190bf61533a27a21187d70b2bd84c0d7c4ff11e8
[cascardo/linux.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/slab.h>
35 #include <linux/spinlock.h>
36 #include <linux/string.h>
37 #include <linux/timer.h>
38 #include <linux/types.h>
39 #include <linux/workqueue.h>
40
41 #include <asm/byteorder.h>
42
43 #include "core.h"
44
45 #define HEADER_PRI(pri)                 ((pri) << 0)
46 #define HEADER_TCODE(tcode)             ((tcode) << 4)
47 #define HEADER_RETRY(retry)             ((retry) << 8)
48 #define HEADER_TLABEL(tlabel)           ((tlabel) << 10)
49 #define HEADER_DESTINATION(destination) ((destination) << 16)
50 #define HEADER_SOURCE(source)           ((source) << 16)
51 #define HEADER_RCODE(rcode)             ((rcode) << 12)
52 #define HEADER_OFFSET_HIGH(offset_high) ((offset_high) << 0)
53 #define HEADER_DATA_LENGTH(length)      ((length) << 16)
54 #define HEADER_EXTENDED_TCODE(tcode)    ((tcode) << 0)
55
56 #define HEADER_GET_TCODE(q)             (((q) >> 4) & 0x0f)
57 #define HEADER_GET_TLABEL(q)            (((q) >> 10) & 0x3f)
58 #define HEADER_GET_RCODE(q)             (((q) >> 12) & 0x0f)
59 #define HEADER_GET_DESTINATION(q)       (((q) >> 16) & 0xffff)
60 #define HEADER_GET_SOURCE(q)            (((q) >> 16) & 0xffff)
61 #define HEADER_GET_OFFSET_HIGH(q)       (((q) >> 0) & 0xffff)
62 #define HEADER_GET_DATA_LENGTH(q)       (((q) >> 16) & 0xffff)
63 #define HEADER_GET_EXTENDED_TCODE(q)    (((q) >> 0) & 0xffff)
64
65 #define HEADER_DESTINATION_IS_BROADCAST(q) \
66         (((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
67
68 #define PHY_PACKET_CONFIG       0x0
69 #define PHY_PACKET_LINK_ON      0x1
70 #define PHY_PACKET_SELF_ID      0x2
71
72 #define PHY_CONFIG_GAP_COUNT(gap_count) (((gap_count) << 16) | (1 << 22))
73 #define PHY_CONFIG_ROOT_ID(node_id)     ((((node_id) & 0x3f) << 24) | (1 << 23))
74 #define PHY_IDENTIFIER(id)              ((id) << 30)
75
76 /* returns 0 if the split timeout handler is already running */
77 static int try_cancel_split_timeout(struct fw_transaction *t)
78 {
79         if (t->is_split_transaction)
80                 return del_timer(&t->split_timeout_timer);
81         else
82                 return 1;
83 }
84
85 static int close_transaction(struct fw_transaction *transaction,
86                              struct fw_card *card, int rcode)
87 {
88         struct fw_transaction *t;
89         unsigned long flags;
90
91         spin_lock_irqsave(&card->lock, flags);
92         list_for_each_entry(t, &card->transaction_list, link) {
93                 if (t == transaction) {
94                         if (!try_cancel_split_timeout(t)) {
95                                 spin_unlock_irqrestore(&card->lock, flags);
96                                 goto timed_out;
97                         }
98                         list_del_init(&t->link);
99                         card->tlabel_mask &= ~(1ULL << t->tlabel);
100                         break;
101                 }
102         }
103         spin_unlock_irqrestore(&card->lock, flags);
104
105         if (&t->link != &card->transaction_list) {
106                 t->callback(card, rcode, NULL, 0, t->callback_data);
107                 return 0;
108         }
109
110  timed_out:
111         return -ENOENT;
112 }
113
114 /*
115  * Only valid for transactions that are potentially pending (ie have
116  * been sent).
117  */
118 int fw_cancel_transaction(struct fw_card *card,
119                           struct fw_transaction *transaction)
120 {
121         /*
122          * Cancel the packet transmission if it's still queued.  That
123          * will call the packet transmission callback which cancels
124          * the transaction.
125          */
126
127         if (card->driver->cancel_packet(card, &transaction->packet) == 0)
128                 return 0;
129
130         /*
131          * If the request packet has already been sent, we need to see
132          * if the transaction is still pending and remove it in that case.
