sdla_x25.c

powerpc内核mpc8241linux系统下net驱动程序

		/* Invalid channel, discard packet */
		printk(KERN_INFO "%s: receiving on orphaned LCN %d!\n",
			card->devname, lcn);
		return;
	}

	chan = dev->priv;
	chan->i_timeout_sofar = jiffies;
	if (chan->drop_sequence)
	{
		if (!(qdm & 0x01)) chan->drop_sequence = 0;
		return;
	}

	skb = chan->rx_skb;
	if (skb == NULL)
	{
		/* Allocate new socket buffer */
		int bufsize = (qdm & 0x01) ? dev->mtu : len;

		skb = dev_alloc_skb(bufsize + dev->hard_header_len);
		if (skb == NULL)
		{
			printk(KERN_INFO "%s: no socket buffers available!\n",
				card->devname);
			chan->drop_sequence = 1;	/* set flag */
			++chan->ifstats.rx_dropped;
			return;
		}
		skb->dev = dev;
		skb->protocol = htons(chan->protocol);
		chan->rx_skb = skb;
	}

	if (skb_tailroom(skb) < len)
	{
		/* No room for the packet. Call off the whole thing! */
		dev_kfree_skb(skb);
		chan->rx_skb = NULL;
		if (qdm & 0x01) chan->drop_sequence = 1;

		printk(KERN_INFO "%s: unexpectedly long packet sequence "
			"on interface %s!\n", card->devname, dev->name);
		++chan->ifstats.rx_length_errors;
		return;
	}

	/* Append packet to the socket buffer */
	bufptr = skb_put(skb, len);
	memcpy(bufptr, rxmb->data, len);

	if (qdm & 0x01)
		return;		/* more data is comming */

	dev->last_rx = jiffies;		/* timestamp */
	chan->rx_skb = NULL;		/* dequeue packet */

	/* Decapsulate packet, if necessary */
	if (!skb->protocol && !wanrouter_type_trans(skb, dev))
	{
		/* can't decapsulate packet */
		dev_kfree_skb(skb);
		++chan->ifstats.rx_errors;
	}
	else
	{
		if( handle_IPXWAN(skb->data, card->devname, card->wandev.enable_IPX, card->wandev.network_number, skb->protocol))
		{
			if( card->wandev.enable_IPX )
			{
				if(chan_send(dev, skb))
				{
					chan->tx_skb = skb;
				}
				else
				{
					dev_kfree_skb(skb);
				}
			}
			else
			{
				/* FIXME: increment IPX packet dropped statistic */
			}
		}
		else
		{
			netif_rx(skb);
			++chan->ifstats.rx_packets;
			chan->ifstats.rx_bytes += skb->len;
		}
	}
}

/*============================================================================
 * Transmit interrupt handler.
 *	o Release socket buffer
 *	o Clear 'tbusy' flag
 */

static void tx_intr (sdla_t* card)
{
	struct device *dev;

	/* unbusy all devices and then dev_tint(); */
	for(dev = card->wandev.dev; dev; dev = dev->slave)
	{
		((x25_channel_t*)dev->priv)->devtint = dev->tbusy; 
		dev->tbusy = 0;
	}

}

/*============================================================================
 * Modem status interrupt handler.
 */
static void status_intr (sdla_t* card)
{
}

/*============================================================================
 * Network event interrupt handler.
 */
static void event_intr (sdla_t* card)
{
}

/*============================================================================
 * Spurious interrupt handler.
 * o print a warning
 * o 
 * If number of spurious interrupts exceeded some limit, then ???
 */
static void spur_intr (sdla_t* card)
{
	printk(KERN_INFO "%s: spurious interrupt!\n", card->devname);
}

