lmc_main.c

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

        if(stat & 0x00000004){ /* Catch a CRC error by the Xilinx */
            sc->stats.rx_errors++;
            sc->stats.rx_crc_errors++;
            goto skip_packet;
        }


        if (len > LMC_PKT_BUF_SZ){
            sc->stats.rx_length_errors++;
            localLengthErrCnt++;
            goto skip_packet;
        }

        if (len < sc->lmc_crcSize + 2) {
            sc->stats.rx_length_errors++;
            sc->stats.rx_SmallPktCnt++;
            localLengthErrCnt++;
            goto skip_packet;
        }

        if(stat & 0x00004000){
            printk(KERN_WARNING "%s: Receiver descriptor error, receiver out of sync?\n", dev->name);
        }

        len -= sc->lmc_crcSize;

        skb = sc->lmc_rxq[i];

        /*
         * We ran out of memory at some point
         * just allocate an skb buff and continue.
         */
        
        if(skb == 0x0){
            nsb = dev_alloc_skb (LMC_PKT_BUF_SZ + 2);
            if (nsb) {
                LMC_SKB_FREE(nsb, 1);
                sc->lmc_rxq[i] = nsb;
                nsb->dev = dev;
                sc->lmc_rxring[i].buffer1 = virt_to_bus (nsb->tail);
            }
            sc->failed_recv_alloc = 1;
            goto skip_packet;
        }
        
        dev->last_rx = jiffies;
        sc->stats.rx_packets++;
        sc->stats.rx_bytes += len;

        LMC_CONSOLE_LOG("recv", skb->data, len);

        /*
         * I'm not sure of the sanity of this
         * Packets could be arriving at a constant
         * 44.210mbits/sec and we're going to copy
         * them into a new buffer??
         */
        
        if(len > (LMC_MTU - (LMC_MTU>>2))){ /* len > LMC_MTU * 0.75 */
            /*
             * If it's a large packet don't copy it just hand it up
             */
        give_it_anyways:

            sc->lmc_rxq[i] = 0x0;
            sc->lmc_rxring[i].buffer1 = 0x0;

            skb_put (skb, len);
            skb->protocol = lmc_proto_type(sc, skb);
            skb->protocol = htons(ETH_P_WAN_PPP);
            skb->mac.raw = skb->data;
//            skb->nh.raw = skb->data;
            skb->dev = dev;
            lmc_proto_netif(sc, skb);

            /*
             * This skb will be destroyed by the upper layers, make a new one
             */
            nsb = dev_alloc_skb (LMC_PKT_BUF_SZ + 2);
            if (nsb) {
                LMC_SKB_FREE(nsb, 1);
                sc->lmc_rxq[i] = nsb;
                nsb->dev = dev;
                sc->lmc_rxring[i].buffer1 = virt_to_bus (nsb->tail);
                /* Transferred to 21140 below */
            }
            else {
                /*
                 * We've run out of memory, stop trying to allocate
                 * memory and exit the interrupt handler
                 *
                 * The chip may run out of receivers and stop
                 * in which care we'll try to allocate the buffer
                 * again.  (once a second)
                 */
                sc->stats.rx_BuffAllocErr++;
                LMC_EVENT_LOG(LMC_EVENT_RCVINT, stat, len);
                sc->failed_recv_alloc = 1;
                goto skip_out_of_mem;
            }
        }
        else {
            nsb = dev_alloc_skb(len);
            if(!nsb) {
                goto give_it_anyways;
            }
            memcpy(skb_put(nsb, len), skb->data, len);
            
            nsb->protocol = lmc_proto_type(sc, skb);
            nsb->mac.raw = nsb->data;
//            nsb->nh.raw = nsb->data;
            nsb->dev = dev;
            lmc_proto_netif(sc, nsb);
        }

    skip_packet:
        LMC_EVENT_LOG(LMC_EVENT_RCVINT, stat, len);
        sc->lmc_rxring[i].status = DESC_OWNED_BY_DC21X4;

        sc->lmc_next_rx++;
        i = sc->lmc_next_rx % LMC_RXDESCS;
        rx_work_limit--;
        if (rx_work_limit < 0)
            break;
    }

    /* detect condition for LMC1000 where DSU cable attaches and fills
     * descriptors with bogus packets
     *
    if (localLengthErrCnt > LMC_RXDESCS - 3) {
        sc->stats.rx_BadPktSurgeCnt++;
        LMC_EVENT_LOG(LMC_EVENT_BADPKTSURGE,
                      localLengthErrCnt,
                      sc->stats.rx_BadPktSurgeCnt);
    } */

    /* save max count of receive descriptors serviced */
    if (rxIntLoopCnt > sc->stats.rxIntLoopCnt) {
        sc->stats.rxIntLoopCnt = rxIntLoopCnt;	/* debug -baz */
    }

