linux/drivers/firewire/core-transaction.c
<<
>>
Prefs
   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 */
  77static 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
  85static 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 */
 118int 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}
 137EXPORT_SYMBOL(fw_cancel_transaction);
 138
 139static 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
 157static 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
 176static 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
 210static 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
 284static 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 */
 349void 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}
 391EXPORT_SYMBOL(fw_send_request);
 392
 393struct transaction_callback_data {
 394        struct completion done;
 395        void *payload;
 396        int rcode;
 397};
 398
 399static 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 */
 418int 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}
 435EXPORT_SYMBOL(fw_run_transaction);
 436
 437static DEFINE_MUTEX(phy_config_mutex);
 438static DECLARE_COMPLETION(phy_config_done);
 439
 440static void transmit_phy_packet_callback(struct fw_packet *packet,
 441                                         struct fw_card *card, int status)
 442{
 443        complete(&phy_config_done);
 444}
 445
 446static 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
 454void 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
 487static 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
 501static 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
 508static 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
 521static DEFINE_SPINLOCK(address_handler_lock);
 522static LIST_HEAD(address_handler_list);
 523
 524const struct fw_address_region fw_high_memory_region =
 525        { .start = 0x000100000000ULL, .end = 0xffffe0000000ULL,  };
 526EXPORT_SYMBOL(fw_high_memory_region);
 527
 528static const struct fw_address_region low_memory_region =
 529        { .start = 0x000000000000ULL, .end = 0x000100000000ULL,  };
 530
 531#if 0
 532const struct fw_address_region fw_private_region =
 533        { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 534const struct fw_address_region fw_csr_region =
 535        { .start = CSR_REGISTER_BASE,
 536          .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 537const struct fw_address_region fw_unit_space_region =
 538        { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 539#endif  /*  0  */
 540
 541static bool is_in_fcp_region(u64 offset, size_t length)
 542{
 543        return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 544                offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
 545}
 546
 547/**
 548 * fw_core_add_address_handler() - register for incoming requests
 549 * @handler:    callback
 550 * @region:     region in the IEEE 1212 node space address range
 551 *
 552 * region->start, ->end, and handler->length have to be quadlet-aligned.
 553 *
 554 * When a request is received that falls within the specified address range,
 555 * the specified callback is invoked.  The parameters passed to the callback
 556 * give the details of the particular request.
 557 *
 558 * Return value:  0 on success, non-zero otherwise.
 559 *
 560 * The start offset of the handler's address region is determined by
 561 * fw_core_add_address_handler() and is returned in handler->offset.
 562 *
 563 * Address allocations are exclusive, except for the FCP registers.
 564 */
 565int fw_core_add_address_handler(struct fw_address_handler *handler,
 566                                const struct fw_address_region *region)
 567{
 568        struct fw_address_handler *other;
 569        int ret = -EBUSY;
 570
 571        if (region->start & 0xffff000000000003ULL ||
 572            region->start >= region->end ||
 573            region->end   > 0x0001000000000000ULL ||
 574            handler->length & 3 ||
 575            handler->length == 0)
 576                return -EINVAL;
 577
 578        spin_lock_bh(&address_handler_lock);
 579
 580        handler->offset = region->start;
 581        while (handler->offset + handler->length <= region->end) {
 582                if (is_in_fcp_region(handler->offset, handler->length))
 583                        other = NULL;
 584                else
 585                        other = lookup_overlapping_address_handler
 586                                        (&address_handler_list,
 587                                         handler->offset, handler->length);
 588                if (other != NULL) {
 589                        handler->offset += other->length;
 590                } else {
 591                        list_add_tail(&handler->link, &address_handler_list);
 592                        ret = 0;
 593                        break;
 594                }
 595        }
 596
 597        spin_unlock_bh(&address_handler_lock);
 598
 599        return ret;
 600}
 601EXPORT_SYMBOL(fw_core_add_address_handler);
 602
 603/**
 604 * fw_core_remove_address_handler() - unregister an address handler
 605 *
 606 * When fw_core_remove_address_handler() returns, @handler->callback() is
 607 * guaranteed to not run on any CPU anymore.