133          */
134
135         return close_transaction(transaction, card, RCODE_CANCELLED);
136 }
137 EXPORT_SYMBOL(fw_cancel_transaction);
138
139 static void split_transaction_timeout_callback(unsigned long data)
140 {
141         struct fw_transaction *t = (struct fw_transaction *)data;
142         struct fw_card *card = t->card;
143         unsigned long flags;
144
145         spin_lock_irqsave(&card->lock, flags);
146         if (list_empty(&t->link)) {
147                 spin_unlock_irqrestore(&card->lock, flags);
148                 return;
149         }
150         list_del(&t->link);
151         card->tlabel_mask &= ~(1ULL << t->tlabel);
152         spin_unlock_irqrestore(&card->lock, flags);
153
154         t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
155 }
156
157 static void start_split_transaction_timeout(struct fw_transaction *t,
158                                             struct fw_card *card)
159 {
160         unsigned long flags;
161
162         spin_lock_irqsave(&card->lock, flags);
163
164         if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
165                 spin_unlock_irqrestore(&card->lock, flags);
166                 return;
167         }
168
169         t->is_split_transaction = true;
170         mod_timer(&t->split_timeout_timer,
171                   jiffies + card->split_timeout_jiffies);
172
173         spin_unlock_irqrestore(&card->lock, flags);
174 }
175
176 static void transmit_complete_callback(struct fw_packet *packet,
177                                        struct fw_card *card, int status)
178 {
179         struct fw_transaction *t =
180             container_of(packet, struct fw_transaction, packet);
181
182         switch (status) {
183         case ACK_COMPLETE:
184                 close_transaction(t, card, RCODE_COMPLETE);
185                 break;
186         case ACK_PENDING:
187                 start_split_transaction_timeout(t, card);
188                 break;
189         case ACK_BUSY_X:
190         case ACK_BUSY_A:
191         case ACK_BUSY_B:
192                 close_transaction(t, card, RCODE_BUSY);
193                 break;
194         case ACK_DATA_ERROR:
195                 close_transaction(t, card, RCODE_DATA_ERROR);
196                 break;
197         case ACK_TYPE_ERROR:
198                 close_transaction(t, card, RCODE_TYPE_ERROR);
199                 break;
200         default:
201                 /*
202                  * In this case the ack is really a juju specific
203                  * rcode, so just forward that to the callback.
204                  */
205                 close_transaction(t, card, status);
206                 break;
207         }
208 }
209
210 static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
211                 int destination_id, int source_id, int generation, int speed,
212                 unsigned long long offset, void *payload, size_t length)
213 {
214         int ext_tcode;
215
216         if (tcode == TCODE_STREAM_DATA) {
217                 packet->header[0] =
218                         HEADER_DATA_LENGTH(length) |
219                         destination_id |
220                         HEADER_TCODE(TCODE_STREAM_DATA);
221                 packet->header_length = 4;
222                 packet->payload = payload;
223                 packet->payload_length = length;
224
225                 goto common;
226         }
227
228         if (tcode > 0x10) {
229                 ext_tcode = tcode & ~0x10;
230                 tcode = TCODE_LOCK_REQUEST;
231         } else
232                 ext_tcode = 0;
233
234         packet->header[0] =
235                 HEADER_RETRY(RETRY_X) |
236                 HEADER_TLABEL(tlabel) |
237                 HEADER_TCODE(tcode) |
238                 HEADER_DESTINATION(destination_id);
239         packet->header[1] =
240                 HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
241         packet->header[2] =
242                 offset;
243
244         switch (tcode) {
245         case TCODE_WRITE_QUADLET_REQUEST:
246                 packet->header[3] = *(u32 *)payload;
247                 packet->header_length = 16;
248                 packet->payload_length = 0;
249                 break;
250
251         case TCODE_LOCK_REQUEST:
252         case TCODE_WRITE_BLOCK_REQUEST:
253                 packet->header[3] =
254                         HEADER_DATA_LENGTH(length) |
255                         HEADER_EXTENDED_TCODE(ext_tcode);
256                 packet->header_length = 16;
257                 packet->payload = payload;
258                 packet->payload_length = length;
259                 break;
260
261         case TCODE_READ_QUADLET_REQUEST:
262                 packet->header_length = 12;
263                 packet->payload_length = 0;
264                 break;
265
266         case TCODE_READ_BLOCK_REQUEST:
267                 packet->header[3] =
268                         HEADER_DATA_LENGTH(length) |
269                         HEADER_EXTENDED_TCODE(ext_tcode);
270                 packet->header_length = 16;
271                 packet->payload_length = 0;
272                 break;
273
274         default:
275                 WARN(1, "wrong tcode %d\n", tcode);
276         }
277  common:
278         packet->speed = speed;
279         packet->generation = generation;
280         packet->ack = 0;
281         packet->payload_mapped = false;
282 }
283
284 static int allocate_tlabel(struct fw_card *card)
285 {
286         int tlabel;
287
288         tlabel = card->current_tlabel;
289         while (card->tlabel_mask & (1ULL << tlabel)) {
290                 tlabel = (tlabel + 1) & 0x3f;
291                 if (tlabel == card->current_tlabel)
292                         return -EBUSY;
293         }
294
295         card->current_tlabel = (tlabel + 1) & 0x3f;
296         card->tlabel_mask |= 1ULL << tlabel;
297
298         return tlabel;
299 }
300
301 /**
302  * fw_send_request() - submit a request packet for transmission
303  * @card:               interface to send the request at
304  * @t:                  transaction instance to which the request belongs
305  * @tcode:              transaction code
306  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
307  * @generation:         bus generation in which request and response are valid
308  * @speed:              transmission speed
309  * @offset:             48bit wide offset into destination's address space
310  * @payload:            data payload for the request subaction
311  * @length:             length of the payload, in bytes
312  * @callback:           function to be called when the transaction is completed
313  * @callback_data:      data to be passed to the transaction completion callback
314  *
315  * Submit a request packet into the asynchronous request transmission queue.
