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#include <linux/workqueue.h>
58
59#include "arcdevice.h"
60#include "com9026.h"
61
62/* "do nothing" functions for protocol drivers */
63static void null_rx(struct net_device *dev, int bufnum,
64 struct archdr *pkthdr, int length);
65static int null_build_header(struct sk_buff *skb, struct net_device *dev,
66 unsigned short type, uint8_t daddr);
67static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
68 int length, int bufnum);
69
70static void arcnet_rx(struct net_device *dev, int bufnum);
71
72/* one ArcProto per possible proto ID. None of the elements of
73 * arc_proto_map are allowed to be NULL; they will get set to
74 * arc_proto_default instead. It also must not be NULL; if you would like
75 * to set it to NULL, set it to &arc_proto_null instead.
76 */
77struct ArcProto *arc_proto_map[256];
78EXPORT_SYMBOL(arc_proto_map);
79
80struct ArcProto *arc_proto_default;
81EXPORT_SYMBOL(arc_proto_default);
82
83struct ArcProto *arc_bcast_proto;
84EXPORT_SYMBOL(arc_bcast_proto);
85
86struct ArcProto *arc_raw_proto;
87EXPORT_SYMBOL(arc_raw_proto);
88
89static struct ArcProto arc_proto_null = {
90 .suffix = '?',
91 .mtu = XMTU,
92 .is_ip = 0,
93 .rx = null_rx,
94 .build_header = null_build_header,
95 .prepare_tx = null_prepare_tx,
96 .continue_tx = NULL,
97 .ack_tx = NULL
98};
99
100/* Exported function prototypes */
101int arcnet_debug = ARCNET_DEBUG;
102EXPORT_SYMBOL(arcnet_debug);
103
104/* Internal function prototypes */
105static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
106 unsigned short type, const void *daddr,
107 const void *saddr, unsigned len);
108static int go_tx(struct net_device *dev);
109
110static int debug = ARCNET_DEBUG;
111module_param(debug, int, 0);
112MODULE_DESCRIPTION("ARCnet core driver");
113MODULE_LICENSE("GPL");
114
115static int __init arcnet_init(void)
116{
117 int count;
118
119 arcnet_debug = debug;
120
121 pr_info("arcnet loaded\n");
122
123 /* initialize the protocol map */
124 arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
125 for (count = 0; count < 256; count++)
126 arc_proto_map[count] = arc_proto_default;
127
128 if (BUGLVL(D_DURING))
129 pr_info("struct sizes: %zd %zd %zd %zd %zd\n",
130 sizeof(struct arc_hardware),
131 sizeof(struct arc_rfc1201),
132 sizeof(struct arc_rfc1051),
133 sizeof(struct arc_eth_encap),
134 sizeof(struct archdr));
135
136 return 0;
137}
138
139static void __exit arcnet_exit(void)
140{
141}
142
143module_init(arcnet_init);
144module_exit(arcnet_exit);
145
146/* Dump the contents of an sk_buff */
147#if ARCNET_DEBUG_MAX & D_SKB
148void arcnet_dump_skb(struct net_device *dev,
149 struct sk_buff *skb, char *desc)
150{
151 char hdr[32];
152
153 /* dump the packet */
154 snprintf(hdr, sizeof(hdr), "%6s:%s skb->data:", dev->name, desc);
155 print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
156 16, 1, skb->data, skb->len, true);
157}
158EXPORT_SYMBOL(arcnet_dump_skb);
159#endif
160
161/* Dump the contents of an ARCnet buffer */
162#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
163static void arcnet_dump_packet(struct net_device *dev, int bufnum,
164 char *desc, int take_arcnet_lock)
165{
166 struct arcnet_local *lp = netdev_priv(dev);
167 int i, length;
168 unsigned long flags = 0;
169 static uint8_t buf[512];
170 char hdr[32];
171
172 /* hw.copy_from_card expects IRQ context so take the IRQ lock
173 * to keep it single threaded
174 */
175 if (take_arcnet_lock)
176 spin_lock_irqsave(&lp->lock, flags);
177
178 lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
179 if (take_arcnet_lock)
180 spin_unlock_irqrestore(&lp->lock, flags);
181
182 /* if the offset[0] byte is nonzero, this is a 256-byte packet */
183 length = (buf[2] ? 256 : 512);
184
185 /* dump the packet */
186 snprintf(hdr, sizeof(hdr), "%6s:%s packet dump:", dev->name, desc);
187 print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
