aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/net/3c505.c
blob: 702bfb2a5e99d047f82e6d2b80e46c48396108e2 (plain) (tree)
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635

















































































































































































































































































                                                                                                  
                                                        









































                                                                                                                                                                       
 


                                      
 








































































































































































































































































































































                                                                                                                                    
                                                       









                                           
 


















































                                                                                                                                                                             
                                                                 















































































































































































                                                                                                                                                       
 
















































































































                                                                                                         
 







































                                                                                                             
 








                                                                           
 
























                                                                                                                      
 






                                                                                                          
 















































































                                                                                                   
                                                      
































































                                                                                    
 
















































































                                                                                                            
                            







                                                                               
                            

















































































































































































































































































































                                                                                                                                                 
                            



































                                                                                                         
                                














                                                                      
/*
 * Linux Ethernet device driver for the 3Com Etherlink Plus (3C505)
 *      By Craig Southeren, Juha Laiho and Philip Blundell
 *
 * 3c505.c      This module implements an interface to the 3Com
 *              Etherlink Plus (3c505) Ethernet card. Linux device
 *              driver interface reverse engineered from the Linux 3C509
 *              device drivers. Some 3C505 information gleaned from
 *              the Crynwr packet driver. Still this driver would not
 *              be here without 3C505 technical reference provided by
 *              3Com.
 *
 * $Id: 3c505.c,v 1.10 1996/04/16 13:06:27 phil Exp $
 *
 * Authors:     Linux 3c505 device driver by
 *                      Craig Southeren, <craigs@ineluki.apana.org.au>
 *              Final debugging by
 *                      Andrew Tridgell, <tridge@nimbus.anu.edu.au>
 *              Auto irq/address, tuning, cleanup and v1.1.4+ kernel mods by
 *                      Juha Laiho, <jlaiho@ichaos.nullnet.fi>
 *              Linux 3C509 driver by
 *                      Donald Becker, <becker@super.org>
 *			(Now at <becker@scyld.com>)
 *              Crynwr packet driver by
 *                      Krishnan Gopalan and Gregg Stefancik,
 *                      Clemson University Engineering Computer Operations.
 *                      Portions of the code have been adapted from the 3c505
 *                         driver for NCSA Telnet by Bruce Orchard and later
 *                         modified by Warren Van Houten and krus@diku.dk.
 *              3C505 technical information provided by
 *                      Terry Murphy, of 3Com Network Adapter Division
 *              Linux 1.3.0 changes by
 *                      Alan Cox <Alan.Cox@linux.org>
 *              More debugging, DMA support, currently maintained by
 *                      Philip Blundell <philb@gnu.org>
 *              Multicard/soft configurable dma channel/rev 2 hardware support
 *                      by Christopher Collins <ccollins@pcug.org.au>
 *		Ethtool support (jgarzik), 11/17/2001
 */

#define DRV_NAME	"3c505"
#define DRV_VERSION	"1.10a"


/* Theory of operation:
 *
 * The 3c505 is quite an intelligent board.  All communication with it is done
 * by means of Primary Command Blocks (PCBs); these are transferred using PIO
 * through the command register.  The card has 256k of on-board RAM, which is
 * used to buffer received packets.  It might seem at first that more buffers
 * are better, but in fact this isn't true.  From my tests, it seems that
 * more than about 10 buffers are unnecessary, and there is a noticeable
 * performance hit in having more active on the card.  So the majority of the
 * card's memory isn't, in fact, used.  Sadly, the card only has one transmit
 * buffer and, short of loading our own firmware into it (which is what some
 * drivers resort to) there's nothing we can do about this.
 *
 * We keep up to 4 "receive packet" commands active on the board at a time.
 * When a packet comes in, so long as there is a receive command active, the
 * board will send us a "packet received" PCB and then add the data for that
 * packet to the DMA queue.  If a DMA transfer is not already in progress, we
 * set one up to start uploading the data.  We have to maintain a list of
 * backlogged receive packets, because the card may decide to tell us about
 * a newly-arrived packet at any time, and we may not be able to start a DMA
 * transfer immediately (ie one may already be going on).  We can't NAK the
 * PCB, because then it would throw the packet away.
 *
 * Trying to send a PCB to the card at the wrong moment seems to have bad
 * effects.  If we send it a transmit PCB while a receive DMA is happening,
 * it will just NAK the PCB and so we will have wasted our time.  Worse, it
 * sometimes seems to interrupt the transfer.  The majority of the low-level
 * code is protected by one huge semaphore -- "busy" -- which is set whenever
 * it probably isn't safe to do anything to the card.  The receive routine
 * must gain a lock on "busy" before it can start a DMA transfer, and the
 * transmit routine must gain a lock before it sends the first PCB to the card.
 * The send_pcb() routine also has an internal semaphore to protect it against
 * being re-entered (which would be disastrous) -- this is needed because
 * several things can happen asynchronously (re-priming the receiver and
 * asking the card for statistics, for example).  send_pcb() will also refuse
 * to talk to the card at all if a DMA upload is happening.  The higher-level
 * networking code will reschedule a later retry if some part of the driver
 * is blocked.  In practice, this doesn't seem to happen very often.
 */

/* This driver may now work with revision 2.x hardware, since all the read
 * operations on the HCR have been removed (we now keep our own softcopy).
 * But I don't have an old card to test it on.
 *
 * This has had the bad effect that the autoprobe routine is now a bit
 * less friendly to other devices.  However, it was never very good.
 * before, so I doubt it will hurt anybody.
 */

/* The driver is a mess.  I took Craig's and Juha's code, and hacked it firstly
 * to make it more reliable, and secondly to add DMA mode.  Many things could
 * probably be done better; the concurrency protection is particularly awful.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>
#include <linux/ethtool.h>
#include <linux/delay.h>
#include <linux/bitops.h>

#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/dma.h>

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/init.h>

#include "3c505.h"

/*********************************************************
 *
 *  define debug messages here as common strings to reduce space
 *
 *********************************************************/

static const char filename[] = __FILE__;

static const char timeout_msg[] = "*** timeout at %s:%s (line %d) ***\n";
#define TIMEOUT_MSG(lineno) \
	printk(timeout_msg, filename,__FUNCTION__,(lineno))

static const char invalid_pcb_msg[] =
"*** invalid pcb length %d at %s:%s (line %d) ***\n";
#define INVALID_PCB_MSG(len) \
	printk(invalid_pcb_msg, (len),filename,__FUNCTION__,__LINE__)

static char search_msg[] __initdata = KERN_INFO "%s: Looking for 3c505 adapter at address %#x...";

static char stilllooking_msg[] __initdata = "still looking...";

static char found_msg[] __initdata = "found.\n";

static char notfound_msg[] __initdata = "not found (reason = %d)\n";

static char couldnot_msg[] __initdata = KERN_INFO "%s: 3c505 not found\n";

/*********************************************************
 *
 *  various other debug stuff
 *
 *********************************************************/

#ifdef ELP_DEBUG
static int elp_debug = ELP_DEBUG;
#else
static int elp_debug;
#endif
#define debug elp_debug

/*
 *  0 = no messages (well, some)
 *  1 = messages when high level commands performed
 *  2 = messages when low level commands performed
 *  3 = messages when interrupts received
 */

/*****************************************************************
 *
 * useful macros
 *
 *****************************************************************/

