arcnet.c

powerpc内核mpc8241linux系统下net驱动程序

#endif

  /* Shut down the card */

  /* Disable TX if we need to */
  if (lp->en_dis_able_TX)
    (*lp->en_dis_able_TX)(dev, 0);

  (*lp->arcnet_reset)(dev, 3);	/* reset IRQ won't run if START=0 */
#if 0
  lp->intmask=0;
  SETMASK;		/* no IRQ's (except RESET, of course) */
  ACOMMAND(NOTXcmd);	/* stop transmit */
  ACOMMAND(NORXcmd);	/* disable receive */
#endif

  /* reset more flags */
  dev->interrupt=0;
#ifdef CONFIG_ARCNET_ETH
  lp->edev->interrupt=0;
#endif
#ifdef CONFIG_ARCNET_1051
  lp->sdev->interrupt=0;
#endif

  /* do NOT free lp->adev!!  It's static! */
  lp->adev=NULL;

#ifdef CONFIG_ARCNET_ETH
  /* free the ethernet-encap protocol device */
  lp->edev->priv=NULL;
  unregister_netdevice(lp->edev);
  kfree(lp->edev->name);
  kfree(lp->edev);
  lp->edev=NULL;
#endif

#ifdef CONFIG_ARCNET_1051
  /* free the RFC1051-encap protocol device */
  lp->sdev->priv=NULL;
  unregister_netdevice(lp->sdev);
  kfree(lp->sdev->name);
  kfree(lp->sdev);
  lp->sdev=NULL;
#endif

  /* Update the statistics here. (not necessary in ARCnet) */

  /* Decrease the use count */
  (*lp->openclose_device)(0);

  return 0;
}


/****************************************************************************
 *                                                                          *
 * Transmitter routines                                                     *
 *                                                                          *
 ****************************************************************************/

/* Generic error checking routine for arcnet??_send_packet
 */
static int
arcnet_send_packet_bad(struct sk_buff *skb, struct device *dev)
{
  struct arcnet_local *lp = (struct arcnet_local *)dev->priv;

  BUGMSG(D_DURING,"transmit requested (status=%Xh, inTX=%d)\n",
	 ARCSTATUS,lp->intx);

  if (lp->in_txhandler)
    {
      BUGMSG(D_NORMAL,"send_packet called while in txhandler!\n");
      lp->stats.tx_dropped++;
      return 1;
    }

  if (lp->intx>1)
    {
      BUGMSG(D_NORMAL,"send_packet called while intx!\n");
      lp->stats.tx_dropped++;
      return 1;
    }

  if (test_bit(0, (int *)&dev->tbusy))
    {
      /* If we get here, some higher level has decided we are broken.
	 There should really be a "kick me" function call instead. */
      int tickssofar = jiffies - dev->trans_start;

      int status=ARCSTATUS;

      if (tickssofar < TX_TIMEOUT)
	{
	  BUGMSG(D_DURING,"premature kickme! (status=%Xh ticks=%d o.skb=%ph numsegs=%d segnum=%d\n",
		 status,tickssofar,lp->outgoing.skb,
		 lp->outgoing.numsegs,
		 lp->outgoing.segnum);
	  return 1;
	}

      lp->intmask &= ~TXFREEflag;
      SETMASK;

      if (status&TXFREEflag)	/* transmit _DID_ finish */
	{
	  BUGMSG(D_NORMAL,"tx timeout - missed IRQ? (status=%Xh, ticks=%d, mask=%Xh, dest=%02Xh)\n",
		 status,tickssofar,lp->intmask,lp->lasttrans_dest);
	  lp->stats.tx_errors++;
	}
      else
	{
	  BUGMSG(D_EXTRA,"tx timed out (status=%Xh, tickssofar=%d, intmask=%Xh, dest=%02Xh)\n",
		 status,tickssofar,lp->intmask,lp->lasttrans_dest);
	  lp->stats.tx_errors++;
	  lp->stats.tx_aborted_errors++;

	  ACOMMAND(NOTXcmd);
	}

      if (lp->outgoing.skb)
	{
	  dev_kfree_skb(lp->outgoing.skb);
	  lp->stats.tx_dropped++;
	}
      lp->outgoing.skb=NULL;

