1/* 3c501.c: A 3Com 3c501 Ethernet driver for Linux. */
2/*
3    Written 1992,1993,1994  Donald Becker
4
5    Copyright 1993 United States Government as represented by the
6    Director, National Security Agency.  This software may be used and
7    distributed according to the terms of the GNU General Public License,
8    incorporated herein by reference.
9
10    This is a device driver for the 3Com Etherlink 3c501.
11    Do not purchase this card, even as a joke.  It's performance is horrible,
12    and it breaks in many ways.
13
14    The original author may be reached as becker@scyld.com, or C/O
15	Scyld Computing Corporation
16	410 Severn Ave., Suite 210
17	Annapolis MD 21403
18
19    Fixed (again!) the missing interrupt locking on TX/RX shifting.
20	Alan Cox <alan@lxorguk.ukuu.org.uk>
21
22    Removed calls to init_etherdev since they are no longer needed, and
23    cleaned up modularization just a bit. The driver still allows only
24    the default address for cards when loaded as a module, but that's
25    really less braindead than anyone using a 3c501 board. :)
26		    19950208 (invid@msen.com)
27
28    Added traps for interrupts hitting the window as we clear and TX load
29    the board. Now getting 150K/second FTP with a 3c501 card. Still playing
30    with a TX-TX optimisation to see if we can touch 180-200K/second as seems
31    theoretically maximum.
32		19950402 Alan Cox <alan@lxorguk.ukuu.org.uk>
33
34    Cleaned up for 2.3.x because we broke SMP now.
35		20000208 Alan Cox <alan@lxorguk.ukuu.org.uk>
36
37    Check up pass for 2.5. Nothing significant changed
38		20021009 Alan Cox <alan@lxorguk.ukuu.org.uk>
39
40    Fixed zero fill corner case
41		20030104 Alan Cox <alan@lxorguk.ukuu.org.uk>
42
43
44   For the avoidance of doubt the "preferred form" of this code is one which
45   is in an open non patent encumbered format. Where cryptographic key signing
46   forms part of the process of creating an executable the information
47   including keys needed to generate an equivalently functional executable
48   are deemed to be part of the source code.
49
50*/
51
52
53/**
54 * DOC: 3c501 Card Notes
55 *
56 *  Some notes on this thing if you have to hack it.  [Alan]
57 *
58 *  Some documentation is available from 3Com. Due to the boards age
59 *  standard responses when you ask for this will range from 'be serious'
60 *  to 'give it to a museum'. The documentation is incomplete and mostly
61 *  of historical interest anyway.
62 *
63 *  The basic system is a single buffer which can be used to receive or
64 *  transmit a packet. A third command mode exists when you are setting
65 *  things up.
66 *
67 *  If it's transmitting it's not receiving and vice versa. In fact the
68 *  time to get the board back into useful state after an operation is
69 *  quite large.
70 *
71 *  The driver works by keeping the board in receive mode waiting for a
72 *  packet to arrive. When one arrives it is copied out of the buffer
73 *  and delivered to the kernel. The card is reloaded and off we go.
74 *
75 *  When transmitting lp->txing is set and the card is reset (from
76 *  receive mode) [possibly losing a packet just received] to command
77 *  mode. A packet is loaded and transmit mode triggered. The interrupt
78 *  handler runs different code for transmit interrupts and can handle
79 *  returning to receive mode or retransmissions (yes you have to help
80 *  out with those too).
81 *
82 * DOC: Problems
83 *
84 *  There are a wide variety of undocumented error returns from the card
85 *  and you basically have to kick the board and pray if they turn up. Most
86 *  only occur under extreme load or if you do something the board doesn't
87 *  like (eg touching a register at the wrong time).
88 *
89 *  The driver is less efficient than it could be. It switches through
90 *  receive mode even if more transmits are queued. If this worries you buy
91 *  a real Ethernet card.
