xref: /linux/drivers/net/ethernet/amd/lance.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /* lance.c: An AMD LANCE/PCnet ethernet driver for Linux. */
2 /*
3 	Written/copyright 1993-1998 by Donald Becker.
4 
5 	Copyright 1993 United States Government as represented by the
6 	Director, National Security Agency.
7 	This software may be used and distributed according to the terms
8 	of the GNU General Public License, incorporated herein by reference.
9 
10 	This driver is for the Allied Telesis AT1500 and HP J2405A, and should work
11 	with most other LANCE-based bus-master (NE2100/NE2500) ethercards.
12 
13 	The author may be reached as becker@scyld.com, or C/O
14 	Scyld Computing Corporation
15 	410 Severn Ave., Suite 210
16 	Annapolis MD 21403
17 
18 	Andrey V. Savochkin:
19 	- alignment problem with 1.3.* kernel and some minor changes.
20 	Thomas Bogendoerfer (tsbogend@bigbug.franken.de):
21 	- added support for Linux/Alpha, but removed most of it, because
22         it worked only for the PCI chip.
23       - added hook for the 32bit lance driver
24       - added PCnetPCI II (79C970A) to chip table
25 	Paul Gortmaker (gpg109@rsphy1.anu.edu.au):
26 	- hopefully fix above so Linux/Alpha can use ISA cards too.
27     8/20/96 Fixed 7990 autoIRQ failure and reversed unneeded alignment -djb
28     v1.12 10/27/97 Module support -djb
29     v1.14  2/3/98 Module support modified, made PCI support optional -djb
30     v1.15 5/27/99 Fixed bug in the cleanup_module(). dev->priv was freed
31                   before unregister_netdev() which caused NULL pointer
32                   reference later in the chain (in rtnetlink_fill_ifinfo())
33                   -- Mika Kuoppala <miku@iki.fi>
34 
35     Forward ported v1.14 to 2.1.129, merged the PCI and misc changes from
36     the 2.1 version of the old driver - Alan Cox
37 
38     Get rid of check_region, check kmalloc return in lance_probe1
39     Arnaldo Carvalho de Melo <acme@conectiva.com.br> - 11/01/2001
40 
41 	Reworked detection, added support for Racal InterLan EtherBlaster cards
42 	Vesselin Kostadinov <vesok at yahoo dot com > - 22/4/2004
43 */
44 
45 static const char version[] = "lance.c:v1.16 2006/11/09 dplatt@3do.com, becker@cesdis.gsfc.nasa.gov\n";
46 
47 #include <linux/module.h>
48 #include <linux/kernel.h>
49 #include <linux/string.h>
50 #include <linux/delay.h>
51 #include <linux/errno.h>
52 #include <linux/ioport.h>
53 #include <linux/slab.h>
54 #include <linux/interrupt.h>
55 #include <linux/pci.h>
56 #include <linux/init.h>
57 #include <linux/netdevice.h>
58 #include <linux/etherdevice.h>
59 #include <linux/skbuff.h>
60 #include <linux/mm.h>
61 #include <linux/bitops.h>
62 
63 #include <asm/io.h>
64 #include <asm/dma.h>
65 
66 static unsigned int lance_portlist[] __initdata = { 0x300, 0x320, 0x340, 0x360, 0};
67 static int lance_probe1(struct net_device *dev, int ioaddr, int irq, int options);
68 static int __init do_lance_probe(struct net_device *dev);
69 
70 
71 static struct card {
72 	char id_offset14;
73 	char id_offset15;
74 } cards[] = {
75 	{	//"normal"
76 		.id_offset14 = 0x57,
77 		.id_offset15 = 0x57,
78 	},
79 	{	//NI6510EB
80 		.id_offset14 = 0x52,
81 		.id_offset15 = 0x44,
82 	},
83 	{	//Racal InterLan EtherBlaster
84 		.id_offset14 = 0x52,
85 		.id_offset15 = 0x49,
86 	},
87 };
88 #define NUM_CARDS 3
89 
90 #ifdef LANCE_DEBUG
91 static int lance_debug = LANCE_DEBUG;
92 #else
93 static int lance_debug = 1;
94 #endif
95 
96 /*
97 				Theory of Operation
98 
99 I. Board Compatibility
100 
101 This device driver is designed for the AMD 79C960, the "PCnet-ISA
102 single-chip ethernet controller for ISA".  This chip is used in a wide
103 variety of boards from vendors such as Allied Telesis, HP, Kingston,
104 and Boca.  This driver is also intended to work with older AMD 7990
105 designs, such as the NE1500 and NE2100, and newer 79C961.  For convenience,
106 I use the name LANCE to refer to all of the AMD chips, even though it properly
107 refers only to the original 7990.
108 
109 II. Board-specific settings
110 
111 The driver is designed to work the boards that use the faster
112 bus-master mode, rather than in shared memory mode.	 (Only older designs
113 have on-board buffer memory needed to support the slower shared memory mode.)
114 
115 Most ISA boards have jumpered settings for the I/O base, IRQ line, and DMA
116 channel.  This driver probes the likely base addresses:
117 {0x300, 0x320, 0x340, 0x360}.
118 After the board is found it generates a DMA-timeout interrupt and uses
119 autoIRQ to find the IRQ line.  The DMA channel can be set with the low bits
120 of the otherwise-unused dev->mem_start value (aka PARAM1).  If unset it is
121 probed for by enabling each free DMA channel in turn and checking if
122 initialization succeeds.
123 
124 The HP-J2405A board is an exception: with this board it is easy to read the
125 EEPROM-set values for the base, IRQ, and DMA.  (Of course you must already
126 _know_ the base address -- that field is for writing the EEPROM.)
127 
128 III. Driver operation
129 
130 IIIa. Ring buffers
131 The LANCE uses ring buffers of Tx and Rx descriptors.  Each entry describes
132 the base and length of the data buffer, along with status bits.	 The length
133 of these buffers is set by LANCE_LOG_{RX,TX}_BUFFERS, which is log_2() of
134 the buffer length (rather than being directly the buffer length) for
135 implementation ease.  The current values are 2 (Tx) and 4 (Rx), which leads to
136 ring sizes of 4 (Tx) and 16 (Rx).  Increasing the number of ring entries
137 needlessly uses extra space and reduces the chance that an upper layer will
138 be able to reorder queued Tx packets based on priority.	 Decreasing the number
139 of entries makes it more difficult to achieve back-to-back packet transmission
140 and increases the chance that Rx ring will overflow.  (Consider the worst case
141 of receiving back-to-back minimum-sized packets.)
142 
143 The LANCE has the capability to "chain" both Rx and Tx buffers, but this driver
144 statically allocates full-sized (slightly oversized -- PKT_BUF_SZ) buffers to
145 avoid the administrative overhead. For the Rx side this avoids dynamically
146 allocating full-sized buffers "just in case", at the expense of a
147 memory-to-memory data copy for each packet received.  For most systems this
148 is a good tradeoff: the Rx buffer will always be in low memory, the copy
149 is inexpensive, and it primes the cache for later packet processing.  For Tx
150 the buffers are only used when needed as low-memory bounce buffers.
151 
152 IIIB. 16M memory limitations.
153 For the ISA bus master mode all structures used directly by the LANCE,
154 the initialization block, Rx and Tx rings, and data buffers, must be
155 accessible from the ISA bus, i.e. in the lower 16M of real memory.
156 This is a problem for current Linux kernels on >16M machines. The network
157 devices are initialized after memory initialization, and the kernel doles out
158 memory from the top of memory downward.	 The current solution is to have a
159 special network initialization routine that's called before memory
160 initialization; this will eventually be generalized for all network devices.
