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  * @length <= 8 or of local (loopback) requests.  Hence make sure that the
 330  * buffer complies with the restrictions of the streaming DMA mapping API.
 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.  DMA mapping restrictions apply to outbound
 415  * request payloads of >= 8 bytes but not to inbound response payloads.
 416  */
 417 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 418                        int generation, int speed, unsigned long long offset,
 419                        void *payload, size_t length)
 420 {
 421         struct transaction_callback_data d;
 422         struct fw_transaction t;
 423
 424         init_timer_on_stack(&t.split_timeout_timer);
 425         init_completion(&d.done);
 426         d.payload = payload;
 427         fw_send_request(card, &t, tcode, destination_id, generation, speed,
 428                         offset, payload, length, transaction_callback, &d);
 429         wait_for_completion(&d.done);
 430         destroy_timer_on_stack(&t.split_timeout_timer);
 431
 432         return d.rcode;
 433 }
 434 EXPORT_SYMBOL(fw_run_transaction);
 435
 436 static DEFINE_MUTEX(phy_config_mutex);
 437 static DECLARE_COMPLETION(phy_config_done);
 438
 439 static void transmit_phy_packet_callback(struct fw_packet *packet,
 440                                          struct fw_card *card, int status)
 441 {
 442         complete(&phy_config_done);
 443 }
 444
 445 static struct fw_packet phy_config_packet = {
 446         .header_length  = 12,
 447         .header[0]      = TCODE_LINK_INTERNAL << 4,
 448         .payload_length = 0,
 449         .speed          = SCODE_100,
 450         .callback       = transmit_phy_packet_callback,
 451 };
 452
 453 void fw_send_phy_config(struct fw_card *card,
 454                         int node_id, int generation, int gap_count)
 455 {
 456         long timeout = DIV_ROUND_UP(HZ, 10);
 457         u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
 458
 459         if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
 460                 data |= PHY_CONFIG_ROOT_ID(node_id);
 461
 462         if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
 463                 gap_count = card->driver->read_phy_reg(card, 1);
 464                 if (gap_count < 0)
 465                         return;
 466
 467                 gap_count &= 63;
 468                 if (gap_count == 63)
 469                         return;
 470         }
 471         data |= PHY_CONFIG_GAP_COUNT(gap_count);
 472
 473         mutex_lock(&phy_config_mutex);
 474
 475         phy_config_packet.header[1] = data;
 476         phy_config_packet.header[2] = ~data;
 477         phy_config_packet.generation = generation;
 478         INIT_COMPLETION(phy_config_done);
 479
 480         card->driver->send_request(card, &phy_config_packet);
 481         wait_for_completion_timeout(&phy_config_done, timeout);
 482
 483         mutex_unlock(&phy_config_mutex);
 484 }
 485
 486 static struct fw_address_handler *lookup_overlapping_address_handler(
 487         struct list_head *list, unsigned long long offset, size_t length)
 488 {
 489         struct fw_address_handler *handler;
 490
 491         list_for_each_entry(handler, list, link) {
 492                 if (handler->offset < offset + length &&
 493                     offset < handler->offset + handler->length)
 494                         return handler;
 495         }
 496
 497         return NULL;
 498 }
 499
 500 static bool is_enclosing_handler(struct fw_address_handler *handler,
 501                                  unsigned long long offset, size_t length)
 502 {
 503         return handler->offset <= offset &&
 504                 offset + length <= handler->offset + handler->length;
 505 }
 506
 507 static struct fw_address_handler *lookup_enclosing_address_handler(
 508         struct list_head *list, unsigned long long offset, size_t length)
 509 {
 510         struct fw_address_handler *handler;
 511
 512         list_for_each_entry(handler, list, link) {
 513                 if (is_enclosing_handler(handler, offset, length))
 514                         return handler;
 515         }
 516
 517         return NULL;
 518 }
 519
 520 static DEFINE_SPINLOCK(address_handler_lock);
 521 static LIST_HEAD(address_handler_list);
 522
 523 const struct fw_address_region fw_high_memory_region =
 524         { .start = 0x000100000000ULL, .end = 0xffffe0000000ULL,  };
 525 EXPORT_SYMBOL(fw_high_memory_region);
 526
 527 #if 0
 528 const struct fw_address_region fw_low_memory_region =
 529         { .start = 0x000000000000ULL, .end = 0x000100000000ULL,  };
 530 const struct fw_address_region fw_private_region =
 531         { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 532 const struct fw_address_region fw_csr_region =
 533         { .start = CSR_REGISTER_BASE,
 534           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 535 const struct fw_address_region fw_unit_space_region =
 536         { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 537 #endif  /*  0  */
 538
 539 static bool is_in_fcp_region(u64 offset, size_t length)
 540 {
 541         return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 542                 offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
 543 }
 544
 545 /**
 546  * fw_core_add_address_handler() - register for incoming requests
 547  * @handler:    callback
 548  * @region:     region in the IEEE 1212 node space address range
 549  *
 550  * region->start, ->end, and handler->length have to be quadlet-aligned.