92 *
93 *  The combination of slow receive restart and no real multicast
94 *  filter makes the board unusable with a kernel compiled for IP
95 *  multicasting in a real multicast environment. That's down to the board,
96 *  but even with no multicast programs running a multicast IP kernel is
97 *  in group 224.0.0.1 and you will therefore be listening to all multicasts.
98 *  One nv conference running over that Ethernet and you can give up.
99 *
100 */
101
102#define DRV_NAME	"3c501"
103#define DRV_VERSION	"2002/10/09"
104
105
106static const char version[] =
107	DRV_NAME ".c: " DRV_VERSION " Alan Cox (alan@lxorguk.ukuu.org.uk).\n";
108
109/*
110 *	Braindamage remaining:
111 *	The 3c501 board.
112 */
113
114#include <linux/module.h>
115
116#include <linux/kernel.h>
117#include <linux/fcntl.h>
118#include <linux/ioport.h>
119#include <linux/interrupt.h>
120#include <linux/string.h>
121#include <linux/errno.h>
122#include <linux/spinlock.h>
123#include <linux/ethtool.h>
124#include <linux/delay.h>
125#include <linux/bitops.h>
126
127#include <asm/uaccess.h>
128#include <asm/io.h>
129
130#include <linux/netdevice.h>
131#include <linux/etherdevice.h>
132#include <linux/skbuff.h>
133#include <linux/init.h>
134
135#include "3c501.h"
136
137/*
138 *	The boilerplate probe code.
139 */
140
141static int io = 0x280;
142static int irq = 5;
143static int mem_start;
144
145/**
146 * el1_probe:		-	probe for a 3c501
147 * @dev: The device structure passed in to probe.
148 *
149 * This can be called from two places. The network layer will probe using
150 * a device structure passed in with the probe information completed. For a
151 * modular driver we use #init_module to fill in our own structure and probe
152 * for it.
153 *
154 * Returns 0 on success. ENXIO if asked not to probe and ENODEV if asked to
155 * probe and failing to find anything.
156 */
157
158struct net_device * __init el1_probe(int unit)
159{
160	struct net_device *dev = alloc_etherdev(sizeof(struct net_local));
161	static const unsigned ports[] = { 0x280, 0x300, 0};
162	const unsigned *port;
163	int err = 0;
164
165	if (!dev)
166		return ERR_PTR(-ENOMEM);
167
168	if (unit >= 0) {
169		sprintf(dev->name, "eth%d", unit);
170		netdev_boot_setup_check(dev);
171		io = dev->base_addr;
172		irq = dev->irq;
173		mem_start = dev->mem_start & 7;
174	}
175
176	if (io > 0x1ff) {	/* Check a single specified location. */
177		err = el1_probe1(dev, io);
178	} else if (io != 0) {
179		err = -ENXIO;		/* Don't probe at all. */
180	} else {
181		for (port = ports; *port && el1_probe1(dev, *port); port++)
182			;
183		if (!*port)
184			err = -ENODEV;
185	}
186	if (err)
187		goto out;
188	err = register_netdev(dev);
189	if (err)
190		goto out1;
191	return dev;
192out1:
193	release_region(dev->base_addr, EL1_IO_EXTENT);
194out:
195	free_netdev(dev);
196	return ERR_PTR(err);
197}
198
199static const struct net_device_ops el_netdev_ops = {
200	.ndo_open		= el_open,
201	.ndo_stop		= el1_close,
202	.ndo_start_xmit 	= el_start_xmit,
203	.ndo_tx_timeout		= el_timeout,
204	.ndo_set_rx_mode	= set_multicast_list,
205	.ndo_change_mtu		= eth_change_mtu,
206	.ndo_set_mac_address 	= eth_mac_addr,
207	.ndo_validate_addr	= eth_validate_addr,
208};
209
210/**
211 *	el1_probe1:
212 *	@dev: The device structure to use
213 *	@ioaddr: An I/O address to probe at.