316  * Can be called from atomic context.  If you prefer a blocking API, use
317  * fw_run_transaction() in a context that can sleep.
318  *
319  * In case of lock requests, specify one of the firewire-core specific %TCODE_
320  * constants instead of %TCODE_LOCK_REQUEST in @tcode.
321  *
322  * Make sure that the value in @destination_id is not older than the one in
323  * @generation.  Otherwise the request is in danger to be sent to a wrong node.
324  *
325  * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
326  * needs to synthesize @destination_id with fw_stream_packet_destination_id().
327  * It will contain tag, channel, and sy data instead of a node ID then.
328  *
329  * The payload buffer at @data is going to be DMA-mapped except in case of
330  * @length <= 8 or of local (loopback) requests.  Hence make sure that the
331  * buffer complies with the restrictions of the streaming DMA mapping API.
332  * @payload must not be freed before the @callback is called.
333  *
334  * In case of request types without payload, @data is NULL and @length is 0.
335  *
336  * After the transaction is completed successfully or unsuccessfully, the
337  * @callback will be called.  Among its parameters is the response code which
338  * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
339  * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
340  * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
341  * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
342  * generation, or missing ACK respectively.
343  *
344  * Note some timing corner cases:  fw_send_request() may complete much earlier
345  * than when the request packet actually hits the wire.  On the other hand,
346  * transaction completion and hence execution of @callback may happen even
347  * before fw_send_request() returns.
348  */
349 void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
350                      int destination_id, int generation, int speed,
351                      unsigned long long offset, void *payload, size_t length,
352                      fw_transaction_callback_t callback, void *callback_data)
353 {
354         unsigned long flags;
355         int tlabel;
356
357         /*
358          * Allocate tlabel from the bitmap and put the transaction on
359          * the list while holding the card spinlock.
360          */
361
362         spin_lock_irqsave(&card->lock, flags);
363
364         tlabel = allocate_tlabel(card);
365         if (tlabel < 0) {
366                 spin_unlock_irqrestore(&card->lock, flags);
367                 callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
368                 return;
369         }
370
371         t->node_id = destination_id;
372         t->tlabel = tlabel;
373         t->card = card;
374         t->is_split_transaction = false;
375         setup_timer(&t->split_timeout_timer,
376                     split_transaction_timeout_callback, (unsigned long)t);
377         t->callback = callback;
378         t->callback_data = callback_data;
379
380         fw_fill_request(&t->packet, tcode, t->tlabel,
381                         destination_id, card->node_id, generation,
382                         speed, offset, payload, length);
383         t->packet.callback = transmit_complete_callback;
384
385         list_add_tail(&t->link, &card->transaction_list);
386
387         spin_unlock_irqrestore(&card->lock, flags);
388
389         card->driver->send_request(card, &t->packet);
390 }
391 EXPORT_SYMBOL(fw_send_request);
392
393 struct transaction_callback_data {
394         struct completion done;
395         void *payload;
396         int rcode;
397 };
398
399 static void transaction_callback(struct fw_card *card, int rcode,
400                                  void *payload, size_t length, void *data)
401 {
402         struct transaction_callback_data *d = data;
403
404         if (rcode == RCODE_COMPLETE)
405                 memcpy(d->payload, payload, length);
406         d->rcode = rcode;
407         complete(&d->done);
408 }
409
410 /**
411  * fw_run_transaction() - send request and sleep until transaction is completed
412  *
413  * Returns the RCODE.  See fw_send_request() for parameter documentation.
414  * Unlike fw_send_request(), @data points to the payload of the request or/and
415  * to the payload of the response.  DMA mapping restrictions apply to outbound
416  * request payloads of >= 8 bytes but not to inbound response payloads.