161 As mentioned before, low-memory "bounce-buffers" are used when needed.
162 
163 IIIC. Synchronization
164 The driver runs as two independent, single-threaded flows of control.  One
165 is the send-packet routine, which enforces single-threaded use by the
166 dev->tbusy flag.  The other thread is the interrupt handler, which is single
167 threaded by the hardware and other software.
168 
169 The send packet thread has partial control over the Tx ring and 'dev->tbusy'
170 flag.  It sets the tbusy flag whenever it's queuing a Tx packet. If the next
171 queue slot is empty, it clears the tbusy flag when finished otherwise it sets
172 the 'lp->tx_full' flag.
173 
174 The interrupt handler has exclusive control over the Rx ring and records stats
175 from the Tx ring. (The Tx-done interrupt can't be selectively turned off, so
176 we can't avoid the interrupt overhead by having the Tx routine reap the Tx
177 stats.)	 After reaping the stats, it marks the queue entry as empty by setting
178 the 'base' to zero. Iff the 'lp->tx_full' flag is set, it clears both the
179 tx_full and tbusy flags.
180 
181 */
182 
183 /* Set the number of Tx and Rx buffers, using Log_2(# buffers).
184    Reasonable default values are 16 Tx buffers, and 16 Rx buffers.
185    That translates to 4 and 4 (16 == 2^^4).
186    This is a compile-time option for efficiency.
187    */
188 #ifndef LANCE_LOG_TX_BUFFERS
189 #define LANCE_LOG_TX_BUFFERS 4
190 #define LANCE_LOG_RX_BUFFERS 4
191 #endif
192 
193 #define TX_RING_SIZE			(1 << (LANCE_LOG_TX_BUFFERS))
194 #define TX_RING_MOD_MASK		(TX_RING_SIZE - 1)
195 #define TX_RING_LEN_BITS		((LANCE_LOG_TX_BUFFERS) << 29)
196 
197 #define RX_RING_SIZE			(1 << (LANCE_LOG_RX_BUFFERS))
198 #define RX_RING_MOD_MASK		(RX_RING_SIZE - 1)
199 #define RX_RING_LEN_BITS		((LANCE_LOG_RX_BUFFERS) << 29)
200 
201 #define PKT_BUF_SZ		1544
202 
203 /* Offsets from base I/O address. */
204 #define LANCE_DATA 0x10
205 #define LANCE_ADDR 0x12
206 #define LANCE_RESET 0x14
207 #define LANCE_BUS_IF 0x16
208 #define LANCE_TOTAL_SIZE 0x18
209 
210 #define TX_TIMEOUT	(HZ/5)
211 
212 /* The LANCE Rx and Tx ring descriptors. */
213 struct lance_rx_head {
214 	s32 base;
215 	s16 buf_length;			/* This length is 2s complement (negative)! */
216 	s16 msg_length;			/* This length is "normal". */
217 };
218 
219 struct lance_tx_head {
220 	s32 base;
221 	s16 length;				/* Length is 2s complement (negative)! */
222 	s16 misc;
223 };
224 
225 /* The LANCE initialization block, described in databook. */
226 struct lance_init_block {
227 	u16 mode;		/* Pre-set mode (reg. 15) */
228 	u8  phys_addr[6]; /* Physical ethernet address */
229 	u32 filter[2];			/* Multicast filter (unused). */
230 	/* Receive and transmit ring base, along with extra bits. */
231 	u32  rx_ring;			/* Tx and Rx ring base pointers */
232 	u32  tx_ring;
233 };
234 
235 struct lance_private {
236 	/* The Tx and Rx ring entries must be aligned on 8-byte boundaries. */
237 	struct lance_rx_head rx_ring[RX_RING_SIZE];
238 	struct lance_tx_head tx_ring[TX_RING_SIZE];
239 	struct lance_init_block	init_block;
240 	const char *name;
241 	/* The saved address of a sent-in-place packet/buffer, for skfree(). */
242 	struct sk_buff* tx_skbuff[TX_RING_SIZE];
243 	/* The addresses of receive-in-place skbuffs. */
244 	struct sk_buff* rx_skbuff[RX_RING_SIZE];
245 	unsigned long rx_buffs;		/* Address of Rx and Tx buffers. */
246 	/* Tx low-memory "bounce buffer" address. */
247 	char (*tx_bounce_buffs)[PKT_BUF_SZ];
248 	int cur_rx, cur_tx;			/* The next free ring entry */
249 	int dirty_rx, dirty_tx;		/* The ring entries to be free()ed. */
250 	int dma;
251 	unsigned char chip_version;	/* See lance_chip_type. */
252 	spinlock_t devlock;
253 };
254 
255 #define LANCE_MUST_PAD          0x00000001
256 #define LANCE_ENABLE_AUTOSELECT 0x00000002
257 #define LANCE_MUST_REINIT_RING  0x00000004
258 #define LANCE_MUST_UNRESET      0x00000008
259 #define LANCE_HAS_MISSED_FRAME  0x00000010
260 
261 /* A mapping from the chip ID number to the part number and features.
262    These are from the datasheets -- in real life the '970 version
263    reportedly has the same ID as the '965. */
264 static struct lance_chip_type {
265 	int id_number;
266 	const char *name;
267 	int flags;
268 } chip_table[] = {
269 	{0x0000, "LANCE 7990",				/* Ancient lance chip.  */
270 		LANCE_MUST_PAD + LANCE_MUST_UNRESET},
271 	{0x0003, "PCnet/ISA 79C960",		/* 79C960 PCnet/ISA.  */
272 		LANCE_ENABLE_AUTOSELECT + LANCE_MUST_REINIT_RING +
273 			LANCE_HAS_MISSED_FRAME},
274 	{0x2260, "PCnet/ISA+ 79C961",		/* 79C961 PCnet/ISA+, Plug-n-Play.  */
275 		LANCE_ENABLE_AUTOSELECT + LANCE_MUST_REINIT_RING +
276 			LANCE_HAS_MISSED_FRAME},
277 	{0x2420, "PCnet/PCI 79C970",		/* 79C970 or 79C974 PCnet-SCSI, PCI. */
278 		LANCE_ENABLE_AUTOSELECT + LANCE_MUST_REINIT_RING +
279 			LANCE_HAS_MISSED_FRAME},
280 	/* Bug: the PCnet/PCI actually uses the PCnet/VLB ID number, so just call
281 		it the PCnet32. */
282 	{0x2430, "PCnet32",					/* 79C965 PCnet for VL bus. */
283 		LANCE_ENABLE_AUTOSELECT + LANCE_MUST_REINIT_RING +
284 			LANCE_HAS_MISSED_FRAME},
285         {0x2621, "PCnet/PCI-II 79C970A",        /* 79C970A PCInetPCI II. */
286                 LANCE_ENABLE_AUTOSELECT + LANCE_MUST_REINIT_RING +
287                         LANCE_HAS_MISSED_FRAME},
288 	{0x0, 	 "PCnet (unknown)",
289 		LANCE_ENABLE_AUTOSELECT + LANCE_MUST_REINIT_RING +
290 			LANCE_HAS_MISSED_FRAME},
291 };
292 
293 enum {OLD_LANCE = 0, PCNET_ISA=1, PCNET_ISAP=2, PCNET_PCI=3, PCNET_VLB=4, PCNET_PCI_II=5, LANCE_UNKNOWN=6};
294 
295 
296 /* Non-zero if lance_probe1() needs to allocate low-memory bounce buffers.
