arcnet.c

powerpc内核mpc8241linux系统下net驱动程序

  u_char daddr;
  short offset,length=skb->len+1;
  u_char proto=ARC_P_ETHER;

  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;
  SETMASK;

  if (length>XMTU)
    {
      BUGMSG(D_NORMAL,"MTU must be <= 493 for ethernet encap (length=%d).\n",
	     length);
      BUGMSG(D_NORMAL,"transmit aborted.\n");

      dev_kfree_skb(skb);
      lp->intx--;
      return 0;
    }

  BUGMSG(D_DURING,"starting tx sequence...\n");

  /* broadcasts have address FF:FF:FF:FF:FF:FF in etherspeak */
  if (((struct ethhdr*)(skb->data))->h_dest[0] == 0xFF)
    daddr=0;
  else
    daddr=((struct ethhdr*)(skb->data))->h_dest[5];

  /* load packet into shared memory */
  offset=512-length;
  if (length>MTU)		/* long/exception packet */
    {
      if (length<MinTU) offset-=3;
    }
  else			/* short packet */
    {
      offset-=256;
    }

  BUGMSG(D_DURING," length=%Xh, offset=%Xh\n",
	 length,offset);

  (*lp->prepare_tx)(dev, &proto, 1, skb->data, length-1, daddr, 0,
			   offset);

  dev_kfree_skb(skb);

  if (arcnet_go_tx(dev,1))
    {
      /* inform upper layers */
      arcnet_tx_done(lp->adev, lp);
    }

	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;
}


/* Packet receiver for ethernet-encap packets.
 */
static void
arcnetE_rx(struct device *dev,u_char *arcsoft,
	int length,u_char saddr, u_char daddr)
{
	struct arcnet_local *lp = (struct arcnet_local *)dev->priv;
	struct sk_buff *skb;

	BUGMSG(D_DURING,"it's an ethernet-encap packet (length=%d)\n",
			length);

       	skb = alloc_skb(length, GFP_ATOMIC);
       	if (skb == NULL) {
       		BUGMSG(D_NORMAL,"Memory squeeze, dropping packet.\n");
       		lp->stats.rx_dropped++;
       		return;
       	}

       	skb_put(skb,length);

       	skb->dev = dev;

       	memcpy(skb->data,(u_char *)arcsoft+1,length-1);

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

	lp->stats.rx_bytes += skb->len;
	skb->protocol=eth_type_trans(skb,dev);
        netif_rx(skb);
}

#endif /* CONFIG_ARCNET_ETH */

#ifdef CONFIG_ARCNET_1051
/****************************************************************************
 *                                                                          *
 * RFC1051 Support                                                          *
 *                                                                          *
 ****************************************************************************/

/* Initialize the arc0s device.
 */
static int arcnetS_init(struct device *dev)
{
  struct arcnet_local *lp = (struct arcnet_local *)dev->priv;

  arcnet_setup(dev);

  /* And now fill particular fields with arcnet values */
  dev->dev_addr[0]=lp->stationid;
  dev->hard_header_len=sizeof(struct S_ClientData);
  dev->mtu=512-sizeof(struct archdr)-dev->hard_header_len
    + S_EXTRA_CLIENTDATA;
  dev->open=arcnetS_open_close;
  dev->stop=arcnetS_open_close;
  dev->hard_start_xmit=arcnetS_send_packet;
  dev->hard_header=arcnetS_header;
  dev->rebuild_header=arcnetS_rebuild_header;

  return 0;
}


/* Bring up/down the arc0s device - we don't actually have to do anything,
 * since our parent arc0 handles the card I/O itself.
 */
static int arcnetS_open_close(struct device *dev)
{
  return 0;
}


/* Called by the kernel in order to transmit an RFC1051-type packet.
 */
static int
arcnetS_send_packet(struct sk_buff *skb, struct device *dev)
{
  struct arcnet_local *lp = (struct arcnet_local *)dev->priv;
  int bad,length;
  struct S_ClientData *hdr=(struct S_ClientData *)skb->data;

  lp->intx++;

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

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

  length = 1 < skb->len ? skb->len : 1;

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

  /* fits in one packet? */
  if (length-S_EXTRA_CLIENTDATA<=XMTU)
    {
      (*lp->prepare_tx)(dev,
			skb->data+S_EXTRA_CLIENTDATA,
			sizeof(struct S_ClientData)-S_EXTRA_CLIENTDATA,
			skb->data+sizeof(struct S_ClientData),
			length-sizeof(struct S_ClientData),
			hdr->daddr,0,0);