214 *
215 *	The actual probe. This is iterated over by #el1_probe in order to
216 *	check all the applicable device locations.
217 *
218 *	Returns 0 for a success, in which case the device is activated,
219 *	EAGAIN if the IRQ is in use by another driver, and ENODEV if the
220 *	board cannot be found.
221 */
222
223static int __init el1_probe1(struct net_device *dev, int ioaddr)
224{
225	struct net_local *lp;
226	const char *mname;		/* Vendor name */
227	unsigned char station_addr[6];
228	int autoirq = 0;
229	int i;
230
231	/*
232	 *	Reserve I/O resource for exclusive use by this driver
233	 */
234
235	if (!request_region(ioaddr, EL1_IO_EXTENT, DRV_NAME))
236		return -ENODEV;
237
238	/*
239	 *	Read the station address PROM data from the special port.
240	 */
241
242	for (i = 0; i < 6; i++) {
243		outw(i, ioaddr + EL1_DATAPTR);
244		station_addr[i] = inb(ioaddr + EL1_SAPROM);
245	}
246	/*
247	 *	Check the first three octets of the S.A. for 3Com's prefix, or
248	 *	for the Sager NP943 prefix.
249	 */
250
251	if (station_addr[0] == 0x02 && station_addr[1] == 0x60 &&
252	    station_addr[2] == 0x8c)
253		mname = "3c501";
254	else if (station_addr[0] == 0x00 && station_addr[1] == 0x80 &&
255		 station_addr[2] == 0xC8)
256		mname = "NP943";
257	else {
258		release_region(ioaddr, EL1_IO_EXTENT);
259		return -ENODEV;
260	}
261
262	/*
263	 *	We auto-IRQ by shutting off the interrupt line and letting it
264	 *	float high.
265	 */
266
267	dev->irq = irq;
268
269	if (dev->irq < 2) {
270		unsigned long irq_mask;
271
272		irq_mask = probe_irq_on();
273		inb(RX_STATUS);		/* Clear pending interrupts. */
274		inb(TX_STATUS);
275		outb(AX_LOOP + 1, AX_CMD);
276
277		outb(0x00, AX_CMD);
278
279		mdelay(20);
280		autoirq = probe_irq_off(irq_mask);
281
282		if (autoirq == 0) {
283			pr_warning("%s probe at %#x failed to detect IRQ line.\n",
284				mname, ioaddr);
285			release_region(ioaddr, EL1_IO_EXTENT);
286			return -EAGAIN;
287		}
288	}
289
290	outb(AX_RESET+AX_LOOP, AX_CMD);			/* Loopback mode. */
291	dev->base_addr = ioaddr;
292	memcpy(dev->dev_addr, station_addr, ETH_ALEN);
293
294	if (mem_start & 0xf)
295		el_debug = mem_start & 0x7;
296	if (autoirq)
297		dev->irq = autoirq;
298
299	pr_info("%s: %s EtherLink at %#lx, using %sIRQ %d.\n",
300			dev->name, mname, dev->base_addr,
301			autoirq ? "auto":"assigned ", dev->irq);
302
303#ifdef CONFIG_IP_MULTICAST
304	pr_warning("WARNING: Use of the 3c501 in a multicast kernel is NOT recommended.\n");
305#endif
306
307	if (el_debug)
308		pr_debug("%s", version);
309
310	lp = netdev_priv(dev);
311	memset(lp, 0, sizeof(struct net_local));
312	spin_lock_init(&lp->lock);
313
314	/*
315	 *	The EL1-specific entries in the device structure.
316	 */
317
318	dev->netdev_ops = &el_netdev_ops;
319	dev->watchdog_timeo = HZ;
320	dev->ethtool_ops = &netdev_ethtool_ops;
321	return 0;
322}
323
324/**
325 *	el1_open:
326 *	@dev: device that is being opened
327 *
328 *	When an ifconfig is issued which changes the device flags to include
329 *	IFF_UP this function is called. It is only called when the change
330 *	occurs, not when the interface remains up. #el1_close will be called
331 *	when it goes down.