188 16, 1, buf, length, true);
189}
190
191#else
192
193#define arcnet_dump_packet(dev, bufnum, desc, take_arcnet_lock) do { } while (0)
194
195#endif
196
197/* Trigger a LED event in response to a ARCNET device event */
198void arcnet_led_event(struct net_device *dev, enum arcnet_led_event event)
199{
200 struct arcnet_local *lp = netdev_priv(dev);
201
202 switch (event) {
203 case ARCNET_LED_EVENT_RECON:
204 led_trigger_blink_oneshot(trigger: lp->recon_led_trig, delay_on: 350, delay_off: 350, invert: 0);
205 break;
206 case ARCNET_LED_EVENT_OPEN:
207 led_trigger_event(trigger: lp->tx_led_trig, event: LED_OFF);
208 led_trigger_event(trigger: lp->recon_led_trig, event: LED_OFF);
209 break;
210 case ARCNET_LED_EVENT_STOP:
211 led_trigger_event(trigger: lp->tx_led_trig, event: LED_OFF);
212 led_trigger_event(trigger: lp->recon_led_trig, event: LED_OFF);
213 break;
214 case ARCNET_LED_EVENT_TX:
215 led_trigger_blink_oneshot(trigger: lp->tx_led_trig, delay_on: 50, delay_off: 50, invert: 0);
216 break;
217 }
218}
219EXPORT_SYMBOL_GPL(arcnet_led_event);
220
221static void arcnet_led_release(struct device *gendev, void *res)
222{
223 struct arcnet_local *lp = netdev_priv(to_net_dev(gendev));
224
225 led_trigger_unregister_simple(trigger: lp->tx_led_trig);
226 led_trigger_unregister_simple(trigger: lp->recon_led_trig);
227}
228
229/* Register ARCNET LED triggers for a arcnet device
230 *
231 * This is normally called from a driver's probe function
232 */
233void devm_arcnet_led_init(struct net_device *netdev, int index, int subid)
234{
235 struct arcnet_local *lp = netdev_priv(dev: netdev);
236 void *res;
237
238 res = devres_alloc(arcnet_led_release, 0, GFP_KERNEL);
239 if (!res) {
240 netdev_err(dev: netdev, format: "cannot register LED triggers\n");
241 return;
242 }
243
244 snprintf(buf: lp->tx_led_trig_name, size: sizeof(lp->tx_led_trig_name),
245 fmt: "arc%d-%d-tx", index, subid);
246 snprintf(buf: lp->recon_led_trig_name, size: sizeof(lp->recon_led_trig_name),
247 fmt: "arc%d-%d-recon", index, subid);
248
249 led_trigger_register_simple(name: lp->tx_led_trig_name,
250 trigger: &lp->tx_led_trig);
251 led_trigger_register_simple(name: lp->recon_led_trig_name,
252 trigger: &lp->recon_led_trig);
253
254 devres_add(dev: &netdev->dev, res);
255}
256EXPORT_SYMBOL_GPL(devm_arcnet_led_init);
257
258/* Unregister a protocol driver from the arc_proto_map. Protocol drivers
259 * are responsible for registering themselves, but the unregister routine
260 * is pretty generic so we'll do it here.
261 */
262void arcnet_unregister_proto(struct ArcProto *proto)
263{
264 int count;
265
266 if (arc_proto_default == proto)
267 arc_proto_default = &arc_proto_null;
268 if (arc_bcast_proto == proto)
269 arc_bcast_proto = arc_proto_default;
270 if (arc_raw_proto == proto)
271 arc_raw_proto = arc_proto_default;
272
273 for (count = 0; count < 256; count++) {
274 if (arc_proto_map[count] == proto)
275 arc_proto_map[count] = arc_proto_default;
276 }
277}
278EXPORT_SYMBOL(arcnet_unregister_proto);
279
280/* Add a buffer to the queue. Only the interrupt handler is allowed to do
281 * this, unless interrupts are disabled.
282 *
283 * Note: we don't check for a full queue, since there aren't enough buffers
284 * to more than fill it.
285 */
286static void release_arcbuf(struct net_device *dev, int bufnum)
287{
288 struct arcnet_local *lp = netdev_priv(dev);
289 int i;
290
291 lp->buf_queue[lp->first_free_buf++] = bufnum;
292 lp->first_free_buf %= 5;
293
294 if (BUGLVL(D_DURING)) {
295 arc_printk(D_DURING, dev, "release_arcbuf: freed #%d; buffer queue is now: ",
296 bufnum);
297 for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
298 arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
299 arc_cont(D_DURING, "\n");
300 }
301}
302
303/* Get a buffer from the queue.
304 * If this returns -1, there are no buffers available.
