sgiseeq.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 740 行 · 第 1/2 页

	 * adapter.  The following code is only safe iff the HPCDMA
	 * is not active!
	 */
	while ((td->tdma.cntinfo & (HPCDMA_XIU | HPCDMA_ETXD)) ==
	      (HPCDMA_XIU | HPCDMA_ETXD))
		td = (struct sgiseeq_tx_desc *)(long) KSEG1ADDR(td->tdma.pnext);
	if (td->tdma.cntinfo & HPCDMA_XIU) {
		hregs->tx_ndptr = CPHYSADDR(td);
		hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
	}
}

static inline void sgiseeq_tx(struct net_device *dev, struct sgiseeq_private *sp,
			      struct hpc3_ethregs *hregs,
			      struct sgiseeq_regs *sregs)
{
	struct sgiseeq_tx_desc *td;
	unsigned long status = hregs->tx_ctrl;
	int j;

	tx_maybe_reset_collisions(sp, sregs);

	if (!(status & (HPC3_ETXCTRL_ACTIVE | SEEQ_TSTAT_PTRANS))) {
		/* Oops, HPC detected some sort of error. */
		if (status & SEEQ_TSTAT_R16)
			sp->stats.tx_aborted_errors++;
		if (status & SEEQ_TSTAT_UFLOW)
			sp->stats.tx_fifo_errors++;
		if (status & SEEQ_TSTAT_LCLS)
			sp->stats.collisions++;
	}

	/* Ack 'em... */
	for (j = sp->tx_old; j != sp->tx_new; j = NEXT_TX(j)) {
		td = &sp->tx_desc[j];

		if (!(td->tdma.cntinfo & (HPCDMA_XIU)))
			break;
		if (!(td->tdma.cntinfo & (HPCDMA_ETXD))) {
			if (!(status & HPC3_ETXCTRL_ACTIVE)) {
				hregs->tx_ndptr = CPHYSADDR(td);
				hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
			}
			break;
		}
		sp->stats.tx_packets++;
		sp->tx_old = NEXT_TX(sp->tx_old);
		td->tdma.cntinfo &= ~(HPCDMA_XIU | HPCDMA_XIE);
		td->tdma.cntinfo |= HPCDMA_EOX;
	}
}

static irqreturn_t sgiseeq_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	struct net_device *dev = (struct net_device *) dev_id;
	struct sgiseeq_private *sp = netdev_priv(dev);
	struct hpc3_ethregs *hregs = sp->hregs;
	struct sgiseeq_regs *sregs = sp->sregs;

	spin_lock(&sp->tx_lock);

	/* Ack the IRQ and set software state. */
	hregs->rx_reset = HPC3_ERXRST_CLRIRQ;

	/* Always check for received packets. */
	sgiseeq_rx(dev, sp, hregs, sregs);

	/* Only check for tx acks if we have something queued. */
	if (sp->tx_old != sp->tx_new)
		sgiseeq_tx(dev, sp, hregs, sregs);

	if ((TX_BUFFS_AVAIL(sp) > 0) && netif_queue_stopped(dev)) {
		netif_wake_queue(dev);
	}
	spin_unlock(&sp->tx_lock);

	return IRQ_HANDLED;
}

static int sgiseeq_open(struct net_device *dev)
{
	struct sgiseeq_private *sp = netdev_priv(dev);
	struct sgiseeq_regs *sregs = sp->sregs;
	unsigned int irq = dev->irq;
	int err;

	if (request_irq(irq, sgiseeq_interrupt, 0, sgiseeqstr, dev)) {
		printk(KERN_ERR "Seeq8003: Can't get irq %d\n", dev->irq);
		err = -EAGAIN;
	}

	err = init_seeq(dev, sp, sregs);
	if (err)
		goto out_free_irq;

	netif_start_queue(dev);

	return 0;

out_free_irq:
	free_irq(irq, dev);

	return err;
}

static int sgiseeq_close(struct net_device *dev)
{
	struct sgiseeq_private *sp = netdev_priv(dev);
	struct sgiseeq_regs *sregs = sp->sregs;

	netif_stop_queue(dev);