      /* done right away */
      dev_kfree_skb(skb);

      if (arcnet_go_tx(dev,1))
	{
	  /* inform upper layers */
	  arcnet_tx_done(lp->adev, lp);
	}
    }
  else			/* too big for one - not accepted */
    {
      BUGMSG(D_NORMAL,"packet too long (length=%d)\n",
	     length);
      dev_kfree_skb(skb);
      lp->stats.tx_dropped++;
      arcnet_tx_done(lp->adev, lp);
    }

  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;
}


/* Packet receiver for RFC1051 packets;
 */
static void
arcnetS_rx(struct device *dev,u_char *buf,
	   int length,u_char saddr, u_char daddr)
{
  struct arcnet_local *lp = (struct arcnet_local *)dev->priv;
  struct sk_buff *skb;
  struct S_ClientData *arcsoft,*soft;

  arcsoft=(struct S_ClientData *)(buf-S_EXTRA_CLIENTDATA);
  length+=S_EXTRA_CLIENTDATA;

  BUGMSG(D_DURING,"it's an RFC1051 packet (length=%d)\n",
	 length);

  {    /* was "if not split" in A protocol, S is never split */

    skb = alloc_skb(length, GFP_ATOMIC);
    if (skb == NULL) {
      BUGMSG(D_NORMAL,"Memory squeeze, dropping packet.\n");
      lp->stats.rx_dropped++;
      return;
    }
    soft=(struct S_ClientData *)skb->data;
    skb_put(skb,length);

    memcpy((u_char *)soft + sizeof(struct S_ClientData) - S_EXTRA_CLIENTDATA,
	   (u_char *)arcsoft + sizeof(struct S_ClientData) -S_EXTRA_CLIENTDATA,
	   length - sizeof(struct S_ClientData) + S_EXTRA_CLIENTDATA);
    soft->protocol_id=arcsoft->protocol_id;
    soft->daddr=daddr;
    soft->saddr=saddr;
    skb->dev = dev;  /* is already lp->sdev */

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

    lp->stats.rx_bytes += skb->len;
    skb->protocol=arcnetS_type_trans(skb,dev);
    netif_rx(skb);
  }
}


/* Create the ARCnet ClientData header for an arbitrary protocol layer
 *
 * saddr=NULL	means use device source address (always will anyway)
 * daddr=NULL	means leave destination address (eg unresolved arp)
 */
static int arcnetS_header(struct sk_buff *skb,struct device *dev,
			  unsigned short type,void *daddr,void *saddr,unsigned len)
{
  struct S_ClientData *head = (struct S_ClientData *)
    skb_push(skb,dev->hard_header_len);
  struct arcnet_local *lp=(struct arcnet_local *)(dev->priv);

  /* set the protocol ID according to RFC1051 */
  switch(type)
    {
    case ETH_P_IP:
      head->protocol_id=ARC_P_IP_RFC1051;
      BUGMSG(D_DURING,"S_header: IP_RFC1051 packet.\n");
      break;
    case ETH_P_ARP:
      head->protocol_id=ARC_P_ARP_RFC1051;
      BUGMSG(D_DURING,"S_header: ARP_RFC1051 packet.\n");
      break;
    default:
      BUGMSG(D_NORMAL,"I don't understand protocol %d (%Xh)\n",
	     type,type);
      lp->stats.tx_errors++;
      lp->stats.tx_aborted_errors++;
      return 0;
    }

  /*
   * Set the source hardware address.
   *
   * This is pretty pointless for most purposes, but it can help
   * in debugging.  saddr is stored in the ClientData header and
   * removed before sending the packet (since ARCnet does not allow
   * us to change the source address in the actual packet sent)
   */
  if(saddr)
    head->saddr=((u_char*)saddr)[0];
  else
    head->saddr=((u_char*)(dev->dev_addr))[0];

  /* supposedly if daddr is NULL, we should ignore it... */
  if(daddr)
    {
		head->daddr=((u_char*)daddr)[0];
		return dev->hard_header_len;
    }
  else
    head->daddr=0;	/* better fill one in anyway */

  return -dev->hard_header_len;
}


/* Rebuild the ARCnet ClientData header. This is called after an ARP
 * (or in future other address resolution) has completed on this
 * sk_buff. We now let ARP fill in the other fields.
 */
static int arcnetS_rebuild_header(struct sk_buff *skb)
{
  struct device *dev=skb->dev;
  struct S_ClientData *head = (struct S_ClientData *)skb->data;
  struct arcnet_local *lp=(struct arcnet_local *)(dev->priv);

  /*
   * Only ARP and IP are currently supported
   */

  if(head->protocol_id != ARC_P_IP_RFC1051)
    {
      BUGMSG(D_NORMAL,"I don't understand protocol type %d (%Xh) addresses!\n",
	     head->protocol_id,head->protocol_id);
      lp->stats.tx_errors++;
      lp->stats.tx_aborted_errors++;
      head->daddr=0;
      /*memcpy(eth->h_source, dev->dev_addr, dev->addr_len);*/
      return 0;
    }