#ifdef DEBUG
    if (rxIntLoopCnt == 0)
    {
        for (i = 0; i < LMC_RXDESCS; i++)
        {
            if ((sc->lmc_rxring[i].status & LMC_RDES_OWN_BIT)
                != DESC_OWNED_BY_DC21X4)
            {
                rxIntLoopCnt++;
            }
        }
        LMC_EVENT_LOG(LMC_EVENT_RCVEND, rxIntLoopCnt, 0);
    }
#endif


    lmc_led_off(sc, LMC_DS3_LED3);

skip_out_of_mem:

    lmc_trace(dev, "lmc_rx out");

    return 0;
}

static struct net_device_stats *lmc_get_stats (struct net_device *dev) /*fold00*/
{
    lmc_softc_t *sc;
    LMC_SPIN_FLAGS;

    lmc_trace(dev, "lmc_get_stats in");

    sc = dev->priv;

    spin_lock_irqsave(&sc->lmc_lock, flags);

    sc->stats.rx_missed_errors += LMC_CSR_READ (sc, csr_missed_frames) & 0xffff;

    spin_unlock_irqrestore(&sc->lmc_lock, flags);

    lmc_trace(dev, "lmc_get_stats out");

    return (struct net_device_stats *) &sc->stats;
}

#ifdef MODULE

int init_module (void) /*fold00*/
{
    printk ("lmc: module loaded\n");

    /* Have lmc_probe search for all the cards, and allocate devices */
    if (lmc_probe (NULL) < 0)
        return -EIO;

    return 0;
}

void cleanup_module (void) /*fold00*/
{
    struct net_device *dev, *next;
    lmc_softc_t *sc;

    /* we have no pointer to our devices, since they are all dynamically
     * allocated.  So, here we loop through all the network devices
     * looking for ours.  When found, dispose of them properly.
     */

    for (dev = Lmc_root_dev;
         dev != NULL;
         dev = next )
    {

        next = ((lmc_softc_t *) dev->priv)->next_module; /* get it now before we deallocate it */
        printk ("%s: removing...\n", dev->name);

        /* close the syncppp stuff, and release irq. Close is run on unreg net */
        lmc_close (dev);
	sc = dev->priv;
        if (sc != NULL)
            lmc_proto_detach(sc);

        /* Remove the device from the linked list */
        unregister_netdev (dev);

        /* Let go of the io region */;
        release_region (dev->base_addr, LMC_REG_RANGE);

        /* free our allocated structures. */
        kfree (dev->priv);
        dev->priv = NULL;

        kfree ((struct ppp_device *) dev);
        dev = NULL;
    }


    Lmc_root_dev = NULL;
    printk ("lmc module unloaded\n");
}
#endif

unsigned lmc_mii_readreg (lmc_softc_t * const sc, unsigned devaddr, unsigned regno) /*fold00*/
{
    int i;
    int command = (0xf6 << 10) | (devaddr << 5) | regno;
    int retval = 0;

    lmc_trace(sc->lmc_device, "lmc_mii_readreg in");

    LMC_MII_SYNC (sc);

    lmc_trace(sc->lmc_device, "lmc_mii_readreg: done sync");

    for (i = 15; i >= 0; i--)
    {
        int dataval = (command & (1 << i)) ? 0x20000 : 0;

        LMC_CSR_WRITE (sc, csr_9, dataval);
        lmc_delay ();
        /* __SLOW_DOWN_IO; */
        LMC_CSR_WRITE (sc, csr_9, dataval | 0x10000);
        lmc_delay ();
        /* __SLOW_DOWN_IO; */
    }

    lmc_trace(sc->lmc_device, "lmc_mii_readreg: done1");

    for (i = 19; i > 0; i--)
    {
        LMC_CSR_WRITE (sc, csr_9, 0x40000);
        lmc_delay ();
        /* __SLOW_DOWN_IO; */
        retval = (retval << 1) | ((LMC_CSR_READ (sc, csr_9) & 0x80000) ? 1 : 0);
        LMC_CSR_WRITE (sc, csr_9, 0x40000 | 0x10000);
        lmc_delay ();
        /* __SLOW_DOWN_IO; */
    }

    lmc_trace(sc->lmc_device, "lmc_mii_readreg out");

    return (retval >> 1) & 0xffff;
}

void lmc_mii_writereg (lmc_softc_t * const sc, unsigned devaddr, unsigned regno, unsigned data) /*fold00*/
{
    int i = 32;
    int command = (0x5002 << 16) | (devaddr << 23) | (regno << 18) | data;

    lmc_trace(sc->lmc_device, "lmc_mii_writereg in");

    LMC_MII_SYNC (sc);

    i = 31;
    while (i >= 0)
    {
        int datav;

        if (command & (1 << i))
            datav = 0x20000;
        else
            datav = 0x00000;

