Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * PCBIT-D low-layer interface | |
3 | * | |
4 | * Copyright (C) 1996 Universidade de Lisboa | |
5 | * | |
6 | * Written by Pedro Roque Marques (roque@di.fc.ul.pt) | |
7 | * | |
8 | * This software may be used and distributed according to the terms of | |
9 | * the GNU General Public License, incorporated herein by reference. | |
10 | */ | |
11 | ||
12 | /* | |
13 | * 19991203 - Fernando Carvalho - takion@superbofh.org | |
14 | * Hacked to compile with egcs and run with current version of isdn modules | |
15 | */ | |
16 | ||
17 | /* | |
18 | * Based on documentation provided by Inesc: | |
19 | * - "Interface com bus do PC para o PCBIT e PCBIT-D", Inesc, Jan 93 | |
20 | */ | |
21 | ||
22 | /* | |
23 | * TODO: better handling of errors | |
24 | * re-write/remove debug printks | |
25 | */ | |
26 | ||
27 | #include <linux/sched.h> | |
28 | #include <linux/string.h> | |
29 | #include <linux/kernel.h> | |
30 | #include <linux/types.h> | |
31 | #include <linux/slab.h> | |
32 | #include <linux/interrupt.h> | |
33 | #include <linux/workqueue.h> | |
34 | #include <linux/mm.h> | |
35 | #include <linux/skbuff.h> | |
36 | ||
37 | #include <linux/isdnif.h> | |
38 | ||
39 | #include <asm/system.h> | |
40 | #include <asm/io.h> | |
41 | ||
42 | ||
43 | #include "pcbit.h" | |
44 | #include "layer2.h" | |
45 | #include "edss1.h" | |
46 | ||
47 | #undef DEBUG_FRAG | |
48 | ||
49 | ||
50 | ||
51 | /* | |
52 | * task queue struct | |
53 | */ | |
54 | ||
55 | ||
56 | ||
57 | /* | |
58 | * Layer 3 packet demultiplexer | |
59 | * drv.c | |
60 | */ | |
61 | ||
62 | extern void pcbit_l3_receive(struct pcbit_dev *dev, ulong msg, | |
63 | struct sk_buff *skb, | |
64 | ushort hdr_len, ushort refnum); | |
65 | ||
66 | /* | |
67 | * Prototypes | |
68 | */ | |
69 | ||
70 | void pcbit_deliver(void *data); | |
71 | static void pcbit_transmit(struct pcbit_dev *dev); | |
72 | ||
73 | static void pcbit_recv_ack(struct pcbit_dev *dev, unsigned char ack); | |
74 | ||
75 | static void pcbit_l2_error(struct pcbit_dev *dev); | |
76 | static void pcbit_l2_active_conf(struct pcbit_dev *dev, u_char info); | |
77 | static void pcbit_l2_err_recover(unsigned long data); | |
78 | ||
79 | static void pcbit_firmware_bug(struct pcbit_dev *dev); | |
80 | ||
81 | static __inline__ void | |
82 | pcbit_sched_delivery(struct pcbit_dev *dev) | |
83 | { | |
84 | schedule_work(&dev->qdelivery); | |
85 | } | |
86 | ||
87 | ||
88 | /* | |
89 | * Called from layer3 | |
90 | */ | |
91 | ||
92 | int | |
93 | pcbit_l2_write(struct pcbit_dev *dev, ulong msg, ushort refnum, | |
94 | struct sk_buff *skb, unsigned short hdr_len) | |
95 | { | |
96 | struct frame_buf *frame, | |
97 | *ptr; | |
98 | unsigned long flags; | |
99 | ||
100 | if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) { | |
101 | dev_kfree_skb(skb); | |
102 | return -1; | |
103 | } | |
104 | if ((frame = (struct frame_buf *) kmalloc(sizeof(struct frame_buf), | |