#ifndef	TRUE
#define	TRUE	1
#endif

#ifndef	FALSE
#define	FALSE	0
#endif


/*****************************************************************
 *
 * List of I/O-addresses we try to auto-sense
 * Last element MUST BE 0!
 *****************************************************************/

static int addr_list[] __initdata = {0x300, 0x280, 0x310, 0};

/* Dma Memory related stuff */

static unsigned long dma_mem_alloc(int size)
{
	int order = get_order(size);
	return __get_dma_pages(GFP_KERNEL, order);
}


/*****************************************************************
 *
 * Functions for I/O (note the inline !)
 *
 *****************************************************************/

static inline unsigned char inb_status(unsigned int base_addr)
{
	return inb(base_addr + PORT_STATUS);
}

static inline int inb_command(unsigned int base_addr)
{
	return inb(base_addr + PORT_COMMAND);
}

static inline void outb_control(unsigned char val, struct net_device *dev)
{
	outb(val, dev->base_addr + PORT_CONTROL);
	((elp_device *)(dev->priv))->hcr_val = val;
}

#define HCR_VAL(x)   (((elp_device *)((x)->priv))->hcr_val)

static inline void outb_command(unsigned char val, unsigned int base_addr)
{
	outb(val, base_addr + PORT_COMMAND);
}

static inline unsigned int backlog_next(unsigned int n)
{
	return (n + 1) % BACKLOG_SIZE;
}

/*****************************************************************
 *
 *  useful functions for accessing the adapter
 *
 *****************************************************************/

/*
 * use this routine when accessing the ASF bits as they are
 * changed asynchronously by the adapter
 */

/* get adapter PCB status */
#define	GET_ASF(addr) \
	(get_status(addr)&ASF_PCB_MASK)

static inline int get_status(unsigned int base_addr)
{
	unsigned long timeout = jiffies + 10*HZ/100;
	register int stat1;
	do {
		stat1 = inb_status(base_addr);
	} while (stat1 != inb_status(base_addr) && time_before(jiffies, timeout));
	if (time_after_eq(jiffies, timeout))
		TIMEOUT_MSG(__LINE__);
	return stat1;
}

static inline void set_hsf(struct net_device *dev, int hsf)
{
	elp_device *adapter = dev->priv;
	unsigned long flags;

	spin_lock_irqsave(&adapter->lock, flags);
	outb_control((HCR_VAL(dev) & ~HSF_PCB_MASK) | hsf, dev);
	spin_unlock_irqrestore(&adapter->lock, flags);
}

static int start_receive(struct net_device *, pcb_struct *);

static inline void adapter_reset(struct net_device *dev)
{
	unsigned long timeout;
	elp_device *adapter = dev->priv;
	unsigned char orig_hcr = adapter->hcr_val;

	outb_control(0, dev);

	if (inb_status(dev->base_addr) & ACRF) {
		do {
			inb_command(dev->base_addr);
			timeout = jiffies + 2*HZ/100;
			while (time_before_eq(jiffies, timeout) && !(inb_status(dev->base_addr) & ACRF));
		} while (inb_status(dev->base_addr) & ACRF);
		set_hsf(dev, HSF_PCB_NAK);
	}
	outb_control(adapter->hcr_val | ATTN | DIR, dev);
	mdelay(10);
	outb_control(adapter->hcr_val & ~ATTN, dev);
	mdelay(10);
	outb_control(adapter->hcr_val | FLSH, dev);
	mdelay(10);
	outb_control(adapter->hcr_val & ~FLSH, dev);
	mdelay(10);

	outb_control(orig_hcr, dev);
	if (!start_receive(dev, &adapter->tx_pcb))
		printk(KERN_ERR "%s: start receive command failed \n", dev->name);
}

/* Check to make sure that a DMA transfer hasn't timed out.  This should
 * never happen in theory, but seems to occur occasionally if the card gets
 * prodded at the wrong time.
 */
static inline void check_3c505_dma(struct net_device *dev)
{
	elp_device *adapter = dev->priv;
	if (adapter->dmaing && time_after(jiffies, adapter->current_dma.start_time + 10)) {
		unsigned long flags, f;
		printk(KERN_ERR "%s: DMA %s timed out, %d bytes left\n", dev->name, adapter->current_dma.direction ? "download" : "upload", get_dma_residue(dev->dma));
		spin_lock_irqsave(&adapter->lock, flags);
		adapter->dmaing = 0;
		adapter->busy = 0;

		f=claim_dma_lock();
		disable_dma(dev->dma);
		release_dma_lock(f);

		if (adapter->rx_active)
			adapter->rx_active--;
		outb_control(adapter->hcr_val & ~(DMAE | TCEN | DIR), dev);
		spin_unlock_irqrestore(&adapter->lock, flags);
	}
}

/* Primitive functions used by send_pcb() */
static inline unsigned int send_pcb_slow(unsigned int base_addr, unsigned char byte)
{
	unsigned long timeout;
	outb_command(byte, base_addr);
	for (timeout = jiffies + 5*HZ/100; time_before(jiffies, timeout);) {
		if (inb_status(base_addr) & HCRE)
			return FALSE;
	}
	printk(KERN_WARNING "3c505: send_pcb_slow timed out\n");
	return TRUE;
}

static inline unsigned int send_pcb_fast(unsigned int base_addr, unsigned char byte)
{
	unsigned int timeout;
	outb_command(byte, base_addr);
	for (timeout = 0; timeout < 40000; timeout++) {
		if (inb_status(base_addr) & HCRE)
			return FALSE;
	}
	printk(KERN_WARNING "3c505: send_pcb_fast timed out\n");
	return TRUE;
}

/* Check to see if the receiver needs restarting, and kick it if so */
static inline void prime_rx(struct net_device *dev)
{
	elp_device *adapter = dev->priv;
	while (adapter->rx_active < ELP_RX_PCBS && netif_running(dev)) {
		if (!start_receive(dev, &adapter->itx_pcb))
			break;
	}
}

/*****************************************************************
 *
 * send_pcb
 *   Send a PCB to the adapter.
 *
 *	output byte to command reg  --<--+
 *	wait until HCRE is non zero      |
 *	loop until all bytes sent   -->--+
 *	set HSF1 and HSF2 to 1
 *	output pcb length
 *	wait until ASF give ACK or NAK
 *	set HSF1 and HSF2 to 0
 *
 *****************************************************************/

/* This can be quite slow -- the adapter is allowed to take up to 40ms
 * to respond to the initial interrupt.
 *
 * We run initially with interrupts turned on, but with a semaphore set
 * so that nobody tries to re-enter this code.  Once the first byte has
 * gone through, we turn interrupts off and then send the others (the
 * timeout is reduced to 500us).
 */

static int send_pcb(struct net_device *dev, pcb_struct * pcb)
{
	int i;
	unsigned long timeout;
	elp_device *adapter = dev->priv;
	unsigned long flags;

	check_3c505_dma(dev);

	if (adapter->dmaing && adapter->current_dma.direction == 0)
		return FALSE;

