7990.c

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        int i, j;
        int status;
        DECLARE_LL;

        /* csr0 is 2f3 */
        WRITERDP(LE_C0_TINT | LE_C0_INEA);
        /* csr0 is 73 */

        j = lp->tx_old;
        for (i = j; i != lp->tx_new; i = j) {
                td = &ib->btx_ring [i];

                /* If we hit a packet not owned by us, stop */
                if (td->tmd1_bits & LE_T1_OWN)
                        break;
                
                if (td->tmd1_bits & LE_T1_ERR) {
                        status = td->misc;
            
                        lp->stats.tx_errors++;
                        if (status & LE_T3_RTY)  lp->stats.tx_aborted_errors++;
                        if (status & LE_T3_LCOL) lp->stats.tx_window_errors++;

                        if (status & LE_T3_CLOS) {
                                lp->stats.tx_carrier_errors++;
                                if (lp->auto_select) {
                                        lp->tpe = 1 - lp->tpe;
                                        printk("%s: Carrier Lost, trying %s\n",
                                               dev->name, lp->tpe?"TPE":"AUI");
                                        /* Stop the lance */
                                        WRITERAP(LE_CSR0);
                                        WRITERDP(LE_C0_STOP);
                                        lance_init_ring (dev);
                                        load_csrs (lp);
                                        init_restart_lance (lp);
                                        return 0;
                                }
                        }

                        /* buffer errors and underflows turn off the transmitter */
                        /* Restart the adapter */
                        if (status & (LE_T3_BUF|LE_T3_UFL)) {
                                lp->stats.tx_fifo_errors++;

                                printk ("%s: Tx: ERR_BUF|ERR_UFL, restarting\n",
                                        dev->name);
                                /* Stop the lance */
                                WRITERAP(LE_CSR0);
                                WRITERDP(LE_C0_STOP);
                                lance_init_ring (dev);
                                load_csrs (lp);
                                init_restart_lance (lp);
                                return 0;
                        }
                } else if ((td->tmd1_bits & LE_T1_POK) == LE_T1_POK) {
                        /*
                         * So we don't count the packet more than once.
                         */
                        td->tmd1_bits &= ~(LE_T1_POK);

                        /* One collision before packet was sent. */
                        if (td->tmd1_bits & LE_T1_EONE)
                                lp->stats.collisions++;

                        /* More than one collision, be optimistic. */
                        if (td->tmd1_bits & LE_T1_EMORE)
                                lp->stats.collisions += 2;

                        lp->stats.tx_packets++;
                }
        
                j = (j + 1) & lp->tx_ring_mod_mask;
        }
        lp->tx_old = j;
        WRITERDP(LE_C0_TINT | LE_C0_INEA);
        return 0;
}

static void lance_interrupt (int irq, void *dev_id, struct pt_regs *regs)
{
        struct net_device *dev = (struct net_device *)dev_id;
        struct lance_private *lp = (struct lance_private *)dev->priv;
        int csr0;
        DECLARE_LL;

	spin_lock (&lp->devlock);

        WRITERAP(LE_CSR0);              /* LANCE Controller Status */
        csr0 = READRDP();

        PRINT_RINGS();
        
        if (!(csr0 & LE_C0_INTR)) {     /* Check if any interrupt has */
		spin_lock (&lp->devlock);
                return;                 /* been generated by the Lance. */
	}

        /* Acknowledge all the interrupt sources ASAP */
        WRITERDP(csr0 & ~(LE_C0_INEA|LE_C0_TDMD|LE_C0_STOP|LE_C0_STRT|LE_C0_INIT));

        if ((csr0 & LE_C0_ERR)) {
                /* Clear the error condition */
                WRITERDP(LE_C0_BABL|LE_C0_ERR|LE_C0_MISS|LE_C0_INEA);
        }

        if (csr0 & LE_C0_RINT)
                lance_rx (dev);

        if (csr0 & LE_C0_TINT)
                lance_tx (dev);

        /* Log misc errors. */
        if (csr0 & LE_C0_BABL)
                lp->stats.tx_errors++;       /* Tx babble. */
        if (csr0 & LE_C0_MISS)
                lp->stats.rx_errors++;       /* Missed a Rx frame. */
        if (csr0 & LE_C0_MERR) {
                printk("%s: Bus master arbitration failure, status %4.4x.\n", 
                       dev->name, csr0);
                /* Restart the chip. */
                WRITERDP(LE_C0_STRT);
        }

        if (lp->tx_full && netif_queue_stopped(dev) && (TX_BUFFS_AVAIL >= 0)) {
		lp->tx_full = 0;
		netif_wake_queue (dev);
        }
        
        WRITERAP(LE_CSR0);
        WRITERDP(LE_C0_BABL|LE_C0_CERR|LE_C0_MISS|LE_C0_MERR|LE_C0_IDON|LE_C0_INEA);

	spin_unlock (&lp->devlock);
}

int lance_open (struct net_device *dev)
{
        struct lance_private *lp = (struct lance_private *)dev->priv;
	int res;
        DECLARE_LL;
        
