/* Intel EtherExpress 16 device driver for Linux
 *
 * Written by John Sullivan, 1995
 *  based on original code by Donald Becker, with changes by
 *  Alan Cox and Pauline Middelink.
 *
 * Support for 8-bit mode by Zoltan Szilagyi <zoltans@cs.arizona.edu>
 *
 * Many modifications, and currently maintained, by
 *  Philip Blundell <philb@gnu.org>
 * Added the Compaq LTE  Alan Cox <alan@lxorguk.ukuu.org.uk>
 * Added MCA support Adam Fritzler
 *
 * Note - this driver is experimental still - it has problems on faster
 * machines. Someone needs to sit down and go through it line by line with
 * a databook...
 */

/* The EtherExpress 16 is a fairly simple card, based on a shared-memory
 * design using the i82586 Ethernet coprocessor.  It bears no relationship,
 * as far as I know, to the similarly-named "EtherExpress Pro" range.
 *
 * Historically, Linux support for these cards has been very bad.  However,
 * things seem to be getting better slowly.
 */

/* If your card is confused about what sort of interface it has (eg it
 * persistently reports "10baseT" when none is fitted), running 'SOFTSET /BART'
 * or 'SOFTSET /LISA' from DOS seems to help.
 */

/* Here's the scoop on memory mapping.
 *
 * There are three ways to access EtherExpress card memory: either using the
 * shared-memory mapping, or using PIO through the dataport, or using PIO
 * through the "shadow memory" ports.
 *
 * The shadow memory system works by having the card map some of its memory
 * as follows:
 *
 * (the low five bits of the SMPTR are ignored)
 *
 *  base+0x4000..400f      memory at SMPTR+0..15
 *  base+0x8000..800f      memory at SMPTR+16..31
 *  base+0xc000..c007      dubious stuff (memory at SMPTR+16..23 apparently)
 *  base+0xc008..c00f      memory at 0x0008..0x000f
 *
 * This last set (the one at c008) is particularly handy because the SCB
 * lives at 0x0008.  So that set of ports gives us easy random access to data
 * in the SCB without having to mess around setting up pointers and the like.
 * We always use this method to access the SCB (via the scb_xx() functions).
 *
 * Dataport access works by aiming the appropriate (read or write) pointer
 * at the first address you're interested in, and then reading or writing from
 * the dataport.  The pointers auto-increment after each transfer.  We use
 * this for data transfer.
 *
 * We don't use the shared-memory system because it allegedly doesn't work on
 * all cards, and because it's a bit more prone to go wrong (it's one more
 * thing to configure...).
 */

/* Known bugs:
 *
 * - The card seems to want to give us two interrupts every time something
 *   happens, where just one would be better.
 */

/*
 *
 * Note by Zoltan Szilagyi 10-12-96:
 *
 * I've succeeded in eliminating the "CU wedged" messages, and hence the
 * lockups, which were only occurring with cards running in 8-bit mode ("force
 * 8-bit operation" in Intel's SoftSet utility). This version of the driver
 * sets the 82586 and the ASIC to 8-bit mode at startup; it also stops the
 * CU before submitting a packet for transmission, and then restarts it as soon
 * as the process of handing the packet is complete. This is definitely an
 * unnecessary slowdown if the card is running in 16-bit mode; therefore one
 * should detect 16-bit vs 8-bit mode from the EEPROM settings and act
 * accordingly. In 8-bit mode with this bugfix I'm getting about 150 K/s for
 * ftp's, which is significantly better than I get in DOS, so the overhead of
 * stopping and restarting the CU with each transmit is not prohibitive in
 * practice.
 *
 * Update by David Woodhouse 11/5/99:
 *
 * I've seen "CU wedged" messages in 16-bit mode, on the Alpha architecture.
 * I assume that this is because 16-bit accesses are actually handled as two
 * 8-bit accesses.
 */

#ifdef __alpha__
#define LOCKUP16 1
#endif
#ifndef LOCKUP16
#define LOCKUP16 0
#endif

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/mca-legacy.h>
#include <linux/spinlock.h>
#include <linux/bitops.h>
#include <linux/jiffies.h>

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

#ifndef NET_DEBUG
#define NET_DEBUG 4
#endif

#include "eexpress.h"

#define EEXP_IO_EXTENT  16

/*
 * Private data declarations
 */

struct net_local
{
        unsigned long last_tx;       /* jiffies when last transmit started */
        unsigned long init_time;     /* jiffies when eexp_hw_init586 called */
        unsigned short rx_first;     /* first rx buf, same as RX_BUF_START */
        unsigned short rx_last;      /* last rx buf */
        unsigned short rx_ptr;       /* first rx buf to look at */
        unsigned short tx_head;      /* next free tx buf */
        unsigned short tx_reap;      /* first in-use tx buf */
        unsigned short tx_tail;      /* previous tx buf to tx_head */
        unsigned short tx_link;      /* last known-executing tx buf */
        unsigned short last_tx_restart;   /* set to tx_link when we
                                             restart the CU */
        unsigned char started;
        unsigned short rx_buf_start;
        unsigned short rx_buf_end;
        unsigned short num_tx_bufs;
        unsigned short num_rx_bufs;
        unsigned char width;         /* 0 for 16bit, 1 for 8bit */
        unsigned char was_promisc;
        unsigned char old_mc_count;
        spinlock_t lock;
};

/* This is the code and data that is downloaded to the EtherExpress card's
 * memory at boot time.
 */

static unsigned short start_code[] = {
/* 0x0000 */
        0x0001,                 /* ISCP: busy - cleared after reset */
        0x0008,0x0000,0x0000,   /* offset,address (lo,hi) of SCB */

        0x0000,0x0000,          /* SCB: status, commands */
        0x0000,0x0000,          /* links to first command block,
                                   first receive descriptor */
        0x0000,0x0000,          /* CRC error, alignment error counts */
        0x0000,0x0000,          /* out of resources, overrun error counts */

        0x0000,0x0000,          /* pad */
        0x0000,0x0000,

/* 0x20 -- start of 82586 CU program */
#define CONF_LINK 0x20
        0x0000,Cmd_Config,
        0x0032,                 /* link to next command */
        0x080c,                 /* 12 bytes follow : fifo threshold=8 */
        0x2e40,                 /* don't rx bad frames
                                 * SRDY/ARDY => ext. sync. : preamble len=8
                                 * take addresses from data buffers
                                 * 6 bytes/address
                                 */
        0x6000,                 /* default backoff method & priority
                                 * interframe spacing = 0x60 */
        0xf200,                 /* slot time=0x200
                                 * max collision retry = 0xf */
#define CONF_PROMISC  0x2e
        0x0000,                 /* no HDLC : normal CRC : enable broadcast
                                 * disable promiscuous/multicast modes */
        0x003c,                 /* minimum frame length = 60 octets) */

        0x0000,Cmd_SetAddr,
        0x003e,                 /* link to next command */
#define CONF_HWADDR  0x38
        0x0000,0x0000,0x0000,   /* hardware address placed here */

        0x0000,Cmd_MCast,
        0x0076,                 /* link to next command */
#define CONF_NR_MULTICAST 0x44
        0x0000,                 /* number of bytes in multicast address(es) */
#define CONF_MULTICAST 0x46
        0x0000, 0x0000, 0x0000, /* some addresses */
        0x0000, 0x0000, 0x0000,
        0x0000, 0x0000, 0x0000,
        0x0000, 0x0000, 0x0000,
        0x0000, 0x0000, 0x0000,
        0x0000, 0x0000, 0x0000,
        0x0000, 0x0000, 0x0000,
        0x0000, 0x0000, 0x0000,

#define CONF_DIAG_RESULT  0x76
        0x0000, Cmd_Diag,
        0x007c,                 /* link to next command */

