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
  40 #include <asm/byteorder.h>
  41
  42 #include "core.h"
  43
  44 #define HEADER_PRI(pri)                 ((pri) << 0)
  45 #define HEADER_TCODE(tcode)             ((tcode) << 4)
  46 #define HEADER_RETRY(retry)             ((retry) << 8)
  47 #define HEADER_TLABEL(tlabel)           ((tlabel) << 10)
  48 #define HEADER_DESTINATION(destination) ((destination) << 16)
  49 #define HEADER_SOURCE(source)           ((source) << 16)
  50 #define HEADER_RCODE(rcode)             ((rcode) << 12)
  51 #define HEADER_OFFSET_HIGH(offset_high) ((offset_high) << 0)
  52 #define HEADER_DATA_LENGTH(length)      ((length) << 16)
  53 #define HEADER_EXTENDED_TCODE(tcode)    ((tcode) << 0)
  54
  55 #define HEADER_GET_TCODE(q)             (((q) >> 4) & 0x0f)
  56 #define HEADER_GET_TLABEL(q)            (((q) >> 10) & 0x3f)
  57 #define HEADER_GET_RCODE(q)             (((q) >> 12) & 0x0f)
  58 #define HEADER_GET_DESTINATION(q)       (((q) >> 16) & 0xffff)
  59 #define HEADER_GET_SOURCE(q)            (((q) >> 16) & 0xffff)
  60 #define HEADER_GET_OFFSET_HIGH(q)       (((q) >> 0) & 0xffff)
  61 #define HEADER_GET_DATA_LENGTH(q)       (((q) >> 16) & 0xffff)
  62 #define HEADER_GET_EXTENDED_TCODE(q)    (((q) >> 0) & 0xffff)
  63
  64 #define HEADER_DESTINATION_IS_BROADCAST(q) \
  65         (((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
  66
  67 #define PHY_PACKET_CONFIG       0x0
  68 #define PHY_PACKET_LINK_ON      0x1
  69 #define PHY_PACKET_SELF_ID      0x2
  70
  71 #define PHY_CONFIG_GAP_COUNT(gap_count) (((gap_count) << 16) | (1 << 22))
  72 #define PHY_CONFIG_ROOT_ID(node_id)     ((((node_id) & 0x3f) << 24) | (1 << 23))
  73 #define PHY_IDENTIFIER(id)              ((id) << 30)
  74
  75 static int close_transaction(struct fw_transaction *transaction,
  76                              struct fw_card *card, int rcode)
  77 {
  78         struct fw_transaction *t;
  79         unsigned long flags;
  80
  81         spin_lock_irqsave(&card->lock, flags);
  82         list_for_each_entry(t, &card->transaction_list, link) {
  83                 if (t == transaction) {
  84                         list_del(&t->link);
  85                         card->tlabel_mask &= ~(1ULL << t->tlabel);
  86                         break;
  87                 }
  88         }
  89         spin_unlock_irqrestore(&card->lock, flags);
  90
  91         if (&t->link != &card->transaction_list) {
  92                 t->callback(card, rcode, NULL, 0, t->callback_data);
  93                 return 0;
  94         }
  95
  96         return -ENOENT;
  97 }
  98
  99 /*
 100  * Only valid for transactions that are potentially pending (ie have
 101  * been sent).
 102  */
 103 int fw_cancel_transaction(struct fw_card *card,
 104                           struct fw_transaction *transaction)
 105 {
 106         /*
 107          * Cancel the packet transmission if it's still queued.  That
 108          * will call the packet transmission callback which cancels
 109          * the transaction.
 110          */
 111
 112         if (card->driver->cancel_packet(card, &transaction->packet) == 0)
 113                 return 0;
 114
 115         /*
 116          * If the request packet has already been sent, we need to see
 117          * if the transaction is still pending and remove it in that case.
