com90io.c

powerpc内核mpc8241linux系统下net驱动程序

static void
arc90io_inthandler(struct device *dev)
{
  struct arcnet_local *lp=(struct arcnet_local *)dev->priv;
  int ioaddr=dev->base_addr, status, boguscount = 3, didsomething;

  AINTMASK(0);

  BUGMSG(D_DURING,"in arc90io_inthandler (status=%Xh, intmask=%Xh)\n",
	 ARCSTATUS,lp->intmask);

  do
    {
      status = ARCSTATUS;
      didsomething=0;

      /* RESET flag was enabled - card is resetting and if RX
       * is disabled, it's NOT because we just got a packet.
       */
      if (status & RESETflag)
	{
	  BUGMSG(D_NORMAL,"spurious reset (status=%Xh)\n",
		 status);
	  arc90io_reset(dev,0);

	  /* all other flag values are just garbage */
	  break;
	}

      /* RX is inhibited - we must have received something. */
      if (status & lp->intmask & NORXflag)
	{
	  int recbuf=lp->recbuf=!lp->recbuf;
	  int oldaddr=0;

	  BUGMSG(D_DURING,"receive irq (status=%Xh)\n",
		 status);

	  /* enable receive of our next packet */
	  EnableReceiver();

	  if (lp->intx)
	    oldaddr=(inb(_ADDR_HI)<<8) | inb(_ADDR_LO);


	  /* Got a packet. */
	  arc90io_rx(dev,!recbuf);


	  if (lp->intx)
	    {
	      outb( (oldaddr >> 8),  _ADDR_HI);
	      outb( oldaddr & 0xff, _ADDR_LO);
	    }

	  didsomething++;
	}

      /* it can only be an xmit-done irq if we're xmitting :) */
      /*if (status&TXFREEflag && !lp->in_txhandler && lp->sending)*/
      if (status & lp->intmask & TXFREEflag)
	{
	  struct Outgoing *out=&(lp->outgoing);
	  int was_sending=lp->sending;

	  lp->intmask &= ~TXFREEflag;

	  lp->in_txhandler++;
	  if (was_sending) lp->sending--;

	  BUGMSG(D_DURING,"TX IRQ (stat=%Xh, numsegs=%d, segnum=%d, skb=%ph)\n",
		 status,out->numsegs,out->segnum,out->skb);

	  if (was_sending && !(status&TXACKflag))
	    {
	      if (lp->lasttrans_dest != 0)
		{
		  BUGMSG(D_EXTRA,"transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
			 status,lp->lasttrans_dest);
		  lp->stats.tx_errors++;
		  lp->stats.tx_carrier_errors++;
		}
	      else
		{
		  BUGMSG(D_DURING,"broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
			 status,
			 lp->lasttrans_dest);
		}
	    }

	  /* send packet if there is one */
	  arcnet_go_tx(dev,0);
	  didsomething++;

	  if (lp->intx)
	    {
	      BUGMSG(D_DURING,"TXDONE while intx! (status=%Xh, intx=%d)\n",
		     ARCSTATUS,lp->intx);
	      lp->in_txhandler--;
	      continue;
	    }

	  if (!lp->outgoing.skb)
	    {
	      BUGMSG(D_DURING,"TX IRQ done: no split to continue.\n");

	      /* inform upper layers */
	      if (!lp->txready) arcnet_tx_done(dev, lp);
	      lp->in_txhandler--;
	      continue;
	    }

	  /* if more than one segment, and not all segments
	   * are done, then continue xmit.
	   */
	  if (out->segnum<out->numsegs)
	    arcnetA_continue_tx(dev);
	  arcnet_go_tx(dev,0);

	  /* if segnum==numsegs, the transmission is finished;
	   * free the skb.
	   */
	  if (out->segnum>=out->numsegs)
	    {
	      /* transmit completed */
	      out->segnum++;
	      if (out->skb)
		{
		  lp->stats.tx_bytes += out->skb->len;
		  dev_kfree_skb(out->skb);
		}
	      out->skb=NULL;

	      /* inform upper layers */
	      if (!lp->txready) arcnet_tx_done(dev, lp);
	    }
	  didsomething++;

	  lp->in_txhandler--;
	}
      else if (lp->txready && !lp->sending && !lp->intx)
	{
	  BUGMSG(D_NORMAL,"recovery from silent TX (status=%Xh)\n",
		 status);
	  arcnet_go_tx(dev,0);
	  didsomething++;
	}

#ifdef DETECT_RECONFIGS
      if (status & (lp->intmask) & RECONflag)
	{
	  ACOMMAND(CFLAGScmd|CONFIGclear);
	  lp->stats.tx_carrier_errors++;

#ifdef SHOW_RECONFIGS
	  BUGMSG(D_NORMAL,"Network reconfiguration detected"
		 " (status=%Xh, config=%X)\n",
		 status,lp->config);
#endif /* SHOW_RECONFIGS */

