1/*
2 * Linux ARCnet driver - device-independent routines
3 *
4 * Written 1997 by David Woodhouse.
5 * Written 1994-1999 by Avery Pennarun.
6 * Written 1999-2000 by Martin Mares <mj@ucw.cz>.
7 * Derived from skeleton.c by Donald Becker.
8 *
9 * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
10 * for sponsoring the further development of this driver.
11 *
12 * **********************
13 *
14 * The original copyright was as follows:
15 *
16 * skeleton.c Written 1993 by Donald Becker.
17 * Copyright 1993 United States Government as represented by the
18 * Director, National Security Agency. This software may only be used
19 * and distributed according to the terms of the GNU General Public License as
20 * modified by SRC, incorporated herein by reference.
21 *
22 * **********************
23 *
24 * The change log is now in a file called ChangeLog in this directory.
25 *
26 * Sources:
27 * - Crynwr arcnet.com/arcether.com packet drivers.
28 * - arcnet.c v0.00 dated 1/1/94 and apparently by
29 * Donald Becker - it didn't work :)
30 * - skeleton.c v0.05 dated 11/16/93 by Donald Becker
31 * (from Linux Kernel 1.1.45)
32 * - RFC's 1201 and 1051 - re: TCP/IP over ARCnet
33 * - The official ARCnet COM9026 data sheets (!) thanks to
34 * Ken Cornetet <kcornete@nyx10.cs.du.edu>
35 * - The official ARCnet COM20020 data sheets.
36 * - Information on some more obscure ARCnet controller chips, thanks
37 * to the nice people at SMSC.
38 * - net/inet/eth.c (from kernel 1.1.50) for header-building info.
39 * - Alternate Linux ARCnet source by V.Shergin <vsher@sao.stavropol.su>
40 * - Textual information and more alternate source from Joachim Koenig
41 * <jojo@repas.de>
42 */
43
44#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
45
46#include <linux/module.h>
47#include <linux/types.h>
48#include <linux/delay.h>
49#include <linux/netdevice.h>
50#include <linux/if_arp.h>
51#include <net/arp.h>
52#include <linux/init.h>
53#include <linux/jiffies.h>
54#include <linux/errqueue.h>
55
56#include <linux/leds.h>
57
58#include "arcdevice.h"
59#include "com9026.h"
60
61/* "do nothing" functions for protocol drivers */
62static void null_rx(struct net_device *dev, int bufnum,
63 struct archdr *pkthdr, int length);
64static int null_build_header(struct sk_buff *skb, struct net_device *dev,
65 unsigned short type, uint8_t daddr);
66static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
67 int length, int bufnum);
68
69static void arcnet_rx(struct net_device *dev, int bufnum);
70
71/* one ArcProto per possible proto ID. None of the elements of
72 * arc_proto_map are allowed to be NULL; they will get set to
73 * arc_proto_default instead. It also must not be NULL; if you would like
74 * to set it to NULL, set it to &arc_proto_null instead.
75 */
76struct ArcProto *arc_proto_map[256];
77EXPORT_SYMBOL(arc_proto_map);
78
79struct ArcProto *arc_proto_default;
80EXPORT_SYMBOL(arc_proto_default);
81
82struct ArcProto *arc_bcast_proto;
83EXPORT_SYMBOL(arc_bcast_proto);
84
85struct ArcProto *arc_raw_proto;
86EXPORT_SYMBOL(arc_raw_proto);
87
88static struct ArcProto arc_proto_null = {
89 .suffix = '?',
90 .mtu = XMTU,
91 .is_ip = 0,
92 .rx = null_rx,
93 .build_header = null_build_header,
94 .prepare_tx = null_prepare_tx,
95 .continue_tx = NULL,
96 .ack_tx = NULL
97};
98
99/* Exported function prototypes */
100int arcnet_debug = ARCNET_DEBUG;
101EXPORT_SYMBOL(arcnet_debug);
102
103/* Internal function prototypes */
104static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
105 unsigned short type, const void *daddr,
106 const void *saddr, unsigned len);
107static int go_tx(struct net_device *dev);
108
109static int debug = ARCNET_DEBUG;
110module_param(debug, int, 0);
111MODULE_DESCRIPTION("ARCnet core driver");
112MODULE_LICENSE("GPL");
113
114static int __init arcnet_init(void)
115{
116 int count;
117
118 arcnet_debug = debug;
119
120 pr_info("arcnet loaded\n");
121
122 /* initialize the protocol map */
123 arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
124 for (count = 0; count < 256; count++)
125 arc_proto_map[count] = arc_proto_default;
126
127 if (BUGLVL(D_DURING))
128 pr_info("struct sizes: %zd %zd %zd %zd %zd\n",
129 sizeof(struct arc_hardware),
130 sizeof(struct arc_rfc1201),
131 sizeof(struct arc_rfc1051),
132 sizeof(struct arc_eth_encap),
133 sizeof(struct archdr));
134
135 return 0;
136}
137
138static void __exit arcnet_exit(void)
139{
140}
141
142module_init(arcnet_init);
143module_exit(arcnet_exit);
144
145/* Dump the contents of an sk_buff */
146#if ARCNET_DEBUG_MAX & D_SKB
147void arcnet_dump_skb(struct net_device *dev,
148 struct sk_buff *skb, char *desc)
149{
150 char hdr[32];
151
152 /* dump the packet */
153 snprintf(hdr, sizeof(hdr), "%6s:%s skb->data:", dev->name, desc);
154 print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
