cs89x0.c

liunx下,以太网芯片8900的驱动程序说明

#endif
                 );
        netif_start_queue(dev);
	if (net_debug > 1)
		printk("cs89x0: net_open() succeeded\n");
	return 0;
bad_out:
	return ret;
}

static void net_timeout(struct net_device *dev)
{
	/* If we get here, some higher level has decided we are broken.
	   There should really be a "kick me" function call instead. */
	if (net_debug > 0) printk("%s: transmit timed out, %s?\n", dev->name,
		   tx_done(dev) ? "IRQ conflict ?" : "network cable problem");
	/* Try to restart the adaptor. */
	netif_wake_queue(dev);
}

static int net_send_packet(struct sk_buff *skb, struct net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);

	if (net_debug > 3) {
		printk("%s: sent %d byte packet of type %x\n",
			dev->name, skb->len,
			(skb->data[ETH_ALEN+ETH_ALEN] << 8) | skb->data[ETH_ALEN+ETH_ALEN+1]);
	}

	/* keep the upload from being interrupted, since we
                  ask the chip to start transmitting before the
                  whole packet has been completely uploaded. */

	spin_lock_irq(&lp->lock);
	netif_stop_queue(dev);

	/* initiate a transmit sequence */
	writeword(dev->base_addr, TX_CMD_PORT, lp->send_cmd);
	writeword(dev->base_addr, TX_LEN_PORT, skb->len);

	/* Test to see if the chip has allocated memory for the packet */
	if ((readreg(dev, PP_BusST) & READY_FOR_TX_NOW) == 0) {
		/*
		 * Gasp!  It hasn't.  But that shouldn't happen since
		 * we're waiting for TxOk, so return 1 and requeue this packet.
		 */
		
		spin_unlock_irq(&lp->lock);
		if (net_debug) printk("cs89x0: Tx buffer not free!\n");
		return 1;
	}
	/* Write the contents of the packet */
	writewords(dev->base_addr, TX_FRAME_PORT,skb->data,(skb->len+1) >>1);
	spin_unlock_irq(&lp->lock);
	lp->stats.tx_bytes += skb->len;
	dev->trans_start = jiffies;
	dev_kfree_skb (skb);

	/*
	 * We DO NOT call netif_wake_queue() here.
	 * We also DO NOT call netif_start_queue().
	 *
	 * Either of these would cause another bottom half run through
	 * net_send_packet() before this packet has fully gone out.  That causes
	 * us to hit the "Gasp!" above and the send is rescheduled.  it runs like
	 * a dog.  We just return and wait for the Tx completion interrupt handler
	 * to restart the netdevice layer
	 */

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

	ioaddr = dev->base_addr;
	lp = netdev_priv(dev);

