/*
 * ni6510 (am7990 'lance' chip) driver for Linux-net-3
 * BETAcode v0.70 (96/04/07) for 1.3.66 (or later)
 * copyrights (c) 1994,1995,1996 by M.Hipp
 * 
 * This driver can handle the old ni6510 board and the newer ni6510 
 * EtherBlaster. (probably it also works with every full NE2100 
 * compatible card)
 *
 * To compile as module, type:
 *     gcc -O2 -fomit-frame-pointer -m486 -D__KERNEL__ -DMODULE -c ni65.c
 * driver probes: io: 0x360,0x300,0x320,0x340 / dma: 3,5,6,7
 *
 * This is an extension to the Linux operating system, and is covered by the
 * same Gnu Public License that covers the Linux-kernel.
 *
 * comments/bugs/suggestions can be sent to:
 *   Michael Hipp
 *   email: Michael.Hipp@student.uni-tuebingen.de
 *
 * sources:
 *   some things are from the 'ni6510-packet-driver for dos by Russ Nelson'
 *   and from the original drivers by D.Becker
 *
 * known problems:
 *   on some PCI boards (including my own) the card/board/ISA-bridge has
 *   problems with bus master DMA. This results in lotsa overruns.
 *   It may help to '#define RCV_PARANOIA_CHECK' or try to #undef
 *   the XMT and RCV_VIA_SKB option .. this reduces driver performance.
 *   Or just play with your BIOS options to optimize ISA-DMA access.
 *   Maybe you also wanna play with the LOW_PERFORAMCE and MID_PERFORMANCE
 *   defines -> please report me your experience then
 *
 * credits:
 *   thanx to Jason Sullivan for sending me a ni6510 card!
 *
 * simple performance test: (486DX-33/Ni6510-EB receives from 486DX4-100/Ni6510-EB)
 *    average: FTP -> 8384421 bytes received in 8.5 seconds
 *           (no RCV_VIA_SKB,no XMT_VIA_SKB,PARANOIA_CHECK,4 XMIT BUFS, 8 RCV_BUFFS)
 *    peak: FTP -> 8384421 bytes received in 7.5 seconds 
 *           (RCV_VIA_SKB,XMT_VIA_SKB,no PARANOIA_CHECK,1(!) XMIT BUF, 16 RCV BUFFS)
 */

/*
 * 96.April.13: enhanced error handling .. more tests (MH)
 * 96.April.5/6: a lot of performance tests .. got it stable now (hopefully) (MH)
 * 96.April.1: (no joke ;) .. added EtherBlaster and Module support (MH)
 * 96.Feb.19: fixed a few bugs .. cleanups .. tested for 1.3.66 (MH)
 *            hopefully no more 16MB limit
 *
 * 95.Nov.18: multicast tweaked (AC).
 *
 * 94.Aug.22: changes in xmit_intr (ack more than one xmitted-packet), ni65_send_packet (p->lock) (MH)
 *
 * 94,July.16: fixed bugs in recv_skb and skb-alloc stuff  (MH)
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/malloc.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <asm/bitops.h>
#include <asm/io.h>
#include <asm/dma.h>

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>

#include <linux/version.h>
#include <linux/module.h>

#include "ni65.h"

/*
 * the current setting allows an acceptable performance
 * for 'RCV_PARANOIA_CHECK' read the 'known problems' part in 
 * the header of this file
 * 'invert' the defines for max. performance. This may cause DMA problems
 * on some boards (e.g on my ASUS SP3G)
 */
#define XMT_VIA_SKB
#define RCV_VIA_SKB
#define RCV_PARANOIA_CHECK

#define MID_PERFORMANCE

#if   defined( LOW_PERFORMANCE )
 static int isa0=7,isa1=7,csr80=0x0c10;
#elif defined( MID_PERFORMANCE )
 static int isa0=5,isa1=5,csr80=0x2810;
#else	/* high performance */
 static int isa0=4,isa1=4,csr80=0x0017;
#endif

/*
 * a few card/vendor specific defines
 */
#define NI65_ID0    0x00
#define NI65_ID1    0x55
#define NI65_EB_ID0 0x52
#define NI65_EB_ID1 0x44
#define NE2100_ID0  0x57
#define NE2100_ID1  0x57

#define PORT p->cmdr_addr

/*
 * buffer configuration
 */
#if 1
#define RMDNUM 16
#define RMDNUMMASK 0x80000000 
#else
#define RMDNUM 8
#define RMDNUMMASK 0x60000000 /* log2(RMDNUM)<<29 */
#endif

#if 1
#define TMDNUM 1
#define TMDNUMMASK 0x00000000 /* log2(TMDNUM)<<29 */
#else
#define TMDNUM 2
#define TMDNUMMASK 0x20000000 /* log2(TMDNUM)<<29 */
#endif

/* slightly oversized */
#define R_BUF_SIZE 1544
#define T_BUF_SIZE 1544

/*
 * lance register defines
 */
#define L_DATAREG 0x00
#define L_ADDRREG 0x02
#define L_RESET   0x04
#define L_CONFIG  0x05
#define L_BUSIF   0x06

/* 
 * to access the lance/am7990-regs, you have to write
 * reg-number into L_ADDRREG, then you can access it using L_DATAREG
 */
#define CSR0  0x00
#define CSR1  0x01
#define CSR2  0x02
#define CSR3  0x03

