pt.c

powerpc内核mpc8241linux系统下net驱动程序

        {
            if (request_dma(dev->dma, "pt"))
            {
                free_irq(dev->irq, dev);
                return -EAGAIN;
            }
        }

         /* Reset hardware */
         chipset_init(dev);
     }
     lp->tstate = IDLE;

     if (dev->base_addr & CHANA)
     {
         scc_init(dev);
         scc_init(dev->next);
     }
     /* Save a copy of register RR0 for comparing with later on */
     /* We always put 0 in zero count */
     lp->saved_RR0 = rdscc(lp->cardbase, lp->base + CTL, R0) & ~ZCOUNT;

    /* master interrupt enable */
    save_flags(flags);
    cli();
    wrtscc(lp->cardbase, lp->base + CTL, R9, MIE | NV);
    outb_p( pt_sercfg |= PT_EI, lp->cardbase + INT_CFG);
    restore_flags(flags);

    lp->open_time = jiffies;

    dev->tbusy = 0;
    dev->interrupt = 0;
    dev->start = 1;
    first_time = 0;

    MOD_INC_USE_COUNT;

    return 0;
} /* pt_open() */

static int pt_send_packet(struct sk_buff *skb, struct device *dev)
{
	struct pt_local *lp = (struct pt_local *) dev->priv;

#ifdef PT_DEBUG
	printk(KERN_DEBUG "PT: pt_send_packet(): (%d)\n", lp->base & CHANA);
#endif
	hardware_send_packet(lp, skb);
	dev->trans_start = jiffies;

	return 0;
}



/* The inverse routine to pt_open() */
static int pt_close(struct device *dev)
{
	unsigned long flags;
	struct pt_local *lp = dev->priv;
	struct sk_buff *ptr = NULL;
	int cmd;

	cmd = lp->base + CTL;

	save_flags(flags);
	cli();

	/* Reset SCC or channel */
	chipset_init(dev);
	disable_dma(lp->dmachan);

	lp->open_time = 0;
	dev->tbusy = 1;
	dev->start = 0;

	/* Free any buffers left in the hardware transmit queue */
	while ((ptr = skb_dequeue(&lp->sndq)) != NULL)
		kfree_skb(ptr);

	restore_flags(flags);

#ifdef PT_DEBUG
	printk(KERN_DEBUG "PT: pt_close(): Closing down channel (%d).\n", lp->base & CHANA);
#endif

	MOD_DEC_USE_COUNT;

	return 0;
} /* pt_close() */


static int pt_ioctl(struct device *dev, struct ifreq *ifr, int cmd)
{
    unsigned long flags;
    struct pt_req rq;
    struct pt_local *lp = (struct pt_local *) dev->priv;

    int ret = verify_area(VERIFY_WRITE, ifr->ifr_data, sizeof(struct pt_req));
    if (ret)
	return ret;

    if (cmd != SIOCDEVPRIVATE)
        return -EINVAL;

    copy_from_user(&rq, ifr->ifr_data, sizeof(struct pt_req));

    switch (rq.cmd) {
    case SIOCSPIPARAM:

	if (!suser())
	    return -EPERM;
	save_flags(flags);
	cli();
	lp->txdelay = rq.txdelay;
	lp->persist = rq.persist;
	lp->slotime = rq.slotime;
	lp->squeldelay = rq.squeldelay;
	lp->clockmode = rq.clockmode;
	lp->speed = rq.speed;
	pt_open(&pt0a);
	restore_flags(flags);
	ret = 0;
	break;

    case SIOCSPIDMA:

	if (!suser())
	    return -EPERM;
	ret = 0;
	if (dev->base_addr & CHANA) {   /* if A channel */
	   if (rq.dmachan < 1 || rq.dmachan > 3)
		return -EINVAL;
	   save_flags(flags);
	   cli();
	   pt_close(dev);
	   free_dma(lp->dmachan);
	   dev->dma = lp->dmachan = rq.dmachan;
	   if (request_dma(lp->dmachan,"pt"))
		ret = -EAGAIN;
	   pt_open(dev);
	   restore_flags(flags);
	}
	break;

    case SIOCSPIIRQ:
	ret = -EINVAL;      /* add this later */
	break;

    case SIOCGPIPARAM:
    case SIOCGPIDMA:
    case SIOCGPIIRQ:

	rq.speed = lp->speed;
	rq.txdelay = lp->txdelay;
	rq.persist = lp->persist;
	rq.slotime = lp->slotime;
	rq.squeldelay = lp->squeldelay;
	rq.clockmode = lp->clockmode;
	rq.dmachan = lp->dmachan;
	rq.irq = dev->irq;
	copy_to_user(ifr->ifr_data, &rq, sizeof(struct pt_req));
	ret = 0;
	break;

    default:
	ret = -EINVAL;
    }
    return ret;
}

/*
 *	Get the current statistics.
 *	This may be called with the card open or closed. 
 */
 
static struct net_device_stats *pt_get_stats(struct device *dev)
{
	struct pt_local *lp = (struct pt_local *) dev->priv;
	return &lp->stats;
}