 118          */
 119
 120         return close_transaction(transaction, card, RCODE_CANCELLED);
 121 }
 122 EXPORT_SYMBOL(fw_cancel_transaction);
 123
 124 static void transmit_complete_callback(struct fw_packet *packet,
 125                                        struct fw_card *card, int status)
 126 {
 127         struct fw_transaction *t =
 128             container_of(packet, struct fw_transaction, packet);
 129
 130         switch (status) {
 131         case ACK_COMPLETE:
 132                 close_transaction(t, card, RCODE_COMPLETE);
 133                 break;
 134         case ACK_PENDING:
 135                 t->timestamp = packet->timestamp;
 136                 break;
 137         case ACK_BUSY_X:
 138         case ACK_BUSY_A:
 139         case ACK_BUSY_B:
 140                 close_transaction(t, card, RCODE_BUSY);
 141                 break;
 142         case ACK_DATA_ERROR:
 143                 close_transaction(t, card, RCODE_DATA_ERROR);
 144                 break;
 145         case ACK_TYPE_ERROR:
 146                 close_transaction(t, card, RCODE_TYPE_ERROR);
 147                 break;
 148         default:
 149                 /*
 150                  * In this case the ack is really a juju specific
 151                  * rcode, so just forward that to the callback.
 152                  */
 153                 close_transaction(t, card, status);
 154                 break;
 155         }
 156 }
 157
 158 static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
 159                 int destination_id, int source_id, int generation, int speed,
 160                 unsigned long long offset, void *payload, size_t length)
 161 {
 162         int ext_tcode;
 163
 164         if (tcode == TCODE_STREAM_DATA) {
 165                 packet->header[0] =
 166                         HEADER_DATA_LENGTH(length) |
 167                         destination_id |
 168                         HEADER_TCODE(TCODE_STREAM_DATA);
 169                 packet->header_length = 4;
 170                 packet->payload = payload;
 171                 packet->payload_length = length;
 172
 173                 goto common;
 174         }
 175
 176         if (tcode > 0x10) {
 177                 ext_tcode = tcode & ~0x10;
 178                 tcode = TCODE_LOCK_REQUEST;
 179         } else
 180                 ext_tcode = 0;
 181
 182         packet->header[0] =
 183                 HEADER_RETRY(RETRY_X) |
 184                 HEADER_TLABEL(tlabel) |
 185                 HEADER_TCODE(tcode) |
 186                 HEADER_DESTINATION(destination_id);
 187         packet->header[1] =
 188                 HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
 189         packet->header[2] =
 190                 offset;
 191
 192         switch (tcode) {
 193         case TCODE_WRITE_QUADLET_REQUEST:
 194                 packet->header[3] = *(u32 *)payload;
 195                 packet->header_length = 16;
 196                 packet->payload_length = 0;
 197                 break;
 198
 199         case TCODE_LOCK_REQUEST:
 200         case TCODE_WRITE_BLOCK_REQUEST:
 201                 packet->header[3] =
 202                         HEADER_DATA_LENGTH(length) |
 203                         HEADER_EXTENDED_TCODE(ext_tcode);
 204                 packet->header_length = 16;
 205                 packet->payload = payload;
 206                 packet->payload_length = length;
 207                 break;
 208
 209         case TCODE_READ_QUADLET_REQUEST:
 210                 packet->header_length = 12;
 211                 packet->payload_length = 0;
 212                 break;
 213
 214         case TCODE_READ_BLOCK_REQUEST:
 215                 packet->header[3] =
 216                         HEADER_DATA_LENGTH(length) |
 217                         HEADER_EXTENDED_TCODE(ext_tcode);
 218                 packet->header_length = 16;
 219                 packet->payload_length = 0;
 220                 break;
 221         }
 222  common:
 223         packet->speed = speed;
 224         packet->generation = generation;
 225         packet->ack = 0;
 226         packet->payload_bus = 0;
 227 }
 228
 229 /**
 230  * This function provides low-level access to the IEEE1394 transaction
 231  * logic.  Most C programs would use either fw_read(), fw_write() or
 232  * fw_lock() instead - those function are convenience wrappers for
 233  * this function.  The fw_send_request() function is primarily
 234  * provided as a flexible, one-stop entry point for languages bindings
 235  * and protocol bindings.
 236  *
 237  * FIXME: Document this function further, in particular the possible
 238  * values for rcode in the callback.  In short, we map ACK_COMPLETE to
 239  * RCODE_COMPLETE, internal errors set errno and set rcode to
 240  * RCODE_SEND_ERROR (which is out of range for standard ieee1394
 241  * rcodes).  All other rcodes are forwarded unchanged.  For all
 242  * errors, payload is NULL, length is 0.