#define INIT_RING_BEFORE_START	0x1
#define FULL_RESET_ON_ERROR	0x2

#if 0
#define writereg(val,reg) {outw(reg,PORT+L_ADDRREG);inw(PORT+L_ADDRREG); \
                           outw(val,PORT+L_DATAREG);inw(PORT+L_DATAREG);}
#define readreg(reg) (outw(reg,PORT+L_ADDRREG),inw(PORT+L_ADDRREG),\
                       inw(PORT+L_DATAREG))
#if 0
#define writedatareg(val) {outw(val,PORT+L_DATAREG);inw(PORT+L_DATAREG);}
#else
#define writedatareg(val) {  writereg(val,CSR0); }
#endif
#else
#define writereg(val,reg) {outw(reg,PORT+L_ADDRREG);outw(val,PORT+L_DATAREG);}
#define readreg(reg) (outw(reg,PORT+L_ADDRREG),inw(PORT+L_DATAREG))
#define writedatareg(val) { writereg(val,CSR0); }
#endif

static unsigned char ni_vendor[] = { 0x02,0x07,0x01 };

static struct card {
	unsigned char id0,id1;
	short id_offset;
	short total_size;
	short cmd_offset;
	short addr_offset;
	unsigned char *vendor_id;
	char *cardname;
	unsigned char config;
} cards[] = {
	{ NI65_ID0,NI65_ID1,0x0e,0x10,0x0,0x8,ni_vendor,"ni6510", 0x1 } ,
	{ NI65_EB_ID0,NI65_EB_ID1,0x0e,0x18,0x10,0x0,ni_vendor,"ni6510 EtherBlaster", 0x2 } ,
	{ NE2100_ID0,NE2100_ID1,0x0e,0x18,0x10,0x0,NULL,"generic NE2100", 0x0 }
};
#define NUM_CARDS 3

struct priv 
{
  struct rmd rmdhead[RMDNUM];
  struct tmd tmdhead[TMDNUM];
  struct init_block ib; 
  int rmdnum;
  int tmdnum,tmdlast;
#ifdef RCV_VIA_SKB
  struct sk_buff *recv_skb[RMDNUM];
#else
  void *recvbounce[RMDNUM];
#endif
#ifdef XMT_VIA_SKB
  struct sk_buff *tmd_skb[TMDNUM];
#endif
  void *tmdbounce[TMDNUM];
  int tmdbouncenum;
  int lock,xmit_queued;
  struct enet_statistics stats;
  void *self;
  int cmdr_addr;
  int cardno;
  int features;
}; 

static int  ni65_probe1(struct device *dev,int);
static void ni65_interrupt(int irq, void * dev_id, struct pt_regs *regs);
static void ni65_recv_intr(struct device *dev,int);
static void ni65_xmit_intr(struct device *dev,int);
static int  ni65_open(struct device *dev);
static int  ni65_lance_reinit(struct device *dev);
static void ni65_init_lance(struct priv *p,unsigned char*,int,int);
static int  ni65_send_packet(struct sk_buff *skb, struct device *dev);
static int  ni65_close(struct device *dev);
static int  ni65_alloc_buffer(struct device *dev);
static void ni65_free_buffer(struct priv *p);
static struct enet_statistics *ni65_get_stats(struct device *);
static void set_multicast_list(struct device *dev);

static int irqtab[] = { 9,12,15,5 }; /* irq config-translate */
static int dmatab[] = { 0,3,5,6,7 }; /* dma config-translate and autodetect */

static int debuglevel = 1;

/*
 * set 'performance' registers .. we must STOP lance for that
 */
static void ni65_set_performance(struct priv *p)
{
  writereg(CSR0_STOP | CSR0_CLRALL,CSR0); /* STOP */

  if(!test_bit(1,&cards[p->cardno].config))
    return;
 
  outw(80,PORT+L_ADDRREG);
  if(inw(PORT+L_ADDRREG) != 80)
    return;
 
  writereg( (csr80 & 0x3fff) ,80); /* FIFO watermarks */
  outw(0,PORT+L_ADDRREG);
  outw((short)isa0,PORT+L_BUSIF); /* write ISA 0: DMA_R : isa0 * 50ns */
  outw(1,PORT+L_ADDRREG);
  outw((short)isa1,PORT+L_BUSIF); /* write ISA 1: DMA_W : isa1 * 50ns  */

  outw(CSR0,PORT+L_ADDRREG);	/* switch back to CSR0 */
}

/*
 * open interface (up)
 */
static int ni65_open(struct device *dev)
{
  struct priv *p = (struct priv *) dev->priv;
  int irqval = request_irq(dev->irq, &ni65_interrupt,0,
                        cards[p->cardno].cardname,NULL);
  if (irqval) {
    printk ("%s: unable to get IRQ %d (irqval=%d).\n", 
              dev->name,dev->irq, irqval);
    return -EAGAIN;
  }
  irq2dev_map[dev->irq] = dev;

  if(ni65_lance_reinit(dev))
  {
    dev->tbusy     = 0;
    dev->interrupt = 0;
    dev->start     = 1;
    MOD_INC_USE_COUNT;
    return 0;
  }
  else
  {
    irq2dev_map[dev->irq] = NULL;
    free_irq(dev->irq,NULL);
    dev->start = 0;
    return -EAGAIN;
  }
}