 551  *
 552  * When a request is received that falls within the specified address range,
 553  * the specified callback is invoked.  The parameters passed to the callback
 554  * give the details of the particular request.
 555  *
 556  * Return value:  0 on success, non-zero otherwise.
 557  *
 558  * The start offset of the handler's address region is determined by
 559  * fw_core_add_address_handler() and is returned in handler->offset.
 560  *
 561  * Address allocations are exclusive, except for the FCP registers.
 562  */
 563 int fw_core_add_address_handler(struct fw_address_handler *handler,
 564                                 const struct fw_address_region *region)
 565 {
 566         struct fw_address_handler *other;
 567         unsigned long flags;
 568         int ret = -EBUSY;
 569
 570         if (region->start & 0xffff000000000003ULL ||
 571             region->start >= region->end ||
 572             region->end   > 0x0001000000000000ULL ||
 573             handler->length & 3 ||
 574             handler->length == 0)
 575                 return -EINVAL;
 576
 577         spin_lock_irqsave(&address_handler_lock, flags);
 578
 579         handler->offset = region->start;
 580         while (handler->offset + handler->length <= region->end) {
 581                 if (is_in_fcp_region(handler->offset, handler->length))
 582                         other = NULL;
 583                 else
 584                         other = lookup_overlapping_address_handler
 585                                         (&address_handler_list,
 586                                          handler->offset, handler->length);
 587                 if (other != NULL) {
 588                         handler->offset += other->length;
 589                 } else {
 590                         list_add_tail(&handler->link, &address_handler_list);
 591                         ret = 0;
 592                         break;
 593                 }
 594         }
 595
 596         spin_unlock_irqrestore(&address_handler_lock, flags);
 597
 598         return ret;
 599 }
 600 EXPORT_SYMBOL(fw_core_add_address_handler);
 601
 602 /**
 603  * fw_core_remove_address_handler() - unregister an address handler
 604  */
 605 void fw_core_remove_address_handler(struct fw_address_handler *handler)
 606 {
 607         unsigned long flags;
 608
 609         spin_lock_irqsave(&address_handler_lock, flags);
 610         list_del(&handler->link);
 611         spin_unlock_irqrestore(&address_handler_lock, flags);
 612 }
 613 EXPORT_SYMBOL(fw_core_remove_address_handler);
 614
 615 struct fw_request {
 616         struct fw_packet response;
 617         u32 request_header[4];
 618         int ack;
 619         u32 length;
 620         u32 data[0];
 621 };
 622
 623 static void free_response_callback(struct fw_packet *packet,
 624                                    struct fw_card *card, int status)
 625 {
 626         struct fw_request *request;
 627
 628         request = container_of(packet, struct fw_request, response);
 629         kfree(request);
 630 }
 631
 632 int fw_get_response_length(struct fw_request *r)
 633 {
 634         int tcode, ext_tcode, data_length;
 635
 636         tcode = HEADER_GET_TCODE(r->request_header[0]);
 637
 638         switch (tcode) {
 639         case TCODE_WRITE_QUADLET_REQUEST:
 640         case TCODE_WRITE_BLOCK_REQUEST:
 641                 return 0;
 642
 643         case TCODE_READ_QUADLET_REQUEST:
 644                 return 4;
 645
 646         case TCODE_READ_BLOCK_REQUEST:
 647                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 648                 return data_length;
 649
 650         case TCODE_LOCK_REQUEST:
 651                 ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
 652                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 653                 switch (ext_tcode) {
 654                 case EXTCODE_FETCH_ADD:
 655                 case EXTCODE_LITTLE_ADD:
 656                         return data_length;
 657                 default:
 658                         return data_length / 2;
 659                 }
 660
 661         default:
 662                 WARN(1, "wrong tcode %d\n", tcode);
 663                 return 0;
 664         }
 665 }
 666
 667 void fw_fill_response(struct fw_packet *response, u32 *request_header,
 668                       int rcode, void *payload, size_t length)
 669 {
 670         int tcode, tlabel, extended_tcode, source, destination;
 671
 672         tcode          = HEADER_GET_TCODE(request_header[0]);
 673         tlabel         = HEADER_GET_TLABEL(request_header[0]);
 674         source         = HEADER_GET_DESTINATION(request_header[0]);
 675         destination    = HEADER_GET_SOURCE(request_header[1]);
 676         extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 677
 678         response->header[0] =
 679                 HEADER_RETRY(RETRY_1) |
 680                 HEADER_TLABEL(tlabel) |
 681                 HEADER_DESTINATION(destination);
 682         response->header[1] =
 683                 HEADER_SOURCE(source) |
 684                 HEADER_RCODE(rcode);
 685         response->header[2] = 0;
 686
 687         switch (tcode) {
 688         case TCODE_WRITE_QUADLET_REQUEST:
 689         case TCODE_WRITE_BLOCK_REQUEST:
 690                 response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 691                 response->header_length = 12;
 692                 response->payload_length = 0;
 693                 break;
 694
 695         case TCODE_READ_QUADLET_REQUEST:
 696                 response->header[0] |=
 697                         HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 698                 if (payload != NULL)
 699                         response->header[3] = *(u32 *)payload;
 700                 else
 701                         response->header[3] = 0;
 702                 response->header_length = 16;
 703                 response->payload_length = 0;
 704                 break;
 705
 706         case TCODE_READ_BLOCK_REQUEST:
 707         case TCODE_LOCK_REQUEST:
 708                 response->header[0] |= HEADER_TCODE(tcode + 2);
 709                 response->header[3] =
 710                         HEADER_DATA_LENGTH(length) |
 711                         HEADER_EXTENDED_TCODE(extended_tcode);
 712                 response->header_length = 16;
 713                 response->payload = payload;
 714                 response->payload_length = length;
 715                 break;
 716
 717         default:
 718                 WARN(1, "wrong tcode %d\n", tcode);
 719         }
 720
 721         response->payload_mapped = false;
 722 }
 723 EXPORT_SYMBOL(fw_fill_response);
 724
 725 static u32 compute_split_timeout_timestamp(struct fw_card *card,
 726                                            u32 request_timestamp)
 727 {
 728         unsigned int cycles;
 729         u32 timestamp;
 730
 731         cycles = card->split_timeout_cycles;
 732         cycles += request_timestamp & 0x1fff;
 733
 734         timestamp = request_timestamp & ~0x1fff;
 735         timestamp += (cycles / 8000) << 13;
 736         timestamp |= cycles % 8000;
 737
 738         return timestamp;
 739 }
 740
 741 static struct fw_request *allocate_request(struct fw_card *card,
 742                                            struct fw_packet *p)
 743 {
 744         struct fw_request *request;
 745         u32 *data, length;
 746         int request_tcode;
 747
 748         request_tcode = HEADER_GET_TCODE(p->header[0]);
 749         switch (request_tcode) {
 750         case TCODE_WRITE_QUADLET_REQUEST:
 751                 data = &p->header[3];
 752                 length = 4;
 753                 break;
 754
 755         case TCODE_WRITE_BLOCK_REQUEST:
 756         case TCODE_LOCK_REQUEST:
 757                 data = p->payload;
 758                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 759                 break;
 760
 761         case TCODE_READ_QUADLET_REQUEST:
 762                 data = NULL;
 763                 length = 4;
 764                 break;
 765
 766         case TCODE_READ_BLOCK_REQUEST:
 767                 data = NULL;
 768                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 769                 break;
 770
 771         default:
 772                 fw_error("ERROR - corrupt request received - %08x %08x %08x\n",
 773                          p->header[0], p->header[1], p->header[2]);
 774                 return NULL;
 775         }
 776
 777         request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 778         if (request == NULL)
 779                 return NULL;
 780
 781         request->response.speed = p->speed;
 782         request->response.timestamp =
 783                         compute_split_timeout_timestamp(card, p->timestamp);
 784         request->response.generation = p->generation;
 785         request->response.ack = 0;
 786         request->response.callback = free_response_callback;
 787         request->ack = p->ack;
 788         request->length = length;
 789         if (data)
 790                 memcpy(request->data, data, length);
 791
 792         memcpy(request->request_header, p->header, sizeof(p->header));
 793
 794         return request;
 795 }
 796
 797 void fw_send_response(struct fw_card *card,
 798                       struct fw_request *request, int rcode)
 799 {
 800         if (WARN_ONCE(!request, "invalid for FCP address handlers"))
 801                 return;
 802
 803         /* unified transaction or broadcast transaction: don't respond */
 804         if (request->ack != ACK_PENDING ||
 805             HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 806                 kfree(request);
 807                 return;
 808         }
 809
 810         if (rcode == RCODE_COMPLETE)
 811                 fw_fill_response(&request->response, request->request_header,
 812                                  rcode, request->data,
 813                                  fw_get_response_length(request));
 814         else
 815                 fw_fill_response(&request->response, request->request_header,
 816                                  rcode, NULL, 0);
 817
 818         card->driver->send_response(card, &request->response);
 819 }
 820 EXPORT_SYMBOL(fw_send_response);
 821
 822 static void handle_exclusive_region_request(struct fw_card *card,
 823                                             struct fw_packet *p,
 824                                             struct fw_request *request,
 825                                             unsigned long long offset)
 826 {
 827         struct fw_address_handler *handler;
 828         unsigned long flags;
 829         int tcode, destination, source;
 830
 831         destination = HEADER_GET_DESTINATION(p->header[0]);
 832         source      = HEADER_GET_SOURCE(p->header[1]);
 833         tcode       = HEADER_GET_TCODE(p->header[0]);
 834         if (tcode == TCODE_LOCK_REQUEST)
 835                 tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 836
 837         spin_lock_irqsave(&address_handler_lock, flags);
 838         handler = lookup_enclosing_address_handler(&address_handler_list,
 839                                                    offset, request->length);
 840         spin_unlock_irqrestore(&address_handler_lock, flags);
 841
 842         /*
 843          * FIXME: lookup the fw_node corresponding to the sender of
 844          * this request and pass that to the address handler instead
 845          * of the node ID.  We may also want to move the address
 846          * allocations to fw_node so we only do this callback if the
 847          * upper layers registered it for this node.