297    Assume yes until we know the memory size. */
298 static unsigned char lance_need_isa_bounce_buffers = 1;
299 
300 static int lance_open(struct net_device *dev);
301 static void lance_init_ring(struct net_device *dev, gfp_t mode);
302 static netdev_tx_t lance_start_xmit(struct sk_buff *skb,
303 				    struct net_device *dev);
304 static int lance_rx(struct net_device *dev);
305 static irqreturn_t lance_interrupt(int irq, void *dev_id);
306 static int lance_close(struct net_device *dev);
307 static struct net_device_stats *lance_get_stats(struct net_device *dev);
308 static void set_multicast_list(struct net_device *dev);
309 static void lance_tx_timeout (struct net_device *dev);
310 
311 
312 
313 #ifdef MODULE
314 #define MAX_CARDS		8	/* Max number of interfaces (cards) per module */
315 
316 static struct net_device *dev_lance[MAX_CARDS];
317 static int io[MAX_CARDS];
318 static int dma[MAX_CARDS];
319 static int irq[MAX_CARDS];
320 
321 module_param_array(io, int, NULL, 0);
322 module_param_array(dma, int, NULL, 0);
323 module_param_array(irq, int, NULL, 0);
324 module_param(lance_debug, int, 0);
325 MODULE_PARM_DESC(io, "LANCE/PCnet I/O base address(es),required");
326 MODULE_PARM_DESC(dma, "LANCE/PCnet ISA DMA channel (ignored for some devices)");
327 MODULE_PARM_DESC(irq, "LANCE/PCnet IRQ number (ignored for some devices)");
328 MODULE_PARM_DESC(lance_debug, "LANCE/PCnet debug level (0-7)");
329 
330 int __init init_module(void)
331 {
332 	struct net_device *dev;
333 	int this_dev, found = 0;
334 
335 	for (this_dev = 0; this_dev < MAX_CARDS; this_dev++) {
336 		if (io[this_dev] == 0)  {
337 			if (this_dev != 0) /* only complain once */
338 				break;
339 			printk(KERN_NOTICE "lance.c: Module autoprobing not allowed. Append \"io=0xNNN\" value(s).\n");
340 			return -EPERM;
341 		}
342 		dev = alloc_etherdev(0);
343 		if (!dev)
344 			break;
345 		dev->irq = irq[this_dev];
346 		dev->base_addr = io[this_dev];
347 		dev->dma = dma[this_dev];
348 		if (do_lance_probe(dev) == 0) {
349 			dev_lance[found++] = dev;
350 			continue;
351 		}
352 		free_netdev(dev);
353 		break;
354 	}
355 	if (found != 0)
356 		return 0;
357 	return -ENXIO;
358 }
359 
360 static void cleanup_card(struct net_device *dev)
361 {
362 	struct lance_private *lp = dev->ml_priv;
363 	if (dev->dma != 4)
364 		free_dma(dev->dma);
365 	release_region(dev->base_addr, LANCE_TOTAL_SIZE);
366 	kfree(lp->tx_bounce_buffs);
367 	kfree((void*)lp->rx_buffs);
368 	kfree(lp);
369 }
370 
371 void __exit cleanup_module(void)
372 {
373 	int this_dev;
374 
375 	for (this_dev = 0; this_dev < MAX_CARDS; this_dev++) {
376 		struct net_device *dev = dev_lance[this_dev];
377 		if (dev) {
378 			unregister_netdev(dev);
379 			cleanup_card(dev);
380 			free_netdev(dev);
381 		}
382 	}
383 }
384 #endif /* MODULE */
385 MODULE_LICENSE("GPL");
386 
387 
388 /* Starting in v2.1.*, the LANCE/PCnet probe is now similar to the other
389    board probes now that kmalloc() can allocate ISA DMA-able regions.
390    This also allows the LANCE driver to be used as a module.
391    */
392 static int __init do_lance_probe(struct net_device *dev)
393 {
394 	unsigned int *port;
395 	int result;
396 
397 	if (high_memory <= phys_to_virt(16*1024*1024))
398 		lance_need_isa_bounce_buffers = 0;
399 
400 	for (port = lance_portlist; *port; port++) {
401 		int ioaddr = *port;
402 		struct resource *r = request_region(ioaddr, LANCE_TOTAL_SIZE,
403 							"lance-probe");
404 
405 		if (r) {
406 			/* Detect the card with minimal I/O reads */
407 			char offset14 = inb(ioaddr + 14);
408 			int card;
409 			for (card = 0; card < NUM_CARDS; ++card)
410 				if (cards[card].id_offset14 == offset14)
411 					break;
412 			if (card < NUM_CARDS) {/*yes, the first byte matches*/
413 				char offset15 = inb(ioaddr + 15);
414 				for (card = 0; card < NUM_CARDS; ++card)
415 					if ((cards[card].id_offset14 == offset14) &&
416 						(cards[card].id_offset15 == offset15))
417 						break;
418 			}
419 			if (card < NUM_CARDS) { /*Signature OK*/
420 				result = lance_probe1(dev, ioaddr, 0, 0);
421 				if (!result) {
422 					struct lance_private *lp = dev->ml_priv;
423 					int ver = lp->chip_version;
424 
425 					r->name = chip_table[ver].name;
426 					return 0;
427 				}
428 			}
429 			release_region(ioaddr, LANCE_TOTAL_SIZE);
430 		}
431 	}
432 	return -ENODEV;
433 }
434 
435 #ifndef MODULE
436 struct net_device * __init lance_probe(int unit)
437 {
438 	struct net_device *dev = alloc_etherdev(0);
439 	int err;
440 
441 	if (!dev)
442 		return ERR_PTR(-ENODEV);
443 
444 	sprintf(dev->name, "eth%d", unit);
445 	netdev_boot_setup_check(dev);
446 
447 	err = do_lance_probe(dev);
448 	if (err)
449 		goto out;
450 	return dev;
451 out:
452 	free_netdev(dev);
453 	return ERR_PTR(err);
454 }
455 #endif
456 
457 static const struct net_device_ops lance_netdev_ops = {
458 	.ndo_open 		= lance_open,
459 	.ndo_start_xmit		= lance_start_xmit,
460 	.ndo_stop		= lance_close,
461 	.ndo_get_stats		= lance_get_stats,
462 	.ndo_set_rx_mode	= set_multicast_list,
463 	.ndo_tx_timeout		= lance_tx_timeout,
464 	.ndo_change_mtu		= eth_change_mtu,
465 	.ndo_set_mac_address 	= eth_mac_addr,
466 	.ndo_validate_addr	= eth_validate_addr,
467 };
468 
469 static int __init lance_probe1(struct net_device *dev, int ioaddr, int irq, int options)
470 {
471 	struct lance_private *lp;
472 	unsigned long dma_channels;	/* Mark spuriously-busy DMA channels */
473 	int i, reset_val, lance_version;
474 	const char *chipname;
475 	/* Flags for specific chips or boards. */
476 	unsigned char hpJ2405A = 0;	/* HP ISA adaptor */
477 	int hp_builtin = 0;		/* HP on-board ethernet. */
478 	static int did_version;		/* Already printed version info. */
479 	unsigned long flags;
480 	int err = -ENOMEM;
481 	void __iomem *bios;
482 
483 	/* First we look for special cases.