/*
 * close interface (down)
 */
static int ni65_close(struct device *dev)
{
  struct priv *p = (struct priv *) dev->priv;

  outw(inw(PORT+L_RESET),PORT+L_RESET); /* that's the hard way */

#ifdef XMT_VIA_SKB
  {
    int i;
    for(i=0;i<TMDNUM;i++)
    {
      if(p->tmd_skb[i]) {
        dev_kfree_skb(p->tmd_skb[i],FREE_WRITE);
        p->tmd_skb[i] = NULL;
      }
    }
  }
#endif
  irq2dev_map[dev->irq] = NULL;
  free_irq(dev->irq,NULL);
  dev->tbusy = 1;
  dev->start = 0;
  MOD_DEC_USE_COUNT;
  return 0; 
}

/* 
 * Probe The Card (not the lance-chip) 
 */ 
#ifdef MODULE
static
#endif
int ni65_probe(struct device *dev)
{
  int *port;
  static int ports[] = {0x360,0x300,0x320,0x340, 0};

  if (dev->base_addr > 0x1ff)          /* Check a single specified location. */
     return ni65_probe1(dev, dev->base_addr);
  else if (dev->base_addr > 0)         /* Don't probe at all. */
     return -ENXIO;

  for (port = ports; *port; port++) 
  {
    if (ni65_probe1(dev, *port) == 0)
       return 0;
  }

  return -ENODEV;
}

/*
 * this is the real card probe .. 
 */
static int ni65_probe1(struct device *dev,int ioaddr)
{
  int i,j;
  struct priv *p; 

  for(i=0;i<NUM_CARDS;i++) {
    if(check_region(ioaddr, cards[i].total_size))
      continue;
    if(cards[i].id_offset >= 0) {
      if(inb(ioaddr+cards[i].id_offset+0) != cards[i].id0 ||
         inb(ioaddr+cards[i].id_offset+1) != cards[i].id1) {
         continue;
      }
    }
    if(cards[i].vendor_id) {
      for(j=0;j<3;j++)
        if(inb(ioaddr+cards[i].addr_offset+j) != cards[i].vendor_id[j])
          continue;
    }
    break;
  }
  if(i == NUM_CARDS)
    return -ENODEV;

  for(j=0;j<6;j++)
    dev->dev_addr[j] = inb(ioaddr+cards[i].addr_offset+j);

  if( (j=ni65_alloc_buffer(dev)) < 0)
    return j;
  p = (struct priv *) dev->priv;
  p->cmdr_addr = ioaddr + cards[i].cmd_offset;
  p->cardno = i;

  printk("%s: %s found at %#3x, ", dev->name, cards[p->cardno].cardname , ioaddr);

  outw(inw(PORT+L_RESET),PORT+L_RESET); /* first: reset the card */
  if( (j=readreg(CSR0)) != 0x4) {
     printk(KERN_ERR "can't RESET card: %04x\n",j);
     ni65_free_buffer(p);
     return -EAGAIN;
  }

  outw(88,PORT+L_ADDRREG);
  if(inw(PORT+L_ADDRREG) == 88) {
    unsigned long v;
    v = inw(PORT+L_DATAREG);
    v <<= 16;
    outw(89,PORT+L_ADDRREG);
    v |= inw(PORT+L_DATAREG);
    printk("Version %#08lx, ",v);
    p->features = INIT_RING_BEFORE_START;
  }
  else {
    printk("ancient LANCE, ");
    p->features = 0x0;
  }

  if(test_bit(0,&cards[i].config)) {
    dev->irq = irqtab[(inw(ioaddr+L_CONFIG)>>2)&3];
    dev->dma = dmatab[inw(ioaddr+L_CONFIG)&3];
    printk("IRQ %d (from card), DMA %d (from card).\n",dev->irq,dev->dma);
  }
  else {
    if(dev->dma == 0) {
		/* 'stuck test' from lance.c */
      int dma_channels = ((inb(DMA1_STAT_REG) >> 4) & 0x0f) | (inb(DMA2_STAT_REG) & 0xf0);
      for(i=1;i<5;i++) {
        int dma = dmatab[i];
        if(test_bit(dma,&dma_channels) || request_dma(dma,"ni6510"))
          continue;
        disable_dma(dma);
        set_dma_mode(dma,DMA_MODE_CASCADE);
        enable_dma(dma);
        ni65_init_lance(p,dev->dev_addr,0,0); /* trigger memory access */
        disable_dma(dma);
        free_dma(dma);
        if(readreg(CSR0) & CSR0_IDON)
          break;
      }
      if(i == 5) {
        printk("Can't detect DMA channel!\n");
        ni65_free_buffer(p);
        return -EAGAIN;
      }
      dev->dma = dmatab[i];
      printk("DMA %d (autodetected), ",dev->dma);
    }
    else
      printk("DMA %d (assigned), ",dev->dma);

    if(dev->irq < 2)
    {
      ni65_init_lance(p,dev->dev_addr,0,0);
      autoirq_setup(0);
      writereg(CSR0_INIT|CSR0_INEA,CSR0); /* trigger interrupt */

      if(!(dev->irq = autoirq_report(2)))
      {
        printk("Failed to detect IRQ line!\n");
        ni65_free_buffer(p);
        return -EAGAIN;
      }
      printk("IRQ %d (autodetected).\n",dev->irq);
    }
    else
      printk("IRQ %d (assigned).\n",dev->irq);
  }

  if(request_dma(dev->dma, cards[p->cardno].cardname ) != 0)
  {
    printk("%s: Can't request dma-channel %d\n",dev->name,(int) dev->dma);
    ni65_free_buffer(p);
    return -EAGAIN;
  }