332 *
333 *	Returns 0 for a successful open, or -EAGAIN if someone has run off
334 *	with our interrupt line.
335 */
336
337static int el_open(struct net_device *dev)
338{
339	int retval;
340	int ioaddr = dev->base_addr;
341	struct net_local *lp = netdev_priv(dev);
342	unsigned long flags;
343
344	if (el_debug > 2)
345		pr_debug("%s: Doing el_open()...\n", dev->name);
346
347	retval = request_irq(dev->irq, el_interrupt, 0, dev->name, dev);
348	if (retval)
349		return retval;
350
351	spin_lock_irqsave(&lp->lock, flags);
352	el_reset(dev);
353	spin_unlock_irqrestore(&lp->lock, flags);
354
355	lp->txing = 0;		/* Board in RX mode */
356	outb(AX_RX, AX_CMD);	/* Aux control, irq and receive enabled */
357	netif_start_queue(dev);
358	return 0;
359}
360
361/**
362 * el_timeout:
363 * @dev: The 3c501 card that has timed out
364 *
365 * Attempt to restart the board. This is basically a mixture of extreme
366 * violence and prayer
367 *
368 */
369
370static void el_timeout(struct net_device *dev)
371{
372	struct net_local *lp = netdev_priv(dev);
373	int ioaddr = dev->base_addr;
374
375	if (el_debug)
376		pr_debug("%s: transmit timed out, txsr %#2x axsr=%02x rxsr=%02x.\n",
377			dev->name, inb(TX_STATUS),
378			inb(AX_STATUS), inb(RX_STATUS));
379	dev->stats.tx_errors++;
380	outb(TX_NORM, TX_CMD);
381	outb(RX_NORM, RX_CMD);
382	outb(AX_OFF, AX_CMD);	/* Just trigger a false interrupt. */
383	outb(AX_RX, AX_CMD);	/* Aux control, irq and receive enabled */
384	lp->txing = 0;		/* Ripped back in to RX */
385	netif_wake_queue(dev);
386}
387
388
389/**
390 * el_start_xmit:
391 * @skb: The packet that is queued to be sent
392 * @dev: The 3c501 card we want to throw it down
393 *
394 * Attempt to send a packet to a 3c501 card. There are some interesting
395 * catches here because the 3c501 is an extremely old and therefore
396 * stupid piece of technology.
397 *
398 * If we are handling an interrupt on the other CPU we cannot load a packet
399 * as we may still be attempting to retrieve the last RX packet buffer.
400 *
401 * When a transmit times out we dump the card into control mode and just
402 * start again. It happens enough that it isn't worth logging.
403 *
404 * We avoid holding the spin locks when doing the packet load to the board.
405 * The device is very slow, and its DMA mode is even slower. If we held the
406 * lock while loading 1500 bytes onto the controller we would drop a lot of
407 * serial port characters. This requires we do extra locking, but we have
408 * no real choice.
409 */
410
411static netdev_tx_t el_start_xmit(struct sk_buff *skb, struct net_device *dev)
412{
413	struct net_local *lp = netdev_priv(dev);
414	int ioaddr = dev->base_addr;
415	unsigned long flags;
416
417	/*
418	 *	Avoid incoming interrupts between us flipping txing and flipping
419	 *	mode as the driver assumes txing is a faithful indicator of card
420	 *	state
421	 */
422
423	spin_lock_irqsave(&lp->lock, flags);
424
425	/*
426	 *	Avoid timer-based retransmission conflicts.
427	 */
428
429	netif_stop_queue(dev);
430
431	do {
432		int len = skb->len;
433		int pad = 0;
434		int gp_start;
435		unsigned char *buf = skb->data;
436
437		if (len < ETH_ZLEN)
438			pad = ETH_ZLEN - len;
439
440		gp_start = 0x800 - (len + pad);
441
442		lp->tx_pkt_start = gp_start;
443		lp->collisions = 0;
444
445		dev->stats.tx_bytes += skb->len;
446
447		/*
448		 *	Command mode with status cleared should [in theory]
449		 *	mean no more interrupts can be pending on the card.