 848          */
 849
 850         if (handler == NULL)
 851                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 852         else
 853                 handler->address_callback(card, request,
 854                                           tcode, destination, source,
 855                                           p->generation, offset,
 856                                           request->data, request->length,
 857                                           handler->callback_data);
 858 }
 859
 860 static void handle_fcp_region_request(struct fw_card *card,
 861                                       struct fw_packet *p,
 862                                       struct fw_request *request,
 863                                       unsigned long long offset)
 864 {
 865         struct fw_address_handler *handler;
 866         unsigned long flags;
 867         int tcode, destination, source;
 868
 869         if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 870              offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
 871             request->length > 0x200) {
 872                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 873
 874                 return;
 875         }
 876
 877         tcode       = HEADER_GET_TCODE(p->header[0]);
 878         destination = HEADER_GET_DESTINATION(p->header[0]);
 879         source      = HEADER_GET_SOURCE(p->header[1]);
 880
 881         if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
 882             tcode != TCODE_WRITE_BLOCK_REQUEST) {
 883                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 884
 885                 return;
 886         }
 887
 888         spin_lock_irqsave(&address_handler_lock, flags);
 889         list_for_each_entry(handler, &address_handler_list, link) {
 890                 if (is_enclosing_handler(handler, offset, request->length))
 891                         handler->address_callback(card, NULL, tcode,
 892                                                   destination, source,
 893                                                   p->generation, offset,
 894                                                   request->data,
 895                                                   request->length,
 896                                                   handler->callback_data);
 897         }
 898         spin_unlock_irqrestore(&address_handler_lock, flags);
 899
 900         fw_send_response(card, request, RCODE_COMPLETE);
 901 }
 902
 903 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
 904 {
 905         struct fw_request *request;
 906         unsigned long long offset;
 907
 908         if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
 909                 return;
 910
 911         if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
 912                 fw_cdev_handle_phy_packet(card, p);
 913                 return;
 914         }
 915
 916         request = allocate_request(card, p);
 917         if (request == NULL) {
 918                 /* FIXME: send statically allocated busy packet. */
 919                 return;
 920         }
 921
 922         offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
 923                 p->header[2];
 924
 925         if (!is_in_fcp_region(offset, request->length))
 926                 handle_exclusive_region_request(card, p, request, offset);
 927         else
 928                 handle_fcp_region_request(card, p, request, offset);
 929
 930 }
 931 EXPORT_SYMBOL(fw_core_handle_request);
 932
 933 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
 934 {
 935         struct fw_transaction *t;
 936         unsigned long flags;
 937         u32 *data;
 938         size_t data_length;
 939         int tcode, tlabel, source, rcode;
 940
 941         tcode   = HEADER_GET_TCODE(p->header[0]);
 942         tlabel  = HEADER_GET_TLABEL(p->header[0]);
 943         source  = HEADER_GET_SOURCE(p->header[1]);
 944         rcode   = HEADER_GET_RCODE(p->header[1]);
 945
 946         spin_lock_irqsave(&card->lock, flags);
 947         list_for_each_entry(t, &card->transaction_list, link) {
 948                 if (t->node_id == source && t->tlabel == tlabel) {
 949                         if (!try_cancel_split_timeout(t)) {
 950                                 spin_unlock_irqrestore(&card->lock, flags);
 951                                 goto timed_out;
 952                         }
 953                         list_del_init(&t->link);
 954                         card->tlabel_mask &= ~(1ULL << t->tlabel);
 955                         break;
 956                 }
 957         }
 958         spin_unlock_irqrestore(&card->lock, flags);
 959
 960         if (&t->link == &card->transaction_list) {
 961  timed_out:
 962                 fw_notify("Unsolicited response (source %x, tlabel %x)\n",
 963                           source, tlabel);
 964                 return;
 965         }
 966
 967         /*
 968          * FIXME: sanity check packet, is length correct, does tcodes
 969          * and addresses match.
 970          */
 971
 972         switch (tcode) {
 973         case TCODE_READ_QUADLET_RESPONSE:
 974                 data = (u32 *) &p->header[3];
 975                 data_length = 4;
 976                 break;
 977
 978         case TCODE_WRITE_RESPONSE:
 979                 data = NULL;
 980                 data_length = 0;
 981                 break;
 982
 983         case TCODE_READ_BLOCK_RESPONSE:
 984         case TCODE_LOCK_RESPONSE:
 985                 data = p->payload;
 986                 data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
 987                 break;
 988
 989         default:
 990                 /* Should never happen, this is just to shut up gcc. */
 991                 data = NULL;
 992                 data_length = 0;
 993                 break;
 994         }
 995
 996         /*
 997          * The response handler may be executed while the request handler
 998          * is still pending.  Cancel the request handler.
 999          */
1000         card->driver->cancel_packet(card, &t->packet);
1001
1002         t->callback(card, rcode, data, data_length, t->callback_data);
1003 }
1004 EXPORT_SYMBOL(fw_core_handle_response);
1005
1006 static const struct fw_address_region topology_map_region =
1007         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1008           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1009
1010 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1011                 int tcode, int destination, int source, int generation,
1012                 unsigned long long offset, void *payload, size_t length,
1013                 void *callback_data)
1014 {
1015         int start;
1016
1017         if (!TCODE_IS_READ_REQUEST(tcode)) {
1018                 fw_send_response(card, request, RCODE_TYPE_ERROR);
1019                 return;
1020         }
1021
1022         if ((offset & 3) > 0 || (length & 3) > 0) {
1023                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1024                 return;
1025         }
1026
1027         start = (offset - topology_map_region.start) / 4;
1028         memcpy(payload, &card->topology_map[start], length);
1029
1030         fw_send_response(card, request, RCODE_COMPLETE);
1031 }
1032
1033 static struct fw_address_handler topology_map = {
1034         .length                 = 0x400,
1035         .address_callback       = handle_topology_map,
1036 };
1037
1038 static const struct fw_address_region registers_region =
1039         { .start = CSR_REGISTER_BASE,
1040           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1041
1042 static void update_split_timeout(struct fw_card *card)
1043 {
1044         unsigned int cycles;
1045
1046         cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1047
1048         cycles = max(cycles, 800u); /* minimum as per the spec */
1049         cycles = min(cycles, 3u * 8000u); /* maximum OHCI timeout */
1050
1051         card->split_timeout_cycles = cycles;
1052         card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1053 }
1054
1055 static void handle_registers(struct fw_card *card, struct fw_request *request,
1056                 int tcode, int destination, int source, int generation,
1057                 unsigned long long offset, void *payload, size_t length,
1058                 void *callback_data)
1059 {
1060         int reg = offset & ~CSR_REGISTER_BASE;
1061         __be32 *data = payload;
1062         int rcode = RCODE_COMPLETE;
1063         unsigned long flags;
1064
1065         switch (reg) {
1066         case CSR_PRIORITY_BUDGET:
1067                 if (!card->priority_budget_implemented) {
1068                         rcode = RCODE_ADDRESS_ERROR;
1069                         break;
1070                 }
1071                 /* else fall through */
1072
1073         case CSR_NODE_IDS:
1074                 /*
1075                  * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1076                  * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1077                  */
1078                 /* fall through */
1079
1080         case CSR_STATE_CLEAR:
1081         case CSR_STATE_SET:
1082         case CSR_CYCLE_TIME:
1083         case CSR_BUS_TIME:
1084         case CSR_BUSY_TIMEOUT:
1085                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1086                         *data = cpu_to_be32(card->driver->read_csr(card, reg));
1087                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1088                         card->driver->write_csr(card, reg, be32_to_cpu(*data));
1089                 else
1090                         rcode = RCODE_TYPE_ERROR;
1091                 break;
1092
1093         case CSR_RESET_START:
1094                 if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1095                         card->driver->write_csr(card, CSR_STATE_CLEAR,
1096                                                 CSR_STATE_BIT_ABDICATE);
1097                 else
1098                         rcode = RCODE_TYPE_ERROR;
1099                 break;
1100
1101         case CSR_SPLIT_TIMEOUT_HI:
1102                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1103                         *data = cpu_to_be32(card->split_timeout_hi);
1104                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1105                         spin_lock_irqsave(&card->lock, flags);
1106                         card->split_timeout_hi = be32_to_cpu(*data) & 7;
1107                         update_split_timeout(card);
1108                         spin_unlock_irqrestore(&card->lock, flags);
1109                 } else {
1110                         rcode = RCODE_TYPE_ERROR;
1111                 }
1112                 break;
1113
1114         case CSR_SPLIT_TIMEOUT_LO:
1115                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1116                         *data = cpu_to_be32(card->split_timeout_lo);
1117                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1118                         spin_lock_irqsave(&card->lock, flags);
1119                         card->split_timeout_lo =
1120                                         be32_to_cpu(*data) & 0xfff80000;
1121                         update_split_timeout(card);
1122                         spin_unlock_irqrestore(&card->lock, flags);
1123                 } else {
1124                         rcode = RCODE_TYPE_ERROR;
1125                 }
1126                 break;
1127
1128         case CSR_MAINT_UTILITY:
1129                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1130                         *data = card->maint_utility_register;
1131                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1132                         card->maint_utility_register = *data;
1133                 else
1134                         rcode = RCODE_TYPE_ERROR;
1135                 break;
1136
1137         case CSR_BROADCAST_CHANNEL:
1138                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1139                         *data = cpu_to_be32(card->broadcast_channel);
1140                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1141                         card->broadcast_channel =
1142                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1143                             BROADCAST_CHANNEL_INITIAL;
1144                 else
1145                         rcode = RCODE_TYPE_ERROR;
1146                 break;
1147
1148         case CSR_BUS_MANAGER_ID:
1149         case CSR_BANDWIDTH_AVAILABLE:
1150         case CSR_CHANNELS_AVAILABLE_HI:
1151         case CSR_CHANNELS_AVAILABLE_LO:
1152                 /*
1153                  * FIXME: these are handled by the OHCI hardware and
1154                  * the stack never sees these request. If we add
1155                  * support for a new type of controller that doesn't
1156                  * handle this in hardware we need to deal with these
1157                  * transactions.
1158                  */
1159                 BUG();
1160                 break;
1161
1162         default:
1163                 rcode = RCODE_ADDRESS_ERROR;
1164                 break;
1165         }
1166
1167         fw_send_response(card, request, rcode);
1168 }
1169
1170 static struct fw_address_handler registers = {
1171         .length                 = 0x400,
1172         .address_callback       = handle_registers,
1173 };
1174
1175 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1176 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1177 MODULE_LICENSE("GPL");
1178
1179 static const u32 vendor_textual_descriptor[] = {
1180         /* textual descriptor leaf () */
1181         0x00060000,
1182         0x00000000,
1183         0x00000000,
1184         0x4c696e75,             /* L i n u */
1185         0x78204669,             /* x   F i */
1186         0x72657769,             /* r e w i */
1187         0x72650000,             /* r e     */
1188 };
1189
1190 static const u32 model_textual_descriptor[] = {
1191         /* model descriptor leaf () */
1192         0x00030000,
1193         0x00000000,
1194         0x00000000,
1195         0x4a756a75,             /* J u j u */
1196 };
1197
1198 static struct fw_descriptor vendor_id_descriptor = {
1199         .length = ARRAY_SIZE(vendor_textual_descriptor),
1200         .immediate = 0x03d00d1e,
1201         .key = 0x81000000,
1202         .data = vendor_textual_descriptor,
1203 };
1204
1205 static struct fw_descriptor model_id_descriptor = {
1206         .length = ARRAY_SIZE(model_textual_descriptor),
1207         .immediate = 0x17000001,
1208         .key = 0x81000000,
1209         .data = model_textual_descriptor,
1210 };
1211
1212 static int __init fw_core_init(void)
1213 {
1214         int ret;
1215
1216         ret = bus_register(&fw_bus_type);
1217         if (ret < 0)
1218                 return ret;
1219
1220         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1221         if (fw_cdev_major < 0) {
1222                 bus_unregister(&fw_bus_type);
1223                 return fw_cdev_major;
1224         }
1225
1226         fw_core_add_address_handler(&topology_map, &topology_map_region);
1227         fw_core_add_address_handler(&registers, &registers_region);
1228         fw_core_add_descriptor(&vendor_id_descriptor);
1229         fw_core_add_descriptor(&model_id_descriptor);
1230
1231         return 0;
1232 }
1233
1234 static void __exit fw_core_cleanup(void)
1235 {
1236         unregister_chrdev(fw_cdev_major, "firewire");
1237         bus_unregister(&fw_bus_type);
1238         idr_destroy(&fw_device_idr);
1239 }
1240
1241 module_init(fw_core_init);
1242 module_exit(fw_core_cleanup);