417  */
418 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
419                        int generation, int speed, unsigned long long offset,
420                        void *payload, size_t length)
421 {
422         struct transaction_callback_data d;
423         struct fw_transaction t;
424
425         init_timer_on_stack(&t.split_timeout_timer);
426         init_completion(&d.done);
427         d.payload = payload;
428         fw_send_request(card, &t, tcode, destination_id, generation, speed,
429                         offset, payload, length, transaction_callback, &d);
430         wait_for_completion(&d.done);
431         destroy_timer_on_stack(&t.split_timeout_timer);
432
433         return d.rcode;
434 }
435 EXPORT_SYMBOL(fw_run_transaction);
436
437 static DEFINE_MUTEX(phy_config_mutex);
438 static DECLARE_COMPLETION(phy_config_done);
439
440 static void transmit_phy_packet_callback(struct fw_packet *packet,
441                                          struct fw_card *card, int status)
442 {
443         complete(&phy_config_done);
444 }
445
446 static struct fw_packet phy_config_packet = {
447         .header_length  = 12,
448         .header[0]      = TCODE_LINK_INTERNAL << 4,
449         .payload_length = 0,
450         .speed          = SCODE_100,
451         .callback       = transmit_phy_packet_callback,
452 };
453
454 void fw_send_phy_config(struct fw_card *card,
455                         int node_id, int generation, int gap_count)
456 {
457         long timeout = DIV_ROUND_UP(HZ, 10);
458         u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
459
460         if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
461                 data |= PHY_CONFIG_ROOT_ID(node_id);
462
463         if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
464                 gap_count = card->driver->read_phy_reg(card, 1);
465                 if (gap_count < 0)
466                         return;
467
468                 gap_count &= 63;
469                 if (gap_count == 63)
470                         return;
471         }
472         data |= PHY_CONFIG_GAP_COUNT(gap_count);
473
474         mutex_lock(&phy_config_mutex);
475
476         phy_config_packet.header[1] = data;
477         phy_config_packet.header[2] = ~data;
478         phy_config_packet.generation = generation;
479         INIT_COMPLETION(phy_config_done);
480
481         card->driver->send_request(card, &phy_config_packet);
482         wait_for_completion_timeout(&phy_config_done, timeout);
483
484         mutex_unlock(&phy_config_mutex);
485 }
486
487 static struct fw_address_handler *lookup_overlapping_address_handler(
488         struct list_head *list, unsigned long long offset, size_t length)
489 {
490         struct fw_address_handler *handler;
491
492         list_for_each_entry(handler, list, link) {
493                 if (handler->offset < offset + length &&
494                     offset < handler->offset + handler->length)
495                         return handler;
496         }
497
498         return NULL;
499 }
500
501 static bool is_enclosing_handler(struct fw_address_handler *handler,
502                                  unsigned long long offset, size_t length)
503 {
504         return handler->offset <= offset &&
505                 offset + length <= handler->offset + handler->length;
506 }
507
508 static struct fw_address_handler *lookup_enclosing_address_handler(
509         struct list_head *list, unsigned long long offset, size_t length)
510 {
511         struct fw_address_handler *handler;
512
513         list_for_each_entry(handler, list, link) {
514                 if (is_enclosing_handler(handler, offset, length))
515                         return handler;
516         }
517
518         return NULL;
519 }
520
521 static DEFINE_SPINLOCK(address_handler_lock);
522 static LIST_HEAD(address_handler_list);
523
524 const struct fw_address_region fw_high_memory_region =
525         { .start = 0x000100000000ULL, .end = 0xffffe0000000ULL,  };
526 EXPORT_SYMBOL(fw_high_memory_region);
527
528 #if 0
529 const struct fw_address_region fw_low_memory_region =
530         { .start = 0x000000000000ULL, .end = 0x000100000000ULL,  };
531 const struct fw_address_region fw_private_region =
532         { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
533 const struct fw_address_region fw_csr_region =
534         { .start = CSR_REGISTER_BASE,
535           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
536 const struct fw_address_region fw_unit_space_region =
537         { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
538 #endif  /*  0  */
539
540 static bool is_in_fcp_region(u64 offset, size_t length)
541 {
542         return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
543                 offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
544 }
545
546 /**
547  * fw_core_add_address_handler() - register for incoming requests
548  * @handler:    callback
549  * @region:     region in the IEEE 1212 node space address range
550  *
551  * region->start, ->end, and handler->length have to be quadlet-aligned.
552  *
553  * When a request is received that falls within the specified address range,
554  * the specified callback is invoked.  The parameters passed to the callback
555  * give the details of the particular request.
556  *
557  * Return value:  0 on success, non-zero otherwise.
558  *
559  * The start offset of the handler's address region is determined by
560  * fw_core_add_address_handler() and is returned in handler->offset.
561  *
562  * Address allocations are exclusive, except for the FCP registers.
563  */
564 int fw_core_add_address_handler(struct fw_address_handler *handler,
565                                 const struct fw_address_region *region)
566 {
567         struct fw_address_handler *other;
568         unsigned long flags;
569         int ret = -EBUSY;
570
571         if (region->start & 0xffff000000000003ULL ||
572             region->start >= region->end ||
573             region->end   > 0x0001000000000000ULL ||
574             handler->length & 3 ||
575             handler->length == 0)
576                 return -EINVAL;
577
578         spin_lock_irqsave(&address_handler_lock, flags);
579
580         handler->offset = region->start;
581         while (handler->offset + handler->length <= region->end) {
582                 if (is_in_fcp_region(handler->offset, handler->length))
583                         other = NULL;
584                 else
585                         other = lookup_overlapping_address_handler
586                                         (&address_handler_list,
587                                          handler->offset, handler->length);
588                 if (other != NULL) {
589                         handler->offset += other->length;
590                 } else {
591                         list_add_tail(&handler->link, &address_handler_list);
592                         ret = 0;
593                         break;
594                 }
595         }
596
597         spin_unlock_irqrestore(&address_handler_lock, flags);
598
599         return ret;
600 }
601 EXPORT_SYMBOL(fw_core_add_address_handler);
602
603 /**
604  * fw_core_remove_address_handler() - unregister an address handler
605  *
606  * When fw_core_remove_address_handler() returns, @handler->callback() is
607  * guaranteed to not run on any CPU anymore.
