1 /* lasi_82596.c -- driver for the intel 82596 ethernet controller, as
2    munged into HPPA boxen .
3 
4    This driver is based upon 82596.c, original credits are below...
5    but there were too many hoops which HP wants jumped through to
6    keep this code in there in a sane manner.
7 
8    3 primary sources of the mess --
9    1) hppa needs *lots* of cacheline flushing to keep this kind of
10    MMIO running.
11 
12    2) The 82596 needs to see all of its pointers as their physical
13    address.  Thus virt_to_bus/bus_to_virt are *everywhere*.
14 
15    3) The implementation HP is using seems to be significantly pickier
16    about when and how the command and RX units are started.  some
17    command ordering was changed.
18 
19    Examination of the mach driver leads one to believe that there
20    might be a saner way to pull this off...  anyone who feels like a
21    full rewrite can be my guest.
22 
23    Split 02/13/2000 Sam Creasey (sammy@oh.verio.com)
24 
25    02/01/2000  Initial modifications for parisc by Helge Deller (deller@gmx.de)
26    03/02/2000  changes for better/correct(?) cache-flushing (deller)
27 */
28 
29 /* 82596.c: A generic 82596 ethernet driver for linux. */
30 /*
31    Based on Apricot.c
32    Written 1994 by Mark Evans.
33    This driver is for the Apricot 82596 bus-master interface
34 
35    Modularised 12/94 Mark Evans
36 
37 
38    Modified to support the 82596 ethernet chips on 680x0 VME boards.
39    by Richard Hirst <richard@sleepie.demon.co.uk>
40    Renamed to be 82596.c
41 
42    980825:  Changed to receive directly in to sk_buffs which are
43    allocated at open() time.  Eliminates copy on incoming frames
44    (small ones are still copied).  Shared data now held in a
45    non-cached page, so we can run on 68060 in copyback mode.
46 
47    TBD:
48    * look at deferring rx frames rather than discarding (as per tulip)
49    * handle tx ring full as per tulip
50    * performance test to tune rx_copybreak
51 
52    Most of my modifications relate to the braindead big-endian
53    implementation by Intel.  When the i596 is operating in
54    'big-endian' mode, it thinks a 32 bit value of 0x12345678
55    should be stored as 0x56781234.  This is a real pain, when
56    you have linked lists which are shared by the 680x0 and the
57    i596.
58 
59    Driver skeleton
60    Written 1993 by Donald Becker.
61    Copyright 1993 United States Government as represented by the Director,
62    National Security Agency. This software may only be used and distributed
63    according to the terms of the GNU General Public License as modified by SRC,
64    incorporated herein by reference.
65 
66    The author may be reached as becker@scyld.com, or C/O
67    Scyld Computing Corporation, 410 Severn Ave., Suite 210, Annapolis MD 21403
68 
69  */
70 
71 #include <linux/module.h>
72 #include <linux/kernel.h>
73 #include <linux/string.h>
74 #include <linux/errno.h>
75 #include <linux/ioport.h>
76 #include <linux/interrupt.h>
77 #include <linux/delay.h>
78 #include <linux/netdevice.h>
79 #include <linux/etherdevice.h>
80 #include <linux/skbuff.h>
81 #include <linux/init.h>
82 #include <linux/types.h>
83 #include <linux/bitops.h>
84 #include <linux/dma-mapping.h>
85 #include <linux/io.h>
86 #include <linux/irq.h>
87 #include <linux/gfp.h>
88 
89 /* DEBUG flags
90  */
91 
92 #define DEB_INIT	0x0001
93 #define DEB_PROBE	0x0002
94 #define DEB_SERIOUS	0x0004
95 #define DEB_ERRORS	0x0008
96 #define DEB_MULTI	0x0010
97 #define DEB_TDR		0x0020
98 #define DEB_OPEN	0x0040
99 #define DEB_RESET	0x0080
100 #define DEB_ADDCMD	0x0100
101 #define DEB_STATUS	0x0200
102 #define DEB_STARTTX	0x0400
103 #define DEB_RXADDR	0x0800
104 #define DEB_TXADDR	0x1000
105 #define DEB_RXFRAME	0x2000
106 #define DEB_INTS	0x4000
107 #define DEB_STRUCT	0x8000
108 #define DEB_ANY		0xffff
109 
110 
111 #define DEB(x, y)	if (i596_debug & (x)) { y; }
112 
113 
114 /*
115  * The MPU_PORT command allows direct access to the 82596. With PORT access
116  * the following commands are available (p5-18). The 32-bit port command
117  * must be word-swapped with the most significant word written first.
118  * This only applies to VME boards.
119  */
120 #define PORT_RESET		0x00	/* reset 82596 */
121 #define PORT_SELFTEST		0x01	/* selftest */
122 #define PORT_ALTSCP		0x02	/* alternate SCB address */
123 #define PORT_ALTDUMP		0x03	/* Alternate DUMP address */
124 
125 static int i596_debug = (DEB_SERIOUS|DEB_PROBE);
126 
127 /* Copy frames shorter than rx_copybreak, otherwise pass on up in
128  * a full sized sk_buff.  Value of 100 stolen from tulip.c (!alpha).
129  */
130 static int rx_copybreak = 100;
131 
132 #define PKT_BUF_SZ	1536
133 #define MAX_MC_CNT	64
134 
135 #define ISCP_BUSY	0x0001
136 
137 #define I596_NULL ((u32)0xffffffff)
138 
139 #define CMD_EOL		0x8000	/* The last command of the list, stop. */
140 #define CMD_SUSP	0x4000	/* Suspend after doing cmd. */
141 #define CMD_INTR	0x2000	/* Interrupt after doing cmd. */
142 
143 #define CMD_FLEX	0x0008	/* Enable flexible memory model */
144 
145 enum commands {
146 	CmdNOp = 0, CmdSASetup = 1, CmdConfigure = 2, CmdMulticastList = 3,
147 	CmdTx = 4, CmdTDR = 5, CmdDump = 6, CmdDiagnose = 7
148 };
149 
150 #define STAT_C		0x8000	/* Set to 0 after execution */
151 #define STAT_B		0x4000	/* Command being executed */
152 #define STAT_OK		0x2000	/* Command executed ok */
153 #define STAT_A		0x1000	/* Command aborted */
154 
155 #define	 CUC_START	0x0100
156 #define	 CUC_RESUME	0x0200
157 #define	 CUC_SUSPEND    0x0300
158 #define	 CUC_ABORT	0x0400
159 #define	 RX_START	0x0010
160 #define	 RX_RESUME	0x0020
161 #define	 RX_SUSPEND	0x0030
162 #define	 RX_ABORT	0x0040
163 
164 #define TX_TIMEOUT	(HZ/20)
165 
166 
167 struct i596_reg {
168 	unsigned short porthi;
169 	unsigned short portlo;
170 	u32            ca;
171 };
172 
173 #define EOF		0x8000
174 #define SIZE_MASK	0x3fff
175 
176 struct i596_tbd {
177 	unsigned short size;
178 	unsigned short pad;
179 	u32            next;
180 	u32            data;
181 	u32 cache_pad[5];		/* Total 32 bytes... */
182 };
183 
184 /* The command structure has two 'next' pointers; v_next is the address of
185  * the next command as seen by the CPU, b_next is the address of the next
186  * command as seen by the 82596.  The b_next pointer, as used by the 82596
187  * always references the status field of the next command, rather than the
188  * v_next field, because the 82596 is unaware of v_next.  It may seem more
189  * logical to put v_next at the end of the structure, but we cannot do that
190  * because the 82596 expects other fields to be there, depending on command
191  * type.