#ifdef RECON_THRESHOLD
	  /* is the RECON info empty or old? */
	  if (!lp->first_recon || !lp->last_recon ||
	      jiffies-lp->last_recon > HZ*10)
	    {
	      if (lp->network_down)
		BUGMSG(D_NORMAL,"reconfiguration detected: cabling restored?\n");
	      lp->first_recon=lp->last_recon=jiffies;
	      lp->num_recons=lp->network_down=0;

	      BUGMSG(D_DURING,"recon: clearing counters.\n");
	    }
	  else /* add to current RECON counter */
	    {
	      lp->last_recon=jiffies;
	      lp->num_recons++;

	      BUGMSG(D_DURING,"recon: counter=%d, time=%lds, net=%d\n",
		     lp->num_recons,
		     (lp->last_recon-lp->first_recon)/HZ,
		     lp->network_down);

	      /* if network is marked up;
	       * and first_recon and last_recon are 60+ sec
	       *   apart;
	       * and the average no. of recons counted is
	       *   > RECON_THRESHOLD/min;
	       * then print a warning message.
	       */
	      if (!lp->network_down
		  && (lp->last_recon-lp->first_recon)<=HZ*60
		  && lp->num_recons >= RECON_THRESHOLD)
		{
		  lp->network_down=1;
		  BUGMSG(D_NORMAL,"many reconfigurations detected: cabling problem?\n");
		}
	      else if (!lp->network_down
		       && lp->last_recon-lp->first_recon > HZ*60)
		{
		  /* reset counters if we've gone for
		   * over a minute.
		   */
		  lp->first_recon=lp->last_recon;
		  lp->num_recons=1;
		}
	    }
	}
      else if (lp->network_down && jiffies-lp->last_recon > HZ*10)
	{
	  if (lp->network_down)
	    BUGMSG(D_NORMAL,"cabling restored?\n");
	  lp->first_recon=lp->last_recon=0;
	  lp->num_recons=lp->network_down=0;

	  BUGMSG(D_DURING,"not recon: clearing counters anyway.\n");
#endif
	}
#endif /* DETECT_RECONFIGS */
    } while (--boguscount && didsomething);

  BUGMSG(D_DURING,"net_interrupt complete (status=%Xh, count=%d)\n",
	 ARCSTATUS,boguscount);
  BUGMSG(D_DURING,"\n");

  SETMASK;	/* put back interrupt mask */
}


/* A packet has arrived; grab it from the buffers and pass it to the generic
 * arcnet_rx routing to deal with it.
 */

static void
arc90io_rx(struct device *dev,int recbuf)
{
  struct arcnet_local *lp = (struct arcnet_local *)dev->priv;
  int ioaddr=dev->base_addr;
  union ArcPacket packetbuf;
  union ArcPacket *arcpacket=&packetbuf;
  u_char *arcsoft;
  short length,offset;
  u_char daddr,saddr;

  lp->stats.rx_packets++;

  get_whole_buffer(dev,recbuf*512,4,(char *)arcpacket);

  saddr=arcpacket->hardheader.source;

  /* if source is 0, it's a "used" packet! */
  if (saddr==0)
    {
      BUGMSG(D_NORMAL,"discarding old packet. (status=%Xh)\n",
	     ARCSTATUS);
      lp->stats.rx_errors++;
      return;
    }
  /* Set source address to zero to mark it as old */

  put_buffer_byte(dev,recbuf*512,0);

  arcpacket->hardheader.source=0;

  daddr=arcpacket->hardheader.destination;

  if (arcpacket->hardheader.offset1) /* Normal Packet */
    {
      offset=arcpacket->hardheader.offset1;
      arcsoft=&arcpacket->raw[offset];
      length=256-offset;
    }
  else		/* ExtendedPacket or ExceptionPacket */
    {
      offset=arcpacket->hardheader.offset2;
      arcsoft=&arcpacket->raw[offset];
      length=512-offset;
    }

  get_whole_buffer(dev,recbuf*512+offset,length,(char *)arcpacket+offset);

  arcnet_rx(lp, arcsoft, length, saddr, daddr);

  BUGLVL(D_RX) arcnet_dump_packet(lp->adev,arcpacket->raw,length>240,"rx");
}


/* Given an skb, copy a packet into the ARCnet buffers for later transmission
 * by arcnet_go_tx.
 */
static void
arc90io_prepare_tx(struct device *dev,u_char *hdr,int hdrlen,
		    char *data,int length,int daddr,int exceptA, int offset)
{
  struct arcnet_local *lp = (struct arcnet_local *)dev->priv;

  lp->txbuf=lp->txbuf^1;	/* XOR with 1 to alternate between 2 and 3 */

  length+=hdrlen;

  BUGMSG(D_TX,"arcnetAS_prep_tx: hdr:%ph, length:%d, data:%ph\n",
	 hdr,length,data);

  put_buffer_byte(dev, lp->txbuf*512+1, daddr);