	/* Avoid contention */
	if (test_and_set_bit(1, &adapter->send_pcb_semaphore)) {
		if (elp_debug >= 3) {
			printk(KERN_DEBUG "%s: send_pcb entered while threaded\n", dev->name);
		}
		return FALSE;
	}
	/*
	 * load each byte into the command register and
	 * wait for the HCRE bit to indicate the adapter
	 * had read the byte
	 */
	set_hsf(dev, 0);

	if (send_pcb_slow(dev->base_addr, pcb->command))
		goto abort;

	spin_lock_irqsave(&adapter->lock, flags);

	if (send_pcb_fast(dev->base_addr, pcb->length))
		goto sti_abort;

	for (i = 0; i < pcb->length; i++) {
		if (send_pcb_fast(dev->base_addr, pcb->data.raw[i]))
			goto sti_abort;
	}

	outb_control(adapter->hcr_val | 3, dev);	/* signal end of PCB */
	outb_command(2 + pcb->length, dev->base_addr);

	/* now wait for the acknowledgement */
	spin_unlock_irqrestore(&adapter->lock, flags);

	for (timeout = jiffies + 5*HZ/100; time_before(jiffies, timeout);) {
		switch (GET_ASF(dev->base_addr)) {
		case ASF_PCB_ACK:
			adapter->send_pcb_semaphore = 0;
			return TRUE;

		case ASF_PCB_NAK:
#ifdef ELP_DEBUG
			printk(KERN_DEBUG "%s: send_pcb got NAK\n", dev->name);
#endif
			goto abort;
		}
	}

	if (elp_debug >= 1)
		printk(KERN_DEBUG "%s: timeout waiting for PCB acknowledge (status %02x)\n", dev->name, inb_status(dev->base_addr));
	goto abort;

      sti_abort:
	spin_unlock_irqrestore(&adapter->lock, flags);
      abort:
	adapter->send_pcb_semaphore = 0;
	return FALSE;
}


/*****************************************************************
 *
 * receive_pcb
 *   Read a PCB from the adapter
 *
 *	wait for ACRF to be non-zero        ---<---+
 *	input a byte                               |
 *	if ASF1 and ASF2 were not both one         |
 *		before byte was read, loop      --->---+
 *	set HSF1 and HSF2 for ack
 *
 *****************************************************************/

static int receive_pcb(struct net_device *dev, pcb_struct * pcb)
{
	int i, j;
	int total_length;
	int stat;
	unsigned long timeout;
	unsigned long flags;

	elp_device *adapter = dev->priv;

	set_hsf(dev, 0);

	/* get the command code */
	timeout = jiffies + 2*HZ/100;
	while (((stat = get_status(dev->base_addr)) & ACRF) == 0 && time_before(jiffies, timeout));
	if (time_after_eq(jiffies, timeout)) {
		TIMEOUT_MSG(__LINE__);
		return FALSE;
	}
	pcb->command = inb_command(dev->base_addr);

	/* read the data length */
	timeout = jiffies + 3*HZ/100;
	while (((stat = get_status(dev->base_addr)) & ACRF) == 0 && time_before(jiffies, timeout));
	if (time_after_eq(jiffies, timeout)) {
		TIMEOUT_MSG(__LINE__);
		printk(KERN_INFO "%s: status %02x\n", dev->name, stat);
		return FALSE;
	}
	pcb->length = inb_command(dev->base_addr);

	if (pcb->length > MAX_PCB_DATA) {
		INVALID_PCB_MSG(pcb->length);
		adapter_reset(dev);
		return FALSE;
	}
	/* read the data */
	spin_lock_irqsave(&adapter->lock, flags);
	i = 0;
	do {
		j = 0;
		while (((stat = get_status(dev->base_addr)) & ACRF) == 0 && j++ < 20000);
		pcb->data.raw[i++] = inb_command(dev->base_addr);
		if (i > MAX_PCB_DATA)
			INVALID_PCB_MSG(i);
	} while ((stat & ASF_PCB_MASK) != ASF_PCB_END && j < 20000);
	spin_unlock_irqrestore(&adapter->lock, flags);
	if (j >= 20000) {
		TIMEOUT_MSG(__LINE__);
		return FALSE;
	}
	/* woops, the last "data" byte was really the length! */
	total_length = pcb->data.raw[--i];

	/* safety check total length vs data length */
	if (total_length != (pcb->length + 2)) {
		if (elp_debug >= 2)
			printk(KERN_WARNING "%s: mangled PCB received\n", dev->name);
		set_hsf(dev, HSF_PCB_NAK);
		return FALSE;
	}

	if (pcb->command == CMD_RECEIVE_PACKET_COMPLETE) {
		if (test_and_set_bit(0, (void *) &adapter->busy)) {
			if (backlog_next(adapter->rx_backlog.in) == adapter->rx_backlog.out) {
				set_hsf(dev, HSF_PCB_NAK);
				printk(KERN_WARNING "%s: PCB rejected, transfer in progress and backlog full\n", dev->name);
				pcb->command = 0;
				return TRUE;
			} else {
				pcb->command = 0xff;
			}
		}
	}
	set_hsf(dev, HSF_PCB_ACK);
	return TRUE;
}

/******************************************************
 *
 *  queue a receive command on the adapter so we will get an
 *  interrupt when a packet is received.
 *
 ******************************************************/

static int start_receive(struct net_device *dev, pcb_struct * tx_pcb)
{
	int status;
	elp_device *adapter = dev->priv;

	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: restarting receiver\n", dev->name);
	tx_pcb->command = CMD_RECEIVE_PACKET;
	tx_pcb->length = sizeof(struct Rcv_pkt);
	tx_pcb->data.rcv_pkt.buf_seg
	    = tx_pcb->data.rcv_pkt.buf_ofs = 0;		/* Unused */
	tx_pcb->data.rcv_pkt.buf_len = 1600;
	tx_pcb->data.rcv_pkt.timeout = 0;	/* set timeout to zero */
	status = send_pcb(dev, tx_pcb);
	if (status)
		adapter->rx_active++;
	return status;
}

/******************************************************
 *
 * extract a packet from the adapter
 * this routine is only called from within the interrupt
 * service routine, so no cli/sti calls are needed
 * note that the length is always assumed to be even
 *
 ******************************************************/

static void receive_packet(struct net_device *dev, int len)
{
	int rlen;
	elp_device *adapter = dev->priv;
	void *target;
	struct sk_buff *skb;
	unsigned long flags;

	rlen = (len + 1) & ~1;
	skb = dev_alloc_skb(rlen + 2);

	if (!skb) {
		printk(KERN_WARNING "%s: memory squeeze, dropping packet\n", dev->name);
		target = adapter->dma_buffer;
		adapter->current_dma.target = NULL;
		/* FIXME: stats */
		return;
	}

	skb_reserve(skb, 2);
	target = skb_put(skb, rlen);
	if ((unsigned long)(target + rlen) >= MAX_DMA_ADDRESS) {
		adapter->current_dma.target = target;
		target = adapter->dma_buffer;
	} else {
		adapter->current_dma.target = NULL;
	}

	/* if this happens, we die */
	if (test_and_set_bit(0, (void *) &adapter->dmaing))
		printk(KERN_ERR "%s: rx blocked, DMA in progress, dir %d\n", dev->name, adapter->current_dma.direction);

	skb->dev = dev;
	adapter->current_dma.direction = 0;
	adapter->current_dma.length = rlen;
	adapter->current_dma.skb = skb;
	adapter->current_dma.start_time = jiffies;

	outb_control(adapter->hcr_val | DIR | TCEN | DMAE, dev);

	flags=claim_dma_lock();
	disable_dma(dev->dma);
	clear_dma_ff(dev->dma);
	set_dma_mode(dev->dma, 0x04);	/* dma read */
	set_dma_addr(dev->dma, isa_virt_to_bus(target));
	set_dma_count(dev->dma, rlen);
	enable_dma(dev->dma);
	release_dma_lock(flags);

	if (elp_debug >= 3) {
		printk(KERN_DEBUG "%s: rx DMA transfer started\n", dev->name);
	}

	if (adapter->rx_active)
		adapter->rx_active--;

	if (!adapter->busy)
		printk(KERN_WARNING "%s: receive_packet called, busy not set.\n", dev->name);
}