 243  *
 244  * Can not expect the callback to be called before the function
 245  * returns, though this does happen in some cases (ACK_COMPLETE and
 246  * errors).
 247  *
 248  * The payload is only used for write requests and must not be freed
 249  * until the callback has been called.
 250  *
 251  * @param card the card from which to send the request
 252  * @param tcode the tcode for this transaction.  Do not use
 253  *   TCODE_LOCK_REQUEST directly, instead use TCODE_LOCK_MASK_SWAP
 254  *   etc. to specify tcode and ext_tcode.
 255  * @param node_id the destination node ID (bus ID and PHY ID concatenated)
 256  * @param generation the generation for which node_id is valid
 257  * @param speed the speed to use for sending the request
 258  * @param offset the 48 bit offset on the destination node
 259  * @param payload the data payload for the request subaction
 260  * @param length the length in bytes of the data to read
 261  * @param callback function to be called when the transaction is completed
 262  * @param callback_data pointer to arbitrary data, which will be
 263  *   passed to the callback
 264  *
 265  * In case of asynchronous stream packets i.e. TCODE_STREAM_DATA, the caller
 266  * needs to synthesize @destination_id with fw_stream_packet_destination_id().
 267  */
 268 void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 269                      int destination_id, int generation, int speed,
 270                      unsigned long long offset, void *payload, size_t length,
 271                      fw_transaction_callback_t callback, void *callback_data)
 272 {
 273         unsigned long flags;
 274         int tlabel;
 275
 276         /*
 277          * Bump the flush timer up 100ms first of all so we
 278          * don't race with a flush timer callback.
 279          */
 280
 281         mod_timer(&card->flush_timer, jiffies + DIV_ROUND_UP(HZ, 10));
 282
 283         /*
 284          * Allocate tlabel from the bitmap and put the transaction on
 285          * the list while holding the card spinlock.
 286          */
 287
 288         spin_lock_irqsave(&card->lock, flags);
 289
 290         tlabel = card->current_tlabel;
 291         if (card->tlabel_mask & (1ULL << tlabel)) {
 292                 spin_unlock_irqrestore(&card->lock, flags);
 293                 callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
 294                 return;
 295         }
 296
 297         card->current_tlabel = (card->current_tlabel + 1) & 0x3f;
 298         card->tlabel_mask |= (1ULL << tlabel);
 299
 300         t->node_id = destination_id;
 301         t->tlabel = tlabel;
 302         t->callback = callback;
 303         t->callback_data = callback_data;
 304
 305         fw_fill_request(&t->packet, tcode, t->tlabel,
 306                         destination_id, card->node_id, generation,
 307                         speed, offset, payload, length);
 308         t->packet.callback = transmit_complete_callback;
 309
 310         list_add_tail(&t->link, &card->transaction_list);
 311
 312         spin_unlock_irqrestore(&card->lock, flags);
 313
 314         card->driver->send_request(card, &t->packet);
 315 }
 316 EXPORT_SYMBOL(fw_send_request);
 317
 318 struct transaction_callback_data {
 319         struct completion done;
 320         void *payload;
 321         int rcode;
 322 };
 323
 324 static void transaction_callback(struct fw_card *card, int rcode,
 325                                  void *payload, size_t length, void *data)
 326 {
 327         struct transaction_callback_data *d = data;
 328
 329         if (rcode == RCODE_COMPLETE)
 330                 memcpy(d->payload, payload, length);
 331         d->rcode = rcode;
 332         complete(&d->done);
 333 }
 334
 335 /**
 336  * fw_run_transaction - send request and sleep until transaction is completed
 337  *
 338  * Returns the RCODE.
