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 #include <linux/workqueue.h>
  40
  41 #include <asm/byteorder.h>
  42
  43 #include "core.h"
  44
  45 #define HEADER_PRI(pri)                 ((pri) << 0)
  46 #define HEADER_TCODE(tcode)             ((tcode) << 4)
  47 #define HEADER_RETRY(retry)             ((retry) << 8)
  48 #define HEADER_TLABEL(tlabel)           ((tlabel) << 10)
  49 #define HEADER_DESTINATION(destination) ((destination) << 16)
  50 #define HEADER_SOURCE(source)           ((source) << 16)
  51 #define HEADER_RCODE(rcode)             ((rcode) << 12)
  52 #define HEADER_OFFSET_HIGH(offset_high) ((offset_high) << 0)
  53 #define HEADER_DATA_LENGTH(length)      ((length) << 16)
  54 #define HEADER_EXTENDED_TCODE(tcode)    ((tcode) << 0)
  55
  56 #define HEADER_GET_TCODE(q)             (((q) >> 4) & 0x0f)
  57 #define HEADER_GET_TLABEL(q)            (((q) >> 10) & 0x3f)
  58 #define HEADER_GET_RCODE(q)             (((q) >> 12) & 0x0f)
  59 #define HEADER_GET_DESTINATION(q)       (((q) >> 16) & 0xffff)
  60 #define HEADER_GET_SOURCE(q)            (((q) >> 16) & 0xffff)
  61 #define HEADER_GET_OFFSET_HIGH(q)       (((q) >> 0) & 0xffff)
  62 #define HEADER_GET_DATA_LENGTH(q)       (((q) >> 16) & 0xffff)
  63 #define HEADER_GET_EXTENDED_TCODE(q)    (((q) >> 0) & 0xffff)
  64
  65 #define HEADER_DESTINATION_IS_BROADCAST(q) \
  66         (((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
  67
  68 #define PHY_PACKET_CONFIG       0x0
  69 #define PHY_PACKET_LINK_ON      0x1
  70 #define PHY_PACKET_SELF_ID      0x2
  71
  72 #define PHY_CONFIG_GAP_COUNT(gap_count) (((gap_count) << 16) | (1 << 22))
  73 #define PHY_CONFIG_ROOT_ID(node_id)     ((((node_id) & 0x3f) << 24) | (1 << 23))
  74 #define PHY_IDENTIFIER(id)              ((id) << 30)
  75
  76 /* returns 0 if the split timeout handler is already running */
  77 static int try_cancel_split_timeout(struct fw_transaction *t)
  78 {
  79         if (t->is_split_transaction)
  80                 return del_timer(&t->split_timeout_timer);
  81         else
  82                 return 1;
  83 }
  84
  85 static int close_transaction(struct fw_transaction *transaction,
  86                              struct fw_card *card, int rcode)
  87 {
  88         struct fw_transaction *t;
  89         unsigned long flags;
  90
  91         spin_lock_irqsave(&card->lock, flags);
  92         list_for_each_entry(t, &card->transaction_list, link) {
  93                 if (t == transaction) {
  94                         if (!try_cancel_split_timeout(t)) {
  95                                 spin_unlock_irqrestore(&card->lock, flags);
  96                                 goto timed_out;
  97                         }
  98                         list_del_init(&t->link);
  99                         card->tlabel_mask &= ~(1ULL << t->tlabel);
 100                         break;
 101                 }
 102         }
 103         spin_unlock_irqrestore(&card->lock, flags);
 104
 105         if (&t->link != &card->transaction_list) {
 106                 t->callback(card, rcode, NULL, 0, t->callback_data);
 107                 return 0;
 108         }
 109
 110  timed_out:
 111         return -ENOENT;
 112 }
 113
 114 /*
 115  * Only valid for transactions that are potentially pending (ie have
 116  * been sent).
 117  */
 118 int fw_cancel_transaction(struct fw_card *card,
 119                           struct fw_transaction *transaction)
 120 {
 121         /*
 122          * Cancel the packet transmission if it's still queued.  That
 123          * will call the packet transmission callback which cancels
 124          * the transaction.
 125          */
 126
 127         if (card->driver->cancel_packet(card, &transaction->packet) == 0)
 128                 return 0;
 129
 130         /*
 131          * If the request packet has already been sent, we need to see
 132          * if the transaction is still pending and remove it in that case.
 133          */
 134
 135         return close_transaction(transaction, card, RCODE_CANCELLED);
 136 }
 137 EXPORT_SYMBOL(fw_cancel_transaction);
 138
 139 static void split_transaction_timeout_callback(unsigned long data)
 140 {
 141         struct fw_transaction *t = (struct fw_transaction *)data;
 142         struct fw_card *card = t->card;
 143         unsigned long flags;
 144
 145         spin_lock_irqsave(&card->lock, flags);
 146         if (list_empty(&t->link)) {
 147                 spin_unlock_irqrestore(&card->lock, flags);
 148                 return;
 149         }
 150         list_del(&t->link);
 151         card->tlabel_mask &= ~(1ULL << t->tlabel);
 152         spin_unlock_irqrestore(&card->lock, flags);
 153
 154         t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
 155 }
 156
 157 static void start_split_transaction_timeout(struct fw_transaction *t,
 158                                             struct fw_card *card)
 159 {
 160         unsigned long flags;
 161
 162         spin_lock_irqsave(&card->lock, flags);
 163
 164         if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
 165                 spin_unlock_irqrestore(&card->lock, flags);
 166                 return;
 167         }
 168
 169         t->is_split_transaction = true;
 170         mod_timer(&t->split_timeout_timer,
 171                   jiffies + card->split_timeout_jiffies);
 172
 173         spin_unlock_irqrestore(&card->lock, flags);
 174 }
 175
 176 static void transmit_complete_callback(struct fw_packet *packet,
 177                                        struct fw_card *card, int status)
 178 {
 179         struct fw_transaction *t =
 180             container_of(packet, struct fw_transaction, packet);
 181
 182         switch (status) {
 183         case ACK_COMPLETE:
 184                 close_transaction(t, card, RCODE_COMPLETE);
 185                 break;
 186         case ACK_PENDING:
 187                 start_split_transaction_timeout(t, card);
 188                 break;
 189         case ACK_BUSY_X:
 190         case ACK_BUSY_A:
 191         case ACK_BUSY_B:
 192                 close_transaction(t, card, RCODE_BUSY);
 193                 break;
 194         case ACK_DATA_ERROR:
 195                 close_transaction(t, card, RCODE_DATA_ERROR);
 196                 break;
 197         case ACK_TYPE_ERROR:
 198                 close_transaction(t, card, RCODE_TYPE_ERROR);
 199                 break;
 200         default:
 201                 /*
 202                  * In this case the ack is really a juju specific
 203                  * rcode, so just forward that to the callback.
 204                  */
 205                 close_transaction(t, card, status);
 206                 break;
 207         }
 208 }
 209
 210 static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
 211                 int destination_id, int source_id, int generation, int speed,
 212                 unsigned long long offset, void *payload, size_t length)
 213 {
 214         int ext_tcode;
 215
 216         if (tcode == TCODE_STREAM_DATA) {
 217                 packet->header[0] =
 218                         HEADER_DATA_LENGTH(length) |
 219                         destination_id |
 220                         HEADER_TCODE(TCODE_STREAM_DATA);
 221                 packet->header_length = 4;
 222                 packet->payload = payload;
 223                 packet->payload_length = length;
 224
 225                 goto common;
 226         }
 227
 228         if (tcode > 0x10) {
 229                 ext_tcode = tcode & ~0x10;
 230                 tcode = TCODE_LOCK_REQUEST;
 231         } else
 232                 ext_tcode = 0;
 233
 234         packet->header[0] =
 235                 HEADER_RETRY(RETRY_X) |
 236                 HEADER_TLABEL(tlabel) |
 237                 HEADER_TCODE(tcode) |
 238                 HEADER_DESTINATION(destination_id);
 239         packet->header[1] =
 240                 HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
 241         packet->header[2] =
 242                 offset;
 243
 244         switch (tcode) {
 245         case TCODE_WRITE_QUADLET_REQUEST:
 246                 packet->header[3] = *(u32 *)payload;
 247                 packet->header_length = 16;
 248                 packet->payload_length = 0;
 249                 break;
 250
 251         case TCODE_LOCK_REQUEST:
 252         case TCODE_WRITE_BLOCK_REQUEST:
 253                 packet->header[3] =
 254                         HEADER_DATA_LENGTH(length) |
 255                         HEADER_EXTENDED_TCODE(ext_tcode);
 256                 packet->header_length = 16;
 257                 packet->payload = payload;
 258                 packet->payload_length = length;
 259                 break;
 260
 261         case TCODE_READ_QUADLET_REQUEST:
 262                 packet->header_length = 12;
 263                 packet->payload_length = 0;
 264                 break;
 265
 266         case TCODE_READ_BLOCK_REQUEST:
 267                 packet->header[3] =
 268                         HEADER_DATA_LENGTH(length) |
 269                         HEADER_EXTENDED_TCODE(ext_tcode);
 270                 packet->header_length = 16;
 271                 packet->payload_length = 0;
 272                 break;
 273
 274         default:
 275                 WARN(1, "wrong tcode %d\n", tcode);
 276         }
 277  common:
 278         packet->speed = speed;
 279         packet->generation = generation;
 280         packet->ack = 0;
 281         packet->payload_mapped = false;
 282 }
 283
 284 static int allocate_tlabel(struct fw_card *card)
 285 {
 286         int tlabel;
 287
 288         tlabel = card->current_tlabel;
 289         while (card->tlabel_mask & (1ULL << tlabel)) {
 290                 tlabel = (tlabel + 1) & 0x3f;
 291                 if (tlabel == card->current_tlabel)
 292                         return -EBUSY;
 293         }
 294
 295         card->current_tlabel = (tlabel + 1) & 0x3f;
 296         card->tlabel_mask |= 1ULL << tlabel;
 297
 298         return tlabel;
 299 }
 300
 301 /**
 302  * fw_send_request() - submit a request packet for transmission
 303  * @card:               interface to send the request at
 304  * @t:                  transaction instance to which the request belongs
 305  * @tcode:              transaction code
 306  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
 307  * @generation:         bus generation in which request and response are valid
 308  * @speed:              transmission speed
 309  * @offset:             48bit wide offset into destination's address space
 310  * @payload:            data payload for the request subaction
 311  * @length:             length of the payload, in bytes
 312  * @callback:           function to be called when the transaction is completed
 313  * @callback_data:      data to be passed to the transaction completion callback
 314  *
 315  * Submit a request packet into the asynchronous request transmission queue.
 316  * Can be called from atomic context.  If you prefer a blocking API, use
 317  * fw_run_transaction() in a context that can sleep.
 318  *
 319  * In case of lock requests, specify one of the firewire-core specific %TCODE_
 320  * constants instead of %TCODE_LOCK_REQUEST in @tcode.
 321  *
 322  * Make sure that the value in @destination_id is not older than the one in
 323  * @generation.  Otherwise the request is in danger to be sent to a wrong node.
 324  *
 325  * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
 326  * needs to synthesize @destination_id with fw_stream_packet_destination_id().
 327  * It will contain tag, channel, and sy data instead of a node ID then.
 328  *
 329  * The payload buffer at @data is going to be DMA-mapped except in case of
 330  * @length <= 8 or of local (loopback) requests.  Hence make sure that the
 331  * buffer complies with the restrictions of the streaming DMA mapping API.
 332  * @payload must not be freed before the @callback is called.
 333  *
 334  * In case of request types without payload, @data is NULL and @length is 0.
 335  *
 336  * After the transaction is completed successfully or unsuccessfully, the
 337  * @callback will be called.  Among its parameters is the response code which
 338  * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
 339  * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
 340  * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
 341  * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
 342  * generation, or missing ACK respectively.
 343  *
 344  * Note some timing corner cases:  fw_send_request() may complete much earlier
 345  * than when the request packet actually hits the wire.  On the other hand,
 346  * transaction completion and hence execution of @callback may happen even
 347  * before fw_send_request() returns.
 348  */
 349 void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 350                      int destination_id, int generation, int speed,
 351                      unsigned long long offset, void *payload, size_t length,
 352                      fw_transaction_callback_t callback, void *callback_data)
 353 {
 354         unsigned long flags;
 355         int tlabel;
 356
 357         /*
 358          * Allocate tlabel from the bitmap and put the transaction on
 359          * the list while holding the card spinlock.
 360          */
 361
 362         spin_lock_irqsave(&card->lock, flags);
 363
 364         tlabel = allocate_tlabel(card);
 365         if (tlabel < 0) {
 366                 spin_unlock_irqrestore(&card->lock, flags);
 367                 callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
 368                 return;
 369         }
 370
 371         t->node_id = destination_id;
 372         t->tlabel = tlabel;
 373         t->card = card;
 374         t->is_split_transaction = false;
 375         setup_timer(&t->split_timeout_timer,
 376                     split_transaction_timeout_callback, (unsigned long)t);
 377         t->callback = callback;
 378         t->callback_data = callback_data;
 379
 380         fw_fill_request(&t->packet, tcode, t->tlabel,
 381                         destination_id, card->node_id, generation,
 382                         speed, offset, payload, length);
 383         t->packet.callback = transmit_complete_callback;
 384
 385         list_add_tail(&t->link, &card->transaction_list);
 386
 387         spin_unlock_irqrestore(&card->lock, flags);
 388
 389         card->driver->send_request(card, &t->packet);
 390 }
 391 EXPORT_SYMBOL(fw_send_request);
 392
 393 struct transaction_callback_data {
 394         struct completion done;
 395         void *payload;
 396         int rcode;
 397 };
 398
 399 static void transaction_callback(struct fw_card *card, int rcode,
 400                                  void *payload, size_t length, void *data)
 401 {
 402         struct transaction_callback_data *d = data;
 403
 404         if (rcode == RCODE_COMPLETE)
 405                 memcpy(d->payload, payload, length);
 406         d->rcode = rcode;
 407         complete(&d->done);
 408 }
 409
 410 /**
 411  * fw_run_transaction() - send request and sleep until transaction is completed
 412  *
 413  * Returns the RCODE.  See fw_send_request() for parameter documentation.
 414  * Unlike fw_send_request(), @data points to the payload of the request or/and
 415  * to the payload of the response.  DMA mapping restrictions apply to outbound
 416  * request payloads of >= 8 bytes but not to inbound response payloads.
 417  */
 418 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 419                        int generation, int speed, unsigned long long offset,
 420                        void *payload, size_t length)
 421 {
 422         struct transaction_callback_data d;
 423         struct fw_transaction t;
 424
 425         init_timer_on_stack(&t.split_timeout_timer);
 426         init_completion(&d.done);
 427         d.payload = payload;
 428         fw_send_request(card, &t, tcode, destination_id, generation, speed,
 429                         offset, payload, length, transaction_callback, &d);
 430         wait_for_completion(&d.done);
 431         destroy_timer_on_stack(&t.split_timeout_timer);
 432
 433         return d.rcode;
 434 }
 435 EXPORT_SYMBOL(fw_run_transaction);
 436
 437 static DEFINE_MUTEX(phy_config_mutex);
 438 static DECLARE_COMPLETION(phy_config_done);
 439
 440 static void transmit_phy_packet_callback(struct fw_packet *packet,
 441                                          struct fw_card *card, int status)
 442 {
 443         complete(&phy_config_done);
 444 }
 445
 446 static struct fw_packet phy_config_packet = {
 447         .header_length  = 12,
 448         .header[0]      = TCODE_LINK_INTERNAL << 4,
 449         .payload_length = 0,
 450         .speed          = SCODE_100,
 451         .callback       = transmit_phy_packet_callback,
 452 };
 453
 454 void fw_send_phy_config(struct fw_card *card,
 455                         int node_id, int generation, int gap_count)
 456 {
 457         long timeout = DIV_ROUND_UP(HZ, 10);
 458         u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
 459
 460         if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
 461                 data |= PHY_CONFIG_ROOT_ID(node_id);
 462
 463         if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
 464                 gap_count = card->driver->read_phy_reg(card, 1);
 465                 if (gap_count < 0)
 466                         return;
 467
 468                 gap_count &= 63;
 469                 if (gap_count == 63)
 470                         return;
 471         }
 472         data |= PHY_CONFIG_GAP_COUNT(gap_count);
 473
 474         mutex_lock(&phy_config_mutex);
 475
 476         phy_config_packet.header[1] = data;
 477         phy_config_packet.header[2] = ~data;
 478         phy_config_packet.generation = generation;
 479         INIT_COMPLETION(phy_config_done);
 480
 481         card->driver->send_request(card, &phy_config_packet);
 482         wait_for_completion_timeout(&phy_config_done, timeout);
 483
 484         mutex_unlock(&phy_config_mutex);
 485 }
 486
 487 static struct fw_address_handler *lookup_overlapping_address_handler(
 488         struct list_head *list, unsigned long long offset, size_t length)
 489 {
 490         struct fw_address_handler *handler;
 491
 492         list_for_each_entry(handler, list, link) {
 493                 if (handler->offset < offset + length &&
 494                     offset < handler->offset + handler->length)
 495                         return handler;
 496         }
 497
 498         return NULL;
 499 }
 500
 501 static bool is_enclosing_handler(struct fw_address_handler *handler,
 502                                  unsigned long long offset, size_t length)
 503 {
 504         return handler->offset <= offset &&
 505                 offset + length <= handler->offset + handler->length;
 506 }
 507
 508 static struct fw_address_handler *lookup_enclosing_address_handler(
 509         struct list_head *list, unsigned long long offset, size_t length)
 510 {
 511         struct fw_address_handler *handler;
 512
 513         list_for_each_entry(handler, list, link) {
 514                 if (is_enclosing_handler(handler, offset, length))
 515                         return handler;
 516         }
 517
 518         return NULL;
 519 }
 520
 521 static DEFINE_SPINLOCK(address_handler_lock);
 522 static LIST_HEAD(address_handler_list);
 523
 524 const struct fw_address_region fw_high_memory_region =
 525         { .start = 0x000100000000ULL, .end = 0xffffe0000000ULL,  };
 526 EXPORT_SYMBOL(fw_high_memory_region);
 527
 528 #if 0
 529 const struct fw_address_region fw_low_memory_region =
 530         { .start = 0x000000000000ULL, .end = 0x000100000000ULL,  };
 531 const struct fw_address_region fw_private_region =
 532         { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 533 const struct fw_address_region fw_csr_region =
 534         { .start = CSR_REGISTER_BASE,
 535           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 536 const struct fw_address_region fw_unit_space_region =
 537         { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 538 #endif  /*  0  */
 539
 540 static bool is_in_fcp_region(u64 offset, size_t length)
 541 {
 542         return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 543                 offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
 544 }
 545
 546 /**
 547  * fw_core_add_address_handler() - register for incoming requests
 548  * @handler:    callback
 549  * @region:     region in the IEEE 1212 node space address range
 550  *
 551  * region->start, ->end, and handler->length have to be quadlet-aligned.
 552  *
 553  * When a request is received that falls within the specified address range,
 554  * the specified callback is invoked.  The parameters passed to the callback
 555  * give the details of the particular request.
 556  *
 557  * Return value:  0 on success, non-zero otherwise.
 558  *
 559  * The start offset of the handler's address region is determined by
 560  * fw_core_add_address_handler() and is returned in handler->offset.
 561  *
 562  * Address allocations are exclusive, except for the FCP registers.
 563  */
 564 int fw_core_add_address_handler(struct fw_address_handler *handler,
 565                                 const struct fw_address_region *region)
 566 {
 567         struct fw_address_handler *other;
 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_bh(&address_handler_lock);
 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_bh(&address_handler_lock);
 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  * When fw_core_remove_address_handler() returns, @handler->callback() is
 606  * guaranteed to not run on any CPU anymore.
 607  */
 608 void fw_core_remove_address_handler(struct fw_address_handler *handler)
 609 {
 610         spin_lock_bh(&address_handler_lock);
 611         list_del(&handler->link);
 612         spin_unlock_bh(&address_handler_lock);
 613 }
 614 EXPORT_SYMBOL(fw_core_remove_address_handler);
 615
 616 struct fw_request {
 617         struct fw_packet response;
 618         u32 request_header[4];
 619         int ack;
 620         u32 length;
 621         u32 data[0];
 622 };
 623
 624 static void free_response_callback(struct fw_packet *packet,
 625                                    struct fw_card *card, int status)
 626 {
 627         struct fw_request *request;
 628
 629         request = container_of(packet, struct fw_request, response);
 630         kfree(request);
 631 }
 632
 633 int fw_get_response_length(struct fw_request *r)
 634 {
 635         int tcode, ext_tcode, data_length;
 636
 637         tcode = HEADER_GET_TCODE(r->request_header[0]);
 638
 639         switch (tcode) {
 640         case TCODE_WRITE_QUADLET_REQUEST:
 641         case TCODE_WRITE_BLOCK_REQUEST:
 642                 return 0;
 643
 644         case TCODE_READ_QUADLET_REQUEST:
 645                 return 4;
 646
 647         case TCODE_READ_BLOCK_REQUEST:
 648                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 649                 return data_length;
 650
 651         case TCODE_LOCK_REQUEST:
 652                 ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
 653                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 654                 switch (ext_tcode) {
 655                 case EXTCODE_FETCH_ADD:
 656                 case EXTCODE_LITTLE_ADD:
 657                         return data_length;
 658                 default:
 659                         return data_length / 2;
 660                 }
 661
 662         default:
 663                 WARN(1, "wrong tcode %d\n", tcode);
 664                 return 0;
 665         }
 666 }
 667
 668 void fw_fill_response(struct fw_packet *response, u32 *request_header,
 669                       int rcode, void *payload, size_t length)
 670 {
 671         int tcode, tlabel, extended_tcode, source, destination;
 672
 673         tcode          = HEADER_GET_TCODE(request_header[0]);
 674         tlabel         = HEADER_GET_TLABEL(request_header[0]);
 675         source         = HEADER_GET_DESTINATION(request_header[0]);
 676         destination    = HEADER_GET_SOURCE(request_header[1]);
 677         extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 678
 679         response->header[0] =
 680                 HEADER_RETRY(RETRY_1) |
 681                 HEADER_TLABEL(tlabel) |
 682                 HEADER_DESTINATION(destination);
 683         response->header[1] =
 684                 HEADER_SOURCE(source) |
 685                 HEADER_RCODE(rcode);
 686         response->header[2] = 0;
 687
 688         switch (tcode) {
 689         case TCODE_WRITE_QUADLET_REQUEST:
 690         case TCODE_WRITE_BLOCK_REQUEST:
 691                 response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 692                 response->header_length = 12;
 693                 response->payload_length = 0;
 694                 break;
 695
 696         case TCODE_READ_QUADLET_REQUEST:
 697                 response->header[0] |=
 698                         HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 699                 if (payload != NULL)
 700                         response->header[3] = *(u32 *)payload;
 701                 else
 702                         response->header[3] = 0;
 703                 response->header_length = 16;
 704                 response->payload_length = 0;
 705                 break;
 706
 707         case TCODE_READ_BLOCK_REQUEST:
 708         case TCODE_LOCK_REQUEST:
 709                 response->header[0] |= HEADER_TCODE(tcode + 2);
 710                 response->header[3] =
 711                         HEADER_DATA_LENGTH(length) |
 712                         HEADER_EXTENDED_TCODE(extended_tcode);
 713                 response->header_length = 16;
 714                 response->payload = payload;
 715                 response->payload_length = length;
 716                 break;
 717
 718         default:
 719                 WARN(1, "wrong tcode %d\n", tcode);
 720         }
 721
 722         response->payload_mapped = false;
 723 }
 724 EXPORT_SYMBOL(fw_fill_response);
 725
 726 static u32 compute_split_timeout_timestamp(struct fw_card *card,
 727                                            u32 request_timestamp)
 728 {
 729         unsigned int cycles;
 730         u32 timestamp;
 731
 732         cycles = card->split_timeout_cycles;
 733         cycles += request_timestamp & 0x1fff;
 734
 735         timestamp = request_timestamp & ~0x1fff;
 736         timestamp += (cycles / 8000) << 13;
 737         timestamp |= cycles % 8000;
 738
 739         return timestamp;
 740 }
 741
 742 static struct fw_request *allocate_request(struct fw_card *card,
 743                                            struct fw_packet *p)
 744 {
 745         struct fw_request *request;
 746         u32 *data, length;
 747         int request_tcode;
 748
 749         request_tcode = HEADER_GET_TCODE(p->header[0]);
 750         switch (request_tcode) {
 751         case TCODE_WRITE_QUADLET_REQUEST:
 752                 data = &p->header[3];
 753                 length = 4;
 754                 break;
 755
 756         case TCODE_WRITE_BLOCK_REQUEST:
 757         case TCODE_LOCK_REQUEST:
 758                 data = p->payload;
 759                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 760                 break;
 761
 762         case TCODE_READ_QUADLET_REQUEST:
 763                 data = NULL;
 764                 length = 4;
 765                 break;
 766
 767         case TCODE_READ_BLOCK_REQUEST:
 768                 data = NULL;
 769                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 770                 break;
 771
 772         default:
 773                 fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
 774                          p->header[0], p->header[1], p->header[2]);
 775                 return NULL;
 776         }
 777
 778         request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 779         if (request == NULL)
 780                 return NULL;
 781
 782         request->response.speed = p->speed;
 783         request->response.timestamp =
 784                         compute_split_timeout_timestamp(card, p->timestamp);
 785         request->response.generation = p->generation;
 786         request->response.ack = 0;
 787         request->response.callback = free_response_callback;
 788         request->ack = p->ack;
 789         request->length = length;
 790         if (data)
 791                 memcpy(request->data, data, length);
 792
 793         memcpy(request->request_header, p->header, sizeof(p->header));
 794
 795         return request;
 796 }
 797
 798 void fw_send_response(struct fw_card *card,
 799                       struct fw_request *request, int rcode)
 800 {
 801         if (WARN_ONCE(!request, "invalid for FCP address handlers"))
 802                 return;
 803
 804         /* unified transaction or broadcast transaction: don't respond */
 805         if (request->ack != ACK_PENDING ||
 806             HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 807                 kfree(request);
 808                 return;
 809         }
 810
 811         if (rcode == RCODE_COMPLETE)
 812                 fw_fill_response(&request->response, request->request_header,
 813                                  rcode, request->data,
 814                                  fw_get_response_length(request));
 815         else
 816                 fw_fill_response(&request->response, request->request_header,
 817                                  rcode, NULL, 0);
 818
 819         card->driver->send_response(card, &request->response);
 820 }
 821 EXPORT_SYMBOL(fw_send_response);
 822
 823 /**
 824  * fw_get_request_speed() - returns speed at which the @request was received
 825  */
 826 int fw_get_request_speed(struct fw_request *request)
 827 {
 828         return request->response.speed;
 829 }
 830 EXPORT_SYMBOL(fw_get_request_speed);
 831
 832 static void handle_exclusive_region_request(struct fw_card *card,
 833                                             struct fw_packet *p,
 834                                             struct fw_request *request,
 835                                             unsigned long long offset)
 836 {
 837         struct fw_address_handler *handler;
 838         int tcode, destination, source;
 839
 840         destination = HEADER_GET_DESTINATION(p->header[0]);
 841         source      = HEADER_GET_SOURCE(p->header[1]);
 842         tcode       = HEADER_GET_TCODE(p->header[0]);
 843         if (tcode == TCODE_LOCK_REQUEST)
 844                 tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 845
 846         spin_lock_bh(&address_handler_lock);
 847         handler = lookup_enclosing_address_handler(&address_handler_list,
 848                                                    offset, request->length);
 849         if (handler)
 850                 handler->address_callback(card, request,
 851                                           tcode, destination, source,
 852                                           p->generation, offset,
 853                                           request->data, request->length,
 854                                           handler->callback_data);
 855         spin_unlock_bh(&address_handler_lock);
 856
 857         if (!handler)
 858                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 859 }
 860
 861 static void handle_fcp_region_request(struct fw_card *card,
 862                                       struct fw_packet *p,
 863                                       struct fw_request *request,
 864                                       unsigned long long offset)
 865 {
 866         struct fw_address_handler *handler;
 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_bh(&address_handler_lock);
 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_bh(&address_handler_lock);
 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_notice(card, "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 /**
1007  * fw_rcode_string - convert a firewire result code to an error description
1008  * @rcode: the result code
1009  */
1010 const char *fw_rcode_string(int rcode)
1011 {
1012         static const char *const names[] = {
1013                 [RCODE_COMPLETE]       = "no error",
1014                 [RCODE_CONFLICT_ERROR] = "conflict error",
1015                 [RCODE_DATA_ERROR]     = "data error",
1016                 [RCODE_TYPE_ERROR]     = "type error",
1017                 [RCODE_ADDRESS_ERROR]  = "address error",
1018                 [RCODE_SEND_ERROR]     = "send error",
1019                 [RCODE_CANCELLED]      = "timeout",
1020                 [RCODE_BUSY]           = "busy",
1021                 [RCODE_GENERATION]     = "bus reset",
1022                 [RCODE_NO_ACK]         = "no ack",
1023         };
1024
1025         if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1026                 return names[rcode];
1027         else
1028                 return "unknown";
1029 }
1030 EXPORT_SYMBOL(fw_rcode_string);
1031
1032 static const struct fw_address_region topology_map_region =
1033         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1034           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1035
1036 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1037                 int tcode, int destination, int source, int generation,
1038                 unsigned long long offset, void *payload, size_t length,
1039                 void *callback_data)
1040 {
1041         int start;
1042
1043         if (!TCODE_IS_READ_REQUEST(tcode)) {
1044                 fw_send_response(card, request, RCODE_TYPE_ERROR);
1045                 return;
1046         }
1047
1048         if ((offset & 3) > 0 || (length & 3) > 0) {
1049                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1050                 return;
1051         }
1052
1053         start = (offset - topology_map_region.start) / 4;
1054         memcpy(payload, &card->topology_map[start], length);
1055
1056         fw_send_response(card, request, RCODE_COMPLETE);
1057 }
1058
1059 static struct fw_address_handler topology_map = {
1060         .length                 = 0x400,
1061         .address_callback       = handle_topology_map,
1062 };
1063
1064 static const struct fw_address_region registers_region =
1065         { .start = CSR_REGISTER_BASE,
1066           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1067
1068 static void update_split_timeout(struct fw_card *card)
1069 {
1070         unsigned int cycles;
1071
1072         cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1073
1074         /* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1075         cycles = clamp(cycles, 800u, 3u * 8000u);
1076
1077         card->split_timeout_cycles = cycles;
1078         card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1079 }
1080
1081 static void handle_registers(struct fw_card *card, struct fw_request *request,
1082                 int tcode, int destination, int source, int generation,
1083                 unsigned long long offset, void *payload, size_t length,
1084                 void *callback_data)
1085 {
1086         int reg = offset & ~CSR_REGISTER_BASE;
1087         __be32 *data = payload;
1088         int rcode = RCODE_COMPLETE;
1089         unsigned long flags;
1090
1091         switch (reg) {
1092         case CSR_PRIORITY_BUDGET:
1093                 if (!card->priority_budget_implemented) {
1094                         rcode = RCODE_ADDRESS_ERROR;
1095                         break;
1096                 }
1097                 /* else fall through */
1098
1099         case CSR_NODE_IDS:
1100                 /*
1101                  * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1102                  * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1103                  */
1104                 /* fall through */
1105
1106         case CSR_STATE_CLEAR:
1107         case CSR_STATE_SET:
1108         case CSR_CYCLE_TIME:
1109         case CSR_BUS_TIME:
1110         case CSR_BUSY_TIMEOUT:
1111                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1112                         *data = cpu_to_be32(card->driver->read_csr(card, reg));
1113                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1114                         card->driver->write_csr(card, reg, be32_to_cpu(*data));
1115                 else
1116                         rcode = RCODE_TYPE_ERROR;
1117                 break;
1118
1119         case CSR_RESET_START:
1120                 if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1121                         card->driver->write_csr(card, CSR_STATE_CLEAR,
1122                                                 CSR_STATE_BIT_ABDICATE);
1123                 else
1124                         rcode = RCODE_TYPE_ERROR;
1125                 break;
1126
1127         case CSR_SPLIT_TIMEOUT_HI:
1128                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1129                         *data = cpu_to_be32(card->split_timeout_hi);
1130                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1131                         spin_lock_irqsave(&card->lock, flags);
1132                         card->split_timeout_hi = be32_to_cpu(*data) & 7;
1133                         update_split_timeout(card);
1134                         spin_unlock_irqrestore(&card->lock, flags);
1135                 } else {
1136                         rcode = RCODE_TYPE_ERROR;
1137                 }
1138                 break;
1139
1140         case CSR_SPLIT_TIMEOUT_LO:
1141                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1142                         *data = cpu_to_be32(card->split_timeout_lo);
1143                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1144                         spin_lock_irqsave(&card->lock, flags);
1145                         card->split_timeout_lo =
1146                                         be32_to_cpu(*data) & 0xfff80000;
1147                         update_split_timeout(card);
1148                         spin_unlock_irqrestore(&card->lock, flags);
1149                 } else {
1150                         rcode = RCODE_TYPE_ERROR;
1151                 }
1152                 break;
1153
1154         case CSR_MAINT_UTILITY:
1155                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1156                         *data = card->maint_utility_register;
1157                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1158                         card->maint_utility_register = *data;
1159                 else
1160                         rcode = RCODE_TYPE_ERROR;
1161                 break;
1162
1163         case CSR_BROADCAST_CHANNEL:
1164                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1165                         *data = cpu_to_be32(card->broadcast_channel);
1166                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1167                         card->broadcast_channel =
1168                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1169                             BROADCAST_CHANNEL_INITIAL;
1170                 else
1171                         rcode = RCODE_TYPE_ERROR;
1172                 break;
1173
1174         case CSR_BUS_MANAGER_ID:
1175         case CSR_BANDWIDTH_AVAILABLE:
1176         case CSR_CHANNELS_AVAILABLE_HI:
1177         case CSR_CHANNELS_AVAILABLE_LO:
1178                 /*
1179                  * FIXME: these are handled by the OHCI hardware and
1180                  * the stack never sees these request. If we add
1181                  * support for a new type of controller that doesn't
1182                  * handle this in hardware we need to deal with these
1183                  * transactions.
1184                  */
1185                 BUG();
1186                 break;
1187
1188         default:
1189                 rcode = RCODE_ADDRESS_ERROR;
1190                 break;
1191         }
1192
1193         fw_send_response(card, request, rcode);
1194 }
1195
1196 static struct fw_address_handler registers = {
1197         .length                 = 0x400,
1198         .address_callback       = handle_registers,
1199 };
1200
1201 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1202 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1203 MODULE_LICENSE("GPL");
1204
1205 static const u32 vendor_textual_descriptor[] = {
1206         /* textual descriptor leaf () */
1207         0x00060000,
1208         0x00000000,
1209         0x00000000,
1210         0x4c696e75,             /* L i n u */
1211         0x78204669,             /* x   F i */
1212         0x72657769,             /* r e w i */
1213         0x72650000,             /* r e     */
1214 };
1215
1216 static const u32 model_textual_descriptor[] = {
1217         /* model descriptor leaf () */
1218         0x00030000,
1219         0x00000000,
1220         0x00000000,
1221         0x4a756a75,             /* J u j u */
1222 };
1223
1224 static struct fw_descriptor vendor_id_descriptor = {
1225         .length = ARRAY_SIZE(vendor_textual_descriptor),
1226         .immediate = 0x03d00d1e,
1227         .key = 0x81000000,
1228         .data = vendor_textual_descriptor,
1229 };
1230
1231 static struct fw_descriptor model_id_descriptor = {
1232         .length = ARRAY_SIZE(model_textual_descriptor),
1233         .immediate = 0x17000001,
1234         .key = 0x81000000,
1235         .data = model_textual_descriptor,
1236 };
1237
1238 static int __init fw_core_init(void)
1239 {
1240         int ret;
1241
1242         fw_workqueue = alloc_workqueue("firewire",
1243                                        WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0);
1244         if (!fw_workqueue)
1245                 return -ENOMEM;
1246
1247         ret = bus_register(&fw_bus_type);
1248         if (ret < 0) {
1249                 destroy_workqueue(fw_workqueue);
1250                 return ret;
1251         }
1252
1253         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1254         if (fw_cdev_major < 0) {
1255                 bus_unregister(&fw_bus_type);
1256                 destroy_workqueue(fw_workqueue);
1257                 return fw_cdev_major;
1258         }
1259
1260         fw_core_add_address_handler(&topology_map, &topology_map_region);
1261         fw_core_add_address_handler(&registers, &registers_region);
1262         fw_core_add_descriptor(&vendor_id_descriptor);
1263         fw_core_add_descriptor(&model_id_descriptor);
1264
1265         return 0;
1266 }
1267
1268 static void __exit fw_core_cleanup(void)
1269 {
1270         unregister_chrdev(fw_cdev_major, "firewire");
1271         bus_unregister(&fw_bus_type);
1272         destroy_workqueue(fw_workqueue);
1273         idr_destroy(&fw_device_idr);
1274 }
1275
1276 module_init(fw_core_init);
1277 module_exit(fw_core_cleanup);