/*
 * Local variables:
 *  compile-command: "gcc -D__KERNEL__ -I/usr/src/linux/net/inet -Wall -Wstrict-prototypes -O6 -m486 -c skeleton.c"
 *  version-control: t
 *  kept-new-versions: 5
 *  tab-width: 4
 * End:
 */


static void tdelay(struct pt_local *lp, int time)
{
	/* For some reason, we turn off the Tx interrupts here! */
	if (!lp->dmachan)
		wrtscc(lp->cardbase, lp->base + CTL, R1, INT_ALL_Rx | EXT_INT_ENAB);

	if (lp->base & CHANA) 
	{
		outb_p(time & 0xff, lp->cardbase + TMR1);
		outb_p((time >> 8)&0xff, lp->cardbase + TMR1);
	}
	else
	{
		outb_p(time & 0xff, lp->cardbase + TMR2);
		outb_p((time >> 8)&0xff, lp->cardbase + TMR2);
	}
} /* tdelay */


static void pt_txisr(struct pt_local *lp)
{
	unsigned long flags;
	int cmd;
	unsigned char c;

	save_flags(flags);
	cli();
	cmd = lp->base + CTL;

#ifdef PT_DEBUG
	printk(KERN_DEBUG "PT: pt_txisr(): tstate = %d (%d).\n", lp->tstate, lp->base & CHANA);
#endif

	switch (lp->tstate)
	{
	case CRCOUT:
	    lp->tstate = FLAGOUT;
	    tdelay(lp, lp->squeldelay);
	    restore_flags(flags);
	    return;

	case IDLE:
	    /* Transmitter idle. Find a frame for transmission */
	    if ((lp->sndbuf = skb_dequeue(&lp->sndq)) == NULL)
	    {
	        /* Nothing to send - return to receive mode
	         * Tx off now - flag should have gone
	         */
	        pt_rts(lp, OFF);

	        restore_flags(flags);
	        return;
	    }
	    if (!lp->dmachan)
	    {
		    lp->txptr = lp->sndbuf->data;
		    lp->txptr++;		/* Ignore KISS control byte */
		    lp->txcnt = (int) lp->sndbuf->len - 1;
		}
	    /* If a buffer to send, drop though here */

	case DEFER:
	    /* Check DCD - debounce it */
	    /* See Intel Microcommunications Handbook p2-308 */
	    wrtscc(lp->cardbase, cmd, R0, RES_EXT_INT);
	    wrtscc(lp->cardbase, cmd, R0, RES_EXT_INT);
	    if ((rdscc(lp->cardbase, cmd, R0) & DCD) != 0)
	    {
	        lp->tstate = DEFER;
	        tdelay(lp, 100);
	        /* DEFER until DCD transition or timeout */
	        wrtscc(lp->cardbase, cmd, R15, DCDIE);
	        restore_flags(flags);
	        return;
	    }
	    if (random() > lp->persist)
	    {
	        lp->tstate = DEFER;
	        tdelay(lp, lp->slotime);
	        restore_flags(flags);
	        return;
	    }
	    pt_rts(lp, ON);		/* Tx on */
	    if (lp->dmachan)
	    	wrtscc(lp->cardbase, cmd, R5, TxCRC_ENAB | RTS | Tx8);
	    lp->tstate = ST_TXDELAY;
	    tdelay(lp, lp->txdelay);
	    restore_flags(flags);
	    return;

	case ACTIVE:
	    /* Here we are actively sending a frame */
	    if (lp->txcnt--)
	    {
	        /* XLZ - checkout Gracilis PT code to see if the while
	         * loop is better or not.
	         */
	        c = *lp->txptr++;
	        /* next char is gone */
	        wrtscc(lp->cardbase, cmd, R8, c);
	        /* stuffing a char satisfies interrupt condition */
	    } else {
	        /* No more to send */
	        kfree_skb(lp->sndbuf);
	        lp->sndbuf = NULL;
	        if ((rdscc(lp->cardbase, cmd, R0) & TxEOM))
	        {
	            /* Did we underrun */
	            lp->stats.tx_errors++;
	            lp->stats.tx_fifo_errors++;
	            wrtscc(lp->cardbase, cmd, R0, SEND_ABORT);
	            lp->tstate = FLAGOUT;
	            tdelay(lp, lp->squeldelay);
	            restore_flags(flags);
	            return;
	        }
	        lp->tstate = UNDERRUN;
	        /* Send flags on underrun */
	       if (lp->nrzi)
	       {
	           wrtscc(lp->cardbase, cmd, R10, CRCPS | NRZI);
	       } else {
	           wrtscc(lp->cardbase, cmd, R10, CRCPS | NRZ);
	       }
	       /* Reset Tx interrupt pending */
	       wrtscc(lp->cardbase, cmd, R0, RES_Tx_P);
	   }
	   restore_flags(flags);
	   return;
	default:
		printk(KERN_ERR "PT: pt_txisr(): Invalid tstate (%d) for chan %s.\n", lp->tstate, (cmd & CHANA? "A": "B") );
		pt_rts(lp, OFF);
		lp->tstate = IDLE;
		break;
    } 				/*switch */
    restore_flags(flags);
}

