Linux-2.6.12-rc2

[safe/jmp/linux-2.6] / drivers / net / tokenring / ibmtr.c

/* ibmtr.c:  A shared-memory IBM Token Ring 16/4 driver for linux
 *
 *      Written 1993 by Mark Swanson and Peter De Schrijver.
 *      This software may be used and distributed according to the terms
 *      of the GNU General Public License, incorporated herein by reference.
 *
 *      This device driver should work with Any IBM Token Ring Card that does
 *      not use DMA.
 *
 *      I used Donald Becker's (becker@scyld.com) device driver work
 *      as a base for most of my initial work.
 *
 *      Changes by Peter De Schrijver
 *              (Peter.Deschrijver@linux.cc.kuleuven.ac.be) :
 *
 *      + changed name to ibmtr.c in anticipation of other tr boards.
 *      + changed reset code and adapter open code.
 *      + added SAP open code.
 *      + a first attempt to write interrupt, transmit and receive routines.
 *
 *      Changes by David W. Morris (dwm@shell.portal.com) :
 *      941003 dwm: - Restructure tok_probe for multiple adapters, devices.
 *      + Add comments, misc reorg for clarity.
 *      + Flatten interrupt handler levels.
 *
 *      Changes by Farzad Farid (farzy@zen.via.ecp.fr)
 *      and Pascal Andre (andre@chimay.via.ecp.fr) (March 9 1995) :
 *      + multi ring support clean up.
 *      + RFC1042 compliance enhanced.
 *
 *      Changes by Pascal Andre (andre@chimay.via.ecp.fr) (September 7 1995) :
 *      + bug correction in tr_tx
 *      + removed redundant information display
 *      + some code reworking
 *
 *      Changes by Michel Lespinasse (walken@via.ecp.fr),
 *      Yann Doussot (doussot@via.ecp.fr) and Pascal Andre (andre@via.ecp.fr)
 *      (February 18, 1996) :
 *      + modified shared memory and mmio access port the driver to
 *        alpha platform (structure access -> readb/writeb)
 *
 *      Changes by Steve Kipisz (bungy@ibm.net or kipisz@vnet.ibm.com)
 *      (January 18 1996):
 *      + swapped WWOR and WWCR in ibmtr.h
 *      + moved some init code from tok_probe into trdev_init.  The
 *        PCMCIA code can call trdev_init to complete initializing
 *        the driver.
 *      + added -DPCMCIA to support PCMCIA
 *      + detecting PCMCIA Card Removal in interrupt handler.  If
 *        ISRP is FF, then a PCMCIA card has been removed
 *        10/2000 Burt needed a new method to avoid crashing the OS
 *
 *      Changes by Paul Norton (pnorton@cts.com) :
 *      + restructured the READ.LOG logic to prevent the transmit SRB
 *        from being rudely overwritten before the transmit cycle is
 *        complete. (August 15 1996)
 *      + completed multiple adapter support. (November 20 1996)
 *      + implemented csum_partial_copy in tr_rx and increased receive 
 *        buffer size and count. Minor fixes. (March 15, 1997)
 *
 *      Changes by Christopher Turcksin <wabbit@rtfc.demon.co.uk>
 *      + Now compiles ok as a module again.
 *
 *      Changes by Paul Norton (pnorton@ieee.org) :
 *      + moved the header manipulation code in tr_tx and tr_rx to
 *        net/802/tr.c. (July 12 1997)
 *      + add retry and timeout on open if cable disconnected. (May 5 1998)
 *      + lifted 2000 byte mtu limit. now depends on shared-RAM size.
 *        May 25 1998)
 *      + can't allocate 2k recv buff at 8k shared-RAM. (20 October 1998)
 *
 *      Changes by Joel Sloan (jjs@c-me.com) :
 *      + disable verbose debug messages by default - to enable verbose
 *        debugging, edit the IBMTR_DEBUG_MESSAGES define below 
 *      
 *      Changes by Mike Phillips <phillim@amtrak.com> :
 *      + Added extra #ifdef's to work with new PCMCIA Token Ring Code.
 *        The PCMCIA code now just sets up the card so it can be recognized
 *        by ibmtr_probe. Also checks allocated memory vs. on-board memory
 *        for correct figure to use.
 *
 *      Changes by Tim Hockin (thockin@isunix.it.ilstu.edu) :
 *      + added spinlocks for SMP sanity (10 March 1999)
 *
 *      Changes by Jochen Friedrich to enable RFC1469 Option 2 multicasting
 *      i.e. using functional address C0 00 00 04 00 00 to transmit and 
 *      receive multicast packets.
 *
 *      Changes by Mike Sullivan (based on original sram patch by Dave Grothe
 *      to support windowing into on adapter shared ram.
 *      i.e. Use LANAID to setup a PnP configuration with 16K RAM. Paging
 *      will shift this 16K window over the entire available shared RAM.
 *
 *      Changes by Peter De Schrijver (p2@mind.be) :
 *      + fixed a problem with PCMCIA card removal
 *
 *      Change by Mike Sullivan et al.:
 *      + added turbo card support. No need to use lanaid to configure
 *      the adapter into isa compatiblity mode.
 *
 *      Changes by Burt Silverman to allow the computer to behave nicely when
 *      a cable is pulled or not in place, or a PCMCIA card is removed hot.
 */

/* change the define of IBMTR_DEBUG_MESSAGES to a nonzero value 
in the event that chatty debug messages are desired - jjs 12/30/98 */

#define IBMTR_DEBUG_MESSAGES 0

#include <linux/module.h>

#ifdef PCMCIA           /* required for ibmtr_cs.c to build */
#undef MODULE           /* yes, really */
#undef ENABLE_PAGING
#else
#define ENABLE_PAGING 1         
#endif

#define FALSE 0
#define TRUE (!FALSE)

/* changes the output format of driver initialization */
#define TR_VERBOSE      0

/* some 95 OS send many non UI frame; this allow removing the warning */
#define TR_FILTERNONUI  1

#include <linux/ioport.h>
#include <linux/netdevice.h>
#include <linux/ip.h>
#include <linux/trdevice.h>
#include <linux/ibmtr.h>

#include <net/checksum.h>

#include <asm/io.h>

#define DPRINTK(format, args...) printk("%s: " format, dev->name , ## args)
#define DPRINTD(format, args...) DummyCall("%s: " format, dev->name , ## args)

/* version and credits */
#ifndef PCMCIA
static char version[] __initdata =
    "\nibmtr.c: v1.3.57   8/ 7/94 Peter De Schrijver and Mark Swanson\n"
    "         v2.1.125 10/20/98 Paul Norton    <pnorton@ieee.org>\n"
    "         v2.2.0   12/30/98 Joel Sloan     <jjs@c-me.com>\n"
    "         v2.2.1   02/08/00 Mike Sullivan  <sullivam@us.ibm.com>\n" 
    "         v2.2.2   07/27/00 Burt Silverman <burts@us.ibm.com>\n" 
    "         v2.4.0   03/01/01 Mike Sullivan <sullivan@us.ibm.com>\n";
#endif

/* this allows displaying full adapter information */

char *channel_def[] __devinitdata = { "ISA", "MCA", "ISA P&P" };

static char pcchannelid[] __devinitdata = {
        0x05, 0x00, 0x04, 0x09,
        0x04, 0x03, 0x04, 0x0f,
        0x03, 0x06, 0x03, 0x01,
        0x03, 0x01, 0x03, 0x00,
        0x03, 0x09, 0x03, 0x09,
        0x03, 0x00, 0x02, 0x00
};

static char mcchannelid[] __devinitdata =  {
        0x04, 0x0d, 0x04, 0x01,
        0x05, 0x02, 0x05, 0x03,
        0x03, 0x06, 0x03, 0x03,
        0x05, 0x08, 0x03, 0x04,
        0x03, 0x05, 0x03, 0x01,
        0x03, 0x08, 0x02, 0x00
};

char __devinit *adapter_def(char type)
{
        switch (type) {
        case 0xF: return "PC Adapter | PC Adapter II | Adapter/A";
        case 0xE: return "16/4 Adapter | 16/4 Adapter/A (long)";
        case 0xD: return "16/4 Adapter/A (short) | 16/4 ISA-16 Adapter";
        case 0xC: return "Auto 16/4 Adapter";
        default: return "adapter (unknown type)";
        };
};

#define TRC_INIT 0x01           /*  Trace initialization & PROBEs */
#define TRC_INITV 0x02          /*  verbose init trace points     */
unsigned char ibmtr_debug_trace = 0;

static int      ibmtr_probe(struct net_device *dev);
static int      ibmtr_probe1(struct net_device *dev, int ioaddr);
static unsigned char get_sram_size(struct tok_info *adapt_info);
static int      trdev_init(struct net_device *dev);
static int      tok_open(struct net_device *dev);
static int      tok_init_card(struct net_device *dev);
void            tok_open_adapter(unsigned long dev_addr);
static void     open_sap(unsigned char type, struct net_device *dev);
static void     tok_set_multicast_list(struct net_device *dev);
static int      tok_send_packet(struct sk_buff *skb, struct net_device *dev);
static int      tok_close(struct net_device *dev);
irqreturn_t tok_interrupt(int irq, void *dev_id, struct pt_regs *regs);
static void     initial_tok_int(struct net_device *dev);
static void     tr_tx(struct net_device *dev);
static void     tr_rx(struct net_device *dev);
void            ibmtr_reset_timer(struct timer_list*tmr,struct net_device *dev);
static void     tok_rerun(unsigned long dev_addr);
void            ibmtr_readlog(struct net_device *dev);
static struct   net_device_stats *tok_get_stats(struct net_device *dev);
int             ibmtr_change_mtu(struct net_device *dev, int mtu);
static void     find_turbo_adapters(int *iolist);

static int ibmtr_portlist[IBMTR_MAX_ADAPTERS+1] __devinitdata = {
        0xa20, 0xa24, 0, 0, 0
};
static int __devinitdata turbo_io[IBMTR_MAX_ADAPTERS] = {0};
static int __devinitdata turbo_irq[IBMTR_MAX_ADAPTERS] = {0};
static int __devinitdata turbo_searched = 0;

#ifndef PCMCIA
static __u32 ibmtr_mem_base __initdata = 0xd0000;
#endif

static void __devinit PrtChanID(char *pcid, short stride)
{
        short i, j;
        for (i = 0, j = 0; i < 24; i++, j += stride)
                printk("%1x", ((int) pcid[j]) & 0x0f);
        printk("\n");
}

static void __devinit HWPrtChanID(void __iomem *pcid, short stride)
{
        short i, j;
        for (i = 0, j = 0; i < 24; i++, j += stride)
                printk("%1x", ((int) readb(pcid + j)) & 0x0f);
        printk("\n");
}