484 	   Check for HP's on-board ethernet by looking for 'HP' in the BIOS.
485 	   There are two HP versions, check the BIOS for the configuration port.
486 	   This method provided by L. Julliard, Laurent_Julliard@grenoble.hp.com.
487 	   */
488 	bios = ioremap(0xf00f0, 0x14);
489 	if (!bios)
490 		return -ENOMEM;
491 	if (readw(bios + 0x12) == 0x5048)  {
492 		static const short ioaddr_table[] = { 0x300, 0x320, 0x340, 0x360};
493 		int hp_port = (readl(bios + 1) & 1)  ? 0x499 : 0x99;
494 		/* We can have boards other than the built-in!  Verify this is on-board. */
495 		if ((inb(hp_port) & 0xc0) == 0x80 &&
496 		    ioaddr_table[inb(hp_port) & 3] == ioaddr)
497 			hp_builtin = hp_port;
498 	}
499 	iounmap(bios);
500 	/* We also recognize the HP Vectra on-board here, but check below. */
501 	hpJ2405A = (inb(ioaddr) == 0x08 && inb(ioaddr+1) == 0x00 &&
502 		    inb(ioaddr+2) == 0x09);
503 
504 	/* Reset the LANCE.	 */
505 	reset_val = inw(ioaddr+LANCE_RESET); /* Reset the LANCE */
506 
507 	/* The Un-Reset needed is only needed for the real NE2100, and will
508 	   confuse the HP board. */
509 	if (!hpJ2405A)
510 		outw(reset_val, ioaddr+LANCE_RESET);
511 
512 	outw(0x0000, ioaddr+LANCE_ADDR); /* Switch to window 0 */
513 	if (inw(ioaddr+LANCE_DATA) != 0x0004)
514 		return -ENODEV;
515 
516 	/* Get the version of the chip. */
517 	outw(88, ioaddr+LANCE_ADDR);
518 	if (inw(ioaddr+LANCE_ADDR) != 88) {
519 		lance_version = 0;
520 	} else {			/* Good, it's a newer chip. */
521 		int chip_version = inw(ioaddr+LANCE_DATA);
522 		outw(89, ioaddr+LANCE_ADDR);
523 		chip_version |= inw(ioaddr+LANCE_DATA) << 16;
524 		if (lance_debug > 2)
525 			printk("  LANCE chip version is %#x.\n", chip_version);
526 		if ((chip_version & 0xfff) != 0x003)
527 			return -ENODEV;
528 		chip_version = (chip_version >> 12) & 0xffff;
529 		for (lance_version = 1; chip_table[lance_version].id_number; lance_version++) {
530 			if (chip_table[lance_version].id_number == chip_version)
531 				break;
532 		}
533 	}
534 
535 	/* We can't allocate private data from alloc_etherdev() because it must
536 	   a ISA DMA-able region. */
537 	chipname = chip_table[lance_version].name;
538 	printk("%s: %s at %#3x, ", dev->name, chipname, ioaddr);
539 
540 	/* There is a 16 byte station address PROM at the base address.
541 	   The first six bytes are the station address. */
542 	for (i = 0; i < 6; i++)
543 		dev->dev_addr[i] = inb(ioaddr + i);
544 	printk("%pM", dev->dev_addr);
545 
546 	dev->base_addr = ioaddr;
547 	/* Make certain the data structures used by the LANCE are aligned and DMAble. */
548 
549 	lp = kzalloc(sizeof(*lp), GFP_DMA | GFP_KERNEL);
550 	if(lp==NULL)
551 		return -ENODEV;
552 	if (lance_debug > 6) printk(" (#0x%05lx)", (unsigned long)lp);
553 	dev->ml_priv = lp;
554 	lp->name = chipname;
555 	lp->rx_buffs = (unsigned long)kmalloc(PKT_BUF_SZ*RX_RING_SIZE,
556 						  GFP_DMA | GFP_KERNEL);
557 	if (!lp->rx_buffs)
558 		goto out_lp;
559 	if (lance_need_isa_bounce_buffers) {
560 		lp->tx_bounce_buffs = kmalloc(PKT_BUF_SZ*TX_RING_SIZE,
561 						  GFP_DMA | GFP_KERNEL);
562 		if (!lp->tx_bounce_buffs)
563 			goto out_rx;
564 	} else
565 		lp->tx_bounce_buffs = NULL;
566 
567 	lp->chip_version = lance_version;
568 	spin_lock_init(&lp->devlock);
569 
570 	lp->init_block.mode = 0x0003;		/* Disable Rx and Tx. */
571 	for (i = 0; i < 6; i++)
572 		lp->init_block.phys_addr[i] = dev->dev_addr[i];
573 	lp->init_block.filter[0] = 0x00000000;
574 	lp->init_block.filter[1] = 0x00000000;
575 	lp->init_block.rx_ring = ((u32)isa_virt_to_bus(lp->rx_ring) & 0xffffff) | RX_RING_LEN_BITS;
576 	lp->init_block.tx_ring = ((u32)isa_virt_to_bus(lp->tx_ring) & 0xffffff) | TX_RING_LEN_BITS;
577 
578 	outw(0x0001, ioaddr+LANCE_ADDR);
579 	inw(ioaddr+LANCE_ADDR);
580 	outw((short) (u32) isa_virt_to_bus(&lp->init_block), ioaddr+LANCE_DATA);
581 	outw(0x0002, ioaddr+LANCE_ADDR);
582 	inw(ioaddr+LANCE_ADDR);
583 	outw(((u32)isa_virt_to_bus(&lp->init_block)) >> 16, ioaddr+LANCE_DATA);
584 	outw(0x0000, ioaddr+LANCE_ADDR);
585 	inw(ioaddr+LANCE_ADDR);
586 
587 	if (irq) {					/* Set iff PCI card. */
588 		dev->dma = 4;			/* Native bus-master, no DMA channel needed. */
589 		dev->irq = irq;
590 	} else if (hp_builtin) {
591 		static const char dma_tbl[4] = {3, 5, 6, 0};
592 		static const char irq_tbl[4] = {3, 4, 5, 9};
593 		unsigned char port_val = inb(hp_builtin);
594 		dev->dma = dma_tbl[(port_val >> 4) & 3];
595 		dev->irq = irq_tbl[(port_val >> 2) & 3];
596 		printk(" HP Vectra IRQ %d DMA %d.\n", dev->irq, dev->dma);
597 	} else if (hpJ2405A) {
598 		static const char dma_tbl[4] = {3, 5, 6, 7};
599 		static const char irq_tbl[8] = {3, 4, 5, 9, 10, 11, 12, 15};
600 		short reset_val = inw(ioaddr+LANCE_RESET);
601 		dev->dma = dma_tbl[(reset_val >> 2) & 3];
602 		dev->irq = irq_tbl[(reset_val >> 4) & 7];
603 		printk(" HP J2405A IRQ %d DMA %d.\n", dev->irq, dev->dma);
604 	} else if (lance_version == PCNET_ISAP) {		/* The plug-n-play version. */
605 		short bus_info;
606 		outw(8, ioaddr+LANCE_ADDR);
607 		bus_info = inw(ioaddr+LANCE_BUS_IF);
608 		dev->dma = bus_info & 0x07;
609 		dev->irq = (bus_info >> 4) & 0x0F;
610 	} else {
611 		/* The DMA channel may be passed in PARAM1. */
612 		if (dev->mem_start & 0x07)
613 			dev->dma = dev->mem_start & 0x07;
614 	}
615 
616 	if (dev->dma == 0) {
617 		/* Read the DMA channel status register, so that we can avoid
618 		   stuck DMA channels in the DMA detection below. */
619 		dma_channels = ((inb(DMA1_STAT_REG) >> 4) & 0x0f) |
620 			(inb(DMA2_STAT_REG) & 0xf0);
621 	}
622 	err = -ENODEV;
623 	if (dev->irq >= 2)
624 		printk(" assigned IRQ %d", dev->irq);
625 	else if (lance_version != 0)  {	/* 7990 boards need DMA detection first. */
626 		unsigned long irq_mask;
627 
628 		/* To auto-IRQ we enable the initialization-done and DMA error