  /* 
   * Grab the region so we can find another board. 
   */
  request_region(ioaddr,cards[p->cardno].total_size,cards[p->cardno].cardname);

  dev->base_addr = ioaddr;

  dev->open               = ni65_open;
  dev->stop               = ni65_close;
  dev->hard_start_xmit    = ni65_send_packet;
  dev->get_stats          = ni65_get_stats;
  dev->set_multicast_list = set_multicast_list;

  ether_setup(dev);

  dev->interrupt      = 0;
  dev->tbusy          = 0;
  dev->start          = 0;

  return 0; /* everything is OK */
}

/*
 * set lance register and trigger init 
 */
static void ni65_init_lance(struct priv *p,unsigned char *daddr,int filter,int mode) 
{
  int i;

  writereg(CSR0_CLRALL|CSR0_STOP,CSR0);

  for(i=0;i<6;i++)
    p->ib.eaddr[i] = daddr[i];

  for(i=0;i<8;i++)
    p->ib.filter[i] = filter;
  p->ib.mode = mode;

  p->ib.trp = (unsigned long) p->tmdhead | TMDNUMMASK;
  p->ib.rrp = (unsigned long) p->rmdhead | RMDNUMMASK;
  writereg(0,CSR3);  /* busmaster/no word-swap */
  writereg((unsigned short) (((unsigned long) &(p->ib)) & 0xffff),CSR1);
  writereg((unsigned short) (((unsigned long) &(p->ib))>>16),CSR2);

  writereg(CSR0_INIT,CSR0); /* this changes L_ADDRREG to CSR0 */

  for(i=0;i<32;i++)
  {
    udelay(4000);
    if(inw(PORT+L_DATAREG) & (CSR0_IDON | CSR0_MERR) )
      break; /* init ok ? */
  }
}

/*
 * allocate memory area and check the 16MB border
 */
static void *ni65_alloc_mem(struct device *dev,char *what,int size,int type)
{
  struct sk_buff *skb=NULL;
  unsigned char *ptr;
  void *ret;

  if(type) {
    ret = skb = alloc_skb(2+16+size,GFP_KERNEL|GFP_DMA);
    if(!skb) {
      printk("%s: unable to allocate %s memory.\n",dev->name,what);
      return NULL;
    }
    skb->dev = dev;
    skb_reserve(skb,2+16);
    skb_put(skb,R_BUF_SIZE);   /* grab the whole space .. (not necessary) */
    ptr = skb->data;
  }
  else {
    ret = ptr = kmalloc(T_BUF_SIZE,GFP_KERNEL | GFP_DMA);
    if(!ret) {
      printk("%s: unable to allocate %s memory.\n",dev->name,what);
      return NULL;
    }
  }
  if( (unsigned long) (ptr+size) > 0x1000000) {
    printk("%s: unable to allocate %s memory in lower 16MB!\n",dev->name,what);
    if(type)
      kfree_skb(skb,FREE_WRITE);
    else
      kfree(ptr);
    return NULL;
  }
  return ret;
}

/*
 * allocate all memory structures .. send/recv buffers etc ...
 */
static int ni65_alloc_buffer(struct device *dev)
{
  unsigned char *ptr;
  struct priv *p;
  int i;
 
  /* 
   * we need 8-aligned memory ..
   */
  ptr = ni65_alloc_mem(dev,"BUFFER",sizeof(struct priv)+8,0);
  if(!ptr)
    return -ENOMEM;

  p = dev->priv = (struct priv *) (((unsigned long) ptr + 7) & ~0x7);
  memset((char *) dev->priv,0,sizeof(struct priv));
  p->self = ptr;

  for(i=0;i<TMDNUM;i++)
  {
#ifdef XMT_VIA_SKB
    p->tmd_skb[i] = NULL;
#endif
    p->tmdbounce[i] = ni65_alloc_mem(dev,"XMIT",T_BUF_SIZE,0);
    if(!p->tmdbounce[i]) {
      ni65_free_buffer(p);
      return -ENOMEM;
    }
  }

  for(i=0;i<RMDNUM;i++)
  {
#ifdef RCV_VIA_SKB
    p->recv_skb[i] = ni65_alloc_mem(dev,"RECV",R_BUF_SIZE,1);
    if(!p->recv_skb[i]) {
      ni65_free_buffer(p);
      return -ENOMEM;
    }
#else
    p->recvbounce[i] = ni65_alloc_mem(dev,"RECV",R_BUF_SIZE,0);
    if(!p->recvbounce[i]) {
      ni65_free_buffer(p);
      return -ENOMEM;
    }
#endif
  }

  return 0; /* everything is OK */
}

/*
 * free buffers and private struct 
 */
static void ni65_free_buffer(struct priv *p)
{
  int i;

  if(!p)
    return;

  for(i=0;i<TMDNUM;i++) {
    if(p->tmdbounce[i])
      kfree(p->tmdbounce[i]);
#ifdef XMT_VIA_SKB
    if(p->tmd_skb[i])
      dev_kfree_skb(p->tmd_skb[i],FREE_WRITE);
#endif
  }

  for(i=0;i<RMDNUM;i++)
  {
#ifdef RCV_VIA_SKB
    if(p->recv_skb[i])
      dev_kfree_skb(p->recv_skb[i],FREE_WRITE);
#else
    if(p->recvbounce[i])
      kfree(p->recvbounce[i]);
#endif
  }
  if(p->self)
    kfree(p->self);
}