/******************************************************
 *
 * interrupt handler
 *
 ******************************************************/

static irqreturn_t elp_interrupt(int irq, void *dev_id)
{
	int len;
	int dlen;
	int icount = 0;
	struct net_device *dev;
	elp_device *adapter;
	unsigned long timeout;

	dev = dev_id;
	adapter = (elp_device *) dev->priv;

	spin_lock(&adapter->lock);

	do {
		/*
		 * has a DMA transfer finished?
		 */
		if (inb_status(dev->base_addr) & DONE) {
			if (!adapter->dmaing) {
				printk(KERN_WARNING "%s: phantom DMA completed\n", dev->name);
			}
			if (elp_debug >= 3) {
				printk(KERN_DEBUG "%s: %s DMA complete, status %02x\n", dev->name, adapter->current_dma.direction ? "tx" : "rx", inb_status(dev->base_addr));
			}

			outb_control(adapter->hcr_val & ~(DMAE | TCEN | DIR), dev);
			if (adapter->current_dma.direction) {
				dev_kfree_skb_irq(adapter->current_dma.skb);
			} else {
				struct sk_buff *skb = adapter->current_dma.skb;
				if (skb) {
					if (adapter->current_dma.target) {
				  	/* have already done the skb_put() */
				  	memcpy(adapter->current_dma.target, adapter->dma_buffer, adapter->current_dma.length);
					}
					skb->protocol = eth_type_trans(skb,dev);
					adapter->stats.rx_bytes += skb->len;
					netif_rx(skb);
					dev->last_rx = jiffies;
				}
			}
			adapter->dmaing = 0;
			if (adapter->rx_backlog.in != adapter->rx_backlog.out) {
				int t = adapter->rx_backlog.length[adapter->rx_backlog.out];
				adapter->rx_backlog.out = backlog_next(adapter->rx_backlog.out);
				if (elp_debug >= 2)
					printk(KERN_DEBUG "%s: receiving backlogged packet (%d)\n", dev->name, t);
				receive_packet(dev, t);
			} else {
				adapter->busy = 0;
			}
		} else {
			/* has one timed out? */
			check_3c505_dma(dev);
		}

		/*
		 * receive a PCB from the adapter
		 */
		timeout = jiffies + 3*HZ/100;
		while ((inb_status(dev->base_addr) & ACRF) != 0 && time_before(jiffies, timeout)) {
			if (receive_pcb(dev, &adapter->irx_pcb)) {
				switch (adapter->irx_pcb.command)
				{
				case 0:
					break;
					/*
					 * received a packet - this must be handled fast
					 */
				case 0xff:
				case CMD_RECEIVE_PACKET_COMPLETE:
					/* if the device isn't open, don't pass packets up the stack */
					if (!netif_running(dev))
						break;
					len = adapter->irx_pcb.data.rcv_resp.pkt_len;
					dlen = adapter->irx_pcb.data.rcv_resp.buf_len;
					if (adapter->irx_pcb.data.rcv_resp.timeout != 0) {
						printk(KERN_ERR "%s: interrupt - packet not received correctly\n", dev->name);
					} else {
						if (elp_debug >= 3) {
							printk(KERN_DEBUG "%s: interrupt - packet received of length %i (%i)\n", dev->name, len, dlen);
						}
						if (adapter->irx_pcb.command == 0xff) {
							if (elp_debug >= 2)
								printk(KERN_DEBUG "%s: adding packet to backlog (len = %d)\n", dev->name, dlen);
							adapter->rx_backlog.length[adapter->rx_backlog.in] = dlen;
							adapter->rx_backlog.in = backlog_next(adapter->rx_backlog.in);
						} else {
							receive_packet(dev, dlen);
						}
						if (elp_debug >= 3)
							printk(KERN_DEBUG "%s: packet received\n", dev->name);
					}
					break;

					/*
					 * 82586 configured correctly
					 */
				case CMD_CONFIGURE_82586_RESPONSE:
					adapter->got[CMD_CONFIGURE_82586] = 1;
					if (elp_debug >= 3)
						printk(KERN_DEBUG "%s: interrupt - configure response received\n", dev->name);
					break;

					/*
					 * Adapter memory configuration
					 */
				case CMD_CONFIGURE_ADAPTER_RESPONSE:
					adapter->got[CMD_CONFIGURE_ADAPTER_MEMORY] = 1;
					if (elp_debug >= 3)
						printk(KERN_DEBUG "%s: Adapter memory configuration %s.\n", dev->name,
						       adapter->irx_pcb.data.failed ? "failed" : "succeeded");
					break;

					/*
					 * Multicast list loading
					 */
				case CMD_LOAD_MULTICAST_RESPONSE:
					adapter->got[CMD_LOAD_MULTICAST_LIST] = 1;
					if (elp_debug >= 3)
						printk(KERN_DEBUG "%s: Multicast address list loading %s.\n", dev->name,
						       adapter->irx_pcb.data.failed ? "failed" : "succeeded");
					break;

					/*
					 * Station address setting
					 */
				case CMD_SET_ADDRESS_RESPONSE:
					adapter->got[CMD_SET_STATION_ADDRESS] = 1;
					if (elp_debug >= 3)
						printk(KERN_DEBUG "%s: Ethernet address setting %s.\n", dev->name,
						       adapter->irx_pcb.data.failed ? "failed" : "succeeded");
					break;


					/*
					 * received board statistics
					 */
				case CMD_NETWORK_STATISTICS_RESPONSE:
					adapter->stats.rx_packets += adapter->irx_pcb.data.netstat.tot_recv;
					adapter->stats.tx_packets += adapter->irx_pcb.data.netstat.tot_xmit;
					adapter->stats.rx_crc_errors += adapter->irx_pcb.data.netstat.err_CRC;
					adapter->stats.rx_frame_errors += adapter->irx_pcb.data.netstat.err_align;
					adapter->stats.rx_fifo_errors += adapter->irx_pcb.data.netstat.err_ovrrun;
					adapter->stats.rx_over_errors += adapter->irx_pcb.data.netstat.err_res;
					adapter->got[CMD_NETWORK_STATISTICS] = 1;
					if (elp_debug >= 3)
						printk(KERN_DEBUG "%s: interrupt - statistics response received\n", dev->name);
					break;

					/*
					 * sent a packet
					 */
				case CMD_TRANSMIT_PACKET_COMPLETE:
					if (elp_debug >= 3)
						printk(KERN_DEBUG "%s: interrupt - packet sent\n", dev->name);
					if (!netif_running(dev))
						break;
					switch (adapter->irx_pcb.data.xmit_resp.c_stat) {
					case 0xffff:
						adapter->stats.tx_aborted_errors++;
						printk(KERN_INFO "%s: transmit timed out, network cable problem?\n", dev->name);
						break;
					case 0xfffe:
						adapter->stats.tx_fifo_errors++;
						printk(KERN_INFO "%s: transmit timed out, FIFO underrun\n", dev->name);
						break;
					}
					netif_wake_queue(dev);
					break;