305 */
306static int get_arcbuf(struct net_device *dev)
307{
308 struct arcnet_local *lp = netdev_priv(dev);
309 int buf = -1, i;
310
311 if (!atomic_dec_and_test(v: &lp->buf_lock)) {
312 /* already in this function */
313 arc_printk(D_NORMAL, dev, "get_arcbuf: overlap (%d)!\n",
314 lp->buf_lock.counter);
315 } else { /* we can continue */
316 if (lp->next_buf >= 5)
317 lp->next_buf -= 5;
318
319 if (lp->next_buf == lp->first_free_buf) {
320 arc_printk(D_NORMAL, dev, "get_arcbuf: BUG: no buffers are available??\n");
321 } else {
322 buf = lp->buf_queue[lp->next_buf++];
323 lp->next_buf %= 5;
324 }
325 }
326
327 if (BUGLVL(D_DURING)) {
328 arc_printk(D_DURING, dev, "get_arcbuf: got #%d; buffer queue is now: ",
329 buf);
330 for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
331 arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
332 arc_cont(D_DURING, "\n");
333 }
334
335 atomic_inc(v: &lp->buf_lock);
336 return buf;
337}
338
339static int choose_mtu(void)
340{
341 int count, mtu = 65535;
342
343 /* choose the smallest MTU of all available encaps */
344 for (count = 0; count < 256; count++) {
345 if (arc_proto_map[count] != &arc_proto_null &&
346 arc_proto_map[count]->mtu < mtu) {
347 mtu = arc_proto_map[count]->mtu;
348 }
349 }
350
351 return mtu == 65535 ? XMTU : mtu;
352}
353
354static const struct header_ops arcnet_header_ops = {
355 .create = arcnet_header,
356};
357
358static const struct net_device_ops arcnet_netdev_ops = {
359 .ndo_open = arcnet_open,
360 .ndo_stop = arcnet_close,
361 .ndo_start_xmit = arcnet_send_packet,
362 .ndo_tx_timeout = arcnet_timeout,
363};
364
365/* Setup a struct device for ARCnet. */
366static void arcdev_setup(struct net_device *dev)
367{
368 dev->type = ARPHRD_ARCNET;
369 dev->netdev_ops = &arcnet_netdev_ops;
370 dev->header_ops = &arcnet_header_ops;
371 dev->hard_header_len = sizeof(struct arc_hardware);
372 dev->mtu = choose_mtu();
373
374 dev->addr_len = ARCNET_ALEN;
375 dev->tx_queue_len = 100;
376 dev->broadcast[0] = 0x00; /* for us, broadcasts are address 0 */
377 dev->watchdog_timeo = TX_TIMEOUT;
378
379 /* New-style flags. */
380 dev->flags = IFF_BROADCAST;
381}
382
383static void arcnet_timer(struct timer_list *t)
384{
385 struct arcnet_local *lp = timer_container_of(lp, t, timer);
386 struct net_device *dev = lp->dev;
387
388 spin_lock_irq(lock: &lp->lock);
389
390 if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
391 netif_carrier_on(dev);
392 netdev_info(dev, format: "link up\n");
393 }
394
395 spin_unlock_irq(lock: &lp->lock);
396}
397
398static void reset_device_work(struct work_struct *work)
399{
400 struct arcnet_local *lp;
401 struct net_device *dev;
402
403 lp = container_of(work, struct arcnet_local, reset_work);
404 dev = lp->dev;
405
406 /* Do not bring the network interface back up if an ifdown
407 * was already done.
408 */
409 if (!netif_running(dev) || !lp->reset_in_progress)
410 return;
411
412 rtnl_lock();
413
414 /* Do another check, in case of an ifdown that was triggered in
415 * the small race window between the exit condition above and
416 * acquiring RTNL.
417 */
418 if (!netif_running(dev) || !lp->reset_in_progress)
419 goto out;
420
421 dev_close(dev);
422 dev_open(dev, NULL);
423
424out:
425 rtnl_unlock();
426}
427
428static void arcnet_reply_work(struct work_struct *t)
429{
430 struct arcnet_local *lp = from_work(lp, t, reply_work);
431
432 struct sk_buff *ackskb, *skb;
433 struct sock_exterr_skb *serr;
434 struct sock *sk;
435 int ret;
436
437 local_irq_disable();
438 skb = lp->outgoing.skb;
439 if (!skb || !skb->sk) {
440 local_irq_enable();
441 return;
442 }
443
444 sock_hold(sk: skb->sk);
445 sk = skb->sk;
446 ackskb = skb_clone_sk(skb);
447 sock_put(sk: skb->sk);
448
449 if (!ackskb) {
450 local_irq_enable();
451 return;
452 }
453
454 serr = SKB_EXT_ERR(ackskb);
455 memset(serr, 0, sizeof(*serr));
456 serr->ee.ee_errno = ENOMSG;
457 serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
458 serr->ee.ee_data = skb_shinfo(skb)->tskey;
459 serr->ee.ee_info = lp->reply_status;
460
461 /* finally erasing outgoing skb */
462 dev_kfree_skb(lp->outgoing.skb);
463 lp->outgoing.skb = NULL;
464
465 ackskb->dev = lp->dev;
466
467 ret = sock_queue_err_skb(sk, skb: ackskb);
468 if (ret)
469 dev_kfree_skb_irq(skb: ackskb);
470
471 local_irq_enable();
472};
473
474struct net_device *alloc_arcdev(const char *name)
475{
476 struct net_device *dev;
477
478 dev = alloc_netdev(sizeof(struct arcnet_local),
479 name && *name ? name : "arc%d", NET_NAME_UNKNOWN,
480 arcdev_setup);
481 if (dev) {
482 struct arcnet_local *lp = netdev_priv(dev);
483
484 lp->dev = dev;
485 spin_lock_init(&lp->lock);
486 timer_setup(&lp->timer, arcnet_timer, 0);
487 INIT_WORK(&lp->reset_work, reset_device_work);
488 }
489
490 return dev;
491}
492EXPORT_SYMBOL(alloc_arcdev);
493
494void free_arcdev(struct net_device *dev)
495{
496 struct arcnet_local *lp = netdev_priv(dev);
497
498 /* Do not cancel this at ->ndo_close(), as the workqueue itself
499 * indirectly calls the ifdown path through dev_close().
500 */
501 cancel_work_sync(work: &lp->reset_work);
502 free_netdev(dev);
503}
504EXPORT_SYMBOL(free_arcdev);
505
506/* Open/initialize the board. This is called sometime after booting when
507 * the 'ifconfig' program is run.
