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