192  */
193 
194 struct i596_cmd {
195 	struct i596_cmd *v_next;	/* Address from CPUs viewpoint */
196 	unsigned short status;
197 	unsigned short command;
198 	u32            b_next;	/* Address from i596 viewpoint */
199 };
200 
201 struct tx_cmd {
202 	struct i596_cmd cmd;
203 	u32            tbd;
204 	unsigned short size;
205 	unsigned short pad;
206 	struct sk_buff *skb;		/* So we can free it after tx */
207 	dma_addr_t dma_addr;
208 #ifdef __LP64__
209 	u32 cache_pad[6];		/* Total 64 bytes... */
210 #else
211 	u32 cache_pad[1];		/* Total 32 bytes... */
212 #endif
213 };
214 
215 struct tdr_cmd {
216 	struct i596_cmd cmd;
217 	unsigned short status;
218 	unsigned short pad;
219 };
220 
221 struct mc_cmd {
222 	struct i596_cmd cmd;
223 	short mc_cnt;
224 	char mc_addrs[MAX_MC_CNT*6];
225 };
226 
227 struct sa_cmd {
228 	struct i596_cmd cmd;
229 	char eth_addr[8];
230 };
231 
232 struct cf_cmd {
233 	struct i596_cmd cmd;
234 	char i596_config[16];
235 };
236 
237 struct i596_rfd {
238 	unsigned short stat;
239 	unsigned short cmd;
240 	u32            b_next;	/* Address from i596 viewpoint */
241 	u32            rbd;
242 	unsigned short count;
243 	unsigned short size;
244 	struct i596_rfd *v_next;	/* Address from CPUs viewpoint */
245 	struct i596_rfd *v_prev;
246 #ifndef __LP64__
247 	u32 cache_pad[2];		/* Total 32 bytes... */
248 #endif
249 };
250 
251 struct i596_rbd {
252 	/* hardware data */
253 	unsigned short count;
254 	unsigned short zero1;
255 	u32            b_next;
256 	u32            b_data;		/* Address from i596 viewpoint */
257 	unsigned short size;
258 	unsigned short zero2;
259 	/* driver data */
260 	struct sk_buff *skb;
261 	struct i596_rbd *v_next;
262 	u32            b_addr;		/* This rbd addr from i596 view */
263 	unsigned char *v_data;		/* Address from CPUs viewpoint */
264 					/* Total 32 bytes... */
265 #ifdef __LP64__
266     u32 cache_pad[4];
267 #endif
268 };
269 
270 /* These values as chosen so struct i596_dma fits in one page... */
271 
272 #define TX_RING_SIZE 32
273 #define RX_RING_SIZE 16
274 
275 struct i596_scb {
276 	unsigned short status;
277 	unsigned short command;
278 	u32           cmd;
279 	u32           rfd;
280 	u32           crc_err;
281 	u32           align_err;
282 	u32           resource_err;
283 	u32           over_err;
284 	u32           rcvdt_err;
285 	u32           short_err;
286 	unsigned short t_on;
287 	unsigned short t_off;
288 };
289 
290 struct i596_iscp {
291 	u32 stat;
292 	u32 scb;
293 };
294 
295 struct i596_scp {
296 	u32 sysbus;
297 	u32 pad;
298 	u32 iscp;
299 };
300 
301 struct i596_dma {
302 	struct i596_scp scp		        __attribute__((aligned(32)));
303 	volatile struct i596_iscp iscp		__attribute__((aligned(32)));
304 	volatile struct i596_scb scb		__attribute__((aligned(32)));
305 	struct sa_cmd sa_cmd			__attribute__((aligned(32)));
306 	struct cf_cmd cf_cmd			__attribute__((aligned(32)));
307 	struct tdr_cmd tdr_cmd			__attribute__((aligned(32)));
308 	struct mc_cmd mc_cmd			__attribute__((aligned(32)));
309 	struct i596_rfd rfds[RX_RING_SIZE]	__attribute__((aligned(32)));
310 	struct i596_rbd rbds[RX_RING_SIZE]	__attribute__((aligned(32)));
311 	struct tx_cmd tx_cmds[TX_RING_SIZE]	__attribute__((aligned(32)));
312 	struct i596_tbd tbds[TX_RING_SIZE]	__attribute__((aligned(32)));
313 };
314 
315 struct i596_private {
316 	struct i596_dma *dma;
317 	u32    stat;
318 	int last_restart;
319 	struct i596_rfd *rfd_head;
320 	struct i596_rbd *rbd_head;
321 	struct i596_cmd *cmd_tail;
322 	struct i596_cmd *cmd_head;
323 	int cmd_backlog;
324 	u32    last_cmd;
325 	int next_tx_cmd;
326 	int options;
327 	spinlock_t lock;       /* serialize access to chip */
328 	dma_addr_t dma_addr;
329 	void __iomem *mpu_port;
330 	void __iomem *ca;
331 };
332 
333 static const char init_setup[] =
334 {
335 	0x8E,		/* length, prefetch on */
336 	0xC8,		/* fifo to 8, monitor off */
337 	0x80,		/* don't save bad frames */
338 	0x2E,		/* No source address insertion, 8 byte preamble */
339 	0x00,		/* priority and backoff defaults */
340 	0x60,		/* interframe spacing */
341 	0x00,		/* slot time LSB */
342 	0xf2,		/* slot time and retries */
343 	0x00,		/* promiscuous mode */
344 	0x00,		/* collision detect */
345 	0x40,		/* minimum frame length */
346 	0xff,
347 	0x00,
348 	0x7f /*  *multi IA */ };
349 
350 static int i596_open(struct net_device *dev);
351 static int i596_start_xmit(struct sk_buff *skb, struct net_device *dev);
352 static irqreturn_t i596_interrupt(int irq, void *dev_id);
353 static int i596_close(struct net_device *dev);
354 static void i596_add_cmd(struct net_device *dev, struct i596_cmd *cmd);
355 static void i596_tx_timeout (struct net_device *dev);
356 static void print_eth(unsigned char *buf, char *str);
357 static void set_multicast_list(struct net_device *dev);
358 static inline void ca(struct net_device *dev);
359 static void mpu_port(struct net_device *dev, int c, dma_addr_t x);
360 
361 static int rx_ring_size = RX_RING_SIZE;
362 static int ticks_limit = 100;
363 static int max_cmd_backlog = TX_RING_SIZE-1;
364 
365 #ifdef CONFIG_NET_POLL_CONTROLLER
366 static void i596_poll_controller(struct net_device *dev);
367 #endif
368 
369 
370 static inline int wait_istat(struct net_device *dev, struct i596_dma *dma, int delcnt, char *str)
371 {
372 	DMA_INV(dev, &(dma->iscp), sizeof(struct i596_iscp));