608  */
609 void fw_core_remove_address_handler(struct fw_address_handler *handler)
610 {
611         unsigned long flags;
612
613         spin_lock_irqsave(&address_handler_lock, flags);
614         list_del(&handler->link);
615         spin_unlock_irqrestore(&address_handler_lock, flags);
616 }
617 EXPORT_SYMBOL(fw_core_remove_address_handler);
618
619 struct fw_request {
620         struct fw_packet response;
621         u32 request_header[4];
622         int ack;
623         u32 length;
624         u32 data[0];
625 };
626
627 static void free_response_callback(struct fw_packet *packet,
628                                    struct fw_card *card, int status)
629 {
630         struct fw_request *request;
631
632         request = container_of(packet, struct fw_request, response);
633         kfree(request);
634 }
635
636 int fw_get_response_length(struct fw_request *r)
637 {
638         int tcode, ext_tcode, data_length;
639
640         tcode = HEADER_GET_TCODE(r->request_header[0]);
641
642         switch (tcode) {
643         case TCODE_WRITE_QUADLET_REQUEST:
644         case TCODE_WRITE_BLOCK_REQUEST:
645                 return 0;
646
647         case TCODE_READ_QUADLET_REQUEST:
648                 return 4;
649
650         case TCODE_READ_BLOCK_REQUEST:
651                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
652                 return data_length;
653
654         case TCODE_LOCK_REQUEST:
655                 ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
656                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
657                 switch (ext_tcode) {
658                 case EXTCODE_FETCH_ADD:
659                 case EXTCODE_LITTLE_ADD:
660                         return data_length;
661                 default:
662                         return data_length / 2;
663                 }
664
665         default:
666                 WARN(1, "wrong tcode %d\n", tcode);
667                 return 0;
668         }
669 }
670
671 void fw_fill_response(struct fw_packet *response, u32 *request_header,
672                       int rcode, void *payload, size_t length)
673 {
674         int tcode, tlabel, extended_tcode, source, destination;
675
676         tcode          = HEADER_GET_TCODE(request_header[0]);
677         tlabel         = HEADER_GET_TLABEL(request_header[0]);
678         source         = HEADER_GET_DESTINATION(request_header[0]);
679         destination    = HEADER_GET_SOURCE(request_header[1]);
680         extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
681
682         response->header[0] =
683                 HEADER_RETRY(RETRY_1) |
684                 HEADER_TLABEL(tlabel) |
685                 HEADER_DESTINATION(destination);
686         response->header[1] =
687                 HEADER_SOURCE(source) |
688                 HEADER_RCODE(rcode);
689         response->header[2] = 0;
690
691         switch (tcode) {
692         case TCODE_WRITE_QUADLET_REQUEST:
693         case TCODE_WRITE_BLOCK_REQUEST:
694                 response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
695                 response->header_length = 12;
696                 response->payload_length = 0;
697                 break;
698
699         case TCODE_READ_QUADLET_REQUEST:
700                 response->header[0] |=
701                         HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
702                 if (payload != NULL)
703                         response->header[3] = *(u32 *)payload;
704                 else
705                         response->header[3] = 0;
706                 response->header_length = 16;
707                 response->payload_length = 0;
708                 break;
709
710         case TCODE_READ_BLOCK_REQUEST:
711         case TCODE_LOCK_REQUEST:
712                 response->header[0] |= HEADER_TCODE(tcode + 2);
713                 response->header[3] =
714                         HEADER_DATA_LENGTH(length) |
715                         HEADER_EXTENDED_TCODE(extended_tcode);
716                 response->header_length = 16;
717                 response->payload = payload;
718                 response->payload_length = length;
719                 break;
720
721         default:
722                 WARN(1, "wrong tcode %d\n", tcode);
723         }
724
725         response->payload_mapped = false;
726 }
727 EXPORT_SYMBOL(fw_fill_response);
728
729 static u32 compute_split_timeout_timestamp(struct fw_card *card,
730                                            u32 request_timestamp)
731 {
732         unsigned int cycles;
733         u32 timestamp;
734
735         cycles = card->split_timeout_cycles;
736         cycles += request_timestamp & 0x1fff;
737
738         timestamp = request_timestamp & ~0x1fff;
739         timestamp += (cycles / 8000) << 13;
740         timestamp |= cycles % 8000;
741
742         return timestamp;
743 }
744
745 static struct fw_request *allocate_request(struct fw_card *card,
746                                            struct fw_packet *p)
747 {
748         struct fw_request *request;
749         u32 *data, length;
750         int request_tcode;
751
752         request_tcode = HEADER_GET_TCODE(p->header[0]);
753         switch (request_tcode) {
754         case TCODE_WRITE_QUADLET_REQUEST:
755                 data = &p->header[3];
756                 length = 4;
757                 break;
758
759         case TCODE_WRITE_BLOCK_REQUEST:
760         case TCODE_LOCK_REQUEST:
761                 data = p->payload;
762                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
763                 break;
764
765         case TCODE_READ_QUADLET_REQUEST:
766                 data = NULL;
767                 length = 4;
768                 break;
769
770         case TCODE_READ_BLOCK_REQUEST:
771                 data = NULL;
772                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
773                 break;
774
775         default:
776                 fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
777                          p->header[0], p->header[1], p->header[2]);
778                 return NULL;
779         }
780
781         request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
782         if (request == NULL)
783                 return NULL;
784
785         request->response.speed = p->speed;
786         request->response.timestamp =
787                         compute_split_timeout_timestamp(card, p->timestamp);
788         request->response.generation = p->generation;
789         request->response.ack = 0;
790         request->response.callback = free_response_callback;
791         request->ack = p->ack;
792         request->length = length;
793         if (data)
794                 memcpy(request->data, data, length);
795
796         memcpy(request->request_header, p->header, sizeof(p->header));
797
798         return request;
799 }
800
801 void fw_send_response(struct fw_card *card,
