether3_sendpacket (struct sk_buff *skb, struct net_device *dev);
static void     ether3_interrupt (int irq, void *dev_id, struct pt_regs *regs);
static int      ether3_close (struct net_device *dev);
static struct net_device_stats *ether3_getstats (struct net_device *dev);
static void     ether3_setmulticastlist (struct net_device *dev);
static void     ether3_timeout(struct net_device *dev);

#define BUS_16          2
#define BUS_8           1
#define BUS_UNKNOWN     0

/* --------------------------------------------------------------------------- */

typedef enum {
        buffer_write,
        buffer_read
} buffer_rw_t;

/*
 * ether3 read/write.  Slow things down a bit...
 * The SEEQ8005 doesn't like us writing to it's registers
 * too quickly.
 */
static inline void ether3_outb(int v, const int r)
{
        outb(v, r);
        udelay(1);
}

static inline void ether3_outw(int v, const int r)
{
        outw(v, r);
        udelay(1);
}
#define ether3_inb(r)           ({ unsigned int __v = inb((r)); udelay(1); __v; })
#define ether3_inw(r)           ({ unsigned int __v = inw((r)); udelay(1); __v; })

static int
ether3_setbuffer(struct net_device *dev, buffer_rw_t read, int start)
{
        struct dev_priv *priv = (struct dev_priv *)dev->priv;
        int timeout = 1000;

        ether3_outw(priv->regs.config1 | CFG1_LOCBUFMEM, REG_CONFIG1);
        ether3_outw(priv->regs.command | CMD_FIFOWRITE, REG_COMMAND);

        while ((ether3_inw(REG_STATUS) & STAT_FIFOEMPTY) == 0) {
                if (!timeout--) {
                        printk("%s: setbuffer broken\n", dev->name);
                        priv->broken = 1;
                        return 1;
                }
                udelay(1);
        }

        if (read == buffer_read) {
                ether3_outw(start, REG_DMAADDR);
                ether3_outw(priv->regs.command | CMD_FIFOREAD, REG_COMMAND);
        } else {
                ether3_outw(priv->regs.command | CMD_FIFOWRITE, REG_COMMAND);
                ether3_outw(start, REG_DMAADDR);
        }
        return 0;
}

/*
 * write data to the buffer memory
 */
#define ether3_writebuffer(dev,data,length)                     \
        outsw(REG_BUFWIN, (data), (length) >> 1)

#define ether3_writeword(dev,data)                              \
        outw((data), REG_BUFWIN)

#define ether3_writelong(dev,data)      {                       \
        unsigned long reg_bufwin = REG_BUFWIN;                  \
        outw((data), reg_bufwin);                               \
        outw((data) >> 16, reg_bufwin);                         \
}

/*
 * read data from the buffer memory
 */
#define ether3_readbuffer(dev,data,length)                      \
        insw(REG_BUFWIN, (data), (length) >> 1)

#define ether3_readword(dev)                                    \
        inw(REG_BUFWIN)

#define ether3_readlong(dev)                                    \
        inw(REG_BUFWIN) | (inw(REG_BUFWIN) << 16)

/*
 * Switch LED off...
 */
static void
ether3_ledoff(unsigned long data)
{
        struct net_device *dev = (struct net_device *)data;
        struct dev_priv *priv = (struct dev_priv *)dev->priv;
        ether3_outw(priv->regs.config2 |= CFG2_CTRLO, REG_CONFIG2);
}

/*
 * switch LED on...
 */
static inline void
ether3_ledon(struct net_device *dev, struct dev_priv *priv)
{
        del_timer(&priv->timer);
        priv->timer.expires = jiffies + HZ / 50; /* leave on for 1/50th second */
        priv->timer.data = (unsigned long)dev;
        priv->timer.function = ether3_ledoff;
        add_timer(&priv->timer);
        if (priv->regs.config2 & CFG2_CTRLO)
                ether3_outw(priv->regs.config2 &= ~CFG2_CTRLO, REG_CONFIG2);
}