373 	while (--delcnt && dma->iscp.stat) {
374 		udelay(10);
375 		DMA_INV(dev, &(dma->iscp), sizeof(struct i596_iscp));
376 	}
377 	if (!delcnt) {
378 		printk(KERN_ERR "%s: %s, iscp.stat %04x, didn't clear\n",
379 		     dev->name, str, SWAP16(dma->iscp.stat));
380 		return -1;
381 	} else
382 		return 0;
383 }
384 
385 
386 static inline int wait_cmd(struct net_device *dev, struct i596_dma *dma, int delcnt, char *str)
387 {
388 	DMA_INV(dev, &(dma->scb), sizeof(struct i596_scb));
389 	while (--delcnt && dma->scb.command) {
390 		udelay(10);
391 		DMA_INV(dev, &(dma->scb), sizeof(struct i596_scb));
392 	}
393 	if (!delcnt) {
394 		printk(KERN_ERR "%s: %s, status %4.4x, cmd %4.4x.\n",
395 		       dev->name, str,
396 		       SWAP16(dma->scb.status),
397 		       SWAP16(dma->scb.command));
398 		return -1;
399 	} else
400 		return 0;
401 }
402 
403 
404 static void i596_display_data(struct net_device *dev)
405 {
406 	struct i596_private *lp = netdev_priv(dev);
407 	struct i596_dma *dma = lp->dma;
408 	struct i596_cmd *cmd;
409 	struct i596_rfd *rfd;
410 	struct i596_rbd *rbd;
411 
412 	printk(KERN_DEBUG "lp and scp at %p, .sysbus = %08x, .iscp = %08x\n",
413 	       &dma->scp, dma->scp.sysbus, SWAP32(dma->scp.iscp));
414 	printk(KERN_DEBUG "iscp at %p, iscp.stat = %08x, .scb = %08x\n",
415 	       &dma->iscp, SWAP32(dma->iscp.stat), SWAP32(dma->iscp.scb));
416 	printk(KERN_DEBUG "scb at %p, scb.status = %04x, .command = %04x,"
417 		" .cmd = %08x, .rfd = %08x\n",
418 	       &dma->scb, SWAP16(dma->scb.status), SWAP16(dma->scb.command),
419 		SWAP16(dma->scb.cmd), SWAP32(dma->scb.rfd));
420 	printk(KERN_DEBUG "   errors: crc %x, align %x, resource %x,"
421 	       " over %x, rcvdt %x, short %x\n",
422 	       SWAP32(dma->scb.crc_err), SWAP32(dma->scb.align_err),
423 	       SWAP32(dma->scb.resource_err), SWAP32(dma->scb.over_err),
424 	       SWAP32(dma->scb.rcvdt_err), SWAP32(dma->scb.short_err));
425 	cmd = lp->cmd_head;
426 	while (cmd != NULL) {
427 		printk(KERN_DEBUG
428 		       "cmd at %p, .status = %04x, .command = %04x,"
429 		       " .b_next = %08x\n",
430 		       cmd, SWAP16(cmd->status), SWAP16(cmd->command),
431 		       SWAP32(cmd->b_next));
432 		cmd = cmd->v_next;
433 	}
434 	rfd = lp->rfd_head;
435 	printk(KERN_DEBUG "rfd_head = %p\n", rfd);
436 	do {
437 		printk(KERN_DEBUG
438 		       "   %p .stat %04x, .cmd %04x, b_next %08x, rbd %08x,"
439 		       " count %04x\n",
440 		       rfd, SWAP16(rfd->stat), SWAP16(rfd->cmd),
441 		       SWAP32(rfd->b_next), SWAP32(rfd->rbd),
442 		       SWAP16(rfd->count));
443 		rfd = rfd->v_next;
444 	} while (rfd != lp->rfd_head);
445 	rbd = lp->rbd_head;
446 	printk(KERN_DEBUG "rbd_head = %p\n", rbd);
447 	do {
448 		printk(KERN_DEBUG
449 		       "   %p .count %04x, b_next %08x, b_data %08x,"
450 		       " size %04x\n",
451 			rbd, SWAP16(rbd->count), SWAP32(rbd->b_next),
452 		       SWAP32(rbd->b_data), SWAP16(rbd->size));
453 		rbd = rbd->v_next;
454 	} while (rbd != lp->rbd_head);
455 	DMA_INV(dev, dma, sizeof(struct i596_dma));
456 }
457 
458 
459 #define virt_to_dma(lp, v) ((lp)->dma_addr + (dma_addr_t)((unsigned long)(v)-(unsigned long)((lp)->dma)))
460 
461 static inline int init_rx_bufs(struct net_device *dev)
462 {
463 	struct i596_private *lp = netdev_priv(dev);
464 	struct i596_dma *dma = lp->dma;
465 	int i;
466 	struct i596_rfd *rfd;
467 	struct i596_rbd *rbd;
468 
469 	/* First build the Receive Buffer Descriptor List */
470 
471 	for (i = 0, rbd = dma->rbds; i < rx_ring_size; i++, rbd++) {
472 		dma_addr_t dma_addr;
473 		struct sk_buff *skb;
474 
475 		skb = netdev_alloc_skb_ip_align(dev, PKT_BUF_SZ);
476 		if (skb == NULL)
477 			return -1;
478 		dma_addr = dma_map_single(dev->dev.parent, skb->data,
479 					  PKT_BUF_SZ, DMA_FROM_DEVICE);
480 		rbd->v_next = rbd+1;
481 		rbd->b_next = SWAP32(virt_to_dma(lp, rbd+1));
482 		rbd->b_addr = SWAP32(virt_to_dma(lp, rbd));
483 		rbd->skb = skb;
484 		rbd->v_data = skb->data;
485 		rbd->b_data = SWAP32(dma_addr);
486 		rbd->size = SWAP16(PKT_BUF_SZ);
487 	}
488 	lp->rbd_head = dma->rbds;
489 	rbd = dma->rbds + rx_ring_size - 1;
490 	rbd->v_next = dma->rbds;
491 	rbd->b_next = SWAP32(virt_to_dma(lp, dma->rbds));
492 
493 	/* Now build the Receive Frame Descriptor List */
494 
495 	for (i = 0, rfd = dma->rfds; i < rx_ring_size; i++, rfd++) {
496 		rfd->rbd = I596_NULL;
497 		rfd->v_next = rfd+1;
498 		rfd->v_prev = rfd-1;
499 		rfd->b_next = SWAP32(virt_to_dma(lp, rfd+1));
500 		rfd->cmd = SWAP16(CMD_FLEX);
501 	}
502 	lp->rfd_head = dma->rfds;
503 	dma->scb.rfd = SWAP32(virt_to_dma(lp, dma->rfds));
504 	rfd = dma->rfds;
505 	rfd->rbd = SWAP32(virt_to_dma(lp, lp->rbd_head));
506 	rfd->v_prev = dma->rfds + rx_ring_size - 1;
507 	rfd = dma->rfds + rx_ring_size - 1;
508 	rfd->v_next = dma->rfds;
509 	rfd->b_next = SWAP32(virt_to_dma(lp, dma->rfds));
510 	rfd->cmd = SWAP16(CMD_EOL|CMD_FLEX);
511 
512 	DMA_WBACK_INV(dev, dma, sizeof(struct i596_dma));
513 	return 0;
514 }
515 
516 static inline void remove_rx_bufs(struct net_device *dev)
517 {
518 	struct i596_private *lp = netdev_priv(dev);
519 	struct i596_rbd *rbd;
520 	int i;
521 
522 	for (i = 0, rbd = lp->dma->rbds; i < rx_ring_size; i++, rbd++) {
523 		if (rbd->skb == NULL)
524 			break;
525 		dma_unmap_single(dev->dev.parent,
526 				 (dma_addr_t)SWAP32(rbd->b_data),
527 				 PKT_BUF_SZ, DMA_FROM_DEVICE);