/*
 * stop and (re)start lance .. e.g after an error
 */
static void ni65_stop_start(struct device *dev,struct priv *p)
{
  int csr0 = CSR0_INEA;

  writedatareg(CSR0_STOP);

  if(debuglevel > 1)
    printk("ni65_stop_start\n");

  if(p->features & INIT_RING_BEFORE_START) {
    int i;
#ifdef XMT_VIA_SKB
    struct sk_buff *skb_save[TMDNUM];
#endif
    unsigned long buffer[TMDNUM];
    short blen[TMDNUM];

    if(p->xmit_queued) {
      while(1) {
        if((p->tmdhead[p->tmdlast].u.s.status & XMIT_OWN))
          break;
        p->tmdlast = (p->tmdlast + 1) & (TMDNUM-1);
        if(p->tmdlast == p->tmdnum)
          break;
      }
    }
    
    for(i=0;i<TMDNUM;i++) {
      struct tmd *tmdp = p->tmdhead + i;
#ifdef XMT_VIA_SKB
      skb_save[i] = p->tmd_skb[i];
#endif
      buffer[i] = tmdp->u.buffer;
      blen[i] = tmdp->blen;
      tmdp->u.s.status = 0x0;
    }

    for(i=0;i<RMDNUM;i++) {
      struct rmd *rmdp = p->rmdhead + i;
      rmdp->u.s.status = RCV_OWN;
    }
    p->tmdnum = p->xmit_queued = 0;
    writedatareg(CSR0_STRT | csr0);

    for(i=0;i<TMDNUM;i++) {
      int num = (i + p->tmdlast) & (TMDNUM-1);
      p->tmdhead[i].u.buffer = buffer[num]; /* status is part of buffer field */
      p->tmdhead[i].blen = blen[num];
      if(p->tmdhead[i].u.s.status & XMIT_OWN) {
	 p->tmdnum = (p->tmdnum + 1) & (TMDNUM-1);
         p->xmit_queued = 1;
	 writedatareg(CSR0_TDMD | CSR0_INEA | csr0);
      }
#ifdef XMT_VIA_SKB
      p->tmd_skb[i] = skb_save[num];
#endif
    }
    p->rmdnum = p->tmdlast = 0;
    if(!p->lock)
      dev->tbusy = (p->tmdnum || !p->xmit_queued) ? 0 : 1;
    dev->trans_start = jiffies;
  } 
  else
    writedatareg(CSR0_STRT | csr0);
}

/* 
 * init lance (write init-values .. init-buffers) (open-helper)
 */
static int ni65_lance_reinit(struct device *dev)
{
   int i;
   struct priv *p = (struct priv *) dev->priv;

   p->lock = 0;
   p->xmit_queued = 0;

   disable_dma(dev->dma); /* I've never worked with dma, but we do it like the packetdriver */
   set_dma_mode(dev->dma,DMA_MODE_CASCADE);
   enable_dma(dev->dma); 

   outw(inw(PORT+L_RESET),PORT+L_RESET); /* first: reset the card */
   if( (i=readreg(CSR0) ) != 0x4)
   {
     printk(KERN_ERR "%s: can't RESET %s card: %04x\n",dev->name,
              cards[p->cardno].cardname,(int) i);
     disable_dma(dev->dma);
     return 0;
   }

   p->rmdnum = p->tmdnum = p->tmdlast = p->tmdbouncenum = 0;
   for(i=0;i<TMDNUM;i++)
   {
     struct tmd *tmdp = p->tmdhead + i;
#ifdef XMT_VIA_SKB
     if(p->tmd_skb[i]) {
       dev_kfree_skb(p->tmd_skb[i],FREE_WRITE);
       p->tmd_skb[i] = NULL;
     }
#endif
     tmdp->u.buffer = 0x0;
     tmdp->u.s.status = XMIT_START | XMIT_END;
     tmdp->blen = tmdp->status2 = 0;
   }

   for(i=0;i<RMDNUM;i++)
   {
     struct rmd *rmdp = p->rmdhead + i;
#ifdef RCV_VIA_SKB
     rmdp->u.buffer = (unsigned long) p->recv_skb[i]->data;
#else
     rmdp->u.buffer = (unsigned long) p->recvbounce[i];
#endif
     rmdp->blen = -(R_BUF_SIZE-8);
     rmdp->mlen = 0;
     rmdp->u.s.status = RCV_OWN;
   }
   
   if(dev->flags & IFF_PROMISC)
     ni65_init_lance(p,dev->dev_addr,0x00,M_PROM);
   else if(dev->mc_count || dev->flags & IFF_ALLMULTI)
     ni65_init_lance(p,dev->dev_addr,0xff,0x0);
   else 
     ni65_init_lance(p,dev->dev_addr,0x00,0x00);