					/*
					 * some unknown PCB
					 */
				default:
					printk(KERN_DEBUG "%s: unknown PCB received - %2.2x\n", dev->name, adapter->irx_pcb.command);
					break;
				}
			} else {
				printk(KERN_WARNING "%s: failed to read PCB on interrupt\n", dev->name);
				adapter_reset(dev);
			}
		}

	} while (icount++ < 5 && (inb_status(dev->base_addr) & (ACRF | DONE)));

	prime_rx(dev);

	/*
	 * indicate no longer in interrupt routine
	 */
	spin_unlock(&adapter->lock);
	return IRQ_HANDLED;
}


/******************************************************
 *
 * open the board
 *
 ******************************************************/

static int elp_open(struct net_device *dev)
{
	elp_device *adapter;
	int retval;

	adapter = dev->priv;

	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: request to open device\n", dev->name);

	/*
	 * make sure we actually found the device
	 */
	if (adapter == NULL) {
		printk(KERN_ERR "%s: Opening a non-existent physical device\n", dev->name);
		return -EAGAIN;
	}
	/*
	 * disable interrupts on the board
	 */
	outb_control(0, dev);

	/*
	 * clear any pending interrupts
	 */
	inb_command(dev->base_addr);
	adapter_reset(dev);

	/*
	 * no receive PCBs active
	 */
	adapter->rx_active = 0;

	adapter->busy = 0;
	adapter->send_pcb_semaphore = 0;
	adapter->rx_backlog.in = 0;
	adapter->rx_backlog.out = 0;

	spin_lock_init(&adapter->lock);

	/*
	 * install our interrupt service routine
	 */
	if ((retval = request_irq(dev->irq, &elp_interrupt, 0, dev->name, dev))) {
		printk(KERN_ERR "%s: could not allocate IRQ%d\n", dev->name, dev->irq);
		return retval;
	}
	if ((retval = request_dma(dev->dma, dev->name))) {
		free_irq(dev->irq, dev);
		printk(KERN_ERR "%s: could not allocate DMA%d channel\n", dev->name, dev->dma);
		return retval;
	}
	adapter->dma_buffer = (void *) dma_mem_alloc(DMA_BUFFER_SIZE);
	if (!adapter->dma_buffer) {
		printk(KERN_ERR "%s: could not allocate DMA buffer\n", dev->name);
		free_dma(dev->dma);
		free_irq(dev->irq, dev);
		return -ENOMEM;
	}
	adapter->dmaing = 0;

	/*
	 * enable interrupts on the board
	 */
	outb_control(CMDE, dev);

	/*
	 * configure adapter memory: we need 10 multicast addresses, default==0
	 */
	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: sending 3c505 memory configuration command\n", dev->name);
	adapter->tx_pcb.command = CMD_CONFIGURE_ADAPTER_MEMORY;
	adapter->tx_pcb.data.memconf.cmd_q = 10;
	adapter->tx_pcb.data.memconf.rcv_q = 20;
	adapter->tx_pcb.data.memconf.mcast = 10;
	adapter->tx_pcb.data.memconf.frame = 20;
	adapter->tx_pcb.data.memconf.rcv_b = 20;
	adapter->tx_pcb.data.memconf.progs = 0;
	adapter->tx_pcb.length = sizeof(struct Memconf);
	adapter->got[CMD_CONFIGURE_ADAPTER_MEMORY] = 0;
	if (!send_pcb(dev, &adapter->tx_pcb))
		printk(KERN_ERR "%s: couldn't send memory configuration command\n", dev->name);
	else {
		unsigned long timeout = jiffies + TIMEOUT;
		while (adapter->got[CMD_CONFIGURE_ADAPTER_MEMORY] == 0 && time_before(jiffies, timeout));
		if (time_after_eq(jiffies, timeout))
			TIMEOUT_MSG(__LINE__);
	}


	/*
	 * configure adapter to receive broadcast messages and wait for response
	 */
	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: sending 82586 configure command\n", dev->name);
	adapter->tx_pcb.command = CMD_CONFIGURE_82586;
	adapter->tx_pcb.data.configure = NO_LOOPBACK | RECV_BROAD;
	adapter->tx_pcb.length = 2;
	adapter->got[CMD_CONFIGURE_82586] = 0;
	if (!send_pcb(dev, &adapter->tx_pcb))
		printk(KERN_ERR "%s: couldn't send 82586 configure command\n", dev->name);
	else {
		unsigned long timeout = jiffies + TIMEOUT;
		while (adapter->got[CMD_CONFIGURE_82586] == 0 && time_before(jiffies, timeout));
		if (time_after_eq(jiffies, timeout))
			TIMEOUT_MSG(__LINE__);
	}

	/* enable burst-mode DMA */
	/* outb(0x1, dev->base_addr + PORT_AUXDMA); */

	/*
	 * queue receive commands to provide buffering
	 */
	prime_rx(dev);
	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: %d receive PCBs active\n", dev->name, adapter->rx_active);

	/*
	 * device is now officially open!
	 */

	netif_start_queue(dev);
	return 0;
}


/******************************************************
 *
 * send a packet to the adapter
 *
 ******************************************************/

static int send_packet(struct net_device *dev, struct sk_buff *skb)
{
	elp_device *adapter = dev->priv;
	unsigned long target;
	unsigned long flags;

	/*
	 * make sure the length is even and no shorter than 60 bytes
	 */
	unsigned int nlen = (((skb->len < 60) ? 60 : skb->len) + 1) & (~1);

	if (test_and_set_bit(0, (void *) &adapter->busy)) {
		if (elp_debug >= 2)
			printk(KERN_DEBUG "%s: transmit blocked\n", dev->name);
		return FALSE;
	}

	adapter->stats.tx_bytes += nlen;

	/*
	 * send the adapter a transmit packet command. Ignore segment and offset
	 * and make sure the length is even
	 */
	adapter->tx_pcb.command = CMD_TRANSMIT_PACKET;
	adapter->tx_pcb.length = sizeof(struct Xmit_pkt);
	adapter->tx_pcb.data.xmit_pkt.buf_ofs
	    = adapter->tx_pcb.data.xmit_pkt.buf_seg = 0;	/* Unused */
	adapter->tx_pcb.data.xmit_pkt.pkt_len = nlen;

	if (!send_pcb(dev, &adapter->tx_pcb)) {
		adapter->busy = 0;
		return FALSE;
	}
	/* if this happens, we die */
	if (test_and_set_bit(0, (void *) &adapter->dmaing))
		printk(KERN_DEBUG "%s: tx: DMA %d in progress\n", dev->name, adapter->current_dma.direction);

	adapter->current_dma.direction = 1;
	adapter->current_dma.start_time = jiffies;

	if ((unsigned long)(skb->data + nlen) >= MAX_DMA_ADDRESS || nlen != skb->len) {
		memcpy(adapter->dma_buffer, skb->data, nlen);
		memset(adapter->dma_buffer+skb->len, 0, nlen-skb->len);
		target = isa_virt_to_bus(adapter->dma_buffer);
	}
	else {
		target = isa_virt_to_bus(skb->data);
	}
	adapter->current_dma.skb = skb;

	flags=claim_dma_lock();
	disable_dma(dev->dma);
	clear_dma_ff(dev->dma);
	set_dma_mode(dev->dma, 0x48);	/* dma memory -> io */
	set_dma_addr(dev->dma, target);
	set_dma_count(dev->dma, nlen);
	outb_control(adapter->hcr_val | DMAE | TCEN, dev);
	enable_dma(dev->dma);
	release_dma_lock(flags);