/*
 * Read the ethernet address string from the on board rom.
 * This is an ascii string!!!
 */
static int __init
ether3_addr(char *addr, struct expansion_card *ec)
{
        struct in_chunk_dir cd;
        char *s;
        
        if (ecard_readchunk(&cd, ec, 0xf5, 0) && (s = strchr(cd.d.string, '('))) {
                int i;
                for (i = 0; i<6; i++) {
                        addr[i] = simple_strtoul(s + 1, &s, 0x10);
                        if (*s != (i==5?')' : ':' ))
                                break;
                }
                if (i == 6)
                        return 0;
        }
        /* I wonder if we should even let the user continue in this case
         *   - no, it would be better to disable the device
         */
        printk(KERN_ERR "ether3: Couldn't read a valid MAC address from card.\n");
        return -ENODEV;
}

/* --------------------------------------------------------------------------- */

static int __init
ether3_ramtest(struct net_device *dev, unsigned char byte)
{
        unsigned char *buffer = kmalloc(RX_END, GFP_KERNEL);
        int i,ret = 0;
        int max_errors = 4;
        int bad = -1;

        if (!buffer)
                return 1;

        memset(buffer, byte, RX_END);
        ether3_setbuffer(dev, buffer_write, 0);
        ether3_writebuffer(dev, buffer, TX_END);
        ether3_setbuffer(dev, buffer_write, RX_START);
        ether3_writebuffer(dev, buffer + RX_START, RX_LEN);
        memset(buffer, byte ^ 0xff, RX_END);
        ether3_setbuffer(dev, buffer_read, 0);
        ether3_readbuffer(dev, buffer, TX_END);
        ether3_setbuffer(dev, buffer_read, RX_START);
        ether3_readbuffer(dev, buffer + RX_START, RX_LEN);

        for (i = 0; i < RX_END; i++) {
                if (buffer[i] != byte) {
                        if (max_errors > 0 && bad != buffer[i]) {
                                printk("%s: RAM failed with (%02X instead of %02X) at 0x%04X",
                                       dev->name, buffer[i], byte, i);
                                ret = 2;
                                max_errors--;
                                bad = i;
                        }
                } else {
                        if (bad != -1) {
                                if (bad != i - 1)
                                        printk(" - 0x%04X\n", i - 1);
                                printk("\n");
                                bad = -1;
                        }
                }
        }
        if (bad != -1)
                printk(" - 0xffff\n");
        kfree(buffer);

        return ret;
}

/* ------------------------------------------------------------------------------- */

static int __init
ether3_init_2(struct net_device *dev)
{
        struct dev_priv *priv = (struct dev_priv *)dev->priv;
        int i;

        priv->regs.config1 = CFG1_RECVCOMPSTAT0|CFG1_DMABURST8;
        priv->regs.config2 = CFG2_CTRLO|CFG2_RECVCRC|CFG2_ERRENCRC;
        priv->regs.command = 0;

        /*
         * Set up our hardware address
         */
        ether3_outw(priv->regs.config1 | CFG1_BUFSELSTAT0, REG_CONFIG1);
        for (i = 0; i < 6; i++)
                ether3_outb(dev->dev_addr[i], REG_BUFWIN);

        if (dev->flags & IFF_PROMISC)
                priv->regs.config1 |= CFG1_RECVPROMISC;
        else if (dev->flags & IFF_MULTICAST)
                priv->regs.config1 |= CFG1_RECVSPECBRMULTI;
        else
                priv->regs.config1 |= CFG1_RECVSPECBROAD;

        /*
         * There is a problem with the NQ8005 in that it occasionally loses the
         * last two bytes.  To get round this problem, we receive the CRC as
         * well.  That way, if we do loose the last two, then it doesn't matter.
         */
        ether3_outw(priv->regs.config1 | CFG1_TRANSEND, REG_CONFIG1);
        ether3_outw((TX_END>>8) - 1, REG_BUFWIN);
        ether3_outw(priv->rx_head, REG_RECVPTR);
        ether3_outw(0, REG_TRANSMITPTR);
        ether3_outw(priv->rx_head >> 8, REG_RECVEND);
        ether3_outw(priv->regs.config2, REG_CONFIG2);
        ether3_outw(priv->regs.config1 | CFG1_LOCBUFMEM, REG_CONFIG1);
        ether3_outw(priv->regs.command, REG_COMMAND);

        i = ether3_ramtest(dev, 0x5A);
        if(i)
                return i;
        i = ether3_ramtest(dev, 0x1E);
        if(i)
                return i;

        ether3_setbuffer(dev, buffer_write, 0);
        ether3_writelong(dev, 0);
        return 0;
}

static void
ether3_init_for_open(struct net_device *dev)
{
        struct dev_priv *priv = (struct dev_priv *)dev->priv;
        int i;

        memset(&priv->stats, 0, sizeof(struct net_device_stats));