/* We have to ioremap every checked address, because isa_readb is 
 * going away. 
 */

static void __devinit find_turbo_adapters(int *iolist)
{
        int ram_addr;
        int index=0;
        void __iomem *chanid;
        int found_turbo=0;
        unsigned char *tchanid, ctemp;
        int i, j;
        unsigned long jif;
        void __iomem *ram_mapped ;   

        if (turbo_searched == 1) return;
        turbo_searched=1;
        for (ram_addr=0xC0000; ram_addr < 0xE0000; ram_addr+=0x2000) {

                __u32 intf_tbl=0;

                found_turbo=1;
                ram_mapped = ioremap((u32)ram_addr,0x1fff) ; 
                if (ram_mapped==NULL) 
                        continue ; 
                chanid=(CHANNEL_ID + ram_mapped);
                tchanid=pcchannelid;
                ctemp=readb(chanid) & 0x0f;
                if (ctemp != *tchanid) continue;
                for (i=2,j=1; i<=46; i=i+2,j++) {
                        if ((readb(chanid+i) & 0x0f) != tchanid[j]){
                                found_turbo=0;
                                break;
                        }
                }
                if (!found_turbo) continue;

                writeb(0x90, ram_mapped+0x1E01);
                for(i=2; i<0x0f; i++) {
                        writeb(0x00, ram_mapped+0x1E01+i);
                }
                writeb(0x00, ram_mapped+0x1E01);
                for(jif=jiffies+TR_BUSY_INTERVAL; time_before_eq(jiffies,jif););
                intf_tbl=ntohs(readw(ram_mapped+ACA_OFFSET+ACA_RW+WRBR_EVEN));
                if (intf_tbl) {
#if IBMTR_DEBUG_MESSAGES
                        printk("ibmtr::find_turbo_adapters, Turbo found at "
                                "ram_addr %x\n",ram_addr);
                        printk("ibmtr::find_turbo_adapters, interface_table ");
                        for(i=0; i<6; i++) {
                                printk("%x:",readb(ram_addr+intf_tbl+i));
                        }
                        printk("\n");
#endif
                        turbo_io[index]=ntohs(readw(ram_mapped+intf_tbl+4));
                        turbo_irq[index]=readb(ram_mapped+intf_tbl+3);
                        outb(0, turbo_io[index] + ADAPTRESET);
                        for(jif=jiffies+TR_RST_TIME;time_before_eq(jiffies,jif););
                        outb(0, turbo_io[index] + ADAPTRESETREL);
                        index++;
                        continue;
                }
#if IBMTR_DEBUG_MESSAGES 
                printk("ibmtr::find_turbo_adapters, ibmtr card found at"
                        " %x but not a Turbo model\n",ram_addr);
#endif
        iounmap(ram_mapped) ;   
        } /* for */
        for(i=0; i<IBMTR_MAX_ADAPTERS; i++) {
                if(!turbo_io[i]) break;
                for (j=0; j<IBMTR_MAX_ADAPTERS; j++) {
                        if ( iolist[j] && iolist[j] != turbo_io[i]) continue;
                        iolist[j]=turbo_io[i];
                        break;
                }
        }
}

static void ibmtr_cleanup_card(struct net_device *dev)
{
        if (dev->base_addr) {
                outb(0,dev->base_addr+ADAPTRESET);
                
                schedule_timeout(TR_RST_TIME); /* wait 50ms */

                outb(0,dev->base_addr+ADAPTRESETREL);
        }

#ifndef PCMCIA
        free_irq(dev->irq, dev);
        release_region(dev->base_addr, IBMTR_IO_EXTENT);

        { 
                struct tok_info *ti = (struct tok_info *) dev->priv;
                iounmap(ti->mmio);
                iounmap(ti->sram_virt);
        }
#endif          
}

int ibmtr_probe_card(struct net_device *dev)
{
        int err = ibmtr_probe(dev);
        if (!err) {
                err = register_netdev(dev);
                if (err)
                        ibmtr_cleanup_card(dev);
        }
        return err;
}

/****************************************************************************
 *      ibmtr_probe():  Routine specified in the network device structure
 *      to probe for an IBM Token Ring Adapter.  Routine outline:
 *      I.    Interrogate hardware to determine if an adapter exists
 *            and what the speeds and feeds are
 *      II.   Setup data structures to control execution based upon
 *            adapter characteristics.
 *
 *      We expect ibmtr_probe to be called once for each device entry
 *      which references it.
 ****************************************************************************/

static int ibmtr_probe(struct net_device *dev)
{
        int i;
        int base_addr = dev->base_addr;

        if (base_addr && base_addr <= 0x1ff) /* Don't probe at all. */
                return -ENXIO;
        if (base_addr > 0x1ff) { /* Check a single specified location.  */
                if (!ibmtr_probe1(dev, base_addr)) return 0;
                return -ENODEV;
        }
        find_turbo_adapters(ibmtr_portlist);
        for (i = 0; ibmtr_portlist[i]; i++) {
                int ioaddr = ibmtr_portlist[i];

                if (!ibmtr_probe1(dev, ioaddr)) return 0;
        }
        return -ENODEV;
}

/*****************************************************************************/

static int __devinit ibmtr_probe1(struct net_device *dev, int PIOaddr)
{

        unsigned char segment, intr=0, irq=0, i, j, cardpresent=NOTOK, temp=0;
        void __iomem * t_mmio = NULL;
        struct tok_info *ti = dev->priv;
        void __iomem *cd_chanid;
        unsigned char *tchanid, ctemp;
#ifndef PCMCIA
        unsigned char t_irq=0;
        unsigned long timeout;
        static int version_printed;
#endif

        /*    Query the adapter PIO base port which will return
         *    indication of where MMIO was placed. We also have a
         *    coded interrupt number.
         */
        segment = inb(PIOaddr);
        if (segment < 0x40 || segment > 0xe0) {
                /* Out of range values so we'll assume non-existent IO device
                 * but this is not necessarily a problem, esp if a turbo
                 * adapter is being used.  */
#if IBMTR_DEBUG_MESSAGES
                DPRINTK("ibmtr_probe1(): unhappy that inb(0x%X) == 0x%X, "
                        "Hardware Problem?\n",PIOaddr,segment);
#endif
                return -ENODEV;
        }
        /*
         *    Compute the linear base address of the MMIO area
         *    as LINUX doesn't care about segments
         */
        t_mmio = ioremap(((__u32) (segment & 0xfc) << 11) + 0x80000,2048);
        if (!t_mmio) { 
                DPRINTK("Cannot remap mmiobase memory area") ; 
                return -ENODEV ; 
        } 
        intr = segment & 0x03;  /* low bits is coded interrupt # */
        if (ibmtr_debug_trace & TRC_INIT)
                DPRINTK("PIOaddr: %4hx seg/intr: %2x mmio base: %p intr: %d\n"
                                , PIOaddr, (int) segment, t_mmio, (int) intr);

        /*
         *    Now we will compare expected 'channelid' strings with
         *    what we is there to learn of ISA/MCA or not TR card
         */
#ifdef PCMCIA
        iounmap(t_mmio);
        t_mmio = ti->mmio;      /*BMS to get virtual address */
        irq = ti->irq;          /*BMS to display the irq!   */
#endif
        cd_chanid = (CHANNEL_ID + t_mmio);      /* for efficiency */
        tchanid = pcchannelid;
        cardpresent = TR_ISA;   /* try ISA */

        /*    Suboptimize knowing first byte different */
        ctemp = readb(cd_chanid) & 0x0f;
        if (ctemp != *tchanid) {        /* NOT ISA card, try MCA */
                tchanid = mcchannelid;
                cardpresent = TR_MCA;
                if (ctemp != *tchanid)  /* Neither ISA nor MCA */
                        cardpresent = NOTOK;
        }
        if (cardpresent != NOTOK) {
                /*       Know presumed type, try rest of ID */
                for (i = 2, j = 1; i <= 46; i = i + 2, j++) {
                        if( (readb(cd_chanid+i)&0x0f) == tchanid[j]) continue;
                        /* match failed, not TR card */
                        cardpresent = NOTOK;
                        break;
                }
        }
        /* 
         *    If we have an ISA board check for the ISA P&P version,
         *    as it has different IRQ settings 
         */
        if (cardpresent == TR_ISA && (readb(AIPFID + t_mmio) == 0x0e))
                cardpresent = TR_ISAPNP;
        if (cardpresent == NOTOK) {     /* "channel_id" did not match, report */
                if (!(ibmtr_debug_trace & TRC_INIT)) {
#ifndef PCMCIA
                        iounmap(t_mmio);
#endif
                        return -ENODEV;
                }
                DPRINTK( "Channel ID string not found for PIOaddr: %4hx\n",
                                                                PIOaddr);
                DPRINTK("Expected for ISA: ");
                PrtChanID(pcchannelid, 1);
                DPRINTK("           found: ");
/* BMS Note that this can be misleading, when hardware is flaky, because you
   are reading it a second time here. So with my flaky hardware, I'll see my-
   self in this block, with the HW ID matching the ISA ID exactly! */
                HWPrtChanID(cd_chanid, 2);
                DPRINTK("Expected for MCA: ");
                PrtChanID(mcchannelid, 1);
        }
        /* Now, setup some of the pl0 buffers for this driver.. */
        /* If called from PCMCIA, it is already set up, so no need to 
           waste the memory, just use the existing structure */
#ifndef PCMCIA
        ti->mmio = t_mmio;
        for (i = 0; i < IBMTR_MAX_ADAPTERS; i++) {
                if (turbo_io[i] != PIOaddr)
                        continue;
#if IBMTR_DEBUG_MESSAGES 
                printk("ibmtr::tr_probe1, setting PIOaddr %x to Turbo\n",
                       PIOaddr);
#endif
                ti->turbo = 1;
                t_irq = turbo_irq[i];
        }
#endif /* !PCMCIA */
        ti->readlog_pending = 0;
        init_waitqueue_head(&ti->wait_for_reset);

        /* if PCMCIA, the card can be recognized as either TR_ISA or TR_ISAPNP
         * depending which card is inserted.    */
        