 339  */
 340 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 341                        int generation, int speed, unsigned long long offset,
 342                        void *payload, size_t length)
 343 {
 344         struct transaction_callback_data d;
 345         struct fw_transaction t;
 346
 347         init_completion(&d.done);
 348         d.payload = payload;
 349         fw_send_request(card, &t, tcode, destination_id, generation, speed,
 350                         offset, payload, length, transaction_callback, &d);
 351         wait_for_completion(&d.done);
 352
 353         return d.rcode;
 354 }
 355 EXPORT_SYMBOL(fw_run_transaction);
 356
 357 static DEFINE_MUTEX(phy_config_mutex);
 358 static DECLARE_COMPLETION(phy_config_done);
 359
 360 static void transmit_phy_packet_callback(struct fw_packet *packet,
 361                                          struct fw_card *card, int status)
 362 {
 363         complete(&phy_config_done);
 364 }
 365
 366 static struct fw_packet phy_config_packet = {
 367         .header_length  = 8,
 368         .payload_length = 0,
 369         .speed          = SCODE_100,
 370         .callback       = transmit_phy_packet_callback,
 371 };
 372
 373 void fw_send_phy_config(struct fw_card *card,
 374                         int node_id, int generation, int gap_count)
 375 {
 376         long timeout = DIV_ROUND_UP(HZ, 10);
 377         u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG) |
 378                    PHY_CONFIG_ROOT_ID(node_id) |
 379                    PHY_CONFIG_GAP_COUNT(gap_count);
 380
 381         mutex_lock(&phy_config_mutex);
 382
 383         phy_config_packet.header[0] = data;
 384         phy_config_packet.header[1] = ~data;
 385         phy_config_packet.generation = generation;
 386         INIT_COMPLETION(phy_config_done);
 387
 388         card->driver->send_request(card, &phy_config_packet);
 389         wait_for_completion_timeout(&phy_config_done, timeout);
 390
 391         mutex_unlock(&phy_config_mutex);
 392 }
 393
 394 void fw_flush_transactions(struct fw_card *card)
 395 {
 396         struct fw_transaction *t, *next;
 397         struct list_head list;
 398         unsigned long flags;
 399
 400         INIT_LIST_HEAD(&list);
 401         spin_lock_irqsave(&card->lock, flags);
 402         list_splice_init(&card->transaction_list, &list);
 403         card->tlabel_mask = 0;
 404         spin_unlock_irqrestore(&card->lock, flags);
 405
 406         list_for_each_entry_safe(t, next, &list, link) {
 407                 card->driver->cancel_packet(card, &t->packet);
 408
 409                 /*
 410                  * At this point cancel_packet will never call the
 411                  * transaction callback, since we just took all the
 412                  * transactions out of the list.  So do it here.
 413                  */
 414                 t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
 415         }
 416 }
 417
 418 static struct fw_address_handler *lookup_overlapping_address_handler(
 419         struct list_head *list, unsigned long long offset, size_t length)
 420 {
 421         struct fw_address_handler *handler;
 422
 423         list_for_each_entry(handler, list, link) {
 424                 if (handler->offset < offset + length &&
 425                     offset < handler->offset + handler->length)
 426                         return handler;
 427         }
 428
 429         return NULL;
 430 }
 431
 432 static struct fw_address_handler *lookup_enclosing_address_handler(
 433         struct list_head *list, unsigned long long offset, size_t length)
 434 {
 435         struct fw_address_handler *handler;
 436
 437         list_for_each_entry(handler, list, link) {
 438                 if (handler->offset <= offset &&
 439                     offset + length <= handler->offset + handler->length)
 440                         return handler;
 441         }
 442
 443         return NULL;
 444 }
 445
 446 static DEFINE_SPINLOCK(address_handler_lock);
 447 static LIST_HEAD(address_handler_list);
 448
 449 const struct fw_address_region fw_high_memory_region =
 450         { .start = 0x000100000000ULL, .end = 0xffffe0000000ULL,  };
 451 EXPORT_SYMBOL(fw_high_memory_region);
 452
 453 #if 0
 454 const struct fw_address_region fw_low_memory_region =
 455         { .start = 0x000000000000ULL, .end = 0x000100000000ULL,  };
 456 const struct fw_address_region fw_private_region =
 457         { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 458 const struct fw_address_region fw_csr_region =
 459         { .start = CSR_REGISTER_BASE,
 460           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 461 const struct fw_address_region fw_unit_space_region =
 462         { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 463 #endif  /*  0  */
 464
 465 /**
 466  * fw_core_add_address_handler - register for incoming requests
 467  * @handler: callback
 468  * @region: region in the IEEE 1212 node space address range
 469  *
 470  * region->start, ->end, and handler->length have to be quadlet-aligned.
 471  *
 472  * When a request is received that falls within the specified address range,
 473  * the specified callback is invoked.  The parameters passed to the callback
 474  * give the details of the particular request.
 475  *
 476  * Return value:  0 on success, non-zero otherwise.
