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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_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  * Return value:  0 on success, non-zero otherwise.
560  *
561  * The start offset of the handler's address region is determined by
562  * fw_core_add_address_handler() and is returned in handler->offset.
563  *
564  * Address allocations are exclusive, except for the FCP registers.
565  */
566 int fw_core_add_address_handler(struct fw_address_handler *handler,
567                                 const struct fw_address_region *region)
568 {
569         struct fw_address_handler *other;
570         int ret = -EBUSY;
571
572         if (region->start & 0xffff000000000003ULL ||
573             region->start >= region->end ||
574             region->end   > 0x0001000000000000ULL ||
575             handler->length & 3 ||
576             handler->length == 0)
577                 return -EINVAL;
578
579         spin_lock_bh(&address_handler_lock);
580
581         handler->offset = region->start;
582         while (handler->offset + handler->length <= region->end) {
583                 if (is_in_fcp_region(handler->offset, handler->length))
584                         other = NULL;
585                 else
586                         other = lookup_overlapping_address_handler
587                                         (&address_handler_list,
588                                          handler->offset, handler->length);
589                 if (other != NULL) {
590                         handler->offset += other->length;
591                 } else {
592                         list_add_tail_rcu(&handler->link, &address_handler_list);
593                         ret = 0;
594                         break;
595                 }
596         }
597
598         spin_unlock_bh(&address_handler_lock);
599
600         return ret;
601 }
602 EXPORT_SYMBOL(fw_core_add_address_handler);
603
604 /**
605  * fw_core_remove_address_handler() - unregister an address handler
606  *
607  * When fw_core_remove_address_handler() returns, @handler->callback() is
608  * guaranteed to not run on any CPU anymore.
609  */
610 void fw_core_remove_address_handler(struct fw_address_handler *handler)
611 {
612         spin_lock_bh(&address_handler_lock);
613         list_del_rcu(&handler->link);
614         spin_unlock_bh(&address_handler_lock);
615         synchronize_rcu();
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 /**
827  * fw_get_request_speed() - returns speed at which the @request was received
828  */
829 int fw_get_request_speed(struct fw_request *request)
830 {
831         return request->response.speed;
832 }
833 EXPORT_SYMBOL(fw_get_request_speed);
834
835 static void handle_exclusive_region_request(struct fw_card *card,
836                                             struct fw_packet *p,
837                                             struct fw_request *request,
838                                             unsigned long long offset)
839 {
840         struct fw_address_handler *handler;
841         int tcode, destination, source;
842
843         destination = HEADER_GET_DESTINATION(p->header[0]);
844         source      = HEADER_GET_SOURCE(p->header[1]);
845         tcode       = HEADER_GET_TCODE(p->header[0]);
846         if (tcode == TCODE_LOCK_REQUEST)
847                 tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
848
849         rcu_read_lock();
850         handler = lookup_enclosing_address_handler(&address_handler_list,
851                                                    offset, request->length);
852         if (handler)
853                 handler->address_callback(card, request,
854                                           tcode, destination, source,
855                                           p->generation, offset,
856                                           request->data, request->length,
857                                           handler->callback_data);
858         rcu_read_unlock();
859
860         if (!handler)
861                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
862 }
863
864 static void handle_fcp_region_request(struct fw_card *card,
865                                       struct fw_packet *p,
866                                       struct fw_request *request,
867                                       unsigned long long offset)
868 {
869         struct fw_address_handler *handler;
870         int tcode, destination, source;
871
872         if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
873              offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
874             request->length > 0x200) {
875                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
876
877                 return;
878         }
879
880         tcode       = HEADER_GET_TCODE(p->header[0]);
881         destination = HEADER_GET_DESTINATION(p->header[0]);
882         source      = HEADER_GET_SOURCE(p->header[1]);
883
884         if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
885             tcode != TCODE_WRITE_BLOCK_REQUEST) {
886                 fw_send_response(card, request, RCODE_TYPE_ERROR);
887
888                 return;
889         }
890
891         rcu_read_lock();
892         list_for_each_entry_rcu(handler, &address_handler_list, link) {
893                 if (is_enclosing_handler(handler, offset, request->length))
894                         handler->address_callback(card, NULL, tcode,
895                                                   destination, source,
896                                                   p->generation, offset,
897                                                   request->data,
898                                                   request->length,