  /*
   * ni65_set_lance_mem() sets L_ADDRREG to CSR0
   * NOW, WE WILL NEVER CHANGE THE L_ADDRREG, CSR0 IS ALWAYS SELECTED 
   */

   if(inw(PORT+L_DATAREG) & CSR0_IDON)  {
     ni65_set_performance(p);
           /* init OK: start lance , enable interrupts */
     writedatareg(CSR0_CLRALL | CSR0_INEA | CSR0_STRT);
     return 1; /* ->OK */
   }
   printk(KERN_ERR "%s: can't init lance, status: %04x\n",dev->name,(int) inw(PORT+L_DATAREG));
   disable_dma(dev->dma);
   return 0; /* ->Error */
}
 
/* 
 * interrupt handler  
 */
static void ni65_interrupt(int irq, void * dev_id, struct pt_regs * regs)
{
  int csr0;
  struct device *dev = (struct device *) irq2dev_map[irq];
  struct priv *p;
  int bcnt = 32;

  if (dev == NULL) {
    printk (KERN_ERR "ni65_interrupt(): irq %d for unknown device.\n", irq);
    return;
  }

  if(set_bit(0,(int *) &dev->interrupt)) {
    printk("ni65: oops .. interrupt while proceeding interrupt\n");
    return;
  }
  p = (struct priv *) dev->priv;

  while(--bcnt) {
    csr0 = inw(PORT+L_DATAREG);

#if 0
    writedatareg( (csr0 & CSR0_CLRALL) ); /* ack interrupts, disable int. */
#else
    writedatareg( (csr0 & CSR0_CLRALL) | CSR0_INEA ); /* ack interrupts, interrupts enabled */
#endif

    if(!(csr0 & (CSR0_ERR | CSR0_RINT | CSR0_TINT)))
      break;

    if(csr0 & CSR0_RINT) /* RECV-int? */
      ni65_recv_intr(dev,csr0);
    if(csr0 & CSR0_TINT) /* XMIT-int? */
      ni65_xmit_intr(dev,csr0);

    if(csr0 & CSR0_ERR)
    {
      struct priv *p = (struct priv *) dev->priv;
      if (debuglevel > 1)
	printk("%s: general error: %04x.\n",dev->name,csr0);
      if(csr0 & CSR0_BABL)
        p->stats.tx_errors++;
      if(csr0 & CSR0_MISS) {
        int i;
        for(i=0;i<RMDNUM;i++)
          printk("%02x ",p->rmdhead[i].u.s.status);
        printk("\n");
        p->stats.rx_errors++;
      }
      if(csr0 & CSR0_MERR) {
	if (debuglevel > 1)
	  printk("%s: Ooops .. memory error: %04x.\n",dev->name,csr0);
        ni65_stop_start(dev,p);
      }
    }
  }

#ifdef RCV_PARANOIA_CHECK
{
 int j;
 for(j=0;j<RMDNUM;j++)
 {
  struct priv *p = (struct priv *) dev->priv;
  int i,k,num1,num2;
  for(i=RMDNUM-1;i>0;i--) {
     num2 = (p->rmdnum + i) & (RMDNUM-1);
     if(!(p->rmdhead[num2].u.s.status & RCV_OWN))
        break;
  }

  if(i) {
    for(k=0;k<RMDNUM;k++) {
      num1 = (p->rmdnum + k) & (RMDNUM-1);
      if(!(p->rmdhead[num1].u.s.status & RCV_OWN))
        break;
    }
    if(!k)
      break;

    if(debuglevel > 0)
    {
      char buf[256],*buf1;
      int k;
      buf1 = buf;
      for(k=0;k<RMDNUM;k++) {
        sprintf(buf1,"%02x ",(p->rmdhead[k].u.s.status)); /* & RCV_OWN) ); */
        buf1 += 3;
      }
      *buf1 = 0;
      printk(KERN_ERR "%s: Ooops, receive ring corrupted %2d %2d | %s\n",dev->name,p->rmdnum,i,buf);
    }

    p->rmdnum = num1;
    ni65_recv_intr(dev,csr0);
    if((p->rmdhead[num2].u.s.status & RCV_OWN))
      break;	/* ok, we are 'in sync' again */
  }
  else
    break;
 }
}
#endif

  if(csr0 & (CSR0_RXON | CSR0_TXON) != (CSR0_RXON | CSR0_TXON) ) {
    printk("%s: RX or TX was offline -> restart\n",dev->name);
    ni65_stop_start(dev,p);
  }
  else
    writedatareg(CSR0_INEA);

  dev->interrupt = 0;

  return;
}

/*
 * We have received an Xmit-Interrupt ..
 * send a new packet if necessary
 */
static void ni65_xmit_intr(struct device *dev,int csr0)
{
  struct priv *p = (struct priv *) dev->priv;

  while(p->xmit_queued)
  {
    struct tmd *tmdp = p->tmdhead + p->tmdlast;
    int tmdstat = tmdp->u.s.status;