450		 */
451
452		outb_p(AX_SYS, AX_CMD);
453		inb_p(RX_STATUS);
454		inb_p(TX_STATUS);
455
456		lp->loading = 1;
457		lp->txing = 1;
458
459		/*
460		 *	Turn interrupts back on while we spend a pleasant
461		 *	afternoon loading bytes into the board
462		 */
463
464		spin_unlock_irqrestore(&lp->lock, flags);
465
466		/* Set rx packet area to 0. */
467		outw(0x00, RX_BUF_CLR);
468		/* aim - packet will be loaded into buffer start */
469		outw(gp_start, GP_LOW);
470		/* load buffer (usual thing each byte increments the pointer) */
471		outsb(DATAPORT, buf, len);
472		if (pad) {
473			while (pad--)		/* Zero fill buffer tail */
474				outb(0, DATAPORT);
475		}
476		/* the board reuses the same register */
477		outw(gp_start, GP_LOW);
478
479		if (lp->loading != 2) {
480			/* fire ... Trigger xmit.  */
481			outb(AX_XMIT, AX_CMD);
482			lp->loading = 0;
483			if (el_debug > 2)
484				pr_debug(" queued xmit.\n");
485			dev_kfree_skb(skb);
486			return NETDEV_TX_OK;
487		}
488		/* A receive upset our load, despite our best efforts */
489		if (el_debug > 2)
490			pr_debug("%s: burped during tx load.\n", dev->name);
491		spin_lock_irqsave(&lp->lock, flags);
492	} while (1);
493}
494
495/**
496 * el_interrupt:
497 * @irq: Interrupt number
498 * @dev_id: The 3c501 that burped
499 *
500 * Handle the ether interface interrupts. The 3c501 needs a lot more
501 * hand holding than most cards. In particular we get a transmit interrupt
502 * with a collision error because the board firmware isn't capable of rewinding
503 * its own transmit buffer pointers. It can however count to 16 for us.
504 *
505 * On the receive side the card is also very dumb. It has no buffering to
506 * speak of. We simply pull the packet out of its PIO buffer (which is slow)
507 * and queue it for the kernel. Then we reset the card for the next packet.
508 *
509 * We sometimes get surprise interrupts late both because the SMP IRQ delivery
510 * is message passing and because the card sometimes seems to deliver late. I
511 * think if it is part way through a receive and the mode is changed it carries
512 * on receiving and sends us an interrupt. We have to band aid all these cases
513 * to get a sensible 150kBytes/second performance. Even then you want a small
514 * TCP window.
515 */
516
517static irqreturn_t el_interrupt(int irq, void *dev_id)
518{
519	struct net_device *dev = dev_id;
520	struct net_local *lp;
521	int ioaddr;
522	int axsr;			/* Aux. status reg. */
523
524	ioaddr = dev->base_addr;
525	lp = netdev_priv(dev);
526
527	spin_lock(&lp->lock);
528
529	/*
530	 *	What happened ?
531	 */
532
533	axsr = inb(AX_STATUS);
534
535	/*
536	 *	Log it
537	 */
538
539	if (el_debug > 3)
540		pr_debug("%s: el_interrupt() aux=%#02x\n", dev->name, axsr);
541
542	if (lp->loading == 1 && !lp->txing)
543		pr_warning("%s: Inconsistent state loading while not in tx\n",
544			dev->name);
545
546	if (lp->txing) {
547		/*
548		 *	Board in transmit mode. May be loading. If we are
549		 *	loading we shouldn't have got this.