899                                                   handler->callback_data);
900         }
901         rcu_read_unlock();
902
903         fw_send_response(card, request, RCODE_COMPLETE);
904 }
905
906 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
907 {
908         struct fw_request *request;
909         unsigned long long offset;
910
911         if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
912                 return;
913
914         if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
915                 fw_cdev_handle_phy_packet(card, p);
916                 return;
917         }
918
919         request = allocate_request(card, p);
920         if (request == NULL) {
921                 /* FIXME: send statically allocated busy packet. */
922                 return;
923         }
924
925         offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
926                 p->header[2];
927
928         if (!is_in_fcp_region(offset, request->length))
929                 handle_exclusive_region_request(card, p, request, offset);
930         else
931                 handle_fcp_region_request(card, p, request, offset);
932
933 }
934 EXPORT_SYMBOL(fw_core_handle_request);
935
936 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
937 {
938         struct fw_transaction *t;
939         unsigned long flags;
940         u32 *data;
941         size_t data_length;
942         int tcode, tlabel, source, rcode;
943
944         tcode   = HEADER_GET_TCODE(p->header[0]);
945         tlabel  = HEADER_GET_TLABEL(p->header[0]);
946         source  = HEADER_GET_SOURCE(p->header[1]);
947         rcode   = HEADER_GET_RCODE(p->header[1]);
948
949         spin_lock_irqsave(&card->lock, flags);
950         list_for_each_entry(t, &card->transaction_list, link) {
951                 if (t->node_id == source && t->tlabel == tlabel) {
952                         if (!try_cancel_split_timeout(t)) {
953                                 spin_unlock_irqrestore(&card->lock, flags);
954                                 goto timed_out;
955                         }
956                         list_del_init(&t->link);
957                         card->tlabel_mask &= ~(1ULL << t->tlabel);
958                         break;
959                 }
960         }
961         spin_unlock_irqrestore(&card->lock, flags);
962
963         if (&t->link == &card->transaction_list) {
964  timed_out:
965                 fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
966                           source, tlabel);
967                 return;
968         }
969
970         /*
971          * FIXME: sanity check packet, is length correct, does tcodes
972          * and addresses match.
973          */
974
975         switch (tcode) {
976         case TCODE_READ_QUADLET_RESPONSE:
977                 data = (u32 *) &p->header[3];
978                 data_length = 4;
979                 break;
980
981         case TCODE_WRITE_RESPONSE:
982                 data = NULL;
983                 data_length = 0;
984                 break;
985
986         case TCODE_READ_BLOCK_RESPONSE:
987         case TCODE_LOCK_RESPONSE:
988                 data = p->payload;
989                 data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
990                 break;
991
992         default:
993                 /* Should never happen, this is just to shut up gcc. */
994                 data = NULL;
995                 data_length = 0;
996                 break;
997         }
998
999         /*
1000          * The response handler may be executed while the request handler
1001          * is still pending.  Cancel the request handler.
1002          */
1003         card->driver->cancel_packet(card, &t->packet);
1004
1005         t->callback(card, rcode, data, data_length, t->callback_data);
1006 }
1007 EXPORT_SYMBOL(fw_core_handle_response);
1008
1009 /**
1010  * fw_rcode_string - convert a firewire result code to an error description
1011  * @rcode: the result code
1012  */
1013 const char *fw_rcode_string(int rcode)
1014 {
1015         static const char *const names[] = {
1016                 [RCODE_COMPLETE]       = "no error",
1017                 [RCODE_CONFLICT_ERROR] = "conflict error",
1018                 [RCODE_DATA_ERROR]     = "data error",
1019                 [RCODE_TYPE_ERROR]     = "type error",
1020                 [RCODE_ADDRESS_ERROR]  = "address error",
1021                 [RCODE_SEND_ERROR]     = "send error",
1022                 [RCODE_CANCELLED]      = "timeout",
1023                 [RCODE_BUSY]           = "busy",
1024                 [RCODE_GENERATION]     = "bus reset",
1025                 [RCODE_NO_ACK]         = "no ack",
1026         };
1027
1028         if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1029                 return names[rcode];
1030         else
1031                 return "unknown";
1032 }
1033 EXPORT_SYMBOL(fw_rcode_string);
1034
1035 static const struct fw_address_region topology_map_region =
1036         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1037           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1038
1039 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1040                 int tcode, int destination, int source, int generation,
1041                 unsigned long long offset, void *payload, size_t length,
1042                 void *callback_data)
1043 {
1044         int start;
1045
1046         if (!TCODE_IS_READ_REQUEST(tcode)) {
1047                 fw_send_response(card, request, RCODE_TYPE_ERROR);
1048                 return;
1049         }
1050
1051         if ((offset & 3) > 0 || (length & 3) > 0) {
1052                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1053                 return;
1054         }
1055
1056         start = (offset - topology_map_region.start) / 4;
1057         memcpy(payload, &card->topology_map[start], length);