629 		   interrupts. For ISA boards we get a DMA error, but VLB and PCI
630 		   boards will work. */
631 		irq_mask = probe_irq_on();
632 
633 		/* Trigger an initialization just for the interrupt. */
634 		outw(0x0041, ioaddr+LANCE_DATA);
635 
636 		mdelay(20);
637 		dev->irq = probe_irq_off(irq_mask);
638 		if (dev->irq)
639 			printk(", probed IRQ %d", dev->irq);
640 		else {
641 			printk(", failed to detect IRQ line.\n");
642 			goto out_tx;
643 		}
644 
645 		/* Check for the initialization done bit, 0x0100, which means
646 		   that we don't need a DMA channel. */
647 		if (inw(ioaddr+LANCE_DATA) & 0x0100)
648 			dev->dma = 4;
649 	}
650 
651 	if (dev->dma == 4) {
652 		printk(", no DMA needed.\n");
653 	} else if (dev->dma) {
654 		if (request_dma(dev->dma, chipname)) {
655 			printk("DMA %d allocation failed.\n", dev->dma);
656 			goto out_tx;
657 		} else
658 			printk(", assigned DMA %d.\n", dev->dma);
659 	} else {			/* OK, we have to auto-DMA. */
660 		for (i = 0; i < 4; i++) {
661 			static const char dmas[] = { 5, 6, 7, 3 };
662 			int dma = dmas[i];
663 			int boguscnt;
664 
665 			/* Don't enable a permanently busy DMA channel, or the machine
666 			   will hang. */
667 			if (test_bit(dma, &dma_channels))
668 				continue;
669 			outw(0x7f04, ioaddr+LANCE_DATA); /* Clear the memory error bits. */
670 			if (request_dma(dma, chipname))
671 				continue;
672 
673 			flags=claim_dma_lock();
674 			set_dma_mode(dma, DMA_MODE_CASCADE);
675 			enable_dma(dma);
676 			release_dma_lock(flags);
677 
678 			/* Trigger an initialization. */
679 			outw(0x0001, ioaddr+LANCE_DATA);
680 			for (boguscnt = 100; boguscnt > 0; --boguscnt)
681 				if (inw(ioaddr+LANCE_DATA) & 0x0900)
682 					break;
683 			if (inw(ioaddr+LANCE_DATA) & 0x0100) {
684 				dev->dma = dma;
685 				printk(", DMA %d.\n", dev->dma);
686 				break;
687 			} else {
688 				flags=claim_dma_lock();
689 				disable_dma(dma);
690 				release_dma_lock(flags);
691 				free_dma(dma);
692 			}
693 		}
694 		if (i == 4) {			/* Failure: bail. */
695 			printk("DMA detection failed.\n");
696 			goto out_tx;
697 		}
698 	}
699 
700 	if (lance_version == 0 && dev->irq == 0) {
701 		/* We may auto-IRQ now that we have a DMA channel. */
702 		/* Trigger an initialization just for the interrupt. */
703 		unsigned long irq_mask;
704 
705 		irq_mask = probe_irq_on();
706 		outw(0x0041, ioaddr+LANCE_DATA);
707 
708 		mdelay(40);
709 		dev->irq = probe_irq_off(irq_mask);
710 		if (dev->irq == 0) {
711 			printk("  Failed to detect the 7990 IRQ line.\n");
712 			goto out_dma;
713 		}
714 		printk("  Auto-IRQ detected IRQ%d.\n", dev->irq);
715 	}
716 
717 	if (chip_table[lp->chip_version].flags & LANCE_ENABLE_AUTOSELECT) {
718 		/* Turn on auto-select of media (10baseT or BNC) so that the user
719 		   can watch the LEDs even if the board isn't opened. */
720 		outw(0x0002, ioaddr+LANCE_ADDR);
721 		/* Don't touch 10base2 power bit. */
722 		outw(inw(ioaddr+LANCE_BUS_IF) | 0x0002, ioaddr+LANCE_BUS_IF);
723 	}
724 
725 	if (lance_debug > 0  &&  did_version++ == 0)
726 		printk(version);
727 
728 	/* The LANCE-specific entries in the device structure. */
729 	dev->netdev_ops = &lance_netdev_ops;
730 	dev->watchdog_timeo = TX_TIMEOUT;
731 
732 	err = register_netdev(dev);
733 	if (err)
734 		goto out_dma;
735 	return 0;
736 out_dma:
737 	if (dev->dma != 4)
738 		free_dma(dev->dma);
739 out_tx:
740 	kfree(lp->tx_bounce_buffs);
741 out_rx:
742 	kfree((void*)lp->rx_buffs);
743 out_lp:
744 	kfree(lp);
745 	return err;
746 }
747 
748 
749 static int
750 lance_open(struct net_device *dev)
751 {
752 	struct lance_private *lp = dev->ml_priv;
753 	int ioaddr = dev->base_addr;
754 	int i;
755 
756 	if (dev->irq == 0 ||
757 		request_irq(dev->irq, lance_interrupt, 0, dev->name, dev)) {
758 		return -EAGAIN;
759 	}
760 
761 	/* We used to allocate DMA here, but that was silly.
762 	   DMA lines can't be shared!  We now permanently allocate them. */
763 
764 	/* Reset the LANCE */
765 	inw(ioaddr+LANCE_RESET);
766 
767 	/* The DMA controller is used as a no-operation slave, "cascade mode". */
768 	if (dev->dma != 4) {
769 		unsigned long flags=claim_dma_lock();
770 		enable_dma(dev->dma);
771 		set_dma_mode(dev->dma, DMA_MODE_CASCADE);
772 		release_dma_lock(flags);
773 	}
774 
775 	/* Un-Reset the LANCE, needed only for the NE2100. */
776 	if (chip_table[lp->chip_version].flags & LANCE_MUST_UNRESET)
777 		outw(0, ioaddr+LANCE_RESET);
778 
779 	if (chip_table[lp->chip_version].flags & LANCE_ENABLE_AUTOSELECT) {
780 		/* This is 79C960-specific: Turn on auto-select of media (AUI, BNC). */
781 		outw(0x0002, ioaddr+LANCE_ADDR);
782 		/* Only touch autoselect bit. */
783 		outw(inw(ioaddr+LANCE_BUS_IF) | 0x0002, ioaddr+LANCE_BUS_IF);
784  	}
785 
786 	if (lance_debug > 1)
787 		printk("%s: lance_open() irq %d dma %d tx/rx rings %#x/%#x init %#x.\n",
788 			   dev->name, dev->irq, dev->dma,
789 		           (u32) isa_virt_to_bus(lp->tx_ring),
790 		           (u32) isa_virt_to_bus(lp->rx_ring),
791 			   (u32) isa_virt_to_bus(&lp->init_block));
792 
793 	lance_init_ring(dev, GFP_KERNEL);
794 	/* Re-initialize the LANCE, and start it when done. */
795 	outw(0x0001, ioaddr+LANCE_ADDR);
796 	outw((short) (u32) isa_virt_to_bus(&lp->init_block), ioaddr+LANCE_DATA);
797 	outw(0x0002, ioaddr+LANCE_ADDR);
798 	outw(((u32)isa_virt_to_bus(&lp->init_block)) >> 16, ioaddr+LANCE_DATA);
799 
800 	outw(0x0004, ioaddr+LANCE_ADDR);
801 	outw(0x0915, ioaddr+LANCE_DATA);
802 
803 	outw(0x0000, ioaddr+LANCE_ADDR);
804 	outw(0x0001, ioaddr+LANCE_DATA);
805 
806 	netif_start_queue (dev);
807 
808 	i = 0;
809 	while (i++ < 100)
810 		if (inw(ioaddr+LANCE_DATA) & 0x0100)
811 			break;
812 	/*
813 	 * We used to clear the InitDone bit, 0x0100, here but Mark Stockton
814 	 * reports that doing so triggers a bug in the '974.