528 		dev_kfree_skb(rbd->skb);
529 	}
530 }
531 
532 
533 static void rebuild_rx_bufs(struct net_device *dev)
534 {
535 	struct i596_private *lp = netdev_priv(dev);
536 	struct i596_dma *dma = lp->dma;
537 	int i;
538 
539 	/* Ensure rx frame/buffer descriptors are tidy */
540 
541 	for (i = 0; i < rx_ring_size; i++) {
542 		dma->rfds[i].rbd = I596_NULL;
543 		dma->rfds[i].cmd = SWAP16(CMD_FLEX);
544 	}
545 	dma->rfds[rx_ring_size-1].cmd = SWAP16(CMD_EOL|CMD_FLEX);
546 	lp->rfd_head = dma->rfds;
547 	dma->scb.rfd = SWAP32(virt_to_dma(lp, dma->rfds));
548 	lp->rbd_head = dma->rbds;
549 	dma->rfds[0].rbd = SWAP32(virt_to_dma(lp, dma->rbds));
550 
551 	DMA_WBACK_INV(dev, dma, sizeof(struct i596_dma));
552 }
553 
554 
555 static int init_i596_mem(struct net_device *dev)
556 {
557 	struct i596_private *lp = netdev_priv(dev);
558 	struct i596_dma *dma = lp->dma;
559 	unsigned long flags;
560 
561 	mpu_port(dev, PORT_RESET, 0);
562 	udelay(100);			/* Wait 100us - seems to help */
563 
564 	/* change the scp address */
565 
566 	lp->last_cmd = jiffies;
567 
568 	dma->scp.sysbus = SYSBUS;
569 	dma->scp.iscp = SWAP32(virt_to_dma(lp, &(dma->iscp)));
570 	dma->iscp.scb = SWAP32(virt_to_dma(lp, &(dma->scb)));
571 	dma->iscp.stat = SWAP32(ISCP_BUSY);
572 	lp->cmd_backlog = 0;
573 
574 	lp->cmd_head = NULL;
575 	dma->scb.cmd = I596_NULL;
576 
577 	DEB(DEB_INIT, printk(KERN_DEBUG "%s: starting i82596.\n", dev->name));
578 
579 	DMA_WBACK(dev, &(dma->scp), sizeof(struct i596_scp));
580 	DMA_WBACK(dev, &(dma->iscp), sizeof(struct i596_iscp));
581 	DMA_WBACK(dev, &(dma->scb), sizeof(struct i596_scb));
582 
583 	mpu_port(dev, PORT_ALTSCP, virt_to_dma(lp, &dma->scp));
584 	ca(dev);
585 	if (wait_istat(dev, dma, 1000, "initialization timed out"))
586 		goto failed;
587 	DEB(DEB_INIT, printk(KERN_DEBUG
588 			     "%s: i82596 initialization successful\n",
589 			     dev->name));
590 
591 	if (request_irq(dev->irq, i596_interrupt, 0, "i82596", dev)) {
592 		printk(KERN_ERR "%s: IRQ %d not free\n", dev->name, dev->irq);
593 		goto failed;
594 	}
595 
596 	/* Ensure rx frame/buffer descriptors are tidy */
597 	rebuild_rx_bufs(dev);
598 
599 	dma->scb.command = 0;
600 	DMA_WBACK(dev, &(dma->scb), sizeof(struct i596_scb));
601 
602 	DEB(DEB_INIT, printk(KERN_DEBUG
603 			     "%s: queuing CmdConfigure\n", dev->name));
604 	memcpy(dma->cf_cmd.i596_config, init_setup, 14);
605 	dma->cf_cmd.cmd.command = SWAP16(CmdConfigure);
606 	DMA_WBACK(dev, &(dma->cf_cmd), sizeof(struct cf_cmd));
607 	i596_add_cmd(dev, &dma->cf_cmd.cmd);
608 
609 	DEB(DEB_INIT, printk(KERN_DEBUG "%s: queuing CmdSASetup\n", dev->name));
610 	memcpy(dma->sa_cmd.eth_addr, dev->dev_addr, 6);
611 	dma->sa_cmd.cmd.command = SWAP16(CmdSASetup);
612 	DMA_WBACK(dev, &(dma->sa_cmd), sizeof(struct sa_cmd));
613 	i596_add_cmd(dev, &dma->sa_cmd.cmd);
614 
615 	DEB(DEB_INIT, printk(KERN_DEBUG "%s: queuing CmdTDR\n", dev->name));
616 	dma->tdr_cmd.cmd.command = SWAP16(CmdTDR);
617 	DMA_WBACK(dev, &(dma->tdr_cmd), sizeof(struct tdr_cmd));
618 	i596_add_cmd(dev, &dma->tdr_cmd.cmd);
619 
620 	spin_lock_irqsave (&lp->lock, flags);
621 
622 	if (wait_cmd(dev, dma, 1000, "timed out waiting to issue RX_START")) {
623 		spin_unlock_irqrestore (&lp->lock, flags);
624 		goto failed_free_irq;
625 	}
626 	DEB(DEB_INIT, printk(KERN_DEBUG "%s: Issuing RX_START\n", dev->name));
627 	dma->scb.command = SWAP16(RX_START);
628 	dma->scb.rfd = SWAP32(virt_to_dma(lp, dma->rfds));
629 	DMA_WBACK(dev, &(dma->scb), sizeof(struct i596_scb));
630 
631 	ca(dev);
632 
633 	spin_unlock_irqrestore (&lp->lock, flags);
634 	if (wait_cmd(dev, dma, 1000, "RX_START not processed"))
635 		goto failed_free_irq;
636 	DEB(DEB_INIT, printk(KERN_DEBUG
637 			     "%s: Receive unit started OK\n", dev->name));
638 	return 0;
639 
640 failed_free_irq:
641 	free_irq(dev->irq, dev);
642 failed:
643 	printk(KERN_ERR "%s: Failed to initialise 82596\n", dev->name);
644 	mpu_port(dev, PORT_RESET, 0);
645 	return -1;
646 }
647 
648 
649 static inline int i596_rx(struct net_device *dev)
650 {
651 	struct i596_private *lp = netdev_priv(dev);
652 	struct i596_rfd *rfd;
653 	struct i596_rbd *rbd;
654 	int frames = 0;
655 
656 	DEB(DEB_RXFRAME, printk(KERN_DEBUG
657 				"i596_rx(), rfd_head %p, rbd_head %p\n",
658 				lp->rfd_head, lp->rbd_head));
659 
660 
661 	rfd = lp->rfd_head;		/* Ref next frame to check */
662 
663 	DMA_INV(dev, rfd, sizeof(struct i596_rfd));
664 	while (rfd->stat & SWAP16(STAT_C)) {	/* Loop while complete frames */
665 		if (rfd->rbd == I596_NULL)
666 			rbd = NULL;
667 		else if (rfd->rbd == lp->rbd_head->b_addr) {
668 			rbd = lp->rbd_head;
669 			DMA_INV(dev, rbd, sizeof(struct i596_rbd));
670 		} else {
671 			printk(KERN_ERR "%s: rbd chain broken!\n", dev->name);
672 			/* XXX Now what? */
673 			rbd = NULL;
674 		}
675 		DEB(DEB_RXFRAME, printk(KERN_DEBUG
676 				      "  rfd %p, rfd.rbd %08x, rfd.stat %04x\n",
677 				      rfd, rfd->rbd, rfd->stat));
678 
679 		if (rbd != NULL && (rfd->stat & SWAP16(STAT_OK))) {
680 			/* a good frame */
681 			int pkt_len = SWAP16(rbd->count) & 0x3fff;
682 			struct sk_buff *skb = rbd->skb;
683 			int rx_in_place = 0;
684 
685 			DEB(DEB_RXADDR, print_eth(rbd->v_data, "received"));
686 			frames++;
687 
688 			/* Check if the packet is long enough to just accept
689 			 * without copying to a properly sized skbuff.