        /* Reset the chip */
        ether3_outw(CFG2_RESET, REG_CONFIG2);
        udelay(4);

        priv->regs.command = 0;
        ether3_outw(CMD_RXOFF|CMD_TXOFF, REG_COMMAND);
        while (ether3_inw(REG_STATUS) & (STAT_RXON|STAT_TXON));

        ether3_outw(priv->regs.config1 | CFG1_BUFSELSTAT0, REG_CONFIG1);
        for (i = 0; i < 6; i++)
                ether3_outb(dev->dev_addr[i], REG_BUFWIN);

        priv->tx_head   = 0;
        priv->tx_tail   = 0;
        priv->regs.config2 |= CFG2_CTRLO;
        priv->rx_head   = RX_START;

        ether3_outw(priv->regs.config1 | CFG1_TRANSEND, REG_CONFIG1);
        ether3_outw((TX_END>>8) - 1, REG_BUFWIN);
        ether3_outw(priv->rx_head, REG_RECVPTR);
        ether3_outw(priv->rx_head >> 8, REG_RECVEND);
        ether3_outw(0, REG_TRANSMITPTR);
        ether3_outw(priv->regs.config2, REG_CONFIG2);
        ether3_outw(priv->regs.config1 | CFG1_LOCBUFMEM, REG_CONFIG1);

        ether3_setbuffer(dev, buffer_write, 0);
        ether3_writelong(dev, 0);

        priv->regs.command = CMD_ENINTRX | CMD_ENINTTX;
        ether3_outw(priv->regs.command | CMD_RXON, REG_COMMAND);
}

static inline int
ether3_probe_bus_8(struct net_device *dev, int val)
{
        int write_low, write_high, read_low, read_high;

        write_low = val & 255;
        write_high = val >> 8;

        printk(KERN_DEBUG "ether3_probe: write8 [%02X:%02X]", write_high, write_low);

        ether3_outb(write_low, REG_RECVPTR);
        ether3_outb(write_high, REG_RECVPTR + 1);

        read_low = ether3_inb(REG_RECVPTR);
        read_high = ether3_inb(REG_RECVPTR + 1);

        printk(", read8 [%02X:%02X]\n", read_high, read_low);

        return read_low == write_low && read_high == write_high;
}

static inline int
ether3_probe_bus_16(struct net_device *dev, int val)
{
        int read_val;

        ether3_outw(val, REG_RECVPTR);
        read_val = ether3_inw(REG_RECVPTR);

        printk(KERN_DEBUG "ether3_probe: write16 [%04X], read16 [%04X]\n", val, read_val);

        return read_val == val;
}

/*
 * Open/initialize the board.  This is called (in the current kernel)
 * sometime after booting when the 'ifconfig' program is run.
 *
 * This routine should set everything up anew at each open, even
 * registers that "should" only need to be set once at boot, so that
 * there is non-reboot way to recover if something goes wrong.
 */
static int
ether3_open(struct net_device *dev)
{
        if (request_irq(dev->irq, ether3_interrupt, 0, "ether3", dev))
                return -EAGAIN;

        ether3_init_for_open(dev);

        netif_start_queue(dev);

        return 0;
}

/*
 * The inverse routine to ether3_open().
 */
static int
ether3_close(struct net_device *dev)
{
        struct dev_priv *priv = (struct dev_priv *)dev->priv;

        netif_stop_queue(dev);

        disable_irq(dev->irq);

        ether3_outw(CMD_RXOFF|CMD_TXOFF, REG_COMMAND);
        priv->regs.command = 0;
        while (ether3_inw(REG_STATUS) & (STAT_RXON|STAT_TXON));
        ether3_outb(0x80, REG_CONFIG2 + 1);
        ether3_outw(0, REG_COMMAND);

        free_irq(dev->irq, dev);

        return 0;
}

/*
 * Get the current statistics.  This may be called with the card open or
 * closed.
 */
static struct net_device_stats *ether3_getstats(struct net_device *dev)
{
        struct dev_priv *priv = (struct dev_priv *)dev->priv;
        return &priv->stats;
}