815 	 */
816  	outw(0x0042, ioaddr+LANCE_DATA);
817 
818 	if (lance_debug > 2)
819 		printk("%s: LANCE open after %d ticks, init block %#x csr0 %4.4x.\n",
820 			   dev->name, i, (u32) isa_virt_to_bus(&lp->init_block), inw(ioaddr+LANCE_DATA));
821 
822 	return 0;					/* Always succeed */
823 }
824 
825 /* The LANCE has been halted for one reason or another (busmaster memory
826    arbitration error, Tx FIFO underflow, driver stopped it to reconfigure,
827    etc.).  Modern LANCE variants always reload their ring-buffer
828    configuration when restarted, so we must reinitialize our ring
829    context before restarting.  As part of this reinitialization,
830    find all packets still on the Tx ring and pretend that they had been
831    sent (in effect, drop the packets on the floor) - the higher-level
832    protocols will time out and retransmit.  It'd be better to shuffle
833    these skbs to a temp list and then actually re-Tx them after
834    restarting the chip, but I'm too lazy to do so right now.  dplatt@3do.com
835 */
836 
837 static void
838 lance_purge_ring(struct net_device *dev)
839 {
840 	struct lance_private *lp = dev->ml_priv;
841 	int i;
842 
843 	/* Free all the skbuffs in the Rx and Tx queues. */
844 	for (i = 0; i < RX_RING_SIZE; i++) {
845 		struct sk_buff *skb = lp->rx_skbuff[i];
846 		lp->rx_skbuff[i] = NULL;
847 		lp->rx_ring[i].base = 0;		/* Not owned by LANCE chip. */
848 		if (skb)
849 			dev_kfree_skb_any(skb);
850 	}
851 	for (i = 0; i < TX_RING_SIZE; i++) {
852 		if (lp->tx_skbuff[i]) {
853 			dev_kfree_skb_any(lp->tx_skbuff[i]);
854 			lp->tx_skbuff[i] = NULL;
855 		}
856 	}
857 }
858 
859 
860 /* Initialize the LANCE Rx and Tx rings. */
861 static void
862 lance_init_ring(struct net_device *dev, gfp_t gfp)
863 {
864 	struct lance_private *lp = dev->ml_priv;
865 	int i;
866 
867 	lp->cur_rx = lp->cur_tx = 0;
868 	lp->dirty_rx = lp->dirty_tx = 0;
869 
870 	for (i = 0; i < RX_RING_SIZE; i++) {
871 		struct sk_buff *skb;
872 		void *rx_buff;
873 
874 		skb = alloc_skb(PKT_BUF_SZ, GFP_DMA | gfp);
875 		lp->rx_skbuff[i] = skb;
876 		if (skb)
877 			rx_buff = skb->data;
878 		else
879 			rx_buff = kmalloc(PKT_BUF_SZ, GFP_DMA | gfp);
880 		if (rx_buff == NULL)
881 			lp->rx_ring[i].base = 0;
882 		else
883 			lp->rx_ring[i].base = (u32)isa_virt_to_bus(rx_buff) | 0x80000000;
884 		lp->rx_ring[i].buf_length = -PKT_BUF_SZ;
885 	}
886 	/* The Tx buffer address is filled in as needed, but we do need to clear
887 	   the upper ownership bit. */
888 	for (i = 0; i < TX_RING_SIZE; i++) {
889 		lp->tx_skbuff[i] = NULL;
890 		lp->tx_ring[i].base = 0;
891 	}
892 
893 	lp->init_block.mode = 0x0000;
894 	for (i = 0; i < 6; i++)
895 		lp->init_block.phys_addr[i] = dev->dev_addr[i];
896 	lp->init_block.filter[0] = 0x00000000;
897 	lp->init_block.filter[1] = 0x00000000;
898 	lp->init_block.rx_ring = ((u32)isa_virt_to_bus(lp->rx_ring) & 0xffffff) | RX_RING_LEN_BITS;
899 	lp->init_block.tx_ring = ((u32)isa_virt_to_bus(lp->tx_ring) & 0xffffff) | TX_RING_LEN_BITS;
900 }
901 
902 static void
903 lance_restart(struct net_device *dev, unsigned int csr0_bits, int must_reinit)
904 {
905 	struct lance_private *lp = dev->ml_priv;
906 
907 	if (must_reinit ||
908 		(chip_table[lp->chip_version].flags & LANCE_MUST_REINIT_RING)) {
909 		lance_purge_ring(dev);
910 		lance_init_ring(dev, GFP_ATOMIC);
911 	}
912 	outw(0x0000,    dev->base_addr + LANCE_ADDR);
913 	outw(csr0_bits, dev->base_addr + LANCE_DATA);
914 }
915 
916 
917 static void lance_tx_timeout (struct net_device *dev)
918 {
919 	struct lance_private *lp = (struct lance_private *) dev->ml_priv;
920 	int ioaddr = dev->base_addr;
921 
922 	outw (0, ioaddr + LANCE_ADDR);
923 	printk ("%s: transmit timed out, status %4.4x, resetting.\n",
924 		dev->name, inw (ioaddr + LANCE_DATA));
925 	outw (0x0004, ioaddr + LANCE_DATA);
926 	dev->stats.tx_errors++;
927 #ifndef final_version
928 	if (lance_debug > 3) {
929 		int i;
930 		printk (" Ring data dump: dirty_tx %d cur_tx %d%s cur_rx %d.",
931 		  lp->dirty_tx, lp->cur_tx, netif_queue_stopped(dev) ? " (full)" : "",
932 			lp->cur_rx);
933 		for (i = 0; i < RX_RING_SIZE; i++)
934 			printk ("%s %08x %04x %04x", i & 0x3 ? "" : "\n ",
935 			 lp->rx_ring[i].base, -lp->rx_ring[i].buf_length,
936 				lp->rx_ring[i].msg_length);
937 		for (i = 0; i < TX_RING_SIZE; i++)
938 			printk ("%s %08x %04x %04x", i & 0x3 ? "" : "\n ",
939 			     lp->tx_ring[i].base, -lp->tx_ring[i].length,
940 				lp->tx_ring[i].misc);
941 		printk ("\n");
942 	}
943 #endif
944 	lance_restart (dev, 0x0043, 1);
945 
946 	dev->trans_start = jiffies; /* prevent tx timeout */
947 	netif_wake_queue (dev);
948 }
949 
950 
951 static netdev_tx_t lance_start_xmit(struct sk_buff *skb,
952 				    struct net_device *dev)
953 {
954 	struct lance_private *lp = dev->ml_priv;
955 	int ioaddr = dev->base_addr;
956 	int entry;
957 	unsigned long flags;
958 
959 	spin_lock_irqsave(&lp->devlock, flags);
960 
961 	if (lance_debug > 3) {
962 		outw(0x0000, ioaddr+LANCE_ADDR);
963 		printk("%s: lance_start_xmit() called, csr0 %4.4x.\n", dev->name,
964 			   inw(ioaddr+LANCE_DATA));
965 		outw(0x0000, ioaddr+LANCE_DATA);
966 	}
967 
968 	/* Fill in a Tx ring entry */
969 
970 	/* Mask to ring buffer boundary. */
971 	entry = lp->cur_tx & TX_RING_MOD_MASK;
972 
973 	/* Caution: the write order is important here, set the base address
974 	   with the "ownership" bits last. */
975 
976 	/* The old LANCE chips doesn't automatically pad buffers to min. size. */
