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