#ifndef PCMCIA
        switch (cardpresent) {
        case TR_ISA:
                if (intr == 0) irq = 9; /* irq2 really is irq9 */
                if (intr == 1) irq = 3;
                if (intr == 2) irq = 6;
                if (intr == 3) irq = 7;
                ti->adapter_int_enable = PIOaddr + ADAPTINTREL;
                break;
        case TR_MCA:
                if (intr == 0) irq = 9;
                if (intr == 1) irq = 3;
                if (intr == 2) irq = 10;
                if (intr == 3) irq = 11;
                ti->global_int_enable = 0;
                ti->adapter_int_enable = 0;
                ti->sram_phys=(__u32)(inb(PIOaddr+ADAPTRESETREL) & 0xfe) << 12;
                break;
        case TR_ISAPNP:
                if (!t_irq) {
                        if (intr == 0) irq = 9;
                        if (intr == 1) irq = 3;
                        if (intr == 2) irq = 10;
                        if (intr == 3) irq = 11;
                } else
                        irq=t_irq;
                timeout = jiffies + TR_SPIN_INTERVAL;
                while (!readb(ti->mmio + ACA_OFFSET + ACA_RW + RRR_EVEN)){
                        if (!time_after(jiffies, timeout)) continue;
                        DPRINTK( "Hardware timeout during initialization.\n");
                        iounmap(t_mmio);
                        kfree(ti);
                        return -ENODEV;
                }
                ti->sram_phys =
                     ((__u32)readb(ti->mmio+ACA_OFFSET+ACA_RW+RRR_EVEN)<<12);
                ti->adapter_int_enable = PIOaddr + ADAPTINTREL;
                break;
        } /*end switch (cardpresent) */
#endif  /*not PCMCIA */

        if (ibmtr_debug_trace & TRC_INIT) {     /* just report int */
                DPRINTK("irq=%d", irq);
                printk(", sram_phys=0x%x", ti->sram_phys);
                if(ibmtr_debug_trace&TRC_INITV){ /* full chat in verbose only */
                        DPRINTK(", ti->mmio=%p", ti->mmio);
                        printk(", segment=%02X", segment);
                }
                printk(".\n");
        }

        /* Get hw address of token ring card */
        j = 0;
        for (i = 0; i < 0x18; i = i + 2) {
                /* technical reference states to do this */
                temp = readb(ti->mmio + AIP + i) & 0x0f;
                ti->hw_address[j] = temp;
                if (j & 1)
                        dev->dev_addr[(j / 2)] =
                                ti->hw_address[j]+ (ti->hw_address[j - 1] << 4);
                ++j;
        }
        /* get Adapter type:  'F' = Adapter/A, 'E' = 16/4 Adapter II,... */
        ti->adapter_type = readb(ti->mmio + AIPADAPTYPE);

        /* get Data Rate:  F=4Mb, E=16Mb, D=4Mb & 16Mb ?? */
        ti->data_rate = readb(ti->mmio + AIPDATARATE);

        /* Get Early Token Release support?: F=no, E=4Mb, D=16Mb, C=4&16Mb */
        ti->token_release = readb(ti->mmio + AIPEARLYTOKEN);

        /* How much shared RAM is on adapter ? */
        if (ti->turbo) {
                ti->avail_shared_ram=127;
        } else {
                ti->avail_shared_ram = get_sram_size(ti);/*in 512 byte units */
        }
        /* We need to set or do a bunch of work here based on previous results*/
        /* Support paging?  What sizes?:  F=no, E=16k, D=32k, C=16 & 32k */
        ti->shared_ram_paging = readb(ti->mmio + AIPSHRAMPAGE);

        /* Available DHB  4Mb size:   F=2048, E=4096, D=4464 */
        switch (readb(ti->mmio + AIP4MBDHB)) {
        case 0xe: ti->dhb_size4mb = 4096; break;
        case 0xd: ti->dhb_size4mb = 4464; break;
        default:  ti->dhb_size4mb = 2048; break;
        }

        /* Available DHB 16Mb size:  F=2048, E=4096, D=8192, C=16384, B=17960 */
        switch (readb(ti->mmio + AIP16MBDHB)) {
        case 0xe: ti->dhb_size16mb = 4096; break;
        case 0xd: ti->dhb_size16mb = 8192; break;
        case 0xc: ti->dhb_size16mb = 16384; break;
        case 0xb: ti->dhb_size16mb = 17960; break;
        default:  ti->dhb_size16mb = 2048; break;
        }

        /*    We must figure out how much shared memory space this adapter
         *    will occupy so that if there are two adapters we can fit both
         *    in.  Given a choice, we will limit this adapter to 32K.  The
         *    maximum space will will use for two adapters is 64K so if the
         *    adapter we are working on demands 64K (it also doesn't support
         *    paging), then only one adapter can be supported.  
         */

        /*
         *    determine how much of total RAM is mapped into PC space 
         */
        ti->mapped_ram_size= /*sixteen to onehundredtwentyeight 512byte blocks*/
            1<< ((readb(ti->mmio+ACA_OFFSET+ACA_RW+RRR_ODD) >> 2 & 0x03) + 4);
        ti->page_mask = 0;
        if (ti->turbo)  ti->page_mask=0xf0;
        else if (ti->shared_ram_paging == 0xf);  /* No paging in adapter */
        else {
#ifdef ENABLE_PAGING
                unsigned char pg_size = 0;
                /* BMS:   page size: PCMCIA, use configuration register;
                   ISAPNP, use LANAIDC config tool from www.ibm.com  */
                switch (ti->shared_ram_paging) {
                case 0xf:
                        break;
                case 0xe:
                        ti->page_mask = (ti->mapped_ram_size == 32) ? 0xc0 : 0;
                        pg_size = 32;   /* 16KB page size */
                        break;
                case 0xd:
                        ti->page_mask = (ti->mapped_ram_size == 64) ? 0x80 : 0;
                        pg_size = 64;   /* 32KB page size */
                        break;
                case 0xc:
                        switch (ti->mapped_ram_size) {
                        case 32:
                                ti->page_mask = 0xc0;
                                pg_size = 32;
                                break;
                        case 64:
                                ti->page_mask = 0x80;
                                pg_size = 64;
                                break;
                        }
                        break;
                default:
                        DPRINTK("Unknown shared ram paging info %01X\n",
                                                        ti->shared_ram_paging);
                        iounmap(t_mmio); 
                        kfree(ti);
                        return -ENODEV;
                        break;
                } /*end switch shared_ram_paging */

                if (ibmtr_debug_trace & TRC_INIT)
                        DPRINTK("Shared RAM paging code: %02X, "
                                "mapped RAM size: %dK, shared RAM size: %dK, "
                                "page mask: %02X\n:",
                                ti->shared_ram_paging, ti->mapped_ram_size / 2,
                                ti->avail_shared_ram / 2, ti->page_mask);
#endif  /*ENABLE_PAGING */
        }

#ifndef PCMCIA
        /* finish figuring the shared RAM address */
        if (cardpresent == TR_ISA) {
                static __u32 ram_bndry_mask[] =
                        { 0xffffe000, 0xffffc000, 0xffff8000, 0xffff0000 };
                __u32 new_base, rrr_32, chk_base, rbm;

                rrr_32=readb(ti->mmio+ACA_OFFSET+ACA_RW+RRR_ODD) >> 2 & 0x03;
                rbm = ram_bndry_mask[rrr_32];
                new_base = (ibmtr_mem_base + (~rbm)) & rbm;/* up to boundary */
                chk_base = new_base + (ti->mapped_ram_size << 9);
                if (chk_base > (ibmtr_mem_base + IBMTR_SHARED_RAM_SIZE)) {
                        DPRINTK("Shared RAM for this adapter (%05x) exceeds "
                        "driver limit (%05x), adapter not started.\n",
                        chk_base, ibmtr_mem_base + IBMTR_SHARED_RAM_SIZE);
                        iounmap(t_mmio);
                        kfree(ti);
                        return -ENODEV;
                } else { /* seems cool, record what we have figured out */
                        ti->sram_base = new_base >> 12;
                        ibmtr_mem_base = chk_base;
                }
        }
        else  ti->sram_base = ti->sram_phys >> 12;

        /* The PCMCIA has already got the interrupt line and the io port, 
           so no chance of anybody else getting it - MLP */
        if (request_irq(dev->irq = irq, &tok_interrupt, 0, "ibmtr", dev) != 0) {
                DPRINTK("Could not grab irq %d.  Halting Token Ring driver.\n",
                                        irq);
                iounmap(t_mmio);
                kfree(ti);
                return -ENODEV;
        }
        /*?? Now, allocate some of the PIO PORTs for this driver.. */
        /* record PIOaddr range as busy */
        if (!request_region(PIOaddr, IBMTR_IO_EXTENT, "ibmtr")) {
                DPRINTK("Could not grab PIO range. Halting driver.\n");
                free_irq(dev->irq, dev);
                iounmap(t_mmio);
                kfree(ti);
                return -EBUSY;
        }

        if (!version_printed++) {
                printk(version);
        }
#endif /* !PCMCIA */
        DPRINTK("%s %s found\n",
                channel_def[cardpresent - 1], adapter_def(ti->adapter_type));
        DPRINTK("using irq %d, PIOaddr %hx, %dK shared RAM.\n",
                        irq, PIOaddr, ti->mapped_ram_size / 2);
        DPRINTK("Hardware address : %02X:%02X:%02X:%02X:%02X:%02X\n",
                dev->dev_addr[0], dev->dev_addr[1], dev->dev_addr[2],
                dev->dev_addr[3], dev->dev_addr[4], dev->dev_addr[5]);
        if (ti->page_mask)
                DPRINTK("Shared RAM paging enabled. "
                        "Page size: %uK Shared Ram size %dK\n",
                        ((ti->page_mask^0xff)+1) >>2, ti->avail_shared_ram / 2);
        else
                DPRINTK("Shared RAM paging disabled. ti->page_mask %x\n",
                                                                ti->page_mask);