	/* we MUST read all the events out of the ISQ, otherwise we'll never
           get interrupted again.  As a consequence, we can't have any limit
           on the number of times we loop in the interrupt handler.  The
           hardware guarantees that eventually we'll run out of events.  Of
           course, if you're on a slow machine, and packets are arriving
           faster than you can read them off, you're screwed.  Hasta la
           vista, baby!  */
	while ((status = readword(dev->base_addr, ISQ_PORT))) {
		if (net_debug > 4)printk("%s: event=%04x\n", dev->name, status);
		handled = 1;
		switch(status & ISQ_EVENT_MASK) {
		case ISQ_RECEIVER_EVENT:
			/* Got a packet(s). */
			net_rx(dev);
			break;
		case ISQ_TRANSMITTER_EVENT:
			lp->stats.tx_packets++;
			netif_wake_queue(dev);	/* Inform upper layers. */
			if ((status & (	TX_OK |
					TX_LOST_CRS |
					TX_SQE_ERROR |
					TX_LATE_COL |
					TX_16_COL)) != TX_OK) {
				if ((status & TX_OK) == 0) lp->stats.tx_errors++;
				if (status & TX_LOST_CRS) lp->stats.tx_carrier_errors++;
				if (status & TX_SQE_ERROR) lp->stats.tx_heartbeat_errors++;
				if (status & TX_LATE_COL) lp->stats.tx_window_errors++;
				if (status & TX_16_COL) lp->stats.tx_aborted_errors++;
			}
			break;
		case ISQ_BUFFER_EVENT:
			if (status & READY_FOR_TX) {
				/* we tried to transmit a packet earlier,
                                   but inexplicably ran out of buffers.
                                   That shouldn't happen since we only ever
                                   load one packet.  Shrug.  Do the right
                                   thing anyway. */
				netif_wake_queue(dev);	/* Inform upper layers. */
			}
			if (status & TX_UNDERRUN) {
				if (net_debug > 0) printk("%s: transmit underrun\n", dev->name);
                                lp->send_underrun++;
                                if (lp->send_underrun == 3) lp->send_cmd = TX_AFTER_381;
                                else if (lp->send_underrun == 6) lp->send_cmd = TX_AFTER_ALL;
				/* transmit cycle is done, although
				   frame wasn't transmitted - this
				   avoids having to wait for the upper
				   layers to timeout on us, in the
				   event of a tx underrun */
				netif_wake_queue(dev);	/* Inform upper layers. */
                        }
#if ALLOW_DMA
			if (lp->use_dma && (status & RX_DMA)) {
				int count = readreg(dev, PP_DmaFrameCnt);
				while(count) {
					if (net_debug > 5)
						printk("%s: receiving %d DMA frames\n", dev->name, count);
					if (net_debug > 2 && count >1)
						printk("%s: receiving %d DMA frames\n", dev->name, count);
					dma_rx(dev);
					if (--count == 0)
						count = readreg(dev, PP_DmaFrameCnt);
					if (net_debug > 2 && count > 0)
						printk("%s: continuing with %d DMA frames\n", dev->name, count);
				}
			}
#endif
			break;
		case ISQ_RX_MISS_EVENT:
			lp->stats.rx_missed_errors += (status >>6);
			break;
		case ISQ_TX_COL_EVENT:
			lp->stats.collisions += (status >>6);
			break;
		}
	}
	return IRQ_RETVAL(handled);
}

static void
count_rx_errors(int status, struct net_local *lp)
{
	lp->stats.rx_errors++;
	if (status & RX_RUNT) lp->stats.rx_length_errors++;
	if (status & RX_EXTRA_DATA) lp->stats.rx_length_errors++;
	if (status & RX_CRC_ERROR) if (!(status & (RX_EXTRA_DATA|RX_RUNT)))
		/* per str 172 */
		lp->stats.rx_crc_errors++;
	if (status & RX_DRIBBLE) lp->stats.rx_frame_errors++;
	return;
}

/* We have a good packet(s), get it/them out of the buffers. */
static void
net_rx(struct net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);
	struct sk_buff *skb;
	int status, length;

	int ioaddr = dev->base_addr;
	status = readword(ioaddr, RX_FRAME_PORT);
	length = readword(ioaddr, RX_FRAME_PORT);

	if ((status & RX_OK) == 0) {
		count_rx_errors(status, lp);
		return;
	}

	/* Malloc up new buffer. */
	skb = dev_alloc_skb(length + 2);
	if (skb == NULL) {
#if 0		/* Again, this seems a cruel thing to do */
		printk(KERN_WARNING "%s: Memory squeeze, dropping packet.\n", dev->name);
#endif
		lp->stats.rx_dropped++;
		return;
	}
	skb_reserve(skb, 2);	/* longword align L3 header */
	skb->dev = dev;

	readwords(ioaddr, RX_FRAME_PORT, skb_put(skb, length), length >> 1);
	if (length & 1)
		skb->data[length-1] = readword(ioaddr, RX_FRAME_PORT);

	if (net_debug > 3) {
		printk(	"%s: received %d byte packet of type %x\n",
			dev->name, length,
			(skb->data[ETH_ALEN+ETH_ALEN] << 8) | skb->data[ETH_ALEN+ETH_ALEN+1]);
	}

        skb->protocol=eth_type_trans(skb,dev);
	netif_rx(skb);
	dev->last_rx = jiffies;
	lp->stats.rx_packets++;
	lp->stats.rx_bytes += length;
}

#if ALLOW_DMA
static void release_dma_buff(struct net_local *lp)
{
	if (lp->dma_buff) {
		free_pages((unsigned long)(lp->dma_buff), get_order(lp->dmasize * 1024));
		lp->dma_buff = NULL;
	}
}
#endif