	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: DMA transfer started\n", dev->name);

	return TRUE;
}

/*
 *	The upper layer thinks we timed out
 */

static void elp_timeout(struct net_device *dev)
{
	elp_device *adapter = dev->priv;
	int stat;

	stat = inb_status(dev->base_addr);
	printk(KERN_WARNING "%s: transmit timed out, lost %s?\n", dev->name, (stat & ACRF) ? "interrupt" : "command");
	if (elp_debug >= 1)
		printk(KERN_DEBUG "%s: status %#02x\n", dev->name, stat);
	dev->trans_start = jiffies;
	adapter->stats.tx_dropped++;
	netif_wake_queue(dev);
}

/******************************************************
 *
 * start the transmitter
 *    return 0 if sent OK, else return 1
 *
 ******************************************************/

static int elp_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	unsigned long flags;
	elp_device *adapter = dev->priv;

	spin_lock_irqsave(&adapter->lock, flags);
	check_3c505_dma(dev);

	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: request to send packet of length %d\n", dev->name, (int) skb->len);

	netif_stop_queue(dev);

	/*
	 * send the packet at skb->data for skb->len
	 */
	if (!send_packet(dev, skb)) {
		if (elp_debug >= 2) {
			printk(KERN_DEBUG "%s: failed to transmit packet\n", dev->name);
		}
		spin_unlock_irqrestore(&adapter->lock, flags);
		return 1;
	}
	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: packet of length %d sent\n", dev->name, (int) skb->len);

	/*
	 * start the transmit timeout
	 */
	dev->trans_start = jiffies;

	prime_rx(dev);
	spin_unlock_irqrestore(&adapter->lock, flags);
	netif_start_queue(dev);
	return 0;
}

/******************************************************
 *
 * return statistics on the board
 *
 ******************************************************/

static struct net_device_stats *elp_get_stats(struct net_device *dev)
{
	elp_device *adapter = (elp_device *) dev->priv;

	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: request for stats\n", dev->name);

	/* If the device is closed, just return the latest stats we have,
	   - we cannot ask from the adapter without interrupts */
	if (!netif_running(dev))
		return &adapter->stats;

	/* send a get statistics command to the board */
	adapter->tx_pcb.command = CMD_NETWORK_STATISTICS;
	adapter->tx_pcb.length = 0;
	adapter->got[CMD_NETWORK_STATISTICS] = 0;
	if (!send_pcb(dev, &adapter->tx_pcb))
		printk(KERN_ERR "%s: couldn't send get statistics command\n", dev->name);
	else {
		unsigned long timeout = jiffies + TIMEOUT;
		while (adapter->got[CMD_NETWORK_STATISTICS] == 0 && time_before(jiffies, timeout));
		if (time_after_eq(jiffies, timeout)) {
			TIMEOUT_MSG(__LINE__);
			return &adapter->stats;
		}
	}

	/* statistics are now up to date */
	return &adapter->stats;
}


static void netdev_get_drvinfo(struct net_device *dev,
			       struct ethtool_drvinfo *info)
{
	strcpy(info->driver, DRV_NAME);
	strcpy(info->version, DRV_VERSION);
	sprintf(info->bus_info, "ISA 0x%lx", dev->base_addr);
}

static u32 netdev_get_msglevel(struct net_device *dev)
{
	return debug;
}

static void netdev_set_msglevel(struct net_device *dev, u32 level)
{
	debug = level;
}

static const struct ethtool_ops netdev_ethtool_ops = {
	.get_drvinfo		= netdev_get_drvinfo,
	.get_msglevel		= netdev_get_msglevel,
	.set_msglevel		= netdev_set_msglevel,
};

/******************************************************
 *
 * close the board
 *
 ******************************************************/

static int elp_close(struct net_device *dev)
{
	elp_device *adapter;

	adapter = dev->priv;

	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: request to close device\n", dev->name);

	netif_stop_queue(dev);

	/* Someone may request the device statistic information even when
	 * the interface is closed. The following will update the statistics
	 * structure in the driver, so we'll be able to give current statistics.
	 */
	(void) elp_get_stats(dev);

	/*
	 * disable interrupts on the board
	 */
	outb_control(0, dev);

	/*
	 * release the IRQ
	 */
	free_irq(dev->irq, dev);

	free_dma(dev->dma);
	free_pages((unsigned long) adapter->dma_buffer, get_order(DMA_BUFFER_SIZE));

	return 0;
}


/************************************************************
 *
 * Set multicast list
 * num_addrs==0: clear mc_list
 * num_addrs==-1: set promiscuous mode
 * num_addrs>0: set mc_list
 *
 ************************************************************/

static void elp_set_mc_list(struct net_device *dev)
{
	elp_device *adapter = (elp_device *) dev->priv;
	struct dev_mc_list *dmi = dev->mc_list;
	int i;
	unsigned long flags;

	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: request to set multicast list\n", dev->name);

	spin_lock_irqsave(&adapter->lock, flags);

	if (!(dev->flags & (IFF_PROMISC | IFF_ALLMULTI))) {
		/* send a "load multicast list" command to the board, max 10 addrs/cmd */
		/* if num_addrs==0 the list will be cleared */
		adapter->tx_pcb.command = CMD_LOAD_MULTICAST_LIST;
		adapter->tx_pcb.length = 6 * dev->mc_count;
		for (i = 0; i < dev->mc_count; i++) {
			memcpy(adapter->tx_pcb.data.multicast[i], dmi->dmi_addr, 6);
			dmi = dmi->next;
		}
		adapter->got[CMD_LOAD_MULTICAST_LIST] = 0;
		if (!send_pcb(dev, &adapter->tx_pcb))
			printk(KERN_ERR "%s: couldn't send set_multicast command\n", dev->name);
		else {
			unsigned long timeout = jiffies + TIMEOUT;
			while (adapter->got[CMD_LOAD_MULTICAST_LIST] == 0 && time_before(jiffies, timeout));
			if (time_after_eq(jiffies, timeout)) {
				TIMEOUT_MSG(__LINE__);
			}
		}
		if (dev->mc_count)
			adapter->tx_pcb.data.configure = NO_LOOPBACK | RECV_BROAD | RECV_MULTI;
		else		/* num_addrs == 0 */
			adapter->tx_pcb.data.configure = NO_LOOPBACK | RECV_BROAD;
	} else
		adapter->tx_pcb.data.configure = NO_LOOPBACK | RECV_PROMISC;
	/*
	 * configure adapter to receive messages (as specified above)
	 * and wait for response
	 */
	if (elp_debug >= 3)
		printk(KERN_DEBUG "%s: sending 82586 configure command\n", dev->name);
	adapter->tx_pcb.command = CMD_CONFIGURE_82586;
	adapter->tx_pcb.length = 2;
	adapter->got[CMD_CONFIGURE_82586] = 0;
	if (!send_pcb(dev, &adapter->tx_pcb))
	{
		spin_unlock_irqrestore(&adapter->lock, flags);
		printk(KERN_ERR "%s: couldn't send 82586 configure command\n", dev->name);
	}
	else {
		unsigned long timeout = jiffies + TIMEOUT;
		spin_unlock_irqrestore(&adapter->lock, flags);
		while (adapter->got[CMD_CONFIGURE_82586] == 0 && time_before(jiffies, timeout));
		if (time_after_eq(jiffies, timeout))
			TIMEOUT_MSG(__LINE__);
	}
}