        /* Calculate the maximum DHB we can use */
        /* two cases where avail_shared_ram doesn't equal mapped_ram_size:
            1. avail_shared_ram is 127 but mapped_ram_size is 128 (typical)
            2. user has configured adapter for less than avail_shared_ram
               but is not using paging (she should use paging, I believe)
        */
        if (!ti->page_mask) {
                ti->avail_shared_ram=
                                min(ti->mapped_ram_size,ti->avail_shared_ram);
        }

        switch (ti->avail_shared_ram) {
        case 16:                /* 8KB shared RAM */
                ti->dhb_size4mb = min(ti->dhb_size4mb, (unsigned short)2048);
                ti->rbuf_len4 = 1032;
                ti->rbuf_cnt4=2;
                ti->dhb_size16mb = min(ti->dhb_size16mb, (unsigned short)2048);
                ti->rbuf_len16 = 1032;
                ti->rbuf_cnt16=2;
                break;
        case 32:                /* 16KB shared RAM */
                ti->dhb_size4mb = min(ti->dhb_size4mb, (unsigned short)4464);
                ti->rbuf_len4 = 1032;
                ti->rbuf_cnt4=4;
                ti->dhb_size16mb = min(ti->dhb_size16mb, (unsigned short)4096);
                ti->rbuf_len16 = 1032;  /*1024 usable */
                ti->rbuf_cnt16=4;
                break;
        case 64:                /* 32KB shared RAM */
                ti->dhb_size4mb = min(ti->dhb_size4mb, (unsigned short)4464);
                ti->rbuf_len4 = 1032;
                ti->rbuf_cnt4=6;
                ti->dhb_size16mb = min(ti->dhb_size16mb, (unsigned short)10240);
                ti->rbuf_len16 = 1032;
                ti->rbuf_cnt16=6;
                break;
        case 127:               /* 63.5KB shared RAM */
                ti->dhb_size4mb = min(ti->dhb_size4mb, (unsigned short)4464);
                ti->rbuf_len4 = 1032;
                ti->rbuf_cnt4=6;
                ti->dhb_size16mb = min(ti->dhb_size16mb, (unsigned short)16384);
                ti->rbuf_len16 = 1032;
                ti->rbuf_cnt16=16;
                break;
        case 128:               /* 64KB   shared RAM */
                ti->dhb_size4mb = min(ti->dhb_size4mb, (unsigned short)4464);
                ti->rbuf_len4 = 1032;
                ti->rbuf_cnt4=6;
                ti->dhb_size16mb = min(ti->dhb_size16mb, (unsigned short)17960);
                ti->rbuf_len16 = 1032;
                ti->rbuf_cnt16=16;
                break;
        default:
                ti->dhb_size4mb = 2048;
                ti->rbuf_len4 = 1032;
                ti->rbuf_cnt4=2;
                ti->dhb_size16mb = 2048;
                ti->rbuf_len16 = 1032;
                ti->rbuf_cnt16=2;
                break;
        }
        /* this formula is not smart enough for the paging case
        ti->rbuf_cnt<x> = (ti->avail_shared_ram * BLOCKSZ - ADAPT_PRIVATE -
                        ARBLENGTH - SSBLENGTH - DLC_MAX_SAP * SAPLENGTH -
                        DLC_MAX_STA * STALENGTH - ti->dhb_size<x>mb * NUM_DHB -
                        SRBLENGTH - ASBLENGTH) / ti->rbuf_len<x>;
        */
        ti->maxmtu16 = (ti->rbuf_len16 - 8) * ti->rbuf_cnt16  - TR_HLEN;
        ti->maxmtu4 = (ti->rbuf_len4 - 8) * ti->rbuf_cnt4 - TR_HLEN;
        /*BMS assuming 18 bytes of Routing Information (usually works) */
        DPRINTK("Maximum Receive Internet Protocol MTU 16Mbps: %d, 4Mbps: %d\n",
                                                     ti->maxmtu16, ti->maxmtu4);

        dev->base_addr = PIOaddr;       /* set the value for device */
        dev->mem_start = ti->sram_base << 12;
        dev->mem_end = dev->mem_start + (ti->mapped_ram_size << 9) - 1;
        trdev_init(dev);
        return 0;   /* Return 0 to indicate we have found a Token Ring card. */
}                               /*ibmtr_probe1() */

/*****************************************************************************/

/* query the adapter for the size of shared RAM  */
/* the function returns the RAM size in units of 512 bytes */

static unsigned char __devinit get_sram_size(struct tok_info *adapt_info)
{
        unsigned char avail_sram_code;
        static unsigned char size_code[] = { 0, 16, 32, 64, 127, 128 };
        /* Adapter gives
           'F' -- use RRR bits 3,2
           'E' -- 8kb   'D' -- 16kb
           'C' -- 32kb  'A' -- 64KB
           'B' - 64KB less 512 bytes at top
           (WARNING ... must zero top bytes in INIT */

        avail_sram_code = 0xf - readb(adapt_info->mmio + AIPAVAILSHRAM);
        if (avail_sram_code) return size_code[avail_sram_code];
        else            /* for code 'F', must compute size from RRR(3,2) bits */
                return 1 <<
                 ((readb(adapt_info->mmio+ACA_OFFSET+ACA_RW+RRR_ODD)>>2&3)+4);
}

/*****************************************************************************/

static int __devinit trdev_init(struct net_device *dev)
{
        struct tok_info *ti = (struct tok_info *) dev->priv;

        SET_PAGE(ti->srb_page);
        ti->open_failure = NO    ;
        dev->open = tok_open;
        dev->stop = tok_close;
        dev->hard_start_xmit = tok_send_packet;
        dev->get_stats = tok_get_stats;
        dev->set_multicast_list = tok_set_multicast_list;
        dev->change_mtu = ibmtr_change_mtu;

        return 0;
}

/*****************************************************************************/

static int tok_init_card(struct net_device *dev)
{
        struct tok_info *ti;
        short PIOaddr;
        unsigned long i;

        PIOaddr = dev->base_addr;
        ti = (struct tok_info *) dev->priv;
        /* Special processing for first interrupt after reset */
        ti->do_tok_int = FIRST_INT;
        /* Reset adapter */
        writeb(~INT_ENABLE, ti->mmio + ACA_OFFSET + ACA_RESET + ISRP_EVEN);
        outb(0, PIOaddr + ADAPTRESET);

        current->state=TASK_UNINTERRUPTIBLE;
        schedule_timeout(TR_RST_TIME); /* wait 50ms */

        outb(0, PIOaddr + ADAPTRESETREL);
#ifdef ENABLE_PAGING
        if (ti->page_mask)
                writeb(SRPR_ENABLE_PAGING,ti->mmio+ACA_OFFSET+ACA_RW+SRPR_EVEN);
#endif
        writeb(INT_ENABLE, ti->mmio + ACA_OFFSET + ACA_SET + ISRP_EVEN);
        i = sleep_on_timeout(&ti->wait_for_reset, 4 * HZ);
        return i? 0 : -EAGAIN;
}

/*****************************************************************************/
static int tok_open(struct net_device *dev)
{
        struct tok_info *ti = (struct tok_info *) dev->priv;
        int i;

        /*the case we were left in a failure state during a previous open */
        if (ti->open_failure == YES) {
                DPRINTK("Last time you were disconnected, how about now?\n");
                printk("You can't insert with an ICS connector half-cocked.\n");
        }

        ti->open_status  = CLOSED; /* CLOSED or OPEN      */
        ti->sap_status   = CLOSED; /* CLOSED or OPEN      */
        ti->open_failure =     NO; /* NO     or YES       */
        ti->open_mode    = MANUAL; /* MANUAL or AUTOMATIC */
        /* 12/2000 not typical Linux, but we can use RUNNING to let us know when
        the network has crapped out or cables are disconnected. Useful because
        the IFF_UP flag stays up the whole time, until ifconfig tr0 down.
        */
        dev->flags &= ~IFF_RUNNING;

        ti->sram_phys &= ~1; /* to reverse what we do in tok_close */
        /* init the spinlock */
        spin_lock_init(&ti->lock);
        init_timer(&ti->tr_timer);
        
        i = tok_init_card(dev);
        if (i) return i;

        while (1){
                tok_open_adapter((unsigned long) dev);
                i= interruptible_sleep_on_timeout(&ti->wait_for_reset, 25 * HZ);
                /* sig catch: estimate opening adapter takes more than .5 sec*/
                if (i>(245*HZ)/10) break; /* fancier than if (i==25*HZ) */
                if (i==0) break;
                if (ti->open_status == OPEN && ti->sap_status==OPEN) {
                        netif_start_queue(dev);
                        DPRINTK("Adapter is up and running\n");
                        return 0;
                }
                current->state=TASK_INTERRUPTIBLE;
                i=schedule_timeout(TR_RETRY_INTERVAL); /* wait 30 seconds */
                if(i!=0) break; /*prob. a signal, like the i>24*HZ case above */
        }
        outb(0, dev->base_addr + ADAPTRESET);/* kill pending interrupts*/
        DPRINTK("TERMINATED via signal\n");     /*BMS useful */
        return -EAGAIN;
}

/*****************************************************************************/

#define COMMAND_OFST             0
#define OPEN_OPTIONS_OFST        8
#define NUM_RCV_BUF_OFST        24
#define RCV_BUF_LEN_OFST        26
#define DHB_LENGTH_OFST         28
#define NUM_DHB_OFST            30
#define DLC_MAX_SAP_OFST        32
#define DLC_MAX_STA_OFST        33

void tok_open_adapter(unsigned long dev_addr)
{
        struct net_device *dev = (struct net_device *) dev_addr;
        struct tok_info *ti;
        int i;

        ti = (struct tok_info *) dev->priv;
        SET_PAGE(ti->init_srb_page); 
        writeb(~SRB_RESP_INT, ti->mmio + ACA_OFFSET + ACA_RESET + ISRP_ODD);
        for (i = 0; i < sizeof(struct dir_open_adapter); i++)
                writeb(0, ti->init_srb + i);
        writeb(DIR_OPEN_ADAPTER, ti->init_srb + COMMAND_OFST);
        writew(htons(OPEN_PASS_BCON_MAC), ti->init_srb + OPEN_OPTIONS_OFST);
        if (ti->ring_speed == 16) {
                writew(htons(ti->dhb_size16mb), ti->init_srb + DHB_LENGTH_OFST);
                writew(htons(ti->rbuf_cnt16), ti->init_srb + NUM_RCV_BUF_OFST);
                writew(htons(ti->rbuf_len16), ti->init_srb + RCV_BUF_LEN_OFST);
        } else {
                writew(htons(ti->dhb_size4mb), ti->init_srb + DHB_LENGTH_OFST);
                writew(htons(ti->rbuf_cnt4), ti->init_srb + NUM_RCV_BUF_OFST);
                writew(htons(ti->rbuf_len4), ti->init_srb + RCV_BUF_LEN_OFST);
        }
        writeb(NUM_DHB,         /* always 2 */ ti->init_srb + NUM_DHB_OFST);
        writeb(DLC_MAX_SAP, ti->init_srb + DLC_MAX_SAP_OFST);
        writeb(DLC_MAX_STA, ti->init_srb + DLC_MAX_STA_OFST);
        ti->srb = ti->init_srb; /* We use this one in the interrupt handler */
        ti->srb_page = ti->init_srb_page;
        DPRINTK("Opening adapter: Xmit bfrs: %d X %d, Rcv bfrs: %d X %d\n",
                readb(ti->init_srb + NUM_DHB_OFST),
                ntohs(readw(ti->init_srb + DHB_LENGTH_OFST)),
                ntohs(readw(ti->init_srb + NUM_RCV_BUF_OFST)),
                ntohs(readw(ti->init_srb + RCV_BUF_LEN_OFST)));
        writeb(INT_ENABLE, ti->mmio + ACA_OFFSET + ACA_SET + ISRP_EVEN);
        writeb(CMD_IN_SRB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
}

/*****************************************************************************/

static void open_sap(unsigned char type, struct net_device *dev)
{
        int i;
        struct tok_info *ti = (struct tok_info *) dev->priv;