105 | GFP_ATOMIC)) == NULL) { | |
106 | printk(KERN_WARNING "pcbit_2_write: kmalloc failed\n"); | |
107 | dev_kfree_skb(skb); | |
108 | return -1; | |
109 | } | |
110 | frame->msg = msg; | |
111 | frame->refnum = refnum; | |
112 | frame->copied = 0; | |
113 | frame->hdr_len = hdr_len; | |
114 | ||
115 | if (skb) | |
116 | frame->dt_len = skb->len - hdr_len; | |
117 | else | |
118 | frame->dt_len = 0; | |
119 | ||
120 | frame->skb = skb; | |
121 | ||
122 | frame->next = NULL; | |
123 | ||
124 | spin_lock_irqsave(&dev->lock, flags); | |
125 | ||
126 | if (dev->write_queue == NULL) { | |
127 | dev->write_queue = frame; | |
128 | spin_unlock_irqrestore(&dev->lock, flags); | |
129 | pcbit_transmit(dev); | |
130 | } else { | |
131 | for (ptr = dev->write_queue; ptr->next; ptr = ptr->next); | |
132 | ptr->next = frame; | |
133 | ||
134 | spin_unlock_irqrestore(&dev->lock, flags); | |
135 | } | |
136 | return 0; | |
137 | } | |
138 | ||
139 | static __inline__ void | |
140 | pcbit_tx_update(struct pcbit_dev *dev, ushort len) | |
141 | { | |
142 | u_char info; | |
143 | ||
144 | dev->send_seq = (dev->send_seq + 1) % 8; | |
145 | ||
146 | dev->fsize[dev->send_seq] = len; | |
147 | info = 0; | |
148 | info |= dev->rcv_seq << 3; | |
149 | info |= dev->send_seq; | |
150 | ||
151 | writeb(info, dev->sh_mem + BANK4); | |
152 | ||
153 | } | |
154 | ||
155 | /* | |
156 | * called by interrupt service routine or by write_2 | |
157 | */ | |
158 | ||
159 | static void | |
160 | pcbit_transmit(struct pcbit_dev *dev) | |
161 | { | |
162 | struct frame_buf *frame = NULL; | |
163 | unsigned char unacked; | |
164 | int flen; /* fragment frame length including all headers */ | |
165 | int free; | |
166 | int count, | |
167 | cp_len; | |
168 | unsigned long flags; | |
169 | unsigned short tt; | |
170 | ||
171 | if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) | |
172 | return; | |
173 | ||
174 | unacked = (dev->send_seq + (8 - dev->unack_seq)) & 0x07; | |
175 | ||
176 | spin_lock_irqsave(&dev->lock, flags); | |
177 | ||
178 | if (dev->free > 16 && dev->write_queue && unacked < 7) { | |
179 | ||
180 | if (!dev->w_busy) | |
181 | dev->w_busy = 1; | |
182 | else { | |
183 | spin_unlock_irqrestore(&dev->lock, flags); | |
184 | return; | |
185 | } | |
186 | ||
187 | ||
188 | frame = dev->write_queue; | |
189 | free = dev->free; | |
190 | ||
191 | spin_unlock_irqrestore(&dev->lock, flags); | |
192 | ||
193 | if (frame->copied == 0) { | |
194 | ||
195 | /* Type 0 frame */ | |
196 | ||
197 | ulong msg; | |
198 | ||
199 | if (frame->skb) | |
200 | flen = FRAME_HDR_LEN + PREHDR_LEN + frame->skb->len; | |
201 | else | |
202 | flen = FRAME_HDR_LEN + PREHDR_LEN; | |
203 | ||
204 | if (flen > free) | |
205 | flen = free; | |
206 | ||
207 | msg = frame->msg; | |
208 | ||
209 | /* | |
210 | * Board level 2 header | |
211 | */ | |
212 | ||
213 | pcbit_writew(dev, flen - FRAME_HDR_LEN); | |
214 | ||