        /* Install the Interrupt handler. Or we could shunt this out to specific drivers? */
        if (request_irq(lp->irq, lance_interrupt, 0, lp->name, dev))
                return -EAGAIN;

        res = lance_reset(dev);
	lp->devlock = SPIN_LOCK_UNLOCKED;
	netif_start_queue (dev);

	return res;
}

int lance_close (struct net_device *dev)
{
        struct lance_private *lp = (struct lance_private *) dev->priv;
        DECLARE_LL;
        
	netif_stop_queue (dev);

        /* Stop the LANCE */
        WRITERAP(LE_CSR0);
        WRITERDP(LE_C0_STOP);

        free_irq(lp->irq, dev);

        return 0;
}

void lance_tx_timeout(struct net_device *dev)
{
	printk("lance_tx_timeout\n");
	lance_reset(dev);
	dev->trans_start = jiffies;
	netif_start_queue (dev);
}


int lance_start_xmit (struct sk_buff *skb, struct net_device *dev)
{
        struct lance_private *lp = (struct lance_private *)dev->priv;
        volatile struct lance_init_block *ib = lp->init_block;
        int entry, skblen, len;
        static int outs;
	unsigned long flags;
        DECLARE_LL;

        if (!TX_BUFFS_AVAIL)
                return -1;

	netif_stop_queue (dev);

        skblen = skb->len;

#ifdef DEBUG_DRIVER
        /* dump the packet */
        {
                int i;
        
                for (i = 0; i < 64; i++) {
                        if ((i % 16) == 0)
                                printk ("\n");
                        printk ("%2.2x ", skb->data [i]);
                }
        }
#endif
        len = (skblen <= ETH_ZLEN) ? ETH_ZLEN : skblen;
        entry = lp->tx_new & lp->tx_ring_mod_mask;
        ib->btx_ring [entry].length = (-len) | 0xf000;
        ib->btx_ring [entry].misc = 0;
    
        memcpy ((char *)&ib->tx_buf [entry][0], skb->data, skblen);
    
        /* Now, give the packet to the lance */
        ib->btx_ring [entry].tmd1_bits = (LE_T1_POK|LE_T1_OWN);
        lp->tx_new = (lp->tx_new+1) & lp->tx_ring_mod_mask;

        outs++;
        /* Kick the lance: transmit now */
        WRITERDP(LE_C0_INEA | LE_C0_TDMD);
        dev->trans_start = jiffies;
        dev_kfree_skb (skb);
    
	spin_lock_irqsave (&lp->devlock, flags);
        if (TX_BUFFS_AVAIL)
		netif_start_queue (dev);
	else
		lp->tx_full = 1;
	spin_unlock_irqrestore (&lp->devlock, flags);

        return 0;
}

struct net_device_stats *lance_get_stats (struct net_device *dev)
{
        struct lance_private *lp = (struct lance_private *) dev->priv;

        return &lp->stats;
}

/* taken from the depca driver via a2065.c */
static void lance_load_multicast (struct net_device *dev)
{
        struct lance_private *lp = (struct lance_private *) dev->priv;
        volatile struct lance_init_block *ib = lp->init_block;
        volatile u16 *mcast_table = (u16 *)&ib->filter;
        struct dev_mc_list *dmi=dev->mc_list;
        char *addrs;
        int i, j, bit, byte;
        u32 crc, poly = CRC_POLYNOMIAL_LE;
        
        /* set all multicast bits */
        if (dev->flags & IFF_ALLMULTI){ 
                ib->filter [0] = 0xffffffff;
                ib->filter [1] = 0xffffffff;
                return;
        }
        /* clear the multicast filter */
        ib->filter [0] = 0;
        ib->filter [1] = 0;

        /* Add addresses */
        for (i = 0; i < dev->mc_count; i++){
                addrs = dmi->dmi_addr;
                dmi   = dmi->next;

                /* multicast address? */
                if (!(*addrs & 1))
                        continue;
                
                crc = 0xffffffff;
                for (byte = 0; byte < 6; byte++)
                        for (bit = *addrs++, j = 0; j < 8; j++, bit>>=1)
                        {
                                int test;

                                test = ((bit ^ crc) & 0x01);
                                crc >>= 1;

                                if (test)
                                {
                                        crc = crc ^ poly;
                                }
                        }
                
                crc = crc >> 26;
                mcast_table [crc >> 4] |= 1 << (crc & 0xf);
        }
        return;
}


void lance_set_multicast (struct net_device *dev)
{
        struct lance_private *lp = (struct lance_private *) dev->priv;
        volatile struct lance_init_block *ib = lp->init_block;
	int stopped;
        DECLARE_LL;

	stopped = netif_queue_stopped(dev);
	if (!stopped)
		netif_stop_queue (dev);

        while (lp->tx_old != lp->tx_new)
                schedule();

        WRITERAP(LE_CSR0);
        WRITERDP(LE_C0_STOP);
        lance_init_ring (dev);

        if (dev->flags & IFF_PROMISC) {
                ib->mode |= LE_MO_PROM;
        } else {
                ib->mode &= ~LE_MO_PROM;
                lance_load_multicast (dev);
        }
        load_csrs (lp);
        init_restart_lance (lp);

	if (!stopped)
		netif_start_queue (dev);
}