1058
1059         fw_send_response(card, request, RCODE_COMPLETE);
1060 }
1061
1062 static struct fw_address_handler topology_map = {
1063         .length                 = 0x400,
1064         .address_callback       = handle_topology_map,
1065 };
1066
1067 static const struct fw_address_region registers_region =
1068         { .start = CSR_REGISTER_BASE,
1069           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1070
1071 static void update_split_timeout(struct fw_card *card)
1072 {
1073         unsigned int cycles;
1074
1075         cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1076
1077         /* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1078         cycles = clamp(cycles, 800u, 3u * 8000u);
1079
1080         card->split_timeout_cycles = cycles;
1081         card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1082 }
1083
1084 static void handle_registers(struct fw_card *card, struct fw_request *request,
1085                 int tcode, int destination, int source, int generation,
1086                 unsigned long long offset, void *payload, size_t length,
1087                 void *callback_data)
1088 {
1089         int reg = offset & ~CSR_REGISTER_BASE;
1090         __be32 *data = payload;
1091         int rcode = RCODE_COMPLETE;
1092         unsigned long flags;
1093
1094         switch (reg) {
1095         case CSR_PRIORITY_BUDGET:
1096                 if (!card->priority_budget_implemented) {
1097                         rcode = RCODE_ADDRESS_ERROR;
1098                         break;
1099                 }
1100                 /* else fall through */
1101
1102         case CSR_NODE_IDS:
1103                 /*
1104                  * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1105                  * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1106                  */
1107                 /* fall through */
1108
1109         case CSR_STATE_CLEAR:
1110         case CSR_STATE_SET:
1111         case CSR_CYCLE_TIME:
1112         case CSR_BUS_TIME:
1113         case CSR_BUSY_TIMEOUT:
1114                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1115                         *data = cpu_to_be32(card->driver->read_csr(card, reg));
1116                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1117                         card->driver->write_csr(card, reg, be32_to_cpu(*data));
1118                 else
1119                         rcode = RCODE_TYPE_ERROR;
1120                 break;
1121
1122         case CSR_RESET_START:
1123                 if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1124                         card->driver->write_csr(card, CSR_STATE_CLEAR,
1125                                                 CSR_STATE_BIT_ABDICATE);
1126                 else
1127                         rcode = RCODE_TYPE_ERROR;
1128                 break;
1129
1130         case CSR_SPLIT_TIMEOUT_HI:
1131                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1132                         *data = cpu_to_be32(card->split_timeout_hi);
1133                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1134                         spin_lock_irqsave(&card->lock, flags);
1135                         card->split_timeout_hi = be32_to_cpu(*data) & 7;
1136                         update_split_timeout(card);
1137                         spin_unlock_irqrestore(&card->lock, flags);
1138                 } else {
1139                         rcode = RCODE_TYPE_ERROR;
1140                 }
1141                 break;
1142
1143         case CSR_SPLIT_TIMEOUT_LO:
1144                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1145                         *data = cpu_to_be32(card->split_timeout_lo);
1146                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1147                         spin_lock_irqsave(&card->lock, flags);
1148                         card->split_timeout_lo =
1149                                         be32_to_cpu(*data) & 0xfff80000;
1150                         update_split_timeout(card);
1151                         spin_unlock_irqrestore(&card->lock, flags);
1152                 } else {
1153                         rcode = RCODE_TYPE_ERROR;
1154                 }
1155                 break;
1156
1157         case CSR_MAINT_UTILITY:
1158                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1159                         *data = card->maint_utility_register;
1160                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1161                         card->maint_utility_register = *data;
1162                 else
1163                         rcode = RCODE_TYPE_ERROR;
1164                 break;
1165
1166         case CSR_BROADCAST_CHANNEL:
1167                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1168                         *data = cpu_to_be32(card->broadcast_channel);
1169                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1170                         card->broadcast_channel =
1171                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1172                             BROADCAST_CHANNEL_INITIAL;
1173                 else
1174                         rcode = RCODE_TYPE_ERROR;
1175                 break;
1176
1177         case CSR_BUS_MANAGER_ID:
1178         case CSR_BANDWIDTH_AVAILABLE:
1179         case CSR_CHANNELS_AVAILABLE_HI:
1180         case CSR_CHANNELS_AVAILABLE_LO:
1181                 /*
1182                  * FIXME: these are handled by the OHCI hardware and
1183                  * the stack never sees these request. If we add
1184                  * support for a new type of controller that doesn't
1185                  * handle this in hardware we need to deal with these
1186                  * transactions.