    if(tmdstat & XMIT_OWN)
      break;

    if(tmdstat & XMIT_ERR)
    {
#if 0
      if(tmdp->status2 & XMIT_TDRMASK && debuglevel > 3)
        printk(KERN_ERR "%s: tdr-problems (e.g. no resistor)\n",dev->name);
#endif
     /* checking some errors */
      if(tmdp->status2 & XMIT_RTRY)
        p->stats.tx_aborted_errors++;
      if(tmdp->status2 & XMIT_LCAR)
        p->stats.tx_carrier_errors++;
      if(tmdp->status2 & (XMIT_BUFF | XMIT_UFLO )) {
		/* this stops the xmitter */
        p->stats.tx_fifo_errors++;
        if(debuglevel > 0)
          printk(KERN_ERR "%s: Xmit FIFO/BUFF error\n",dev->name);
        if(p->features & INIT_RING_BEFORE_START) {
          tmdp->u.s.status = XMIT_OWN | XMIT_START | XMIT_END;	/* test: resend this frame */
          ni65_stop_start(dev,p);
          break;	/* no more Xmit processing .. */
        }
        else
         ni65_stop_start(dev,p);
      }
      if(debuglevel > 2)
        printk(KERN_ERR "%s: xmit-error: %04x %02x-%04x\n",dev->name,csr0,(int) tmdstat,(int) tmdp->status2);
      if(!(csr0 & CSR0_BABL)) /* don't count errors twice */
        p->stats.tx_errors++;
      tmdp->status2 = 0;
    }
    else
      p->stats.tx_packets++;

#ifdef XMT_VIA_SKB
    if(p->tmd_skb[p->tmdlast]) {
       dev_kfree_skb(p->tmd_skb[p->tmdlast],FREE_WRITE);
       p->tmd_skb[p->tmdlast] = NULL;
    }
#endif

    p->tmdlast = (p->tmdlast + 1) & (TMDNUM-1);
    if(p->tmdlast == p->tmdnum)
      p->xmit_queued = 0;
  }
  dev->tbusy = 0;
  mark_bh(NET_BH);
}

/*
 * We have received a packet
 */
static void ni65_recv_intr(struct device *dev,int csr0)
{
  struct rmd *rmdp; 
  int rmdstat,len;
  int cnt=0;
  struct priv *p = (struct priv *) dev->priv;

  rmdp = p->rmdhead + p->rmdnum;
  while(!( (rmdstat = rmdp->u.s.status) & RCV_OWN))
  {
    cnt++;
    if( (rmdstat & (RCV_START | RCV_END | RCV_ERR)) != (RCV_START | RCV_END) ) /* error or oversized? */ 
    {
      if(!(rmdstat & RCV_ERR)) {
        if(rmdstat & RCV_START)
        {
          p->stats.rx_length_errors++;
          printk(KERN_ERR "%s: recv, packet too long: %d\n",dev->name,rmdp->mlen & 0x0fff);
        }
      }
      else {
        if(debuglevel > 2)
          printk(KERN_ERR "%s: receive-error: %04x, lance-status: %04x/%04x\n",
                  dev->name,(int) rmdstat,csr0,(int) inw(PORT+L_DATAREG) );
        if(rmdstat & RCV_FRAM)
          p->stats.rx_frame_errors++;
        if(rmdstat & RCV_OFLO)
          p->stats.rx_over_errors++;
        if(rmdstat & RCV_CRC) 
          p->stats.rx_crc_errors++;
        if(rmdstat & RCV_BUF_ERR)
          p->stats.rx_fifo_errors++;
      }
      if(!(csr0 & CSR0_MISS)) /* don't count errors twice */
        p->stats.rx_errors++;
    }
    else if( (len = (rmdp->mlen & 0x0fff) - 4) >= 60)
    {
#ifdef RCV_VIA_SKB
      struct sk_buff *skb = alloc_skb(R_BUF_SIZE+2+16,GFP_ATOMIC);
      if (skb)
        skb_reserve(skb,16);
#else
      struct sk_buff *skb = dev_alloc_skb(len+2);
#endif
      if(skb)
      {
        skb_reserve(skb,2);
	skb->dev = dev;
#ifdef RCV_VIA_SKB
        if( (unsigned long) (skb->data + R_BUF_SIZE) > 0x1000000) {
          skb_put(skb,len);
          eth_copy_and_sum(skb, (unsigned char *)(p->recv_skb[p->rmdnum]->data),len,0);
        }
        else {
          struct sk_buff *skb1 = p->recv_skb[p->rmdnum];
          skb_put(skb,R_BUF_SIZE);
          p->recv_skb[p->rmdnum] = skb;
          rmdp->u.buffer = (unsigned long) skb->data;
          skb = skb1;
          skb_trim(skb,len);
        }
#else
        skb_put(skb,len);
        eth_copy_and_sum(skb, (unsigned char *) p->recvbounce[p->rmdnum],len,0);
#endif
        p->stats.rx_packets++;
        skb->protocol=eth_type_trans(skb,dev);
        netif_rx(skb);
      }
      else
      {
        printk(KERN_ERR "%s: can't alloc new sk_buff\n",dev->name);
        p->stats.rx_dropped++;
      }
    }
    else {
      printk(KERN_INFO "%s: received runt packet\n",dev->name);
      p->stats.rx_errors++;
    }
    rmdp->blen = -(R_BUF_SIZE-8);
    rmdp->mlen = 0;
    rmdp->u.s.status = RCV_OWN; /* change owner */
    p->rmdnum = (p->rmdnum + 1) & (RMDNUM-1);
    rmdp = p->rmdhead + p->rmdnum;
  }
}