/****** Background Polling Routines  ****************************************/

/*============================================================================
 * Main polling routine.
 * This routine is repeatedly called by the WANPIPE 'thread' to allow for
 * time-dependent housekeeping work.
 *
 * Notes:
 * 1. This routine may be called on interrupt context with all interrupts
 *    enabled. Beware!
 */

static void wpx_poll (sdla_t* card)
{
	unsigned long host_cpu_flags;

	disable_irq(card->hw.irq);
	++card->irq_dis_poll_count;

	if (test_and_set_bit(0, (void*)&card->wandev.critical)) 
	{
 		printk(KERN_INFO "%s: critical in polling!\n",card->devname);	
		save_flags(host_cpu_flags);
                cli();
		if ((!card->irq_dis_if_send_count) &&
                                (!(--card->irq_dis_poll_count)))
                        enable_irq(card->hw.irq);
                restore_flags(host_cpu_flags);
		return;
	}

	switch(card->wandev.state)
	{
		case WAN_CONNECTED:
			poll_active(card);
			break;

		case WAN_CONNECTING:
			poll_connecting(card);
			break;

		case WAN_DISCONNECTED:
			poll_disconnected(card);
	}
	card->wandev.critical = 0;
	save_flags(host_cpu_flags);
        cli();
        if ((!card->irq_dis_if_send_count) && (!(--card->irq_dis_poll_count)))
                enable_irq(card->hw.irq);
        restore_flags(host_cpu_flags);
}

/*============================================================================
 * Handle physical link establishment phase.
 * o if connection timed out, disconnect the link.
 */
static void poll_connecting (sdla_t* card)
{
	TX25Status* status = card->flags;

	if (status->gflags & X25_HDLC_ABM)
	{
		wanpipe_set_state(card, WAN_CONNECTED);
		x25_set_intr_mode(card, 0x83);	/* enable Rx interrupts */
		status->imask &= ~0x2;		/* mask Tx interupts */
	}
	else if ((jiffies - card->state_tick) > CONNECT_TIMEOUT)
	    disconnect(card);
}

/*============================================================================
 * Handle physical link disconnected phase.
 * o if hold-down timeout has expired and there are open interfaces, connect
 *   link.
 */
static void poll_disconnected (sdla_t* card)
{
	if (card->open_cnt && ((jiffies - card->state_tick) > HOLD_DOWN_TIME))
		connect(card);
}

/*============================================================================
 * Handle active link phase.
 * o fetch X.25 asynchronous events.
 * o kick off transmission on all interfaces.
 */
static void poll_active (sdla_t* card)
{
	struct device* dev;

	/* Fetch X.25 asynchronous events */
	x25_fetch_events(card);

	for (dev = card->wandev.dev; dev; dev = dev->slave)
	{
		x25_channel_t* chan = dev->priv;
		struct sk_buff* skb = chan->tx_skb;

		/* If there is a packet queued for transmission then kick
		 * the channel's send routine. When transmission is complete
		 * or if error has occurred, release socket buffer and reset
		 * 'tbusy' flag.
		 */
		if (skb && (chan_send(dev, skb) == 0))
		{
			chan->tx_skb = NULL;
			dev->tbusy = 0;
			dev_kfree_skb(skb);
		}

		/* If SVC has been idle long enough, close virtual circuit */

		if(( chan->svc )&&( chan->state == WAN_CONNECTED ))
		{
			if( (jiffies - chan->i_timeout_sofar) / HZ > chan->idle_timeout )
			{
				/* Close svc */
				printk(KERN_INFO "%s: Closing down Idle link %s on LCN %d\n",card->devname,chan->name,chan->lcn); 
				chan->i_timeout_sofar = jiffies;
				chan_disc(dev);
			}
		}
	}
}

/****** SDLA Firmware-Specific Functions *************************************
 * Almost all X.25 commands can unexpetedly fail due to so called 'X.25
 * asynchronous events' such as restart, interrupt, incoming call request,
 * call clear request, etc.  They can't be ignored and have to be dealt with
 * immediately.  To tackle with this problem we execute each interface command
 * in a loop until good return code is received or maximum number of retries
 * is reached.  Each interface command returns non-zero return code, an
 * asynchronous event/error handler x25_error() is called.
 */