508 *
509 * This routine should set everything up anew at each open, even registers
510 * that "should" only need to be set once at boot, so that there is
511 * non-reboot way to recover if something goes wrong.
512 */
513int arcnet_open(struct net_device *dev)
514{
515 struct arcnet_local *lp = netdev_priv(dev);
516 int count, newmtu, error;
517
518 arc_printk(D_INIT, dev, "opened.");
519
520 if (!try_module_get(module: lp->hw.owner))
521 return -ENODEV;
522
523 if (BUGLVL(D_PROTO)) {
524 arc_printk(D_PROTO, dev, "protocol map (default is '%c'): ",
525 arc_proto_default->suffix);
526 for (count = 0; count < 256; count++)
527 arc_cont(D_PROTO, "%c", arc_proto_map[count]->suffix);
528 arc_cont(D_PROTO, "\n");
529 }
530
531 INIT_WORK(&lp->reply_work, arcnet_reply_work);
532
533 arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
534
535 /* try to put the card in a defined state - if it fails the first
536 * time, actually reset it.
537 */
538 error = -ENODEV;
539 if (lp->hw.reset(dev, 0) && lp->hw.reset(dev, 1))
540 goto out_module_put;
541
542 newmtu = choose_mtu();
543 if (newmtu < dev->mtu)
544 dev->mtu = newmtu;
545
546 arc_printk(D_INIT, dev, "arcnet_open: mtu: %d.\n", dev->mtu);
547
548 /* autodetect the encapsulation for each host. */
549 memset(lp->default_proto, 0, sizeof(lp->default_proto));
550
551 /* the broadcast address is special - use the 'bcast' protocol */
552 for (count = 0; count < 256; count++) {
553 if (arc_proto_map[count] == arc_bcast_proto) {
554 lp->default_proto[0] = count;
555 break;
556 }
557 }
558
559 /* initialize buffers */
560 atomic_set(v: &lp->buf_lock, i: 1);
561
562 lp->next_buf = lp->first_free_buf = 0;
563 release_arcbuf(dev, bufnum: 0);
564 release_arcbuf(dev, bufnum: 1);
565 release_arcbuf(dev, bufnum: 2);
566 release_arcbuf(dev, bufnum: 3);
567 lp->cur_tx = lp->next_tx = -1;
568 lp->cur_rx = -1;
569
570 lp->rfc1201.sequence = 1;
571
572 /* bring up the hardware driver */
573 if (lp->hw.open)
574 lp->hw.open(dev);
575
576 if (dev->dev_addr[0] == 0)
577 arc_printk(D_NORMAL, dev, "WARNING! Station address 00 is reserved for broadcasts!\n");
578 else if (dev->dev_addr[0] == 255)
579 arc_printk(D_NORMAL, dev, "WARNING! Station address FF may confuse DOS networking programs!\n");
580
581 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
582 if (lp->hw.status(dev) & RESETflag) {
583 arc_printk(D_DEBUG, dev, "%s: %d: %s\n",
584 __FILE__, __LINE__, __func__);
585 lp->hw.command(dev, CFLAGScmd | RESETclear);
586 }
587
588 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
589 /* make sure we're ready to receive IRQ's. */
590 lp->hw.intmask(dev, 0);
591 udelay(usec: 1); /* give it time to set the mask before
592 * we reset it again. (may not even be
593 * necessary)
594 */
595 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
596 lp->intmask = NORXflag | RECONflag;
597 lp->hw.intmask(dev, lp->intmask);
598 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
599
600 netif_carrier_off(dev);
601 netif_start_queue(dev);
602 mod_timer(timer: &lp->timer, expires: jiffies + msecs_to_jiffies(m: 1000));
603
604 arcnet_led_event(dev, ARCNET_LED_EVENT_OPEN);
605 return 0;
606
607 out_module_put:
608 module_put(module: lp->hw.owner);
609 return error;
610}
611EXPORT_SYMBOL(arcnet_open);
612
613/* The inverse routine to arcnet_open - shuts down the card. */
614int arcnet_close(struct net_device *dev)
615{
616 struct arcnet_local *lp = netdev_priv(dev);
617
618 arcnet_led_event(dev, ARCNET_LED_EVENT_STOP);
619 timer_delete_sync(timer: &lp->timer);
620
621 netif_stop_queue(dev);
622 netif_carrier_off(dev);
623
624 cancel_work_sync(work: &lp->reply_work);
625
626 /* flush TX and disable RX */
627 lp->hw.intmask(dev, 0);
628 lp->hw.command(dev, NOTXcmd); /* stop transmit */
629 lp->hw.command(dev, NORXcmd); /* disable receive */
630 mdelay(1);
631
632 /* shut down the card */
633 lp->hw.close(dev);
634
635 /* reset counters */
636 lp->reset_in_progress = 0;
637
638 module_put(module: lp->hw.owner);
639 return 0;
640}
641EXPORT_SYMBOL(arcnet_close);
642
643static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
644 unsigned short type, const void *daddr,
645 const void *saddr, unsigned len)
646{
647 const struct arcnet_local *lp = netdev_priv(dev);
648 uint8_t _daddr, proto_num;
649 struct ArcProto *proto;
650
651 arc_printk(D_DURING, dev,
652 "create header from %d to %d; protocol %d (%Xh); size %u.\n",
653 saddr ? *(uint8_t *)saddr : -1,
654 daddr ? *(uint8_t *)daddr : -1,
655 type, type, len);
656
657 if (skb->len != 0 && len != skb->len)
658 arc_printk(D_NORMAL, dev, "arcnet_header: Yikes! skb->len(%d) != len(%d)!\n",
659 skb->len, len);
660
661 /* Type is host order - ? */
662 if (type == ETH_P_ARCNET) {
663 proto = arc_raw_proto;
664 arc_printk(D_DEBUG, dev, "arc_raw_proto used. proto='%c'\n",
665 proto->suffix);
666 _daddr = daddr ? *(uint8_t *)daddr : 0;
667 } else if (!daddr) {
668 /* if the dest addr isn't provided, we can't choose an
669 * encapsulation! Store the packet type (eg. ETH_P_IP)
670 * for now, and we'll push on a real header when we do
671 * rebuild_header.