        0x0000,Cmd_TDR|Cmd_INT,
        0x0084,
#define CONF_TDR_RESULT  0x82
        0x0000,

        0x0000,Cmd_END|Cmd_Nop, /* end of configure sequence */
        0x0084                  /* dummy link */
};

/* maps irq number to EtherExpress magic value */
static char irqrmap[] = { 0,0,1,2,3,4,0,0,0,1,5,6,0,0,0,0 };

#ifdef CONFIG_MCA_LEGACY
/* mapping of the first four bits of the second POS register */
static unsigned short mca_iomap[] = {
        0x270, 0x260, 0x250, 0x240, 0x230, 0x220, 0x210, 0x200,
        0x370, 0x360, 0x350, 0x340, 0x330, 0x320, 0x310, 0x300
};
/* bits 5-7 of the second POS register */
static char mca_irqmap[] = { 12, 9, 3, 4, 5, 10, 11, 15 };
#endif

/*
 * Prototypes for Linux interface
 */

static int eexp_open(struct net_device *dev);
static int eexp_close(struct net_device *dev);
static void eexp_timeout(struct net_device *dev);
static netdev_tx_t eexp_xmit(struct sk_buff *buf,
                             struct net_device *dev);

static irqreturn_t eexp_irq(int irq, void *dev_addr);
static void eexp_set_multicast(struct net_device *dev);

/*
 * Prototypes for hardware access functions
 */

static void eexp_hw_rx_pio(struct net_device *dev);
static void eexp_hw_tx_pio(struct net_device *dev, unsigned short *buf,
                       unsigned short len);
static int eexp_hw_probe(struct net_device *dev,unsigned short ioaddr);
static unsigned short eexp_hw_readeeprom(unsigned short ioaddr,
                                         unsigned char location);

static unsigned short eexp_hw_lasttxstat(struct net_device *dev);
static void eexp_hw_txrestart(struct net_device *dev);

static void eexp_hw_txinit    (struct net_device *dev);
static void eexp_hw_rxinit    (struct net_device *dev);

static void eexp_hw_init586   (struct net_device *dev);
static void eexp_setup_filter (struct net_device *dev);

static char *eexp_ifmap[]={"AUI", "BNC", "RJ45"};
enum eexp_iftype {AUI=0, BNC=1, TPE=2};

#define STARTED_RU      2
#define STARTED_CU      1

/*
 * Primitive hardware access functions.
 */

static inline unsigned short scb_status(struct net_device *dev)
{
        return inw(dev->base_addr + 0xc008);
}

static inline unsigned short scb_rdcmd(struct net_device *dev)
{
        return inw(dev->base_addr + 0xc00a);
}

static inline void scb_command(struct net_device *dev, unsigned short cmd)
{
        outw(cmd, dev->base_addr + 0xc00a);
}

static inline void scb_wrcbl(struct net_device *dev, unsigned short val)
{
        outw(val, dev->base_addr + 0xc00c);
}

static inline void scb_wrrfa(struct net_device *dev, unsigned short val)
{
        outw(val, dev->base_addr + 0xc00e);
}

static inline void set_loopback(struct net_device *dev)
{
        outb(inb(dev->base_addr + Config) | 2, dev->base_addr + Config);
}

static inline void clear_loopback(struct net_device *dev)
{
        outb(inb(dev->base_addr + Config) & ~2, dev->base_addr + Config);
}

static inline unsigned short int SHADOW(short int addr)
{
        addr &= 0x1f;
        if (addr > 0xf) addr += 0x3ff0;
        return addr + 0x4000;
}

/*
 * Linux interface
 */

/*
 * checks for presence of EtherExpress card
 */

static int __init do_express_probe(struct net_device *dev)
{
        unsigned short *port;
        static unsigned short ports[] = { 0x240,0x300,0x310,0x270,0x320,0x340,0 };
        unsigned short ioaddr = dev->base_addr;
        int dev_irq = dev->irq;
        int err;

        dev->if_port = 0xff; /* not set */

#ifdef CONFIG_MCA_LEGACY
        if (MCA_bus) {
                int slot = 0;

                /*
                 * Only find one card at a time.  Subsequent calls
                 * will find others, however, proper multicard MCA
                 * probing and setup can't be done with the
                 * old-style Space.c init routines.  -- ASF
                 */
                while (slot != MCA_NOTFOUND) {
                        int pos0, pos1;

                        slot = mca_find_unused_adapter(0x628B, slot);
                        if (slot == MCA_NOTFOUND)
                                break;

                        pos0 = mca_read_stored_pos(slot, 2);
                        pos1 = mca_read_stored_pos(slot, 3);
                        ioaddr = mca_iomap[pos1&0xf];

                        dev->irq = mca_irqmap[(pos1>>4)&0x7];

                        /*
                         * XXX: Transciever selection is done
                         * differently on the MCA version.
                         * How to get it to select something
                         * other than external/AUI is currently
                         * unknown.  This code is just for looks. -- ASF
                         */
                        if ((pos0 & 0x7) == 0x1)
                                dev->if_port = AUI;
                        else if ((pos0 & 0x7) == 0x5) {
                                if (pos1 & 0x80)
                                        dev->if_port = BNC;
                                else
                                        dev->if_port = TPE;
                        }

                        mca_set_adapter_name(slot, "Intel EtherExpress 16 MCA");
                        mca_set_adapter_procfn(slot, NULL, dev);
                        mca_mark_as_used(slot);

                        break;
                }
        }
#endif
        if (ioaddr&0xfe00) {
                if (!request_region(ioaddr, EEXP_IO_EXTENT, "EtherExpress"))
                        return -EBUSY;
                err = eexp_hw_probe(dev,ioaddr);
                release_region(ioaddr, EEXP_IO_EXTENT);
                return err;
        } else if (ioaddr)
                return -ENXIO;

        for (port=&ports[0] ; *port ; port++ )
        {
                unsigned short sum = 0;
                int i;
                if (!request_region(*port, EEXP_IO_EXTENT, "EtherExpress"))
                        continue;
                for ( i=0 ; i<4 ; i++ )
                {
                        unsigned short t;
                        t = inb(*port + ID_PORT);
                        sum |= (t>>4) << ((t & 0x03)<<2);
                }
                if (sum==0xbaba && !eexp_hw_probe(dev,*port)) {
                        release_region(*port, EEXP_IO_EXTENT);
                        return 0;
                }
                release_region(*port, EEXP_IO_EXTENT);
                dev->irq = dev_irq;
        }
        return -ENODEV;
}

#ifndef MODULE
struct net_device * __init express_probe(int unit)
{
        struct net_device *dev = alloc_etherdev(sizeof(struct net_local));
        int err;

        if (!dev)
                return ERR_PTR(-ENOMEM);

        sprintf(dev->name, "eth%d", unit);
        netdev_boot_setup_check(dev);

        err = do_express_probe(dev);
        if (!err)
                return dev;
        free_netdev(dev);
        return ERR_PTR(err);
}
#endif

/*
 * open and initialize the adapter, ready for use
 */

static int eexp_open(struct net_device *dev)
{
        int ret;
        unsigned short ioaddr = dev->base_addr;
        struct net_local *lp = netdev_priv(dev);