/*
 * Set or clear promiscuous/multicast mode filter for this adaptor.
 *
 * We don't attempt any packet filtering.  The card may have a SEEQ 8004
 * in which does not have the other ethernet address registers present...
 */
static void ether3_setmulticastlist(struct net_device *dev)
{
        struct dev_priv *priv = (struct dev_priv *)dev->priv;

        priv->regs.config1 &= ~CFG1_RECVPROMISC;

        if (dev->flags & IFF_PROMISC) {
                /* promiscuous mode */
                priv->regs.config1 |= CFG1_RECVPROMISC;
        } else if (dev->flags & IFF_ALLMULTI) {
                priv->regs.config1 |= CFG1_RECVSPECBRMULTI;
        } else
                priv->regs.config1 |= CFG1_RECVSPECBROAD;

        ether3_outw(priv->regs.config1 | CFG1_LOCBUFMEM, REG_CONFIG1);
}

static void
ether3_timeout(struct net_device *dev)
{
        struct dev_priv *priv = (struct dev_priv *)dev->priv;
        unsigned long flags;

        del_timer(&priv->timer);

        save_flags_cli(flags);
        printk(KERN_ERR "%s: transmit timed out, network cable problem?\n", dev->name);
        printk(KERN_ERR "%s: state: { status=%04X cfg1=%04X cfg2=%04X }\n", dev->name,
                ether3_inw(REG_STATUS), ether3_inw(REG_CONFIG1), ether3_inw(REG_CONFIG2));
        printk(KERN_ERR "%s: { rpr=%04X rea=%04X tpr=%04X }\n", dev->name,
                ether3_inw(REG_RECVPTR), ether3_inw(REG_RECVEND), ether3_inw(REG_TRANSMITPTR));
        printk(KERN_ERR "%s: tx head=%X tx tail=%X\n", dev->name,
                priv->tx_head, priv->tx_tail);
        ether3_setbuffer(dev, buffer_read, priv->tx_tail);
        printk(KERN_ERR "%s: packet status = %08X\n", dev->name, ether3_readlong(dev));
        restore_flags(flags);

        priv->regs.config2 |= CFG2_CTRLO;
        priv->stats.tx_errors += 1;
        ether3_outw(priv->regs.config2, REG_CONFIG2);
        priv->tx_head = priv->tx_tail = 0;

        netif_wake_queue(dev);
}

/*
 * Transmit a packet
 */
static int
ether3_sendpacket(struct sk_buff *skb, struct net_device *dev)
{
        struct dev_priv *priv = (struct dev_priv *)dev->priv;
        unsigned long flags;
        unsigned int length = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN;
        unsigned int ptr, next_ptr;

        length = (length + 1) & ~1;

        if (priv->broken) {
                dev_kfree_skb(skb);
                priv->stats.tx_dropped ++;
                netif_start_queue(dev);
                return 0;
        }

        next_ptr = (priv->tx_head + 1) & 15;

        save_flags_cli(flags);

        if (priv->tx_tail == next_ptr) {
                restore_flags(flags);
                return 1;       /* unable to queue */
        }

        dev->trans_start = jiffies;
        ptr              = 0x600 * priv->tx_head;
        priv->tx_head    = next_ptr;
        next_ptr        *= 0x600;

