wanpipe_multppp.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

	flags = card->u.c.flags;
		
	/* If we get an interrupt with no network device, stop the interrupts
	 * and issue an error */
	if ((!dev || !dev->priv) && flags->interrupt_info_struct.interrupt_type != 
	    	COMMAND_COMPLETE_APP_INT_PEND){
		goto isr_done;
	}

	
	/* if critical due to peripheral operations
	 * ie. update() or getstats() then reset the interrupt and
	 * wait for the board to retrigger.
	 */
	if(test_bit(PERI_CRIT, (void*)&card->wandev.critical)) {
		flags->interrupt_info_struct.
					interrupt_type = 0;
		goto isr_done;
	}


	/* On a 508 Card, if critical due to if_send 
         * Major Error !!!
	 */
	if(card->hw.type != SDLA_S514) {
		if(test_bit(0, (void*)&card->wandev.critical)) {
			printk(KERN_INFO "%s: Critical while in ISR: %lx\n",
				card->devname, card->wandev.critical);
			goto isr_done;
		}
	}

	switch(flags->interrupt_info_struct.interrupt_type) {

		case RX_APP_INT_PEND:	/* 0x01: receive interrupt */
			rx_intr(card);
			break;

		case TX_APP_INT_PEND:	/* 0x02: transmit interrupt */
			flags->interrupt_info_struct.interrupt_permission &=
				 ~APP_INT_ON_TX_FRAME;

			wake_net_dev(dev);
			break;

		case COMMAND_COMPLETE_APP_INT_PEND:/* 0x04: cmd cplt */
			++ Intr_test_counter;
			break;

		case CHDLC_EXCEP_COND_APP_INT_PEND:	/* 0x20 */
			process_chdlc_exception(card);
			break;

		case GLOBAL_EXCEP_COND_APP_INT_PEND:
			process_global_exception(card);
			break;

		case TIMER_APP_INT_PEND:
			timer_intr(card);
			break;

		default:
			printk(KERN_INFO "%s: spurious interrupt 0x%02X!\n", 
				card->devname,
				flags->interrupt_info_struct.interrupt_type);
			printk(KERN_INFO "Code name: ");
			for(i = 0; i < 4; i ++)
				printk(KERN_INFO "%c",
					flags->global_info_struct.codename[i]); 
			printk(KERN_INFO "\nCode version: ");
			for(i = 0; i < 4; i ++)
				printk(KERN_INFO "%c", 
					flags->global_info_struct.codeversion[i]); 
			printk(KERN_INFO "\n");	
			break;
	}

isr_done:
	card->in_isr = 0;
	flags->interrupt_info_struct.interrupt_type = 0;
}

/*============================================================================
 * Receive interrupt handler.
 */
static void rx_intr (sdla_t* card)
{
	netdevice_t *dev;
	chdlc_private_area_t *chdlc_priv_area;
	SHARED_MEMORY_INFO_STRUCT *flags = card->u.c.flags;
	CHDLC_DATA_RX_STATUS_EL_STRUCT *rxbuf = card->u.c.rxmb;
	struct sk_buff *skb;
	unsigned len;
	unsigned addr = rxbuf->ptr_data_bfr;
	void *buf;
	int i,udp_type;
	
	if (rxbuf->opp_flag != 0x01) {
		printk(KERN_INFO 
			"%s: corrupted Rx buffer @ 0x%X, flag = 0x%02X!\n", 
			card->devname, (unsigned)rxbuf, rxbuf->opp_flag);
                printk(KERN_INFO "Code name: ");
                for(i = 0; i < 4; i ++)
                        printk(KERN_INFO "%c",
                                flags->global_info_struct.codename[i]);
                printk(KERN_INFO "\nCode version: ");
                for(i = 0; i < 4; i ++)
                        printk(KERN_INFO "%c",
                                flags->global_info_struct.codeversion[i]);
                printk(KERN_INFO "\n");


