firewire: fix libdc1394/FlyCap2 iso event regression
[linux-3.10.git] / drivers / firewire / core-transaction.c
1 /*
2  * Core IEEE1394 transaction logic
3  *
4  * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20
21 #include <linux/bug.h>
22 #include <linux/completion.h>
23 #include <linux/device.h>
24 #include <linux/errno.h>
25 #include <linux/firewire.h>
26 #include <linux/firewire-constants.h>
27 #include <linux/fs.h>
28 #include <linux/init.h>
29 #include <linux/idr.h>
30 #include <linux/jiffies.h>
31 #include <linux/kernel.h>
32 #include <linux/list.h>
33 #include <linux/module.h>
34 #include <linux/rculist.h>
35 #include <linux/slab.h>
36 #include <linux/spinlock.h>
37 #include <linux/string.h>
38 #include <linux/timer.h>
39 #include <linux/types.h>
40 #include <linux/workqueue.h>
41
42 #include <asm/byteorder.h>
43
44 #include "core.h"
45
46 #define HEADER_PRI(pri)                 ((pri) << 0)
47 #define HEADER_TCODE(tcode)             ((tcode) << 4)
48 #define HEADER_RETRY(retry)             ((retry) << 8)
49 #define HEADER_TLABEL(tlabel)           ((tlabel) << 10)
50 #define HEADER_DESTINATION(destination) ((destination) << 16)
51 #define HEADER_SOURCE(source)           ((source) << 16)
52 #define HEADER_RCODE(rcode)             ((rcode) << 12)
53 #define HEADER_OFFSET_HIGH(offset_high) ((offset_high) << 0)
54 #define HEADER_DATA_LENGTH(length)      ((length) << 16)
55 #define HEADER_EXTENDED_TCODE(tcode)    ((tcode) << 0)
56
57 #define HEADER_GET_TCODE(q)             (((q) >> 4) & 0x0f)
58 #define HEADER_GET_TLABEL(q)            (((q) >> 10) & 0x3f)
59 #define HEADER_GET_RCODE(q)             (((q) >> 12) & 0x0f)
60 #define HEADER_GET_DESTINATION(q)       (((q) >> 16) & 0xffff)
61 #define HEADER_GET_SOURCE(q)            (((q) >> 16) & 0xffff)
62 #define HEADER_GET_OFFSET_HIGH(q)       (((q) >> 0) & 0xffff)
63 #define HEADER_GET_DATA_LENGTH(q)       (((q) >> 16) & 0xffff)
64 #define HEADER_GET_EXTENDED_TCODE(q)    (((q) >> 0) & 0xffff)
65
66 #define HEADER_DESTINATION_IS_BROADCAST(q) \
67         (((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
68
69 #define PHY_PACKET_CONFIG       0x0
70 #define PHY_PACKET_LINK_ON      0x1
71 #define PHY_PACKET_SELF_ID      0x2
72
73 #define PHY_CONFIG_GAP_COUNT(gap_count) (((gap_count) << 16) | (1 << 22))
74 #define PHY_CONFIG_ROOT_ID(node_id)     ((((node_id) & 0x3f) << 24) | (1 << 23))
75 #define PHY_IDENTIFIER(id)              ((id) << 30)
76
77 /* returns 0 if the split timeout handler is already running */
78 static int try_cancel_split_timeout(struct fw_transaction *t)
79 {
80         if (t->is_split_transaction)
81                 return del_timer(&t->split_timeout_timer);
82         else
83                 return 1;
84 }
85
86 static int close_transaction(struct fw_transaction *transaction,
87                              struct fw_card *card, int rcode)
88 {
89         struct fw_transaction *t;
90         unsigned long flags;
91
92         spin_lock_irqsave(&card->lock, flags);
93         list_for_each_entry(t, &card->transaction_list, link) {
94                 if (t == transaction) {
95                         if (!try_cancel_split_timeout(t)) {
96                                 spin_unlock_irqrestore(&card->lock, flags);
97                                 goto timed_out;
98                         }
99                         list_del_init(&t->link);
100                         card->tlabel_mask &= ~(1ULL << t->tlabel);
101                         break;
102                 }
103         }
104         spin_unlock_irqrestore(&card->lock, flags);
105
106         if (&t->link != &card->transaction_list) {
107                 t->callback(card, rcode, NULL, 0, t->callback_data);
108                 return 0;
109         }
110
111  timed_out:
112         return -ENOENT;
113 }
114
115 /*
116  * Only valid for transactions that are potentially pending (ie have
117  * been sent).
118  */
119 int fw_cancel_transaction(struct fw_card *card,
120                           struct fw_transaction *transaction)
121 {
122         /*
123          * Cancel the packet transmission if it's still queued.  That
124          * will call the packet transmission callback which cancels
125          * the transaction.
126          */
127
128         if (card->driver->cancel_packet(card, &transaction->packet) == 0)
129                 return 0;
130
131         /*
132          * If the request packet has already been sent, we need to see
133          * if the transaction is still pending and remove it in that case.