static void pt_rxisr(struct device *dev)
{
    struct pt_local *lp = (struct pt_local*) dev->priv;
    int cmd = lp->base + CTL;
    int bytecount;
    unsigned long flags;
    char rse;
    struct sk_buff *skb;
    int sksize, pkt_len;
    struct mbuf *cur_buf = NULL;
    unsigned char *cfix;

    save_flags(flags);
    cli();

    /* Get status byte from R1 */
    rse = rdscc(lp->cardbase, cmd, R1);

#ifdef PT_DEBUG
    printk(KERN_DEBUG "PT: pt_rxisr(): R1 = %#3x. (%d)\n", rse, lp->base & CHANA);
#endif

	if (lp->dmachan && (rse & Rx_OVR))
		lp->rstate = RXERROR;

    if (rdscc(lp->cardbase, cmd, R0) & Rx_CH_AV && !lp->dmachan)
    {
        /* There is a char to be stored
         * Read special condition bits before reading the data char
         */
        if (rse & Rx_OVR)
        {
             /* Rx overrun - toss buffer */
             /* wind back the pointers */
             lp->rcp = lp->rcvbuf->data;
             lp->rcvbuf->cnt = 0;
             lp->rstate = RXERROR;
             lp->stats.rx_errors++;
             lp->stats.rx_fifo_errors++;
         } else if (lp->rcvbuf->cnt >= lp->bufsiz)
             {
                 /* Too large packet
                  * wind back Rx buffer pointers
                  */
                 lp->rcp = lp->rcvbuf->data;
                 lp->rcvbuf->cnt = 0;
                 lp->rstate = TOOBIG;
             }
         /* ok, we can store the Rx char if no errors */
         if (lp->rstate == ACTIVE)
         {
             *lp->rcp++ = rdscc(lp->cardbase, cmd, R8);
             lp->rcvbuf->cnt++;
         } else {
             /* we got an error, dump the FIFO */
             (void) rdscc(lp->cardbase, cmd, R8);
             (void) rdscc(lp->cardbase, cmd, R8);
             (void) rdscc(lp->cardbase, cmd, R8);

             /* Reset error latch */
             wrtscc(lp->cardbase, cmd, R0, ERR_RES);
             lp->rstate = ACTIVE;

             /* Resync the SCC */
             wrtscc(lp->cardbase, cmd, R3, RxENABLE | ENT_HM | AUTO_ENAB | Rx8);

         }
     }

     if (rse & END_FR)
     {
#ifdef PT_DEBUG
	printk(KERN_DEBUG "PT: pt_rxisr() Got end of a %u byte frame.\n", lp->rcvbuf->cnt);
#endif
		if (lp->dmachan)
		{
			clear_dma_ff(lp->dmachan);
			bytecount = lp->bufsiz - get_dma_residue(lp->dmachan);
		} else {
			bytecount = lp->rcvbuf->cnt;
		}

         /* END OF FRAME - Make sure Rx was active */
         if (lp->rcvbuf->cnt > 0 || lp->dmachan)
         {
             if ((rse & CRC_ERR) || (lp->rstate > ACTIVE) || (bytecount < 10))
             {
                 if ((bytecount >= 10) && (rse & CRC_ERR))
                 {
                     lp->stats.rx_crc_errors++;
                 }
                 if (lp->dmachan)
                 {
                 	if (lp->rstate == RXERROR)
                 	{
                 		lp->stats.rx_errors++;
                 		lp->stats.rx_over_errors++;
                 	}
                 	lp->rstate = ACTIVE;
                 	setup_rx_dma(lp);
                 } else {
	                 /* wind back Rx buffer pointers */
    	             lp->rcp = lp->rcvbuf->data;
        	         lp->rcvbuf->cnt = 0;

					/* Re-sync the SCC */
					wrtscc(lp->cardbase, cmd, R3, RxENABLE | ENT_HM | AUTO_ENAB | Rx8);

        	     }
#ifdef PT_DEBUG
	printk(KERN_DEBUG "PT: pt_rxisr() %s error.\n", (rse & CRC_ERR)? "CRC" : "state");
#endif
             } else {