#if NET_DEBUG > 6
        printk(KERN_DEBUG "%s: eexp_open()\n", dev->name);
#endif

        if (!dev->irq || !irqrmap[dev->irq])
                return -ENXIO;

        ret = request_irq(dev->irq, &eexp_irq, 0, dev->name, dev);
        if (ret)
                return ret;

        if (!request_region(ioaddr, EEXP_IO_EXTENT, "EtherExpress")) {
                printk(KERN_WARNING "EtherExpress io port %x, is busy.\n"
                        , ioaddr);
                goto err_out1;
        }
        if (!request_region(ioaddr+0x4000, EEXP_IO_EXTENT, "EtherExpress shadow")) {
                printk(KERN_WARNING "EtherExpress io port %x, is busy.\n"
                        , ioaddr+0x4000);
                goto err_out2;
        }
        if (!request_region(ioaddr+0x8000, EEXP_IO_EXTENT, "EtherExpress shadow")) {
                printk(KERN_WARNING "EtherExpress io port %x, is busy.\n"
                        , ioaddr+0x8000);
                goto err_out3;
        }
        if (!request_region(ioaddr+0xc000, EEXP_IO_EXTENT, "EtherExpress shadow")) {
                printk(KERN_WARNING "EtherExpress io port %x, is busy.\n"
                        , ioaddr+0xc000);
                goto err_out4;
        }

        if (lp->width) {
                printk("%s: forcing ASIC to 8-bit mode\n", dev->name);
                outb(inb(dev->base_addr+Config)&~4, dev->base_addr+Config);
        }

        eexp_hw_init586(dev);
        netif_start_queue(dev);
#if NET_DEBUG > 6
        printk(KERN_DEBUG "%s: leaving eexp_open()\n", dev->name);
#endif
        return 0;

        err_out4:
                release_region(ioaddr+0x8000, EEXP_IO_EXTENT);
        err_out3:
                release_region(ioaddr+0x4000, EEXP_IO_EXTENT);
        err_out2:
                release_region(ioaddr, EEXP_IO_EXTENT);
        err_out1:
                free_irq(dev->irq, dev);
                return -EBUSY;
}

/*
 * close and disable the interface, leaving the 586 in reset.
 */

static int eexp_close(struct net_device *dev)
{
        unsigned short ioaddr = dev->base_addr;
        struct net_local *lp = netdev_priv(dev);

        int irq = dev->irq;

        netif_stop_queue(dev);

        outb(SIRQ_dis|irqrmap[irq],ioaddr+SET_IRQ);
        lp->started = 0;
        scb_command(dev, SCB_CUsuspend|SCB_RUsuspend);
        outb(0,ioaddr+SIGNAL_CA);
        free_irq(irq,dev);
        outb(i586_RST,ioaddr+EEPROM_Ctrl);
        release_region(ioaddr, EEXP_IO_EXTENT);
        release_region(ioaddr+0x4000, 16);
        release_region(ioaddr+0x8000, 16);
        release_region(ioaddr+0xc000, 16);

        return 0;
}

/*
 * This gets called when a higher level thinks we are broken.  Check that
 * nothing has become jammed in the CU.
 */

static void unstick_cu(struct net_device *dev)
{
        struct net_local *lp = netdev_priv(dev);
        unsigned short ioaddr = dev->base_addr;

        if (lp->started)
        {
                if (time_after(jiffies, dev->trans_start + 50))
                {
                        if (lp->tx_link==lp->last_tx_restart)
                        {
                                unsigned short boguscount=200,rsst;
                                printk(KERN_WARNING "%s: Retransmit timed out, status %04x, resetting...\n",
                                       dev->name, scb_status(dev));
                                eexp_hw_txinit(dev);
                                lp->last_tx_restart = 0;
                                scb_wrcbl(dev, lp->tx_link);
                                scb_command(dev, SCB_CUstart);
                                outb(0,ioaddr+SIGNAL_CA);
                                while (!SCB_complete(rsst=scb_status(dev)))
                                {
                                        if (!--boguscount)
                                        {
                                                boguscount=200;
                                                printk(KERN_WARNING "%s: Reset timed out status %04x, retrying...\n",
                                                       dev->name,rsst);
                                                scb_wrcbl(dev, lp->tx_link);
                                                scb_command(dev, SCB_CUstart);
                                                outb(0,ioaddr+SIGNAL_CA);
                                        }
                                }
                                netif_wake_queue(dev);
                        }
                        else
                        {
                                unsigned short status = scb_status(dev);
                                if (SCB_CUdead(status))
                                {
                                        unsigned short txstatus = eexp_hw_lasttxstat(dev);
                                        printk(KERN_WARNING "%s: Transmit timed out, CU not active status %04x %04x, restarting...\n",
                                               dev->name, status, txstatus);
                                        eexp_hw_txrestart(dev);
                                }
                                else
                                {
                                        unsigned short txstatus = eexp_hw_lasttxstat(dev);
                                        if (netif_queue_stopped(dev) && !txstatus)
                                        {
                                                printk(KERN_WARNING "%s: CU wedged, status %04x %04x, resetting...\n",
                                                       dev->name,status,txstatus);
                                                eexp_hw_init586(dev);
                                                netif_wake_queue(dev);
                                        }
                                        else
                                        {
                                                printk(KERN_WARNING "%s: transmit timed out\n", dev->name);
                                        }
                                }
                        }
                }
        }
        else
        {
                if (time_after(jiffies, lp->init_time + 10))
                {
                        unsigned short status = scb_status(dev);
                        printk(KERN_WARNING "%s: i82586 startup timed out, status %04x, resetting...\n",
                               dev->name, status);
                        eexp_hw_init586(dev);
                        netif_wake_queue(dev);
                }
        }
}

static void eexp_timeout(struct net_device *dev)
{
        struct net_local *lp = netdev_priv(dev);
#ifdef CONFIG_SMP
        unsigned long flags;
#endif
        int status;

        disable_irq(dev->irq);

        /*
         *      Best would be to use synchronize_irq(); spin_lock() here
         *      lets make it work first..
         */

#ifdef CONFIG_SMP
        spin_lock_irqsave(&lp->lock, flags);
#endif

        status = scb_status(dev);
        unstick_cu(dev);
        printk(KERN_INFO "%s: transmit timed out, %s?\n", dev->name,
               (SCB_complete(status)?"lost interrupt":
                "board on fire"));
        dev->stats.tx_errors++;
        lp->last_tx = jiffies;
        if (!SCB_complete(status)) {
                scb_command(dev, SCB_CUabort);
                outb(0,dev->base_addr+SIGNAL_CA);
        }
        netif_wake_queue(dev);
#ifdef CONFIG_SMP
        spin_unlock_irqrestore(&lp->lock, flags);
#endif
}

/*
 * Called to transmit a packet, or to allow us to right ourselves
 * if the kernel thinks we've died.
 */
static netdev_tx_t eexp_xmit(struct sk_buff *buf, struct net_device *dev)
{
        short length = buf->len;
#ifdef CONFIG_SMP
        struct net_local *lp = netdev_priv(dev);
        unsigned long flags;
#endif

#if NET_DEBUG > 6
        printk(KERN_DEBUG "%s: eexp_xmit()\n", dev->name);
#endif

        if (buf->len < ETH_ZLEN) {
                if (skb_padto(buf, ETH_ZLEN))
                        return NETDEV_TX_OK;
                length = ETH_ZLEN;
        }

        disable_irq(dev->irq);

        /*
         *      Best would be to use synchronize_irq(); spin_lock() here
         *      lets make it work first..
         */

#ifdef CONFIG_SMP
        spin_lock_irqsave(&lp->lock, flags);
#endif

        {
                unsigned short *data = (unsigned short *)buf->data;

                dev->stats.tx_bytes += length;

                eexp_hw_tx_pio(dev,data,length);
        }
        dev_kfree_skb(buf);
#ifdef CONFIG_SMP
        spin_unlock_irqrestore(&lp->lock, flags);
#endif
        enable_irq(dev->irq);
        return NETDEV_TX_OK;
}