672 */
673 *(uint16_t *)skb_push(skb, len: 2) = type;
674 /* XXX: Why not use skb->mac_len? */
675 if (skb->network_header - skb->mac_header != 2)
676 arc_printk(D_NORMAL, dev, "arcnet_header: Yikes! diff (%u) is not 2!\n",
677 skb->network_header - skb->mac_header);
678 return -2; /* return error -- can't transmit yet! */
679 } else {
680 /* otherwise, we can just add the header as usual. */
681 _daddr = *(uint8_t *)daddr;
682 proto_num = lp->default_proto[_daddr];
683 proto = arc_proto_map[proto_num];
684 arc_printk(D_DURING, dev, "building header for %02Xh using protocol '%c'\n",
685 proto_num, proto->suffix);
686 if (proto == &arc_proto_null && arc_bcast_proto != proto) {
687 arc_printk(D_DURING, dev, "actually, let's use '%c' instead.\n",
688 arc_bcast_proto->suffix);
689 proto = arc_bcast_proto;
690 }
691 }
692 return proto->build_header(skb, dev, type, _daddr);
693}
694
695/* Called by the kernel in order to transmit a packet. */
696netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
697 struct net_device *dev)
698{
699 struct arcnet_local *lp = netdev_priv(dev);
700 struct archdr *pkt;
701 struct arc_rfc1201 *soft;
702 struct ArcProto *proto;
703 int txbuf;
704 unsigned long flags;
705 int retval;
706
707 arc_printk(D_DURING, dev,
708 "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
709 lp->hw.status(dev), lp->cur_tx, lp->next_tx, skb->len, skb->protocol);
710
711 pkt = (struct archdr *)skb->data;
712 soft = &pkt->soft.rfc1201;
713 proto = arc_proto_map[soft->proto];
714
715 arc_printk(D_SKB_SIZE, dev, "skb: transmitting %d bytes to %02X\n",
716 skb->len, pkt->hard.dest);
717 if (BUGLVL(D_SKB))
718 arcnet_dump_skb(dev, skb, desc: "tx");
719
720 /* fits in one packet? */
721 if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
722 arc_printk(D_NORMAL, dev, "fixme: packet too large: compensating badly!\n");
723 dev_kfree_skb(skb);
724 return NETDEV_TX_OK; /* don't try again */
725 }
726
727 /* We're busy transmitting a packet... */
728 netif_stop_queue(dev);
729
730 spin_lock_irqsave(&lp->lock, flags);
731 lp->hw.intmask(dev, 0);
732 if (lp->next_tx == -1)
733 txbuf = get_arcbuf(dev);
734 else
735 txbuf = -1;
736
737 if (txbuf != -1) {
738 lp->outgoing.skb = skb;
739 if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
740 !proto->ack_tx) {
741 /* done right away and we don't want to acknowledge
742 * the package later - forget about it now
743 */
744 dev->stats.tx_bytes += skb->len;
745 } else {
746 /* do it the 'split' way */
747 lp->outgoing.proto = proto;
748 lp->outgoing.skb = skb;
749 lp->outgoing.pkt = pkt;
750
751 if (proto->continue_tx &&
752 proto->continue_tx(dev, txbuf)) {
753 arc_printk(D_NORMAL, dev,
754 "bug! continue_tx finished the first time! (proto='%c')\n",
755 proto->suffix);
756 }
757 }
758 retval = NETDEV_TX_OK;
759 lp->next_tx = txbuf;
760 } else {
761 retval = NETDEV_TX_BUSY;
762 }
763
764 arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
765 __FILE__, __LINE__, __func__, lp->hw.status(dev));
766 /* make sure we didn't ignore a TX IRQ while we were in here */
767 lp->hw.intmask(dev, 0);
768
769 arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
770 lp->intmask |= TXFREEflag | EXCNAKflag;
771 lp->hw.intmask(dev, lp->intmask);
772 arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
773 __FILE__, __LINE__, __func__, lp->hw.status(dev));
774
775 arcnet_led_event(dev, ARCNET_LED_EVENT_TX);
776
777 spin_unlock_irqrestore(lock: &lp->lock, flags);
778 return retval; /* no need to try again */
779}
780EXPORT_SYMBOL(arcnet_send_packet);
781
782/* Actually start transmitting a packet that was loaded into a buffer
783 * by prepare_tx. This should _only_ be called by the interrupt handler.
