skeleton.c

powerpc内核mpc8241linux系统下net驱动程序

	 */
	if (request_irq(dev->irq, &net_interrupt, 0, cardname, dev)) {
		return -EAGAIN;
	}
	/*
	 * Always allocate the DMA channel after the IRQ,
	 * and clean up on failure.
	 */
	if (request_dma(dev->dma, cardname)) {
		free_irq(dev->irq, dev);
		return -EAGAIN;
	}

	/* Reset the hardware here. Don't forget to set the station address. */
	/*chipset_init(dev, 1);*/
	outb(0x00, ioaddr);
	lp->open_time = jiffies;

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

	MOD_INC_USE_COUNT;

	return 0;
}

static int net_send_packet(struct sk_buff *skb, struct device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	int ioaddr = dev->base_addr;

	if (dev->tbusy) {
		/*
		 * If we get here, some higher level has decided we are broken.
		 * There should really be a "kick me" function call instead.
		 */
		int tickssofar = jiffies - dev->trans_start;
		if (tickssofar < 5)
			return 1;
		printk(KERN_WARNING "%s: transmit timed out, %s?\n", dev->name,
			   tx_done(dev) ? "IRQ conflict" : "network cable problem");
		/* Try to restart the adaptor. */
		chipset_init(dev, 1);
		dev->tbusy=0;
		dev->trans_start = jiffies;
	}

	/*
	 * Block a timer-based transmit from overlapping. This could better be
	 * done with atomic_swap(1, dev->tbusy), but set_bit() works as well.
	 */
	if (test_and_set_bit(0, (void*)&dev->tbusy) != 0)
		printk(KERN_WARNING "%s: Transmitter access conflict.\n", dev->name);
	else {
		short length = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN;
		unsigned char *buf = skb->data;
		lp->stats.tx_bytes+=skb->len;
		hardware_send_packet(ioaddr, buf, length);
		dev->trans_start = jiffies;
	}
	dev_kfree_skb (skb);

	/* You might need to clean up and record Tx statistics here. */
	if (inw(ioaddr) == /*RU*/81)
		lp->stats.tx_aborted_errors++;

	return 0;
}

/*
 * The typical workload of the driver:
 *   Handle the network interface interrupts.
 */
static void net_interrupt(int irq, void *dev_id, struct pt_regs * regs)
{
	struct device *dev = dev_id;
	struct net_local *lp;
	int ioaddr, status, boguscount = 0;

	if (dev == NULL) {
		printk(KERN_WARNING "%s: irq %d for unknown device.\n", cardname, irq);
		return;
	}
	dev->interrupt = 1;

	ioaddr = dev->base_addr;
	lp = (struct net_local *)dev->priv;
	status = inw(ioaddr + 0);

	do {
		if (status /*& RX_INTR*/) {
			/* Got a packet(s). */
			net_rx(dev);
		}
		if (status /*& TX_INTR*/) {
			lp->stats.tx_packets++;
			dev->tbusy = 0;
			mark_bh(NET_BH);	/* Inform upper layers. */
		}
		if (status /*& COUNTERS_INTR*/) {
			/* Increment the appropriate 'localstats' field. */
			lp->stats.tx_window_errors++;
		}
	} while (++boguscount < 20) ;

	dev->interrupt = 0;
	return;
}

/* We have a good packet(s), get it/them out of the buffers. */
static void
net_rx(struct device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	int ioaddr = dev->base_addr;
	int boguscount = 10;

	do {
		int status = inw(ioaddr);
		int pkt_len = inw(ioaddr);
	  
		if (pkt_len == 0)		/* Read all the frames? */
			break;			/* Done for now */

		if (status & 0x40) {	/* There was an error. */
			lp->stats.rx_errors++;
			if (status & 0x20) lp->stats.rx_frame_errors++;
			if (status & 0x10) lp->stats.rx_over_errors++;
			if (status & 0x08) lp->stats.rx_crc_errors++;
			if (status & 0x04) lp->stats.rx_fifo_errors++;
		} else {
			/* Malloc up new buffer. */
			struct sk_buff *skb;

			lp->stats.rx_bytes+=pkt_len;
			
			skb = dev_alloc_skb(pkt_len);
			if (skb == NULL) {
				printk(KERN_NOTICE "%s: Memory squeeze, dropping packet.\n",
					   dev->name);
				lp->stats.rx_dropped++;
				break;
			}
			skb->dev = dev;