155 16, 1, skb->data, skb->len, true);
156}
157EXPORT_SYMBOL(arcnet_dump_skb);
158#endif
159
160/* Dump the contents of an ARCnet buffer */
161#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
162static void arcnet_dump_packet(struct net_device *dev, int bufnum,
163 char *desc, int take_arcnet_lock)
164{
165 struct arcnet_local *lp = netdev_priv(dev);
166 int i, length;
167 unsigned long flags = 0;
168 static uint8_t buf[512];
169 char hdr[32];
170
171 /* hw.copy_from_card expects IRQ context so take the IRQ lock
172 * to keep it single threaded
173 */
174 if (take_arcnet_lock)
175 spin_lock_irqsave(&lp->lock, flags);
176
177 lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
178 if (take_arcnet_lock)
179 spin_unlock_irqrestore(&lp->lock, flags);
180
181 /* if the offset[0] byte is nonzero, this is a 256-byte packet */
182 length = (buf[2] ? 256 : 512);
183
184 /* dump the packet */
185 snprintf(hdr, sizeof(hdr), "%6s:%s packet dump:", dev->name, desc);
186 print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
187 16, 1, buf, length, true);
188}
189
190#else
191
192#define arcnet_dump_packet(dev, bufnum, desc, take_arcnet_lock) do { } while (0)
193
194#endif
195
196/* Trigger a LED event in response to a ARCNET device event */
197void arcnet_led_event(struct net_device *dev, enum arcnet_led_event event)
198{
199 struct arcnet_local *lp = netdev_priv(dev);
200
201 switch (event) {
202 case ARCNET_LED_EVENT_RECON:
203 led_trigger_blink_oneshot(trigger: lp->recon_led_trig, delay_on: 350, delay_off: 350, invert: 0);
204 break;
205 case ARCNET_LED_EVENT_OPEN:
206 led_trigger_event(trigger: lp->tx_led_trig, event: LED_OFF);
207 led_trigger_event(trigger: lp->recon_led_trig, event: LED_OFF);
208 break;
209 case ARCNET_LED_EVENT_STOP:
210 led_trigger_event(trigger: lp->tx_led_trig, event: LED_OFF);
211 led_trigger_event(trigger: lp->recon_led_trig, event: LED_OFF);
212 break;
213 case ARCNET_LED_EVENT_TX:
214 led_trigger_blink_oneshot(trigger: lp->tx_led_trig, delay_on: 50, delay_off: 50, invert: 0);
215 break;
216 }
217}
218EXPORT_SYMBOL_GPL(arcnet_led_event);
219
220static void arcnet_led_release(struct device *gendev, void *res)
221{
222 struct arcnet_local *lp = netdev_priv(to_net_dev(gendev));
223
224 led_trigger_unregister_simple(trigger: lp->tx_led_trig);
225 led_trigger_unregister_simple(trigger: lp->recon_led_trig);
226}
227
228/* Register ARCNET LED triggers for a arcnet device
229 *
230 * This is normally called from a driver's probe function
231 */
232void devm_arcnet_led_init(struct net_device *netdev, int index, int subid)
233{
234 struct arcnet_local *lp = netdev_priv(dev: netdev);
235 void *res;
236
237 res = devres_alloc(arcnet_led_release, 0, GFP_KERNEL);
238 if (!res) {
239 netdev_err(dev: netdev, format: "cannot register LED triggers\n");
240 return;
241 }
242
243 snprintf(buf: lp->tx_led_trig_name, size: sizeof(lp->tx_led_trig_name),
244 fmt: "arc%d-%d-tx", index, subid);
245 snprintf(buf: lp->recon_led_trig_name, size: sizeof(lp->recon_led_trig_name),
246 fmt: "arc%d-%d-recon", index, subid);
247
248 led_trigger_register_simple(name: lp->tx_led_trig_name,
249 trigger: &lp->tx_led_trig);
250 led_trigger_register_simple(name: lp->recon_led_trig_name,
251 trigger: &lp->recon_led_trig);
252
253 devres_add(dev: &netdev->dev, res);
254}
255EXPORT_SYMBOL_GPL(devm_arcnet_led_init);
256
257/* Unregister a protocol driver from the arc_proto_map. Protocol drivers
258 * are responsible for registering themselves, but the unregister routine
259 * is pretty generic so we'll do it here.
260 */
261void arcnet_unregister_proto(struct ArcProto *proto)
262{
263 int count;
264
265 if (arc_proto_default == proto)
266 arc_proto_default = &arc_proto_null;
267 if (arc_bcast_proto == proto)
268 arc_bcast_proto = arc_proto_default;
269 if (arc_raw_proto == proto)
270 arc_raw_proto = arc_proto_default;
271
272 for (count = 0; count < 256; count++) {
273 if (arc_proto_map[count] == proto)
274 arc_proto_map[count] = arc_proto_default;
275 }
276}
277EXPORT_SYMBOL(arcnet_unregister_proto);
278
279/* Add a buffer to the queue. Only the interrupt handler is allowed to do
280 * this, unless interrupts are disabled.
281 *
282 * Note: we don't check for a full queue, since there aren't enough buffers
283 * to more than fill it.
284 */
285static void release_arcbuf(struct net_device *dev, int bufnum)
286{
287 struct arcnet_local *lp = netdev_priv(dev);
288 int i;
289
290 lp->buf_queue[lp->first_free_buf++] = bufnum;
291 lp->first_free_buf %= 5;
292
293 if (BUGLVL(D_DURING)) {
294 arc_printk(D_DURING, dev, "release_arcbuf: freed #%d; buffer queue is now: ",
295 bufnum);
296 for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
297 arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
298 arc_cont(D_DURING, "\n");
299 }
300}
301
302/* Get a buffer from the queue.