/************************************************************
 *
 * A couple of tests to see if there's 3C505 or not
 * Called only by elp_autodetect
 ************************************************************/

static int __init elp_sense(struct net_device *dev)
{
	int addr = dev->base_addr;
	const char *name = dev->name;
	byte orig_HSR;

	if (!request_region(addr, ELP_IO_EXTENT, "3c505"))
		return -ENODEV;

	orig_HSR = inb_status(addr);

	if (elp_debug > 0)
		printk(search_msg, name, addr);

	if (orig_HSR == 0xff) {
		if (elp_debug > 0)
			printk(notfound_msg, 1);
		goto out;
	}

	/* Wait for a while; the adapter may still be booting up */
	if (elp_debug > 0)
		printk(stilllooking_msg);

	if (orig_HSR & DIR) {
		/* If HCR.DIR is up, we pull it down. HSR.DIR should follow. */
		outb(0, dev->base_addr + PORT_CONTROL);
		msleep(300);
		if (inb_status(addr) & DIR) {
			if (elp_debug > 0)
				printk(notfound_msg, 2);
			goto out;
		}
	} else {
		/* If HCR.DIR is down, we pull it up. HSR.DIR should follow. */
		outb(DIR, dev->base_addr + PORT_CONTROL);
		msleep(300);
		if (!(inb_status(addr) & DIR)) {
			if (elp_debug > 0)
				printk(notfound_msg, 3);
			goto out;
		}
	}
	/*
	 * It certainly looks like a 3c505.
	 */
	if (elp_debug > 0)
		printk(found_msg);

	return 0;
out:
	release_region(addr, ELP_IO_EXTENT);
	return -ENODEV;
}

/*************************************************************
 *
 * Search through addr_list[] and try to find a 3C505
 * Called only by eplus_probe
 *************************************************************/

static int __init elp_autodetect(struct net_device *dev)
{
	int idx = 0;

	/* if base address set, then only check that address
	   otherwise, run through the table */
	if (dev->base_addr != 0) {	/* dev->base_addr == 0 ==> plain autodetect */
		if (elp_sense(dev) == 0)
			return dev->base_addr;
	} else
		while ((dev->base_addr = addr_list[idx++])) {
			if (elp_sense(dev) == 0)
				return dev->base_addr;
		}

	/* could not find an adapter */
	if (elp_debug > 0)
		printk(couldnot_msg, dev->name);

	return 0;		/* Because of this, the layer above will return -ENODEV */
}


/******************************************************
 *
 * probe for an Etherlink Plus board at the specified address
 *
 ******************************************************/

/* There are three situations we need to be able to detect here:

 *  a) the card is idle
 *  b) the card is still booting up
 *  c) the card is stuck in a strange state (some DOS drivers do this)
 *
 * In case (a), all is well.  In case (b), we wait 10 seconds to see if the
 * card finishes booting, and carry on if so.  In case (c), we do a hard reset,
 * loop round, and hope for the best.
 *
 * This is all very unpleasant, but hopefully avoids the problems with the old
 * probe code (which had a 15-second delay if the card was idle, and didn't
 * work at all if it was in a weird state).
 */

static int __init elplus_setup(struct net_device *dev)
{
	elp_device *adapter = dev->priv;
	int i, tries, tries1, okay;
	unsigned long timeout;
	unsigned long cookie = 0;
	int err = -ENODEV;

	SET_MODULE_OWNER(dev);

	/*
	 *  setup adapter structure
	 */

	dev->base_addr = elp_autodetect(dev);
	if (!dev->base_addr)
		return -ENODEV;

	adapter->send_pcb_semaphore = 0;

	for (tries1 = 0; tries1 < 3; tries1++) {
		outb_control((adapter->hcr_val | CMDE) & ~DIR, dev);
		/* First try to write just one byte, to see if the card is
		 * responding at all normally.
		 */
		timeout = jiffies + 5*HZ/100;
		okay = 0;
		while (time_before(jiffies, timeout) && !(inb_status(dev->base_addr) & HCRE));
		if ((inb_status(dev->base_addr) & HCRE)) {
			outb_command(0, dev->base_addr);	/* send a spurious byte */
			timeout = jiffies + 5*HZ/100;
			while (time_before(jiffies, timeout) && !(inb_status(dev->base_addr) & HCRE));
			if (inb_status(dev->base_addr) & HCRE)
				okay = 1;
		}
		if (!okay) {
			/* Nope, it's ignoring the command register.  This means that
			 * either it's still booting up, or it's died.
			 */
			printk(KERN_ERR "%s: command register wouldn't drain, ", dev->name);
			if ((inb_status(dev->base_addr) & 7) == 3) {
				/* If the adapter status is 3, it *could* still be booting.
				 * Give it the benefit of the doubt for 10 seconds.
				 */
				printk("assuming 3c505 still starting\n");
				timeout = jiffies + 10*HZ;
				while (time_before(jiffies, timeout) && (inb_status(dev->base_addr) & 7));
				if (inb_status(dev->base_addr) & 7) {
					printk(KERN_ERR "%s: 3c505 failed to start\n", dev->name);
				} else {
					okay = 1;  /* It started */
				}
			} else {
				/* Otherwise, it must just be in a strange
				 * state.  We probably need to kick it.
				 */
				printk("3c505 is sulking\n");
			}
		}
		for (tries = 0; tries < 5 && okay; tries++) {

			/*
			 * Try to set the Ethernet address, to make sure that the board
			 * is working.
			 */
			adapter->tx_pcb.command = CMD_STATION_ADDRESS;
			adapter->tx_pcb.length = 0;
			cookie = probe_irq_on();
			if (!send_pcb(dev, &adapter->tx_pcb)) {
				printk(KERN_ERR "%s: could not send first PCB\n", dev->name);
				probe_irq_off(cookie);
				continue;
			}
			if (!receive_pcb(dev, &adapter->rx_pcb)) {
				printk(KERN_ERR "%s: could not read first PCB\n", dev->name);
				probe_irq_off(cookie);
				continue;
			}
			if ((adapter->rx_pcb.command != CMD_ADDRESS_RESPONSE) ||
			    (adapter->rx_pcb.length != 6)) {
				printk(KERN_ERR "%s: first PCB wrong (%d, %d)\n", dev->name, adapter->rx_pcb.command, adapter->rx_pcb.length);
				probe_irq_off(cookie);
				continue;
			}
			goto okay;
		}
		/* It's broken.  Do a hard reset to re-initialise the board,
		 * and try again.
		 */
		printk(KERN_INFO "%s: resetting adapter\n", dev->name);
		outb_control(adapter->hcr_val | FLSH | ATTN, dev);
		outb_control(adapter->hcr_val & ~(FLSH | ATTN), dev);
	}
	printk(KERN_ERR "%s: failed to initialise 3c505\n", dev->name);
	goto out;

      okay:
	if (dev->irq) {		/* Is there a preset IRQ? */
		int rpt = probe_irq_off(cookie);
		if (dev->irq != rpt) {
			printk(KERN_WARNING "%s: warning, irq %d configured but %d detected\n", dev->name, dev->irq, rpt);
		}
		/* if dev->irq == probe_irq_off(cookie), all is well */
	} else		       /* No preset IRQ; just use what we can detect */
		dev->irq = probe_irq_off(cookie);
	switch (dev->irq) {    /* Legal, sane? */
	case 0:
		printk(KERN_ERR "%s: IRQ probe failed: check 3c505 jumpers.\n",
		       dev->name);
		goto out;
	case 1:
	case 6:
	case 8:
	case 13:
		printk(KERN_ERR "%s: Impossible IRQ %d reported by probe_irq_off().\n",
		       dev->name, dev->irq);
		       goto out;
	}
	/*
	 *  Now we have the IRQ number so we can disable the interrupts from
	 *  the board until the board is opened.
	 */
	outb_control(adapter->hcr_val & ~CMDE, dev);

