via-rhine.c

GNU Mach 微内核源代码, 基于美国卡内基美隆大学的 Mach 研究项目

			   dev->name, np->cur_tx, entry);
	}
	return 0;
}

/* The interrupt handler does all of the Rx thread work and cleans up
   after the Tx thread. */
static void intr_handler(int irq, void *dev_instance, struct pt_regs *rgs)
{
	struct device *dev = (struct device *)dev_instance;
	struct netdev_private *np;
	long ioaddr, boguscnt = max_interrupt_work;

	ioaddr = dev->base_addr;
	np = (struct netdev_private *)dev->priv;
#if defined(__i386__)
	/* A lock to prevent simultaneous entry bug on Intel SMP machines. */
	if (test_and_set_bit(0, (void*)&dev->interrupt)) {
		printk(KERN_ERR"%s: SMP simultaneous entry of an interrupt handler.\n",
			   dev->name);
		dev->interrupt = 0;	/* Avoid halting machine. */
		return;
	}
#else
	if (dev->interrupt) {
		printk(KERN_ERR "%s: Re-entering the interrupt handler.\n", dev->name);
		return;
	}
	dev->interrupt = 1;
#endif

	do {
		u32 intr_status = readw(ioaddr + IntrStatus);

		/* Acknowledge all of the current interrupt sources ASAP. */
		writew(intr_status & 0xffff, ioaddr + IntrStatus);

		if (debug > 4)
			printk(KERN_DEBUG "%s: Interrupt, status %4.4x.\n",
				   dev->name, intr_status);

		if (intr_status == 0)
			break;

		if (intr_status & (IntrRxDone | IntrRxErr | IntrRxDropped |
						   IntrRxWakeUp | IntrRxEmpty | IntrRxNoBuf))
			netdev_rx(dev);

		for (; np->cur_tx - np->dirty_tx > 0; np->dirty_tx++) {
			int entry = np->dirty_tx % TX_RING_SIZE;
			int txstatus;
			if (np->tx_ring[entry].tx_own)
				break;
			txstatus = np->tx_ring[entry].tx_status;
			if (debug > 6)
				printk(KERN_DEBUG " Tx scavenge %d status %4.4x.\n",
					   entry, txstatus);
			if (txstatus & 0x8000) {
				if (debug > 1)
					printk(KERN_DEBUG "%s: Transmit error, Tx status %4.4x.\n",
						   dev->name, txstatus);
				np->stats.tx_errors++;
				if (txstatus & 0x0400) np->stats.tx_carrier_errors++;
				if (txstatus & 0x0200) np->stats.tx_window_errors++;
				if (txstatus & 0x0100) np->stats.tx_aborted_errors++;
				if (txstatus & 0x0080) np->stats.tx_heartbeat_errors++;
				if (txstatus & 0x0002) np->stats.tx_fifo_errors++;
#ifdef ETHER_STATS
				if (txstatus & 0x0100) np->stats.collisions16++;
#endif
				/* Transmitter restarted in 'abnormal' handler. */
			} else {
#ifdef ETHER_STATS
				if (txstatus & 0x0001) np->stats.tx_deferred++;
#endif
				np->stats.collisions += (txstatus >> 3) & 15;
#if defined(NETSTATS_VER2)
				np->stats.tx_bytes += np->tx_ring[entry].desc_length & 0x7ff;
#endif
				np->stats.tx_packets++;
			}
			/* Free the original skb. */
			dev_free_skb(np->tx_skbuff[entry]);
			np->tx_skbuff[entry] = 0;
		}
		if (np->tx_full && dev->tbusy
			&& np->cur_tx - np->dirty_tx < TX_RING_SIZE - 4) {
			/* The ring is no longer full, clear tbusy. */
			np->tx_full = 0;
			clear_bit(0, (void*)&dev->tbusy);
			mark_bh(NET_BH);
		}

		/* Abnormal error summary/uncommon events handlers. */
		if (intr_status & (IntrPCIErr | IntrLinkChange | IntrMIIChange |
						   IntrStatsMax | IntrTxAbort | IntrTxUnderrun))
			netdev_error(dev, intr_status);

		if (--boguscnt < 0) {
			printk(KERN_WARNING "%s: Too much work at interrupt, "
				   "status=0x%4.4x.\n",
				   dev->name, intr_status);
			break;
		}
	} while (1);

	if (debug > 3)
		printk(KERN_DEBUG "%s: exiting interrupt, status=%#4.4x.\n",
			   dev->name, readw(ioaddr + IntrStatus));