134          */
135
136         return close_transaction(transaction, card, RCODE_CANCELLED);
137 }
138 EXPORT_SYMBOL(fw_cancel_transaction);
139
140 static void split_transaction_timeout_callback(unsigned long data)
141 {
142         struct fw_transaction *t = (struct fw_transaction *)data;
143         struct fw_card *card = t->card;
144         unsigned long flags;
145
146         spin_lock_irqsave(&card->lock, flags);
147         if (list_empty(&t->link)) {
148                 spin_unlock_irqrestore(&card->lock, flags);
149                 return;
150         }
151         list_del(&t->link);
152         card->tlabel_mask &= ~(1ULL << t->tlabel);
153         spin_unlock_irqrestore(&card->lock, flags);
154
155         t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
156 }
157
158 static void start_split_transaction_timeout(struct fw_transaction *t,
159                                             struct fw_card *card)
160 {
161         unsigned long flags;
162
163         spin_lock_irqsave(&card->lock, flags);
164
165         if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
166                 spin_unlock_irqrestore(&card->lock, flags);
167                 return;
168         }
169
170         t->is_split_transaction = true;
171         mod_timer(&t->split_timeout_timer,
172                   jiffies + card->split_timeout_jiffies);
173
174         spin_unlock_irqrestore(&card->lock, flags);
175 }
176
177 static void transmit_complete_callback(struct fw_packet *packet,
178                                        struct fw_card *card, int status)
179 {
180         struct fw_transaction *t =
181             container_of(packet, struct fw_transaction, packet);
182
183         switch (status) {
184         case ACK_COMPLETE:
185                 close_transaction(t, card, RCODE_COMPLETE);
186                 break;
187         case ACK_PENDING:
188                 start_split_transaction_timeout(t, card);
189                 break;
190         case ACK_BUSY_X:
191         case ACK_BUSY_A:
192         case ACK_BUSY_B:
193                 close_transaction(t, card, RCODE_BUSY);
194                 break;
195         case ACK_DATA_ERROR:
196                 close_transaction(t, card, RCODE_DATA_ERROR);
197                 break;
198         case ACK_TYPE_ERROR:
199                 close_transaction(t, card, RCODE_TYPE_ERROR);
200                 break;
201         default:
202                 /*
203                  * In this case the ack is really a juju specific
204                  * rcode, so just forward that to the callback.
205                  */
206                 close_transaction(t, card, status);
207                 break;
208         }
209 }
210
211 static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
212                 int destination_id, int source_id, int generation, int speed,
213                 unsigned long long offset, void *payload, size_t length)
214 {
215         int ext_tcode;
216
217         if (tcode == TCODE_STREAM_DATA) {
218                 packet->header[0] =
219                         HEADER_DATA_LENGTH(length) |
220                         destination_id |
221                         HEADER_TCODE(TCODE_STREAM_DATA);
222                 packet->header_length = 4;
223                 packet->payload = payload;
224                 packet->payload_length = length;
225
226                 goto common;
227         }
228
229         if (tcode > 0x10) {
230                 ext_tcode = tcode & ~0x10;
231                 tcode = TCODE_LOCK_REQUEST;
232         } else
233                 ext_tcode = 0;
234
235         packet->header[0] =
236                 HEADER_RETRY(RETRY_X) |
237                 HEADER_TLABEL(tlabel) |
238                 HEADER_TCODE(tcode) |
239                 HEADER_DESTINATION(destination_id);
240         packet->header[1] =
241                 HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
242         packet->header[2] =
243                 offset;
244
245         switch (tcode) {
246         case TCODE_WRITE_QUADLET_REQUEST:
247                 packet->header[3] = *(u32 *)payload;
248                 packet->header_length = 16;
249                 packet->payload_length = 0;
250                 break;
251
252         case TCODE_LOCK_REQUEST:
253         case TCODE_WRITE_BLOCK_REQUEST:
254                 packet->header[3] =
255                         HEADER_DATA_LENGTH(length) |
256                         HEADER_EXTENDED_TCODE(ext_tcode);
257                 packet->header_length = 16;
258                 packet->payload = payload;
259                 packet->payload_length = length;
260                 break;
261
262         case TCODE_READ_QUADLET_REQUEST:
263                 packet->header_length = 12;
264                 packet->payload_length = 0;
265                 break;
266
267         case TCODE_READ_BLOCK_REQUEST:
268                 packet->header[3] =
269                         HEADER_DATA_LENGTH(length) |
270                         HEADER_EXTENDED_TCODE(ext_tcode);
271                 packet->header_length = 16;
272                 packet->payload_length = 0;
273                 break;
274
275         default:
276                 WARN(1, "wrong tcode %d\n", tcode);
277         }
278  common:
279         packet->speed = speed;
280         packet->generation = generation;
281         packet->ack = 0;
282         packet->payload_mapped = false;
283 }
284
285 static int allocate_tlabel(struct fw_card *card)
286 {
287         int tlabel;
288
289         tlabel = card->current_tlabel;
290         while (card->tlabel_mask & (1ULL << tlabel)) {
291                 tlabel = (tlabel + 1) & 0x3f;
292                 if (tlabel == card->current_tlabel)
293                         return -EBUSY;
294         }
295
296         card->current_tlabel = (tlabel + 1) & 0x3f;
297         card->tlabel_mask |= 1ULL << tlabel;
298
299         return tlabel;
300 }
301
302 /**
303  * fw_send_request() - submit a request packet for transmission
304  * @card:               interface to send the request at
305  * @t:                  transaction instance to which the request belongs
306  * @tcode:              transaction code
307  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
308  * @generation:         bus generation in which request and response are valid
309  * @speed:              transmission speed
310  * @offset:             48bit wide offset into destination's address space
311  * @payload:            data payload for the request subaction
312  * @length:             length of the payload, in bytes
313  * @callback:           function to be called when the transaction is completed
314  * @callback_data:      data to be passed to the transaction completion callback
315  *
316  * Submit a request packet into the asynchronous request transmission queue.