#define TXHDR_FLAGS (TXHDR_TRANSMIT|TXHDR_CHAINCONTINUE|TXHDR_DATAFOLLOWS|TXHDR_ENSUCCESS)

        ether3_setbuffer(dev, buffer_write, next_ptr);
        ether3_writelong(dev, 0);
        ether3_setbuffer(dev, buffer_write, ptr);
        ether3_writelong(dev, 0);
        ether3_writebuffer(dev, skb->data, length);
        ether3_writeword(dev, htons(next_ptr));
        ether3_writeword(dev, TXHDR_CHAINCONTINUE >> 16);
        ether3_setbuffer(dev, buffer_write, ptr);
        ether3_writeword(dev, htons((ptr + length + 4)));
        ether3_writeword(dev, TXHDR_FLAGS >> 16);
        ether3_ledon(dev, priv);

        if (!(ether3_inw(REG_STATUS) & STAT_TXON)) {
                ether3_outw(ptr, REG_TRANSMITPTR);
                ether3_outw(priv->regs.command | CMD_TXON, REG_COMMAND);
        }

        next_ptr = (priv->tx_head + 1) & 15;
        restore_flags(flags);

        dev_kfree_skb(skb);

        if (priv->tx_tail == next_ptr)
                netif_stop_queue(dev);

        return 0;
}

static void
ether3_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
        struct net_device *dev = (struct net_device *)dev_id;
        struct dev_priv *priv;
        unsigned int status;

#if NET_DEBUG > 1
        if(net_debug & DEBUG_INT)
                printk("eth3irq: %d ", irq);
#endif

        priv = (struct dev_priv *)dev->priv;

        status = ether3_inw(REG_STATUS);

        if (status & STAT_INTRX) {
                ether3_outw(CMD_ACKINTRX | priv->regs.command, REG_COMMAND);
                ether3_rx(dev, priv, 12);
        }

        if (status & STAT_INTTX) {
                ether3_outw(CMD_ACKINTTX | priv->regs.command, REG_COMMAND);
                ether3_tx(dev, priv);
        }

#if NET_DEBUG > 1
        if(net_debug & DEBUG_INT)
                printk("done\n");
#endif
}

/*
 * If we have a good packet(s), get it/them out of the buffers.
 */
static int
ether3_rx(struct net_device *dev, struct dev_priv *priv, unsigned int maxcnt)
{
        unsigned int next_ptr = priv->rx_head, received = 0;
        ether3_ledon(dev, priv);

        do {
                unsigned int this_ptr, status;
                unsigned char addrs[16];

                /*
                 * read the first 16 bytes from the buffer.
                 * This contains the status bytes etc and ethernet addresses,
                 * and we also check the source ethernet address to see if
                 * it originated from us.
                 */
                {
                        unsigned int temp_ptr;
                        ether3_setbuffer(dev, buffer_read, next_ptr);
                        temp_ptr = ether3_readword(dev);
                        status = ether3_readword(dev);
                        if ((status & (RXSTAT_DONE | RXHDR_CHAINCONTINUE | RXHDR_RECEIVE)) !=
                                (RXSTAT_DONE | RXHDR_CHAINCONTINUE) || !temp_ptr)
                                break;

                        this_ptr = next_ptr + 4;
                        next_ptr = ntohs(temp_ptr);
                }
                ether3_setbuffer(dev, buffer_read, this_ptr);
                ether3_readbuffer(dev, addrs+2, 12);

if (next_ptr < RX_START || next_ptr >= RX_END) {
 int i;
 printk("%s: bad next pointer @%04X: ", dev->name, priv->rx_head);
 printk("%02X %02X %02X %02X ", next_ptr >> 8, next_ptr & 255, status & 255, status >> 8);
 for (i = 2; i < 14; i++)
   printk("%02X ", addrs[i]);
 printk("\n");
 next_ptr = priv->rx_head;
 break;
}
                /*
                 * ignore our own packets...
                 */
                if (!(*(unsigned long *)&dev->dev_addr[0] ^ *(unsigned long *)&addrs[2+6]) &&
                    !(*(unsigned short *)&dev->dev_addr[4] ^ *(unsigned short *)&addrs[2+10])) {
                        maxcnt ++; /* compensate for loopedback packet */
                        ether3_outw(next_ptr >> 8, REG_RECVEND);
                } else
                if (!(status & (RXSTAT_OVERSIZE|RXSTAT_CRCERROR|RXSTAT_DRIBBLEERROR|RXSTAT_SHORTPACKET))) {
                        unsigned int length = next_ptr - this_ptr;
                        struct sk_buff *skb;