#ifdef CONFIG_ARCNET_ETH
      lp->edev->tbusy=0;
#endif
#ifdef CONFIG_ARCNET_1051
      lp->sdev->tbusy=0;
#endif
      if (!test_and_clear_bit(0,(int *)&dev->tbusy))
	BUGMSG(D_EXTRA, "after timing out, tbusy was clear!\n");

      lp->txready=0;
      lp->sending=0;

      return 1;
    }

  if (lp->txready)	/* transmit already in progress! */
    {
      BUGMSG(D_NORMAL,"trying to start new packet while busy! (status=%Xh)\n",
	     ARCSTATUS);
      lp->intmask &= ~TXFREEflag;
      SETMASK;
      ACOMMAND(NOTXcmd); /* abort current send */
      (*lp->inthandler)(dev); /* fake an interrupt */
      lp->stats.tx_errors++;
      lp->stats.tx_fifo_errors++;
      lp->txready=0;	/* we definitely need this line! */

      return 1;
    }

  /* Block a timer-based transmit from overlapping.  This could better be
     done with atomic_swap(1, dev->tbusy), but set_bit() works as well. */
  if (test_and_set_bit(0, (int *)&lp->adev->tbusy))
    {
      BUGMSG(D_NORMAL,"transmitter called with busy bit set! (status=%Xh, inTX=%d, tickssofar=%ld)\n",
	     ARCSTATUS,lp->intx,jiffies-dev->trans_start);
      lp->stats.tx_errors++;
      lp->stats.tx_fifo_errors++;
      return -EBUSY;
    }
#ifdef CONFIG_ARCNET_1051
  lp->sdev->tbusy=1;
#endif
#ifdef CONFIG_ARCNET_ETH
  lp->edev->tbusy=1;
#endif

  return 0;
}


/* Called by the kernel in order to transmit a packet.
 */
static int
arcnetA_send_packet(struct sk_buff *skb, struct device *dev)
{
  struct arcnet_local *lp = (struct arcnet_local *)dev->priv;
  int bad,oldmask=0;
  struct Outgoing *out=&(lp->outgoing);

  lp->intx++;

  oldmask |= lp->intmask;
  lp->intmask=0;
  SETMASK;

  bad=arcnet_send_packet_bad(skb,dev);
  if (bad)
    {
      lp->intx--;
      lp->intmask=oldmask;
      SETMASK;
      return bad;
    }

  /* arcnet_send_packet_pad has already set tbusy - don't bother here. */

  lp->intmask = oldmask & ~TXFREEflag;
  SETMASK;

  out->length = 1 < skb->len ? skb->len : 1;
  out->hdr=(struct ClientData*)skb->data;
  out->skb=skb;

  BUGLVL(D_SKB) arcnet_dump_skb(dev,skb,"tx");

  out->hdr->sequence=(lp->sequence++);

  /* fits in one packet? */
  if (out->length-EXTRA_CLIENTDATA<=XMTU)
    {
      BUGMSG(D_DURING,"not splitting %d-byte packet. (split_flag=%d)\n",
	     out->length,out->hdr->split_flag);
      if (out->hdr->split_flag)
	BUGMSG(D_NORMAL,"short packet has split_flag set?! (split_flag=%d)\n",
	       out->hdr->split_flag);
      out->numsegs=1;
      out->segnum=1;
      (*lp->prepare_tx)(dev,
			((char *)out->hdr)+EXTRA_CLIENTDATA,
			sizeof(struct ClientData)-EXTRA_CLIENTDATA,
			((char *)skb->data)+sizeof(struct ClientData),
			out->length-sizeof(struct ClientData),
			out->hdr->daddr,1,0);

      /* done right away */
      lp->stats.tx_bytes += out->skb->len;
      dev_kfree_skb(out->skb);
      out->skb=NULL;

      if (arcnet_go_tx(dev,1))
	{
	  /* inform upper layers */
	  arcnet_tx_done(dev, lp);
	}
    }
  else			/* too big for one - split it */
    {
      int maxsegsize=XMTU-4;

      out->data=(u_char *)skb->data
	+ sizeof(struct ClientData);
      out->dataleft=out->length-sizeof(struct ClientData);
      out->numsegs=(out->dataleft+maxsegsize-1)/maxsegsize;
      out->segnum=0;