784 */
785static int go_tx(struct net_device *dev)
786{
787 struct arcnet_local *lp = netdev_priv(dev);
788
789 arc_printk(D_DURING, dev, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
790 lp->hw.status(dev), lp->intmask, lp->next_tx, lp->cur_tx);
791
792 if (lp->cur_tx != -1 || lp->next_tx == -1)
793 return 0;
794
795 if (BUGLVL(D_TX))
796 arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
797
798 lp->cur_tx = lp->next_tx;
799 lp->next_tx = -1;
800
801 /* start sending */
802 lp->hw.command(dev, TXcmd | (lp->cur_tx << 3));
803
804 dev->stats.tx_packets++;
805 lp->lasttrans_dest = lp->lastload_dest;
806 lp->lastload_dest = 0;
807 lp->excnak_pending = 0;
808 lp->intmask |= TXFREEflag | EXCNAKflag;
809
810 return 1;
811}
812
813/* Called by the kernel when transmit times out */
814void arcnet_timeout(struct net_device *dev, unsigned int txqueue)
815{
816 unsigned long flags;
817 struct arcnet_local *lp = netdev_priv(dev);
818 int status = lp->hw.status(dev);
819 char *msg;
820
821 spin_lock_irqsave(&lp->lock, flags);
822 if (status & TXFREEflag) { /* transmit _DID_ finish */
823 msg = " - missed IRQ?";
824 } else {
825 msg = "";
826 dev->stats.tx_aborted_errors++;
827 lp->timed_out = 1;
828 lp->hw.command(dev, NOTXcmd | (lp->cur_tx << 3));
829 }
830 dev->stats.tx_errors++;
831
832 /* make sure we didn't miss a TX or a EXC NAK IRQ */
833 lp->hw.intmask(dev, 0);
834 lp->intmask |= TXFREEflag | EXCNAKflag;
835 lp->hw.intmask(dev, lp->intmask);
836
837 spin_unlock_irqrestore(lock: &lp->lock, flags);
838
839 if (time_after(jiffies, lp->last_timeout + 10 * HZ)) {
840 arc_printk(D_EXTRA, dev, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
841 msg, status, lp->intmask, lp->lasttrans_dest);
842 lp->last_timeout = jiffies;
843 }
844
845 if (lp->cur_tx == -1)
846 netif_wake_queue(dev);
847}
848EXPORT_SYMBOL(arcnet_timeout);
849
850/* The typical workload of the driver: Handle the network interface
851 * interrupts. Establish which device needs attention, and call the correct
852 * chipset interrupt handler.
853 */
854irqreturn_t arcnet_interrupt(int irq, void *dev_id)
855{
856 struct net_device *dev = dev_id;
857 struct arcnet_local *lp;
858 int recbuf, status, diagstatus, didsomething, boguscount;
859 unsigned long flags;
860 int retval = IRQ_NONE;
861
862 arc_printk(D_DURING, dev, "\n");
863
864 arc_printk(D_DURING, dev, "in arcnet_interrupt\n");
865
866 lp = netdev_priv(dev);
867 BUG_ON(!lp);
868
869 spin_lock_irqsave(&lp->lock, flags);
870
871 if (lp->reset_in_progress)
872 goto out;
873
874 /* RESET flag was enabled - if device is not running, we must
875 * clear it right away (but nothing else).
876 */
877 if (!netif_running(dev)) {
878 if (lp->hw.status(dev) & RESETflag)
879 lp->hw.command(dev, CFLAGScmd | RESETclear);
880 lp->hw.intmask(dev, 0);
881 spin_unlock_irqrestore(lock: &lp->lock, flags);
882 return retval;
883 }
884
885 arc_printk(D_DURING, dev, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
886 lp->hw.status(dev), lp->intmask);
887
888 boguscount = 5;
889 do {
890 status = lp->hw.status(dev);
891 diagstatus = (status >> 8) & 0xFF;
892
893 arc_printk(D_DEBUG, dev, "%s: %d: %s: status=%x\n",
894 __FILE__, __LINE__, __func__, status);
895 didsomething = 0;
896
897 /* RESET flag was enabled - card is resetting and if RX is
898 * disabled, it's NOT because we just got a packet.
899 *
900 * The card is in an undefined state.
901 * Clear it out and start over.
902 */
903 if (status & RESETflag) {
904 arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
905 status);
906
907 lp->reset_in_progress = 1;
908 netif_stop_queue(dev);
909 netif_carrier_off(dev);
910 schedule_work(work: &lp->reset_work);
911
912 /* get out of the interrupt handler! */
913 goto out;
914 }
915 /* RX is inhibited - we must have received something.
916 * Prepare to receive into the next buffer.
917 *
918 * We don't actually copy the received packet from the card
919 * until after the transmit handler runs (and possibly
920 * launches the next tx); this should improve latency slightly
921 * if we get both types of interrupts at once.
