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