550		 */
551		int txsr = inb(TX_STATUS);
552
553		if (lp->loading == 1) {
554			if (el_debug > 2)
555				pr_debug("%s: Interrupt while loading [txsr=%02x gp=%04x rp=%04x]\n",
556					dev->name, txsr, inw(GP_LOW), inw(RX_LOW));
557
558			/* Force a reload */
559			lp->loading = 2;
560			spin_unlock(&lp->lock);
561			goto out;
562		}
563		if (el_debug > 6)
564			pr_debug("%s: txsr=%02x gp=%04x rp=%04x\n", dev->name,
565					txsr, inw(GP_LOW), inw(RX_LOW));
566
567		if ((axsr & 0x80) && (txsr & TX_READY) == 0) {
568			/*
569			 *	FIXME: is there a logic to whether to keep
570			 *	on trying or reset immediately ?
571			 */
572			if (el_debug > 1)
573				pr_debug("%s: Unusual interrupt during Tx, txsr=%02x axsr=%02x gp=%03x rp=%03x.\n",
574					dev->name, txsr, axsr,
575					inw(ioaddr + EL1_DATAPTR),
576					inw(ioaddr + EL1_RXPTR));
577			lp->txing = 0;
578			netif_wake_queue(dev);
579		} else if (txsr & TX_16COLLISIONS) {
580			/*
581			 *	Timed out
582			 */
583			if (el_debug)
584				pr_debug("%s: Transmit failed 16 times, Ethernet jammed?\n", dev->name);
585			outb(AX_SYS, AX_CMD);
586			lp->txing = 0;
587			dev->stats.tx_aborted_errors++;
588			netif_wake_queue(dev);
589		} else if (txsr & TX_COLLISION) {
590			/*
591			 *	Retrigger xmit.
592			 */
593
594			if (el_debug > 6)
595				pr_debug("%s: retransmitting after a collision.\n", dev->name);
596			/*
597			 *	Poor little chip can't reset its own start
598			 *	pointer
599			 */
600
601			outb(AX_SYS, AX_CMD);
602			outw(lp->tx_pkt_start, GP_LOW);
603			outb(AX_XMIT, AX_CMD);
604			dev->stats.collisions++;
605			spin_unlock(&lp->lock);
606			goto out;
607		} else {
608			/*
609			 *	It worked.. we will now fall through and receive
610			 */
611			dev->stats.tx_packets++;
612			if (el_debug > 6)
613				pr_debug("%s: Tx succeeded %s\n", dev->name,
614					(txsr & TX_RDY) ? "." : "but tx is busy!");
615			/*
616			 *	This is safe the interrupt is atomic WRT itself.
617			 */
618			lp->txing = 0;
619			/* In case more to transmit */
620			netif_wake_queue(dev);
621		}
622	} else {
623		/*
624		 *	In receive mode.
625		 */
626
627		int rxsr = inb(RX_STATUS);
628		if (el_debug > 5)
629			pr_debug("%s: rxsr=%02x txsr=%02x rp=%04x\n",
630				dev->name, rxsr, inb(TX_STATUS), inw(RX_LOW));
631		/*
632		 *	Just reading rx_status fixes most errors.
633		 */
634		if (rxsr & RX_MISSED)
635			dev->stats.rx_missed_errors++;
636		else if (rxsr & RX_RUNT) {
637			/* Handled to avoid board lock-up. */
638			dev->stats.rx_length_errors++;
639			if (el_debug > 5)
640				pr_debug("%s: runt.\n", dev->name);
641		} else if (rxsr & RX_GOOD) {
642			/*
643			 *	Receive worked.
644			 */
645			el_receive(dev);
646		} else {
647			/*
648			 *	Nothing?  Something is broken!