        SET_PAGE(ti->srb_page);
        for (i = 0; i < sizeof(struct dlc_open_sap); i++)
                writeb(0, ti->srb + i);

#define MAX_I_FIELD_OFST        14
#define SAP_VALUE_OFST          16
#define SAP_OPTIONS_OFST        17
#define STATION_COUNT_OFST      18

        writeb(DLC_OPEN_SAP, ti->srb + COMMAND_OFST);
        writew(htons(MAX_I_FIELD), ti->srb + MAX_I_FIELD_OFST);
        writeb(SAP_OPEN_IND_SAP | SAP_OPEN_PRIORITY, ti->srb+ SAP_OPTIONS_OFST);
        writeb(SAP_OPEN_STATION_CNT, ti->srb + STATION_COUNT_OFST);
        writeb(type, ti->srb + SAP_VALUE_OFST);
        writeb(CMD_IN_SRB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
}


/*****************************************************************************/

static void tok_set_multicast_list(struct net_device *dev)
{
        struct tok_info *ti = (struct tok_info *) dev->priv;
        struct dev_mc_list *mclist;
        unsigned char address[4];

        int i;

        /*BMS the next line is CRUCIAL or you may be sad when you */
        /*BMS ifconfig tr down or hot unplug a PCMCIA card ??hownowbrowncow*/
        if (/*BMSHELPdev->start == 0 ||*/ ti->open_status != OPEN) return;
        address[0] = address[1] = address[2] = address[3] = 0;
        mclist = dev->mc_list;
        for (i = 0; i < dev->mc_count; i++) {
                address[0] |= mclist->dmi_addr[2];
                address[1] |= mclist->dmi_addr[3];
                address[2] |= mclist->dmi_addr[4];
                address[3] |= mclist->dmi_addr[5];
                mclist = mclist->next;
        }
        SET_PAGE(ti->srb_page);
        for (i = 0; i < sizeof(struct srb_set_funct_addr); i++)
                writeb(0, ti->srb + i);

#define FUNCT_ADDRESS_OFST 6

        writeb(DIR_SET_FUNC_ADDR, ti->srb + COMMAND_OFST);
        for (i = 0; i < 4; i++) 
                writeb(address[i], ti->srb + FUNCT_ADDRESS_OFST + i);
        writeb(CMD_IN_SRB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
#if TR_VERBOSE
        DPRINTK("Setting functional address: ");
        for (i=0;i<4;i++)  printk("%02X ", address[i]);
        printk("\n");
#endif
}

/*****************************************************************************/

#define STATION_ID_OFST 4

static int tok_send_packet(struct sk_buff *skb, struct net_device *dev)
{
        struct tok_info *ti;
        unsigned long flags;
        ti = (struct tok_info *) dev->priv;

        netif_stop_queue(dev);

        /* lock against other CPUs */
        spin_lock_irqsave(&(ti->lock), flags);

        /* Save skb; we'll need it when the adapter asks for the data */
        ti->current_skb = skb;
        SET_PAGE(ti->srb_page);
        writeb(XMIT_UI_FRAME, ti->srb + COMMAND_OFST);
        writew(ti->exsap_station_id, ti->srb + STATION_ID_OFST);
        writeb(CMD_IN_SRB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
        spin_unlock_irqrestore(&(ti->lock), flags);
        dev->trans_start = jiffies;
        return 0;
}

/*****************************************************************************/

static int tok_close(struct net_device *dev)
{
        struct tok_info *ti = (struct tok_info *) dev->priv;

        /* Important for PCMCIA hot unplug, otherwise, we'll pull the card, */
        /* unloading the module from memory, and then if a timer pops, ouch */
        del_timer_sync(&ti->tr_timer);
        outb(0, dev->base_addr + ADAPTRESET);
        ti->sram_phys |= 1;
        ti->open_status = CLOSED;

        netif_stop_queue(dev);
        DPRINTK("Adapter is closed.\n");
        return 0;
}

/*****************************************************************************/

#define RETCODE_OFST            2
#define OPEN_ERROR_CODE_OFST    6
#define ASB_ADDRESS_OFST        8
#define SRB_ADDRESS_OFST        10
#define ARB_ADDRESS_OFST        12
#define SSB_ADDRESS_OFST        14

static char *printphase[]= {"Lobe media test","Physical insertion",
              "Address verification","Roll call poll","Request Parameters"};
static char *printerror[]={"Function failure","Signal loss","Reserved",
                "Frequency error","Timeout","Ring failure","Ring beaconing",
                "Duplicate node address",
                "Parameter request-retry count exceeded","Remove received",
                "IMPL force received","Duplicate modifier",
                "No monitor detected","Monitor contention failed for RPL"};

static void __iomem *map_address(struct tok_info *ti, unsigned index, __u8 *page)
{
        if (ti->page_mask) {
                *page = (index >> 8) & ti->page_mask;
                index &= ~(ti->page_mask << 8);
        }
        return ti->sram_virt + index;
}

void dir_open_adapter (struct net_device *dev)
{
        struct tok_info *ti = (struct tok_info *) dev->priv;
        unsigned char ret_code;
        __u16 err;

        ti->srb = map_address(ti,
                ntohs(readw(ti->init_srb + SRB_ADDRESS_OFST)),
                &ti->srb_page);
        ti->ssb = map_address(ti,
                ntohs(readw(ti->init_srb + SSB_ADDRESS_OFST)),
                &ti->ssb_page);
        ti->arb = map_address(ti,
                ntohs(readw(ti->init_srb + ARB_ADDRESS_OFST)),
                &ti->arb_page);
        ti->asb = map_address(ti,
                ntohs(readw(ti->init_srb + ASB_ADDRESS_OFST)),
                &ti->asb_page);
        ti->current_skb = NULL;
        ret_code = readb(ti->init_srb + RETCODE_OFST);
        err = ntohs(readw(ti->init_srb + OPEN_ERROR_CODE_OFST));
        if (!ret_code) {
                ti->open_status = OPEN; /* TR adapter is now available */
                if (ti->open_mode == AUTOMATIC) {
                        DPRINTK("Adapter reopened.\n");
                }
                writeb(~SRB_RESP_INT, ti->mmio+ACA_OFFSET+ACA_RESET+ISRP_ODD);
                open_sap(EXTENDED_SAP, dev);
                return;
        }
        ti->open_failure = YES;
        if (ret_code == 7){
               if (err == 0x24) {
                        if (!ti->auto_speedsave) {
                                DPRINTK("Open failed: Adapter speed must match "
                                 "ring speed if Automatic Ring Speed Save is "
                                 "disabled.\n");
                                ti->open_action = FAIL;
                        }else
                                DPRINTK("Retrying open to adjust to "
                                        "ring speed, ");
                } else if (err == 0x2d) {
                        DPRINTK("Physical Insertion: No Monitor Detected, ");
                        printk("retrying after %ds delay...\n",
                                        TR_RETRY_INTERVAL/HZ);
                } else if (err == 0x11) {
                        DPRINTK("Lobe Media Function Failure (0x11), ");
                        printk(" retrying after %ds delay...\n",
                                        TR_RETRY_INTERVAL/HZ);
                } else {
                        char **prphase = printphase;
                        char **prerror = printerror;
                        DPRINTK("TR Adapter misc open failure, error code = ");
                        printk("0x%x, Phase: %s, Error: %s\n",
                                err, prphase[err/16 -1], prerror[err%16 -1]);
                        printk(" retrying after %ds delay...\n",
                                        TR_RETRY_INTERVAL/HZ);
                }
        } else DPRINTK("open failed: ret_code = %02X..., ", ret_code);
        if (ti->open_action != FAIL) {
                if (ti->open_mode==AUTOMATIC){
                        ti->open_action = REOPEN;
                        ibmtr_reset_timer(&(ti->tr_timer), dev);
                        return;
                }
                wake_up(&ti->wait_for_reset);
                return;
        }
        DPRINTK("FAILURE, CAPUT\n");
}

/******************************************************************************/

irqreturn_t tok_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
        unsigned char status;
        /*  unsigned char status_even ; */
        struct tok_info *ti;
        struct net_device *dev;
#ifdef ENABLE_PAGING
        unsigned char save_srpr;
#endif

        dev = dev_id;
#if TR_VERBOSE
        DPRINTK("Int from tok_driver, dev : %p irq%d regs=%p\n", dev,irq,regs);
#endif
        ti = (struct tok_info *) dev->priv;
        if (ti->sram_phys & 1)
                return IRQ_NONE;         /* PCMCIA card extraction flag */
        spin_lock(&(ti->lock));
#ifdef ENABLE_PAGING
        save_srpr = readb(ti->mmio + ACA_OFFSET + ACA_RW + SRPR_EVEN);
#endif

        /* Disable interrupts till processing is finished */
        writeb((~INT_ENABLE), ti->mmio + ACA_OFFSET + ACA_RESET + ISRP_EVEN);

        /* Reset interrupt for ISA boards */
        if (ti->adapter_int_enable)
                outb(0, ti->adapter_int_enable);
        else /* used for PCMCIA cards */
                outb(0, ti->global_int_enable);
        if (ti->do_tok_int == FIRST_INT){
                initial_tok_int(dev);
#ifdef ENABLE_PAGING
                writeb(save_srpr, ti->mmio + ACA_OFFSET + ACA_RW + SRPR_EVEN);
#endif
                spin_unlock(&(ti->lock));
                return IRQ_HANDLED;
        }
        /*  Begin interrupt handler HERE inline to avoid the extra
            levels of logic and call depth for the original solution. */
        status = readb(ti->mmio + ACA_OFFSET + ACA_RW + ISRP_ODD);
        /*BMSstatus_even = readb (ti->mmio + ACA_OFFSET + ACA_RW + ISRP_EVEN) */
        /*BMSdebugprintk("tok_interrupt: ISRP_ODD = 0x%x ISRP_EVEN = 0x%x\n", */
        /*BMS                                       status,status_even);      */

        if (status & ADAP_CHK_INT) {
                int i;
                void __iomem *check_reason;
                __u8 check_reason_page = 0;
                check_reason = map_address(ti,
                        ntohs(readw(ti->mmio+ ACA_OFFSET+ACA_RW + WWCR_EVEN)),
                        &check_reason_page);
                SET_PAGE(check_reason_page);