 477  * The start offset of the handler's address region is determined by
 478  * fw_core_add_address_handler() and is returned in handler->offset.
 479  */
 480 int fw_core_add_address_handler(struct fw_address_handler *handler,
 481                                 const struct fw_address_region *region)
 482 {
 483         struct fw_address_handler *other;
 484         unsigned long flags;
 485         int ret = -EBUSY;
 486
 487         if (region->start & 0xffff000000000003ULL ||
 488             region->end   & 0xffff000000000003ULL ||
 489             region->start >= region->end ||
 490             handler->length & 3 ||
 491             handler->length == 0)
 492                 return -EINVAL;
 493
 494         spin_lock_irqsave(&address_handler_lock, flags);
 495
 496         handler->offset = region->start;
 497         while (handler->offset + handler->length <= region->end) {
 498                 other =
 499                     lookup_overlapping_address_handler(&address_handler_list,
 500                                                        handler->offset,
 501                                                        handler->length);
 502                 if (other != NULL) {
 503                         handler->offset += other->length;
 504                 } else {
 505                         list_add_tail(&handler->link, &address_handler_list);
 506                         ret = 0;
 507                         break;
 508                 }
 509         }
 510
 511         spin_unlock_irqrestore(&address_handler_lock, flags);
 512
 513         return ret;
 514 }
 515 EXPORT_SYMBOL(fw_core_add_address_handler);
 516
 517 /**
 518  * fw_core_remove_address_handler - unregister an address handler
 519  */
 520 void fw_core_remove_address_handler(struct fw_address_handler *handler)
 521 {
 522         unsigned long flags;
 523
 524         spin_lock_irqsave(&address_handler_lock, flags);
 525         list_del(&handler->link);
 526         spin_unlock_irqrestore(&address_handler_lock, flags);
 527 }
 528 EXPORT_SYMBOL(fw_core_remove_address_handler);
 529
 530 struct fw_request {
 531         struct fw_packet response;
 532         u32 request_header[4];
 533         int ack;
 534         u32 length;
 535         u32 data[0];
 536 };
 537
 538 static void free_response_callback(struct fw_packet *packet,
 539                                    struct fw_card *card, int status)
 540 {
 541         struct fw_request *request;
 542
 543         request = container_of(packet, struct fw_request, response);
 544         kfree(request);
 545 }
 546
 547 void fw_fill_response(struct fw_packet *response, u32 *request_header,
 548                       int rcode, void *payload, size_t length)
 549 {
 550         int tcode, tlabel, extended_tcode, source, destination;
 551
 552         tcode          = HEADER_GET_TCODE(request_header[0]);
 553         tlabel         = HEADER_GET_TLABEL(request_header[0]);
 554         source         = HEADER_GET_DESTINATION(request_header[0]);
 555         destination    = HEADER_GET_SOURCE(request_header[1]);
 556         extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 557
 558         response->header[0] =
 559                 HEADER_RETRY(RETRY_1) |
 560                 HEADER_TLABEL(tlabel) |
 561                 HEADER_DESTINATION(destination);
 562         response->header[1] =
 563                 HEADER_SOURCE(source) |
 564                 HEADER_RCODE(rcode);
 565         response->header[2] = 0;
 566
 567         switch (tcode) {
 568         case TCODE_WRITE_QUADLET_REQUEST:
 569         case TCODE_WRITE_BLOCK_REQUEST:
 570                 response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 571                 response->header_length = 12;
 572                 response->payload_length = 0;
 573                 break;
 574
 575         case TCODE_READ_QUADLET_REQUEST:
 576                 response->header[0] |=
 577                         HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 578                 if (payload != NULL)
 579                         response->header[3] = *(u32 *)payload;
 580                 else
 581                         response->header[3] = 0;
 582                 response->header_length = 16;
 583                 response->payload_length = 0;
 584                 break;
 585
 586         case TCODE_READ_BLOCK_REQUEST:
 587         case TCODE_LOCK_REQUEST:
 588                 response->header[0] |= HEADER_TCODE(tcode + 2);
 589                 response->header[3] =
 590                         HEADER_DATA_LENGTH(length) |
 591                         HEADER_EXTENDED_TCODE(extended_tcode);
 592                 response->header_length = 16;
 593                 response->payload = payload;
 594                 response->payload_length = length;