			/* 'skb->data' points to the start of sk_buff data area. */
			memcpy(skb_put(skb,pkt_len), (void*)dev->rmem_start,
				   pkt_len);
			/* or */
			insw(ioaddr, skb->data, (pkt_len + 1) >> 1);

			netif_rx(skb);
			lp->stats.rx_packets++;
		}
	} while (--boguscount);

	/*
	 * If any worth-while packets have been received, dev_rint()
	 * has done a mark_bh(NET_BH) for us and will work on them
	 * when we get to the bottom-half routine.
	 */
	return;
}

/* The inverse routine to net_open(). */
static int
net_close(struct device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	int ioaddr = dev->base_addr;

	lp->open_time = 0;

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

	/* Flush the Tx and disable Rx here. */

	disable_dma(dev->dma);

	/* If not IRQ or DMA jumpered, free up the line. */
	outw(0x00, ioaddr+0);	/* Release the physical interrupt line. */

	free_irq(dev->irq, dev);
	free_dma(dev->dma);

	/* Update the statistics here. */

	MOD_DEC_USE_COUNT;

	return 0;

}

/*
 * Get the current statistics.
 * This may be called with the card open or closed.
 */
static struct net_device_stats *net_get_stats(struct device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	short ioaddr = dev->base_addr;

	cli();
	/* Update the statistics from the device registers. */
	lp->stats.rx_missed_errors = inw(ioaddr+1);
	sti();

	return &lp->stats;
}

/*
 * Set or clear the multicast filter for this adaptor.
 * num_addrs == -1	Promiscuous mode, receive all packets
 * num_addrs == 0	Normal mode, clear multicast list
 * num_addrs > 0	Multicast mode, receive normal and MC packets,
 *			and do best-effort filtering.
 */
static void
set_multicast_list(struct device *dev)
{
	short ioaddr = dev->base_addr;
	if (dev->flags&IFF_PROMISC)
	{
		/* Enable promiscuous mode */
		outw(MULTICAST|PROMISC, ioaddr);
	}
	else if((dev->flags&IFF_ALLMULTI) || dev->mc_count > HW_MAX_ADDRS)
	{
		/* Disable promiscuous mode, use normal mode. */
		hardware_set_filter(NULL);

		outw(MULTICAST, ioaddr);
	}
	else if(dev->mc_count)
	{
		/* Walk the address list, and load the filter */
		hardware_set_filter(dev->mc_list);

		outw(MULTICAST, ioaddr);
	}
	else 
		outw(0, ioaddr);
}

#ifdef MODULE

static char devicename[9] = { 0, };
static struct device this_device = {
	devicename, /* will be inserted by linux/drivers/net/net_init.c */
	0, 0, 0, 0,
	0, 0,  /* I/O address, IRQ */
	0, 0, 0, NULL, netcard_probe };

static int io = 0x300;
static int irq = 0;
static int dma = 0;
static int mem = 0;

int init_module(void)
{
	int result;

	if (io == 0)
		printk(KERN_WARNING "%s: You shouldn't use auto-probing with insmod!\n",
			   cardname);

	/* Copy the parameters from insmod into the device structure. */
	this_device.base_addr = io;
	this_device.irq       = irq;
	this_device.dma       = dma;
	this_device.mem_start = mem;

	if ((result = register_netdev(&this_device)) != 0)
		return result;

	return 0;
}

void
cleanup_module(void)
{
	/* No need to check MOD_IN_USE, as sys_delete_module() checks. */
	unregister_netdev(&this_device);
	/*
	 * If we don't do this, we can't re-insmod it later.
	 * Release irq/dma here, when you have jumpered versions and
	 * allocate them in net_probe1().
	 */
	/*
	   free_irq(this_device.irq, dev);
	   free_dma(this_device.dma);
	*/
	release_region(this_device.base_addr, NETCARD_IO_EXTENT);

	if (this_device.priv)
		kfree_s(this_device.priv, sizeof(struct net_local));
}

#endif /* MODULE */

/*
 * Local variables:
 *  compile-command:
 *	gcc -D__KERNEL__ -Wall -Wstrict-prototypes -Wwrite-strings
 *	-Wredundant-decls -O2 -m486 -c skeleton.c
 *  version-control: t
 *  kept-new-versions: 5
 *  tab-width: 4
 *  c-indent-level: 4
 * End:
 */