/* The inverse routine to net_open(). */
static int
net_close(struct net_device *dev)
{
#if ALLOW_DMA
	struct net_local *lp = netdev_priv(dev);
#endif

	netif_stop_queue(dev);
	
	writereg(dev, PP_RxCFG, 0);
	writereg(dev, PP_TxCFG, 0);
	writereg(dev, PP_BufCFG, 0);
	writereg(dev, PP_BusCTL, 0);

	free_irq(dev->irq, dev);

#if ALLOW_DMA
	if (lp->use_dma && lp->dma) {
		free_dma(dev->dma);
		release_dma_buff(lp);
	}
#endif

	/* Update the statistics here. */
	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 net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);
	unsigned long flags;

	spin_lock_irqsave(&lp->lock, flags);
	/* Update the statistics from the device registers. */
	lp->stats.rx_missed_errors += (readreg(dev, PP_RxMiss) >> 6);
	lp->stats.collisions += (readreg(dev, PP_TxCol) >> 6);
	spin_unlock_irqrestore(&lp->lock, flags);

	return &lp->stats;
}

static void set_multicast_list(struct net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);
	unsigned long flags;

	spin_lock_irqsave(&lp->lock, flags);
	if(dev->flags&IFF_PROMISC)
	{
		lp->rx_mode = RX_ALL_ACCEPT;
	}
	else if((dev->flags&IFF_ALLMULTI)||dev->mc_list)
	{
		/* The multicast-accept list is initialized to accept-all, and we
		   rely on higher-level filtering for now. */
		lp->rx_mode = RX_MULTCAST_ACCEPT;
	} 
	else
		lp->rx_mode = 0;

	writereg(dev, PP_RxCTL, DEF_RX_ACCEPT | lp->rx_mode);

	/* in promiscuous mode, we accept errored packets, so we have to enable interrupts on them also */
	writereg(dev, PP_RxCFG, lp->curr_rx_cfg |
	     (lp->rx_mode == RX_ALL_ACCEPT? (RX_CRC_ERROR_ENBL|RX_RUNT_ENBL|RX_EXTRA_DATA_ENBL) : 0));
	spin_unlock_irqrestore(&lp->lock, flags);
}


static int set_mac_address(struct net_device *dev, void *p)
{
	int i;
	struct sockaddr *addr = p;


	if (netif_running(dev))
		return -EBUSY;

	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);

	if (net_debug) {
		printk("%s: Setting MAC address to ", dev->name);
		for (i = 0; i < dev->addr_len; i++)
			printk(" %2.2x", dev->dev_addr[i]);
		printk(".\n");
	}
	/* set the Ethernet address */
	for (i=0; i < ETH_ALEN/2; i++)
		writereg(dev, PP_IA+i*2, dev->dev_addr[i*2] | (dev->dev_addr[i*2+1] << 8));

	return 0;
}

#ifdef MODULE

static struct net_device *dev_cs89x0;

/*
 * Support the 'debug' module parm even if we're compiled for non-debug to 
 * avoid breaking someone's startup scripts 
 */

static int io;
static int irq;
static int debug;
static char media[8];
static int duplex=-1;

static int use_dma;			/* These generate unused var warnings if ALLOW_DMA = 0 */
static int dma;
static int dmasize=16;			/* or 64 */

module_param(io, int, 0);
module_param(irq, int, 0);
module_param(debug, int, 0);
module_param_string(media, media, sizeof(media), 0);
module_param(duplex, int, 0);
module_param(dma , int, 0);
module_param(dmasize , int, 0);
module_param(use_dma , int, 0);
MODULE_PARM_DESC(io, "cs89x0 I/O base address");
MODULE_PARM_DESC(irq, "cs89x0 IRQ number");
#if DEBUGGING
MODULE_PARM_DESC(debug, "cs89x0 debug level (0-6)");
#else
MODULE_PARM_DESC(debug, "(ignored)");
#endif
MODULE_PARM_DESC(media, "Set cs89x0 adapter(s) media type(s) (rj45,bnc,aui)");
/* No other value than -1 for duplex seems to be currently interpreted */
MODULE_PARM_DESC(duplex, "(ignored)");
#if ALLOW_DMA
MODULE_PARM_DESC(dma , "cs89x0 ISA DMA channel; ignored if use_dma=0");
MODULE_PARM_DESC(dmasize , "cs89x0 DMA size in kB (16,64); ignored if use_dma=0");
MODULE_PARM_DESC(use_dma , "cs89x0 using DMA (0-1)");
#else
MODULE_PARM_DESC(dma , "(ignored)");
MODULE_PARM_DESC(dmasize , "(ignored)");
MODULE_PARM_DESC(use_dma , "(ignored)");
#endif