      BUGMSG(D_TX,"packet (%d bytes) split into %d fragments:\n",
	     out->length,out->numsegs);

      /* if a packet waiting, launch it */
      arcnet_go_tx(dev,1);

      if (!lp->txready)
	{
	  /* prepare a packet, launch it and prepare
	   * another.
	   */
	  arcnetA_continue_tx(dev);
	  if (arcnet_go_tx(dev,1))
	    {
	      arcnetA_continue_tx(dev);
	      arcnet_go_tx(dev,1);
	    }
	}

      /* if segnum==numsegs, the transmission is finished;
       * free the skb right away.
       */

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

  dev->trans_start=jiffies;
  lp->intx--;

  /* make sure we didn't ignore a TX IRQ while we were in here */
  lp->intmask |= TXFREEflag;
  SETMASK;

  return 0;
}


/* After an RFC1201 split packet has been set up, this function calls
 * arcnetAS_prepare_tx to load the next segment into the card.  This function
 * does NOT automatically call arcnet_go_tx.
 */
void arcnetA_continue_tx(struct device *dev)
{
  struct arcnet_local *lp = (struct arcnet_local *)dev->priv;
  int maxsegsize=XMTU-4;
  struct Outgoing *out=&(lp->outgoing);

  BUGMSG(D_DURING,"continue_tx called (status=%Xh, intx=%d, intxh=%d, intmask=%Xh\n",
	 ARCSTATUS,lp->intx,lp->in_txhandler,lp->intmask);

  if (lp->txready)
    {
      BUGMSG(D_NORMAL,"continue_tx: called with packet in buffer!\n");
      return;
    }

  if (out->segnum>=out->numsegs)
    {
      BUGMSG(D_NORMAL,"continue_tx: building segment %d of %d!\n",
	     out->segnum+1,out->numsegs);
    }

  if (!out->segnum)	/* first packet */
    out->hdr->split_flag=((out->numsegs-2)<<1)+1;
  else
    out->hdr->split_flag=out->segnum<<1;

  out->seglen=maxsegsize;
  if (out->seglen>out->dataleft) out->seglen=out->dataleft;

  BUGMSG(D_TX,"building packet #%d (%d bytes) of %d (%d total), splitflag=%d\n",
	 out->segnum+1,out->seglen,out->numsegs,
	 out->length,out->hdr->split_flag);

  (*lp->prepare_tx)(dev,((char *)out->hdr)+EXTRA_CLIENTDATA,
		    sizeof(struct ClientData)-EXTRA_CLIENTDATA,
		    out->data,out->seglen,out->hdr->daddr,1,0);

  out->dataleft-=out->seglen;
  out->data+=out->seglen;
  out->segnum++;
}


/* Actually start transmitting a packet that was placed in the card's
 * buffer by arcnetAS_prepare_tx.  Returns 1 if a Tx is really started.
 *
 * This should probably always be called with the INTMASK register set to 0,
 * so go_tx is not called recursively.
 *
 * The enable_irq flag determines whether to actually write INTMASK value
 * to the card; TXFREEflag is always OR'ed into the memory variable either
 * way.
 */
int arcnet_go_tx(struct device *dev,int enable_irq)
{
	struct arcnet_local *lp=(struct arcnet_local *)dev->priv;

	BUGMSG(D_DURING,"go_tx: status=%Xh, intmask=%Xh, txready=%d, sending=%d\n",
		ARCSTATUS,lp->intmask,lp->txready,lp->sending);

	if (lp->sending || !lp->txready)
	{
		if (enable_irq && lp->sending)
		{
			lp->intmask |= TXFREEflag;
			SETMASK;
		}
		return 0;
	}

	/* start sending */
	ACOMMAND(TXcmd|(lp->txready<<3));

	lp->stats.tx_packets++;
	lp->txready=0;
	lp->sending++;

	lp->lasttrans_dest=lp->lastload_dest;
	lp->lastload_dest=0;

	lp->intmask |= TXFREEflag;

	if (enable_irq)	SETMASK;

	return 1;
}


/****************************************************************************
 *                                                                          *
 * Interrupt handler                                                        *
 *                                                                          *
 ****************************************************************************/