 608 */
 609void fw_core_remove_address_handler(struct fw_address_handler *handler)
 610{
 611        spin_lock_bh(&address_handler_lock);
 612        list_del(&handler->link);
 613        spin_unlock_bh(&address_handler_lock);
 614}
 615EXPORT_SYMBOL(fw_core_remove_address_handler);
 616
 617struct fw_request {
 618        struct fw_packet response;
 619        u32 request_header[4];
 620        int ack;
 621        u32 length;
 622        u32 data[0];
 623};
 624
 625static void free_response_callback(struct fw_packet *packet,
 626                                   struct fw_card *card, int status)
 627{
 628        struct fw_request *request;
 629
 630        request = container_of(packet, struct fw_request, response);
 631        kfree(request);
 632}
 633
 634int fw_get_response_length(struct fw_request *r)
 635{
 636        int tcode, ext_tcode, data_length;
 637
 638        tcode = HEADER_GET_TCODE(r->request_header[0]);
 639
 640        switch (tcode) {
 641        case TCODE_WRITE_QUADLET_REQUEST:
 642        case TCODE_WRITE_BLOCK_REQUEST:
 643                return 0;
 644
 645        case TCODE_READ_QUADLET_REQUEST:
 646                return 4;
 647
 648        case TCODE_READ_BLOCK_REQUEST:
 649                data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 650                return data_length;
 651
 652        case TCODE_LOCK_REQUEST:
 653                ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
 654                data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 655                switch (ext_tcode) {
 656                case EXTCODE_FETCH_ADD:
 657                case EXTCODE_LITTLE_ADD:
 658                        return data_length;
 659                default:
 660                        return data_length / 2;
 661                }
 662
 663        default:
 664                WARN(1, "wrong tcode %d\n", tcode);
 665                return 0;
 666        }
 667}
 668
 669void fw_fill_response(struct fw_packet *response, u32 *request_header,
 670                      int rcode, void *payload, size_t length)
 671{
 672        int tcode, tlabel, extended_tcode, source, destination;
 673
 674        tcode          = HEADER_GET_TCODE(request_header[0]);
 675        tlabel         = HEADER_GET_TLABEL(request_header[0]);
 676        source         = HEADER_GET_DESTINATION(request_header[0]);
 677        destination    = HEADER_GET_SOURCE(request_header[1]);
 678        extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 679
 680        response->header[0] =
 681                HEADER_RETRY(RETRY_1) |
 682                HEADER_TLABEL(tlabel) |
 683                HEADER_DESTINATION(destination);
 684        response->header[1] =
 685                HEADER_SOURCE(source) |
 686                HEADER_RCODE(rcode);
 687        response->header[2] = 0;
 688
 689        switch (tcode) {
 690        case TCODE_WRITE_QUADLET_REQUEST:
 691        case TCODE_WRITE_BLOCK_REQUEST:
 692                response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 693                response->header_length = 12;
 694                response->payload_length = 0;
 695                break;
 696
 697        case TCODE_READ_QUADLET_REQUEST:
 698                response->header[0] |=
 699                        HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 700                if (payload != NULL)
 701                        response->header[3] = *(u32 *)payload;
 702                else
 703                        response->header[3] = 0;
 704                response->header_length = 16;
 705                response->payload_length = 0;
 706                break;
 707
 708        case TCODE_READ_BLOCK_REQUEST:
 709        case TCODE_LOCK_REQUEST:
 710                response->header[0] |= HEADER_TCODE(tcode + 2);
 711                response->header[3] =
 712                        HEADER_DATA_LENGTH(length) |
 713                        HEADER_EXTENDED_TCODE(extended_tcode);
 714                response->header_length = 16;
 715                response->payload = payload;
 716                response->payload_length = length;
 717                break;
 718
 719        default:
 720                WARN(1, "wrong tcode %d\n", tcode);
 721        }
 722
 723        response->payload_mapped = false;
 724}
 725EXPORT_SYMBOL(fw_fill_response);
 726
 727static u32 compute_split_timeout_timestamp(struct fw_card *card,
 728                                           u32 request_timestamp)
 729{
 730        unsigned int cycles;
 731        u32 timestamp;
 732
 733        cycles = card->split_timeout_cycles;
 734        cycles += request_timestamp & 0x1fff;
 735
 736        timestamp = request_timestamp & ~0x1fff;
 737        timestamp += (cycles / 8000) << 13;
 738        timestamp |= cycles % 8000;
 739
 740        return timestamp;
 741}
 742
 743static struct fw_request *allocate_request(struct fw_card *card,
 744                                           struct fw_packet *p)
 745{
 746        struct fw_request *request;
 747        u32 *data, length;
 748        int request_tcode;
 749
 750        request_tcode = HEADER_GET_TCODE(p->header[0]);
 751        switch (request_tcode) {
 752        case TCODE_WRITE_QUADLET_REQUEST:
 753                data = &p->header[3];
 754                length = 4;
 755                break;
 756
 757        case TCODE_WRITE_BLOCK_REQUEST:
 758        case TCODE_LOCK_REQUEST:
 759                data = p->payload;
 760                length = HEADER_GET_DATA_LENGTH(p->header[3]);
 761                break;
 762
 763        case TCODE_READ_QUADLET_REQUEST:
 764                data = NULL;
 765                length = 4;
 766                break;
 767
 768        case TCODE_READ_BLOCK_REQUEST:
 769                data = NULL;
 770                length = HEADER_GET_DATA_LENGTH(p->header[3]);
 771                break;
 772
 773        default:
 774                fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
 775                         p->header[0], p->header[1], p->header[2]);
 776                return NULL;
 777        }
 778
 779        request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 780        if (request == NULL)
 781                return NULL;
 782
 783        request->response.speed = p->speed;
 784        request->response.timestamp =
 785                        compute_split_timeout_timestamp(card, p->timestamp);
 786        request->response.generation = p->generation;
 787        request->response.ack = 0;
 788        request->response.callback = free_response_callback;