215 | pcbit_writeb(dev, GET_MSG_CPU(msg)); | |
216 | ||
217 | pcbit_writeb(dev, GET_MSG_PROC(msg)); | |
218 | ||
219 | /* TH */ | |
220 | pcbit_writew(dev, frame->hdr_len + PREHDR_LEN); | |
221 | ||
222 | /* TD */ | |
223 | pcbit_writew(dev, frame->dt_len); | |
224 | ||
225 | ||
226 | /* | |
227 | * Board level 3 fixed-header | |
228 | */ | |
229 | ||
230 | /* LEN = TH */ | |
231 | pcbit_writew(dev, frame->hdr_len + PREHDR_LEN); | |
232 | ||
233 | /* XX */ | |
234 | pcbit_writew(dev, 0); | |
235 | ||
236 | /* C + S */ | |
237 | pcbit_writeb(dev, GET_MSG_CMD(msg)); | |
238 | pcbit_writeb(dev, GET_MSG_SCMD(msg)); | |
239 | ||
240 | /* NUM */ | |
241 | pcbit_writew(dev, frame->refnum); | |
242 | ||
243 | count = FRAME_HDR_LEN + PREHDR_LEN; | |
244 | } else { | |
245 | /* Type 1 frame */ | |
246 | ||
247 | flen = 2 + (frame->skb->len - frame->copied); | |
248 | ||
249 | if (flen > free) | |
250 | flen = free; | |
251 | ||
252 | /* TT */ | |
253 | tt = ((ushort) (flen - 2)) | 0x8000U; /* Type 1 */ | |
254 | pcbit_writew(dev, tt); | |
255 | ||
256 | count = 2; | |
257 | } | |
258 | ||
259 | if (frame->skb) { | |
260 | cp_len = frame->skb->len - frame->copied; | |
261 | if (cp_len > flen - count) | |
262 | cp_len = flen - count; | |
263 | ||
264 | memcpy_topcbit(dev, frame->skb->data + frame->copied, | |
265 | cp_len); | |
266 | frame->copied += cp_len; | |
267 | } | |
268 | /* bookkeeping */ | |
269 | dev->free -= flen; | |
270 | pcbit_tx_update(dev, flen); | |
271 | ||
272 | spin_lock_irqsave(&dev->lock, flags); | |
273 | ||
274 | if (frame->skb == NULL || frame->copied == frame->skb->len) { | |
275 | ||
276 | dev->write_queue = frame->next; | |
277 | ||
278 | if (frame->skb != NULL) { | |
279 | /* free frame */ | |
280 | dev_kfree_skb(frame->skb); | |
281 | } | |
282 | kfree(frame); | |
283 | } | |
284 | dev->w_busy = 0; | |
285 | spin_unlock_irqrestore(&dev->lock, flags); | |
286 | } else { | |
287 | spin_unlock_irqrestore(&dev->lock, flags); | |
288 | #ifdef DEBUG | |
289 | printk(KERN_DEBUG "unacked %d free %d write_queue %s\n", | |
290 | unacked, dev->free, dev->write_queue ? "not empty" : | |
291 | "empty"); | |
292 | #endif | |
293 | } | |
294 | } | |
295 | ||
296 | ||
297 | /* | |
298 | * deliver a queued frame to the upper layer | |
299 | */ | |
300 | ||
301 | void | |
302 | pcbit_deliver(void *data) | |
303 | { | |
304 | struct frame_buf *frame; | |
305 | unsigned long flags, msg; | |
306 | struct pcbit_dev *dev = (struct pcbit_dev *) data; | |
307 | ||
308 | spin_lock_irqsave(&dev->lock, flags); | |
309 | ||
310 | while ((frame = dev->read_queue)) { | |
311 | dev->read_queue = frame->next; | |
312 | spin_unlock_irqrestore(&dev->lock, flags); | |
313 | ||
314 | SET_MSG_CPU(msg, 0); | |
315 | SET_MSG_PROC(msg, 0); | |
316 | SET_MSG_CMD(msg, frame->skb->data[2]); | |
317 | SET_MSG_SCMD(msg, frame->skb->data[3]); | |
318 | ||
319 | frame->refnum = *((ushort *) frame->skb->data + 4); | |
320 | frame->msg = *((ulong *) & msg); | |