/* The typical workload of the driver:  Handle the network interface
 * interrupts. Establish which device needs attention, and call the correct
 * chipset interrupt handler.
 */
void
arcnet_interrupt(int irq,void *dev_id,struct pt_regs *regs)
{
	struct device *dev = dev_id;
	struct arcnet_local *lp;

	if (dev==NULL)
	  {
	    BUGMSG(D_DURING, "arcnet: irq %d for unknown device.\n", irq);
	    return;
	  }

	BUGMSG(D_DURING,"in arcnet_interrupt\n");

	lp=(struct arcnet_local *)dev->priv;
	if (!lp)
	  {
	    BUGMSG(D_DURING, "arcnet: irq ignored.\n");
	    return;
	  }

	/* RESET flag was enabled - if !dev->start, we must clear it right
	 * away (but nothing else) since inthandler() is never called.
	 */

	if (!dev->start)
	  {
	    if (ARCSTATUS & RESETflag)
	      ACOMMAND(CFLAGScmd|RESETclear);
	    return;
	  }


	if (test_and_set_bit(0, (int *)&dev->interrupt))
	  {
	    BUGMSG(D_NORMAL,"DRIVER PROBLEM!  Nested arcnet interrupts!\n");
	    return;	/* don't even try. */
	  }
#ifdef CONFIG_ARCNET_1051
	if (lp->sdev)
	  lp->sdev->interrupt=1;
#endif
#ifdef CONFIG_ARCNET_ETH
	if (lp->edev)
	  lp->edev->interrupt=1;
#endif

	/* Call the "real" interrupt handler. */
	(*lp->inthandler)(dev);

#ifdef CONFIG_ARCNET_ETH
	if (lp->edev)
	  lp->edev->interrupt=0;
#endif
#ifdef CONFIG_ARCNET_1051
	if (lp->sdev)
	  lp->sdev->interrupt=0;
#endif
	if (!test_and_clear_bit(0, (int *)&dev->interrupt))
	  BUGMSG(D_NORMAL, "Someone cleared our dev->interrupt flag!\n");

}

void arcnet_tx_done(struct device *dev, struct arcnet_local *lp)
{
  if (dev->tbusy)
    {
#ifdef CONFIG_ARCNET_ETH
      lp->edev->tbusy=0;
#endif
#ifdef CONFIG_ARCNET_1051
      lp->sdev->tbusy=0;
#endif
      if (!test_and_clear_bit(0, (int *)&dev->tbusy))
	BUGMSG(D_NORMAL, "In arcnet_tx_done: Someone cleared our dev->tbusy"
	       " flag!\n");

      mark_bh(NET_BH);
    }
}


/****************************************************************************
 *                                                                          *
 * Receiver routines                                                        *
 *                                                                          *
 ****************************************************************************/

/*
 * This is a generic packet receiver that calls arcnet??_rx depending on the
 * protocol ID found.
 */

void arcnet_rx(struct arcnet_local *lp, u_char *arcsoft, short length, int saddr, int daddr)
{
  struct device *dev=lp->adev;

  BUGMSG(D_DURING,"received packet from %02Xh to %02Xh (%d bytes)\n",
	 saddr,daddr,length);

  /* call the right receiver for the protocol */
  switch (arcsoft[0])
    {
    case ARC_P_IP:
    case ARC_P_ARP:
    case ARC_P_RARP:
    case ARC_P_IPX:
    case ARC_P_NOVELL_EC:
      arcnetA_rx(lp->adev,arcsoft,length,saddr,daddr);
      break;
#ifdef CONFIG_ARCNET_ETH
    case ARC_P_ETHER:
      arcnetE_rx(lp->edev,arcsoft,length,saddr,daddr);
      break;
#endif
#ifdef CONFIG_ARCNET_1051
    case ARC_P_IP_RFC1051:
    case ARC_P_ARP_RFC1051:
      arcnetS_rx(lp->sdev,arcsoft,length,saddr,daddr);