303 * If this returns -1, there are no buffers available.
304 */
305static int get_arcbuf(struct net_device *dev)
306{
307 struct arcnet_local *lp = netdev_priv(dev);
308 int buf = -1, i;
309
310 if (!atomic_dec_and_test(v: &lp->buf_lock)) {
311 /* already in this function */
312 arc_printk(D_NORMAL, dev, "get_arcbuf: overlap (%d)!\n",
313 lp->buf_lock.counter);
314 } else { /* we can continue */
315 if (lp->next_buf >= 5)
316 lp->next_buf -= 5;
317
318 if (lp->next_buf == lp->first_free_buf) {
319 arc_printk(D_NORMAL, dev, "get_arcbuf: BUG: no buffers are available??\n");
320 } else {
321 buf = lp->buf_queue[lp->next_buf++];
322 lp->next_buf %= 5;
323 }
324 }
325
326 if (BUGLVL(D_DURING)) {
327 arc_printk(D_DURING, dev, "get_arcbuf: got #%d; buffer queue is now: ",
328 buf);
329 for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
330 arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
331 arc_cont(D_DURING, "\n");
332 }
333
334 atomic_inc(v: &lp->buf_lock);
335 return buf;
336}
337
338static int choose_mtu(void)
339{
340 int count, mtu = 65535;
341
342 /* choose the smallest MTU of all available encaps */
343 for (count = 0; count < 256; count++) {
344 if (arc_proto_map[count] != &arc_proto_null &&
345 arc_proto_map[count]->mtu < mtu) {
346 mtu = arc_proto_map[count]->mtu;
347 }
348 }
349
350 return mtu == 65535 ? XMTU : mtu;
351}
352
353static const struct header_ops arcnet_header_ops = {
354 .create = arcnet_header,
355};
356
357static const struct net_device_ops arcnet_netdev_ops = {
358 .ndo_open = arcnet_open,
359 .ndo_stop = arcnet_close,
360 .ndo_start_xmit = arcnet_send_packet,
361 .ndo_tx_timeout = arcnet_timeout,
362};
363
364/* Setup a struct device for ARCnet. */
365static void arcdev_setup(struct net_device *dev)
366{
367 dev->type = ARPHRD_ARCNET;
368 dev->netdev_ops = &arcnet_netdev_ops;
369 dev->header_ops = &arcnet_header_ops;
370 dev->hard_header_len = sizeof(struct arc_hardware);
371 dev->mtu = choose_mtu();
372
373 dev->addr_len = ARCNET_ALEN;
374 dev->tx_queue_len = 100;
375 dev->broadcast[0] = 0x00; /* for us, broadcasts are address 0 */
376 dev->watchdog_timeo = TX_TIMEOUT;
377
378 /* New-style flags. */
379 dev->flags = IFF_BROADCAST;
380}
381
382static void arcnet_timer(struct timer_list *t)
383{
384 struct arcnet_local *lp = from_timer(lp, t, timer);
385 struct net_device *dev = lp->dev;
386
387 spin_lock_irq(lock: &lp->lock);
388
389 if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
390 netif_carrier_on(dev);
391 netdev_info(dev, format: "link up\n");
392 }
393
394 spin_unlock_irq(lock: &lp->lock);
395}
396
397static void reset_device_work(struct work_struct *work)
398{
399 struct arcnet_local *lp;
400 struct net_device *dev;
401
402 lp = container_of(work, struct arcnet_local, reset_work);
403 dev = lp->dev;
404
405 /* Do not bring the network interface back up if an ifdown
406 * was already done.
407 */
408 if (!netif_running(dev) || !lp->reset_in_progress)
409 return;
410
411 rtnl_lock();
412
413 /* Do another check, in case of an ifdown that was triggered in
414 * the small race window between the exit condition above and
415 * acquiring RTNL.
416 */
417 if (!netif_running(dev) || !lp->reset_in_progress)
418 goto out;
419
420 dev_close(dev);
421 dev_open(dev, NULL);
422
423out:
424 rtnl_unlock();
425}
426
427static void arcnet_reply_tasklet(struct tasklet_struct *t)
428{
429 struct arcnet_local *lp = from_tasklet(lp, t, reply_tasklet);
430
431 struct sk_buff *ackskb, *skb;
432 struct sock_exterr_skb *serr;
433 struct sock *sk;
434 int ret;
435
436 local_irq_disable();
437 skb = lp->outgoing.skb;
438 if (!skb || !skb->sk) {
439 local_irq_enable();
440 return;
441 }
442
443 sock_hold(sk: skb->sk);
444 sk = skb->sk;
445 ackskb = skb_clone_sk(skb);
446 sock_put(sk: skb->sk);
447
448 if (!ackskb) {
449 local_irq_enable();
450 return;
451 }
452
453 serr = SKB_EXT_ERR(ackskb);
454 memset(serr, 0, sizeof(*serr));
455 serr->ee.ee_errno = ENOMSG;
456 serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
457 serr->ee.ee_data = skb_shinfo(skb)->tskey;
458 serr->ee.ee_info = lp->reply_status;
459
460 /* finally erasing outgoing skb */
461 dev_kfree_skb(lp->outgoing.skb);
462 lp->outgoing.skb = NULL;
463
464 ackskb->dev = lp->dev;
465
466 ret = sock_queue_err_skb(sk, skb: ackskb);
467 if (ret)
468 dev_kfree_skb_irq(skb: ackskb);
469
470 local_irq_enable();
471};
472
473struct net_device *alloc_arcdev(const char *name)
474{
475 struct net_device *dev;
476
477 dev = alloc_netdev(sizeof(struct arcnet_local),
478 name && *name ? name : "arc%d", NET_NAME_UNKNOWN,
479 arcdev_setup);
480 if (dev) {
481 struct arcnet_local *lp = netdev_priv(dev);
482
483 lp->dev = dev;
484 spin_lock_init(&lp->lock);
485 timer_setup(&lp->timer, arcnet_timer, 0);
486 INIT_WORK(&lp->reset_work, reset_device_work);
487 }
488
489 return dev;
490}
491EXPORT_SYMBOL(alloc_arcdev);
492
493void free_arcdev(struct net_device *dev)
494{
495 struct arcnet_local *lp = netdev_priv(dev);
496
497 /* Do not cancel this at ->ndo_close(), as the workqueue itself
498 * indirectly calls the ifdown path through dev_close().