		/* Bug Fix: Mar 6 2000
                 * If we get a corrupted mailbox, it measn that driver 
                 * is out of sync with the firmware. There is no recovery.
                 * If we don't turn off all interrupts for this card
                 * the machine will crash. 
                 */
		printk(KERN_INFO "%s: Critical router failure ...!!!\n", card->devname);
		printk(KERN_INFO "Please contact Sangoma Technologies !\n");
		chdlc_set_intr_mode(card,0);	
		return;
	}

	dev = card->wandev.dev;

	if (!dev){ 
		goto rx_exit;
	}
	
#ifdef LINUX_2_4
	if (!netif_running(dev)){
		goto rx_exit;
	}
#else
	if (!dev->start){ 
		goto rx_exit;
	}
#endif

	chdlc_priv_area = dev->priv;

	if (rxbuf->error_flag){	
		goto rx_exit;
	}
	/* Take off two CRC bytes */

	if (rxbuf->frame_length < 7 || rxbuf->frame_length > 1506 ){
		goto rx_exit;
	}	

	len = rxbuf->frame_length - CRC_LENGTH;

	/* Allocate socket buffer */
	skb = dev_alloc_skb(len);

	if (skb == NULL) {
		if (net_ratelimit()){
			printk(KERN_INFO "%s: no socket buffers available!\n",
						card->devname);
		}
		++card->wandev.stats.rx_dropped;
		goto rx_exit;
	}

	/* Copy data to the socket buffer */
	if((addr + len) > card->u.c.rx_top + 1) {
		unsigned tmp = card->u.c.rx_top - addr + 1;
		buf = skb_put(skb, tmp);
		sdla_peek(&card->hw, addr, buf, tmp);
		addr = card->u.c.rx_base;
		len -= tmp;
	}
		
	buf = skb_put(skb, len);
	sdla_peek(&card->hw, addr, buf, len);

	skb->protocol = htons(ETH_P_WAN_PPP);

	card->wandev.stats.rx_packets ++;
#if defined(LINUX_2_1) || defined(LINUX_2_4)
	card->wandev.stats.rx_bytes += skb->len;
#endif
	udp_type = udp_pkt_type( skb, card );

	if(udp_type == UDP_CPIPE_TYPE) {
		if(store_udp_mgmt_pkt(UDP_PKT_FRM_NETWORK,
   				      card, skb, dev, chdlc_priv_area)) {
     		        flags->interrupt_info_struct.
						interrupt_permission |= 
							APP_INT_ON_TIMER; 
		}
	}else{
               	/* Pass it up the protocol stack */
                skb->dev = dev;
                skb->mac.raw  = skb->data;
                netif_rx(skb);
	}

rx_exit:
	/* Release buffer element and calculate a pointer to the next one */
	rxbuf->opp_flag = 0x00;
	card->u.c.rxmb = ++ rxbuf;
	if((void*)rxbuf > card->u.c.rxbuf_last){
		card->u.c.rxmb = card->u.c.rxbuf_base;
	}
}

/*============================================================================
 * Timer interrupt handler.
 * The timer interrupt is used for two purposes:
 *    1) Processing udp calls from 'cpipemon'.
 *    2) Reading board-level statistics for updating the proc file system.
 */
void timer_intr(sdla_t *card)
{
        netdevice_t* dev;
        chdlc_private_area_t* chdlc_priv_area = NULL;
        SHARED_MEMORY_INFO_STRUCT* flags = NULL;

        dev = card->wandev.dev; 
        chdlc_priv_area = dev->priv;

	if (chdlc_priv_area->timer_int_enabled & TMR_INT_ENABLED_CONFIG) {
		if (!config_chdlc(card)){
			chdlc_priv_area->timer_int_enabled &= ~TMR_INT_ENABLED_CONFIG;
		}
	}
	
	/* process a udp call if pending */
       	if(chdlc_priv_area->timer_int_enabled & TMR_INT_ENABLED_UDP) {
               	process_udp_mgmt_pkt(card, dev,
                       chdlc_priv_area);
		chdlc_priv_area->timer_int_enabled &= ~TMR_INT_ENABLED_UDP;
        }
	