	/*
	 * copy Ethernet address into structure
	 */
	for (i = 0; i < 6; i++)
		dev->dev_addr[i] = adapter->rx_pcb.data.eth_addr[i];

	/* find a DMA channel */
	if (!dev->dma) {
		if (dev->mem_start) {
			dev->dma = dev->mem_start & 7;
		}
		else {
			printk(KERN_WARNING "%s: warning, DMA channel not specified, using default\n", dev->name);
			dev->dma = ELP_DMA;
		}
	}

	/*
	 * print remainder of startup message
	 */
	printk(KERN_INFO "%s: 3c505 at %#lx, irq %d, dma %d, ",
	       dev->name, dev->base_addr, dev->irq, dev->dma);
	printk("addr %02x:%02x:%02x:%02x:%02x:%02x, ",
	       dev->dev_addr[0], dev->dev_addr[1], dev->dev_addr[2],
	       dev->dev_addr[3], dev->dev_addr[4], dev->dev_addr[5]);

	/*
	 * read more information from the adapter
	 */

	adapter->tx_pcb.command = CMD_ADAPTER_INFO;
	adapter->tx_pcb.length = 0;
	if (!send_pcb(dev, &adapter->tx_pcb) ||
	    !receive_pcb(dev, &adapter->rx_pcb) ||
	    (adapter->rx_pcb.command != CMD_ADAPTER_INFO_RESPONSE) ||
	    (adapter->rx_pcb.length != 10)) {
		printk("not responding to second PCB\n");
	}
	printk("rev %d.%d, %dk\n", adapter->rx_pcb.data.info.major_vers, adapter->rx_pcb.data.info.minor_vers, adapter->rx_pcb.data.info.RAM_sz);

	/*
	 * reconfigure the adapter memory to better suit our purposes
	 */
	adapter->tx_pcb.command = CMD_CONFIGURE_ADAPTER_MEMORY;
	adapter->tx_pcb.length = 12;
	adapter->tx_pcb.data.memconf.cmd_q = 8;
	adapter->tx_pcb.data.memconf.rcv_q = 8;
	adapter->tx_pcb.data.memconf.mcast = 10;
	adapter->tx_pcb.data.memconf.frame = 10;
	adapter->tx_pcb.data.memconf.rcv_b = 10;
	adapter->tx_pcb.data.memconf.progs = 0;
	if (!send_pcb(dev, &adapter->tx_pcb) ||
	    !receive_pcb(dev, &adapter->rx_pcb) ||
	    (adapter->rx_pcb.command != CMD_CONFIGURE_ADAPTER_RESPONSE) ||
	    (adapter->rx_pcb.length != 2)) {
		printk(KERN_ERR "%s: could not configure adapter memory\n", dev->name);
	}
	if (adapter->rx_pcb.data.configure) {
		printk(KERN_ERR "%s: adapter configuration failed\n", dev->name);
	}

	dev->open = elp_open;				/* local */
	dev->stop = elp_close;				/* local */
	dev->get_stats = elp_get_stats;			/* local */
	dev->hard_start_xmit = elp_start_xmit;		/* local */
	dev->tx_timeout = elp_timeout;			/* local */
	dev->watchdog_timeo = 10*HZ;
	dev->set_multicast_list = elp_set_mc_list;	/* local */
	dev->ethtool_ops = &netdev_ethtool_ops;		/* local */

	memset(&(adapter->stats), 0, sizeof(struct net_device_stats));
	dev->mem_start = dev->mem_end = 0;

	err = register_netdev(dev);
	if (err)
		goto out;

	return 0;
out:
	release_region(dev->base_addr, ELP_IO_EXTENT);
	return err;
}

#ifndef MODULE
struct net_device * __init elplus_probe(int unit)
{
	struct net_device *dev = alloc_etherdev(sizeof(elp_device));
	int err;
	if (!dev)
		return ERR_PTR(-ENOMEM);

	sprintf(dev->name, "eth%d", unit);
	netdev_boot_setup_check(dev);

	err = elplus_setup(dev);
	if (err) {
		free_netdev(dev);
		return ERR_PTR(err);
	}
	return dev;
}

#else
static struct net_device *dev_3c505[ELP_MAX_CARDS];
static int io[ELP_MAX_CARDS];
static int irq[ELP_MAX_CARDS];
static int dma[ELP_MAX_CARDS];
module_param_array(io, int, NULL, 0);
module_param_array(irq, int, NULL, 0);
module_param_array(dma, int, NULL, 0);
MODULE_PARM_DESC(io, "EtherLink Plus I/O base address(es)");
MODULE_PARM_DESC(irq, "EtherLink Plus IRQ number(s) (assigned)");
MODULE_PARM_DESC(dma, "EtherLink Plus DMA channel(s)");

int __init init_module(void)
{
	int this_dev, found = 0;

	for (this_dev = 0; this_dev < ELP_MAX_CARDS; this_dev++) {
		struct net_device *dev = alloc_etherdev(sizeof(elp_device));
		if (!dev)
			break;

		dev->irq = irq[this_dev];
		dev->base_addr = io[this_dev];
		if (dma[this_dev]) {
			dev->dma = dma[this_dev];
		} else {
			dev->dma = ELP_DMA;
			printk(KERN_WARNING "3c505.c: warning, using default DMA channel,\n");
		}
		if (io[this_dev] == 0) {
			if (this_dev) {
				free_netdev(dev);
				break;
			}
			printk(KERN_NOTICE "3c505.c: module autoprobe not recommended, give io=xx.\n");
		}
		if (elplus_setup(dev) != 0) {
			printk(KERN_WARNING "3c505.c: Failed to register card at 0x%x.\n", io[this_dev]);
			free_netdev(dev);
			break;
		}
		dev_3c505[this_dev] = dev;
		found++;
	}
	if (!found)
		return -ENODEV;
	return 0;
}

void __exit cleanup_module(void)
{
	int this_dev;

	for (this_dev = 0; this_dev < ELP_MAX_CARDS; this_dev++) {
		struct net_device *dev = dev_3c505[this_dev];
		if (dev) {
			unregister_netdev(dev);
			release_region(dev->base_addr, ELP_IO_EXTENT);
			free_netdev(dev);
		}
	}
}

#endif				/* MODULE */
MODULE_LICENSE("GPL");