/*
 * Handle an EtherExpress interrupt
 * If we've finished initializing, start the RU and CU up.
 * If we've already started, reap tx buffers, handle any received packets,
 * check to make sure we've not become wedged.
 */

static unsigned short eexp_start_irq(struct net_device *dev,
                                     unsigned short status)
{
        unsigned short ack_cmd = SCB_ack(status);
        struct net_local *lp = netdev_priv(dev);
        unsigned short ioaddr = dev->base_addr;
        if ((dev->flags & IFF_UP) && !(lp->started & STARTED_CU)) {
                short diag_status, tdr_status;
                while (SCB_CUstat(status)==2)
                        status = scb_status(dev);
#if NET_DEBUG > 4
                printk("%s: CU went non-active (status %04x)\n",
                       dev->name, status);
#endif

                outw(CONF_DIAG_RESULT & ~31, ioaddr + SM_PTR);
                diag_status = inw(ioaddr + SHADOW(CONF_DIAG_RESULT));
                if (diag_status & 1<<11) {
                        printk(KERN_WARNING "%s: 82586 failed self-test\n",
                               dev->name);
                } else if (!(diag_status & 1<<13)) {
                        printk(KERN_WARNING "%s: 82586 self-test failed to complete\n", dev->name);
                }

                outw(CONF_TDR_RESULT & ~31, ioaddr + SM_PTR);
                tdr_status = inw(ioaddr + SHADOW(CONF_TDR_RESULT));
                if (tdr_status & (TDR_SHORT|TDR_OPEN)) {
                        printk(KERN_WARNING "%s: TDR reports cable %s at %d tick%s\n", dev->name, (tdr_status & TDR_SHORT)?"short":"broken", tdr_status & TDR_TIME, ((tdr_status & TDR_TIME) != 1) ? "s" : "");
                }
                else if (tdr_status & TDR_XCVRPROBLEM) {
                        printk(KERN_WARNING "%s: TDR reports transceiver problem\n", dev->name);
                }
                else if (tdr_status & TDR_LINKOK) {
#if NET_DEBUG > 4
                        printk(KERN_DEBUG "%s: TDR reports link OK\n", dev->name);
#endif
                } else {
                        printk("%s: TDR is ga-ga (status %04x)\n", dev->name,
                               tdr_status);
                }

                lp->started |= STARTED_CU;
                scb_wrcbl(dev, lp->tx_link);
                /* if the RU isn't running, start it now */
                if (!(lp->started & STARTED_RU)) {
                        ack_cmd |= SCB_RUstart;
                        scb_wrrfa(dev, lp->rx_buf_start);
                        lp->rx_ptr = lp->rx_buf_start;
                        lp->started |= STARTED_RU;
                }
                ack_cmd |= SCB_CUstart | 0x2000;
        }

        if ((dev->flags & IFF_UP) && !(lp->started & STARTED_RU) && SCB_RUstat(status)==4)
                lp->started|=STARTED_RU;

        return ack_cmd;
}

static void eexp_cmd_clear(struct net_device *dev)
{
        unsigned long int oldtime = jiffies;
        while (scb_rdcmd(dev) && (time_before(jiffies, oldtime + 10)));
        if (scb_rdcmd(dev)) {
                printk("%s: command didn't clear\n", dev->name);
        }
}

static irqreturn_t eexp_irq(int dummy, void *dev_info)
{
        struct net_device *dev = dev_info;
        struct net_local *lp;
        unsigned short ioaddr,status,ack_cmd;
        unsigned short old_read_ptr, old_write_ptr;

        lp = netdev_priv(dev);
        ioaddr = dev->base_addr;

        spin_lock(&lp->lock);

        old_read_ptr = inw(ioaddr+READ_PTR);
        old_write_ptr = inw(ioaddr+WRITE_PTR);

        outb(SIRQ_dis|irqrmap[dev->irq], ioaddr+SET_IRQ);

        status = scb_status(dev);

#if NET_DEBUG > 4
        printk(KERN_DEBUG "%s: interrupt (status %x)\n", dev->name, status);
#endif

        if (lp->started == (STARTED_CU | STARTED_RU)) {

                do {
                        eexp_cmd_clear(dev);

                        ack_cmd = SCB_ack(status);
                        scb_command(dev, ack_cmd);
                        outb(0,ioaddr+SIGNAL_CA);

                        eexp_cmd_clear(dev);

                        if (SCB_complete(status)) {
                                if (!eexp_hw_lasttxstat(dev)) {
                                        printk("%s: tx interrupt but no status\n", dev->name);
                                }
                        }

                        if (SCB_rxdframe(status))
                                eexp_hw_rx_pio(dev);

                        status = scb_status(dev);
                } while (status & 0xc000);

                if (SCB_RUdead(status))
                {
                        printk(KERN_WARNING "%s: RU stopped: status %04x\n",
                               dev->name,status);
#if 0
                        printk(KERN_WARNING "%s: cur_rfd=%04x, cur_rbd=%04x\n", dev->name, lp->cur_rfd, lp->cur_rbd);
                        outw(lp->cur_rfd, ioaddr+READ_PTR);
                        printk(KERN_WARNING "%s: [%04x]\n", dev->name, inw(ioaddr+DATAPORT));
                        outw(lp->cur_rfd+6, ioaddr+READ_PTR);
                        printk(KERN_WARNING "%s: rbd is %04x\n", dev->name, rbd= inw(ioaddr+DATAPORT));
                        outw(rbd, ioaddr+READ_PTR);
                        printk(KERN_WARNING "%s: [%04x %04x] ", dev->name, inw(ioaddr+DATAPORT), inw(ioaddr+DATAPORT));
                        outw(rbd+8, ioaddr+READ_PTR);
                        printk("[%04x]\n", inw(ioaddr+DATAPORT));
#endif
                        dev->stats.rx_errors++;
#if 1
                        eexp_hw_rxinit(dev);
#else
                        lp->cur_rfd = lp->first_rfd;
#endif
                        scb_wrrfa(dev, lp->rx_buf_start);
                        scb_command(dev, SCB_RUstart);
                        outb(0,ioaddr+SIGNAL_CA);
                }
        } else {
                if (status & 0x8000)
                        ack_cmd = eexp_start_irq(dev, status);
                else
                        ack_cmd = SCB_ack(status);
                scb_command(dev, ack_cmd);
                outb(0,ioaddr+SIGNAL_CA);
        }

        eexp_cmd_clear(dev);

        outb(SIRQ_en|irqrmap[dev->irq], ioaddr+SET_IRQ);

#if NET_DEBUG > 6
        printk("%s: leaving eexp_irq()\n", dev->name);
#endif
        outw(old_read_ptr, ioaddr+READ_PTR);
        outw(old_write_ptr, ioaddr+WRITE_PTR);

        spin_unlock(&lp->lock);
        return IRQ_HANDLED;
}

/*
 * Hardware access functions
 */

/*
 * Set the cable type to use.
 */

static void eexp_hw_set_interface(struct net_device *dev)
{
        unsigned char oldval = inb(dev->base_addr + 0x300e);
        oldval &= ~0x82;
        switch (dev->if_port) {
        case TPE:
                oldval |= 0x2;
        case BNC:
                oldval |= 0x80;
                break;
        }
        outb(oldval, dev->base_addr+0x300e);
        mdelay(20);
}

/*
 * Check all the receive buffers, and hand any received packets
 * to the upper levels. Basic sanity check on each frame
 * descriptor, though we don't bother trying to fix broken ones.
 */

static void eexp_hw_rx_pio(struct net_device *dev)
{
        struct net_local *lp = netdev_priv(dev);
        unsigned short rx_block = lp->rx_ptr;
        unsigned short boguscount = lp->num_rx_bufs;
        unsigned short ioaddr = dev->base_addr;
        unsigned short status;