	/* read the communications statistics if required */
	if(chdlc_priv_area->timer_int_enabled & TMR_INT_ENABLED_UPDATE) {
		update_comms_stats(card, chdlc_priv_area);
                if(!(-- chdlc_priv_area->update_comms_stats)) {
			chdlc_priv_area->timer_int_enabled &= 
				~TMR_INT_ENABLED_UPDATE;
		}
        }

	/* only disable the timer interrupt if there are no udp or statistic */
	/* updates pending */
        if(!chdlc_priv_area->timer_int_enabled) {
                flags = card->u.c.flags;
                flags->interrupt_info_struct.interrupt_permission &=
                        ~APP_INT_ON_TIMER;
        }
}

/*------------------------------------------------------------------------------
  Miscellaneous Functions
	- set_chdlc_config() used to set configuration options on the board
------------------------------------------------------------------------------*/

static int set_chdlc_config(sdla_t* card)
{

	CHDLC_CONFIGURATION_STRUCT cfg;

	memset(&cfg, 0, sizeof(CHDLC_CONFIGURATION_STRUCT));

	if(card->wandev.clocking)
		cfg.baud_rate = card->wandev.bps;

	cfg.line_config_options = (card->wandev.interface == WANOPT_RS232) ?
		INTERFACE_LEVEL_RS232 : INTERFACE_LEVEL_V35;

	cfg.modem_config_options	= 0;
	//API OPTIONS
	cfg.CHDLC_API_options		= DISCARD_RX_ERROR_FRAMES;
	cfg.modem_status_timer		= 100;
	cfg.CHDLC_protocol_options	= HDLC_STREAMING_MODE;
	cfg.percent_data_buffer_for_Tx  = 50;
	cfg.CHDLC_statistics_options	= (CHDLC_TX_DATA_BYTE_COUNT_STAT |
		CHDLC_RX_DATA_BYTE_COUNT_STAT);
	cfg.max_CHDLC_data_field_length	= card->wandev.mtu;

	cfg.transmit_keepalive_timer	= 0;
	cfg.receive_keepalive_timer	= 0;
	cfg.keepalive_error_tolerance	= 0;
	cfg.SLARP_request_timer		= 0;

	cfg.IP_address		= 0;
	cfg.IP_netmask		= 0;
	
	return chdlc_configure(card, &cfg);
}

/*============================================================================
 * Process global exception condition
 */
static int process_global_exception(sdla_t *card)
{
	CHDLC_MAILBOX_STRUCT* mbox = card->mbox;
	int err;

	mbox->buffer_length = 0;
	mbox->command = READ_GLOBAL_EXCEPTION_CONDITION;
	err = sdla_exec(mbox) ? mbox->return_code : CMD_TIMEOUT;

	if(err != CMD_TIMEOUT ){
	
		switch(mbox->return_code) {
         
	      	case EXCEP_MODEM_STATUS_CHANGE:

			printk(KERN_INFO "%s: Modem status change\n",
				card->devname);

			switch(mbox->data[0] & (DCD_HIGH | CTS_HIGH)) {
				case (DCD_HIGH):
					printk(KERN_INFO "%s: DCD high, CTS low\n",card->devname);
					break;
				case (CTS_HIGH):
                                        printk(KERN_INFO "%s: DCD low, CTS high\n",card->devname);
                                        break;
                                case ((DCD_HIGH | CTS_HIGH)):
                                        printk(KERN_INFO "%s: DCD high, CTS high\n",card->devname);
                                        break;
				default:
                                        printk(KERN_INFO "%s: DCD low, CTS low\n",card->devname);
                                        break;
			}

			if (!(mbox->data[0] & DCD_HIGH) || !(mbox->data[0] & DCD_HIGH)){
				//printk(KERN_INFO "Sending TERM Request Manually !\n");
				send_ppp_term_request(card->wandev.dev);
			}	
			break;

                case EXCEP_TRC_DISABLED:
                        printk(KERN_INFO "%s: Line trace disabled\n",
				card->devname);
                        break;

		case EXCEP_IRQ_TIMEOUT:
			printk(KERN_INFO "%s: IRQ timeout occurred\n",
				card->devname); 
			break;

                default:
                        printk(KERN_INFO "%s: Global exception %x\n",
				card->devname, mbox->return_code);
                        break;
                }
	}
	return 0;
}