MODULE_AUTHOR("Mike Cruse, Russwll Nelson <[e-mail]>, Andrew Morton <[e-mail]>");
MODULE_LICENSE("GPL");


/*
* media=t             - specify media type
   or media=2
   or media=aui
   or medai=auto
* duplex=0            - specify forced half/full/autonegotiate duplex
* debug=#             - debug level


* Default Chip Configuration:
  * DMA Burst = enabled
  * IOCHRDY Enabled = enabled
    * UseSA = enabled
    * CS8900 defaults to half-duplex if not specified on command-line
    * CS8920 defaults to autoneg if not specified on command-line
    * Use reset defaults for other config parameters

* Assumptions:
  * media type specified is supported (circuitry is present)
  * if memory address is > 1MB, then required mem decode hw is present
  * if 10B-2, then agent other than driver will enable DC/DC converter
    (hw or software util)


*/

int
init_module(void)
{
	struct net_device *dev = alloc_etherdev(sizeof(struct net_local));
	struct net_local *lp;
	int ret = 0;

#if DEBUGGING
	net_debug = debug;
#else
	debug = 0;
#endif
	if (!dev)
		return -ENOMEM;

	dev->irq = irq;
	dev->base_addr = io;
	lp = netdev_priv(dev);

#if ALLOW_DMA
	if (use_dma) {
		lp->use_dma = use_dma;
		lp->dma = dma;
		lp->dmasize = dmasize;
	}
#endif

	spin_lock_init(&lp->lock);

        /* boy, they'd better get these right */
        if (!strcmp(media, "rj45"))
		lp->adapter_cnf = A_CNF_MEDIA_10B_T | A_CNF_10B_T;
	else if (!strcmp(media, "aui"))
		lp->adapter_cnf = A_CNF_MEDIA_AUI   | A_CNF_AUI;
	else if (!strcmp(media, "bnc"))
		lp->adapter_cnf = A_CNF_MEDIA_10B_2 | A_CNF_10B_2;
	else
		lp->adapter_cnf = A_CNF_MEDIA_10B_T | A_CNF_10B_T;

        if (duplex==-1)
		lp->auto_neg_cnf = AUTO_NEG_ENABLE;

        if (io == 0) {
                printk(KERN_ERR "cs89x0.c: Module autoprobing not allowed.\n");
                printk(KERN_ERR "cs89x0.c: Append io=0xNNN\n");
                ret = -EPERM;
		goto out;
        } else if (io <= 0x1ff) {
		ret = -ENXIO;
		goto out;
	}

#if ALLOW_DMA
	if (use_dma && dmasize != 16 && dmasize != 64) {
		printk(KERN_ERR "cs89x0.c: dma size must be either 16K or 64K, not %dK\n", dmasize);
		ret = -EPERM;
		goto out;
	}
#endif
	ret = cs89x0_probe1(dev, io, 1);
	if (ret)
		goto out;

	dev_cs89x0 = dev;
	return 0;
out:
	free_netdev(dev);
	return ret;
}

void
cleanup_module(void)
{
	unregister_netdev(dev_cs89x0);
	writeword(dev_cs89x0->base_addr, ADD_PORT, PP_ChipID);
	release_region(dev_cs89x0->base_addr, NETCARD_IO_EXTENT);
	free_netdev(dev_cs89x0);
}
#endif /* MODULE */

/*
 * Local variables:
 *  version-control: t
 *  kept-new-versions: 5
 *  c-indent-level: 8
 *  tab-width: 8
 * End:
 *
 */