#if defined(__i386__)
	clear_bit(0, (void*)&dev->interrupt);
#else
	dev->interrupt = 0;
#endif
	return;
}

/* This routine is logically part of the interrupt handler, but isolated
   for clarity and better register allocation. */
static int netdev_rx(struct device *dev)
{
	struct netdev_private *np = (struct netdev_private *)dev->priv;
	int entry = np->cur_rx % RX_RING_SIZE;
	int boguscnt = np->dirty_rx + RX_RING_SIZE - np->cur_rx;

	if (debug > 4) {
		printk(KERN_DEBUG " In netdev_rx(), entry %d status %4.4x.\n",
			   entry, np->rx_head_desc->rx_length);
	}

	/* If EOP is set on the next entry, it's a new packet. Send it up. */
	while ( ! (np->rx_head_desc->rx_length & DescOwn)) {
		struct rx_desc *desc = np->rx_head_desc;
		int data_size = desc->rx_length;
		u16 desc_status = desc->rx_status;

		if (debug > 4)
			printk(KERN_DEBUG "  netdev_rx() status is %4.4x.\n",
				   desc_status);
		if (--boguscnt < 0)
			break;
		if ( (desc_status & (RxWholePkt | RxErr)) !=  RxWholePkt) {
			if ((desc_status & RxWholePkt) !=  RxWholePkt) {
				printk(KERN_WARNING "%s: Oversized Ethernet frame spanned "
					   "multiple buffers, entry %#x length %d status %4.4x!\n",
					   dev->name, np->cur_rx, data_size, desc_status);
				printk(KERN_WARNING "%s: Oversized Ethernet frame %p vs %p.\n",
					   dev->name, np->rx_head_desc,
					   &np->rx_ring[np->cur_rx % RX_RING_SIZE]);
				np->stats.rx_length_errors++;
			} else if (desc_status & RxErr) {
				/* There was a error. */
				if (debug > 2)
					printk(KERN_DEBUG "  netdev_rx() Rx error was %8.8x.\n",
						   desc_status);
				np->stats.rx_errors++;
				if (desc_status & 0x0030) np->stats.rx_length_errors++;
				if (desc_status & 0x0048) np->stats.rx_fifo_errors++;
				if (desc_status & 0x0004) np->stats.rx_frame_errors++;
				if (desc_status & 0x0002) np->stats.rx_crc_errors++;
			}
		} else {
			struct sk_buff *skb;
			/* Length should omit the CRC */
			u16 pkt_len = data_size - 4;

			/* Check if the packet is long enough to accept without copying
			   to a minimally-sized skbuff. */
			if (pkt_len < rx_copybreak
				&& (skb = dev_alloc_skb(pkt_len + 2)) != NULL) {
				skb->dev = dev;
				skb_reserve(skb, 2);	/* 16 byte align the IP header */
#if ! defined(__alpha__) || USE_IP_COPYSUM		/* Avoid misaligned on Alpha */
				eth_copy_and_sum(skb, bus_to_virt(desc->addr),
								 pkt_len, 0);
				skb_put(skb, pkt_len);
#else
				memcpy(skb_put(skb,pkt_len), bus_to_virt(desc->addr), pkt_len);
#endif
			} else {
				skb_put(skb = np->rx_skbuff[entry], pkt_len);
				np->rx_skbuff[entry] = NULL;
			}
			skb->protocol = eth_type_trans(skb, dev);
			netif_rx(skb);
			dev->last_rx = jiffies;
			np->stats.rx_packets++;
		}
		entry = (++np->cur_rx) % RX_RING_SIZE;
		np->rx_head_desc = &np->rx_ring[entry];
	}

	/* Refill the Rx ring buffers. */
	for (; np->cur_rx - np->dirty_rx > 0; np->dirty_rx++) {
		struct sk_buff *skb;
		entry = np->dirty_rx % RX_RING_SIZE;
		if (np->rx_skbuff[entry] == NULL) {
			skb = dev_alloc_skb(np->rx_buf_sz);
			np->rx_skbuff[entry] = skb;
			if (skb == NULL)
				break;			/* Better luck next round. */
			skb->dev = dev;			/* Mark as being used by this device. */
			np->rx_ring[entry].addr = virt_to_bus(skb->tail);
		}
		np->rx_ring[entry].rx_status = 0;
		np->rx_ring[entry].rx_length = DescOwn;
	}