802                       struct fw_request *request, int rcode)
803 {
804         if (WARN_ONCE(!request, "invalid for FCP address handlers"))
805                 return;
806
807         /* unified transaction or broadcast transaction: don't respond */
808         if (request->ack != ACK_PENDING ||
809             HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
810                 kfree(request);
811                 return;
812         }
813
814         if (rcode == RCODE_COMPLETE)
815                 fw_fill_response(&request->response, request->request_header,
816                                  rcode, request->data,
817                                  fw_get_response_length(request));
818         else
819                 fw_fill_response(&request->response, request->request_header,
820                                  rcode, NULL, 0);
821
822         card->driver->send_response(card, &request->response);
823 }
824 EXPORT_SYMBOL(fw_send_response);
825
826 static void handle_exclusive_region_request(struct fw_card *card,
827                                             struct fw_packet *p,
828                                             struct fw_request *request,
829                                             unsigned long long offset)
830 {
831         struct fw_address_handler *handler;
832         unsigned long flags;
833         int tcode, destination, source;
834
835         destination = HEADER_GET_DESTINATION(p->header[0]);
836         source      = HEADER_GET_SOURCE(p->header[1]);
837         tcode       = HEADER_GET_TCODE(p->header[0]);
838         if (tcode == TCODE_LOCK_REQUEST)
839                 tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
840
841         spin_lock_irqsave(&address_handler_lock, flags);
842         handler = lookup_enclosing_address_handler(&address_handler_list,
843                                                    offset, request->length);
844         if (handler)
845                 handler->address_callback(card, request,
846                                           tcode, destination, source,
847                                           p->generation, offset,
848                                           request->data, request->length,
849                                           handler->callback_data);
850         spin_unlock_irqrestore(&address_handler_lock, flags);
851
852         if (!handler)
853                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
854 }
855
856 static void handle_fcp_region_request(struct fw_card *card,
857                                       struct fw_packet *p,
858                                       struct fw_request *request,
859                                       unsigned long long offset)
860 {
861         struct fw_address_handler *handler;
862         unsigned long flags;
863         int tcode, destination, source;
864
865         if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
866              offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
867             request->length > 0x200) {
868                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
869
870                 return;
871         }
872
873         tcode       = HEADER_GET_TCODE(p->header[0]);
874         destination = HEADER_GET_DESTINATION(p->header[0]);
875         source      = HEADER_GET_SOURCE(p->header[1]);
876
877         if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
878             tcode != TCODE_WRITE_BLOCK_REQUEST) {
879                 fw_send_response(card, request, RCODE_TYPE_ERROR);
880
881                 return;
882         }
883
884         spin_lock_irqsave(&address_handler_lock, flags);
885         list_for_each_entry(handler, &address_handler_list, link) {
886                 if (is_enclosing_handler(handler, offset, request->length))
887                         handler->address_callback(card, NULL, tcode,
888                                                   destination, source,
889                                                   p->generation, offset,
890                                                   request->data,
891                                                   request->length,
892                                                   handler->callback_data);
893         }
894         spin_unlock_irqrestore(&address_handler_lock, flags);
895
896         fw_send_response(card, request, RCODE_COMPLETE);
897 }
898
899 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
900 {
901         struct fw_request *request;
902         unsigned long long offset;
903
904         if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
905                 return;
906
907         if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
908                 fw_cdev_handle_phy_packet(card, p);
909                 return;
910         }
911
912         request = allocate_request(card, p);
913         if (request == NULL) {
914                 /* FIXME: send statically allocated busy packet. */
915                 return;
916         }
917
918         offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
919                 p->header[2];
920
921         if (!is_in_fcp_region(offset, request->length))
922                 handle_exclusive_region_request(card, p, request, offset);
923         else
924                 handle_fcp_region_request(card, p, request, offset);
925
926 }
927 EXPORT_SYMBOL(fw_core_handle_request);
928
929 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
930 {
931         struct fw_transaction *t;
932         unsigned long flags;
933         u32 *data;
934         size_t data_length;
935         int tcode, tlabel, source, rcode;
936
937         tcode   = HEADER_GET_TCODE(p->header[0]);
938         tlabel  = HEADER_GET_TLABEL(p->header[0]);
939         source  = HEADER_GET_SOURCE(p->header[1]);
940         rcode   = HEADER_GET_RCODE(p->header[1]);
941
942         spin_lock_irqsave(&card->lock, flags);
943         list_for_each_entry(t, &card->transaction_list, link) {
944                 if (t->node_id == source && t->tlabel == tlabel) {
945                         if (!try_cancel_split_timeout(t)) {
946                                 spin_unlock_irqrestore(&card->lock, flags);
947                                 goto timed_out;
948                         }
949                         list_del_init(&t->link);
950                         card->tlabel_mask &= ~(1ULL << t->tlabel);
951                         break;
952                 }
953         }
954         spin_unlock_irqrestore(&card->lock, flags);
955
956         if (&t->link == &card->transaction_list) {
957  timed_out:
958                 fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
959                           source, tlabel);
960                 return;
961         }
962
963         /*
964          * FIXME: sanity check packet, is length correct, does tcodes
965          * and addresses match.