 595                 break;
 596
 597         default:
 598                 BUG();
 599                 return;
 600         }
 601
 602         response->payload_bus = 0;
 603 }
 604 EXPORT_SYMBOL(fw_fill_response);
 605
 606 static struct fw_request *allocate_request(struct fw_packet *p)
 607 {
 608         struct fw_request *request;
 609         u32 *data, length;
 610         int request_tcode, t;
 611
 612         request_tcode = HEADER_GET_TCODE(p->header[0]);
 613         switch (request_tcode) {
 614         case TCODE_WRITE_QUADLET_REQUEST:
 615                 data = &p->header[3];
 616                 length = 4;
 617                 break;
 618
 619         case TCODE_WRITE_BLOCK_REQUEST:
 620         case TCODE_LOCK_REQUEST:
 621                 data = p->payload;
 622                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 623                 break;
 624
 625         case TCODE_READ_QUADLET_REQUEST:
 626                 data = NULL;
 627                 length = 4;
 628                 break;
 629
 630         case TCODE_READ_BLOCK_REQUEST:
 631                 data = NULL;
 632                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 633                 break;
 634
 635         default:
 636                 fw_error("ERROR - corrupt request received - %08x %08x %08x\n",
 637                          p->header[0], p->header[1], p->header[2]);
 638                 return NULL;
 639         }
 640
 641         request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 642         if (request == NULL)
 643                 return NULL;
 644
 645         t = (p->timestamp & 0x1fff) + 4000;
 646         if (t >= 8000)
 647                 t = (p->timestamp & ~0x1fff) + 0x2000 + t - 8000;
 648         else
 649                 t = (p->timestamp & ~0x1fff) + t;
 650
 651         request->response.speed = p->speed;
 652         request->response.timestamp = t;
 653         request->response.generation = p->generation;
 654         request->response.ack = 0;
 655         request->response.callback = free_response_callback;
 656         request->ack = p->ack;
 657         request->length = length;
 658         if (data)
 659                 memcpy(request->data, data, length);
 660
 661         memcpy(request->request_header, p->header, sizeof(p->header));
 662
 663         return request;
 664 }
 665
 666 void fw_send_response(struct fw_card *card,
 667                       struct fw_request *request, int rcode)
 668 {
 669         /* unified transaction or broadcast transaction: don't respond */
 670         if (request->ack != ACK_PENDING ||
 671             HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 672                 kfree(request);
 673                 return;
 674         }
 675
 676         if (rcode == RCODE_COMPLETE)
 677                 fw_fill_response(&request->response, request->request_header,
 678                                  rcode, request->data, request->length);
 679         else
 680                 fw_fill_response(&request->response, request->request_header,
 681                                  rcode, NULL, 0);
 682
 683         card->driver->send_response(card, &request->response);
 684 }
 685 EXPORT_SYMBOL(fw_send_response);
 686
 687 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
 688 {
 689         struct fw_address_handler *handler;
 690         struct fw_request *request;
 691         unsigned long long offset;
 692         unsigned long flags;
 693         int tcode, destination, source;
 694
 695         if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
 696                 return;
 697
 698         request = allocate_request(p);
 699         if (request == NULL) {
 700                 /* FIXME: send statically allocated busy packet. */
 701                 return;
 702         }
 703
 704         offset      =
 705                 ((unsigned long long)
 706                  HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) | p->header[2];
 707         tcode       = HEADER_GET_TCODE(p->header[0]);
 708         destination = HEADER_GET_DESTINATION(p->header[0]);
 709         source      = HEADER_GET_SOURCE(p->header[1]);
 710
 711         spin_lock_irqsave(&address_handler_lock, flags);
 712         handler = lookup_enclosing_address_handler(&address_handler_list,
 713                                                    offset, request->length);
 714         spin_unlock_irqrestore(&address_handler_lock, flags);
 715
 716         /*
 717          * FIXME: lookup the fw_node corresponding to the sender of
 718          * this request and pass that to the address handler instead
 719          * of the node ID.  We may also want to move the address
 720          * allocations to fw_node so we only do this callback if the
 721          * upper layers registered it for this node.