                DPRINTK("Adapter check interrupt\n");
                DPRINTK("8 reason bytes follow: ");
                for (i = 0; i < 8; i++, check_reason++)
                        printk("%02X ", (int) readb(check_reason));
                printk("\n");
                writeb(~ADAP_CHK_INT, ti->mmio+ ACA_OFFSET+ACA_RESET+ ISRP_ODD);
                status = readb(ti->mmio + ACA_OFFSET + ACA_RW + ISRA_EVEN);
                DPRINTK("ISRA_EVEN == 0x02%x\n",status);
                ti->open_status = CLOSED;
                ti->sap_status  = CLOSED;
                ti->open_mode   = AUTOMATIC;
                dev->flags &= ~IFF_RUNNING;
                netif_stop_queue(dev);
                ti->open_action = RESTART;
                outb(0, dev->base_addr + ADAPTRESET);
                ibmtr_reset_timer(&(ti->tr_timer), dev);/*BMS try to reopen*/
                spin_unlock(&(ti->lock));
                return IRQ_HANDLED;
        }
        if (readb(ti->mmio + ACA_OFFSET + ACA_RW + ISRP_EVEN)
                & (TCR_INT | ERR_INT | ACCESS_INT)) {
                DPRINTK("adapter error: ISRP_EVEN : %02x\n",
                        (int)readb(ti->mmio+ ACA_OFFSET + ACA_RW + ISRP_EVEN));
                writeb(~(TCR_INT | ERR_INT | ACCESS_INT),
                        ti->mmio + ACA_OFFSET + ACA_RESET + ISRP_EVEN);
                status= readb(ti->mmio+ ACA_OFFSET + ACA_RW + ISRA_EVEN);/*BMS*/
                DPRINTK("ISRA_EVEN == 0x02%x\n",status);/*BMS*/
                writeb(INT_ENABLE, ti->mmio + ACA_OFFSET + ACA_SET + ISRP_EVEN);
#ifdef ENABLE_PAGING
                writeb(save_srpr, ti->mmio + ACA_OFFSET + ACA_RW + SRPR_EVEN);
#endif
                spin_unlock(&(ti->lock));
                return IRQ_HANDLED;
        }
        if (status & SRB_RESP_INT) {    /* SRB response */
                SET_PAGE(ti->srb_page);
#if TR_VERBOSE
                DPRINTK("SRB resp: cmd=%02X rsp=%02X\n",
                                readb(ti->srb), readb(ti->srb + RETCODE_OFST));
#endif
                switch (readb(ti->srb)) {       /* SRB command check */
                case XMIT_DIR_FRAME:{
                        unsigned char xmit_ret_code;
                        xmit_ret_code = readb(ti->srb + RETCODE_OFST);
                        if (xmit_ret_code == 0xff) break;
                        DPRINTK("error on xmit_dir_frame request: %02X\n",
                                                                xmit_ret_code);
                        if (ti->current_skb) {
                                dev_kfree_skb_irq(ti->current_skb);
                                ti->current_skb = NULL;
                        }
                        /*dev->tbusy = 0;*/
                        netif_wake_queue(dev);
                        if (ti->readlog_pending)
                                ibmtr_readlog(dev);
                        break;
                }
                case XMIT_UI_FRAME:{
                        unsigned char xmit_ret_code;

                        xmit_ret_code = readb(ti->srb + RETCODE_OFST);
                        if (xmit_ret_code == 0xff) break;
                        DPRINTK("error on xmit_ui_frame request: %02X\n",
                                                                xmit_ret_code);
                        if (ti->current_skb) {
                                dev_kfree_skb_irq(ti->current_skb);
                                ti->current_skb = NULL;
                        }
                        netif_wake_queue(dev);
                        if (ti->readlog_pending)
                                ibmtr_readlog(dev);
                        break;
                }
                case DIR_OPEN_ADAPTER:
                        dir_open_adapter(dev);
                        break;
                case DLC_OPEN_SAP:
                        if (readb(ti->srb + RETCODE_OFST)) {
                                DPRINTK("open_sap failed: ret_code = %02X, "
                                        "retrying\n",
                                        (int) readb(ti->srb + RETCODE_OFST));
                                ti->open_action = REOPEN;
                                ibmtr_reset_timer(&(ti->tr_timer), dev);
                                break;
                        }
                        ti->exsap_station_id = readw(ti->srb + STATION_ID_OFST);
                        ti->sap_status = OPEN;/* TR adapter is now available */
                        if (ti->open_mode==MANUAL){
                                wake_up(&ti->wait_for_reset);
                                break;
                        }
                        netif_wake_queue(dev);
                        dev->flags |= IFF_RUNNING;/*BMS 12/2000*/
                        break;
                case DIR_INTERRUPT:
                case DIR_MOD_OPEN_PARAMS:
                case DIR_SET_GRP_ADDR:
                case DIR_SET_FUNC_ADDR:
                case DLC_CLOSE_SAP:
                        if (readb(ti->srb + RETCODE_OFST))
                                DPRINTK("error on %02X: %02X\n",
                                        (int) readb(ti->srb + COMMAND_OFST),
                                        (int) readb(ti->srb + RETCODE_OFST));
                        break;
                case DIR_READ_LOG:
                        if (readb(ti->srb + RETCODE_OFST)){
                                DPRINTK("error on dir_read_log: %02X\n",
                                        (int) readb(ti->srb + RETCODE_OFST));
                                netif_wake_queue(dev);
                                break;
                        }
#if IBMTR_DEBUG_MESSAGES

#define LINE_ERRORS_OFST                 0
#define INTERNAL_ERRORS_OFST             1
#define BURST_ERRORS_OFST                2
#define AC_ERRORS_OFST                   3
#define ABORT_DELIMITERS_OFST            4
#define LOST_FRAMES_OFST                 6
#define RECV_CONGEST_COUNT_OFST          7
#define FRAME_COPIED_ERRORS_OFST         8
#define FREQUENCY_ERRORS_OFST            9
#define TOKEN_ERRORS_OFST               10

                        DPRINTK("Line errors %02X, Internal errors %02X, "
                        "Burst errors %02X\n" "A/C errors %02X, "
                        "Abort delimiters %02X, Lost frames %02X\n"
                        "Receive congestion count %02X, "
                        "Frame copied errors %02X\nFrequency errors %02X, "
                        "Token errors %02X\n",
                        (int) readb(ti->srb + LINE_ERRORS_OFST),
                        (int) readb(ti->srb + INTERNAL_ERRORS_OFST),
                        (int) readb(ti->srb + BURST_ERRORS_OFST),
                        (int) readb(ti->srb + AC_ERRORS_OFST),
                        (int) readb(ti->srb + ABORT_DELIMITERS_OFST),
                        (int) readb(ti->srb + LOST_FRAMES_OFST),
                        (int) readb(ti->srb + RECV_CONGEST_COUNT_OFST),
                        (int) readb(ti->srb + FRAME_COPIED_ERRORS_OFST),
                        (int) readb(ti->srb + FREQUENCY_ERRORS_OFST),
                        (int) readb(ti->srb + TOKEN_ERRORS_OFST));
#endif
                        netif_wake_queue(dev);
                        break;
                default:
                        DPRINTK("Unknown command %02X encountered\n",
                                                (int) readb(ti->srb));
                }       /* end switch SRB command check */
                writeb(~SRB_RESP_INT, ti->mmio+ ACA_OFFSET+ACA_RESET+ ISRP_ODD);
        }       /* if SRB response */
        if (status & ASB_FREE_INT) {    /* ASB response */
                SET_PAGE(ti->asb_page);
#if TR_VERBOSE
                DPRINTK("ASB resp: cmd=%02X\n", readb(ti->asb));
#endif

                switch (readb(ti->asb)) {       /* ASB command check */
                case REC_DATA:
                case XMIT_UI_FRAME:
                case XMIT_DIR_FRAME:
                        break;
                default:
                        DPRINTK("unknown command in asb %02X\n",
                                                (int) readb(ti->asb));
                }       /* switch ASB command check */
                if (readb(ti->asb + 2) != 0xff) /* checks ret_code */
                        DPRINTK("ASB error %02X in cmd %02X\n",
                                (int) readb(ti->asb + 2), (int) readb(ti->asb));
                writeb(~ASB_FREE_INT, ti->mmio+ ACA_OFFSET+ACA_RESET+ ISRP_ODD);
        }       /* if ASB response */

#define STATUS_OFST             6
#define NETW_STATUS_OFST        6

        if (status & ARB_CMD_INT) {     /* ARB response */
                SET_PAGE(ti->arb_page);
#if TR_VERBOSE
                DPRINTK("ARB resp: cmd=%02X\n", readb(ti->arb));
#endif

                switch (readb(ti->arb)) {       /* ARB command check */
                case DLC_STATUS:
                        DPRINTK("DLC_STATUS new status: %02X on station %02X\n",
                                ntohs(readw(ti->arb + STATUS_OFST)),
                                ntohs(readw(ti->arb+ STATION_ID_OFST)));
                        break;
                case REC_DATA:
                        tr_rx(dev);
                        break;
                case RING_STAT_CHANGE:{
                        unsigned short ring_status;
                        ring_status= ntohs(readw(ti->arb + NETW_STATUS_OFST));
                        if (ibmtr_debug_trace & TRC_INIT)
                                DPRINTK("Ring Status Change...(0x%x)\n",
                                                                ring_status);
                        if(ring_status& (REMOVE_RECV|AUTO_REMOVAL|LOBE_FAULT)){
                                netif_stop_queue(dev);
                                dev->flags &= ~IFF_RUNNING;/*not typical Linux*/
                                DPRINTK("Remove received, or Auto-removal error"
                                        ", or Lobe fault\n");
                                DPRINTK("We'll try to reopen the closed adapter"
                                        " after a %d second delay.\n",
                                                TR_RETRY_INTERVAL/HZ);
                                /*I was confused: I saw the TR reopening but */
                                /*forgot:with an RJ45 in an RJ45/ICS adapter */
                                /*but adapter not in the ring, the TR will   */
                                /* open, and then soon close and come here.  */
                                ti->open_mode = AUTOMATIC;
                                ti->open_status = CLOSED; /*12/2000 BMS*/
                                ti->open_action = REOPEN;
                                ibmtr_reset_timer(&(ti->tr_timer), dev);
                        } else if (ring_status & LOG_OVERFLOW) {
                                if(netif_queue_stopped(dev))
                                        ti->readlog_pending = 1;
                                else
                                        ibmtr_readlog(dev);
                        }
                        break;
                }
                case XMIT_DATA_REQ:
                        tr_tx(dev);
                        break;
                default:
                        DPRINTK("Unknown command %02X in arb\n",
                                                (int) readb(ti->arb));
                        break;
                }       /* switch ARB command check */
                writeb(~ARB_CMD_INT, ti->mmio+ ACA_OFFSET+ACA_RESET + ISRP_ODD);
                writeb(ARB_FREE, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
        }       /* if ARB response */
        if (status & SSB_RESP_INT) {    /* SSB response */
                unsigned char retcode;
                SET_PAGE(ti->ssb_page);
#if TR_VERBOSE
                DPRINTK("SSB resp: cmd=%02X rsp=%02X\n",
                                readb(ti->ssb), readb(ti->ssb + 2));
#endif

                switch (readb(ti->ssb)) {       /* SSB command check */
                case XMIT_DIR_FRAME:
                case XMIT_UI_FRAME:
                        retcode = readb(ti->ssb + 2);
                        if (retcode && (retcode != 0x22))/* checks ret_code */
                                DPRINTK("xmit ret_code: %02X xmit error code: "
                                        "%02X\n",
                                        (int)retcode, (int)readb(ti->ssb + 6));
                        else
                                ti->tr_stats.tx_packets++;
                        break;
                case XMIT_XID_CMD:
                        DPRINTK("xmit xid ret_code: %02X\n",
                                                (int) readb(ti->ssb + 2));
                default:
                        DPRINTK("Unknown command %02X in ssb\n",
                                                (int) readb(ti->ssb));
                }       /* SSB command check */
                writeb(~SSB_RESP_INT, ti->mmio+ ACA_OFFSET+ACA_RESET+ ISRP_ODD);
                writeb(SSB_FREE, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
        }       /* if SSB response */
#ifdef ENABLE_PAGING
        writeb(save_srpr, ti->mmio + ACA_OFFSET + ACA_RW + SRPR_EVEN);
#endif
        writeb(INT_ENABLE, ti->mmio + ACA_OFFSET + ACA_SET + ISRP_EVEN);
        spin_unlock(&(ti->lock));
        return IRQ_HANDLED;
}                               /*tok_interrupt */