499 */
500 cancel_work_sync(work: &lp->reset_work);
501 free_netdev(dev);
502}
503EXPORT_SYMBOL(free_arcdev);
504
505/* Open/initialize the board. This is called sometime after booting when
506 * the 'ifconfig' program is run.
507 *
508 * This routine should set everything up anew at each open, even registers
509 * that "should" only need to be set once at boot, so that there is
510 * non-reboot way to recover if something goes wrong.
511 */
512int arcnet_open(struct net_device *dev)
513{
514 struct arcnet_local *lp = netdev_priv(dev);
515 int count, newmtu, error;
516
517 arc_printk(D_INIT, dev, "opened.");
518
519 if (!try_module_get(module: lp->hw.owner))
520 return -ENODEV;
521
522 if (BUGLVL(D_PROTO)) {
523 arc_printk(D_PROTO, dev, "protocol map (default is '%c'): ",
524 arc_proto_default->suffix);
525 for (count = 0; count < 256; count++)
526 arc_cont(D_PROTO, "%c", arc_proto_map[count]->suffix);
527 arc_cont(D_PROTO, "\n");
528 }
529
530 tasklet_setup(t: &lp->reply_tasklet, callback: arcnet_reply_tasklet);
531
532 arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
533
534 /* try to put the card in a defined state - if it fails the first
535 * time, actually reset it.
536 */
537 error = -ENODEV;
538 if (lp->hw.reset(dev, 0) && lp->hw.reset(dev, 1))
539 goto out_module_put;
540
541 newmtu = choose_mtu();
542 if (newmtu < dev->mtu)
543 dev->mtu = newmtu;
544
545 arc_printk(D_INIT, dev, "arcnet_open: mtu: %d.\n", dev->mtu);
546
547 /* autodetect the encapsulation for each host. */
548 memset(lp->default_proto, 0, sizeof(lp->default_proto));
549
550 /* the broadcast address is special - use the 'bcast' protocol */
551 for (count = 0; count < 256; count++) {
552 if (arc_proto_map[count] == arc_bcast_proto) {
553 lp->default_proto[0] = count;
554 break;
555 }
556 }
557
558 /* initialize buffers */
559 atomic_set(v: &lp->buf_lock, i: 1);
560
561 lp->next_buf = lp->first_free_buf = 0;
562 release_arcbuf(dev, bufnum: 0);
563 release_arcbuf(dev, bufnum: 1);
564 release_arcbuf(dev, bufnum: 2);
565 release_arcbuf(dev, bufnum: 3);
566 lp->cur_tx = lp->next_tx = -1;
567 lp->cur_rx = -1;
568
569 lp->rfc1201.sequence = 1;
570
571 /* bring up the hardware driver */
572 if (lp->hw.open)
573 lp->hw.open(dev);
574
575 if (dev->dev_addr[0] == 0)
576 arc_printk(D_NORMAL, dev, "WARNING! Station address 00 is reserved for broadcasts!\n");
577 else if (dev->dev_addr[0] == 255)
578 arc_printk(D_NORMAL, dev, "WARNING! Station address FF may confuse DOS networking programs!\n");
579
580 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
581 if (lp->hw.status(dev) & RESETflag) {
582 arc_printk(D_DEBUG, dev, "%s: %d: %s\n",
583 __FILE__, __LINE__, __func__);
584 lp->hw.command(dev, CFLAGScmd | RESETclear);
585 }
586
587 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
588 /* make sure we're ready to receive IRQ's. */
589 lp->hw.intmask(dev, 0);
590 udelay(1); /* give it time to set the mask before
591 * we reset it again. (may not even be
592 * necessary)
593 */
594 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
595 lp->intmask = NORXflag | RECONflag;
596 lp->hw.intmask(dev, lp->intmask);
597 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
598
599 netif_carrier_off(dev);
600 netif_start_queue(dev);
601 mod_timer(timer: &lp->timer, expires: jiffies + msecs_to_jiffies(m: 1000));
602
603 arcnet_led_event(dev, ARCNET_LED_EVENT_OPEN);
604 return 0;
605
606 out_module_put:
607 module_put(module: lp->hw.owner);
608 return error;
609}
610EXPORT_SYMBOL(arcnet_open);
611
612/* The inverse routine to arcnet_open - shuts down the card. */
613int arcnet_close(struct net_device *dev)
614{
615 struct arcnet_local *lp = netdev_priv(dev);
616
617 arcnet_led_event(dev, ARCNET_LED_EVENT_STOP);
618 del_timer_sync(timer: &lp->timer);
619
620 netif_stop_queue(dev);
621 netif_carrier_off(dev);
622
623 tasklet_kill(t: &lp->reply_tasklet);
624
625 /* flush TX and disable RX */
626 lp->hw.intmask(dev, 0);
627 lp->hw.command(dev, NOTXcmd); /* stop transmit */
628 lp->hw.command(dev, NORXcmd); /* disable receive */
629 mdelay(1);
630
631 /* shut down the card */
632 lp->hw.close(dev);
633
634 /* reset counters */
635 lp->reset_in_progress = 0;
636
637 module_put(module: lp->hw.owner);
638 return 0;
639}
640EXPORT_SYMBOL(arcnet_close);
641
642static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
643 unsigned short type, const void *daddr,
644 const void *saddr, unsigned len)
645{
646 const struct arcnet_local *lp = netdev_priv(dev);
647 uint8_t _daddr, proto_num;