922 */
923 recbuf = -1;
924 if (status & lp->intmask & NORXflag) {
925 recbuf = lp->cur_rx;
926 arc_printk(D_DURING, dev, "Buffer #%d: receive irq (status=%Xh)\n",
927 recbuf, status);
928
929 lp->cur_rx = get_arcbuf(dev);
930 if (lp->cur_rx != -1) {
931 arc_printk(D_DURING, dev, "enabling receive to buffer #%d\n",
932 lp->cur_rx);
933 lp->hw.command(dev, RXcmd | (lp->cur_rx << 3) | RXbcasts);
934 }
935 didsomething++;
936 }
937
938 if ((diagstatus & EXCNAKflag)) {
939 arc_printk(D_DURING, dev, "EXCNAK IRQ (diagstat=%Xh)\n",
940 diagstatus);
941
942 lp->hw.command(dev, NOTXcmd); /* disable transmit */
943 lp->excnak_pending = 1;
944
945 lp->hw.command(dev, EXCNAKclear);
946 lp->intmask &= ~(EXCNAKflag);
947 didsomething++;
948 }
949
950 /* a transmit finished, and we're interested in it. */
951 if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
952 int ackstatus;
953 lp->intmask &= ~(TXFREEflag | EXCNAKflag);
954
955 if (status & TXACKflag)
956 ackstatus = 2;
957 else if (lp->excnak_pending)
958 ackstatus = 1;
959 else
960 ackstatus = 0;
961
962 arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
963 status);
964
965 if (lp->cur_tx != -1 && !lp->timed_out) {
966 if (!(status & TXACKflag)) {
967 if (lp->lasttrans_dest != 0) {
968 arc_printk(D_EXTRA, dev,
969 "transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
970 status,
971 lp->lasttrans_dest);
972 dev->stats.tx_errors++;
973 dev->stats.tx_carrier_errors++;
974 } else {
975 arc_printk(D_DURING, dev,
976 "broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
977 status,
978 lp->lasttrans_dest);
979 }
980 }
981
982 if (lp->outgoing.proto &&
983 lp->outgoing.proto->ack_tx) {
984 lp->outgoing.proto
985 ->ack_tx(dev, ackstatus);
986 }
987 lp->reply_status = ackstatus;
988 queue_work(wq: system_bh_highpri_wq, work: &lp->reply_work);
989 }
990 if (lp->cur_tx != -1)
991 release_arcbuf(dev, bufnum: lp->cur_tx);
992
993 lp->cur_tx = -1;
994 lp->timed_out = 0;
995 didsomething++;
996
997 /* send another packet if there is one */
998 go_tx(dev);
999
1000 /* continue a split packet, if any */
1001 if (lp->outgoing.proto &&
1002 lp->outgoing.proto->continue_tx) {
1003 int txbuf = get_arcbuf(dev);
1004
1005 if (txbuf != -1) {
1006 if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
1007 /* that was the last segment */
1008 dev->stats.tx_bytes += lp->outgoing.skb->len;
1009 if (!lp->outgoing.proto->ack_tx) {
1010 dev_kfree_skb_irq(skb: lp->outgoing.skb);
1011 lp->outgoing.proto = NULL;
1012 }
1013 }
1014 lp->next_tx = txbuf;
1015 }
1016 }
1017 /* inform upper layers of idleness, if necessary */
1018 if (lp->cur_tx == -1)
1019 netif_wake_queue(dev);
1020 }
1021 /* now process the received packet, if any */
1022 if (recbuf != -1) {
1023 if (BUGLVL(D_RX))
1024 arcnet_dump_packet(dev, recbuf, "rx irq", 0);
1025
1026 arcnet_rx(dev, bufnum: recbuf);
1027 release_arcbuf(dev, bufnum: recbuf);
1028
1029 didsomething++;
1030 }
1031 if (status & lp->intmask & RECONflag) {
1032 lp->hw.command(dev, CFLAGScmd | CONFIGclear);
1033 dev->stats.tx_carrier_errors++;
1034
1035 arc_printk(D_RECON, dev, "Network reconfiguration detected (status=%Xh)\n",
1036 status);
1037 if (netif_carrier_ok(dev)) {
1038 netif_carrier_off(dev);
1039 netdev_info(dev, format: "link down\n");
1040 }
1041 mod_timer(timer: &lp->timer, expires: jiffies + msecs_to_jiffies(m: 1000));
1042
1043 arcnet_led_event(dev, ARCNET_LED_EVENT_RECON);
1044 /* MYRECON bit is at bit 7 of diagstatus */
1045 if (diagstatus & 0x80)
1046 arc_printk(D_RECON, dev, "Put out that recon myself\n");
1047
1048 /* is the RECON info empty or old? */
1049 if (!lp->first_recon || !lp->last_recon ||
1050 time_after(jiffies, lp->last_recon + HZ * 10)) {
1051 if (lp->network_down)
1052 arc_printk(D_NORMAL, dev, "reconfiguration detected: cabling restored?\n");
1053 lp->first_recon = lp->last_recon = jiffies;
1054 lp->num_recons = lp->network_down = 0;
1055
1056 arc_printk(D_DURING, dev, "recon: clearing counters.\n");
1057 } else { /* add to current RECON counter */
1058 lp->last_recon = jiffies;
1059 lp->num_recons++;
1060
1061 arc_printk(D_DURING, dev, "recon: counter=%d, time=%lds, net=%d\n",
1062 lp->num_recons,
1063 (lp->last_recon - lp->first_recon) / HZ,
1064 lp->network_down);
1065
1066 /* if network is marked up;
1067 * and first_recon and last_recon are 60+ apart;
1068 * and the average no. of recons counted is
1069 * > RECON_THRESHOLD/min;
1070 * then print a warning message.