690 			 */
691 
692 			if (pkt_len > rx_copybreak) {
693 				struct sk_buff *newskb;
694 				dma_addr_t dma_addr;
695 
696 				dma_unmap_single(dev->dev.parent,
697 						 (dma_addr_t)SWAP32(rbd->b_data),
698 						 PKT_BUF_SZ, DMA_FROM_DEVICE);
699 				/* Get fresh skbuff to replace filled one. */
700 				newskb = netdev_alloc_skb_ip_align(dev,
701 								   PKT_BUF_SZ);
702 				if (newskb == NULL) {
703 					skb = NULL;	/* drop pkt */
704 					goto memory_squeeze;
705 				}
706 
707 				/* Pass up the skb already on the Rx ring. */
708 				skb_put(skb, pkt_len);
709 				rx_in_place = 1;
710 				rbd->skb = newskb;
711 				dma_addr = dma_map_single(dev->dev.parent,
712 							  newskb->data,
713 							  PKT_BUF_SZ,
714 							  DMA_FROM_DEVICE);
715 				rbd->v_data = newskb->data;
716 				rbd->b_data = SWAP32(dma_addr);
717 				DMA_WBACK_INV(dev, rbd, sizeof(struct i596_rbd));
718 			} else
719 				skb = netdev_alloc_skb_ip_align(dev, pkt_len);
720 memory_squeeze:
721 			if (skb == NULL) {
722 				/* XXX tulip.c can defer packets here!! */
723 				printk(KERN_ERR
724 				       "%s: i596_rx Memory squeeze, dropping packet.\n",
725 				       dev->name);
726 				dev->stats.rx_dropped++;
727 			} else {
728 				if (!rx_in_place) {
729 					/* 16 byte align the data fields */
730 					dma_sync_single_for_cpu(dev->dev.parent,
731 								(dma_addr_t)SWAP32(rbd->b_data),
732 								PKT_BUF_SZ, DMA_FROM_DEVICE);
733 					memcpy(skb_put(skb, pkt_len), rbd->v_data, pkt_len);
734 					dma_sync_single_for_device(dev->dev.parent,
735 								   (dma_addr_t)SWAP32(rbd->b_data),
736 								   PKT_BUF_SZ, DMA_FROM_DEVICE);
737 				}
738 				skb->len = pkt_len;
739 				skb->protocol = eth_type_trans(skb, dev);
740 				netif_rx(skb);
741 				dev->stats.rx_packets++;
742 				dev->stats.rx_bytes += pkt_len;
743 			}
744 		} else {
745 			DEB(DEB_ERRORS, printk(KERN_DEBUG
746 					       "%s: Error, rfd.stat = 0x%04x\n",
747 					       dev->name, rfd->stat));
748 			dev->stats.rx_errors++;
749 			if (rfd->stat & SWAP16(0x0100))
750 				dev->stats.collisions++;
751 			if (rfd->stat & SWAP16(0x8000))
752 				dev->stats.rx_length_errors++;
753 			if (rfd->stat & SWAP16(0x0001))
754 				dev->stats.rx_over_errors++;
755 			if (rfd->stat & SWAP16(0x0002))
756 				dev->stats.rx_fifo_errors++;
757 			if (rfd->stat & SWAP16(0x0004))
758 				dev->stats.rx_frame_errors++;
759 			if (rfd->stat & SWAP16(0x0008))
760 				dev->stats.rx_crc_errors++;
761 			if (rfd->stat & SWAP16(0x0010))
762 				dev->stats.rx_length_errors++;
763 		}
764 
765 		/* Clear the buffer descriptor count and EOF + F flags */
766 
767 		if (rbd != NULL && (rbd->count & SWAP16(0x4000))) {
768 			rbd->count = 0;
769 			lp->rbd_head = rbd->v_next;
770 			DMA_WBACK_INV(dev, rbd, sizeof(struct i596_rbd));
771 		}
772 
773 		/* Tidy the frame descriptor, marking it as end of list */
774 
775 		rfd->rbd = I596_NULL;
776 		rfd->stat = 0;
777 		rfd->cmd = SWAP16(CMD_EOL|CMD_FLEX);
778 		rfd->count = 0;
779 
780 		/* Update record of next frame descriptor to process */
781 
782 		lp->dma->scb.rfd = rfd->b_next;
783 		lp->rfd_head = rfd->v_next;
784 		DMA_WBACK_INV(dev, rfd, sizeof(struct i596_rfd));
785 
786 		/* Remove end-of-list from old end descriptor */
787 
788 		rfd->v_prev->cmd = SWAP16(CMD_FLEX);
789 		DMA_WBACK_INV(dev, rfd->v_prev, sizeof(struct i596_rfd));
790 		rfd = lp->rfd_head;
791 		DMA_INV(dev, rfd, sizeof(struct i596_rfd));
792 	}
793 
794 	DEB(DEB_RXFRAME, printk(KERN_DEBUG "frames %d\n", frames));
795 
796 	return 0;
797 }
798 
799 
800 static inline void i596_cleanup_cmd(struct net_device *dev, struct i596_private *lp)
801 {
802 	struct i596_cmd *ptr;
803 
804 	while (lp->cmd_head != NULL) {
805 		ptr = lp->cmd_head;
806 		lp->cmd_head = ptr->v_next;
807 		lp->cmd_backlog--;
808 
809 		switch (SWAP16(ptr->command) & 0x7) {
810 		case CmdTx:
811 			{
812 				struct tx_cmd *tx_cmd = (struct tx_cmd *) ptr;
813 				struct sk_buff *skb = tx_cmd->skb;
814 				dma_unmap_single(dev->dev.parent,
815 						 tx_cmd->dma_addr,
816 						 skb->len, DMA_TO_DEVICE);
817 
818 				dev_kfree_skb(skb);
819 
820 				dev->stats.tx_errors++;
821 				dev->stats.tx_aborted_errors++;
822 
823 				ptr->v_next = NULL;
824 				ptr->b_next = I596_NULL;
825 				tx_cmd->cmd.command = 0;  /* Mark as free */
826 				break;
827 			}
828 		default:
829 			ptr->v_next = NULL;
830 			ptr->b_next = I596_NULL;
831 		}
832 		DMA_WBACK_INV(dev, ptr, sizeof(struct i596_cmd));
833 	}
834 
835 	wait_cmd(dev, lp->dma, 100, "i596_cleanup_cmd timed out");
836 	lp->dma->scb.cmd = I596_NULL;
837 	DMA_WBACK(dev, &(lp->dma->scb), sizeof(struct i596_scb));
838 }
839 
840 
841 static inline void i596_reset(struct net_device *dev, struct i596_private *lp)
842 {
843 	unsigned long flags;
844 
845 	DEB(DEB_RESET, printk(KERN_DEBUG "i596_reset\n"));
846 
847 	spin_lock_irqsave (&lp->lock, flags);
848 
849 	wait_cmd(dev, lp->dma, 100, "i596_reset timed out");
850 
851 	netif_stop_queue(dev);
852 
853 	/* FIXME: this command might cause an lpmc */
854 	lp->dma->scb.command = SWAP16(CUC_ABORT | RX_ABORT);
855 	DMA_WBACK(dev, &(lp->dma->scb), sizeof(struct i596_scb));
856 	ca(dev);
857 
858 	/* wait for shutdown */
859 	wait_cmd(dev, lp->dma, 1000, "i596_reset 2 timed out");
860 	spin_unlock_irqrestore (&lp->lock, flags);
861 
862 	i596_cleanup_cmd(dev, lp);
863 	i596_rx(dev);
864 
865 	netif_start_queue(dev);
866 	init_i596_mem(dev);
867 }
868 
869 
870 static void i596_add_cmd(struct net_device *dev, struct i596_cmd *cmd)
871 {
872 	struct i596_private *lp = netdev_priv(dev);
873 	struct i596_dma *dma = lp->dma;
874 	unsigned long flags;
875 