648 struct ArcProto *proto;
649
650 arc_printk(D_DURING, dev,
651 "create header from %d to %d; protocol %d (%Xh); size %u.\n",
652 saddr ? *(uint8_t *)saddr : -1,
653 daddr ? *(uint8_t *)daddr : -1,
654 type, type, len);
655
656 if (skb->len != 0 && len != skb->len)
657 arc_printk(D_NORMAL, dev, "arcnet_header: Yikes! skb->len(%d) != len(%d)!\n",
658 skb->len, len);
659
660 /* Type is host order - ? */
661 if (type == ETH_P_ARCNET) {
662 proto = arc_raw_proto;
663 arc_printk(D_DEBUG, dev, "arc_raw_proto used. proto='%c'\n",
664 proto->suffix);
665 _daddr = daddr ? *(uint8_t *)daddr : 0;
666 } else if (!daddr) {
667 /* if the dest addr isn't provided, we can't choose an
668 * encapsulation! Store the packet type (eg. ETH_P_IP)
669 * for now, and we'll push on a real header when we do
670 * rebuild_header.
671 */
672 *(uint16_t *)skb_push(skb, len: 2) = type;
673 /* XXX: Why not use skb->mac_len? */
674 if (skb->network_header - skb->mac_header != 2)
675 arc_printk(D_NORMAL, dev, "arcnet_header: Yikes! diff (%u) is not 2!\n",
676 skb->network_header - skb->mac_header);
677 return -2; /* return error -- can't transmit yet! */
678 } else {
679 /* otherwise, we can just add the header as usual. */
680 _daddr = *(uint8_t *)daddr;
681 proto_num = lp->default_proto[_daddr];
682 proto = arc_proto_map[proto_num];
683 arc_printk(D_DURING, dev, "building header for %02Xh using protocol '%c'\n",
684 proto_num, proto->suffix);
685 if (proto == &arc_proto_null && arc_bcast_proto != proto) {
686 arc_printk(D_DURING, dev, "actually, let's use '%c' instead.\n",
687 arc_bcast_proto->suffix);
688 proto = arc_bcast_proto;
689 }
690 }
691 return proto->build_header(skb, dev, type, _daddr);
692}
693
694/* Called by the kernel in order to transmit a packet. */
695netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
696 struct net_device *dev)
697{
698 struct arcnet_local *lp = netdev_priv(dev);
699 struct archdr *pkt;
700 struct arc_rfc1201 *soft;
701 struct ArcProto *proto;
702 int txbuf;
703 unsigned long flags;
704 int retval;
705
706 arc_printk(D_DURING, dev,
707 "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
708 lp->hw.status(dev), lp->cur_tx, lp->next_tx, skb->len, skb->protocol);
709
710 pkt = (struct archdr *)skb->data;
711 soft = &pkt->soft.rfc1201;
712 proto = arc_proto_map[soft->proto];
713
714 arc_printk(D_SKB_SIZE, dev, "skb: transmitting %d bytes to %02X\n",
715 skb->len, pkt->hard.dest);
716 if (BUGLVL(D_SKB))
717 arcnet_dump_skb(dev, skb, desc: "tx");
718
719 /* fits in one packet? */
720 if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
721 arc_printk(D_NORMAL, dev, "fixme: packet too large: compensating badly!\n");
722 dev_kfree_skb(skb);
723 return NETDEV_TX_OK; /* don't try again */
724 }
725
726 /* We're busy transmitting a packet... */
727 netif_stop_queue(dev);
728
729 spin_lock_irqsave(&lp->lock, flags);
730 lp->hw.intmask(dev, 0);
731 if (lp->next_tx == -1)
732 txbuf = get_arcbuf(dev);
733 else
734 txbuf = -1;
735
736 if (txbuf != -1) {
737 lp->outgoing.skb = skb;
738 if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
739 !proto->ack_tx) {
740 /* done right away and we don't want to acknowledge
741 * the package later - forget about it now
742 */
743 dev->stats.tx_bytes += skb->len;
744 } else {
745 /* do it the 'split' way */
746 lp->outgoing.proto = proto;
747 lp->outgoing.skb = skb;
748 lp->outgoing.pkt = pkt;
749
750 if (proto->continue_tx &&
751 proto->continue_tx(dev, txbuf)) {
752 arc_printk(D_NORMAL, dev,
753 "bug! continue_tx finished the first time! (proto='%c')\n",
754 proto->suffix);
755 }
756 }
757 retval = NETDEV_TX_OK;
758 lp->next_tx = txbuf;
759 } else {
760 retval = NETDEV_TX_BUSY;
761 }
762
763 arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
764 __FILE__, __LINE__, __func__, lp->hw.status(dev));
765 /* make sure we didn't ignore a TX IRQ while we were in here */
766 lp->hw.intmask(dev, 0);
767
768 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
769 lp->intmask |= TXFREEflag | EXCNAKflag;
770 lp->hw.intmask(dev, lp->intmask);
771 arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
772 __FILE__, __LINE__, __func__, lp->hw.status(dev));
773
774 arcnet_led_event(dev, ARCNET_LED_EVENT_TX);
775
776 spin_unlock_irqrestore(lock: &lp->lock, flags);
777 return retval; /* no need to try again */
778}
779EXPORT_SYMBOL(arcnet_send_packet);
780
781/* Actually start transmitting a packet that was loaded into a buffer
782 * by prepare_tx. This should _only_ be called by the interrupt handler.