977 	if (chip_table[lp->chip_version].flags & LANCE_MUST_PAD) {
978 		if (skb->len < ETH_ZLEN) {
979 			if (skb_padto(skb, ETH_ZLEN))
980 				goto out;
981 			lp->tx_ring[entry].length = -ETH_ZLEN;
982 		}
983 		else
984 			lp->tx_ring[entry].length = -skb->len;
985 	} else
986 		lp->tx_ring[entry].length = -skb->len;
987 
988 	lp->tx_ring[entry].misc = 0x0000;
989 
990 	dev->stats.tx_bytes += skb->len;
991 
992 	/* If any part of this buffer is >16M we must copy it to a low-memory
993 	   buffer. */
994 	if ((u32)isa_virt_to_bus(skb->data) + skb->len > 0x01000000) {
995 		if (lance_debug > 5)
996 			printk("%s: bouncing a high-memory packet (%#x).\n",
997 				   dev->name, (u32)isa_virt_to_bus(skb->data));
998 		skb_copy_from_linear_data(skb, &lp->tx_bounce_buffs[entry], skb->len);
999 		lp->tx_ring[entry].base =
1000 			((u32)isa_virt_to_bus((lp->tx_bounce_buffs + entry)) & 0xffffff) | 0x83000000;
1001 		dev_kfree_skb(skb);
1002 	} else {
1003 		lp->tx_skbuff[entry] = skb;
1004 		lp->tx_ring[entry].base = ((u32)isa_virt_to_bus(skb->data) & 0xffffff) | 0x83000000;
1005 	}
1006 	lp->cur_tx++;
1007 
1008 	/* Trigger an immediate send poll. */
1009 	outw(0x0000, ioaddr+LANCE_ADDR);
1010 	outw(0x0048, ioaddr+LANCE_DATA);
1011 
1012 	if ((lp->cur_tx - lp->dirty_tx) >= TX_RING_SIZE)
1013 		netif_stop_queue(dev);
1014 
1015 out:
1016 	spin_unlock_irqrestore(&lp->devlock, flags);
1017 	return NETDEV_TX_OK;
1018 }
1019 
1020 /* The LANCE interrupt handler. */
1021 static irqreturn_t lance_interrupt(int irq, void *dev_id)
1022 {
1023 	struct net_device *dev = dev_id;
1024 	struct lance_private *lp;
1025 	int csr0, ioaddr, boguscnt=10;
1026 	int must_restart;
1027 
1028 	ioaddr = dev->base_addr;
1029 	lp = dev->ml_priv;
1030 
1031 	spin_lock (&lp->devlock);
1032 
1033 	outw(0x00, dev->base_addr + LANCE_ADDR);
1034 	while ((csr0 = inw(dev->base_addr + LANCE_DATA)) & 0x8600 &&
1035 	       --boguscnt >= 0) {
1036 		/* Acknowledge all of the current interrupt sources ASAP. */
1037 		outw(csr0 & ~0x004f, dev->base_addr + LANCE_DATA);
1038 
1039 		must_restart = 0;
1040 
1041 		if (lance_debug > 5)
1042 			printk("%s: interrupt  csr0=%#2.2x new csr=%#2.2x.\n",
1043 				   dev->name, csr0, inw(dev->base_addr + LANCE_DATA));
1044 
1045 		if (csr0 & 0x0400)			/* Rx interrupt */
1046 			lance_rx(dev);
1047 
1048 		if (csr0 & 0x0200) {		/* Tx-done interrupt */
1049 			int dirty_tx = lp->dirty_tx;
1050 
1051 			while (dirty_tx < lp->cur_tx) {
1052 				int entry = dirty_tx & TX_RING_MOD_MASK;
1053 				int status = lp->tx_ring[entry].base;
1054 
1055 				if (status < 0)
1056 					break;			/* It still hasn't been Txed */
1057 
1058 				lp->tx_ring[entry].base = 0;
1059 
1060 				if (status & 0x40000000) {
1061 					/* There was an major error, log it. */
1062 					int err_status = lp->tx_ring[entry].misc;
1063 					dev->stats.tx_errors++;
1064 					if (err_status & 0x0400)
1065 						dev->stats.tx_aborted_errors++;
1066 					if (err_status & 0x0800)
1067 						dev->stats.tx_carrier_errors++;
1068 					if (err_status & 0x1000)
1069 						dev->stats.tx_window_errors++;
1070 					if (err_status & 0x4000) {
1071 						/* Ackk!  On FIFO errors the Tx unit is turned off! */
1072 						dev->stats.tx_fifo_errors++;
1073 						/* Remove this verbosity later! */
1074 						printk("%s: Tx FIFO error! Status %4.4x.\n",
1075 							   dev->name, csr0);
1076 						/* Restart the chip. */
1077 						must_restart = 1;
1078 					}
1079 				} else {
1080 					if (status & 0x18000000)
1081 						dev->stats.collisions++;
1082 					dev->stats.tx_packets++;
1083 				}
1084 
1085 				/* We must free the original skb if it's not a data-only copy
1086 				   in the bounce buffer. */
1087 				if (lp->tx_skbuff[entry]) {
1088 					dev_kfree_skb_irq(lp->tx_skbuff[entry]);
1089 					lp->tx_skbuff[entry] = NULL;
1090 				}
1091 				dirty_tx++;
1092 			}
1093 
1094 #ifndef final_version
1095 			if (lp->cur_tx - dirty_tx >= TX_RING_SIZE) {
1096 				printk("out-of-sync dirty pointer, %d vs. %d, full=%s.\n",
1097 					   dirty_tx, lp->cur_tx,
1098 					   netif_queue_stopped(dev) ? "yes" : "no");
1099 				dirty_tx += TX_RING_SIZE;
1100 			}
1101 #endif
1102 
1103 			/* if the ring is no longer full, accept more packets */
1104 			if (netif_queue_stopped(dev) &&
1105 			    dirty_tx > lp->cur_tx - TX_RING_SIZE + 2)
1106 				netif_wake_queue (dev);
1107 
1108 			lp->dirty_tx = dirty_tx;
1109 		}
1110 
1111 		/* Log misc errors. */
1112 		if (csr0 & 0x4000)
1113 			dev->stats.tx_errors++; /* Tx babble. */
1114 		if (csr0 & 0x1000)
1115 			dev->stats.rx_errors++; /* Missed a Rx frame. */
1116 		if (csr0 & 0x0800) {
1117 			printk("%s: Bus master arbitration failure, status %4.4x.\n",
1118 				   dev->name, csr0);
1119 			/* Restart the chip. */
1120 			must_restart = 1;
1121 		}
1122 
1123 		if (must_restart) {
1124 			/* stop the chip to clear the error condition, then restart */
1125 			outw(0x0000, dev->base_addr + LANCE_ADDR);
1126 			outw(0x0004, dev->base_addr + LANCE_DATA);
1127 			lance_restart(dev, 0x0002, 0);
1128 		}
1129 	}
1130 
1131 	/* Clear any other interrupt, and set interrupt enable. */
1132 	outw(0x0000, dev->base_addr + LANCE_ADDR);
1133 	outw(0x7940, dev->base_addr + LANCE_DATA);
1134 
1135 	if (lance_debug > 4)
1136 		printk("%s: exiting interrupt, csr%d=%#4.4x.\n",
1137 			   dev->name, inw(ioaddr + LANCE_ADDR),
1138 			   inw(dev->base_addr + LANCE_DATA));
1139 
1140 	spin_unlock (&lp->devlock);
1141 	return IRQ_HANDLED;
1142 }