        LMC_CSR_WRITE (sc, csr_9, datav);
        lmc_delay ();
        /* __SLOW_DOWN_IO; */
        LMC_CSR_WRITE (sc, csr_9, (datav | 0x10000));
        lmc_delay ();
        /* __SLOW_DOWN_IO; */
        i--;
    }

    i = 2;
    while (i > 0)
    {
        LMC_CSR_WRITE (sc, csr_9, 0x40000);
        lmc_delay ();
        /* __SLOW_DOWN_IO; */
        LMC_CSR_WRITE (sc, csr_9, 0x50000);
        lmc_delay ();
        /* __SLOW_DOWN_IO; */
        i--;
    }

    lmc_trace(sc->lmc_device, "lmc_mii_writereg out");
}

static void lmc_softreset (lmc_softc_t * const sc) /*fold00*/
{
    int i;

    lmc_trace(sc->lmc_device, "lmc_softreset in");

    /* Initialize the receive rings and buffers. */
    sc->lmc_txfull = 0;
    sc->lmc_next_rx = 0;
    sc->lmc_next_tx = 0;
    sc->lmc_taint_rx = 0;
    sc->lmc_taint_tx = 0;

    /*
     * Setup each one of the receiver buffers
     * allocate an skbuff for each one, setup the descriptor table
     * and point each buffer at the next one
     */

    for (i = 0; i < LMC_RXDESCS; i++)
    {
        struct sk_buff *skb;

        if (sc->lmc_rxq[i] == NULL)
        {
            skb = dev_alloc_skb (LMC_PKT_BUF_SZ + 2);
            if(skb == NULL){
                printk(KERN_WARNING "%s: Failed to allocate receiver ring, will try again\n", sc->name);
                sc->failed_ring = 1;
                break;
            }
            else{
                sc->lmc_rxq[i] = skb;
            }
        }
        else
        {
            skb = sc->lmc_rxq[i];
        }

        skb->dev = sc->lmc_device;
        LMC_SKB_FREE(skb, 1);

        /* owned by 21140 */
        sc->lmc_rxring[i].status = 0x80000000;

        /* used to be PKT_BUF_SZ now uses skb since we loose some to head room */
        sc->lmc_rxring[i].length = skb->end - skb->data;

        /* use to be tail which is dumb since you're thinking why write
         * to the end of the packj,et but since there's nothing there tail == data
         */
        sc->lmc_rxring[i].buffer1 = virt_to_bus (skb->data);

        /* This is fair since the structure is static and we have the next address */
        sc->lmc_rxring[i].buffer2 = virt_to_bus (&sc->lmc_rxring[i + 1]);

    }

    /*
     * Sets end of ring
     */
    sc->lmc_rxring[i - 1].length |= 0x02000000; /* Set end of buffers flag */
    sc->lmc_rxring[i - 1].buffer2 = virt_to_bus (&sc->lmc_rxring[0]); /* Point back to the start */
    LMC_CSR_WRITE (sc, csr_rxlist, virt_to_bus (sc->lmc_rxring)); /* write base address */


    /* Initialize the transmit rings and buffers */
    for (i = 0; i < LMC_TXDESCS; i++)
    {
        if (sc->lmc_txq[i] != NULL){		/* have buffer */
            dev_kfree_skb(sc->lmc_txq[i]);	/* free it */
            sc->stats.tx_dropped++;      /* We just dropped a packet */
        }
        sc->lmc_txq[i] = 0;
        sc->lmc_txring[i].status = 0x00000000;
        sc->lmc_txring[i].buffer2 = virt_to_bus (&sc->lmc_txring[i + 1]);
    }
    sc->lmc_txring[i - 1].buffer2 = virt_to_bus (&sc->lmc_txring[0]);
    LMC_CSR_WRITE (sc, csr_txlist, virt_to_bus (sc->lmc_txring));

    lmc_trace(sc->lmc_device, "lmc_softreset out");
}

static int lmc_set_config(struct net_device *dev, struct ifmap *map) /*fold00*/
{
    lmc_trace(dev, "lmc_set_config in");
    lmc_trace(dev, "lmc_set_config out");
    return -EOPNOTSUPP;
}

void lmc_gpio_mkinput(lmc_softc_t * const sc, u_int32_t bits) /*fold00*/
{
    lmc_trace(sc->lmc_device, "lmc_gpio_mkinput in");
    sc->lmc_gpio_io &= ~bits;
    LMC_CSR_WRITE(sc, csr_gp, TULIP_GP_PINSET | (sc->lmc_gpio_io));
    lmc_trace(sc->lmc_device, "lmc_gpio_mkinput out");
}

void lmc_gpio_mkoutput(lmc_softc_t * const sc, u_int32_t bits) /*fold00*/
{
    lmc_trace(sc->lmc_device, "lmc_gpio_mkoutput in");
    sc->lmc_gpio_io |= bits;
    LMC_CSR_WRITE(sc, csr_gp, TULIP_GP_PINSET | (sc->lmc_gpio_io));
    lmc_trace(sc->lmc_device, "lmc_gpio_mkoutput out");
}

void lmc_led_on(lmc_softc_t * const sc, u_int32_t led) /*fold00*/
{
    lmc_trace(sc->lmc_device, "lmc_led_on in");
    if((~sc->lmc_miireg16) & led){ /* Already on! */
        lmc_trace(sc->lmc_device, "lmc_led_on aon out");
        return;
    }
    
    sc->lmc_miireg16 &= ~led;
    lmc_mii