649			 */
650			if (el_debug > 2)
651				pr_debug("%s: No packet seen, rxsr=%02x **resetting 3c501***\n",
652					dev->name, rxsr);
653			el_reset(dev);
654		}
655	}
656
657	/*
658	 *	Move into receive mode
659	 */
660
661	outb(AX_RX, AX_CMD);
662	outw(0x00, RX_BUF_CLR);
663	inb(RX_STATUS);		/* Be certain that interrupts are cleared. */
664	inb(TX_STATUS);
665	spin_unlock(&lp->lock);
666out:
667	return IRQ_HANDLED;
668}
669
670
671/**
672 * el_receive:
673 * @dev: Device to pull the packets from
674 *
675 * We have a good packet. Well, not really "good", just mostly not broken.
676 * We must check everything to see if it is good. In particular we occasionally
677 * get wild packet sizes from the card. If the packet seems sane we PIO it
678 * off the card and queue it for the protocol layers.
679 */
680
681static void el_receive(struct net_device *dev)
682{
683	int ioaddr = dev->base_addr;
684	int pkt_len;
685	struct sk_buff *skb;
686
687	pkt_len = inw(RX_LOW);
688
689	if (el_debug > 4)
690		pr_debug(" el_receive %d.\n", pkt_len);
691
692	if (pkt_len < 60 || pkt_len > 1536) {
693		if (el_debug)
694			pr_debug("%s: bogus packet, length=%d\n",
695						dev->name, pkt_len);
696		dev->stats.rx_over_errors++;
697		return;
698	}
699
700	/*
701	 *	Command mode so we can empty the buffer
702	 */
703
704	outb(AX_SYS, AX_CMD);
705	skb = netdev_alloc_skb(dev, pkt_len + 2);
706
707	/*
708	 *	Start of frame
709	 */
710
711	outw(0x00, GP_LOW);
712	if (skb == NULL) {
713		pr_info("%s: Memory squeeze, dropping packet.\n", dev->name);
714		dev->stats.rx_dropped++;
715		return;
716	} else {
717		skb_reserve(skb, 2);	/* Force 16 byte alignment */
718		/*
719		 *	The read increments through the bytes. The interrupt
720		 *	handler will fix the pointer when it returns to
721		 *	receive mode.
722		 */
723		insb(DATAPORT, skb_put(skb, pkt_len), pkt_len);
724		skb->protocol = eth_type_trans(skb, dev);
725		netif_rx(skb);
726		dev->stats.rx_packets++;
727		dev->stats.rx_bytes += pkt_len;
728	}
729}
730
731/**
732 * el_reset: Reset a 3c501 card
733 * @dev: The 3c501 card about to get zapped
734 *
735 * Even resetting a 3c501 isn't simple. When you activate reset it loses all
736 * its configuration. You must hold the lock when doing this. The function
737 * cannot take the lock itself as it is callable from the irq handler.
738 */
739
740static void  el_reset(struct net_device *dev)
741{
742	struct net_local *lp = netdev_priv(dev);
743	int ioaddr = dev->base_addr;
744
745	if (el_debug > 2)
746		pr_info("3c501 reset...\n");
747	outb(AX_RESET, AX_CMD);		/* Reset the chip */
748	/* Aux control, irq and loopback enabled */
749	outb(AX_LOOP, AX_CMD);
750	{
751		int i;
752		for (i = 0; i < 6; i++)	/* Set the station address. */
753			outb(dev->dev_addr[i], ioaddr + i);
754	}
755
756	outw(0, RX_BUF_CLR);		/* Set rx packet area to 0. */
757	outb(TX_NORM, TX_CMD);		/* tx irq on done, collision */
758	outb(RX_NORM, RX_CMD);		/* Set Rx commands. */
759	inb(RX_STATUS);			/* Clear status. */
760	inb(TX_STATUS);
761	lp->txing = 0;
762}
763
764/**
765 * el1_close:
766 * @dev: 3c501 card to shut down
767 *
768 * Close a 3c501 card. The IFF_UP flag has been cleared by the user via
769 * the SIOCSIFFLAGS ioctl. We stop any further transmissions being queued,
770 * and then disable the interrupts. Finally we reset the chip. The effects
771 * of the rest will be cleaned up by #el1_open. Always returns 0 indicating
772 * a success.