	/* Shutdown the Seeq. */
	reset_hpc3_and_seeq(sp->hregs, sregs);

	return 0;
}

static inline int sgiseeq_reset(struct net_device *dev)
{
	struct sgiseeq_private *sp = netdev_priv(dev);
	struct sgiseeq_regs *sregs = sp->sregs;
	int err;

	err = init_seeq(dev, sp, sregs);
	if (err)
		return err;

	dev->trans_start = jiffies;
	netif_wake_queue(dev);

	return 0;
}

void sgiseeq_my_reset(void)
{
	printk("RESET!\n");
	sgiseeq_reset(gdev);
}

static int sgiseeq_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct sgiseeq_private *sp = netdev_priv(dev);
	struct hpc3_ethregs *hregs = sp->hregs;
	unsigned long flags;
	struct sgiseeq_tx_desc *td;
	int skblen, len, entry;

	spin_lock_irqsave(&sp->tx_lock, flags);

	/* Setup... */
	skblen = skb->len;
	len = (skblen <= ETH_ZLEN) ? ETH_ZLEN : skblen;
	sp->stats.tx_bytes += len;
	entry = sp->tx_new;
	td = &sp->tx_desc[entry];

	/* Create entry.  There are so many races with adding a new
	 * descriptor to the chain:
	 * 1) Assume that the HPC is off processing a DMA chain while
	 *    we are changing all of the following.
	 * 2) Do no allow the HPC to look at a new descriptor until
	 *    we have completely set up it's state.  This means, do
	 *    not clear HPCDMA_EOX in the current last descritptor
	 *    until the one we are adding looks consistent and could
	 *    be processes right now.
	 * 3) The tx interrupt code must notice when we've added a new
	 *    entry and the HPC got to the end of the chain before we
	 *    added this new entry and restarted it.
	 */
	memcpy((char *)(long)td->buf_vaddr, skb->data, skblen);
	if (len != skblen)
		memset((char *)(long)td->buf_vaddr + skb->len, 0, len-skblen);
	td->tdma.cntinfo = (len & HPCDMA_BCNT) |
	                   HPCDMA_XIU | HPCDMA_EOXP | HPCDMA_XIE | HPCDMA_EOX;
	if (sp->tx_old != sp->tx_new) {
		struct sgiseeq_tx_desc *backend;

		backend = &sp->tx_desc[PREV_TX(sp->tx_new)];
		backend->tdma.cntinfo &= ~HPCDMA_EOX;
	}
	sp->tx_new = NEXT_TX(sp->tx_new); /* Advance. */

	/* Maybe kick the HPC back into motion. */
	if (!(hregs->tx_ctrl & HPC3_ETXCTRL_ACTIVE))
		kick_tx(&sp->tx_desc[sp->tx_old], hregs);

	dev->trans_start = jiffies;
	dev_kfree_skb(skb);

	if (!TX_BUFFS_AVAIL(sp))
		netif_stop_queue(dev);
	spin_unlock_irqrestore(&sp->tx_lock, flags);

	return 0;
}

static void timeout(struct net_device *dev)
{
	printk(KERN_NOTICE "%s: transmit timed out, resetting\n", dev->name);
	sgiseeq_reset(dev);

	dev->trans_start = jiffies;
	netif_wake_queue(dev);
}

static struct net_device_stats *sgiseeq_get_stats(struct net_device *dev)
{
	struct sgiseeq_private *sp = netdev_priv(dev);

	return &sp->stats;
}

static void sgiseeq_set_multicast(struct net_device *dev)
{
}

static inline void setup_tx_ring(struct sgiseeq_tx_desc *buf, int nbufs)
{
	int i = 0;

	while (i < (nbufs - 1)) {
		buf[i].tdma.pnext = CPHYSADDR(buf + i + 1);
		buf[i].tdma.pbuf = 0;
		i++;
	}
	buf[i].tdma.pnext = CPHYSADDR(buf);
}

static inline void setup_rx_ring(struct sgiseeq_rx_desc *buf, int nbufs)
{
	int i = 0;

	while (i < (nbufs - 1)) {
		buf[i].rdma.pnext = CPHYSADDR(buf + i + 1);
		buf[i].rdma.pbuf = 0;
		i++;
	}
	buf[i].rdma.pbuf = 0;
	buf[i].rdma.pnext = CPHYSADDR(buf);
}

#define ALIGNED(x)  ((((unsigned long)(x)) + 0xf) & ~(0xf))

static int sgiseeq_init(struct hpc3_regs* regs, int irq)
{
	struct sgiseeq_init_block *sr;
	struct sgiseeq_private *sp;
	struct net_device *dev;
	int err, i;

	dev = alloc_etherdev(sizeof (struct sgiseeq_private));
	if (!dev) {
		printk(KERN_ERR "Sgiseeq: Etherdev alloc failed, aborting.\n");
		err = -ENOMEM;
		goto err_out;
	}
	sp = netdev_priv(dev);