1071 */
1072 if (!lp->network_down &&
1073 (lp->last_recon - lp->first_recon) <= HZ * 60 &&
1074 lp->num_recons >= RECON_THRESHOLD) {
1075 lp->network_down = 1;
1076 arc_printk(D_NORMAL, dev, "many reconfigurations detected: cabling problem?\n");
1077 } else if (!lp->network_down &&
1078 lp->last_recon - lp->first_recon > HZ * 60) {
1079 /* reset counters if we've gone for
1080 * over a minute.
1081 */
1082 lp->first_recon = lp->last_recon;
1083 lp->num_recons = 1;
1084 }
1085 }
1086 } else if (lp->network_down &&
1087 time_after(jiffies, lp->last_recon + HZ * 10)) {
1088 if (lp->network_down)
1089 arc_printk(D_NORMAL, dev, "cabling restored?\n");
1090 lp->first_recon = lp->last_recon = 0;
1091 lp->num_recons = lp->network_down = 0;
1092
1093 arc_printk(D_DURING, dev, "not recon: clearing counters anyway.\n");
1094 netif_carrier_on(dev);
1095 }
1096
1097 if (didsomething)
1098 retval |= IRQ_HANDLED;
1099 } while (--boguscount && didsomething);
1100
1101 arc_printk(D_DURING, dev, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
1102 lp->hw.status(dev), boguscount);
1103 arc_printk(D_DURING, dev, "\n");
1104
1105 lp->hw.intmask(dev, 0);
1106 udelay(usec: 1);
1107 lp->hw.intmask(dev, lp->intmask);
1108
1109out:
1110 spin_unlock_irqrestore(lock: &lp->lock, flags);
1111 return retval;
1112}
1113EXPORT_SYMBOL(arcnet_interrupt);
1114
1115/* This is a generic packet receiver that calls arcnet??_rx depending on the
1116 * protocol ID found.
1117 */
1118static void arcnet_rx(struct net_device *dev, int bufnum)
1119{
1120 struct arcnet_local *lp = netdev_priv(dev);
1121 union {
1122 struct archdr pkt;
1123 char buf[512];
1124 } rxdata;
1125 struct arc_rfc1201 *soft;
1126 int length, ofs;
1127
1128 soft = &rxdata.pkt.soft.rfc1201;
1129
1130 lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);
1131 if (rxdata.pkt.hard.offset[0]) {
1132 ofs = rxdata.pkt.hard.offset[0];
1133 length = 256 - ofs;
1134 } else {
1135 ofs = rxdata.pkt.hard.offset[1];
1136 length = 512 - ofs;
1137 }
1138
1139 /* get the full header, if possible */
1140 if (sizeof(rxdata.pkt.soft) <= length) {
1141 lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));
1142 } else {
1143 memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));
1144 lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1145 }
1146
1147 arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
1148 bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);
1149
1150 dev->stats.rx_packets++;
1151 dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1152
1153 /* call the right receiver for the protocol */
1154 if (arc_proto_map[soft->proto]->is_ip) {
1155 if (BUGLVL(D_PROTO)) {
1156 struct ArcProto
1157 *oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],
1158 *newp = arc_proto_map[soft->proto];
1159
1160 if (oldp != newp) {
1161 arc_printk(D_PROTO, dev,
1162 "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
1163 soft->proto, rxdata.pkt.hard.source,
1164 newp->suffix, oldp->suffix);
1165 }
1166 }
1167
1168 /* broadcasts will always be done with the last-used encap. */
1169 lp->default_proto[0] = soft->proto;
1170
1171 /* in striking contrast, the following isn't a hack. */
1172 lp->default_proto[rxdata.pkt.hard.source] = soft->proto;
1173 }
1174 /* call the protocol-specific receiver. */
1175 arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);
1176}
1177
1178static void null_rx(struct net_device *dev, int bufnum,
1179 struct archdr *pkthdr, int length)
1180{
1181 arc_printk(D_PROTO, dev,
1182 "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1183 pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1184}
1185
1186static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1187 unsigned short type, uint8_t daddr)
1188{
1189 struct arcnet_local *lp = netdev_priv(dev);
1190
1191 arc_printk(D_PROTO, dev,
1192 "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1193 lp->default_proto[daddr]);
1194
1195 /* always fails */
1196 return 0;
1197}
1198
1199/* the "do nothing" prepare_tx function warns that there's nothing to do. */
1200static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1201 int length, int bufnum)
1202{
1203 struct arcnet_local *lp = netdev_priv(dev);
1204 struct arc_hardware newpkt;
1205
1206 arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
1207
1208 /* send a packet to myself -- will never get received, of course */
1209 newpkt.source = newpkt.dest = dev->dev_addr[0];
1210
1211 /* only one byte of actual data (and it's random) */
1212 newpkt.offset[0] = 0xFF;
1213
1214 lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1215
1216 return 1; /* done */
1217}
1218

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