876 	DEB(DEB_ADDCMD, printk(KERN_DEBUG "i596_add_cmd cmd_head %p\n",
877 			       lp->cmd_head));
878 
879 	cmd->status = 0;
880 	cmd->command |= SWAP16(CMD_EOL | CMD_INTR);
881 	cmd->v_next = NULL;
882 	cmd->b_next = I596_NULL;
883 	DMA_WBACK(dev, cmd, sizeof(struct i596_cmd));
884 
885 	spin_lock_irqsave (&lp->lock, flags);
886 
887 	if (lp->cmd_head != NULL) {
888 		lp->cmd_tail->v_next = cmd;
889 		lp->cmd_tail->b_next = SWAP32(virt_to_dma(lp, &cmd->status));
890 		DMA_WBACK(dev, lp->cmd_tail, sizeof(struct i596_cmd));
891 	} else {
892 		lp->cmd_head = cmd;
893 		wait_cmd(dev, dma, 100, "i596_add_cmd timed out");
894 		dma->scb.cmd = SWAP32(virt_to_dma(lp, &cmd->status));
895 		dma->scb.command = SWAP16(CUC_START);
896 		DMA_WBACK(dev, &(dma->scb), sizeof(struct i596_scb));
897 		ca(dev);
898 	}
899 	lp->cmd_tail = cmd;
900 	lp->cmd_backlog++;
901 
902 	spin_unlock_irqrestore (&lp->lock, flags);
903 
904 	if (lp->cmd_backlog > max_cmd_backlog) {
905 		unsigned long tickssofar = jiffies - lp->last_cmd;
906 
907 		if (tickssofar < ticks_limit)
908 			return;
909 
910 		printk(KERN_ERR
911 		       "%s: command unit timed out, status resetting.\n",
912 		       dev->name);
913 #if 1
914 		i596_reset(dev, lp);
915 #endif
916 	}
917 }
918 
919 static int i596_open(struct net_device *dev)
920 {
921 	DEB(DEB_OPEN, printk(KERN_DEBUG
922 			     "%s: i596_open() irq %d.\n", dev->name, dev->irq));
923 
924 	if (init_rx_bufs(dev)) {
925 		printk(KERN_ERR "%s: Failed to init rx bufs\n", dev->name);
926 		return -EAGAIN;
927 	}
928 	if (init_i596_mem(dev)) {
929 		printk(KERN_ERR "%s: Failed to init memory\n", dev->name);
930 		goto out_remove_rx_bufs;
931 	}
932 	netif_start_queue(dev);
933 
934 	return 0;
935 
936 out_remove_rx_bufs:
937 	remove_rx_bufs(dev);
938 	return -EAGAIN;
939 }
940 
941 static void i596_tx_timeout (struct net_device *dev)
942 {
943 	struct i596_private *lp = netdev_priv(dev);
944 
945 	/* Transmitter timeout, serious problems. */
946 	DEB(DEB_ERRORS, printk(KERN_DEBUG
947 			       "%s: transmit timed out, status resetting.\n",
948 			       dev->name));
949 
950 	dev->stats.tx_errors++;
951 
952 	/* Try to restart the adaptor */
953 	if (lp->last_restart == dev->stats.tx_packets) {
954 		DEB(DEB_ERRORS, printk(KERN_DEBUG "Resetting board.\n"));
955 		/* Shutdown and restart */
956 		i596_reset (dev, lp);
957 	} else {
958 		/* Issue a channel attention signal */
959 		DEB(DEB_ERRORS, printk(KERN_DEBUG "Kicking board.\n"));
960 		lp->dma->scb.command = SWAP16(CUC_START | RX_START);
961 		DMA_WBACK_INV(dev, &(lp->dma->scb), sizeof(struct i596_scb));
962 		ca (dev);
963 		lp->last_restart = dev->stats.tx_packets;
964 	}
965 
966 	dev->trans_start = jiffies; /* prevent tx timeout */
967 	netif_wake_queue (dev);
968 }
969 
970 
971 static int i596_start_xmit(struct sk_buff *skb, struct net_device *dev)
972 {
973 	struct i596_private *lp = netdev_priv(dev);
974 	struct tx_cmd *tx_cmd;
975 	struct i596_tbd *tbd;
976 	short length = skb->len;
977 
978 	DEB(DEB_STARTTX, printk(KERN_DEBUG
979 				"%s: i596_start_xmit(%x,%p) called\n",
980 				dev->name, skb->len, skb->data));
981 
982 	if (length < ETH_ZLEN) {
983 		if (skb_padto(skb, ETH_ZLEN))
984 			return NETDEV_TX_OK;
985 		length = ETH_ZLEN;
986 	}
987 
988 	netif_stop_queue(dev);
989 
990 	tx_cmd = lp->dma->tx_cmds + lp->next_tx_cmd;
991 	tbd = lp->dma->tbds + lp->next_tx_cmd;
992 
993 	if (tx_cmd->cmd.command) {
994 		DEB(DEB_ERRORS, printk(KERN_DEBUG
995 				       "%s: xmit ring full, dropping packet.\n",
996 				       dev->name));
997 		dev->stats.tx_dropped++;
998 
999 		dev_kfree_skb(skb);
1000 	} else {
1001 		if (++lp->next_tx_cmd == TX_RING_SIZE)
1002 			lp->next_tx_cmd = 0;
1003 		tx_cmd->tbd = SWAP32(virt_to_dma(lp, tbd));
1004 		tbd->next = I596_NULL;
1005 
1006 		tx_cmd->cmd.command = SWAP16(CMD_FLEX | CmdTx);
1007 		tx_cmd->skb = skb;
1008 
1009 		tx_cmd->pad = 0;
1010 		tx_cmd->size = 0;
1011 		tbd->pad = 0;
1012 		tbd->size = SWAP16(EOF | length);
1013 
1014 		tx_cmd->dma_addr = dma_map_single(dev->dev.parent, skb->data,
1015 						  skb->len, DMA_TO_DEVICE);
1016 		tbd->data = SWAP32(tx_cmd->dma_addr);
1017 
1018 		DEB(DEB_TXADDR, print_eth(skb->data, "tx-queued"));
1019 		DMA_WBACK_INV(dev, tx_cmd, sizeof(struct tx_cmd));
1020 		DMA_WBACK_INV(dev, tbd, sizeof(struct i596_tbd));
1021 		i596_add_cmd(dev, &tx_cmd->cmd);
1022 
1023 		dev->stats.tx_packets++;
1024 		dev->stats.tx_bytes += length;
1025 	}
1026 
1027 	netif_start_queue(dev);
1028 
1029 	return NETDEV_TX_OK;
1030 }
1031 
1032 static void print_eth(unsigned char *add, char *str)
1033 {
1034 	printk(KERN_DEBUG "i596 0x%p, %pM --> %pM %02X%02X, %s\n",
1035 	       add, add + 6, add, add[12], add[13], str);
1036 }
1037 static const struct net_device_ops i596_netdev_ops = {
1038 	.ndo_open		= i596_open,
1039 	.ndo_stop		= i596_close,
1040 	.ndo_start_xmit		= i596_start_xmit,
1041 	.ndo_set_rx_mode	= set_multicast_list,
1042 	.ndo_tx_timeout		= i596_tx_timeout,
1043 	.ndo_change_mtu		= eth_change_mtu,
1044 	.ndo_validate_addr	= eth_validate_addr,
1045 	.ndo_set_mac_address	= eth_mac_addr,
1046 #ifdef CONFIG_NET_POLL_CONTROLLER
1047 	.ndo_poll_controller	= i596_poll_controller,
1048 #endif
1049 };
1050 
1051 static int __devinit i82596_probe(struct net_device *dev)
1052 {
1053 	int i;
1054 	struct i596_private *lp = netdev_priv(dev);
1055 	struct i596_dma *dma;
1056 
1057 	/* This lot is ensure things have been cache line aligned. */
1058 	BUILD_BUG_ON(sizeof(struct i596_rfd) != 32);
1059 	BUILD_BUG_ON(sizeof(struct i596_rbd) &  31);
1060 	BUILD_BUG_ON(sizeof(struct tx_cmd)   &  31);
1061 	BUILD_BUG_ON(sizeof(struct i596_tbd) != 32);