	/* Make private data page aligned */
	sr = (struct sgiseeq_init_block *) get_zeroed_page(GFP_KERNEL);
	if (!sr) {
		printk(KERN_ERR "Sgiseeq: Page alloc failed, aborting.\n");
		err = -ENOMEM;
		goto err_out_free_dev;
	}
	sp->srings = sr;

#define EADDR_NVOFS     250
	for (i = 0; i < 3; i++) {
		unsigned short tmp = ip22_nvram_read(EADDR_NVOFS / 2 + i);

		dev->dev_addr[2 * i]     = tmp >> 8;
		dev->dev_addr[2 * i + 1] = tmp & 0xff;
	}

#ifdef DEBUG
	gpriv = sp;
	gdev = dev;
#endif
	sp->sregs = (struct sgiseeq_regs *) &hpc3c0->eth_ext[0];
	sp->hregs = &hpc3c0->ethregs;
	sp->name = sgiseeqstr;

	sp->rx_desc = (struct sgiseeq_rx_desc *)
	              KSEG1ADDR(ALIGNED(&sp->srings->rxvector[0]));
	dma_cache_wback_inv((unsigned long)&sp->srings->rxvector,
	                    sizeof(sp->srings->rxvector));
	sp->tx_desc = (struct sgiseeq_tx_desc *)
	              KSEG1ADDR(ALIGNED(&sp->srings->txvector[0]));
	dma_cache_wback_inv((unsigned long)&sp->srings->txvector,
	                    sizeof(sp->srings->txvector));

	/* A couple calculations now, saves many cycles later. */
	setup_rx_ring(sp->rx_desc, SEEQ_RX_BUFFERS);
	setup_tx_ring(sp->tx_desc, SEEQ_TX_BUFFERS);

	/* Reset the chip. */
	hpc3_eth_reset(sp->hregs);

	sp->is_edlc = !(sp->sregs->rw.rregs.collision_tx[0] & 0xff);
	if (sp->is_edlc)
		sp->control = SEEQ_CTRL_XCNT | SEEQ_CTRL_ACCNT |
			      SEEQ_CTRL_SFLAG | SEEQ_CTRL_ESHORT |
			      SEEQ_CTRL_ENCARR;

	dev->open		= sgiseeq_open;
	dev->stop		= sgiseeq_close;
	dev->hard_start_xmit	= sgiseeq_start_xmit;
	dev->tx_timeout		= timeout;
	dev->watchdog_timeo	= (200 * HZ) / 1000;
	dev->get_stats		= sgiseeq_get_stats;
	dev->set_multicast_list	= sgiseeq_set_multicast;
	dev->irq		= irq;

	if (register_netdev(dev)) {
		printk(KERN_ERR "Sgiseeq: Cannot register net device, "
		       "aborting.\n");
		err = -ENODEV;
		goto err_out_free_page;
	}

	printk(KERN_INFO "%s: SGI Seeq8003 ", dev->name);
	for (i = 0; i < 6; i++)
		printk("%2.2x%c", dev->dev_addr[i], i == 5 ? '\n' : ':');

	sp->next_module = root_sgiseeq_dev;
	root_sgiseeq_dev = dev;

	return 0;

err_out_free_page:
	free_page((unsigned long) sp);
err_out_free_dev:
	kfree(dev);

err_out:
	return err;
}

static int __init sgiseeq_probe(void)
{
	printk(version);

	/* On board adapter on 1st HPC is always present */
	return sgiseeq_init(hpc3c0, SGI_ENET_IRQ);
}

static void __exit sgiseeq_exit(void)
{
	struct net_device *next, *dev;
	struct sgiseeq_private *sp;
	int irq;

	for (dev = root_sgiseeq_dev; dev; dev = next) {
		sp = (struct sgiseeq_private *) netdev_priv(dev);
		next = sp->next_module;
		irq = dev->irq;
		unregister_netdev(dev);
		free_irq(irq, dev);
		free_page((unsigned long) sp);
		free_netdev(dev);
	}
}

module_init(sgiseeq_probe);
module_exit(sgiseeq_exit);

MODULE_LICENSE("GPL");