 722          */
 723
 724         if (handler == NULL)
 725                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 726         else
 727                 handler->address_callback(card, request,
 728                                           tcode, destination, source,
 729                                           p->generation, p->speed, offset,
 730                                           request->data, request->length,
 731                                           handler->callback_data);
 732 }
 733 EXPORT_SYMBOL(fw_core_handle_request);
 734
 735 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
 736 {
 737         struct fw_transaction *t;
 738         unsigned long flags;
 739         u32 *data;
 740         size_t data_length;
 741         int tcode, tlabel, destination, source, rcode;
 742
 743         tcode       = HEADER_GET_TCODE(p->header[0]);
 744         tlabel      = HEADER_GET_TLABEL(p->header[0]);
 745         destination = HEADER_GET_DESTINATION(p->header[0]);
 746         source      = HEADER_GET_SOURCE(p->header[1]);
 747         rcode       = HEADER_GET_RCODE(p->header[1]);
 748
 749         spin_lock_irqsave(&card->lock, flags);
 750         list_for_each_entry(t, &card->transaction_list, link) {
 751                 if (t->node_id == source && t->tlabel == tlabel) {
 752                         list_del(&t->link);
 753                         card->tlabel_mask &= ~(1 << t->tlabel);
 754                         break;
 755                 }
 756         }
 757         spin_unlock_irqrestore(&card->lock, flags);
 758
 759         if (&t->link == &card->transaction_list) {
 760                 fw_notify("Unsolicited response (source %x, tlabel %x)\n",
 761                           source, tlabel);
 762                 return;
 763         }
 764
 765         /*
 766          * FIXME: sanity check packet, is length correct, does tcodes
 767          * and addresses match.
 768          */
 769
 770         switch (tcode) {
 771         case TCODE_READ_QUADLET_RESPONSE:
 772                 data = (u32 *) &p->header[3];
 773                 data_length = 4;
 774                 break;
 775
 776         case TCODE_WRITE_RESPONSE:
 777                 data = NULL;
 778                 data_length = 0;
 779                 break;
 780
 781         case TCODE_READ_BLOCK_RESPONSE:
 782         case TCODE_LOCK_RESPONSE:
 783                 data = p->payload;
 784                 data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
 785                 break;
 786
 787         default:
 788                 /* Should never happen, this is just to shut up gcc. */
 789                 data = NULL;
 790                 data_length = 0;
 791                 break;
 792         }
 793
 794         /*
 795          * The response handler may be executed while the request handler
 796          * is still pending.  Cancel the request handler.
 797          */
 798         card->driver->cancel_packet(card, &t->packet);
 799
 800         t->callback(card, rcode, data, data_length, t->callback_data);
 801 }
 802 EXPORT_SYMBOL(fw_core_handle_response);
 803
 804 static const struct fw_address_region topology_map_region =
 805         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
 806           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
 807
 808 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
 809                 int tcode, int destination, int source, int generation,
 810                 int speed, unsigned long long offset,
 811                 void *payload, size_t length, void *callback_data)
 812 {
 813         int i, start, end;
 814         __be32 *map;
 815
 816         if (!TCODE_IS_READ_REQUEST(tcode)) {
 817                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 818                 return;
 819         }
 820
 821         if ((offset & 3) > 0 || (length & 3) > 0) {
 822                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 823                 return;
 824         }
 825
 826         start = (offset - topology_map_region.start) / 4;
 827         end = start + length / 4;
 828         map = payload;
 829
 830         for (i = 0; i < length / 4; i++)
 831                 map[i] = cpu_to_be32(card->topology_map[start + i]);
 832
 833         fw_send_response(card, request, RCODE_COMPLETE);
 834 }
 835
 836 static struct fw_address_handler topology_map = {
 837         .length                 = 0x200,
 838         .address_callback       = handle_topology_map,
 839 };
 840
 841 static const struct fw_address_region registers_region =
 842         { .start = CSR_REGISTER_BASE,
 843           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
 844
 845 static void handle_registers(struct fw_card *card, struct fw_request *request,