/*
 * kick xmitter ..
 */
static int ni65_send_packet(struct sk_buff *skb, struct device *dev)
{
  struct priv *p = (struct priv *) dev->priv;

  if(dev->tbusy)
  {
    int tickssofar = jiffies - dev->trans_start;
    if (tickssofar < 50)
      return 1;

    printk(KERN_ERR "%s: xmitter timed out, try to restart!\n",dev->name);
#if 0
{
  int i;
  for(i=0;i<TMDNUM;i++)
    printk("%02x ",p->tmdhead[i].u.s.status);
  printk("\n");
}
#endif
    ni65_lance_reinit(dev);
    dev->tbusy=0;
    dev->trans_start = jiffies;
  }

  if(skb == NULL) {
    dev_tint(dev);
    return 0;
  }

  if (skb->len <= 0)
    return 0;

  if (set_bit(0, (void*)&dev->tbusy) != 0) {
     printk(KERN_ERR "%s: Transmitter access conflict.\n", dev->name);
     return 1;
  }
  if (set_bit(0, (void*)&p->lock)) {
	printk(KERN_ERR "%s: Queue was locked.\n", dev->name);
	return 1;
  }

  {
    short len = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN;
    struct tmd *tmdp;
    long flags;

#ifdef XMT_VIA_SKB
    if( (unsigned long) (skb->data + skb->len) > 0x1000000) {
#endif

      memcpy((char *) p->tmdbounce[p->tmdbouncenum] ,(char *)skb->data,
               (skb->len > T_BUF_SIZE) ? T_BUF_SIZE : skb->len);
      dev_kfree_skb (skb, FREE_WRITE);

      save_flags(flags);
      cli();

      tmdp = p->tmdhead + p->tmdnum;
      tmdp->u.buffer = (unsigned long ) p->tmdbounce[p->tmdbouncenum];
      p->tmdbouncenum = (p->tmdbouncenum + 1) & (TMDNUM - 1);

#ifdef XMT_VIA_SKB
    }
    else {
      save_flags(flags);
      cli();
 
      tmdp = p->tmdhead + p->tmdnum;
      tmdp->u.buffer = (unsigned long) skb->data;
      p->tmd_skb[p->tmdnum] = skb;
    }
#endif
    tmdp->blen = -len;

    tmdp->u.s.status = XMIT_OWN | XMIT_START | XMIT_END;
    writedatareg(CSR0_TDMD | CSR0_INEA); /* enable xmit & interrupt */

    p->xmit_queued = 1;
    p->tmdnum = (p->tmdnum + 1) & (TMDNUM-1);

    dev->tbusy = (p->tmdnum == p->tmdlast) ? 1 : 0;
    p->lock = 0;
    dev->trans_start = jiffies;

    restore_flags(flags);
  }

  return 0;
}

static struct enet_statistics *ni65_get_stats(struct device *dev)
{

#if 0
 int i;
 struct priv *p = (struct priv *) dev->priv;
 for(i=0;i<RMDNUM;i++) {
   struct rmd *rmdp = p->rmdhead + ((p->rmdnum + i) & (RMDNUM-1));
   printk("%02x ",rmdp->u.s.status);
 }
 printk("\n");
#endif

  return &((struct priv *) dev->priv)->stats;
}

static void set_multicast_list(struct device *dev)
{
	if(!ni65_lance_reinit(dev))
		printk(KERN_ERR "%s: Can't switch card into MC mode!\n",dev->name);
	dev->tbusy = 0;
}

#ifdef MODULE
static struct device dev_ni65 = {
  "        ",  /* "ni6510": device name inserted by net_init.c */
  0, 0, 0, 0,
  0x360, 9,   /* I/O address, IRQ */
  0, 0, 0, NULL, ni65_probe };

/* set: io,irq,dma or set it when calling insmod */
int irq=0;
int io=0;
int dma=0;

int init_module(void)
{
#if 0
  if(io <= 0x0 || irq < 2) {
    printk("ni65: Autoprobing not allowed for modules.\n");
    printk("ni65: Set symbols 'io' 'irq' and 'dma'\n");
    return -ENODEV;
  }
#endif
  dev_ni65.irq = irq;
  dev_ni65.dma = dma;
  dev_ni65.base_addr = io;
  if (register_netdev(&dev_ni65) != 0)
    return -EIO;
  return 0;
}

void cleanup_module(void)
{
  struct priv *p;
  p = (struct priv *) dev_ni65.priv;
  if(!p) {
    printk("Ooops .. no privat struct\n");
    return;
  }
  disable_dma(dev_ni65.dma);
  free_dma(dev_ni65.dma);
  release_region(dev_ni65.base_addr,cards[p->cardno].total_size);
  ni65_free_buffer(p);
  dev_ni65.priv = NULL;
  unregister_netdev(&dev_ni65);
}
#endif /* MODULE */

/*
 * END of ni65.c 
 */