321 | ||
322 | skb_pull(frame->skb, 6); | |
323 | ||
324 | pcbit_l3_receive(dev, frame->msg, frame->skb, frame->hdr_len, | |
325 | frame->refnum); | |
326 | ||
327 | kfree(frame); | |
328 | ||
329 | spin_lock_irqsave(&dev->lock, flags); | |
330 | } | |
331 | ||
332 | spin_unlock_irqrestore(&dev->lock, flags); | |
333 | } | |
334 | ||
335 | /* | |
336 | * Reads BANK 2 & Reassembles | |
337 | */ | |
338 | ||
339 | static void | |
340 | pcbit_receive(struct pcbit_dev *dev) | |
341 | { | |
342 | unsigned short tt; | |
343 | u_char cpu, | |
344 | proc; | |
345 | struct frame_buf *frame = NULL; | |
346 | unsigned long flags; | |
347 | u_char type1; | |
348 | ||
349 | if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) | |
350 | return; | |
351 | ||
352 | tt = pcbit_readw(dev); | |
353 | ||
354 | if ((tt & 0x7fffU) > 511) { | |
355 | printk(KERN_INFO "pcbit: invalid frame length -> TT=%04x\n", | |
356 | tt); | |
357 | pcbit_l2_error(dev); | |
358 | return; | |
359 | } | |
360 | if (!(tt & 0x8000U)) { /* Type 0 */ | |
361 | type1 = 0; | |
362 | ||
363 | if (dev->read_frame) { | |
364 | printk(KERN_DEBUG "pcbit_receive: Type 0 frame and read_frame != NULL\n"); | |
365 | /* discard previous queued frame */ | |
366 | if (dev->read_frame->skb) | |
367 | kfree_skb(dev->read_frame->skb); | |
368 | kfree(dev->read_frame); | |
369 | dev->read_frame = NULL; | |
370 | } | |
371 | frame = kmalloc(sizeof(struct frame_buf), GFP_ATOMIC); | |
372 | ||
373 | if (frame == NULL) { | |
374 | printk(KERN_WARNING "kmalloc failed\n"); | |
375 | return; | |
376 | } | |
377 | memset(frame, 0, sizeof(struct frame_buf)); | |
378 | ||
379 | cpu = pcbit_readb(dev); | |
380 | proc = pcbit_readb(dev); | |
381 | ||
382 | ||
383 | if (cpu != 0x06 && cpu != 0x02) { | |
384 | printk(KERN_DEBUG "pcbit: invalid cpu value\n"); | |
385 | kfree(frame); | |
386 | pcbit_l2_error(dev); | |
387 | return; | |
388 | } | |
389 | /* | |
390 | * we discard cpu & proc on receiving | |
391 | * but we read it to update the pointer | |
392 | */ | |
393 | ||
394 | frame->hdr_len = pcbit_readw(dev); | |
395 | frame->dt_len = pcbit_readw(dev); | |
396 | ||
397 | /* | |
398 | * 0 sized packet | |
399 | * I don't know if they are an error or not... | |
400 | * But they are very frequent | |
401 | * Not documented | |
402 | */ | |
403 | ||
404 | if (frame->hdr_len == 0) { | |
405 | kfree(frame); | |
406 | #ifdef DEBUG | |
407 | printk(KERN_DEBUG "0 sized frame\n"); | |
408 | #endif | |
409 | pcbit_firmware_bug(dev); | |
410 | return; | |
411 | } | |
412 | /* sanity check the length values */ | |
413 | if (frame->hdr_len > 1024 || frame->dt_len > 2048) { | |
414 | #ifdef DEBUG | |
415 | printk(KERN_DEBUG "length problem: "); | |
416 | printk(KERN_DEBUG "TH=%04x TD=%04x\n", | |
417 | frame->hdr_len, | |
418 | frame->dt_len); | |
419 | #endif | |
420 | pcbit_l2_error(dev); | |
421 | kfree(frame); | |
422 | return; | |
423 | } | |
424 | /* minimum frame read */ | |
425 | ||
426 | frame->skb = dev_alloc_skb(frame->hdr_len + frame->dt_len + | |
427 | ((frame->hdr_len + 15) & ~15)); | |
428 | ||
429 | if (!frame->skb) { | |
430 | printk(KERN_DEBUG "pcbit_receive: out of memory\n"); | |
431 | kfree(frame); | |
432 | return; | |
433 | } | |
434 | /* 16 byte alignment for IP */ | |
435 | if (frame->dt_len) | |
436 | skb_reserve(frame->skb, (frame->hdr_len + 15) & ~15); | |
437 | ||
438 | } else { | |
439 | /* Type 1 */ | |
440 | type1 = 1; | |
441 | tt &= 0x7fffU; | |
442 | ||
443 | if (!(frame = dev->read_frame)) { | |
444 | printk("Type 1 frame and no frame queued\n"); | |
445 | /* usually after an error: toss frame */ | |
446 | dev->readptr += tt; | |
447 | if (dev->readptr > dev->sh_mem + BANK2 + BANKLEN) | |
448 | dev->readptr -= BANKLEN; | |
449 | return; | |
450 | ||
451 | } | |
452 | } | |
453 | ||
454 | memcpy_frompcbit(dev, skb_put(frame->skb, tt), tt); | |
455 | ||
456 | frame->copied += tt; | |
457 | spin_lock_irqsave(&dev->lock, flags); | |
458 | if (frame->copied == frame->hdr_len + frame->dt_len) { | |
459 | ||
460 | if (type1) { | |
461 | dev->read_frame = NULL; | |
462 | } | |
463 | if (dev->read_queue) { | |
464 | struct frame_buf *ptr; | |
465 | for (ptr = dev->read_queue; ptr->next; ptr = ptr->next); | |
466 | ptr->next = frame; | |
467 | } else | |
468 | dev->read_queue = frame; | |
469 | ||
470 | } else { | |
471 | dev->read_frame = frame; | |
472 | } | |
473 | spin_unlock_irqrestore(&dev->lock, flags); | |
474 | } | |
475 | ||
476 | /* | |
477 | * The board sends 0 sized frames | |
478 | * They are TDATA_CONFs that get messed up somehow | |
479 | * gotta send a fake acknowledgment to the upper layer somehow | |
480 | */ | |
481 | ||
482 | static __inline__ void | |
483 | pcbit_fake_conf(struct pcbit_dev *dev, struct pcbit_chan *chan) | |
484 | { | |
485 | isdn_ctrl ictl; | |
486 | ||
487 | if (chan->queued) { | |
488 | chan->queued--; | |
489 | ||
490 | ictl.driver = dev->id; | |
491 | ictl.command = ISDN_STAT_BSENT; | |
492 | ictl.arg = chan->id; | |
493 | dev->dev_if->statcallb(&ictl); | |
494 | } | |
495 | } | |
496 | ||
497 | static void | |
498 | pcbit_firmware_bug(struct pcbit_dev *dev) | |
499 | { | |
500 | struct pcbit_chan *chan; | |
501 | ||
502 | chan = dev->b1; | |
503 | ||
504 | if (chan->fsm_state == ST_ACTIVE) { | |
505 | pcbit_fake_conf(dev, chan); | |
506 | } | |
507 | chan = dev->b2; | |
508 | ||
509 | if (chan->fsm_state == ST_ACTIVE) { | |
510 | pcbit_fake_conf(dev, chan); | |
511 | } | |
512 | } | |
513 | ||
514 | irqreturn_t | |
7d12e780 | 515 | pcbit_irq_handler(int interrupt, void *devptr) |
1da177e4 LT |
516 | { |
517 | struct pcbit_dev *dev; | |
518 | u_char info, | |
519 | ack_seq, | |
520 | read_seq; | |
521 | ||
522 | dev = (struct pcbit_dev *) devptr; | |
523 | ||
524 | if (!dev) { | |
525 | printk(KERN_WARNING "pcbit_irq_handler: wrong device\n"); | |
526 | return IRQ_NONE; | |
527 | } | |
528 | if (dev->interrupt) { | |
529 | printk(KERN_DEBUG "pcbit: reentering interrupt hander\n"); | |
530 | return IRQ_HANDLED; | |
531 | } | |
532 | dev->interrupt = 1; | |
533 | ||
534 | info = readb(dev->sh_mem + BANK3); | |
535 | ||
536 | if (dev->l2_state == L2_STARTING || dev->l2_state == L2_ERROR) { | |
537 | pcbit_l2_active_conf(dev, info); | |
538 | dev->interrupt = 0; | |
539 | return IRQ_HANDLED; | |
540 | } | |
541 | if (info & 0x40U) { /* E bit set */ | |
542 | #ifdef DEBUG | |
543 | printk(KERN_DEBUG "pcbit_irq_handler: E bit on\n"); | |
544 | #endif | |
545 | pcbit_l2_error(dev); | |
546 | dev->interrupt = 0; | |
547 | return IRQ_HANDLED; | |
548 | } | |
549 | if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) { | |
550 | dev->interrupt = 0; | |
551 | return IRQ_HANDLED; | |
552 | } | |
553 | ack_seq = (info >> 3) & 0x07U; | |
554 | read_seq = (info & 0x07U); | |
555 | ||
556 | dev->interrupt = 0; | |
557 | ||
558 | if (read_seq != dev->rcv_seq) { | |
559 | while (read_seq != dev->rcv_seq) { | |
560 | pcbit_receive(dev); | |
561 | dev->rcv_seq = (dev->rcv_seq + 1) % 8; | |
562 | } | |
563 | pcbit_sched_delivery(dev); | |
564 | } | |
565 | if (ack_seq != dev->unack_seq) { | |
566 | pcbit_recv_ack(dev, ack_seq); | |
567 | } | |
568 | info = dev->rcv_seq << 3; | |
569 | info |= dev->send_seq; | |
570 | ||
571 | writeb(info, dev->sh_mem + BANK4); | |
572 | return IRQ_HANDLED; | |
573 | } | |
574 | ||
575 | ||
576 | static void | |
577 | pcbit_l2_active_conf(struct pcbit_dev *dev, u_char info) | |
578 | { | |
579 | u_char state; | |
580 | ||
581 | state = dev->l2_state; | |
582 | ||
583 | #ifdef DEBUG | |
584 | printk(KERN_DEBUG "layer2_active_confirm\n"); | |
585 | #endif | |
586 | ||
587 | ||
588 | if (info & 0x80U) { | |
589 | dev->rcv_seq = info & 0x07U; | |
590 | dev->l2_state = L2_RUNNING; | |
591 | } else | |
592 | dev->l2_state = L2_DOWN; | |
593 | ||
594 | if (state == L2_STARTING) | |
595 | wake_up_interruptible(&dev->set_running_wq); | |
596 | ||
597 | if (state == L2_ERROR && dev->l2_state == L2_RUNNING) { | |
598 | pcbit_transmit(dev); | |
599 | } | |
600 | } | |
601 | ||
602 | static void | |
603 | pcbit_l2_err_recover(unsigned long data) | |
604 | { | |
605 | ||
606 | struct pcbit_dev *dev; | |
607 | struct frame_buf *frame; | |
608 | ||
609 | dev = (struct pcbit_dev *) data; | |
610 | ||
611 | del_timer(&dev->error_recover_timer); | |
612 | if (dev->w_busy || dev->r_busy) { | |
613 | init_timer(&dev->error_recover_timer); | |
614 | dev->error_recover_timer.expires = jiffies + ERRTIME; | |
615 | add_timer(&dev->error_recover_timer); | |
616 | return; | |
617 | } | |
618 | dev->w_busy = dev->r_busy = 1; | |
619 | ||
620 | if (dev->read_frame) { | |
621 | if (dev->read_frame->skb) | |
622 | kfree_skb(dev->read_frame->skb); | |
623 | kfree(dev->read_frame); | |
624 | dev->read_frame = NULL; | |
625 | } | |
626 | if (dev->write_queue) { | |
627 | frame = dev->write_queue; | |
628 | #ifdef FREE_ON_ERROR | |
629 | dev->write_queue = dev->write_queue->next; | |
630 | ||
631 | if (frame->skb) { | |
632 | dev_kfree_skb(frame->skb); | |
633 | } | |
634 | kfree(frame); | |
635 | #else | |
636 | frame->copied = 0; | |
637 | #endif | |
638 | } | |
639 | dev->rcv_seq = dev->send_seq = dev->unack_seq = 0; | |
640 | dev->free = 511; | |
641 | dev->l2_state = L2_ERROR; | |
642 | ||
643 | /* this is an hack... */ | |
644 | pcbit_firmware_bug(dev); | |
645 | ||
646 | dev->writeptr = dev->sh_mem; | |
647 | dev->readptr = dev->sh_mem + BANK2; | |
648 | ||
649 | writeb((0x80U | ((dev->rcv_seq & 0x07) << 3) | (dev->send_seq & 0x07)), | |
650 | dev->sh_mem + BANK4); | |
651 | dev->w_busy = dev->r_busy = 0; | |
652 | ||
653 | } | |
654 | ||
655 | static void | |
656 | pcbit_l2_error(struct pcbit_dev *dev) | |
657 | { | |
658 | if (dev->l2_state == L2_RUNNING) { | |
659 | ||
660 | printk(KERN_INFO "pcbit: layer 2 error\n"); | |
661 | ||
662 | #ifdef DEBUG | |
663 | log_state(dev); | |
664 | #endif | |
665 | ||
666 | dev->l2_state = L2_DOWN; | |
667 | ||
668 | init_timer(&dev->error_recover_timer); | |
669 | dev->error_recover_timer.function = &pcbit_l2_err_recover; | |
670 | dev->error_recover_timer.data = (ulong) dev; | |
671 | dev->error_recover_timer.expires = jiffies + ERRTIME; | |
672 | add_timer(&dev->error_recover_timer); | |
673 | } | |
674 | } | |
675 | ||
676 | /* | |
677 | * Description: | |
678 | * if board acks frames | |
679 | * update dev->free | |
680 | * call pcbit_transmit to write possible queued frames | |
681 | */ | |
682 | ||
683 | static void | |
684 | pcbit_recv_ack(struct pcbit_dev *dev, unsigned char ack) | |
685 | { | |
686 | int i, | |
687 | count; | |
688 | int unacked; | |
689 | ||
690 | unacked = (dev->send_seq + (8 - dev->unack_seq)) & 0x07; | |
691 | ||
692 | /* dev->unack_seq < ack <= dev->send_seq; */ | |
693 | ||
694 | if (unacked) { | |
695 | ||
696 | if (dev->send_seq > dev->unack_seq) { | |
697 | if (ack <= dev->unack_seq || ack > dev->send_seq) { | |
698 | printk(KERN_DEBUG | |
699 | "layer 2 ack unacceptable - dev %d", | |
700 | dev->id); | |
701 | ||
702 | pcbit_l2_error(dev); | |
703 | } else if (ack > dev->send_seq && ack <= dev->unack_seq) { | |
704 | printk(KERN_DEBUG | |
705 | "layer 2 ack unacceptable - dev %d", | |
706 | dev->id); | |
707 | pcbit_l2_error(dev); | |
708 | } | |
709 | } | |
710 | /* ack is acceptable */ | |
711 | ||
712 | ||
713 | i = dev->unack_seq; | |
714 | ||
715 | do { | |
716 | dev->unack_seq = i = (i + 1) % 8; | |
717 | dev->free += dev->fsize[i]; | |
718 | } while (i != ack); | |
719 | ||
720 | count = 0; | |
721 | while (count < 7 && dev->write_queue) { | |
722 | u8 lsend_seq = dev->send_seq; | |
723 | ||
724 | pcbit_transmit(dev); | |
725 | ||
726 | if (dev->send_seq == lsend_seq) | |
727 | break; | |
728 | count++; | |
729 | } | |
730 | } else | |
731 | printk(KERN_DEBUG "recv_ack: unacked = 0\n"); | |
732 | } |