1143 
1144 static int
1145 lance_rx(struct net_device *dev)
1146 {
1147 	struct lance_private *lp = dev->ml_priv;
1148 	int entry = lp->cur_rx & RX_RING_MOD_MASK;
1149 	int i;
1150 
1151 	/* If we own the next entry, it's a new packet. Send it up. */
1152 	while (lp->rx_ring[entry].base >= 0) {
1153 		int status = lp->rx_ring[entry].base >> 24;
1154 
1155 		if (status != 0x03) {			/* There was an error. */
1156 			/* There is a tricky error noted by John Murphy,
1157 			   <murf@perftech.com> to Russ Nelson: Even with full-sized
1158 			   buffers it's possible for a jabber packet to use two
1159 			   buffers, with only the last correctly noting the error. */
1160 			if (status & 0x01)	/* Only count a general error at the */
1161 				dev->stats.rx_errors++; /* end of a packet.*/
1162 			if (status & 0x20)
1163 				dev->stats.rx_frame_errors++;
1164 			if (status & 0x10)
1165 				dev->stats.rx_over_errors++;
1166 			if (status & 0x08)
1167 				dev->stats.rx_crc_errors++;
1168 			if (status & 0x04)
1169 				dev->stats.rx_fifo_errors++;
1170 			lp->rx_ring[entry].base &= 0x03ffffff;
1171 		}
1172 		else
1173 		{
1174 			/* Malloc up new buffer, compatible with net3. */
1175 			short pkt_len = (lp->rx_ring[entry].msg_length & 0xfff)-4;
1176 			struct sk_buff *skb;
1177 
1178 			if(pkt_len<60)
1179 			{
1180 				printk("%s: Runt packet!\n",dev->name);
1181 				dev->stats.rx_errors++;
1182 			}
1183 			else
1184 			{
1185 				skb = dev_alloc_skb(pkt_len+2);
1186 				if (skb == NULL)
1187 				{
1188 					printk("%s: Memory squeeze, deferring packet.\n", dev->name);
1189 					for (i=0; i < RX_RING_SIZE; i++)
1190 						if (lp->rx_ring[(entry+i) & RX_RING_MOD_MASK].base < 0)
1191 							break;
1192 
1193 					if (i > RX_RING_SIZE -2)
1194 					{
1195 						dev->stats.rx_dropped++;
1196 						lp->rx_ring[entry].base |= 0x80000000;
1197 						lp->cur_rx++;
1198 					}
1199 					break;
1200 				}
1201 				skb_reserve(skb,2);	/* 16 byte align */
1202 				skb_put(skb,pkt_len);	/* Make room */
1203 				skb_copy_to_linear_data(skb,
1204 					(unsigned char *)isa_bus_to_virt((lp->rx_ring[entry].base & 0x00ffffff)),
1205 					pkt_len);
1206 				skb->protocol=eth_type_trans(skb,dev);
1207 				netif_rx(skb);
1208 				dev->stats.rx_packets++;
1209 				dev->stats.rx_bytes += pkt_len;
1210 			}
1211 		}
1212 		/* The docs say that the buffer length isn't touched, but Andrew Boyd
1213 		   of QNX reports that some revs of the 79C965 clear it. */
1214 		lp->rx_ring[entry].buf_length = -PKT_BUF_SZ;
1215 		lp->rx_ring[entry].base |= 0x80000000;
1216 		entry = (++lp->cur_rx) & RX_RING_MOD_MASK;
1217 	}
1218 
1219 	/* We should check that at least two ring entries are free.	 If not,
1220 	   we should free one and mark stats->rx_dropped++. */
1221 
1222 	return 0;
1223 }
1224 
1225 static int
1226 lance_close(struct net_device *dev)
1227 {
1228 	int ioaddr = dev->base_addr;
1229 	struct lance_private *lp = dev->ml_priv;
1230 
1231 	netif_stop_queue (dev);
1232 
1233 	if (chip_table[lp->chip_version].flags & LANCE_HAS_MISSED_FRAME) {
1234 		outw(112, ioaddr+LANCE_ADDR);
1235 		dev->stats.rx_missed_errors = inw(ioaddr+LANCE_DATA);
1236 	}
1237 	outw(0, ioaddr+LANCE_ADDR);
1238 
1239 	if (lance_debug > 1)
1240 		printk("%s: Shutting down ethercard, status was %2.2x.\n",
1241 			   dev->name, inw(ioaddr+LANCE_DATA));
1242 
1243 	/* We stop the LANCE here -- it occasionally polls
1244 	   memory if we don't. */
1245 	outw(0x0004, ioaddr+LANCE_DATA);
1246 
1247 	if (dev->dma != 4)
1248 	{
1249 		unsigned long flags=claim_dma_lock();
1250 		disable_dma(dev->dma);
1251 		release_dma_lock(flags);
1252 	}
1253 	free_irq(dev->irq, dev);
1254 
1255 	lance_purge_ring(dev);
1256 
1257 	return 0;
1258 }
1259 
1260 static struct net_device_stats *lance_get_stats(struct net_device *dev)
1261 {
1262 	struct lance_private *lp = dev->ml_priv;
1263 
1264 	if (chip_table[lp->chip_version].flags & LANCE_HAS_MISSED_FRAME) {
1265 		short ioaddr = dev->base_addr;
1266 		short saved_addr;
1267 		unsigned long flags;
1268 
1269 		spin_lock_irqsave(&lp->devlock, flags);
1270 		saved_addr = inw(ioaddr+LANCE_ADDR);
1271 		outw(112, ioaddr+LANCE_ADDR);
1272 		dev->stats.rx_missed_errors = inw(ioaddr+LANCE_DATA);
1273 		outw(saved_addr, ioaddr+LANCE_ADDR);
1274 		spin_unlock_irqrestore(&lp->devlock, flags);
1275 	}
1276 
1277 	return &dev->stats;
1278 }
1279 
1280 /* Set or clear the multicast filter for this adaptor.
1281  */
1282 
1283 static void set_multicast_list(struct net_device *dev)
1284 {
1285 	short ioaddr = dev->base_addr;
1286 
1287 	outw(0, ioaddr+LANCE_ADDR);
1288 	outw(0x0004, ioaddr+LANCE_DATA); /* Temporarily stop the lance.	 */
1289 
1290 	if (dev->flags&IFF_PROMISC) {
1291 		outw(15, ioaddr+LANCE_ADDR);
1292 		outw(0x8000, ioaddr+LANCE_DATA); /* Set promiscuous mode */
1293 	} else {
1294 		short multicast_table[4];
1295 		int i;
1296 		int num_addrs=netdev_mc_count(dev);
1297 		if(dev->flags&IFF_ALLMULTI)
1298 			num_addrs=1;
1299 		/* FIXIT: We don't use the multicast table, but rely on upper-layer filtering. */
1300 		memset(multicast_table, (num_addrs == 0) ? 0 : -1, sizeof(multicast_table));
1301 		for (i = 0; i < 4; i++) {
1302 			outw(8 + i, ioaddr+LANCE_ADDR);
1303 			outw(multicast_table[i], ioaddr+LANCE_DATA);
1304 		}
1305 		outw(15, ioaddr+LANCE_ADDR);
1306 		outw(0x0000, ioaddr+LANCE_DATA); /* Unset promiscuous mode */
1307 	}
1308 
1309 	lance_restart(dev, 0x0142, 0); /*  Resume normal operation */
1310 
1311 }
1312 
1313