sdla_chdlc.c

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

	unsigned cmd = mb->command;

	switch (err) {

	case CMD_TIMEOUT:
		printk(KERN_INFO "%s: command 0x%02X timed out!\n",
			card->devname, cmd);
		break;

	case S514_BOTH_PORTS_SAME_CLK_MODE:
		if(cmd == SET_CHDLC_CONFIGURATION) {
			printk(KERN_INFO
			 "%s: Configure both ports for the same clock source\n",
				card->devname);
			break;
		}

	default:
		printk(KERN_INFO "%s: command 0x%02X returned 0x%02X!\n",
			card->devname, cmd, err);
	}

	return 0;
}

#if defined(LINUX_2_1) || defined(LINUX_2_4)
/********** Bottom Half Handlers ********************************************/

/* NOTE: There is no API, BH support for Kernels lower than 2.2.X.
 *       DO NOT INSERT ANY CODE HERE, NOTICE THE 
 *       PREPROCESSOR STATEMENT ABOVE, UNLESS YOU KNOW WHAT YOU ARE
 *       DOING */

static void chdlc_bh (netdevice_t * dev)
{
	chdlc_private_area_t* chan = dev->priv;
	sdla_t *card = chan->card;
	struct sk_buff *skb;

	if (atomic_read(&chan->bh_buff_used) == 0){
		clear_bit(0, &chan->tq_working);
		return;
	}

	while (atomic_read(&chan->bh_buff_used)){

		skb  = ((bh_data_t *)&chan->bh_head[chan->bh_read])->skb;

		if (skb != NULL){

			if (chan->common.sk == NULL || chan->common.func == NULL){
				++card->wandev.stats.rx_dropped;
				wan_dev_kfree_skb(skb, FREE_READ);
				chdlc_bh_cleanup(dev);
				continue;
			}

			if (chan->common.func(skb,dev,chan->common.sk) != 0){
				/* Sock full cannot send, queue us for another
                                 * try */
				atomic_set(&chan->common.receive_block,1);
				return;
			}else{
				chdlc_bh_cleanup(dev);
			}
		}else{
			chdlc_bh_cleanup(dev);
		}
	}	
	clear_bit(0, &chan->tq_working);

	return;
}

static int chdlc_bh_cleanup (netdevice_t *dev)
{
	chdlc_private_area_t* chan = dev->priv;

	((bh_data_t *)&chan->bh_head[chan->bh_read])->skb = NULL;

	if (chan->bh_read == MAX_BH_BUFF){
		chan->bh_read=0;
	}else{
		++chan->bh_read;	
	}

	atomic_dec(&chan->bh_buff_used);
	return 0;
}



static int bh_enqueue (netdevice_t *dev, struct sk_buff *skb)
{
	/* Check for full */
	chdlc_private_area_t* chan = dev->priv;
	sdla_t *card = chan->card;

	if (atomic_read(&chan->bh_buff_used) == (MAX_BH_BUFF+1)){
		++card->wandev.stats.rx_dropped;
		wan_dev_kfree_skb(skb, FREE_READ);
		return 1; 
	}

	((bh_data_t *)&chan->bh_head[chan->bh_write])->skb = skb;

	if (chan->bh_write == MAX_BH_BUFF){
		chan->bh_write=0;
	}else{
		++chan->bh_write;
	}

	atomic_inc(&chan->bh_buff_used);

	return 0;
}

/* END OF API BH Support */

#endif

/****** Interrupt Handlers **************************************************/

/*============================================================================
 * Cisco HDLC interrupt service routine.
 */
static void wpc_isr (sdla_t* card)
{
	netdevice_t* dev;
	SHARED_MEMORY_INFO_STRUCT* flags = NULL;
	int i;
	sdla_t *my_card;


	/* Check for which port the interrupt has been generated
	 * Since Secondary Port is piggybacking on the Primary
         * the check must be done here. 
	 */

	flags = card->u.c.flags;
	if (!flags->interrupt_info_struct.interrupt_type){
		/* Check for a second port (piggybacking) */
		if ((my_card = card->next)){
			flags = my_card->u.c.flags;
			if (flags->interrupt_info_struct.interrupt_type){
				card = my_card;
				card->isr(card);
				return;
			}
		}
	}

	flags = card->u.c.flags;
	card->in_isr = 1;
	dev = card->wandev.dev;
	
	/* If we get an interrupt with no network device, stop the interrupts
	 * and issue an error */
	if (!card->tty_opt && !dev && 
	    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)) {
		printk(KERN_INFO "ISR CRIT TO PERI\n");
		goto isr_done;
	}

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

	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;

#if defined(LINUX_2_1) || defined(LINUX_2_4)

		if (card->tty_opt){
			wanpipe_tty_trigger_poll(card);
			break;
		}

		if (dev && is_queue_stopped(dev)){
			if (card->u.c.usedby == API){
				start_net_queue(dev);
				wakeup_sk_bh(dev);
			}else{
				wake_net_dev(dev);
			}
		}
#else
		wake_net_dev(dev);
#endif
		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;
	return;
}

/*============================================================================
 * 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;
	}

	len  = rxbuf->frame_length;

#if defined(LINUX_2_4) || defined(LINUX_2_1)	
	if (card->tty_opt){

		if (rxbuf->error_flag){	
			goto rx_exit;
		}

		if (len <= CRC_LENGTH){
			goto rx_exit;
		}
		
		if (!card->u.c.async_mode){
			len -= CRC_LENGTH;
		}

		wanpipe_tty_receive(card,addr,len);
		goto rx_exit;
	}
#endif

	dev = card->wandev.dev;

	if (!dev){
		goto rx_exit;
	}

	if (!is_dev_running(dev))
		goto rx_exit;

	chdlc_priv_area = dev->priv;

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

	if (skb == NULL) {
		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_IP);

	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; 
		}
#if defined(LINUX_2_1) || defined(LINUX_2_4)
	} else if(card->u.c.usedby == API) {

		api_rx_hdr_t* api_rx_hdr;
       		skb_push(skb, sizeof(api_rx_hdr_t));
                api_rx_hdr = (api_rx_hdr_t*)&skb->data[0x00];
		api_rx_hdr->error_flag = rxbuf->error_flag;
     		api_rx_hdr->time_stamp = rxbuf->time_stamp;

                skb->protocol = htons(PVC_PROT);
     		skb->mac.raw  = skb->data;
		skb->dev      = dev;
               	skb->pkt_type = WAN_PACKET_DATA;

		bh_enqueue(dev, skb);

		if (!test_and_set_bit(0,&chdlc_priv_area->tq_working)){
			wanpipe_queue_tq(&chdlc_priv_area->common.wanpipe_task);
		        wanpipe_mark_bh();
		}
#endif
	}else{
		/* FIXME: we should check to see if the received packet is a 
                          multicast packet so that we can increment the multicast 
                          statistic
                          ++ chdlc_priv_area->if_stats.multicast;
		*/
               	/* 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;

        if ((dev = card->wandev.dev)==NULL){
		flags = card->u.c.flags;
                flags->interrupt_info_struct.interrupt_permission &=
                        ~APP_INT_ON_TIMER;
		return;
	}
	
        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_enab