#if NET_DEBUG > 6
        printk(KERN_DEBUG "%s: eexp_hw_rx()\n", dev->name);
#endif

        do {
                unsigned short rfd_cmd, rx_next, pbuf, pkt_len;

                outw(rx_block, ioaddr + READ_PTR);
                status = inw(ioaddr + DATAPORT);

                if (FD_Done(status))
                {
                        rfd_cmd = inw(ioaddr + DATAPORT);
                        rx_next = inw(ioaddr + DATAPORT);
                        pbuf = inw(ioaddr + DATAPORT);

                        outw(pbuf, ioaddr + READ_PTR);
                        pkt_len = inw(ioaddr + DATAPORT);

                        if (rfd_cmd!=0x0000)
                        {
                                printk(KERN_WARNING "%s: rfd_cmd not zero:0x%04x\n",
                                       dev->name, rfd_cmd);
                                continue;
                        }
                        else if (pbuf!=rx_block+0x16)
                        {
                                printk(KERN_WARNING "%s: rfd and rbd out of sync 0x%04x 0x%04x\n",
                                       dev->name, rx_block+0x16, pbuf);
                                continue;
                        }
                        else if ((pkt_len & 0xc000)!=0xc000)
                        {
                                printk(KERN_WARNING "%s: EOF or F not set on received buffer (%04x)\n",
                                       dev->name, pkt_len & 0xc000);
                                continue;
                        }
                        else if (!FD_OK(status))
                        {
                                dev->stats.rx_errors++;
                                if (FD_CRC(status))
                                        dev->stats.rx_crc_errors++;
                                if (FD_Align(status))
                                        dev->stats.rx_frame_errors++;
                                if (FD_Resrc(status))
                                        dev->stats.rx_fifo_errors++;
                                if (FD_DMA(status))
                                        dev->stats.rx_over_errors++;
                                if (FD_Short(status))
                                        dev->stats.rx_length_errors++;
                        }
                        else
                        {
                                struct sk_buff *skb;
                                pkt_len &= 0x3fff;
                                skb = dev_alloc_skb(pkt_len+16);
                                if (skb == NULL)
                                {
                                        printk(KERN_WARNING "%s: Memory squeeze, dropping packet\n",dev->name);
                                        dev->stats.rx_dropped++;
                                        break;
                                }
                                skb_reserve(skb, 2);
                                outw(pbuf+10, ioaddr+READ_PTR);
                                insw(ioaddr+DATAPORT, skb_put(skb,pkt_len),(pkt_len+1)>>1);
                                skb->protocol = eth_type_trans(skb,dev);
                                netif_rx(skb);
                                dev->stats.rx_packets++;
                                dev->stats.rx_bytes += pkt_len;
                        }
                        outw(rx_block, ioaddr+WRITE_PTR);
                        outw(0, ioaddr+DATAPORT);
                        outw(0, ioaddr+DATAPORT);
                        rx_block = rx_next;
                }
        } while (FD_Done(status) && boguscount--);
        lp->rx_ptr = rx_block;
}

/*
 * Hand a packet to the card for transmission
 * If we get here, we MUST have already checked
 * to make sure there is room in the transmit
 * buffer region.
 */

static void eexp_hw_tx_pio(struct net_device *dev, unsigned short *buf,
                       unsigned short len)
{
        struct net_local *lp = netdev_priv(dev);
        unsigned short ioaddr = dev->base_addr;

        if (LOCKUP16 || lp->width) {
                /* Stop the CU so that there is no chance that it
                   jumps off to a bogus address while we are writing the
                   pointer to the next transmit packet in 8-bit mode --
                   this eliminates the "CU wedged" errors in 8-bit mode.

                   (Zoltan Szilagyi 10-12-96) */
                scb_command(dev, SCB_CUsuspend);
                outw(0xFFFF, ioaddr+SIGNAL_CA);
        }

        outw(lp->tx_head, ioaddr + WRITE_PTR);

        outw(0x0000, ioaddr + DATAPORT);
        outw(Cmd_INT|Cmd_Xmit, ioaddr + DATAPORT);
        outw(lp->tx_head+0x08, ioaddr + DATAPORT);
        outw(lp->tx_head+0x0e, ioaddr + DATAPORT);

        outw(0x0000, ioaddr + DATAPORT);
        outw(0x0000, ioaddr + DATAPORT);
        outw(lp->tx_head+0x08, ioaddr + DATAPORT);

        outw(0x8000|len, ioaddr + DATAPORT);
        outw(-1, ioaddr + DATAPORT);
        outw(lp->tx_head+0x16, ioaddr + DATAPORT);
        outw(0, ioaddr + DATAPORT);

        outsw(ioaddr + DATAPORT, buf, (len+1)>>1);

        outw(lp->tx_tail+0xc, ioaddr + WRITE_PTR);
        outw(lp->tx_head, ioaddr + DATAPORT);

        dev->trans_start = jiffies;
        lp->tx_tail = lp->tx_head;
        if (lp->tx_head==TX_BUF_START+((lp->num_tx_bufs-1)*TX_BUF_SIZE))
                lp->tx_head = TX_BUF_START;
        else
                lp->tx_head += TX_BUF_SIZE;
        if (lp->tx_head != lp->tx_reap)
                netif_wake_queue(dev);

        if (LOCKUP16 || lp->width) {
                /* Restart the CU so that the packet can actually
                   be transmitted. (Zoltan Szilagyi 10-12-96) */
                scb_command(dev, SCB_CUresume);
                outw(0xFFFF, ioaddr+SIGNAL_CA);
        }

        dev->stats.tx_packets++;
        lp->last_tx = jiffies;
}

static const struct net_device_ops eexp_netdev_ops = {
        .ndo_open               = eexp_open,
        .ndo_stop               = eexp_close,
        .ndo_start_xmit         = eexp_xmit,
        .ndo_set_multicast_list = eexp_set_multicast,
        .ndo_tx_timeout         = eexp_timeout,
        .ndo_change_mtu         = eth_change_mtu,
        .ndo_set_mac_address    = eth_mac_addr,
        .ndo_validate_addr      = eth_validate_addr,
};

/*
 * Sanity check the suspected EtherExpress card
 * Read hardware address, reset card, size memory and initialize buffer
 * memory pointers. These are held in netdev_priv(), in case someone has more
 * than one card in a machine.
 */

static int __init eexp_hw_probe(struct net_device *dev, unsigned short ioaddr)
{
        unsigned short hw_addr[3];
        unsigned char buswidth;
        unsigned int memory_size;
        int i;
        unsigned short xsum = 0;
        struct net_local *lp = netdev_priv(dev);

        printk("%s: EtherExpress 16 at %#x ",dev->name,ioaddr);

        outb(ASIC_RST, ioaddr+EEPROM_Ctrl);
        outb(0, ioaddr+EEPROM_Ctrl);
        udelay(500);
        outb(i586_RST, ioaddr+EEPROM_Ctrl);

        hw_addr[0] = eexp_hw_readeeprom(ioaddr,2);
        hw_addr[1] = eexp_hw_readeeprom(ioaddr,3);
        hw_addr[2] = eexp_hw_readeeprom(ioaddr,4);

        /* Standard Address or Compaq LTE Address */
        if (!((hw_addr[2]==0x00aa && ((hw_addr[1] & 0xff00)==0x0000)) ||
              (hw_addr[2]==0x0080 && ((hw_addr[1] & 0xff00)==0x5F00))))
        {
                printk(" rejected: invalid address %04x%04x%04x\n",
                        hw_addr[2],hw_addr[1],hw_addr[0]);
                return -ENODEV;
        }

        /* Calculate the EEPROM checksum.  Carry on anyway if it's bad,
         * though.
         */
        for (i = 0; i < 64; i++)
                xsum += eexp_hw_readeeprom(ioaddr, i);
        if (xsum != 0xbaba)
                printk(" (bad EEPROM xsum 0x%02x)", xsum);

        dev->base_addr = ioaddr;
        for ( i=0 ; i<6 ; i++ )
                dev->dev_addr[i] = ((unsigned char *)hw_addr)[5-i];

        {
                static char irqmap[]={0, 9, 3, 4, 5, 10, 11, 0};
                unsigned short setupval = eexp_hw_readeeprom(ioaddr,0);

                /* Use the IRQ from EEPROM if none was given */
                if (!dev->irq)
                        dev->irq = irqmap[setupval>>13];

                if (dev->if_port == 0xff) {
                        dev->if_port = !(setupval & 0x1000) ? AUI :
                                eexp_hw_readeeprom(ioaddr,5) & 0x1 ? TPE : BNC;
                }

                buswidth = !((setupval & 0x400) >> 10);
        }

        memset(lp, 0, sizeof(struct net_local));
        spin_lock_init(&lp->lock);

        printk("(IRQ %d, %s connector, %d-bit bus", dev->irq,
               eexp_ifmap[dev->if_port], buswidth?8:16);

        if (!request_region(dev->base_addr + 0x300e, 1, "EtherExpress"))
                return -EBUSY;

        eexp_hw_set_interface(dev);

        release_region(dev->base_addr + 0x300e, 1);

        /* Find out how much RAM we have on the card */
        outw(0, dev->base_addr + WRITE_PTR);
        for (i = 0; i < 32768; i++)
                outw(0, dev->base_addr + DATAPORT);

        for (memory_size = 0; memory_size < 64; memory_size++)
        {
                outw(memory_size<<10, dev->base_addr + READ_PTR);
                if (inw(dev->base_addr+DATAPORT))
                        break;
                outw(memory_size<<10, dev->base_addr + WRITE_PTR);
                outw(memory_size | 0x5000, dev->base_addr+DATAPORT);
                outw(memory_size<<10, dev->base_addr + READ_PTR);
                if (inw(dev->base_addr+DATAPORT) != (memory_size | 0x5000))
                        break;
        }

        /* Sort out the number of buffers.  We may have 16, 32, 48 or 64k
         * of RAM to play with.
         */
        lp->num_tx_bufs = 4;
        lp->rx_buf_end = 0x3ff6;
        switch (memory_size)
        {
        case 64:
                lp->rx_buf_end += 0x4000;
        case 48:
                lp->num_tx_bufs += 4;
                lp->rx_buf_end += 0x4000;
        case 32:
                lp->rx_buf_end += 0x4000;
        case 16:
                printk(", %dk RAM)\n", memory_size);
                break;
        default:
                printk(") bad memory size (%dk).\n", memory_size);
                return -ENODEV;
                break;
        }

        lp->rx_buf_start = TX_BUF_START + (lp->num_tx_bufs*TX_BUF_SIZE);
        lp->width = buswidth;

        dev->netdev_ops = &eexp_netdev_ops;
        dev->watchdog_timeo = 2*HZ;

        return register_netdev(dev);
}

/*
 * Read a word from the EtherExpress on-board serial EEPROM.
 * The EEPROM contains 64 words of 16 bits.
 */
static unsigned short __init eexp_hw_readeeprom(unsigned short ioaddr,
                                                    unsigned char location)
{
        unsigned short cmd = 0x180|(location&0x7f);
        unsigned short rval = 0,wval = EC_CS|i586_RST;
        int i;

        outb(EC_CS|i586_RST,ioaddr+EEPROM_Ctrl);
        for (i=0x100 ; i ; i>>=1 )
        {
                if (cmd&i)
                        wval |= EC_Wr;
                else
                        wval &= ~EC_Wr;

                outb(wval,ioaddr+EEPROM_Ctrl);
                outb(wval|EC_Clk,ioaddr+EEPROM_Ctrl);
                eeprom_delay();
                outb(wval,ioaddr+EEPROM_Ctrl);
                eeprom_delay();
        }
        wval &= ~EC_Wr;
        outb(wval,ioaddr+EEPROM_Ctrl);
        for (i=0x8000 ; i ; i>>=1 )
        {
                outb(wval|EC_Clk,ioaddr+EEPROM_Ctrl);
                eeprom_delay();
                if (inb(ioaddr+EEPROM_Ctrl)&EC_Rd)
                        rval |= i;
                outb(wval,ioaddr+EEPROM_Ctrl);
                eeprom_delay();
        }
        wval &= ~EC_CS;
        outb(wval|EC_Clk,ioaddr+EEPROM_Ctrl);
        eeprom_delay();
        outb(wval,ioaddr+EEPROM_Ctrl);
        eeprom_delay();
        return rval;
}

/*
 * Reap tx buffers and return last transmit status.
 * if ==0 then either:
 *    a) we're not transmitting anything, so why are we here?
 *    b) we've died.
 * otherwise, Stat_Busy(return) means we've still got some packets
 * to transmit, Stat_Done(return) means our buffers should be empty
 * again
 */

static unsigned short eexp_hw_lasttxstat(struct net_device *dev)
{
        struct net_local *lp = netdev_priv(dev);
        unsigned short tx_block = lp->tx_reap;
        unsigned short status;

        if (!netif_queue_stopped(dev) && lp->tx_head==lp->tx_reap)
                return 0x0000;

        do
        {
                outw(tx_block & ~31, dev->base_addr + SM_PTR);
                status = inw(dev->base_addr + SHADOW(tx_block));
                if (!Stat_Done(status))
                {
                        lp->tx_link = tx_block;
                        return status;
                }
                else
                {
                        lp->last_tx_restart = 0;
                        dev->stats.collisions += Stat_NoColl(status);
                        if (!Stat_OK(status))
                        {
                                char *whatsup = NULL;
                                dev->stats.tx_errors++;
                                if (Stat_Abort(status))
                                        dev->stats.tx_aborted_errors++;
                                if (Stat_TNoCar(status)) {
                                        whatsup = "aborted, no carrier";
                                        dev->stats.tx_carrier_errors++;
                                }
                                if (Stat_TNoCTS(status)) {
                                        whatsup = "aborted, lost CTS";
                                        dev->stats.tx_carrier_errors++;
                                }
                                if (Stat_TNoDMA(status)) {
                                        whatsup = "FIFO underran";
                                        dev->stats.tx_fifo_errors++;
                                }
                                if (Stat_TXColl(status)) {
                                        whatsup = "aborted, too many collisions";
                                        dev->stats.tx_aborted_errors++;
                                }
                                if (whatsup)
                                        printk(KERN_INFO "%s: transmit %s\n",
                                               dev->name, whatsup);
                        }
                        else
                                dev->stats.tx_packets++;
                }
                if (tx_block == TX_BUF_START+((lp->num_tx_bufs-1)*TX_BUF_SIZE))
                        lp->tx_reap = tx_block = TX_BUF_START;
                else
                        lp->tx_reap = tx_block += TX_BUF_SIZE;
                netif_wake_queue(dev);
        }
        while (lp->tx_reap != lp->tx_head);

        lp->tx_link = lp->tx_tail + 0x08;

        return status;
}

/*
 * This should never happen. It is called when some higher routine detects
 * that the CU has stopped, to try to restart it from the last packet we knew
 * we were working on, or the idle loop if we had finished for the time.
 */

static void eexp_hw_txrestart(struct net_device *dev)
{
        struct net_local *lp = netdev_priv(dev);
        unsigned short ioaddr = dev->base_addr;

        lp->last_tx_restart = lp->tx_link;
        scb_wrcbl(dev, lp->tx_link);
        scb_command(dev, SCB_CUstart);
        outb(0,ioaddr+SIGNAL_CA);

        {
                unsigned short boguscount=50,failcount=5;
                while (!scb_status(dev))
                {
                        if (!--boguscount)
                        {
                                if (--failcount)
                                {
                                        printk(KERN_WARNING "%s: CU start timed out, status %04x, cmd %04x\n", dev->name, scb_status(dev), scb_rdcmd(dev));
                                        scb_wrcbl(dev, lp->tx_link);
                                        scb_command(dev, SCB_CUstart);
                                        outb(0,ioaddr+SIGNAL_CA);
                                        boguscount = 100;
                                }
                                else
                                {
                                        printk(KERN_WARNING "%s: Failed to restart CU, resetting board...\n",dev->name);
                                        eexp_hw_init586(dev);
                                        netif_wake_queue(dev);
                                        return;
                                }
                        }
                }
        }
}

/*
 * Writes down the list of transmit buffers into card memory.  Each
 * entry consists of an 82586 transmit command, followed by a jump
 * pointing to itself.  When we want to transmit a packet, we write
 * the data into the appropriate transmit buffer and then modify the
 * preceding jump to point at the new transmit command.  This means that
 * the 586 command unit is continuously active.
 */

static void eexp_hw_txinit(struct net_device *dev)
{
        struct net_local *lp = netdev_priv(dev);
        unsigned short tx_block = TX_BUF_START;
        unsigned short curtbuf;
        unsigned short ioaddr = dev->base_addr;

        for ( curtbuf=0 ; curtbuf<lp->num_tx_bufs ; curtbuf++ )
        {
                outw(tx_block, ioaddr + WRITE_PTR);

                outw(0x0000, ioaddr + DATAPORT);
                outw(Cmd_INT|Cmd_Xmit, ioaddr + DATAPORT);
                outw(tx_block+0x08, ioaddr + DATAPORT);
                outw(tx_block+0x0e, ioaddr + DATAPORT);

                outw(0x0000, ioaddr + DATAPORT);
                outw(0x0000, ioaddr + DATAPORT);
                outw(tx_block+0x08, ioaddr + DATAPORT);

                outw(0x8000, ioaddr + DATAPORT);
                outw(-1, ioaddr + DATAPORT);
                outw(tx_block+0x16, ioaddr + DATAPORT);
                outw(0x0000, ioaddr + DATAPORT);

                tx_block += TX_BUF_SIZE;
        }
        lp->tx_head = TX_BUF_START;
        lp->tx_reap = TX_BUF_START;
        lp->tx_tail = tx_block - TX_BUF_SIZE;
        lp->tx_link = lp->tx_tail + 0x08;
        lp->rx_buf_start = tx_block;

}

/*
 * Write the circular list of receive buffer descriptors to card memory.
 * The end of the list isn't marked, which means that the 82586 receive
 * unit will loop until buffers become available (this avoids it giving us
 * "out of resources" messages).
 */

static void eexp_hw_rxinit(struct net_device *dev)
{
        struct net_local *lp = netdev_priv(dev);
        unsigned short rx_block = lp->rx_buf_start;
        unsigned short ioaddr = dev->base_addr;

        lp->num_rx_bufs = 0;
        lp->rx_first = lp->rx_ptr = rx_block;
        do
        {
                lp->num_rx_bufs++;

                outw(rx_block, ioaddr + WRITE_PTR);

                outw(0, ioaddr + DATAPORT);  outw(0, ioaddr+DATAPORT);
                outw(rx_block + RX_BUF_SIZE, ioaddr+DATAPORT);
                outw(0xffff, ioaddr+DATAPORT);

                outw(0x0000, ioaddr+DATAPORT);
                outw(0xdead, ioaddr+DATAPORT);
                outw(0xdead, ioaddr+DATAPORT);
                outw(0xdead, ioaddr+DATAPORT);
                outw(0xdead, ioaddr+DATAPORT);
                outw(0xdead, ioaddr+DATAPORT);
                outw(0xdead, ioaddr+DATAPORT);

                outw(0x0000, ioaddr+DATAPORT);
                outw(rx_block + RX_BUF_SIZE + 0x16, ioaddr+DATAPORT);
                outw(rx_block + 0x20, ioaddr+DATAPORT);
                outw(0, ioaddr+DATAPORT);
                outw(RX_BUF_SIZE-0x20, ioaddr+DATAPORT);

                lp->rx_last = rx_block;
                rx_block += RX_BUF_SIZE;
        } while (rx_block <= lp->rx_buf_end-RX_BUF_SIZE);


        /* Make first Rx frame descriptor point to first Rx buffer
           descriptor */
        outw(lp->rx_first + 6, ioaddr+WRITE_PTR);
        outw(lp->rx_first + 0x16, ioaddr+DATAPORT);

        /* Close Rx frame descriptor ring */
        outw(lp->rx_last + 4, ioaddr+WRITE_PTR);
        outw(lp->rx_first, ioaddr+DATAPORT);

        /* Close Rx buffer descriptor ring */
        outw(lp->rx_last + 0x16 + 2, ioaddr+WRITE_PTR);
        outw(lp->rx_first + 0x16, ioaddr+DATAPORT);

}

/*
 * Un-reset the 586, and start the configuration sequence. We don't wait for
 * this to finish, but allow the interrupt handler to start the CU and RU for
 * us.  We can't start the receive/transmission system up before we know that
 * the hardware is configured correctly.
 */

static void eexp_hw_init586(struct net_device *dev)
{
        struct net_local *lp = netdev_priv(dev);
        unsigned short ioaddr = dev->base_addr;
        int i;

#if NET_DEBUG > 6
        printk("%s: eexp_hw_init586()\n", dev->name);
#endif

        lp->started = 0;

        set_loopback(dev);

        outb(SIRQ_dis|irqrmap[dev->irq],ioaddr+SET_IRQ);

        /* Download the startup code */
        outw(lp->rx_buf_end & ~31, ioaddr + SM_PTR);
        outw(lp->width?0x0001:0x0000, ioaddr + 0x8006);
        outw(0x0000, ioaddr + 0x8008);
        outw(0x0000, ioaddr + 0x800a);
        outw(0x0000, ioaddr + 0x800c);
        outw(0x0000, ioaddr + 0x800e);

        for (i = 0; i < ARRAY_SIZE(start_code) * 2; i+=32) {
                int j;
                outw(i, ioaddr + SM_PTR);
                for (j = 0; j < 16 && (i+j)/2 < ARRAY_SIZE(start_code); j+=2)
                        outw(start_code[(i+j)/2],
                             ioaddr+0x4000+j);
                for (j = 0; j < 16 && (i+j+16)/2 < ARRAY_SIZE(start_code); j+=2)
                        outw(start_code[(i+j+16)/2],
                             ioaddr+0x8000+j);
        }

        /* Do we want promiscuous mode or multicast? */
        outw(CONF_PROMISC & ~31, ioaddr+SM_PTR);
        i = inw(ioaddr+SHADOW(CONF_PROMISC));
        outw((dev->flags & IFF_PROMISC)?(i|1):(i & ~1),
             ioaddr+SHADOW(CONF_PROMISC));
        lp->was_promisc = dev->flags & IFF_PROMISC;
#if 0
        eexp_setup_filter(dev);
#endif

        /* Write our hardware address */
        outw(CONF_HWADDR & ~31, ioaddr+SM_PTR);
        outw(((unsigned short *)dev->dev_addr)[0], ioaddr+SHADOW(CONF_HWADDR));
        outw(((unsigned short *)dev->dev_addr)[1],
             ioaddr+SHADOW(CONF_HWADDR+2));
        outw(((unsigned short *)dev->dev_addr)[2],
             ioaddr+SHADOW(CONF_HWADDR+4));

        eexp_hw_txinit(dev);
        eexp_hw_rxinit(dev);

        outb(0,ioaddr+EEPROM_Ctrl);
        mdelay(5);

        scb_command(dev, 0xf000);
        outb(0,ioaddr+SIGNAL_CA);

        outw(0, ioaddr+SM_PTR);