783 */
784static int go_tx(struct net_device *dev)
785{
786 struct arcnet_local *lp = netdev_priv(dev);
787
788 arc_printk(D_DURING, dev, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
789 lp->hw.status(dev), lp->intmask, lp->next_tx, lp->cur_tx);
790
791 if (lp->cur_tx != -1 || lp->next_tx == -1)
792 return 0;
793
794 if (BUGLVL(D_TX))
795 arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
796
797 lp->cur_tx = lp->next_tx;
798 lp->next_tx = -1;
799
800 /* start sending */
801 lp->hw.command(dev, TXcmd | (lp->cur_tx << 3));
802
803 dev->stats.tx_packets++;
804 lp->lasttrans_dest = lp->lastload_dest;
805 lp->lastload_dest = 0;
806 lp->excnak_pending = 0;
807 lp->intmask |= TXFREEflag | EXCNAKflag;
808
809 return 1;
810}
811
812/* Called by the kernel when transmit times out */
813void arcnet_timeout(struct net_device *dev, unsigned int txqueue)
814{
815 unsigned long flags;
816 struct arcnet_local *lp = netdev_priv(dev);
817 int status = lp->hw.status(dev);
818 char *msg;
819
820 spin_lock_irqsave(&lp->lock, flags);
821 if (status & TXFREEflag) { /* transmit _DID_ finish */
822 msg = " - missed IRQ?";
823 } else {
824 msg = "";
825 dev->stats.tx_aborted_errors++;
826 lp->timed_out = 1;
827 lp->hw.command(dev, NOTXcmd | (lp->cur_tx << 3));
828 }
829 dev->stats.tx_errors++;
830
831 /* make sure we didn't miss a TX or a EXC NAK IRQ */
832 lp->hw.intmask(dev, 0);
833 lp->intmask |= TXFREEflag | EXCNAKflag;
834 lp->hw.intmask(dev, lp->intmask);
835
836 spin_unlock_irqrestore(lock: &lp->lock, flags);
837
838 if (time_after(jiffies, lp->last_timeout + 10 * HZ)) {
839 arc_printk(D_EXTRA, dev, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
840 msg, status, lp->intmask, lp->lasttrans_dest);
841 lp->last_timeout = jiffies;
842 }
843
844 if (lp->cur_tx == -1)
845 netif_wake_queue(dev);
846}
847EXPORT_SYMBOL(arcnet_timeout);
848
849/* The typical workload of the driver: Handle the network interface
850 * interrupts. Establish which device needs attention, and call the correct
851 * chipset interrupt handler.
852 */
853irqreturn_t arcnet_interrupt(int irq, void *dev_id)
854{
855 struct net_device *dev = dev_id;
856 struct arcnet_local *lp;
857 int recbuf, status, diagstatus, didsomething, boguscount;
858 unsigned long flags;
859 int retval = IRQ_NONE;
860
861 arc_printk(D_DURING, dev, "\n");
862
863 arc_printk(D_DURING, dev, "in arcnet_interrupt\n");
864
865 lp = netdev_priv(dev);
866 BUG_ON(!lp);
867
868 spin_lock_irqsave(&lp->lock, flags);
869
870 if (lp->reset_in_progress)
871 goto out;
872
873 /* RESET flag was enabled - if device is not running, we must
874 * clear it right away (but nothing else).
875 */
876 if (!netif_running(dev)) {
877 if (lp->hw.status(dev) & RESETflag)
878 lp->hw.command(dev, CFLAGScmd | RESETclear);
879 lp->hw.intmask(dev, 0);
880 spin_unlock_irqrestore(lock: &lp->lock, flags);
881 return retval;
882 }
883
884 arc_printk(D_DURING, dev, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
885 lp->hw.status(dev), lp->intmask);
886
887 boguscount = 5;
888 do {
889 status = lp->hw.status(dev);
890 diagstatus = (status >> 8) & 0xFF;
891
892 arc_printk(D_DEBUG, dev, "%s: %d: %s: status=%x\n",
893 __FILE__, __LINE__, __func__, status);
894 didsomething = 0;
895
896 /* RESET flag was enabled - card is resetting and if RX is
897 * disabled, it's NOT because we just got a packet.
898 *
899 * The card is in an undefined state.
900 * Clear it out and start over.
901 */
902 if (status & RESETflag) {
903 arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
904 status);
905
906 lp->reset_in_progress = 1;
907 netif_stop_queue(dev);
908 netif_carrier_off(dev);
909 schedule_work(work: &lp->reset_work);
910
911 /* get out of the interrupt handler! */
912 goto out;
913 }
914 /* RX is inhibited - we must have received something.