1187                  */
1188                 BUG();
1189                 break;
1190
1191         default:
1192                 rcode = RCODE_ADDRESS_ERROR;
1193                 break;
1194         }
1195
1196         fw_send_response(card, request, rcode);
1197 }
1198
1199 static struct fw_address_handler registers = {
1200         .length                 = 0x400,
1201         .address_callback       = handle_registers,
1202 };
1203
1204 static void handle_low_memory(struct fw_card *card, struct fw_request *request,
1205                 int tcode, int destination, int source, int generation,
1206                 unsigned long long offset, void *payload, size_t length,
1207                 void *callback_data)
1208 {
1209         /*
1210          * This catches requests not handled by the physical DMA unit,
1211          * i.e., wrong transaction types or unauthorized source nodes.
1212          */
1213         fw_send_response(card, request, RCODE_TYPE_ERROR);
1214 }
1215
1216 static struct fw_address_handler low_memory = {
1217         .length                 = 0x000100000000ULL,
1218         .address_callback       = handle_low_memory,
1219 };
1220
1221 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1222 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1223 MODULE_LICENSE("GPL");
1224
1225 static const u32 vendor_textual_descriptor[] = {
1226         /* textual descriptor leaf () */
1227         0x00060000,
1228         0x00000000,
1229         0x00000000,
1230         0x4c696e75,             /* L i n u */
1231         0x78204669,             /* x   F i */
1232         0x72657769,             /* r e w i */
1233         0x72650000,             /* r e     */
1234 };
1235
1236 static const u32 model_textual_descriptor[] = {
1237         /* model descriptor leaf () */
1238         0x00030000,
1239         0x00000000,
1240         0x00000000,
1241         0x4a756a75,             /* J u j u */
1242 };
1243
1244 static struct fw_descriptor vendor_id_descriptor = {
1245         .length = ARRAY_SIZE(vendor_textual_descriptor),
1246         .immediate = 0x03d00d1e,
1247         .key = 0x81000000,
1248         .data = vendor_textual_descriptor,
1249 };
1250
1251 static struct fw_descriptor model_id_descriptor = {
1252         .length = ARRAY_SIZE(model_textual_descriptor),
1253         .immediate = 0x17000001,
1254         .key = 0x81000000,
1255         .data = model_textual_descriptor,
1256 };
1257
1258 static int __init fw_core_init(void)
1259 {
1260         int ret;
1261
1262         fw_workqueue = alloc_workqueue("firewire",
1263                                        WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0);
1264         if (!fw_workqueue)
1265                 return -ENOMEM;
1266
1267         ret = bus_register(&fw_bus_type);
1268         if (ret < 0) {
1269                 destroy_workqueue(fw_workqueue);
1270                 return ret;
1271         }
1272
1273         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1274         if (fw_cdev_major < 0) {
1275                 bus_unregister(&fw_bus_type);
1276                 destroy_workqueue(fw_workqueue);
1277                 return fw_cdev_major;
1278         }
1279
1280         fw_core_add_address_handler(&topology_map, &topology_map_region);
1281         fw_core_add_address_handler(&registers, &registers_region);
1282         fw_core_add_address_handler(&low_memory, &low_memory_region);
1283         fw_core_add_descriptor(&vendor_id_descriptor);
1284         fw_core_add_descriptor(&model_id_descriptor);
1285
1286         return 0;
1287 }
1288
1289 static void __exit fw_core_cleanup(void)
1290 {
1291         unregister_chrdev(fw_cdev_major, "firewire");
1292         bus_unregister(&fw_bus_type);
1293         destroy_workqueue(fw_workqueue);
1294         idr_destroy(&fw_device_idr);
1295 }
1296
1297 module_init(fw_core_init);
1298 module_exit(fw_core_cleanup);