/*****************************************************************************/

#define INIT_STATUS_OFST        1
#define INIT_STATUS_2_OFST      2
#define ENCODED_ADDRESS_OFST    8

static void initial_tok_int(struct net_device *dev)
{

        __u32 encoded_addr, hw_encoded_addr;
        struct tok_info *ti;
        unsigned char init_status; /*BMS 12/2000*/

        ti = (struct tok_info *) dev->priv;

        ti->do_tok_int = NOT_FIRST;

        /* we assign the shared-ram address for ISA devices */
        writeb(ti->sram_base, ti->mmio + ACA_OFFSET + ACA_RW + RRR_EVEN);
#ifndef PCMCIA
        ti->sram_virt = ioremap(((__u32)ti->sram_base << 12), ti->avail_shared_ram);
#endif
        ti->init_srb = map_address(ti,
                ntohs(readw(ti->mmio + ACA_OFFSET + WRBR_EVEN)),
                &ti->init_srb_page);
        if (ti->page_mask && ti->avail_shared_ram == 127) {
                void __iomem *last_512;
                __u8 last_512_page=0;
                int i;
                last_512 = map_address(ti, 0xfe00, &last_512_page);
                /* initialize high section of ram (if necessary) */
                SET_PAGE(last_512_page);
                for (i = 0; i < 512; i++)
                        writeb(0, last_512 + i);
        }
        SET_PAGE(ti->init_srb_page);

#if TR_VERBOSE
        {
        int i;

        DPRINTK("ti->init_srb_page=0x%x\n", ti->init_srb_page);
        DPRINTK("init_srb(%p):", ti->init_srb );
        for (i = 0; i < 20; i++)
                printk("%02X ", (int) readb(ti->init_srb + i));
        printk("\n");
        }
#endif

        hw_encoded_addr = readw(ti->init_srb + ENCODED_ADDRESS_OFST);
        encoded_addr = ntohs(hw_encoded_addr);
        init_status= /*BMS 12/2000 check for shallow mode possibility (Turbo)*/
        readb(ti->init_srb+offsetof(struct srb_init_response,init_status));
        /*printk("Initial interrupt: init_status= 0x%02x\n",init_status);*/
        ti->ring_speed = init_status & 0x01 ? 16 : 4;
        DPRINTK("Initial interrupt : %d Mbps, shared RAM base %08x.\n",
                                ti->ring_speed, (unsigned int)dev->mem_start);
        ti->auto_speedsave=readb(ti->init_srb+INIT_STATUS_2_OFST)&4?TRUE:FALSE;

        if (ti->open_mode == MANUAL)    wake_up(&ti->wait_for_reset);
        else                            tok_open_adapter((unsigned long)dev);
        
} /*initial_tok_int() */

/*****************************************************************************/

#define CMD_CORRELATE_OFST      1
#define DHB_ADDRESS_OFST        6

#define FRAME_LENGTH_OFST       6
#define HEADER_LENGTH_OFST      8
#define RSAP_VALUE_OFST         9

static void tr_tx(struct net_device *dev)
{
        struct tok_info *ti = (struct tok_info *) dev->priv;
        struct trh_hdr *trhdr = (struct trh_hdr *) ti->current_skb->data;
        unsigned int hdr_len;
        __u32 dhb=0,dhb_base;
        void __iomem *dhbuf = NULL;
        unsigned char xmit_command;
        int i,dhb_len=0x4000,src_len,src_offset;
        struct trllc *llc;
        struct srb_xmit xsrb;
        __u8 dhb_page = 0;
        __u8 llc_ssap;

        SET_PAGE(ti->asb_page);

        if (readb(ti->asb+RETCODE_OFST) != 0xFF) DPRINTK("ASB not free !!!\n");

        /* in providing the transmit interrupts, is telling us it is ready for
           data and providing a shared memory address for us to stuff with data.
           Here we compute the effective address where we will place data.
        */
        SET_PAGE(ti->arb_page);
        dhb=dhb_base=ntohs(readw(ti->arb + DHB_ADDRESS_OFST));
        if (ti->page_mask) {
                dhb_page = (dhb_base >> 8) & ti->page_mask;
                dhb=dhb_base & ~(ti->page_mask << 8);
        }
        dhbuf = ti->sram_virt + dhb;

        /* Figure out the size of the 802.5 header */
        if (!(trhdr->saddr[0] & 0x80))  /* RIF present? */
                hdr_len = sizeof(struct trh_hdr) - TR_MAXRIFLEN;
        else
                hdr_len = ((ntohs(trhdr->rcf) & TR_RCF_LEN_MASK) >> 8)
                    + sizeof(struct trh_hdr) - TR_MAXRIFLEN;

        llc = (struct trllc *) (ti->current_skb->data + hdr_len);

        llc_ssap = llc->ssap;
        SET_PAGE(ti->srb_page);
        memcpy_fromio(&xsrb, ti->srb, sizeof(xsrb));
        SET_PAGE(ti->asb_page);
        xmit_command = xsrb.command;

        writeb(xmit_command, ti->asb + COMMAND_OFST);
        writew(xsrb.station_id, ti->asb + STATION_ID_OFST);
        writeb(llc_ssap, ti->asb + RSAP_VALUE_OFST);
        writeb(xsrb.cmd_corr, ti->asb + CMD_CORRELATE_OFST);
        writeb(0, ti->asb + RETCODE_OFST);
        if ((xmit_command == XMIT_XID_CMD) || (xmit_command == XMIT_TEST_CMD)) {
                writew(htons(0x11), ti->asb + FRAME_LENGTH_OFST);
                writeb(0x0e, ti->asb + HEADER_LENGTH_OFST);
                SET_PAGE(dhb_page);
                writeb(AC, dhbuf);
                writeb(LLC_FRAME, dhbuf + 1);
                for (i = 0; i < TR_ALEN; i++)
                        writeb((int) 0x0FF, dhbuf + i + 2);
                for (i = 0; i < TR_ALEN; i++)
                        writeb(0, dhbuf + i + TR_ALEN + 2);
                writeb(RESP_IN_ASB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
                return;
        }
        /*
         *    the token ring packet is copied from sk_buff to the adapter
         *    buffer identified in the command data received with the interrupt.
         */
        writeb(hdr_len, ti->asb + HEADER_LENGTH_OFST);
        writew(htons(ti->current_skb->len), ti->asb + FRAME_LENGTH_OFST);
        src_len=ti->current_skb->len;
        src_offset=0;
        dhb=dhb_base;
        while(1) {
                if (ti->page_mask) {
                        dhb_page=(dhb >> 8) & ti->page_mask;
                        dhb=dhb & ~(ti->page_mask << 8);
                        dhb_len=0x4000-dhb; /* remaining size of this page */
                }
                dhbuf = ti->sram_virt + dhb;
                SET_PAGE(dhb_page);
                if (src_len > dhb_len) {
                        memcpy_toio(dhbuf,&ti->current_skb->data[src_offset],
                                        dhb_len);
                        src_len -= dhb_len;
                        src_offset += dhb_len;
                        dhb_base+=dhb_len;
                        dhb=dhb_base;
                        continue;
                }
                memcpy_toio(dhbuf, &ti->current_skb->data[src_offset], src_len);
                break;
        }
        writeb(RESP_IN_ASB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
        ti->tr_stats.tx_bytes += ti->current_skb->len;
        dev_kfree_skb_irq(ti->current_skb);
        ti->current_skb = NULL;
        netif_wake_queue(dev);
        if (ti->readlog_pending)
                ibmtr_readlog(dev);
}                               /*tr_tx */

/*****************************************************************************/


#define RECEIVE_BUFFER_OFST     6
#define LAN_HDR_LENGTH_OFST     8
#define DLC_HDR_LENGTH_OFST     9

#define DSAP_OFST               0
#define SSAP_OFST               1
#define LLC_OFST                2
#define PROTID_OFST             3
#define ETHERTYPE_OFST          6

static void tr_rx(struct net_device *dev)
{
        struct tok_info *ti = (struct tok_info *) dev->priv;
        __u32 rbuffer;
        void __iomem *rbuf, *rbufdata, *llc;
        __u8 rbuffer_page = 0;
        unsigned char *data;
        unsigned int rbuffer_len, lan_hdr_len, hdr_len, ip_len, length;
        unsigned char dlc_hdr_len;
        struct sk_buff *skb;
        unsigned int skb_size = 0;
        int IPv4_p = 0;
        unsigned int chksum = 0;
        struct iphdr *iph;
        struct arb_rec_req rarb;

        SET_PAGE(ti->arb_page);
        memcpy_fromio(&rarb, ti->arb, sizeof(rarb));
        rbuffer = ntohs(rarb.rec_buf_addr) ;
        rbuf = map_address(ti, rbuffer, &rbuffer_page);

        SET_PAGE(ti->asb_page);

        if (readb(ti->asb + RETCODE_OFST) !=0xFF) DPRINTK("ASB not free !!!\n");

        writeb(REC_DATA, ti->asb + COMMAND_OFST);
        writew(rarb.station_id, ti->asb + STATION_ID_OFST);
        writew(rarb.rec_buf_addr, ti->asb + RECEIVE_BUFFER_OFST);

        lan_hdr_len = rarb.lan_hdr_len;
        if (lan_hdr_len > sizeof(struct trh_hdr)) {
                DPRINTK("Linux cannot handle greater than 18 bytes RIF\n");
                return;
        }                       /*BMS I added this above just to be very safe */
        dlc_hdr_len = readb(ti->arb + DLC_HDR_LENGTH_OFST);
        hdr_len = lan_hdr_len + sizeof(struct trllc) + sizeof(struct iphdr);