773 */
774
775static int el1_close(struct net_device *dev)
776{
777	int ioaddr = dev->base_addr;
778
779	if (el_debug > 2)
780		pr_info("%s: Shutting down Ethernet card at %#x.\n",
781						dev->name, ioaddr);
782
783	netif_stop_queue(dev);
784
785	/*
786	 *	Free and disable the IRQ.
787	 */
788
789	free_irq(dev->irq, dev);
790	outb(AX_RESET, AX_CMD);		/* Reset the chip */
791
792	return 0;
793}
794
795/**
796 * set_multicast_list:
797 * @dev: The device to adjust
798 *
799 * Set or clear the multicast filter for this adaptor to use the best-effort
800 * filtering supported. The 3c501 supports only three modes of filtering.
801 * It always receives broadcasts and packets for itself. You can choose to
802 * optionally receive all packets, or all multicast packets on top of this.
803 */
804
805static void set_multicast_list(struct net_device *dev)
806{
807	int ioaddr = dev->base_addr;
808
809	if (dev->flags & IFF_PROMISC) {
810		outb(RX_PROM, RX_CMD);
811		inb(RX_STATUS);
812	} else if (!netdev_mc_empty(dev) || dev->flags & IFF_ALLMULTI) {
813		/* Multicast or all multicast is the same */
814		outb(RX_MULT, RX_CMD);
815		inb(RX_STATUS);		/* Clear status. */
816	} else {
817		outb(RX_NORM, RX_CMD);
818		inb(RX_STATUS);
819	}
820}
821
822
823static void netdev_get_drvinfo(struct net_device *dev,
824			       struct ethtool_drvinfo *info)
825{
826	strcpy(info->driver, DRV_NAME);
827	strcpy(info->version, DRV_VERSION);
828	sprintf(info->bus_info, "ISA 0x%lx", dev->base_addr);
829}
830
831static u32 netdev_get_msglevel(struct net_device *dev)
832{
833	return debug;
834}
835
836static void netdev_set_msglevel(struct net_device *dev, u32 level)
837{
838	debug = level;
839}
840
841static const struct ethtool_ops netdev_ethtool_ops = {
842	.get_drvinfo		= netdev_get_drvinfo,
843	.get_msglevel		= netdev_get_msglevel,
844	.set_msglevel		= netdev_set_msglevel,
845};
846
847#ifdef MODULE
848
849static struct net_device *dev_3c501;
850
851module_param(io, int, 0);
852module_param(irq, int, 0);
853MODULE_PARM_DESC(io, "EtherLink I/O base address");
854MODULE_PARM_DESC(irq, "EtherLink IRQ number");
855
856/**
857 * init_module:
858 *
859 * When the driver is loaded as a module this function is called. We fake up
860 * a device structure with the base I/O and interrupt set as if it were being
861 * called from Space.c. This minimises the extra code that would otherwise
862 * be required.
863 *
864 * Returns 0 for success or -EIO if a card is not found. Returning an error
865 * here also causes the module to be unloaded
866 */
867
868int __init init_module(void)
869{
870	dev_3c501 = el1_probe(-1);
871	if (IS_ERR(dev_3c501))
872		return PTR_ERR(dev_3c501);
873	return 0;
874}
875
876/**
877 * cleanup_module:
878 *
879 * The module is being unloaded. We unhook our network device from the system
880 * and then free up the resources we took when the card was found.
881 */
882
883void __exit cleanup_module(void)
884{
885	struct net_device *dev = dev_3c501;
886	unregister_netdev(dev);
887	release_region(dev->base_addr, EL1_IO_EXTENT);
888	free_netdev(dev);
889}
890
891#endif /* MODULE */
892
893MODULE_AUTHOR("Donald Becker, Alan Cox");
894MODULE_DESCRIPTION("Support for the ancient 3Com 3c501 ethernet card");
895MODULE_LICENSE("GPL");
896
897