        {
                unsigned short rboguscount=50,rfailcount=5;
                while (inw(ioaddr+0x4000))
                {
                        if (!--rboguscount)
                        {
                                printk(KERN_WARNING "%s: i82586 reset timed out, kicking...\n",
                                        dev->name);
                                scb_command(dev, 0);
                                outb(0,ioaddr+SIGNAL_CA);
                                rboguscount = 100;
                                if (!--rfailcount)
                                {
                                        printk(KERN_WARNING "%s: i82586 not responding, giving up.\n",
                                                dev->name);
                                        return;
                                }
                        }
                }
        }

        scb_wrcbl(dev, CONF_LINK);
        scb_command(dev, 0xf000|SCB_CUstart);
        outb(0,ioaddr+SIGNAL_CA);

        {
                unsigned short iboguscount=50,ifailcount=5;
                while (!scb_status(dev))
                {
                        if (!--iboguscount)
                        {
                                if (--ifailcount)
                                {
                                        printk(KERN_WARNING "%s: i82586 initialization timed out, status %04x, cmd %04x\n",
                                                dev->name, scb_status(dev), scb_rdcmd(dev));
                                        scb_wrcbl(dev, CONF_LINK);
                                        scb_command(dev, 0xf000|SCB_CUstart);
                                        outb(0,ioaddr+SIGNAL_CA);
                                        iboguscount = 100;
                                }
                                else
                                {
                                        printk(KERN_WARNING "%s: Failed to initialize i82586, giving up.\n",dev->name);
                                        return;
                                }
                        }
                }
        }

        clear_loopback(dev);
        outb(SIRQ_en|irqrmap[dev->irq],ioaddr+SET_IRQ);

        lp->init_time = jiffies;
#if NET_DEBUG > 6
        printk("%s: leaving eexp_hw_init586()\n", dev->name);
#endif
        return;
}

static void eexp_setup_filter(struct net_device *dev)
{
        struct dev_mc_list *dmi;
        unsigned short ioaddr = dev->base_addr;
        int count = dev->mc_count;
        int i;
        if (count > 8) {
                printk(KERN_INFO "%s: too many multicast addresses (%d)\n",
                       dev->name, count);
                count = 8;
        }

        outw(CONF_NR_MULTICAST & ~31, ioaddr+SM_PTR);
        outw(6*count, ioaddr+SHADOW(CONF_NR_MULTICAST));
        for (i = 0, dmi = dev->mc_list; i < count; i++, dmi = dmi->next) {
                unsigned short *data;
                if (!dmi) {
                        printk(KERN_INFO "%s: too few multicast addresses\n", dev->name);
                        break;
                }
                if (dmi->dmi_addrlen != ETH_ALEN) {
                        printk(KERN_INFO "%s: invalid multicast address length given.\n", dev->name);
                        continue;
                }
                data = (unsigned short *)dmi->dmi_addr;
                outw((CONF_MULTICAST+(6*i)) & ~31, ioaddr+SM_PTR);
                outw(data[0], ioaddr+SHADOW(CONF_MULTICAST+(6*i)));
                outw((CONF_MULTICAST+(6*i)+2) & ~31, ioaddr+SM_PTR);
                outw(data[1], ioaddr+SHADOW(CONF_MULTICAST+(6*i)+2));
                outw((CONF_MULTICAST+(6*i)+4) & ~31, ioaddr+SM_PTR);
                outw(data[2], ioaddr+SHADOW(CONF_MULTICAST+(6*i)+4));
        }
}

/*
 * Set or clear the multicast filter for this adaptor.
 */
static void
eexp_set_multicast(struct net_device *dev)
{
        unsigned short ioaddr = dev->base_addr;
        struct net_local *lp = netdev_priv(dev);
        int kick = 0, i;
        if ((dev->flags & IFF_PROMISC) != lp->was_promisc) {
                outw(CONF_PROMISC & ~31, ioaddr+SM_PTR);
                i = inw(ioaddr+SHADOW(CONF_PROMISC));
                outw((dev->flags & IFF_PROMISC)?(i|1):(i & ~1),
                     ioaddr+SHADOW(CONF_PROMISC));
                lp->was_promisc = dev->flags & IFF_PROMISC;
                kick = 1;
        }
        if (!(dev->flags & IFF_PROMISC)) {
                eexp_setup_filter(dev);
                if (lp->old_mc_count != dev->mc_count) {
                        kick = 1;
                        lp->old_mc_count = dev->mc_count;
                }
        }
        if (kick) {
                unsigned long oj;
                scb_command(dev, SCB_CUsuspend);
                outb(0, ioaddr+SIGNAL_CA);
                outb(0, ioaddr+SIGNAL_CA);
#if 0
                printk("%s: waiting for CU to go suspended\n", dev->name);
#endif
                oj = jiffies;
                while ((SCB_CUstat(scb_status(dev)) == 2) &&
                       (time_before(jiffies, oj + 2000)));
                if (SCB_CUstat(scb_status(dev)) == 2)
                        printk("%s: warning, CU didn't stop\n", dev->name);
                lp->started &= ~(STARTED_CU);
                scb_wrcbl(dev, CONF_LINK);
                scb_command(dev, SCB_CUstart);
                outb(0, ioaddr+SIGNAL_CA);
        }
}


/*
 * MODULE stuff
 */

#ifdef MODULE

#define EEXP_MAX_CARDS     4    /* max number of cards to support */

static struct net_device *dev_eexp[EEXP_MAX_CARDS];
static int irq[EEXP_MAX_CARDS];
static int io[EEXP_MAX_CARDS];

module_param_array(io, int, NULL, 0);
module_param_array(irq, int, NULL, 0);
MODULE_PARM_DESC(io, "EtherExpress 16 I/O base address(es)");
MODULE_PARM_DESC(irq, "EtherExpress 16 IRQ number(s)");
MODULE_LICENSE("GPL");


/* Ideally the user would give us io=, irq= for every card.  If any parameters
 * are specified, we verify and then use them.  If no parameters are given, we
 * autoprobe for one card only.
 */
int __init init_module(void)
{
        struct net_device *dev;
        int this_dev, found = 0;

        for (this_dev = 0; this_dev < EEXP_MAX_CARDS; this_dev++) {
                dev = alloc_etherdev(sizeof(struct net_local));
                dev->irq = irq[this_dev];
                dev->base_addr = io[this_dev];
                if (io[this_dev] == 0) {
                        if (this_dev)
                                break;
                        printk(KERN_NOTICE "eexpress.c: Module autoprobe not recommended, give io=xx.\n");
                }
                if (do_express_probe(dev) == 0) {
                        dev_eexp[this_dev] = dev;
                        found++;
                        continue;
                }
                printk(KERN_WARNING "eexpress.c: Failed to register card at 0x%x.\n", io[this_dev]);
                free_netdev(dev);
                break;
        }
        if (found)
                return 0;
        return -ENXIO;
}

void __exit cleanup_module(void)
{
        int this_dev;

        for (this_dev = 0; this_dev < EEXP_MAX_CARDS; this_dev++) {
                struct net_device *dev = dev_eexp[this_dev];
                if (dev) {
                        unregister_netdev(dev);
                        free_netdev(dev);
                }
        }
}
#endif

/*
 * Local Variables:
 *  c-file-style: "linux"
 *  tab-width: 8
 * End:
 */