        SET_PAGE(rbuffer_page);
        llc = rbuf + offsetof(struct rec_buf, data) + lan_hdr_len;

#if TR_VERBOSE
        DPRINTK("offsetof data: %02X lan_hdr_len: %02X\n",
        (__u32) offsetof(struct rec_buf, data), (unsigned int) lan_hdr_len);
        DPRINTK("llc: %08X rec_buf_addr: %04X dev->mem_start: %lX\n",
                llc, ntohs(rarb.rec_buf_addr), dev->mem_start);
        DPRINTK("dsap: %02X, ssap: %02X, llc: %02X, protid: %02X%02X%02X, "
                "ethertype: %04X\n",
                (int) readb(llc + DSAP_OFST), (int) readb(llc + SSAP_OFST),
                (int) readb(llc + LLC_OFST), (int) readb(llc + PROTID_OFST),
                (int) readb(llc+PROTID_OFST+1),(int)readb(llc+PROTID_OFST + 2),
                (int) ntohs(readw(llc + ETHERTYPE_OFST)));
#endif
        if (readb(llc + offsetof(struct trllc, llc)) != UI_CMD) {
                SET_PAGE(ti->asb_page);
                writeb(DATA_LOST, ti->asb + RETCODE_OFST);
                ti->tr_stats.rx_dropped++;
                writeb(RESP_IN_ASB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
                return;
        }
        length = ntohs(rarb.frame_len);
        if (readb(llc + DSAP_OFST) == EXTENDED_SAP &&
           readb(llc + SSAP_OFST) == EXTENDED_SAP &&
                length >= hdr_len)      IPv4_p = 1;
#if TR_VERBOSE
#define SADDR_OFST      8
#define DADDR_OFST      2

        if (!IPv4_p) {

                void __iomem *trhhdr = rbuf + offsetof(struct rec_buf, data);

                DPRINTK("Probably non-IP frame received.\n");
                DPRINTK("ssap: %02X dsap: %02X "
                        "saddr: %02X:%02X:%02X:%02X:%02X:%02X "
                        "daddr: %02X:%02X:%02X:%02X:%02X:%02X\n",
                        readb(llc + SSAP_OFST), readb(llc + DSAP_OFST),
                        readb(trhhdr+SADDR_OFST), readb(trhhdr+ SADDR_OFST+1),
                        readb(trhhdr+SADDR_OFST+2), readb(trhhdr+SADDR_OFST+3),
                        readb(trhhdr+SADDR_OFST+4), readb(trhhdr+SADDR_OFST+5),
                        readb(trhhdr+DADDR_OFST), readb(trhhdr+DADDR_OFST + 1),
                        readb(trhhdr+DADDR_OFST+2), readb(trhhdr+DADDR_OFST+3),
                        readb(trhhdr+DADDR_OFST+4), readb(trhhdr+DADDR_OFST+5));
        }
#endif

        /*BMS handle the case she comes in with few hops but leaves with many */
        skb_size=length-lan_hdr_len+sizeof(struct trh_hdr)+sizeof(struct trllc);

        if (!(skb = dev_alloc_skb(skb_size))) {
                DPRINTK("out of memory. frame dropped.\n");
                ti->tr_stats.rx_dropped++;
                SET_PAGE(ti->asb_page);
                writeb(DATA_LOST, ti->asb + offsetof(struct asb_rec, ret_code));
                writeb(RESP_IN_ASB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);
                return;
        }
        /*BMS again, if she comes in with few but leaves with many */
        skb_reserve(skb, sizeof(struct trh_hdr) - lan_hdr_len);
        skb_put(skb, length);
        skb->dev = dev;
        data = skb->data;
        rbuffer_len = ntohs(readw(rbuf + offsetof(struct rec_buf, buf_len)));
        rbufdata = rbuf + offsetof(struct rec_buf, data);

        if (IPv4_p) {
                /* Copy the headers without checksumming */
                memcpy_fromio(data, rbufdata, hdr_len);

                /* Watch for padded packets and bogons */
                iph= (struct iphdr *)(data+ lan_hdr_len + sizeof(struct trllc));
                ip_len = ntohs(iph->tot_len) - sizeof(struct iphdr);
                length -= hdr_len;
                if ((ip_len <= length) && (ip_len > 7))
                        length = ip_len;
                data += hdr_len;
                rbuffer_len -= hdr_len;
                rbufdata += hdr_len;
        }
        /* Copy the payload... */
#define BUFFER_POINTER_OFST     2
#define BUFFER_LENGTH_OFST      6
        for (;;) {
                if (ibmtr_debug_trace&TRC_INITV && length < rbuffer_len)
                        DPRINTK("CURIOUS, length=%d < rbuffer_len=%d\n",
                                                length,rbuffer_len);
                if (IPv4_p)
                        chksum=csum_partial_copy_nocheck((void*)rbufdata,
                            data,length<rbuffer_len?length:rbuffer_len,chksum);
                else
                        memcpy_fromio(data, rbufdata, rbuffer_len);
                rbuffer = ntohs(readw(rbuf+BUFFER_POINTER_OFST)) ;
                if (!rbuffer)
                        break;
                rbuffer -= 2;
                length -= rbuffer_len;
                data += rbuffer_len;
                rbuf = map_address(ti, rbuffer, &rbuffer_page);
                SET_PAGE(rbuffer_page);
                rbuffer_len = ntohs(readw(rbuf + BUFFER_LENGTH_OFST));
                rbufdata = rbuf + offsetof(struct rec_buf, data);
        }

        SET_PAGE(ti->asb_page);
        writeb(0, ti->asb + offsetof(struct asb_rec, ret_code));

        writeb(RESP_IN_ASB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);

        ti->tr_stats.rx_bytes += skb->len;
        ti->tr_stats.rx_packets++;

        skb->protocol = tr_type_trans(skb, dev);
        if (IPv4_p) {
                skb->csum = chksum;
                skb->ip_summed = 1;
        }
        netif_rx(skb);
        dev->last_rx = jiffies;
}                               /*tr_rx */

/*****************************************************************************/

void ibmtr_reset_timer(struct timer_list *tmr, struct net_device *dev)
{
        tmr->expires = jiffies + TR_RETRY_INTERVAL;
        tmr->data = (unsigned long) dev;
        tmr->function = tok_rerun;
        init_timer(tmr);
        add_timer(tmr);
}

/*****************************************************************************/

void tok_rerun(unsigned long dev_addr){

        struct net_device *dev = (struct net_device *)dev_addr;
        struct tok_info *ti = (struct tok_info *) dev->priv;

        if ( ti->open_action == RESTART){
                ti->do_tok_int = FIRST_INT;
                outb(0, dev->base_addr + ADAPTRESETREL);
#ifdef ENABLE_PAGING
                if (ti->page_mask)
                        writeb(SRPR_ENABLE_PAGING,
                                ti->mmio + ACA_OFFSET + ACA_RW + SRPR_EVEN);
#endif

                writeb(INT_ENABLE, ti->mmio + ACA_OFFSET + ACA_SET + ISRP_EVEN);
        } else
                tok_open_adapter(dev_addr);
}

/*****************************************************************************/

void ibmtr_readlog(struct net_device *dev)
{
        struct tok_info *ti;

        ti = (struct tok_info *) dev->priv;

        ti->readlog_pending = 0;
        SET_PAGE(ti->srb_page);
        writeb(DIR_READ_LOG, ti->srb);
        writeb(INT_ENABLE, ti->mmio + ACA_OFFSET + ACA_SET + ISRP_EVEN);
        writeb(CMD_IN_SRB, ti->mmio + ACA_OFFSET + ACA_SET + ISRA_ODD);

        netif_stop_queue(dev);

}

/*****************************************************************************/

/* tok_get_stats():  Basically a scaffold routine which will return
   the address of the tr_statistics structure associated with
   this device -- the tr.... structure is an ethnet look-alike
   so at least for this iteration may suffice.   */

static struct net_device_stats *tok_get_stats(struct net_device *dev)
{

        struct tok_info *toki;
        toki = (struct tok_info *) dev->priv;
        return (struct net_device_stats *) &toki->tr_stats;
}

/*****************************************************************************/

int ibmtr_change_mtu(struct net_device *dev, int mtu)
{
        struct tok_info *ti = (struct tok_info *) dev->priv;

        if (ti->ring_speed == 16 && mtu > ti->maxmtu16)
                return -EINVAL;
        if (ti->ring_speed == 4 && mtu > ti->maxmtu4)
                return -EINVAL;
        dev->mtu = mtu;
        return 0;
}

/*****************************************************************************/
#ifdef MODULE

/* 3COM 3C619C supports 8 interrupts, 32 I/O ports */
static struct net_device *dev_ibmtr[IBMTR_MAX_ADAPTERS];
static int io[IBMTR_MAX_ADAPTERS] = { 0xa20, 0xa24 };
static int irq[IBMTR_MAX_ADAPTERS];
static int mem[IBMTR_MAX_ADAPTERS];

MODULE_LICENSE("GPL");

module_param_array(io, int, NULL, 0);
module_param_array(irq, int, NULL, 0);
module_param_array(mem, int, NULL, 0);

static int __init ibmtr_init(void)
{
        int i;
        int count=0;

        find_turbo_adapters(io);

        for (i = 0; io[i] && (i < IBMTR_MAX_ADAPTERS); i++) {
                struct net_device *dev;
                irq[i] = 0;
                mem[i] = 0;
                dev = alloc_trdev(sizeof(struct tok_info));
                if (dev == NULL) { 
                        if (i == 0)
                                return -ENOMEM;
                        break;
                }
                dev->base_addr = io[i];
                dev->irq = irq[i];
                dev->mem_start = mem[i];

                if (ibmtr_probe_card(dev)) {
                        free_netdev(dev);
                        continue;
                }
                dev_ibmtr[i] = dev;
                count++;
        }
        if (count) return 0;
        printk("ibmtr: register_netdev() returned non-zero.\n");
        return -EIO;
}
module_init(ibmtr_init);

static void __exit ibmtr_cleanup(void)
{
        int i;

        for (i = 0; i < IBMTR_MAX_ADAPTERS; i++){
                if (!dev_ibmtr[i])
                        continue;
                unregister_netdev(dev_ibmtr[i]);
                ibmtr_cleanup_card(dev_ibmtr[i]);
                free_netdev(dev_ibmtr[i]);
        }
}
module_exit(ibmtr_cleanup);
#endif