317  * Can be called from atomic context.  If you prefer a blocking API, use
318  * fw_run_transaction() in a context that can sleep.
319  *
320  * In case of lock requests, specify one of the firewire-core specific %TCODE_
321  * constants instead of %TCODE_LOCK_REQUEST in @tcode.
322  *
323  * Make sure that the value in @destination_id is not older than the one in
324  * @generation.  Otherwise the request is in danger to be sent to a wrong node.
325  *
326  * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
327  * needs to synthesize @destination_id with fw_stream_packet_destination_id().
328  * It will contain tag, channel, and sy data instead of a node ID then.
329  *
330  * The payload buffer at @data is going to be DMA-mapped except in case of
331  * @length <= 8 or of local (loopback) requests.  Hence make sure that the
332  * buffer complies with the restrictions of the streaming DMA mapping API.
333  * @payload must not be freed before the @callback is called.
334  *
335  * In case of request types without payload, @data is NULL and @length is 0.
336  *
337  * After the transaction is completed successfully or unsuccessfully, the
338  * @callback will be called.  Among its parameters is the response code which
339  * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
340  * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
341  * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
342  * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
343  * generation, or missing ACK respectively.
344  *
345  * Note some timing corner cases:  fw_send_request() may complete much earlier
346  * than when the request packet actually hits the wire.  On the other hand,
347  * transaction completion and hence execution of @callback may happen even
348  * before fw_send_request() returns.
349  */
350 void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
351                      int destination_id, int generation, int speed,
352                      unsigned long long offset, void *payload, size_t length,
353                      fw_transaction_callback_t callback, void *callback_data)
354 {
355         unsigned long flags;
356         int tlabel;
357
358         /*
359          * Allocate tlabel from the bitmap and put the transaction on
360          * the list while holding the card spinlock.
361          */
362
363         spin_lock_irqsave(&card->lock, flags);
364
365         tlabel = allocate_tlabel(card);
366         if (tlabel < 0) {
367                 spin_unlock_irqrestore(&card->lock, flags);
368                 callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
369                 return;
370         }
371
372         t->node_id = destination_id;
373         t->tlabel = tlabel;
374         t->card = card;
375         t->is_split_transaction = false;
376         setup_timer(&t->split_timeout_timer,
377                     split_transaction_timeout_callback, (unsigned long)t);
378         t->callback = callback;
379         t->callback_data = callback_data;
380
381         fw_fill_request(&t->packet, tcode, t->tlabel,
382                         destination_id, card->node_id, generation,
383                         speed, offset, payload, length);
384         t->packet.callback = transmit_complete_callback;
385
386         list_add_tail(&t->link, &card->transaction_list);
387
388         spin_unlock_irqrestore(&card->lock, flags);
389
390         card->driver->send_request(card, &t->packet);
391 }
392 EXPORT_SYMBOL(fw_send_request);
393
394 struct transaction_callback_data {
395         struct completion done;
396         void *payload;
397         int rcode;
398 };
399
400 static void transaction_callback(struct fw_card *card, int rcode,
401                                  void *payload, size_t length, void *data)
402 {
403         struct transaction_callback_data *d = data;
404
405         if (rcode == RCODE_COMPLETE)
406                 memcpy(d->payload, payload, length);
407         d->rcode = rcode;
408         complete(&d->done);
409 }
410
411 /**
412  * fw_run_transaction() - send request and sleep until transaction is completed
413  *
414  * Returns the RCODE.  See fw_send_request() for parameter documentation.
415  * Unlike fw_send_request(), @data points to the payload of the request or/and
416  * to the payload of the response.  DMA mapping restrictions apply to outbound
417  * request payloads of >= 8 bytes but not to inbound response payloads.