	/* Pre-emptively restart Rx engine. */
	writew(CmdRxDemand | np->chip_cmd, dev->base_addr + ChipCmd);
	return 0;
}

static void netdev_error(struct device *dev, int intr_status)
{
	struct netdev_private *np = (struct netdev_private *)dev->priv;
	long ioaddr = dev->base_addr;

	if (intr_status & (IntrMIIChange | IntrLinkChange)) {
		if (readb(ioaddr + MIIStatus) & 0x02)
			/* Link failed, restart autonegotiation. */
			mdio_write(dev, np->phys[0], 0, 0x3300);
		else
			check_duplex(dev);
		if (debug)
			printk(KERN_ERR "%s: MII status changed: Autonegotiation "
				   "advertising %4.4x  partner %4.4x.\n", dev->name,
			   mdio_read(dev, np->phys[0], 4),
			   mdio_read(dev, np->phys[0], 5));
	}
	if (intr_status & IntrStatsMax) {
		np->stats.rx_crc_errors	+= readw(ioaddr + RxCRCErrs);
		np->stats.rx_missed_errors	+= readw(ioaddr + RxMissed);
		writel(0, RxMissed);
	}
	if (intr_status & IntrTxAbort) {
		/* Stats counted in Tx-done handler, just restart Tx. */
		writew(CmdTxDemand | np->chip_cmd, dev->base_addr + ChipCmd);
	}
	if (intr_status & IntrTxUnderrun) {
		if (np->tx_thresh < 0xE0)
			writeb(np->tx_thresh += 0x20, ioaddr + TxConfig);
		if (debug > 1)
			printk(KERN_INFO "%s: Transmitter underrun, increasing Tx "
				   "threshold setting to %2.2x.\n", dev->name, np->tx_thresh);
	}
	if ((intr_status & ~(IntrLinkChange|IntrStatsMax|IntrTxAbort)) && debug) {
		printk(KERN_ERR "%s: Something Wicked happened! %4.4x.\n",
			   dev->name, intr_status);
		/* Recovery for other fault sources not known. */
		writew(CmdTxDemand | np->chip_cmd, dev->base_addr + ChipCmd);
	}
}

static struct enet_statistics *get_stats(struct device *dev)
{
	struct netdev_private *np = (struct netdev_private *)dev->priv;
	long ioaddr = dev->base_addr;

	/* Nominally we should lock this segment of code for SMP, although
	   the vulnerability window is very small and statistics are
	   non-critical. */
	np->stats.rx_crc_errors	+= readw(ioaddr + RxCRCErrs);
	np->stats.rx_missed_errors	+= readw(ioaddr + RxMissed);
	writel(0, RxMissed);

	return &np->stats;
}

/* The big-endian AUTODIN II ethernet CRC calculation.
   N.B. Do not use for bulk data, use a table-based routine instead.
   This is common code and should be moved to net/core/crc.c */
static unsigned const ethernet_polynomial = 0x04c11db7U;
static inline u32 ether_crc(int length, unsigned char *data)
{
    int crc = -1;

    while(--length >= 0) {
		unsigned char current_octet = *data++;
		int bit;
		for (bit = 0; bit < 8; bit++, current_octet >>= 1) {
			crc = (crc << 1) ^
				((crc < 0) ^ (current_octet & 1) ? ethernet_polynomial : 0);
		}
    }
    return crc;
}

static void set_rx_mode(struct device *dev)
{
	struct netdev_private *np = (struct netdev_private *)dev->priv;
	long ioaddr = dev->base_addr;
	u32 mc_filter[2];			/* Multicast hash filter */
	u8 rx_mode;					/* Note: 0x02=accept runt, 0x01=accept errs */

	if (dev->flags & IFF_PROMISC) {			/* Set promiscuous. */
		/* Unconditionally log net taps. */
		printk(KERN_NOTICE "%s: Promiscuous mode enabled.\n", dev->name);
		rx_mode = 0x1C;
	} else if ((dev->mc_count > multicast_filter_limit)
			   ||  (dev->flags & IFF_ALLMULTI)) {
		/* Too many to match, or accept all multicasts. */
		rx_mode = 0x0C;
	} else {
		struct dev_mc_list *mclist;
		int i;
		memset(mc_filter, 0, sizeof(mc_filter));
		for (i = 0, mclist = dev->mc_list; mclist && i < dev->mc_count;
			 i++, mclist = mclist->next) {
			set_bit(ether_crc(ETH_ALEN, mclist->dmi_addr) >> 26,
					mc_filter);
		}
		writel(mc_filter[0], ioaddr + MulticastFilter0);
		writel(mc_filter[1], ioaddr + MulticastFilter1);
		rx_mode = 0x0C;
	}
	writeb(np->rx_thresh | rx_mode, ioaddr + RxConfig);
}