1062 #ifndef __LP64__
1063 	BUILD_BUG_ON(sizeof(struct i596_dma) > 4096);
1064 #endif
1065 
1066 	if (!dev->base_addr || !dev->irq)
1067 		return -ENODEV;
1068 
1069 	dma = (struct i596_dma *) DMA_ALLOC(dev->dev.parent,
1070 		sizeof(struct i596_dma), &lp->dma_addr, GFP_KERNEL);
1071 	if (!dma) {
1072 		printk(KERN_ERR "%s: Couldn't get shared memory\n", __FILE__);
1073 		return -ENOMEM;
1074 	}
1075 
1076 	dev->netdev_ops = &i596_netdev_ops;
1077 	dev->watchdog_timeo = TX_TIMEOUT;
1078 
1079 	memset(dma, 0, sizeof(struct i596_dma));
1080 	lp->dma = dma;
1081 
1082 	dma->scb.command = 0;
1083 	dma->scb.cmd = I596_NULL;
1084 	dma->scb.rfd = I596_NULL;
1085 	spin_lock_init(&lp->lock);
1086 
1087 	DMA_WBACK_INV(dev, dma, sizeof(struct i596_dma));
1088 
1089 	i = register_netdev(dev);
1090 	if (i) {
1091 		DMA_FREE(dev->dev.parent, sizeof(struct i596_dma),
1092 				    (void *)dma, lp->dma_addr);
1093 		return i;
1094 	}
1095 
1096 	DEB(DEB_PROBE, printk(KERN_INFO "%s: 82596 at %#3lx, %pM IRQ %d.\n",
1097 			      dev->name, dev->base_addr, dev->dev_addr,
1098 			      dev->irq));
1099 	DEB(DEB_INIT, printk(KERN_INFO
1100 			     "%s: dma at 0x%p (%d bytes), lp->scb at 0x%p\n",
1101 			     dev->name, dma, (int)sizeof(struct i596_dma),
1102 			     &dma->scb));
1103 
1104 	return 0;
1105 }
1106 
1107 #ifdef CONFIG_NET_POLL_CONTROLLER
1108 static void i596_poll_controller(struct net_device *dev)
1109 {
1110 	disable_irq(dev->irq);
1111 	i596_interrupt(dev->irq, dev);
1112 	enable_irq(dev->irq);
1113 }
1114 #endif
1115 
1116 static irqreturn_t i596_interrupt(int irq, void *dev_id)
1117 {
1118 	struct net_device *dev = dev_id;
1119 	struct i596_private *lp;
1120 	struct i596_dma *dma;
1121 	unsigned short status, ack_cmd = 0;
1122 
1123 	lp = netdev_priv(dev);
1124 	dma = lp->dma;
1125 
1126 	spin_lock (&lp->lock);
1127 
1128 	wait_cmd(dev, dma, 100, "i596 interrupt, timeout");
1129 	status = SWAP16(dma->scb.status);
1130 
1131 	DEB(DEB_INTS, printk(KERN_DEBUG
1132 			     "%s: i596 interrupt, IRQ %d, status %4.4x.\n",
1133 			dev->name, dev->irq, status));
1134 
1135 	ack_cmd = status & 0xf000;
1136 
1137 	if (!ack_cmd) {
1138 		DEB(DEB_ERRORS, printk(KERN_DEBUG
1139 				       "%s: interrupt with no events\n",
1140 				       dev->name));
1141 		spin_unlock (&lp->lock);
1142 		return IRQ_NONE;
1143 	}
1144 
1145 	if ((status & 0x8000) || (status & 0x2000)) {
1146 		struct i596_cmd *ptr;
1147 
1148 		if ((status & 0x8000))
1149 			DEB(DEB_INTS,
1150 			    printk(KERN_DEBUG
1151 				   "%s: i596 interrupt completed command.\n",
1152 				   dev->name));
1153 		if ((status & 0x2000))
1154 			DEB(DEB_INTS,
1155 			    printk(KERN_DEBUG
1156 				   "%s: i596 interrupt command unit inactive %x.\n",
1157 				   dev->name, status & 0x0700));
1158 
1159 		while (lp->cmd_head != NULL) {
1160 			DMA_INV(dev, lp->cmd_head, sizeof(struct i596_cmd));
1161 			if (!(lp->cmd_head->status & SWAP16(STAT_C)))
1162 				break;
1163 
1164 			ptr = lp->cmd_head;
1165 
1166 			DEB(DEB_STATUS,
1167 			    printk(KERN_DEBUG
1168 				   "cmd_head->status = %04x, ->command = %04x\n",
1169 				   SWAP16(lp->cmd_head->status),
1170 				   SWAP16(lp->cmd_head->command)));
1171 			lp->cmd_head = ptr->v_next;
1172 			lp->cmd_backlog--;
1173 
1174 			switch (SWAP16(ptr->command) & 0x7) {
1175 			case CmdTx:
1176 			    {
1177 				struct tx_cmd *tx_cmd = (struct tx_cmd *) ptr;
1178 				struct sk_buff *skb = tx_cmd->skb;
1179 
1180 				if (ptr->status & SWAP16(STAT_OK)) {
1181 					DEB(DEB_TXADDR,
1182 					    print_eth(skb->data, "tx-done"));
1183 				} else {
1184 					dev->stats.tx_errors++;
1185 					if (ptr->status & SWAP16(0x0020))
1186 						dev->stats.collisions++;
1187 					if (!(ptr->status & SWAP16(0x0040)))
1188 						dev->stats.tx_heartbeat_errors++;
1189 					if (ptr->status & SWAP16(0x0400))
1190 						dev->stats.tx_carrier_errors++;
1191 					if (ptr->status & SWAP16(0x0800))
1192 						dev->stats.collisions++;
1193 					if (ptr->status & SWAP16(0x1000))
1194 						dev->stats.tx_aborted_errors++;
1195 				}
1196 				dma_unmap_single(dev->dev.parent,
1197 						 tx_cmd->dma_addr,
1198 						 skb->len, DMA_TO_DEVICE);
1199 				dev_kfree_skb_irq(skb);
1200 
1201 				tx_cmd->cmd.command = 0; /* Mark free */
1202 				break;
1203 			    }
1204 			case CmdTDR:
1205 			    {
1206 				unsigned short status = SWAP16(((struct tdr_cmd *)ptr)->status);
1207 
1208 				if (status & 0x8000) {
1209 					DEB(DEB_ANY,
1210 					    printk(KERN_DEBUG "%s: link ok.\n",
1211 						   dev->name));
1212 				} else {
1213 					if (status & 0x4000)
1214 						printk(KERN_ERR
1215 						       "%s: Transceiver problem.\n",
1216 						       dev->name);
1217 					if (status & 0x2000)
1218 						printk(KERN_ERR
1219 						       "%s: Termination problem.\n",
1220 						       dev->name);
1221 					if (status & 0x1000)
1222 						printk(KERN_ERR
1223 						       "%s: Short circuit.\n",
1224 						       dev->name);
1225 
1226 					DEB(DEB_TDR,
1227 					    printk(KERN_DEBUG "%s: Time %d.\n",
1228 						   dev->name, status & 0x07ff));
1229 				}
1230 				break;
1231 			    }
1232 			case CmdConfigure:
1233 				/*
1234 				 * Zap command so set_multicast_list() know
1235 				 * it is free
1236 				 */
1237 				ptr->command = 0;
1238 				break;
1239 			}
1240 			ptr->v_next = NULL;
1241 			ptr->b_next = I596_NULL;
1242 			DMA_WBACK(dev, ptr, sizeof(struct i596_cmd));
1243 			lp->last_cmd = jiffies;
1244 		}
1245 
1246 		/* This mess is arranging that only the last of any outstanding
1247 		 * commands has the interrupt bit set.  Should probably really
1248 		 * only add to the cmd queue when the CU is stopped.