418  */
419 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
420                        int generation, int speed, unsigned long long offset,
421                        void *payload, size_t length)
422 {
423         struct transaction_callback_data d;
424         struct fw_transaction t;
425
426         init_timer_on_stack(&t.split_timeout_timer);
427         init_completion(&d.done);
428         d.payload = payload;
429         fw_send_request(card, &t, tcode, destination_id, generation, speed,
430                         offset, payload, length, transaction_callback, &d);
431         wait_for_completion(&d.done);
432         destroy_timer_on_stack(&t.split_timeout_timer);
433
434         return d.rcode;
435 }
436 EXPORT_SYMBOL(fw_run_transaction);
437
438 static DEFINE_MUTEX(phy_config_mutex);
439 static DECLARE_COMPLETION(phy_config_done);
440
441 static void transmit_phy_packet_callback(struct fw_packet *packet,
442                                          struct fw_card *card, int status)
443 {
444         complete(&phy_config_done);
445 }
446
447 static struct fw_packet phy_config_packet = {
448         .header_length  = 12,
449         .header[0]      = TCODE_LINK_INTERNAL << 4,
450         .payload_length = 0,
451         .speed          = SCODE_100,
452         .callback       = transmit_phy_packet_callback,
453 };
454
455 void fw_send_phy_config(struct fw_card *card,
456                         int node_id, int generation, int gap_count)
457 {
458         long timeout = DIV_ROUND_UP(HZ, 10);
459         u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
460
461         if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
462                 data |= PHY_CONFIG_ROOT_ID(node_id);
463
464         if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
465                 gap_count = card->driver->read_phy_reg(card, 1);
466                 if (gap_count < 0)
467                         return;
468
469                 gap_count &= 63;
470                 if (gap_count == 63)
471                         return;
472         }
473         data |= PHY_CONFIG_GAP_COUNT(gap_count);
474
475         mutex_lock(&phy_config_mutex);
476
477         phy_config_packet.header[1] = data;
478         phy_config_packet.header[2] = ~data;
479         phy_config_packet.generation = generation;
480         INIT_COMPLETION(phy_config_done);
481
482         card->driver->send_request(card, &phy_config_packet);
483         wait_for_completion_timeout(&phy_config_done, timeout);
484
485         mutex_unlock(&phy_config_mutex);
486 }
487
488 static struct fw_address_handler *lookup_overlapping_address_handler(
489         struct list_head *list, unsigned long long offset, size_t length)
490 {
491         struct fw_address_handler *handler;
492
493         list_for_each_entry_rcu(handler, list, link) {
494                 if (handler->offset < offset + length &&
495                     offset < handler->offset + handler->length)
496                         return handler;
497         }
498
499         return NULL;
500 }
501
502 static bool is_enclosing_handler(struct fw_address_handler *handler,
503                                  unsigned long long offset, size_t length)
504 {
505         return handler->offset <= offset &&
506                 offset + length <= handler->offset + handler->length;
507 }
508
509 static struct fw_address_handler *lookup_enclosing_address_handler(
510         struct list_head *list, unsigned long long offset, size_t length)
511 {
512         struct fw_address_handler *handler;
513
514         list_for_each_entry_rcu(handler, list, link) {
515                 if (is_enclosing_handler(handler, offset, length))
516                         return handler;
517         }
518
519         return NULL;
520 }
521
522 static DEFINE_SPINLOCK(address_handler_list_lock);
523 static LIST_HEAD(address_handler_list);
524
525 const struct fw_address_region fw_high_memory_region =
526         { .start = 0x000100000000ULL, .end = 0xffffe0000000ULL,  };
527 EXPORT_SYMBOL(fw_high_memory_region);
528
529 static const struct fw_address_region low_memory_region =
530         { .start = 0x000000000000ULL, .end = 0x000100000000ULL,  };
531
532 #if 0
533 const struct fw_address_region fw_private_region =
534         { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
535 const struct fw_address_region fw_csr_region =
536         { .start = CSR_REGISTER_BASE,
537           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
538 const struct fw_address_region fw_unit_space_region =
539         { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
540 #endif  /*  0  */
541
542 static bool is_in_fcp_region(u64 offset, size_t length)
543 {
544         return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
545                 offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
546 }
547
548 /**
549  * fw_core_add_address_handler() - register for incoming requests
550  * @handler:    callback
551  * @region:     region in the IEEE 1212 node space address range
552  *
553  * region->start, ->end, and handler->length have to be quadlet-aligned.
554  *
555  * When a request is received that falls within the specified address range,
556  * the specified callback is invoked.  The parameters passed to the callback
557  * give the details of the particular request.
558  *
559  * To be called in process context.
560  * Return value:  0 on success, non-zero otherwise.
561  *
562  * The start offset of the handler's address region is determined by
563  * fw_core_add_address_handler() and is returned in handler->offset.
564  *
565  * Address allocations are exclusive, except for the FCP registers.
566  */
567 int fw_core_add_address_handler(struct fw_address_handler *handler,
568                                 const struct fw_address_region *region)
569 {
570         struct fw_address_handler *other;
571         int ret = -EBUSY;
572
573         if (region->start & 0xffff000000000003ULL ||
574             region->start >= region->end ||
575             region->end   > 0x0001000000000000ULL ||
576             handler->length & 3 ||
577             handler->length == 0)
578                 return -EINVAL;
579
580         spin_lock(&address_handler_list_lock);
581
582         handler->offset = region->start;
583         while (handler->offset + handler->length <= region->end) {
584                 if (is_in_fcp_region(handler->offset, handler->length))
585                         other = NULL;
586                 else
587                         other = lookup_overlapping_address_handler
588                                         (&address_handler_list,
589                                          handler->offset, handler->length);
590                 if (other != NULL) {
591                         handler->offset += other->length;
592                 } else {
593                         list_add_tail_rcu(&handler->link, &address_handler_list);
594                         ret = 0;
595                         break;
596                 }
597         }
598
599         spin_unlock(&address_handler_list_lock);
600
601         return ret;
602 }
603 EXPORT_SYMBOL(fw_core_add_address_handler);
604
605 /**
606  * fw_core_remove_address_handler() - unregister an address handler
607  *
608  * To be called in process context.
609  *
610  * When fw_core_remove_address_handler() returns, @handler->callback() is
611  * guaranteed to not run on any CPU anymore.