  /* load packet into shared memory */
  if (length<=MTU)	/* Normal (256-byte) Packet */
    put_buffer_byte(dev, lp->txbuf*512+2, offset=offset?offset:256-length);

  else if (length>=MinTU || offset)	/* Extended (512-byte) Packet */
    {
      put_buffer_byte(dev, lp->txbuf*512+2, 0);
      put_buffer_byte(dev, lp->txbuf*512+3, offset=offset?offset:512-length);
    }
  else if (exceptA)		/* RFC1201 Exception Packet */
    {
      put_buffer_byte(dev, lp->txbuf*512+2, 0);
      put_buffer_byte(dev, lp->txbuf*512+3, offset=512-length-4);

      /* exception-specific stuff - these four bytes
       * make the packet long enough to fit in a 512-byte
       * frame.
       */

      put_buffer_byte(dev, lp->txbuf*512+offset,hdr[0]);
      put_whole_buffer(dev, lp->txbuf*512+offset+1,3,"\377\377\377");
      offset+=4;
    }
  else				/* "other" Exception packet */
    {
      /* RFC1051 - set 4 trailing bytes to 0 */

      put_whole_buffer(dev,lp->txbuf*512+508,4,"\0\0\0\0");

      /* now round up to MinTU */
      put_buffer_byte(dev, lp->txbuf*512+2, 0);
      put_buffer_byte(dev, lp->txbuf*512+3, offset=512-MinTU);
    }

  /* copy the packet into ARCnet shmem
   *  - the first bytes of ClientData header are skipped
   */

  put_whole_buffer(dev, 512*lp->txbuf+offset, hdrlen,(u_char *)hdr);
  put_whole_buffer(dev, 512*lp->txbuf+offset+hdrlen,length-hdrlen,data);

  BUGMSG(D_DURING,"transmitting packet to station %02Xh (%d bytes)\n",
	 daddr,length);

  lp->lastload_dest=daddr;
  lp->txready=lp->txbuf;	/* packet is ready for sending */
}


/****************************************************************************
 *                                                                          *
 * Kernel Loadable Module Support                                           *
 *                                                                          *
 ****************************************************************************/


#ifdef MODULE

static struct device *cards[16]={NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,
			  NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL};


int init_module(void)
{
  struct device *dev=cards[0];

  cards[0]=dev=(struct device *)kmalloc(sizeof(struct device), GFP_KERNEL);
  if (!dev)
    return -ENOMEM;

  memset(dev, 0, sizeof(struct device));

  dev->name=(char *)kmalloc(9, GFP_KERNEL);
  if (!dev->name)
    {
      kfree(dev);
      return -ENOMEM;
    }
  dev->init=arc90io_probe;

  if (device)
    strcpy(dev->name,device);
  else arcnet_makename(dev->name);

  dev->base_addr=io;
  dev->irq=irq;

  if (dev->irq==2) dev->irq=9;

  if (register_netdev(dev) != 0)
    return -EIO;

  /* Increase use count of arcnet.o */
  arcnet_use_count(1);
  return 0;
}

void cleanup_module(void)
{
  struct device *dev=cards[0];
  int ioaddr=dev->base_addr;

  if (dev->start) (*dev->stop)(dev);

  /* Flush TX and disable RX */
  if (ioaddr)
    {
      AINTMASK(0);		/* disable IRQ's */
      ACOMMAND(NOTXcmd);	/* stop transmit */
      ACOMMAND(NORXcmd);	/* disable receive */

      /* Set the thing back to MMAP mode, in case the old
	         driver is loaded later */
      outb( (inb(_CONFIG)&~IOMAPflag),_CONFIG);
    }

  if (dev->irq)
    {
      free_irq(dev->irq,dev);
    }

  if (dev->base_addr) release_region(dev->base_addr,ARCNET_TOTAL_SIZE);
  unregister_netdev(dev);
  kfree(dev->priv);
  dev->priv = NULL;

  /* Decrease use count of arcnet.o */
  arcnet_use_count(0);
}

#else

__initfunc(void com90io_setup (char *str, int *ints))
{
  struct device *dev;

  if (arcnet_num_devs == MAX_ARCNET_DEVS)
    {
      printk("com90xx IO-MAP: Too many ARCnet devices registered (max %d).\n",
	     MAX_ARCNET_DEVS);
      return;
    }

  dev=&arcnet_devs[arcnet_num_devs];

  if (ints[0] < 1)
    {
      printk("com90xx IO-MAP: You must give an IO address.\n");
      return;
    }

  dev->init=arc90io_probe;

  switch(ints[0])
    {
    case 3: /* ERROR */
      printk("com90xx IO-MAP: Too many arguments.\n");

    case 2: /* IRQ */
      dev->irq=ints[2];

    case 1: /* IO address */
      dev->base_addr=ints[1];
    }

  dev->name = (char *)&arcnet_dev_names[arcnet_num_devs];

  if (str)
    strncpy(dev->name, str, 9);

  arcnet_num_devs++;
}

#endif /* MODULE */