1249 		 */
1250 		ptr = lp->cmd_head;
1251 		while ((ptr != NULL) && (ptr != lp->cmd_tail)) {
1252 			struct i596_cmd *prev = ptr;
1253 
1254 			ptr->command &= SWAP16(0x1fff);
1255 			ptr = ptr->v_next;
1256 			DMA_WBACK_INV(dev, prev, sizeof(struct i596_cmd));
1257 		}
1258 
1259 		if (lp->cmd_head != NULL)
1260 			ack_cmd |= CUC_START;
1261 		dma->scb.cmd = SWAP32(virt_to_dma(lp, &lp->cmd_head->status));
1262 		DMA_WBACK_INV(dev, &dma->scb, sizeof(struct i596_scb));
1263 	}
1264 	if ((status & 0x1000) || (status & 0x4000)) {
1265 		if ((status & 0x4000))
1266 			DEB(DEB_INTS,
1267 			    printk(KERN_DEBUG
1268 				   "%s: i596 interrupt received a frame.\n",
1269 				   dev->name));
1270 		i596_rx(dev);
1271 		/* Only RX_START if stopped - RGH 07-07-96 */
1272 		if (status & 0x1000) {
1273 			if (netif_running(dev)) {
1274 				DEB(DEB_ERRORS,
1275 				    printk(KERN_DEBUG
1276 					   "%s: i596 interrupt receive unit inactive, status 0x%x\n",
1277 					   dev->name, status));
1278 				ack_cmd |= RX_START;
1279 				dev->stats.rx_errors++;
1280 				dev->stats.rx_fifo_errors++;
1281 				rebuild_rx_bufs(dev);
1282 			}
1283 		}
1284 	}
1285 	wait_cmd(dev, dma, 100, "i596 interrupt, timeout");
1286 	dma->scb.command = SWAP16(ack_cmd);
1287 	DMA_WBACK(dev, &dma->scb, sizeof(struct i596_scb));
1288 
1289 	/* DANGER: I suspect that some kind of interrupt
1290 	 acknowledgement aside from acking the 82596 might be needed
1291 	 here...  but it's running acceptably without */
1292 
1293 	ca(dev);
1294 
1295 	wait_cmd(dev, dma, 100, "i596 interrupt, exit timeout");
1296 	DEB(DEB_INTS, printk(KERN_DEBUG "%s: exiting interrupt.\n", dev->name));
1297 
1298 	spin_unlock (&lp->lock);
1299 	return IRQ_HANDLED;
1300 }
1301 
1302 static int i596_close(struct net_device *dev)
1303 {
1304 	struct i596_private *lp = netdev_priv(dev);
1305 	unsigned long flags;
1306 
1307 	netif_stop_queue(dev);
1308 
1309 	DEB(DEB_INIT,
1310 	    printk(KERN_DEBUG
1311 		   "%s: Shutting down ethercard, status was %4.4x.\n",
1312 		   dev->name, SWAP16(lp->dma->scb.status)));
1313 
1314 	spin_lock_irqsave(&lp->lock, flags);
1315 
1316 	wait_cmd(dev, lp->dma, 100, "close1 timed out");
1317 	lp->dma->scb.command = SWAP16(CUC_ABORT | RX_ABORT);
1318 	DMA_WBACK(dev, &lp->dma->scb, sizeof(struct i596_scb));
1319 
1320 	ca(dev);
1321 
1322 	wait_cmd(dev, lp->dma, 100, "close2 timed out");
1323 	spin_unlock_irqrestore(&lp->lock, flags);
1324 	DEB(DEB_STRUCT, i596_display_data(dev));
1325 	i596_cleanup_cmd(dev, lp);
1326 
1327 	free_irq(dev->irq, dev);
1328 	remove_rx_bufs(dev);
1329 
1330 	return 0;
1331 }
1332 
1333 /*
1334  *    Set or clear the multicast filter for this adaptor.
1335  */
1336 
1337 static void set_multicast_list(struct net_device *dev)
1338 {
1339 	struct i596_private *lp = netdev_priv(dev);
1340 	struct i596_dma *dma = lp->dma;
1341 	int config = 0, cnt;
1342 
1343 	DEB(DEB_MULTI,
1344 	    printk(KERN_DEBUG
1345 		   "%s: set multicast list, %d entries, promisc %s, allmulti %s\n",
1346 		   dev->name, netdev_mc_count(dev),
1347 		   dev->flags & IFF_PROMISC ? "ON" : "OFF",
1348 		   dev->flags & IFF_ALLMULTI ? "ON" : "OFF"));
1349 
1350 	if ((dev->flags & IFF_PROMISC) &&
1351 	    !(dma->cf_cmd.i596_config[8] & 0x01)) {
1352 		dma->cf_cmd.i596_config[8] |= 0x01;
1353 		config = 1;
1354 	}
1355 	if (!(dev->flags & IFF_PROMISC) &&
1356 	    (dma->cf_cmd.i596_config[8] & 0x01)) {
1357 		dma->cf_cmd.i596_config[8] &= ~0x01;
1358 		config = 1;
1359 	}
1360 	if ((dev->flags & IFF_ALLMULTI) &&
1361 	    (dma->cf_cmd.i596_config[11] & 0x20)) {
1362 		dma->cf_cmd.i596_config[11] &= ~0x20;
1363 		config = 1;
1364 	}
1365 	if (!(dev->flags & IFF_ALLMULTI) &&
1366 	    !(dma->cf_cmd.i596_config[11] & 0x20)) {
1367 		dma->cf_cmd.i596_config[11] |= 0x20;
1368 		config = 1;
1369 	}
1370 	if (config) {
1371 		if (dma->cf_cmd.cmd.command)
1372 			printk(KERN_INFO
1373 			       "%s: config change request already queued\n",
1374 			       dev->name);
1375 		else {
1376 			dma->cf_cmd.cmd.command = SWAP16(CmdConfigure);
1377 			DMA_WBACK_INV(dev, &dma->cf_cmd, sizeof(struct cf_cmd));
1378 			i596_add_cmd(dev, &dma->cf_cmd.cmd);
1379 		}
1380 	}
1381 
1382 	cnt = netdev_mc_count(dev);
1383 	if (cnt > MAX_MC_CNT) {
1384 		cnt = MAX_MC_CNT;
1385 		printk(KERN_NOTICE "%s: Only %d multicast addresses supported",
1386 			dev->name, cnt);
1387 	}
1388 
1389 	if (!netdev_mc_empty(dev)) {
1390 		struct netdev_hw_addr *ha;
1391 		unsigned char *cp;
1392 		struct mc_cmd *cmd;
1393 
1394 		cmd = &dma->mc_cmd;
1395 		cmd->cmd.command = SWAP16(CmdMulticastList);
1396 		cmd->mc_cnt = SWAP16(netdev_mc_count(dev) * 6);
1397 		cp = cmd->mc_addrs;
1398 		netdev_for_each_mc_addr(ha, dev) {
1399 			if (!cnt--)
1400 				break;
1401 			memcpy(cp, ha->addr, 6);
1402 			if (i596_debug > 1)
1403 				DEB(DEB_MULTI,
1404 				    printk(KERN_DEBUG
1405 					   "%s: Adding address %pM\n",
1406 					   dev->name, cp));
1407 			cp += 6;
1408 		}
1409 		DMA_WBACK_INV(dev, &dma->mc_cmd, sizeof(struct mc_cmd));
1410 		i596_add_cmd(dev, &cmd->cmd);
1411 	}
1412 }
1413