static int mii_ioctl(struct device *dev, struct ifreq *rq, int cmd)
{
	u16 *data = (u16 *)&rq->ifr_data;

	switch(cmd) {
	case SIOCDEVPRIVATE:		/* Get the address of the PHY in use. */
		data[0] = ((struct netdev_private *)dev->priv)->phys[0] & 0x1f;
		/* Fall Through */
	case SIOCDEVPRIVATE+1:		/* Read the specified MII register. */
		data[3] = mdio_read(dev, data[0] & 0x1f, data[1] & 0x1f);
		return 0;
	case SIOCDEVPRIVATE+2:		/* Write the specified MII register */
		if (!suser())
			return -EPERM;
		mdio_write(dev, data[0] & 0x1f, data[1] & 0x1f, data[2]);
		return 0;
	default:
		return -EOPNOTSUPP;
	}
}

static int netdev_close(struct device *dev)
{
	long ioaddr = dev->base_addr;
	struct netdev_private *np = (struct netdev_private *)dev->priv;
	int i;

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

	if (debug > 1)
		printk(KERN_DEBUG "%s: Shutting down ethercard, status was %4.4x.\n",
			   dev->name, readw(ioaddr + ChipCmd));

	/* Disable interrupts by clearing the interrupt mask. */
	writew(0x0000, ioaddr + IntrEnable);

	/* Stop the chip's Tx and Rx processes. */
	writew(CmdStop, ioaddr + ChipCmd);

	del_timer(&np->timer);

	free_irq(dev->irq, dev);

	/* Free all the skbuffs in the Rx queue. */
	for (i = 0; i < RX_RING_SIZE; i++) {
		np->rx_ring[i].rx_length = 0;
		np->rx_ring[i].addr = 0xBADF00D0; /* An invalid address. */
		if (np->rx_skbuff[i]) {
#if LINUX_VERSION_CODE < 0x20100
			np->rx_skbuff[i]->free = 1;
#endif
			dev_free_skb(np->rx_skbuff[i]);
		}
		np->rx_skbuff[i] = 0;
	}
	for (i = 0; i < TX_RING_SIZE; i++) {
		if (np->tx_skbuff[i])
			dev_free_skb(np->tx_skbuff[i]);
		np->tx_skbuff[i] = 0;
	}

	MOD_DEC_USE_COUNT;

	return 0;
}


#ifdef MODULE
int init_module(void)
{
	if (debug)					/* Emit version even if no cards detected. */
		printk(KERN_INFO "%s" KERN_INFO "%s", versionA, versionB);
#ifdef CARDBUS
	register_driver(&etherdev_ops);
	return 0;
#else
	return pci_etherdev_probe(NULL, pci_tbl);
#endif
}

void cleanup_module(void)
{

#ifdef CARDBUS
	unregister_driver(&etherdev_ops);
#endif

	/* No need to check MOD_IN_USE, as sys_delete_module() checks. */
	while (root_net_dev) {
		struct netdev_private *np =
			(struct netdev_private *)(root_net_dev->priv);
		unregister_netdev(root_net_dev);
#ifdef VIA_USE_IO
		release_region(root_net_dev->base_addr, pci_tbl[np->chip_id].io_size);
#else
		iounmap((char *)(root_net_dev->base_addr));
#endif
		kfree(root_net_dev);
		root_net_dev = np->next_module;
#if 0
		kfree(np);				/* Assumption: no struct realignment. */
#endif
	}
}

#endif  /* MODULE */

/*
 * Local variables:
 *  compile-command: "gcc -DMODULE -D__KERNEL__ -I/usr/src/linux/net/inet -Wall -Wstrict-prototypes -O6 -c via-rhine.c `[ -f /usr/include/linux/modversions.h ] && echo -DMODVERSIONS`"
 *  SMP-compile-command: "gcc -D__SMP__ -DMODULE -D__KERNEL__ -I/usr/src/linux/net/inet -Wall -Wstrict-prototypes -O6 -c via-rhine.c `[ -f /usr/include/linux/modversions.h ] && echo -DMODVERSIONS`"
 *  c-indent-level: 4
 *  c-basic-offset: 4
 *  tab-width: 4
 * End:
 */