966          */
967
968         switch (tcode) {
969         case TCODE_READ_QUADLET_RESPONSE:
970                 data = (u32 *) &p->header[3];
971                 data_length = 4;
972                 break;
973
974         case TCODE_WRITE_RESPONSE:
975                 data = NULL;
976                 data_length = 0;
977                 break;
978
979         case TCODE_READ_BLOCK_RESPONSE:
980         case TCODE_LOCK_RESPONSE:
981                 data = p->payload;
982                 data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
983                 break;
984
985         default:
986                 /* Should never happen, this is just to shut up gcc. */
987                 data = NULL;
988                 data_length = 0;
989                 break;
990         }
991
992         /*
993          * The response handler may be executed while the request handler
994          * is still pending.  Cancel the request handler.
995          */
996         card->driver->cancel_packet(card, &t->packet);
997
998         t->callback(card, rcode, data, data_length, t->callback_data);
999 }
1000 EXPORT_SYMBOL(fw_core_handle_response);
1001
1002 static const struct fw_address_region topology_map_region =
1003         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1004           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1005
1006 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1007                 int tcode, int destination, int source, int generation,
1008                 unsigned long long offset, void *payload, size_t length,
1009                 void *callback_data)
1010 {
1011         int start;
1012
1013         if (!TCODE_IS_READ_REQUEST(tcode)) {
1014                 fw_send_response(card, request, RCODE_TYPE_ERROR);
1015                 return;
1016         }
1017
1018         if ((offset & 3) > 0 || (length & 3) > 0) {
1019                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1020                 return;
1021         }
1022
1023         start = (offset - topology_map_region.start) / 4;
1024         memcpy(payload, &card->topology_map[start], length);
1025
1026         fw_send_response(card, request, RCODE_COMPLETE);
1027 }
1028
1029 static struct fw_address_handler topology_map = {
1030         .length                 = 0x400,
1031         .address_callback       = handle_topology_map,
1032 };
1033
1034 static const struct fw_address_region registers_region =
1035         { .start = CSR_REGISTER_BASE,
1036           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1037
1038 static void update_split_timeout(struct fw_card *card)
1039 {
1040         unsigned int cycles;
1041
1042         cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1043
1044         /* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1045         cycles = clamp(cycles, 800u, 3u * 8000u);
1046
1047         card->split_timeout_cycles = cycles;
1048         card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1049 }
1050
1051 static void handle_registers(struct fw_card *card, struct fw_request *request,
1052                 int tcode, int destination, int source, int generation,
1053                 unsigned long long offset, void *payload, size_t length,
1054                 void *callback_data)
1055 {
1056         int reg = offset & ~CSR_REGISTER_BASE;
1057         __be32 *data = payload;
1058         int rcode = RCODE_COMPLETE;
1059         unsigned long flags;
1060
1061         switch (reg) {
1062         case CSR_PRIORITY_BUDGET:
1063                 if (!card->priority_budget_implemented) {
1064                         rcode = RCODE_ADDRESS_ERROR;
1065                         break;
1066                 }
1067                 /* else fall through */
1068
1069         case CSR_NODE_IDS:
1070                 /*
1071                  * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1072                  * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1073                  */
1074                 /* fall through */
1075
1076         case CSR_STATE_CLEAR:
1077         case CSR_STATE_SET:
1078         case CSR_CYCLE_TIME:
1079         case CSR_BUS_TIME:
1080         case CSR_BUSY_TIMEOUT:
1081                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1082                         *data = cpu_to_be32(card->driver->read_csr(card, reg));
1083                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1084                         card->driver->write_csr(card, reg, be32_to_cpu(*data));
1085                 else
1086                         rcode = RCODE_TYPE_ERROR;
1087                 break;
1088
1089         case CSR_RESET_START:
1090                 if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1091                         card->driver->write_csr(card, CSR_STATE_CLEAR,
1092                                                 CSR_STATE_BIT_ABDICATE);
1093                 else
1094                         rcode = RCODE_TYPE_ERROR;
1095                 break;
1096
1097         case CSR_SPLIT_TIMEOUT_HI:
1098                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1099                         *data = cpu_to_be32(card->split_timeout_hi);
1100                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1101                         spin_lock_irqsave(&card->lock, flags);
1102                         card->split_timeout_hi = be32_to_cpu(*data) & 7;
1103                         update_split_timeout(card);
1104                         spin_unlock_irqrestore(&card->lock, flags);