/*============================================================================
 * Read X.25 firmware version.
 *	Put code version as ASCII string in str. 
 */
static int x25_get_version (sdla_t* card, char* str)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		mbox->cmd.command = X25_READ_CODE_VERSION;
		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
	} while (err && retry-- &&
		 x25_error(card, err, X25_READ_CODE_VERSION, 0));

	if (!err && str)
	{
		int len = mbox->cmd.length;
		memcpy(str, mbox->data, len);
		str[len] = '\0';
	}
	return err;
}

/*============================================================================
 * Configure adapter.
 */

static int x25_configure (sdla_t* card, TX25Config* conf)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		memcpy(mbox->data, (void*)conf, sizeof(TX25Config));
		mbox->cmd.length  = sizeof(TX25Config);
		mbox->cmd.command = X25_SET_CONFIGURATION;
		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
	} while (err && retry-- && x25_error(card, err, X25_SET_CONFIGURATION, 0));
	return err;
}

/*============================================================================
 * Get communications error statistics.
 */
static int x25_get_err_stats (sdla_t* card)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		mbox->cmd.command = X25_HDLC_READ_COMM_ERR;
		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
	} while (err && retry-- && x25_error(card, err, X25_HDLC_READ_COMM_ERR, 0));

	if (!err)
	{
		THdlcCommErr* stats = (void*)mbox->data;

		card->wandev.stats.rx_over_errors    = stats->rxOverrun;
		card->wandev.stats.rx_crc_errors     = stats->rxBadCrc;
		card->wandev.stats.rx_missed_errors  = stats->rxAborted;
		card->wandev.stats.tx_aborted_errors = stats->txAborted;
	}
	return err;
}

/*============================================================================
 * Get protocol statistics.
 */
static int x25_get_stats (sdla_t* card)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		mbox->cmd.command = X25_READ_STATISTICS;
		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
	} while (err && retry-- && x25_error(card, err, X25_READ_STATISTICS, 0));
	
	if (!err)
	{
		TX25Stats* stats = (void*)mbox->data;

		card->wandev.stats.rx_packets = stats->rxData;
		card->wandev.stats.tx_packets = stats->rxData;
	}
	return err;
}

/*============================================================================
 * Close HDLC link.
 */
static int x25_close_hdlc (sdla_t* card)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		mbox->cmd.command = X25_HDLC_LINK_CLOSE;
		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
	} while (err && retry-- && x25_error(card, err, X25_HDLC_LINK_CLOSE, 0));

	return err;
}

/*============================================================================
 * Open HDLC link.
 */
static int x25_open_hdlc (sdla_t* card)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		mbox->cmd.command = X25_HDLC_LINK_OPEN;
		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
	} while (err && retry-- && x25_error(card, err, X25_HDLC_LINK_OPEN, 0));
	
	return err;
}

/*============================================================================
 * Setup HDLC link.
 */
static int x25_setup_hdlc (sdla_t* card)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		mbox->cmd.command = X25_HDLC_LINK_SETUP;
		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
	} while (err && retry-- && x25_error(card, err, X25_HDLC_LINK_SETUP, 0));
	
	return err;
}

/*============================================================================
 * Set (raise/drop) DTR.
 */
static int x25_set_dtr (sdla_t* card, int dtr)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		mbox->data[0] = 0;
		mbox->data[2] = 0;
		mbox->data[1] = dtr ? 0x02 : 0x01;
		mbox->cmd.length  = 3;
		mbox->cmd.command = X25_SET_GLOBAL_VARS;
		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
	} while (err && retry-- && x25_error(card, err, X25_SET_GLOBAL_VARS, 0));

	return err;
}

/*============================================================================
 * Set interrupt mode.
 */
static int x25_set_intr_mode (sdla_t* card, int mode)
{
	TX25Mbox* mbox = card->mbox;
  	int retry = MAX_CMD_RETRY;
	int err;

	do
	{
		memset(&mbox->cmd, 0, sizeof(TX25Cmd));
		mbox->data[0] = mode;
		if (card->hw.fwid == SFID_X25_508)
		{
			mbox->data[1] = card->hw.irq;
			mbox->cmd.length = 2;