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

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