 846                 int tcode, int destination, int source, int generation,
 847                 int speed, unsigned long long offset,
 848                 void *payload, size_t length, void *callback_data)
 849 {
 850         int reg = offset & ~CSR_REGISTER_BASE;
 851         unsigned long long bus_time;
 852         __be32 *data = payload;
 853         int rcode = RCODE_COMPLETE;
 854
 855         switch (reg) {
 856         case CSR_CYCLE_TIME:
 857         case CSR_BUS_TIME:
 858                 if (!TCODE_IS_READ_REQUEST(tcode) || length != 4) {
 859                         rcode = RCODE_TYPE_ERROR;
 860                         break;
 861                 }
 862
 863                 bus_time = card->driver->get_bus_time(card);
 864                 if (reg == CSR_CYCLE_TIME)
 865                         *data = cpu_to_be32(bus_time);
 866                 else
 867                         *data = cpu_to_be32(bus_time >> 25);
 868                 break;
 869
 870         case CSR_BROADCAST_CHANNEL:
 871                 if (tcode == TCODE_READ_QUADLET_REQUEST)
 872                         *data = cpu_to_be32(card->broadcast_channel);
 873                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
 874                         card->broadcast_channel =
 875                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
 876                             BROADCAST_CHANNEL_INITIAL;
 877                 else
 878                         rcode = RCODE_TYPE_ERROR;
 879                 break;
 880
 881         case CSR_BUS_MANAGER_ID:
 882         case CSR_BANDWIDTH_AVAILABLE:
 883         case CSR_CHANNELS_AVAILABLE_HI:
 884         case CSR_CHANNELS_AVAILABLE_LO:
 885                 /*
 886                  * FIXME: these are handled by the OHCI hardware and
 887                  * the stack never sees these request. If we add
 888                  * support for a new type of controller that doesn't
 889                  * handle this in hardware we need to deal with these
 890                  * transactions.
 891                  */
 892                 BUG();
 893                 break;
 894
 895         case CSR_BUSY_TIMEOUT:
 896                 /* FIXME: Implement this. */
 897
 898         default:
 899                 rcode = RCODE_ADDRESS_ERROR;
 900                 break;
 901         }
 902
 903         fw_send_response(card, request, rcode);
 904 }
 905
 906 static struct fw_address_handler registers = {
 907         .length                 = 0x400,
 908         .address_callback       = handle_registers,
 909 };
 910
 911 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
 912 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
 913 MODULE_LICENSE("GPL");
 914
 915 static const u32 vendor_textual_descriptor[] = {
 916         /* textual descriptor leaf () */
 917         0x00060000,
 918         0x00000000,
 919         0x00000000,
 920         0x4c696e75,             /* L i n u */
 921         0x78204669,             /* x   F i */
 922         0x72657769,             /* r e w i */
 923         0x72650000,             /* r e     */
 924 };
 925
 926 static const u32 model_textual_descriptor[] = {
 927         /* model descriptor leaf () */
 928         0x00030000,
 929         0x00000000,
 930         0x00000000,
 931         0x4a756a75,             /* J u j u */
 932 };
 933
 934 static struct fw_descriptor vendor_id_descriptor = {
 935         .length = ARRAY_SIZE(vendor_textual_descriptor),
 936         .immediate = 0x03d00d1e,
 937         .key = 0x81000000,
 938         .data = vendor_textual_descriptor,
 939 };
 940
 941 static struct fw_descriptor model_id_descriptor = {
 942         .length = ARRAY_SIZE(model_textual_descriptor),
 943         .immediate = 0x17000001,
 944         .key = 0x81000000,
 945         .data = model_textual_descriptor,
 946 };
 947
 948 static int __init fw_core_init(void)
 949 {
 950         int ret;
 951
 952         ret = bus_register(&fw_bus_type);
 953         if (ret < 0)
 954                 return ret;
 955
 956         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
 957         if (fw_cdev_major < 0) {
 958                 bus_unregister(&fw_bus_type);
 959                 return fw_cdev_major;
 960         }
 961
 962         fw_core_add_address_handler(&topology_map, &topology_map_region);
 963         fw_core_add_address_handler(&registers, &registers_region);
 964         fw_core_add_descriptor(&vendor_id_descriptor);
 965         fw_core_add_descriptor(&model_id_descriptor);
 966
 967         return 0;
 968 }
 969
 970 static void __exit fw_core_cleanup(void)
 971 {
 972         unregister_chrdev(fw_cdev_major, "firewire");
 973         bus_unregister(&fw_bus_type);
 974         idr_destroy(&fw_device_idr);
 975 }
 976
 977 module_init(fw_core_init);
 978 module_exit(fw_core_cleanup);