                        if (next_ptr <= this_ptr)
                                length += RX_END - RX_START;

                        skb = dev_alloc_skb(length + 2);
                        if (skb) {
                                unsigned char *buf;

                                skb->dev = dev;
                                skb_reserve(skb, 2);
                                buf = skb_put(skb, length);
                                ether3_readbuffer(dev, buf + 12, length - 12);
                                ether3_outw(next_ptr >> 8, REG_RECVEND);
                                *(unsigned short *)(buf + 0)    = *(unsigned short *)(addrs + 2);
                                *(unsigned long *)(buf + 2)     = *(unsigned long *)(addrs + 4);
                                *(unsigned long *)(buf + 6)     = *(unsigned long *)(addrs + 8);
                                *(unsigned short *)(buf + 10)   = *(unsigned short *)(addrs + 12);
                                skb->protocol = eth_type_trans(skb, dev);
                                netif_rx(skb);
                                received ++;
                        } else
                                goto dropping;
                } else {
                        struct net_device_stats *stats = &priv->stats;
                        ether3_outw(next_ptr >> 8, REG_RECVEND);
                        if (status & RXSTAT_OVERSIZE)     stats->rx_over_errors ++;
                        if (status & RXSTAT_CRCERROR)     stats->rx_crc_errors ++;
                        if (status & RXSTAT_DRIBBLEERROR) stats->rx_fifo_errors ++;
                        if (status & RXSTAT_SHORTPACKET)  stats->rx_length_errors ++;
                        stats->rx_errors++;
                }
        }
        while (-- maxcnt);

done:
        priv->stats.rx_packets += received;
        priv->rx_head = next_ptr;
        /*
         * If rx went off line, then that means that the buffer may be full.  We
         * have dropped at least one packet.
         */
        if (!(ether3_inw(REG_STATUS) & STAT_RXON)) {
                priv->stats.rx_dropped ++;
                ether3_outw(next_ptr, REG_RECVPTR);
                ether3_outw(priv->regs.command | CMD_RXON, REG_COMMAND);
        }

        return maxcnt;

dropping:{
        static unsigned long last_warned;

        ether3_outw(next_ptr >> 8, REG_RECVEND);
        /*
         * Don't print this message too many times...
         */
        if (jiffies - last_warned > 30 * HZ) {
                last_warned = jiffies;
                printk("%s: memory squeeze, dropping packet.\n", dev->name);
        }
        priv->stats.rx_dropped ++;
        goto done;
        }
}

/*
 * Update stats for the transmitted packet(s)
 */
static void
ether3_tx(struct net_device *dev, struct dev_priv *priv)
{
        unsigned int tx_tail = priv->tx_tail;
        int max_work = 14;

        do {
                unsigned long status;

                /*
                 * Read the packet header
                 */
                ether3_setbuffer(dev, buffer_read, tx_tail * 0x600);
                status = ether3_readlong(dev);

                /*
                 * Check to see if this packet has been transmitted
                 */
                if ((status & (TXSTAT_DONE | TXHDR_TRANSMIT)) !=
                    (TXSTAT_DONE | TXHDR_TRANSMIT))
                        break;

                /*
                 * Update errors
                 */
                if (!(status & (TXSTAT_BABBLED | TXSTAT_16COLLISIONS)))
                        priv->stats.tx_packets++;
                else {
                        priv->stats.tx_errors ++;
                        if (status & TXSTAT_16COLLISIONS) priv->stats.collisions += 16;
                        if (status & TXSTAT_BABBLED) priv->stats.tx_fifo_errors ++;
                }

                tx_tail = (tx_tail + 1) & 15;
        } while (--max_work);

        if (priv->tx_tail != tx_tail) {
                priv->tx_tail = tx_tail;
                netif_wake_queue(dev);
        }
}

static void __init ether3_banner(void)
{
        static unsigned version_printed = 0;

        if (net_debug && version_printed++ == 0)
                printk(KERN_INFO "%s", version);
}

static const char * __init
ether3_get_dev(struct net_device *dev, struct expansion_card *ec)
{
        const char *name = "ether3";
        dev->base_addr = ecard_address(ec, ECARD_MEMC, 0);
        dev->irq = ec->irq;