915 * Prepare to receive into the next buffer.
916 *
917 * We don't actually copy the received packet from the card
918 * until after the transmit handler runs (and possibly
919 * launches the next tx); this should improve latency slightly
920 * if we get both types of interrupts at once.
921 */
922 recbuf = -1;
923 if (status & lp->intmask & NORXflag) {
924 recbuf = lp->cur_rx;
925 arc_printk(D_DURING, dev, "Buffer #%d: receive irq (status=%Xh)\n",
926 recbuf, status);
927
928 lp->cur_rx = get_arcbuf(dev);
929 if (lp->cur_rx != -1) {
930 arc_printk(D_DURING, dev, "enabling receive to buffer #%d\n",
931 lp->cur_rx);
932 lp->hw.command(dev, RXcmd | (lp->cur_rx << 3) | RXbcasts);
933 }
934 didsomething++;
935 }
936
937 if ((diagstatus & EXCNAKflag)) {
938 arc_printk(D_DURING, dev, "EXCNAK IRQ (diagstat=%Xh)\n",
939 diagstatus);
940
941 lp->hw.command(dev, NOTXcmd); /* disable transmit */
942 lp->excnak_pending = 1;
943
944 lp->hw.command(dev, EXCNAKclear);
945 lp->intmask &= ~(EXCNAKflag);
946 didsomething++;
947 }
948
949 /* a transmit finished, and we're interested in it. */
950 if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
951 int ackstatus;
952 lp->intmask &= ~(TXFREEflag | EXCNAKflag);
953
954 if (status & TXACKflag)
955 ackstatus = 2;
956 else if (lp->excnak_pending)
957 ackstatus = 1;
958 else
959 ackstatus = 0;
960
961 arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
962 status);
963
964 if (lp->cur_tx != -1 && !lp->timed_out) {
965 if (!(status & TXACKflag)) {
966 if (lp->lasttrans_dest != 0) {
967 arc_printk(D_EXTRA, dev,
968 "transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
969 status,
970 lp->lasttrans_dest);
971 dev->stats.tx_errors++;
972 dev->stats.tx_carrier_errors++;
973 } else {
974 arc_printk(D_DURING, dev,
975 "broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
976 status,
977 lp->lasttrans_dest);
978 }
979 }
980
981 if (lp->outgoing.proto &&
982 lp->outgoing.proto->ack_tx) {
983 lp->outgoing.proto
984 ->ack_tx(dev, ackstatus);
985 }
986 lp->reply_status = ackstatus;
987 tasklet_hi_schedule(t: &lp->reply_tasklet);
988 }
989 if (lp->cur_tx != -1)
990 release_arcbuf(dev, bufnum: lp->cur_tx);
991
992 lp->cur_tx = -1;
993 lp->timed_out = 0;
994 didsomething++;
995
996 /* send another packet if there is one */
997 go_tx(dev);
998
999 /* continue a split packet, if any */
1000 if (lp->outgoing.proto &&
1001 lp->outgoing.proto->continue_tx) {
1002 int txbuf = get_arcbuf(dev);
1003
1004 if (txbuf != -1) {
1005 if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
1006 /* that was the last segment */
1007 dev->stats.tx_bytes += lp->outgoing.skb->len;
1008 if (!lp->outgoing.proto->ack_tx) {
1009 dev_kfree_skb_irq(skb: lp->outgoing.skb);
1010 lp->outgoing.proto = NULL;
1011 }
1012 }
1013 lp->next_tx = txbuf;
1014 }
1015 }
1016 /* inform upper layers of idleness, if necessary */
1017 if (lp->cur_tx == -1)
1018 netif_wake_queue(dev);
1019 }
1020 /* now process the received packet, if any */
1021 if (recbuf != -1) {
1022 if (BUGLVL(D_RX))
1023 arcnet_dump_packet(dev, recbuf, "rx irq", 0);
1024
1025 arcnet_rx(dev, bufnum: recbuf);
1026 release_arcbuf(dev, bufnum: recbuf);
1027
1028 didsomething++;
1029 }
1030 if (status & lp->intmask & RECONflag) {
1031 lp->hw.command(dev, CFLAGScmd | CONFIGclear);
1032 dev->stats.tx_carrier_errors++;
1033
1034 arc_printk(D_RECON, dev, "Network reconfiguration detected (status=%Xh)\n",
1035 status);
1036 if (netif_carrier_ok(dev)) {
1037 netif_carrier_off(dev);
1038 netdev_info(dev, format: "link down\n");
1039 }
1040 mod_timer(timer: &lp->timer, expires: jiffies + msecs_to_jiffies(m: 1000));
1041
1042 arcnet_led_event(dev, ARCNET_LED_EVENT_RECON);
1043 /* MYRECON bit is at bit 7 of diagstatus */
1044 if (diagstatus & 0x80)
1045 arc_printk(D_RECON, dev, "Put out that recon myself\n");
1046
1047 /* is the RECON info empty or old? */
1048 if (!lp->first_recon || !lp->last_recon ||
1049 time_after(jiffies, lp->last_recon + HZ * 10)) {
1050 if (lp->network_down)
1051 arc_printk(D_NORMAL, dev, "reconfiguration detected: cabling restored?\n");
1052 lp->first_recon = lp->last_recon = jiffies;
1053 lp->num_recons = lp->network_down = 0;
1054
1055 arc_printk(D_DURING, dev, "recon: clearing counters.\n");
1056 } else { /* add to current RECON counter */
1057 lp->last_recon = jiffies;
1058 lp->num_recons++;
1059
1060 arc_printk(D_DURING, dev, "recon: counter=%d, time=%lds, net=%d\n",
1061 lp->num_recons,
1062 (lp->last_recon - lp->first_recon) / HZ,
1063 lp->network_down);
1064
1065 /* if network is marked up;
1066 * and first_recon and last_recon are 60+ apart;
1067 * and the average no. of recons counted is
1068 * > RECON_THRESHOLD/min;
1069 * then print a warning message.