1105                 } else {
1106                         rcode = RCODE_TYPE_ERROR;
1107                 }
1108                 break;
1109
1110         case CSR_SPLIT_TIMEOUT_LO:
1111                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1112                         *data = cpu_to_be32(card->split_timeout_lo);
1113                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1114                         spin_lock_irqsave(&card->lock, flags);
1115                         card->split_timeout_lo =
1116                                         be32_to_cpu(*data) & 0xfff80000;
1117                         update_split_timeout(card);
1118                         spin_unlock_irqrestore(&card->lock, flags);
1119                 } else {
1120                         rcode = RCODE_TYPE_ERROR;
1121                 }
1122                 break;
1123
1124         case CSR_MAINT_UTILITY:
1125                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1126                         *data = card->maint_utility_register;
1127                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1128                         card->maint_utility_register = *data;
1129                 else
1130                         rcode = RCODE_TYPE_ERROR;
1131                 break;
1132
1133         case CSR_BROADCAST_CHANNEL:
1134                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1135                         *data = cpu_to_be32(card->broadcast_channel);
1136                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1137                         card->broadcast_channel =
1138                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1139                             BROADCAST_CHANNEL_INITIAL;
1140                 else
1141                         rcode = RCODE_TYPE_ERROR;
1142                 break;
1143
1144         case CSR_BUS_MANAGER_ID:
1145         case CSR_BANDWIDTH_AVAILABLE:
1146         case CSR_CHANNELS_AVAILABLE_HI:
1147         case CSR_CHANNELS_AVAILABLE_LO:
1148                 /*
1149                  * FIXME: these are handled by the OHCI hardware and
1150                  * the stack never sees these request. If we add
1151                  * support for a new type of controller that doesn't
1152                  * handle this in hardware we need to deal with these
1153                  * transactions.
1154                  */
1155                 BUG();
1156                 break;
1157
1158         default:
1159                 rcode = RCODE_ADDRESS_ERROR;
1160                 break;
1161         }
1162
1163         fw_send_response(card, request, rcode);
1164 }
1165
1166 static struct fw_address_handler registers = {
1167         .length                 = 0x400,
1168         .address_callback       = handle_registers,
1169 };
1170
1171 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1172 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1173 MODULE_LICENSE("GPL");
1174
1175 static const u32 vendor_textual_descriptor[] = {
1176         /* textual descriptor leaf () */
1177         0x00060000,
1178         0x00000000,
1179         0x00000000,
1180         0x4c696e75,             /* L i n u */
1181         0x78204669,             /* x   F i */
1182         0x72657769,             /* r e w i */
1183         0x72650000,             /* r e     */
1184 };
1185
1186 static const u32 model_textual_descriptor[] = {
1187         /* model descriptor leaf () */
1188         0x00030000,
1189         0x00000000,
1190         0x00000000,
1191         0x4a756a75,             /* J u j u */
1192 };
1193
1194 static struct fw_descriptor vendor_id_descriptor = {
1195         .length = ARRAY_SIZE(vendor_textual_descriptor),
1196         .immediate = 0x03d00d1e,
1197         .key = 0x81000000,
1198         .data = vendor_textual_descriptor,
1199 };
1200
1201 static struct fw_descriptor model_id_descriptor = {
1202         .length = ARRAY_SIZE(model_textual_descriptor),
1203         .immediate = 0x17000001,
1204         .key = 0x81000000,
1205         .data = model_textual_descriptor,
1206 };
1207
1208 static int __init fw_core_init(void)
1209 {
1210         int ret;
1211
1212         fw_workqueue = alloc_workqueue("firewire",
1213                                        WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0);
1214         if (!fw_workqueue)
1215                 return -ENOMEM;
1216
1217         ret = bus_register(&fw_bus_type);
1218         if (ret < 0) {
1219                 destroy_workqueue(fw_workqueue);
1220                 return ret;
1221         }
1222
1223         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1224         if (fw_cdev_major < 0) {
1225                 bus_unregister(&fw_bus_type);
1226                 destroy_workqueue(fw_workqueue);
1227                 return fw_cdev_major;
1228         }
1229
1230         fw_core_add_address_handler(&topology_map, &topology_map_region);
1231         fw_core_add_address_handler(&registers, &registers_region);
1232         fw_core_add_descriptor(&vendor_id_descriptor);
1233         fw_core_add_descriptor(&model_id_descriptor);
1234
1235         return 0;
1236 }
1237
1238 static void __exit fw_core_cleanup(void)
1239 {
1240         unregister_chrdev(fw_cdev_major, "firewire");
1241         bus_unregister(&fw_bus_type);
1242         destroy_workqueue(fw_workqueue);
1243         idr_destroy(&fw_device_idr);
1244 }
1245
1246 module_init(fw_core_init);
1247 module_exit(fw_core_cleanup);