        if (ec->cid.manufacturer == MANU_ANT &&
            ec->cid.product == PROD_ANT_ETHERB) {
                dev->base_addr += 0x200;
                name = "etherb";
        }

        ec->irqaddr = (volatile unsigned char *)ioaddr(dev->base_addr);
        ec->irqmask = 0xf0;

        if (ether3_addr(dev->dev_addr, ec))
                name = NULL;

        return name;
}

static struct net_device * __init ether3_init_one(struct expansion_card *ec)
{
        struct net_device *dev;
        struct dev_priv *priv;
        const char *name;
        int i, bus_type;

        ether3_banner();

        ecard_claim(ec);

        dev = init_etherdev(NULL, sizeof(struct dev_priv));
        if (!dev)
                goto out;

        SET_MODULE_OWNER(dev);

        name = ether3_get_dev(dev, ec);
        if (!name)
                goto free;

        /*
         * this will not fail - the nature of the bus ensures this
         */
        if (!request_region(dev->base_addr, 128, dev->name))
                goto free;

        priv = (struct dev_priv *) dev->priv;

        /* Reset card...
         */
        ether3_outb(0x80, REG_CONFIG2 + 1);
        bus_type = BUS_UNKNOWN;
        udelay(4);

        /* Test using Receive Pointer (16-bit register) to find out
         * how the ether3 is connected to the bus...
         */
        if (ether3_probe_bus_8(dev, 0x100) &&
            ether3_probe_bus_8(dev, 0x201))
                bus_type = BUS_8;

        if (bus_type == BUS_UNKNOWN &&
            ether3_probe_bus_16(dev, 0x101) &&
            ether3_probe_bus_16(dev, 0x201))
                bus_type = BUS_16;

        switch (bus_type) {
        case BUS_UNKNOWN:
                printk(KERN_ERR "%s: unable to identify bus width\n", dev->name);
                goto failed;

        case BUS_8:
                printk(KERN_ERR "%s: %s found, but is an unsupported "
                        "8-bit card\n", dev->name, name);
                goto failed;

        default:
                break;
        }

        printk("%s: %s in slot %d, ", dev->name, name, ec->slot_no);
        for (i = 0; i < 6; i++)
                printk("%2.2x%c", dev->dev_addr[i], i == 5 ? '\n' : ':');

        if (ether3_init_2(dev))
                goto failed;

        dev->open               = ether3_open;
        dev->stop               = ether3_close;
        dev->hard_start_xmit    = ether3_sendpacket;
        dev->get_stats          = ether3_getstats;
        dev->set_multicast_list = ether3_setmulticastlist;
        dev->tx_timeout         = ether3_timeout;
        dev->watchdog_timeo     = 5 * HZ / 100;
        return 0;

failed:
        release_region(dev->base_addr, 128);
free:
        unregister_netdev(dev);
        kfree(dev);
out:
        ecard_release(ec);
        return NULL;
}

static struct expansion_card    *e_card[MAX_ECARDS];
static struct net_device        *e_dev[MAX_ECARDS];

static int ether3_init(void)
{
        int i, ret = -ENODEV;

        ecard_startfind();

        for (i = 0; i < MAX_ECARDS; i++) {
                struct net_device *dev;
                struct expansion_card *ec;

                ec = ecard_find(0, ether3_cids);
                if (!ec)
                        break;

                dev = ether3_init_one(ec);
                if (!dev)
                        break;

                e_card[i] = ec;
                e_dev[i]  = dev;
                ret = 0;
        }

        return ret;
}

static void ether3_exit(void)
{
        int i;

        for (i = 0; i < MAX_ECARDS; i++) {
                if (e_dev[i]) {
                        unregister_netdev(e_dev[i]);
                        release_region(e_dev[i]->base_addr, 128);
                        kfree(e_dev[i]);
                        e_dev[i] = NULL;
                }
                if (e_card[i]) {
                        ecard_release(e_card[i]);
                        e_card[i] = NULL;
                }
        }
}

module_init(ether3_init);
module_exit(ether3_exit);

MODULE_LICENSE("GPL");