1070 */
1071 if (!lp->network_down &&
1072 (lp->last_recon - lp->first_recon) <= HZ * 60 &&
1073 lp->num_recons >= RECON_THRESHOLD) {
1074 lp->network_down = 1;
1075 arc_printk(D_NORMAL, dev, "many reconfigurations detected: cabling problem?\n");
1076 } else if (!lp->network_down &&
1077 lp->last_recon - lp->first_recon > HZ * 60) {
1078 /* reset counters if we've gone for
1079 * over a minute.
1080 */
1081 lp->first_recon = lp->last_recon;
1082 lp->num_recons = 1;
1083 }
1084 }
1085 } else if (lp->network_down &&
1086 time_after(jiffies, lp->last_recon + HZ * 10)) {
1087 if (lp->network_down)
1088 arc_printk(D_NORMAL, dev, "cabling restored?\n");
1089 lp->first_recon = lp->last_recon = 0;
1090 lp->num_recons = lp->network_down = 0;
1091
1092 arc_printk(D_DURING, dev, "not recon: clearing counters anyway.\n");
1093 netif_carrier_on(dev);
1094 }
1095
1096 if (didsomething)
1097 retval |= IRQ_HANDLED;
1098 } while (--boguscount && didsomething);
1099
1100 arc_printk(D_DURING, dev, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
1101 lp->hw.status(dev), boguscount);
1102 arc_printk(D_DURING, dev, "\n");
1103
1104 lp->hw.intmask(dev, 0);
1105 udelay(1);
1106 lp->hw.intmask(dev, lp->intmask);
1107
1108out:
1109 spin_unlock_irqrestore(lock: &lp->lock, flags);
1110 return retval;
1111}
1112EXPORT_SYMBOL(arcnet_interrupt);
1113
1114/* This is a generic packet receiver that calls arcnet??_rx depending on the
1115 * protocol ID found.
1116 */
1117static void arcnet_rx(struct net_device *dev, int bufnum)
1118{
1119 struct arcnet_local *lp = netdev_priv(dev);
1120 union {
1121 struct archdr pkt;
1122 char buf[512];
1123 } rxdata;
1124 struct arc_rfc1201 *soft;
1125 int length, ofs;
1126
1127 soft = &rxdata.pkt.soft.rfc1201;
1128
1129 lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);
1130 if (rxdata.pkt.hard.offset[0]) {
1131 ofs = rxdata.pkt.hard.offset[0];
1132 length = 256 - ofs;
1133 } else {
1134 ofs = rxdata.pkt.hard.offset[1];
1135 length = 512 - ofs;
1136 }
1137
1138 /* get the full header, if possible */
1139 if (sizeof(rxdata.pkt.soft) <= length) {
1140 lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));
1141 } else {
1142 memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));
1143 lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1144 }
1145
1146 arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
1147 bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);
1148
1149 dev->stats.rx_packets++;
1150 dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1151
1152 /* call the right receiver for the protocol */
1153 if (arc_proto_map[soft->proto]->is_ip) {
1154 if (BUGLVL(D_PROTO)) {
1155 struct ArcProto
1156 *oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],
1157 *newp = arc_proto_map[soft->proto];
1158
1159 if (oldp != newp) {
1160 arc_printk(D_PROTO, dev,
1161 "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
1162 soft->proto, rxdata.pkt.hard.source,
1163 newp->suffix, oldp->suffix);
1164 }
1165 }
1166
1167 /* broadcasts will always be done with the last-used encap. */
1168 lp->default_proto[0] = soft->proto;
1169
1170 /* in striking contrast, the following isn't a hack. */
1171 lp->default_proto[rxdata.pkt.hard.source] = soft->proto;
1172 }
1173 /* call the protocol-specific receiver. */
1174 arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);
1175}
1176
1177static void null_rx(struct net_device *dev, int bufnum,
1178 struct archdr *pkthdr, int length)
1179{
1180 arc_printk(D_PROTO, dev,
1181 "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1182 pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1183}
1184
1185static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1186 unsigned short type, uint8_t daddr)
1187{
1188 struct arcnet_local *lp = netdev_priv(dev);
1189
1190 arc_printk(D_PROTO, dev,
1191 "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1192 lp->default_proto[daddr]);
1193
1194 /* always fails */
1195 return 0;
1196}
1197
1198/* the "do nothing" prepare_tx function warns that there's nothing to do. */
1199static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1200 int length, int bufnum)
1201{
1202 struct arcnet_local *lp = netdev_priv(dev);
1203 struct arc_hardware newpkt;
1204
1205 arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
1206
1207 /* send a packet to myself -- will never get received, of course */
1208 newpkt.source = newpkt.dest = dev->dev_addr[0];
1209
1210 /* only one byte of actual data (and it's random) */
1211 newpkt.offset[0] = 0xFF;
1212
1213 lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1214
1215 return 1; /* done */
1216}
1217

source code of linux/drivers/net/arcnet/arcnet.c