  /*
   * Try to get ARP to resolve the header.
   */
#ifdef CONFIG_INET
  return arp_find(&(head->daddr),skb)? 1 : 0;
#else
  return 0;
#endif
}


/* Determine a packet's protocol ID.
 *
 * With ARCnet we have to convert everything to Ethernet-style stuff.
 */
unsigned short arcnetS_type_trans(struct sk_buff *skb,struct device *dev)
{
  struct S_ClientData *head;
  struct arcnet_local *lp=(struct arcnet_local *) (dev->priv);

  /* Pull off the arcnet header. */
  skb->mac.raw=skb->data;
  skb_pull(skb,dev->hard_header_len);
  head=(struct S_ClientData *)skb->mac.raw;

  if (head->daddr==0)
    skb->pkt_type=PACKET_BROADCAST;
  else if (dev->flags&IFF_PROMISC)
    {
      /* if we're not sending to ourselves :) */
      if (head->daddr != dev->dev_addr[0])
	skb->pkt_type=PACKET_OTHERHOST;
    }

  /* now return the protocol number */
  switch (head->protocol_id)
    {
    case ARC_P_IP_RFC1051:	return htons(ETH_P_IP);
    case ARC_P_ARP_RFC1051:	return htons(ETH_P_ARP);
    case ARC_P_ATALK:   return htons(ETH_P_ATALK); /* untested appletalk */
    default:
      lp->stats.rx_errors++;
      lp->stats.rx_crc_errors++;
      return 0;
    }

  return htons(ETH_P_IP);
}

#endif	/* CONFIG_ARCNET_1051 */


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

#ifdef MODULE

void cleanup_module(void)
{
  printk("Generic arcnet support removed.\n");
}

void arcnet_use_count(int open)
{
  if (open)
    MOD_INC_USE_COUNT;
  else
    MOD_DEC_USE_COUNT;
}

#else

void arcnet_use_count(int open)
{
}

struct device arcnet_devs[MAX_ARCNET_DEVS];
int arcnet_num_devs=0;
char arcnet_dev_names[MAX_ARCNET_DEVS][10];

__initfunc(void arcnet_init(void))
{
  int c;

  init_module();

  /* Don't register_netdev here. The chain hasn't been initialised. */

#ifdef CONFIG_ARCNET_COM90xx
  if ((!com90xx_explicit) && arcnet_num_devs < MAX_ARCNET_DEVS)
    {
      arcnet_devs[arcnet_num_devs].init=arc90xx_probe;
      arcnet_devs[arcnet_num_devs].name=
	(char *)&arcnet_dev_names[arcnet_num_devs];
      arcnet_num_devs++;
    }
#endif

  if (!arcnet_num_devs)
    {
      printk("Don't forget to load the chipset driver.\n");
      return;
    }

  /* Link into the device chain */

  /* Q: Should we put ourselves at the beginning or the end of the chain? */
  /* Probably the end, because we're not so fast, but... */

  for (c=0; c< (arcnet_num_devs-1); c++)
    arcnet_devs[c].next=&arcnet_devs[c+1];

  arcnet_devs[c].next=dev_base;
  dev_base=&arcnet_devs[0];

  /* Give names to those without them */

  for (c=0; c< arcnet_num_devs; c++)
    if (!arcnet_dev_names[c][0])
      arcnet_makename((char *)&arcnet_dev_names[c]);
}

#endif /* MODULE */


#ifdef MODULE
int init_module(void)
#else
__initfunc(static int init_module(void))
#endif
{
#ifdef ALPHA_WARNING
  BUGLVL(D_EXTRA)
    {
      printk("arcnet: ***\n");
      printk("arcnet: * Read arcnet.txt for important release notes!\n");
      printk("arcnet: *\n");
      printk("arcnet: * This is an ALPHA version!  (Last stable release: v2.56)  E-mail me if\n");
      printk("arcnet: * you have any questions, comments, or bug reports.\n");
      printk("arcnet: ***\n");
    }
#endif

  printk("%sAvailable protocols: ARCnet RFC1201"
#ifdef CONFIG_ARCNET_ETH
	 ", Ethernet-Encap"
#endif
#ifdef CONFIG_ARCNET_1051
	 ", ARCnet RFC1051"
#endif
#ifdef MODULE
	 ".\nDon't forget to load the chipset driver"
#endif
	".\n",version);
  return 0;
}


void arcnet_makename(char *device)
{
  struct device *dev;
  int arcnum;

  arcnum = 0;
  for (;;)
    {
      sprintf(device, "arc%d", arcnum);
      for (dev = dev_base; dev; dev=dev->next)
	if (dev->name != device && !strcmp(dev->name, device))
	  break;
      if (!dev)
	return;
      arcnum++;
    }
}