612  */
613 void fw_core_remove_address_handler(struct fw_address_handler *handler)
614 {
615         spin_lock(&address_handler_list_lock);
616         list_del_rcu(&handler->link);
617         spin_unlock(&address_handler_list_lock);
618         synchronize_rcu();
619 }
620 EXPORT_SYMBOL(fw_core_remove_address_handler);
621
622 struct fw_request {
623         struct fw_packet response;
624         u32 request_header[4];
625         int ack;
626         u32 length;
627         u32 data[0];
628 };
629
630 static void free_response_callback(struct fw_packet *packet,
631                                    struct fw_card *card, int status)
632 {
633         struct fw_request *request;
634
635         request = container_of(packet, struct fw_request, response);
636         kfree(request);
637 }
638
639 int fw_get_response_length(struct fw_request *r)
640 {
641         int tcode, ext_tcode, data_length;
642
643         tcode = HEADER_GET_TCODE(r->request_header[0]);
644
645         switch (tcode) {
646         case TCODE_WRITE_QUADLET_REQUEST:
647         case TCODE_WRITE_BLOCK_REQUEST:
648                 return 0;
649
650         case TCODE_READ_QUADLET_REQUEST:
651                 return 4;
652
653         case TCODE_READ_BLOCK_REQUEST:
654                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
655                 return data_length;
656
657         case TCODE_LOCK_REQUEST:
658                 ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
659                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
660                 switch (ext_tcode) {
661                 case EXTCODE_FETCH_ADD:
662                 case EXTCODE_LITTLE_ADD:
663                         return data_length;
664                 default:
665                         return data_length / 2;
666                 }
667
668         default:
669                 WARN(1, "wrong tcode %d\n", tcode);
670                 return 0;
671         }
672 }
673
674 void fw_fill_response(struct fw_packet *response, u32 *request_header,
675                       int rcode, void *payload, size_t length)
676 {
677         int tcode, tlabel, extended_tcode, source, destination;
678
679         tcode          = HEADER_GET_TCODE(request_header[0]);
680         tlabel         = HEADER_GET_TLABEL(request_header[0]);
681         source         = HEADER_GET_DESTINATION(request_header[0]);
682         destination    = HEADER_GET_SOURCE(request_header[1]);
683         extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
684
685         response->header[0] =
686                 HEADER_RETRY(RETRY_1) |
687                 HEADER_TLABEL(tlabel) |
688                 HEADER_DESTINATION(destination);
689         response->header[1] =
690                 HEADER_SOURCE(source) |
691                 HEADER_RCODE(rcode);
692         response->header[2] = 0;
693
694         switch (tcode) {
695         case TCODE_WRITE_QUADLET_REQUEST:
696         case TCODE_WRITE_BLOCK_REQUEST:
697                 response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
698                 response->header_length = 12;
699                 response->payload_length = 0;
700                 break;
701
702         case TCODE_READ_QUADLET_REQUEST:
703                 response->header[0] |=
704                         HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
705                 if (payload != NULL)
706                         response->header[3] = *(u32 *)payload;
707                 else
708                         response->header[3] = 0;
709                 response->header_length = 16;
710                 response->payload_length = 0;
711                 break;
712
713         case TCODE_READ_BLOCK_REQUEST:
714         case TCODE_LOCK_REQUEST:
715                 response->header[0] |= HEADER_TCODE(tcode + 2);
716                 response->header[3] =
717                         HEADER_DATA_LENGTH(length) |
718                         HEADER_EXTENDED_TCODE(extended_tcode);
719                 response->header_length = 16;
720                 response->payload = payload;
721                 response->payload_length = length;
722                 break;
723
724         default:
725                 WARN(1, "wrong tcode %d\n", tcode);
726         }
727
728         response->payload_mapped = false;
729 }
730 EXPORT_SYMBOL(fw_fill_response);
731
732 static u32 compute_split_timeout_timestamp(struct fw_card *card,
733                                            u32 request_timestamp)
734 {
735         unsigned int cycles;
736         u32 timestamp;
737
738         cycles = card->split_timeout_cycles;
739         cycles += request_timestamp & 0x1fff;
740
741         timestamp = request_timestamp & ~0x1fff;
742         timestamp += (cycles / 8000) << 13;
743         timestamp |= cycles % 8000;
744
745         return timestamp;
746 }
747
748 static struct fw_request *allocate_request(struct fw_card *card,
749                                            struct fw_packet *p)
750 {
751         struct fw_request *request;
752         u32 *data, length;
753         int request_tcode;
754
755         request_tcode = HEADER_GET_TCODE(p->header[0]);
756         switch (request_tcode) {
757         case TCODE_WRITE_QUADLET_REQUEST:
758                 data = &p->header[3];
759                 length = 4;
760                 break;
761
762         case TCODE_WRITE_BLOCK_REQUEST:
763         case TCODE_LOCK_REQUEST:
764                 data = p->payload;
765                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
766                 break;
767
768         case TCODE_READ_QUADLET_REQUEST:
769                 data = NULL;
770                 length = 4;
771                 break;
772
773         case TCODE_READ_BLOCK_REQUEST:
774                 data = NULL;
775                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
776                 break;
777
778         default:
779                 fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
780                          p->header[0], p->header[1], p->header[2]);
781                 return NULL;
782         }
783
784         request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
785         if (request == NULL)
786                 return NULL;
787
788         request->response.speed = p->speed;
789         request->response.timestamp =
790                         compute_split_timeout_timestamp(card, p->timestamp);
791         request->response.generation = p->generation;
792         request->response.ack = 0;
793         request->response.callback = free_response_callback;
794         request->ack = p->ack;
795         request->length = length;
796         if (data)
797                 memcpy(request->data, data, length);
798
799         memcpy(request->request_header, p->header, sizeof(p->header));
800
801         return request;
802 }
803
804 void fw_send_response(struct fw_card *card,
805                       struct fw_request *request, int rcode)
806 {
807         if (WARN_ONCE(!request, "invalid for FCP address handlers"))
808                 return;
809
810         /* unified transaction or broadcast transaction: don't respond */
811         if (request->ack != ACK_PENDING ||
812             HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
813                 kfree(request);
814                 return;
815         }
816
817         if (rcode == RCODE_COMPLETE)
818                 fw_fill_response(&request->response, request->request_header,
819                                  rcode, request->data,
820                                  fw_get_response_length(request));
821         else
822                 fw_fill_response(&request->response, request->request_header,
823                                  rcode, NULL, 0);
824
825         card->driver->send_response(card, &request->response);
826 }
827 EXPORT_SYMBOL(fw_send_response);
828
829 /**
830  * fw_get_request_speed() - returns speed at which the @request was received
831  */
832 int fw_get_request_speed(struct fw_request *request)
833 {
834         return request->response.speed;
835 }
836 EXPORT_SYMBOL(fw_get_request_speed);
837
838 static void handle_exclusive_region_request(struct fw_card *card,
839                                             struct fw_packet *p,
840                                             struct fw_request *request,
841                                             unsigned long long offset)
842 {
843         struct fw_address_handler *handler;
844         int tcode, destination, source;
845
846         destination = HEADER_GET_DESTINATION(p->header[0]);
847         source      = HEADER_GET_SOURCE(p->header[1]);
848         tcode       = HEADER_GET_TCODE(p->header[0]);
849         if (tcode == TCODE_LOCK_REQUEST)
850                 tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
851
852         rcu_read_lock();
853         handler = lookup_enclosing_address_handler(&address_handler_list,
854                                                    offset, request->length);
855         if (handler)
856                 handler->address_callback(card, request,
857                                           tcode, destination, source,
858                                           p->generation, offset,
859                                           request->data, request->length,
860                                           handler->callback_data);
861         rcu_read_unlock();
862
863         if (!handler)
864                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
865 }
866
867 static void handle_fcp_region_request(struct fw_card *card,
868                                       struct fw_packet *p,
869                                       struct fw_request *request,
870                                       unsigned long long offset)
871 {
872         struct fw_address_handler *handler;
873         int tcode, destination, source;
874
875         if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
876              offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
877             request->length > 0x200) {
878                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
879
880                 return;
881         }
882
883         tcode       = HEADER_GET_TCODE(p->header[0]);
884         destination = HEADER_GET_DESTINATION(p->header[0]);
885         source      = HEADER_GET_SOURCE(p->header[1]);
886
887         if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
888             tcode != TCODE_WRITE_BLOCK_REQUEST) {
889                 fw_send_response(card, request, RCODE_TYPE_ERROR);
890
891                 return;
892         }
893
894         rcu_read_lock();
895         list_for_each_entry_rcu(handler, &address_handler_list, link) {
896                 if (is_enclosing_handler(handler, offset, request->length))
897                         handler->address_callback(card, NULL, tcode,
898                                                   destination, source,
899                                                   p->generation, offset,
900                                                   request->data,
901                                                   request->length,
902                                                   handler->callback_data);
903         }
904         rcu_read_unlock();
905
906         fw_send_response(card, request, RCODE_COMPLETE);
907 }
908
909 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
910 {
911         struct fw_request *request;
912         unsigned long long offset;
913
914         if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
915                 return;
916
917         if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
918                 fw_cdev_handle_phy_packet(card, p);
919                 return;
920         }
921
922         request = allocate_request(card, p);
923         if (request == NULL) {
924                 /* FIXME: send statically allocated busy packet. */
925                 return;
926         }
927
928         offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
929                 p->header[2];
930
931         if (!is_in_fcp_region(offset, request->length))
932                 handle_exclusive_region_request(card, p, request, offset);
933         else
934                 handle_fcp_region_request(card, p, request, offset);
935
936 }
937 EXPORT_SYMBOL(fw_core_handle_request);
938
939 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
940 {
941         struct fw_transaction *t;
942         unsigned long flags;
943         u32 *data;
944         size_t data_length;
945         int tcode, tlabel, source, rcode;
946
947         tcode   = HEADER_GET_TCODE(p->header[0]);
948         tlabel  = HEADER_GET_TLABEL(p->header[0]);
949         source  = HEADER_GET_SOURCE(p->header[1]);
950         rcode   = HEADER_GET_RCODE(p->header[1]);
951
952         spin_lock_irqsave(&card->lock, flags);
953         list_for_each_entry(t, &card->transaction_list, link) {
954                 if (t->node_id == source && t->tlabel == tlabel) {
955                         if (!try_cancel_split_timeout(t)) {
956                                 spin_unlock_irqrestore(&card->lock, flags);
957                                 goto timed_out;
958                         }
959                         list_del_init(&t->link);
960                         card->tlabel_mask &= ~(1ULL << t->tlabel);
961                         break;
962                 }
963         }
964         spin_unlock_irqrestore(&card->lock, flags);
965
966         if (&t->link == &card->transaction_list) {
967  timed_out:
968                 fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
969                           source, tlabel);
970                 return;
971         }
972
973         /*
974          * FIXME: sanity check packet, is length correct, does tcodes
975          * and addresses match.
976          */
977
978         switch (tcode) {
979         case TCODE_READ_QUADLET_RESPONSE:
980                 data = (u32 *) &p->header[3];
981                 data_length = 4;
982                 break;
983
984         case TCODE_WRITE_RESPONSE:
985                 data = NULL;
986                 data_length = 0;
987                 break;
988
989         case TCODE_READ_BLOCK_RESPONSE:
990         case TCODE_LOCK_RESPONSE:
991                 data = p->payload;
992                 data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
993                 break;
994
995         default:
996                 /* Should never happen, this is just to shut up gcc. */
997                 data = NULL;
998                 data_length = 0;
999                 break;
1000         }
1001
1002         /*
1003          * The response handler may be executed while the request handler
1004          * is still pending.  Cancel the request handler.
1005          */
1006         card->driver->cancel_packet(card, &t->packet);
1007
1008         t->callback(card, rcode, data, data_length, t->callback_data);
1009 }
1010 EXPORT_SYMBOL(fw_core_handle_response);
1011
1012 /**
1013  * fw_rcode_string - convert a firewire result code to an error description
1014  * @rcode: the result code
1015  */
1016 const char *fw_rcode_string(int rcode)
1017 {
1018         static const char *const names[] = {
1019                 [RCODE_COMPLETE]       = "no error",
1020                 [RCODE_CONFLICT_ERROR] = "conflict error",
1021                 [RCODE_DATA_ERROR]     = "data error",
1022                 [RCODE_TYPE_ERROR]     = "type error",
1023                 [RCODE_ADDRESS_ERROR]  = "address error",
1024                 [RCODE_SEND_ERROR]     = "send error",
1025                 [RCODE_CANCELLED]      = "timeout",
1026                 [RCODE_BUSY]           = "busy",
1027                 [RCODE_GENERATION]     = "bus reset",
1028                 [RCODE_NO_ACK]         = "no ack",
1029         };
1030
1031         if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1032                 return names[rcode];
1033         else
1034                 return "unknown";
1035 }
1036 EXPORT_SYMBOL(fw_rcode_string);
1037
1038 static const struct fw_address_region topology_map_region =
1039         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1040           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1041
1042 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1043                 int tcode, int destination, int source, int generation,
1044                 unsigned long long offset, void *payload, size_t length,
1045                 void *callback_data)
1046 {
1047         int start;
1048
1049         if (!TCODE_IS_READ_REQUEST(tcode)) {
1050                 fw_send_response(card, request, RCODE_TYPE_ERROR);
1051                 return;
1052         }
1053
1054         if ((offset & 3) > 0 || (length & 3) > 0) {
1055                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1056                 return;
1057         }
1058
1059         start = (offset - topology_map_region.start) / 4;
1060         memcpy(payload, &card->topology_map[start], length);
1061
1062         fw_send_response(card, request, RCODE_COMPLETE);
1063 }
1064
1065 static struct fw_address_handler topology_map = {
1066         .length                 = 0x400,
1067         .address_callback       = handle_topology_map,
1068 };
1069
1070 static const struct fw_address_region registers_region =
1071         { .start = CSR_REGISTER_BASE,
1072           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1073
1074 static void update_split_timeout(struct fw_card *card)
1075 {
1076         unsigned int cycles;
1077
1078         cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1079
1080         /* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1081         cycles = clamp(cycles, 800u, 3u * 8000u);
1082
1083         card->split_timeout_cycles = cycles;
1084         card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1085 }
1086
1087 static void handle_registers(struct fw_card *card, struct fw_request *request,
1088                 int tcode, int destination, int source, int generation,
1089                 unsigned long long offset, void *payload, size_t length,
1090                 void *callback_data)
1091 {
1092         int reg = offset & ~CSR_REGISTER_BASE;
1093         __be32 *data = payload;
1094         int rcode = RCODE_COMPLETE;
1095         unsigned long flags;
1096
1097         switch (reg) {
1098         case CSR_PRIORITY_BUDGET:
1099                 if (!card->priority_budget_implemented) {
1100                         rcode = RCODE_ADDRESS_ERROR;
1101                         break;
1102                 }
1103                 /* else fall through */
1104
1105         case CSR_NODE_IDS:
1106                 /*
1107                  * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1108                  * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1109                  */
1110                 /* fall through */
1111
1112         case CSR_STATE_CLEAR:
1113         case CSR_STATE_SET:
1114         case CSR_CYCLE_TIME:
1115         case CSR_BUS_TIME:
1116         case CSR_BUSY_TIMEOUT:
1117                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1118                         *data = cpu_to_be32(card->driver->read_csr(card, reg));
1119                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1120                         card->driver->write_csr(card, reg, be32_to_cpu(*data));
1121                 else
1122                         rcode = RCODE_TYPE_ERROR;
1123                 break;
1124
1125         case CSR_RESET_START:
1126                 if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1127                         card->driver->write_csr(card, CSR_STATE_CLEAR,
1128                                                 CSR_STATE_BIT_ABDICATE);
1129                 else
1130                         rcode = RCODE_TYPE_ERROR;
1131                 break;
1132
1133         case CSR_SPLIT_TIMEOUT_HI:
1134                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1135                         *data = cpu_to_be32(card->split_timeout_hi);
1136                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1137                         spin_lock_irqsave(&card->lock, flags);
1138                         card->split_timeout_hi = be32_to_cpu(*data) & 7;
1139                         update_split_timeout(card);
1140                         spin_unlock_irqrestore(&card->lock, flags);
1141                 } else {
1142                         rcode = RCODE_TYPE_ERROR;
1143                 }
1144                 break;
1145
1146         case CSR_SPLIT_TIMEOUT_LO:
1147                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1148                         *data = cpu_to_be32(card->split_timeout_lo);
1149                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1150                         spin_lock_irqsave(&card->lock, flags);
1151                         card->split_timeout_lo =
1152                                         be32_to_cpu(*data) & 0xfff80000;
1153                         update_split_timeout(card);
1154                         spin_unlock_irqrestore(&card->lock, flags);
1155                 } else {
1156                         rcode = RCODE_TYPE_ERROR;
1157                 }
1158                 break;
1159
1160         case CSR_MAINT_UTILITY:
1161                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1162                         *data = card->maint_utility_register;
1163                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1164                         card->maint_utility_register = *data;
1165                 else
1166                         rcode = RCODE_TYPE_ERROR;
1167                 break;
1168
1169         case CSR_BROADCAST_CHANNEL:
1170                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1171                         *data = cpu_to_be32(card->broadcast_channel);
1172                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1173                         card->broadcast_channel =
1174                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1175                             BROADCAST_CHANNEL_INITIAL;
1176                 else
1177                         rcode = RCODE_TYPE_ERROR;
1178                 break;
1179
1180         case CSR_BUS_MANAGER_ID:
1181         case CSR_BANDWIDTH_AVAILABLE:
1182         case CSR_CHANNELS_AVAILABLE_HI:
1183         case CSR_CHANNELS_AVAILABLE_LO:
1184                 /*
1185                  * FIXME: these are handled by the OHCI hardware and
1186                  * the stack never sees these request. If we add
1187                  * support for a new type of controller that doesn't
1188                  * handle this in hardware we need to deal with these
1189                  * transactions.
1190                  */
1191                 BUG();
1192                 break;
1193
1194         default:
1195                 rcode = RCODE_ADDRESS_ERROR;
1196                 break;
1197         }
1198
1199         fw_send_response(card, request, rcode);
1200 }
1201
1202 static struct fw_address_handler registers = {
1203         .length                 = 0x400,
1204         .address_callback       = handle_registers,
1205 };
1206
1207 static void handle_low_memory(struct fw_card *card, struct fw_request *request,
1208                 int tcode, int destination, int source, int generation,
1209                 unsigned long long offset, void *payload, size_t length,
1210                 void *callback_data)
1211 {
1212         /*
1213          * This catches requests not handled by the physical DMA unit,
1214          * i.e., wrong transaction types or unauthorized source nodes.
1215          */
1216         fw_send_response(card, request, RCODE_TYPE_ERROR);
1217 }
1218
1219 static struct fw_address_handler low_memory = {
1220         .length                 = 0x000100000000ULL,
1221         .address_callback       = handle_low_memory,
1222 };
1223
1224 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1225 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1226 MODULE_LICENSE("GPL");
1227
1228 static const u32 vendor_textual_descriptor[] = {
1229         /* textual descriptor leaf () */
1230         0x00060000,
1231         0x00000000,
1232         0x00000000,
1233         0x4c696e75,             /* L i n u */
1234         0x78204669,             /* x   F i */
1235         0x72657769,             /* r e w i */
1236         0x72650000,             /* r e     */
1237 };
1238
1239 static const u32 model_textual_descriptor[] = {
1240         /* model descriptor leaf () */
1241         0x00030000,
1242         0x00000000,
1243         0x00000000,
1244         0x4a756a75,             /* J u j u */
1245 };
1246
1247 static struct fw_descriptor vendor_id_descriptor = {
1248         .length = ARRAY_SIZE(vendor_textual_descriptor),
1249         .immediate = 0x03d00d1e,
1250         .key = 0x81000000,
1251         .data = vendor_textual_descriptor,
1252 };
1253
1254 static struct fw_descriptor model_id_descriptor = {
1255         .length = ARRAY_SIZE(model_textual_descriptor),
1256         .immediate = 0x17000001,
1257         .key = 0x81000000,
1258         .data = model_textual_descriptor,
1259 };
1260
1261 static int __init fw_core_init(void)
1262 {
1263         int ret;
1264
1265         fw_workqueue = alloc_workqueue("firewire",
1266                                        WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0);
1267         if (!fw_workqueue)
1268                 return -ENOMEM;
1269
1270         ret = bus_register(&fw_bus_type);
1271         if (ret < 0) {
1272                 destroy_workqueue(fw_workqueue);
1273                 return ret;
1274         }
1275
1276         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1277         if (fw_cdev_major < 0) {
1278                 bus_unregister(&fw_bus_type);
1279                 destroy_workqueue(fw_workqueue);
1280                 return fw_cdev_major;
1281         }
1282
1283         fw_core_add_address_handler(&topology_map, &topology_map_region);
1284         fw_core_add_address_handler(&registers, &registers_region);
1285         fw_core_add_address_handler(&low_memory, &low_memory_region);
1286         fw_core_add_descriptor(&vendor_id_descriptor);
1287         fw_core_add_descriptor(&model_id_descriptor);
1288
1289         return 0;
1290 }
1291
1292 static void __exit fw_core_cleanup(void)
1293 {
1294         unregister_chrdev(fw_cdev_major, "firewire");
1295         bus_unregister(&fw_bus_type);
1296         destroy_workqueue(fw_workqueue);
1297         idr_destroy(&fw_device_idr);
1298 }
1299
1300 module_init(fw_core_init);
1301 module_exit(fw_core_cleanup);