/*============================================================================
 * Process chdlc exception condition
 */
static int process_chdlc_exception(sdla_t *card)
{
	CHDLC_MAILBOX_STRUCT* mb = card->mbox;
	int err;

	mb->buffer_length = 0;
	mb->command = READ_CHDLC_EXCEPTION_CONDITION;
	err = sdla_exec(mb) ? mb->return_code : CMD_TIMEOUT;
	if(err != CMD_TIMEOUT) {
	
		switch (err) {

		case EXCEP_LINK_ACTIVE:
			port_set_state(card, WAN_CONNECTED);
			break;

		case EXCEP_LINK_INACTIVE_MODEM:
			port_set_state(card, WAN_DISCONNECTED);
			break;

		case EXCEP_LOOPBACK_CONDITION:
			printk(KERN_INFO "%s: Loopback Condition Detected.\n",
						card->devname);
			break;

		case NO_CHDLC_EXCEP_COND_TO_REPORT:
			printk(KERN_INFO "%s: No exceptions reported.\n",
						card->devname);
			break;
		default:
			printk(KERN_INFO "%s: Exception Condition %x!\n",
					card->devname,err);
			break;
		}

	}
	return 0;
}


/*=============================================================================
 * Store a UDP management packet for later processing.
 */

static int store_udp_mgmt_pkt(char udp_pkt_src, sdla_t* card,
                                struct sk_buff *skb, netdevice_t* dev,
                                chdlc_private_area_t* chdlc_priv_area )
{
	int udp_pkt_stored = 0;

	if(!chdlc_priv_area->udp_pkt_lgth &&
	  (skb->len <= MAX_LGTH_UDP_MGNT_PKT)) {
        	chdlc_priv_area->udp_pkt_lgth = skb->len;
		chdlc_priv_area->udp_pkt_src = udp_pkt_src;
       		memcpy(chdlc_priv_area->udp_pkt_data, skb->data, skb->len);
		chdlc_priv_area->timer_int_enabled = TMR_INT_ENABLED_UDP;
		udp_pkt_stored = 1;
	}

	if(udp_pkt_src == UDP_PKT_FRM_STACK)
		wan_dev_kfree_skb(skb, FREE_WRITE);
	else
                wan_dev_kfree_skb(skb, FREE_READ);
	
	return(udp_pkt_stored);
}


/*=============================================================================
 * Process UDP management packet.
 */

static int process_udp_mgmt_pkt(sdla_t* card, netdevice_t* dev,
				chdlc_private_area_t* chdlc_priv_area ) 
{
	unsigned char *buf;
	unsigned int frames, len;
	struct sk_buff *new_skb;
	unsigned short buffer_length, real_len;
	unsigned long data_ptr;
	unsigned data_length;
	int udp_mgmt_req_valid = 1;
	CHDLC_MAILBOX_STRUCT *mb = card->mbox;
	SHARED_MEMORY_INFO_STRUCT *flags = card->u.c.flags;
	chdlc_udp_pkt_t *chdlc_udp_pkt;
	struct timeval tv;
	int err;
	char ut_char;

	chdlc_udp_pkt = (chdlc_udp_pkt_t *) chdlc_priv_area->udp_pkt_data;

	if(chdlc_priv_area->udp_pkt_src == UDP_PKT_FRM_NETWORK) {

		switch(chdlc_udp_pkt->cblock.command) {
			case READ_GLOBAL_STATISTICS:
			case READ_MODEM_STATUS:  
			case READ_CHDLC_LINK_STATUS:
			case CPIPE_ROUTER_UP_TIME:
			case READ_COMMS_ERROR_STATS:
			case READ_CHDLC_OPERATIONAL_STATS: