1 /*
2  * IEEE 1394 for Linux
3  *
4  * Transaction support.
5  *
6  * Copyright (C) 1999 Andreas E. Bombe
7  *
8  * This code is licensed under the GPL.  See the file COPYING in the root
9  * directory of the kernel sources for details.
10  */
11 
12 #include <linux/sched.h>
13 #include <linux/bitops.h>
14 #include <asm/errno.h>
15 #include <linux/interrupt.h>
16 
17 #include "ieee1394.h"
18 #include "ieee1394_types.h"
19 #include "hosts.h"
20 #include "ieee1394_core.h"
21 #include "highlevel.h"
22 #include "nodemgr.h"
23 
24 
25 #define PREP_ASYNC_HEAD_ADDRESS(tc) \
26         packet->tcode = tc; \
27         packet->header[0] = (packet->node_id << 16) | (packet->tlabel << 10) \
28                 | (1 << 8) | (tc << 4); \
29         packet->header[1] = (packet->host->node_id << 16) | (addr >> 32); \
30         packet->header[2] = addr & 0xffffffff
31 
32 
fill_async_readquad(struct hpsb_packet * packet,u64 addr)33 static void fill_async_readquad(struct hpsb_packet *packet, u64 addr)
34 {
35         PREP_ASYNC_HEAD_ADDRESS(TCODE_READQ);
36         packet->header_size = 12;
37         packet->data_size = 0;
38         packet->expect_response = 1;
39 }
40 
fill_async_readblock(struct hpsb_packet * packet,u64 addr,int length)41 static void fill_async_readblock(struct hpsb_packet *packet, u64 addr, int length)
42 {
43         PREP_ASYNC_HEAD_ADDRESS(TCODE_READB);
44         packet->header[3] = length << 16;
45         packet->header_size = 16;
46         packet->data_size = 0;
47         packet->expect_response = 1;
48 }
49 
fill_async_writequad(struct hpsb_packet * packet,u64 addr,quadlet_t data)50 static void fill_async_writequad(struct hpsb_packet *packet, u64 addr, quadlet_t data)
51 {
52         PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEQ);
53         packet->header[3] = data;
54         packet->header_size = 16;
55         packet->data_size = 0;
56         packet->expect_response = 1;
57 }
58 
fill_async_writeblock(struct hpsb_packet * packet,u64 addr,int length)59 static void fill_async_writeblock(struct hpsb_packet *packet, u64 addr, int length)
60 {
61         PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEB);
62         packet->header[3] = length << 16;
63         packet->header_size = 16;
64         packet->expect_response = 1;
65         packet->data_size = length + (length % 4 ? 4 - (length % 4) : 0);
66 }
67 
fill_async_lock(struct hpsb_packet * packet,u64 addr,int extcode,int length)68 static void fill_async_lock(struct hpsb_packet *packet, u64 addr, int extcode,
69                      int length)
70 {
71         PREP_ASYNC_HEAD_ADDRESS(TCODE_LOCK_REQUEST);
72         packet->header[3] = (length << 16) | extcode;
73         packet->header_size = 16;
74         packet->data_size = length;
75         packet->expect_response = 1;
76 }
77 
fill_iso_packet(struct hpsb_packet * packet,int length,int channel,int tag,int sync)78 static void fill_iso_packet(struct hpsb_packet *packet, int length, int channel,
79                      int tag, int sync)
80 {
81         packet->header[0] = (length << 16) | (tag << 14) | (channel << 8)
82                 | (TCODE_ISO_DATA << 4) | sync;
83 
84         packet->header_size = 4;
85         packet->data_size = length;
86         packet->type = hpsb_iso;
87         packet->tcode = TCODE_ISO_DATA;
88 }
89 
fill_phy_packet(struct hpsb_packet * packet,quadlet_t data)90 static void fill_phy_packet(struct hpsb_packet *packet, quadlet_t data)
91 {
92         packet->header[0] = data;
93         packet->header[1] = ~data;
94         packet->header_size = 8;
95         packet->data_size = 0;
96         packet->expect_response = 0;
97         packet->type = hpsb_raw;             /* No CRC added */
98         packet->speed_code = IEEE1394_SPEED_100; /* Force speed to be 100Mbps */
99 }
100 
fill_async_stream_packet(struct hpsb_packet * packet,int length,int channel,int tag,int sync)101 static void fill_async_stream_packet(struct hpsb_packet *packet, int length,
102 				     int channel, int tag, int sync)
103 {
104 	packet->header[0] = (length << 16) | (tag << 14) | (channel << 8)
105 	                  | (TCODE_STREAM_DATA << 4) | sync;
106 
107 	packet->header_size = 4;
108 	packet->data_size = length;
109 	packet->type = hpsb_async;
110 	packet->tcode = TCODE_ISO_DATA;
111 }
112 
113 /**
114  * hpsb_get_tlabel - allocate a transaction label
115  * @packet: the packet who's tlabel/tpool we set
116  *
117  * Every asynchronous transaction on the 1394 bus needs a transaction
118  * label to match the response to the request.  This label has to be
119  * different from any other transaction label in an outstanding request to
120  * the same node to make matching possible without ambiguity.
121  *
122  * There are 64 different tlabels, so an allocated tlabel has to be freed
123  * with hpsb_free_tlabel() after the transaction is complete (unless it's
124  * reused again for the same target node).
125  *
126  * Return value: Zero on success, otherwise non-zero. A non-zero return
127  * generally means there are no available tlabels. If this is called out
128  * of interrupt or atomic context, then it will sleep until can return a
129  * tlabel.
130  */
hpsb_get_tlabel(struct hpsb_packet * packet)131 int hpsb_get_tlabel(struct hpsb_packet *packet)
132 {
133 	unsigned long flags;
134 	struct hpsb_tlabel_pool *tp;
135 
136 	tp = &packet->host->tpool[packet->node_id & NODE_MASK];
137 
138 	if (in_interrupt()) {
139 		if (down_trylock(&tp->count))
140 			return 1;
141 	} else {
142 		down(&tp->count);
143 	}
144 
145 	spin_lock_irqsave(&tp->lock, flags);
146 
147 	packet->tlabel = find_next_zero_bit(tp->pool, 64, tp->next);
148 	if (packet->tlabel > 63)
149 		packet->tlabel = find_first_zero_bit(tp->pool, 64);
150 	tp->next = (packet->tlabel + 1) % 64;
151 	/* Should _never_ happen */
152 	BUG_ON(test_and_set_bit(packet->tlabel, tp->pool));
153 	tp->allocations++;
154 	spin_unlock_irqrestore(&tp->lock, flags);
155 
156 	return 0;
157 }
158 
159 /**
160  * hpsb_free_tlabel - free an allocated transaction label
161  * @packet: packet whos tlabel/tpool needs to be cleared
162  *
163  * Frees the transaction label allocated with hpsb_get_tlabel().  The
164  * tlabel has to be freed after the transaction is complete (i.e. response
165  * was received for a split transaction or packet was sent for a unified
166  * transaction).
167  *
168  * A tlabel must not be freed twice.
169  */
hpsb_free_tlabel(struct hpsb_packet * packet)170 void hpsb_free_tlabel(struct hpsb_packet *packet)
171 {
172         unsigned long flags;
173 	struct hpsb_tlabel_pool *tp;
174 
175 	tp = &packet->host->tpool[packet->node_id & NODE_MASK];
176 
177 	BUG_ON(packet->tlabel > 63 || packet->tlabel < 0);
178 
179         spin_lock_irqsave(&tp->lock, flags);
180 	BUG_ON(!test_and_clear_bit(packet->tlabel, tp->pool));
181         spin_unlock_irqrestore(&tp->lock, flags);
182 
183 	up(&tp->count);
184 }
185 
186 
187 
hpsb_packet_success(struct hpsb_packet * packet)188 int hpsb_packet_success(struct hpsb_packet *packet)
189 {
190         switch (packet->ack_code) {
191         case ACK_PENDING:
192                 switch ((packet->header[1] >> 12) & 0xf) {
193                 case RCODE_COMPLETE:
194                         return 0;
195                 case RCODE_CONFLICT_ERROR:
196                         return -EAGAIN;
197                 case RCODE_DATA_ERROR:
198                         return -EREMOTEIO;
199                 case RCODE_TYPE_ERROR:
200                         return -EACCES;
201                 case RCODE_ADDRESS_ERROR:
202                         return -EINVAL;
203                 default:
204                         HPSB_ERR("received reserved rcode %d from node %d",
205                                  (packet->header[1] >> 12) & 0xf,
206                                  packet->node_id);
207                         return -EAGAIN;
208                 }
209                 HPSB_PANIC("reached unreachable code 1 in %s", __FUNCTION__);
210 
211         case ACK_BUSY_X:
212         case ACK_BUSY_A:
213         case ACK_BUSY_B:
214                 return -EBUSY;
215 
216         case ACK_TYPE_ERROR:
217                 return -EACCES;
218 
219         case ACK_COMPLETE:
220                 if (packet->tcode == TCODE_WRITEQ
221                     || packet->tcode == TCODE_WRITEB) {
222                         return 0;
223                 } else {
224                         HPSB_ERR("impossible ack_complete from node %d "
225                                  "(tcode %d)", packet->node_id, packet->tcode);
226                         return -EAGAIN;
227                 }
228 
229 
230         case ACK_DATA_ERROR:
231                 if (packet->tcode == TCODE_WRITEB
232                     || packet->tcode == TCODE_LOCK_REQUEST) {
233                         return -EAGAIN;
234                 } else {
235                         HPSB_ERR("impossible ack_data_error from node %d "
236                                  "(tcode %d)", packet->node_id, packet->tcode);
237                         return -EAGAIN;
238                 }
239 
240         case ACKX_NONE:
241         case ACKX_SEND_ERROR:
242         case ACKX_ABORTED:
243         case ACKX_TIMEOUT:
244                 /* error while sending */
245                 return -EAGAIN;
246 
247         default:
248                 HPSB_ERR("got invalid ack %d from node %d (tcode %d)",
249                          packet->ack_code, packet->node_id, packet->tcode);
250                 return -EAGAIN;
251         }
252 
253         HPSB_PANIC("reached unreachable code 2 in %s", __FUNCTION__);
254 }
255 
hpsb_make_readpacket(struct hpsb_host * host,nodeid_t node,u64 addr,size_t length)256 struct hpsb_packet *hpsb_make_readpacket(struct hpsb_host *host, nodeid_t node,
257 					 u64 addr, size_t length)
258 {
259         struct hpsb_packet *packet;
260 
261 	if (length == 0)
262 		return NULL;
263 
264 	packet = alloc_hpsb_packet(length + (length % 4 ? 4 - (length % 4) : 0));
265 	if (!packet)
266 		return NULL;
267 
268 	packet->host = host;
269 	packet->node_id = node;
270 
271 	if (hpsb_get_tlabel(packet)) {
272 		free_hpsb_packet(packet);
273 		return NULL;
274 	}
275 
276 	if (length == 4)
277 		fill_async_readquad(packet, addr);
278 	else
279 		fill_async_readblock(packet, addr, length);
280 
281 	return packet;
282 }
283 
hpsb_make_writepacket(struct hpsb_host * host,nodeid_t node,u64 addr,quadlet_t * buffer,size_t length)284 struct hpsb_packet *hpsb_make_writepacket (struct hpsb_host *host, nodeid_t node,
285 					   u64 addr, quadlet_t *buffer, size_t length)
286 {
287 	struct hpsb_packet *packet;
288 
289 	if (length == 0)
290 		return NULL;
291 
292 	packet = alloc_hpsb_packet(length + (length % 4 ? 4 - (length % 4) : 0));
293 	if (!packet)
294 		return NULL;
295 
296 	if (length % 4) { /* zero padding bytes */
297 		packet->data[length >> 2] = 0;
298 	}
299 	packet->host = host;
300 	packet->node_id = node;
301 
302 	if (hpsb_get_tlabel(packet)) {
303 		free_hpsb_packet(packet);
304 		return NULL;
305 	}
306 
307 	if (length == 4) {
308 		fill_async_writequad(packet, addr, buffer ? *buffer : 0);
309 	} else {
310 		fill_async_writeblock(packet, addr, length);
311 		if (buffer)
312 			memcpy(packet->data, buffer, length);
313 	}
314 
315 	return packet;
316 }
317 
hpsb_make_streampacket(struct hpsb_host * host,u8 * buffer,int length,int channel,int tag,int sync)318 struct hpsb_packet *hpsb_make_streampacket(struct hpsb_host *host, u8 *buffer, int length,
319                                            int channel, int tag, int sync)
320 {
321 	struct hpsb_packet *packet;
322 
323 	if (length == 0)
324 		return NULL;
325 
326 	packet = alloc_hpsb_packet(length + (length % 4 ? 4 - (length % 4) : 0));
327 	if (!packet)
328 		return NULL;
329 
330 	if (length % 4) { /* zero padding bytes */
331 		packet->data[length >> 2] = 0;
332 	}
333 	packet->host = host;
334 
335 	if (hpsb_get_tlabel(packet)) {
336 		free_hpsb_packet(packet);
337 		return NULL;
338 	}
339 
340 	fill_async_stream_packet(packet, length, channel, tag, sync);
341 	if (buffer)
342 		memcpy(packet->data, buffer, length);
343 
344 	return packet;
345 }
346 
hpsb_make_lockpacket(struct hpsb_host * host,nodeid_t node,u64 addr,int extcode,quadlet_t * data,quadlet_t arg)347 struct hpsb_packet *hpsb_make_lockpacket(struct hpsb_host *host, nodeid_t node,
348                                          u64 addr, int extcode, quadlet_t *data,
349 					 quadlet_t arg)
350 {
351 	struct hpsb_packet *p;
352 	u32 length;
353 
354 	p = alloc_hpsb_packet(8);
355 	if (!p) return NULL;
356 
357 	p->host = host;
358 	p->node_id = node;
359 	if (hpsb_get_tlabel(p)) {
360 		free_hpsb_packet(p);
361 		return NULL;
362 	}
363 
364 	switch (extcode) {
365 	case EXTCODE_FETCH_ADD:
366 	case EXTCODE_LITTLE_ADD:
367 		length = 4;
368 		if (data)
369 			p->data[0] = *data;
370 		break;
371 	default:
372 		length = 8;
373 		if (data) {
374 			p->data[0] = arg;
375 			p->data[1] = *data;
376 		}
377 		break;
378 	}
379 	fill_async_lock(p, addr, extcode, length);
380 
381 	return p;
382 }
383 
hpsb_make_lock64packet(struct hpsb_host * host,nodeid_t node,u64 addr,int extcode,octlet_t * data,octlet_t arg)384 struct hpsb_packet *hpsb_make_lock64packet(struct hpsb_host *host, nodeid_t node,
385                                            u64 addr, int extcode, octlet_t *data,
386 					   octlet_t arg)
387 {
388 	struct hpsb_packet *p;
389 	u32 length;
390 
391 	p = alloc_hpsb_packet(16);
392 	if (!p) return NULL;
393 
394 	p->host = host;
395 	p->node_id = node;
396 	if (hpsb_get_tlabel(p)) {
397 		free_hpsb_packet(p);
398 		return NULL;
399 	}
400 
401 	switch (extcode) {
402 	case EXTCODE_FETCH_ADD:
403 	case EXTCODE_LITTLE_ADD:
404 		length = 8;
405 		if (data) {
406 			p->data[0] = *data >> 32;
407 			p->data[1] = *data & 0xffffffff;
408 		}
409 		break;
410 	default:
411 		length = 16;
412 		if (data) {
413 			p->data[0] = arg >> 32;
414 			p->data[1] = arg & 0xffffffff;
415 			p->data[2] = *data >> 32;
416 			p->data[3] = *data & 0xffffffff;
417 		}
418 		break;
419 	}
420 	fill_async_lock(p, addr, extcode, length);
421 
422 	return p;
423 }
424 
hpsb_make_phypacket(struct hpsb_host * host,quadlet_t data)425 struct hpsb_packet *hpsb_make_phypacket(struct hpsb_host *host,
426                                         quadlet_t data)
427 {
428         struct hpsb_packet *p;
429 
430         p = alloc_hpsb_packet(0);
431         if (!p) return NULL;
432 
433         p->host = host;
434         fill_phy_packet(p, data);
435 
436         return p;
437 }
438 
hpsb_make_isopacket(struct hpsb_host * host,int length,int channel,int tag,int sync)439 struct hpsb_packet *hpsb_make_isopacket(struct hpsb_host *host,
440 					int length, int channel,
441 					int tag, int sync)
442 {
443 	struct hpsb_packet *p;
444 
445 	p = alloc_hpsb_packet(length);
446 	if (!p) return NULL;
447 
448 	p->host = host;
449 	fill_iso_packet(p, length, channel, tag, sync);
450 
451 	p->generation = get_hpsb_generation(host);
452 
453 	return p;
454 }
455 
456 /*
457  * FIXME - these functions should probably read from / write to user space to
458  * avoid in kernel buffers for user space callers
459  */
460 
hpsb_read(struct hpsb_host * host,nodeid_t node,unsigned int generation,u64 addr,quadlet_t * buffer,size_t length)461 int hpsb_read(struct hpsb_host *host, nodeid_t node, unsigned int generation,
462 	      u64 addr, quadlet_t *buffer, size_t length)
463 {
464         struct hpsb_packet *packet;
465         int retval = 0;
466 
467         if (length == 0)
468                 return -EINVAL;
469 
470 	BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
471 
472 	packet = hpsb_make_readpacket(host, node, addr, length);
473 
474         if (!packet) {
475                 return -ENOMEM;
476         }
477 
478 	packet->generation = generation;
479         if (!hpsb_send_packet(packet)) {
480 		retval = -EINVAL;
481 		goto hpsb_read_fail;
482 	}
483 
484         down(&packet->state_change);
485         down(&packet->state_change);
486         retval = hpsb_packet_success(packet);
487 
488         if (retval == 0) {
489                 if (length == 4) {
490                         *buffer = packet->header[3];
491                 } else {
492                         memcpy(buffer, packet->data, length);
493                 }
494         }
495 
496 hpsb_read_fail:
497         hpsb_free_tlabel(packet);
498         free_hpsb_packet(packet);
499 
500         return retval;
501 }
502 
503 
hpsb_write(struct hpsb_host * host,nodeid_t node,unsigned int generation,u64 addr,quadlet_t * buffer,size_t length)504 int hpsb_write(struct hpsb_host *host, nodeid_t node, unsigned int generation,
505 	       u64 addr, quadlet_t *buffer, size_t length)
506 {
507 	struct hpsb_packet *packet;
508 	int retval;
509 
510 	if (length == 0)
511 		return -EINVAL;
512 
513 	BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
514 
515 	packet = hpsb_make_writepacket (host, node, addr, buffer, length);
516 
517 	if (!packet)
518 		return -ENOMEM;
519 
520 	packet->generation = generation;
521         if (!hpsb_send_packet(packet)) {
522 		retval = -EINVAL;
523 		goto hpsb_write_fail;
524 	}
525 
526         down(&packet->state_change);
527         down(&packet->state_change);
528         retval = hpsb_packet_success(packet);
529 
530 hpsb_write_fail:
531         hpsb_free_tlabel(packet);
532         free_hpsb_packet(packet);
533 
534         return retval;
535 }
536 
537 
hpsb_lock(struct hpsb_host * host,nodeid_t node,unsigned int generation,u64 addr,int extcode,quadlet_t * data,quadlet_t arg)538 int hpsb_lock(struct hpsb_host *host, nodeid_t node, unsigned int generation,
539 	      u64 addr, int extcode, quadlet_t *data, quadlet_t arg)
540 {
541         struct hpsb_packet *packet;
542         int retval = 0;
543 
544 	BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
545 
546 	packet = hpsb_make_lockpacket(host, node, addr, extcode, data, arg);
547         if (!packet)
548                 return -ENOMEM;
549 
550 	packet->generation = generation;
551         if (!hpsb_send_packet(packet)) {
552 		retval = -EINVAL;
553 		goto hpsb_lock_fail;
554 	}
555         down(&packet->state_change);
556         down(&packet->state_change);
557         retval = hpsb_packet_success(packet);
558 
559         if (retval == 0) {
560                 *data = packet->data[0];
561         }
562 
563 hpsb_lock_fail:
564         hpsb_free_tlabel(packet);
565         free_hpsb_packet(packet);
566 
567         return retval;
568 }
569 
hpsb_lock64(struct hpsb_host * host,nodeid_t node,unsigned int generation,u64 addr,int extcode,octlet_t * data,octlet_t arg)570 int hpsb_lock64(struct hpsb_host *host, nodeid_t node, unsigned int generation,
571 		u64 addr, int extcode, octlet_t *data, octlet_t arg)
572 {
573 	struct hpsb_packet *packet;
574 	int retval = 0;
575 
576 	BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
577 
578 	packet = hpsb_make_lock64packet(host, node, addr, extcode, data, arg);
579 	if (!packet)
580 		return -ENOMEM;
581 
582 	packet->generation = generation;
583 	if (!hpsb_send_packet(packet)) {
584 		retval = -EINVAL;
585 		goto hpsb_lock64_fail;
586 	}
587 	down(&packet->state_change);
588 	down(&packet->state_change);
589 	retval = hpsb_packet_success(packet);
590 
591 	if (retval == 0)
592 		*data = (u64)packet->data[1] << 32 | packet->data[0];
593 
594 hpsb_lock64_fail:
595 	hpsb_free_tlabel(packet);
596 	free_hpsb_packet(packet);
597 
598         return retval;
599 }
600 
hpsb_send_gasp(struct hpsb_host * host,int channel,unsigned int generation,quadlet_t * buffer,size_t length,u32 specifier_id,unsigned int version)601 int hpsb_send_gasp(struct hpsb_host *host, int channel, unsigned int generation,
602 		   quadlet_t *buffer, size_t length, u32 specifier_id,
603 		   unsigned int version)
604 {
605 	struct hpsb_packet *packet;
606 	int retval = 0;
607 	u16 specifier_id_hi = (specifier_id & 0x00ffff00) >> 8;
608 	u8 specifier_id_lo = specifier_id & 0xff;
609 
610 	HPSB_VERBOSE("Send GASP: channel = %d, length = %Zd", channel, length);
611 
612 	length += 8;
613 
614 	packet = hpsb_make_streampacket(host, NULL, length, channel, 3, 0);
615 	if (!packet)
616 		return -ENOMEM;
617 
618 	packet->data[0] = cpu_to_be32((host->node_id << 16) | specifier_id_hi);
619 	packet->data[1] = cpu_to_be32((specifier_id_lo << 24) | (version & 0x00ffffff));
620 
621 	memcpy(&(packet->data[2]), buffer, length - 8);
622 
623 	packet->generation = generation;
624 
625 	packet->no_waiter = 1;
626 
627 	if (!hpsb_send_packet(packet)) {
628 		free_hpsb_packet(packet);
629 		retval = -EINVAL;
630 	}
631 
632 	return retval;
633 }
634