 789        request->ack = p->ack;
 790        request->length = length;
 791        if (data)
 792                memcpy(request->data, data, length);
 793
 794        memcpy(request->request_header, p->header, sizeof(p->header));
 795
 796        return request;
 797}
 798
 799void fw_send_response(struct fw_card *card,
 800                      struct fw_request *request, int rcode)
 801{
 802        if (WARN_ONCE(!request, "invalid for FCP address handlers"))
 803                return;
 804
 805        /* unified transaction or broadcast transaction: don't respond */
 806        if (request->ack != ACK_PENDING ||
 807            HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 808                kfree(request);
 809                return;
 810        }
 811
 812        if (rcode == RCODE_COMPLETE)
 813                fw_fill_response(&request->response, request->request_header,
 814                                 rcode, request->data,
 815                                 fw_get_response_length(request));
 816        else
 817                fw_fill_response(&request->response, request->request_header,
 818                                 rcode, NULL, 0);
 819
 820        card->driver->send_response(card, &request->response);
 821}
 822EXPORT_SYMBOL(fw_send_response);
 823
 824/**
 825 * fw_get_request_speed() - returns speed at which the @request was received
 826 */
 827int fw_get_request_speed(struct fw_request *request)
 828{
 829        return request->response.speed;
 830}
 831EXPORT_SYMBOL(fw_get_request_speed);
 832
 833static void handle_exclusive_region_request(struct fw_card *card,
 834                                            struct fw_packet *p,
 835                                            struct fw_request *request,
 836                                            unsigned long long offset)
 837{
 838        struct fw_address_handler *handler;
 839        int tcode, destination, source;
 840
 841        destination = HEADER_GET_DESTINATION(p->header[0]);
 842        source      = HEADER_GET_SOURCE(p->header[1]);
 843        tcode       = HEADER_GET_TCODE(p->header[0]);
 844        if (tcode == TCODE_LOCK_REQUEST)
 845                tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 846
 847        spin_lock_bh(&address_handler_lock);
 848        handler = lookup_enclosing_address_handler(&address_handler_list,
 849                                                   offset, request->length);
 850        if (handler)
 851                handler->address_callback(card, request,
 852                                          tcode, destination, source,
 853                                          p->generation, offset,
 854                                          request->data, request->length,
 855                                          handler->callback_data);
 856        spin_unlock_bh(&address_handler_lock);
 857
 858        if (!handler)
 859                fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 860}
 861
 862static void handle_fcp_region_request(struct fw_card *card,
 863                                      struct fw_packet *p,
 864                                      struct fw_request *request,
 865                                      unsigned long long offset)
 866{
 867        struct fw_address_handler *handler;
 868        int tcode, destination, source;
 869
 870        if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 871             offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
 872            request->length > 0x200) {
 873                fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 874
 875                return;
 876        }
 877
 878        tcode       = HEADER_GET_TCODE(p->header[0]);
 879        destination = HEADER_GET_DESTINATION(p->header[0]);
 880        source      = HEADER_GET_SOURCE(p->header[1]);
 881
 882        if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
 883            tcode != TCODE_WRITE_BLOCK_REQUEST) {
 884                fw_send_response(card, request, RCODE_TYPE_ERROR);
 885
 886                return;
 887        }
 888
 889        spin_lock_bh(&address_handler_lock);
 890        list_for_each_entry(handler, &address_handler_list, link) {
 891                if (is_enclosing_handler(handler, offset, request->length))
 892                        handler->address_callback(card, NULL, tcode,
 893                                                  destination, source,
 894                                                  p->generation, offset,
 895                                                  request->data,
 896                                                  request->length,
 897                                                  handler->callback_data);
 898        }
 899        spin_unlock_bh(&address_handler_lock);
 900
 901        fw_send_response(card, request, RCODE_COMPLETE);
 902}
 903
 904void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
 905{
 906        struct fw_request *request;
 907        unsigned long long offset;
 908
 909        if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
 910                return;
 911
 912        if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
 913                fw_cdev_handle_phy_packet(card, p);
 914                return;
 915        }
 916
 917        request = allocate_request(card, p);
 918        if (request == NULL) {
 919                /* FIXME: send statically allocated busy packet. */
 920                return;
 921        }
 922
 923        offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
 924                p->header[2];
 925
 926        if (!is_in_fcp_region(offset, request->length))
 927                handle_exclusive_region_request(card, p, request, offset);
 928        else
 929                handle_fcp_region_request(card, p, request, offset);
 930
 931}
 932EXPORT_SYMBOL(fw_core_handle_request);
 933
 934void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
 935{
 936        struct fw_transaction *t;
 937        unsigned long flags;
 938        u32 *data;
 939        size_t data_length;
 940        int tcode, tlabel, source, rcode;
 941
 942        tcode   = HEADER_GET_TCODE(p->header[0]);
 943        tlabel  = HEADER_GET_TLABEL(p->header[0]);
 944        source  = HEADER_GET_SOURCE(p->header[1]);
 945        rcode   = HEADER_GET_RCODE(p->header[1]);
 946
 947        spin_lock_irqsave(&card->lock, flags);
 948        list_for_each_entry(t, &card->transaction_list, link) {
 949                if (t->node_id == source && t->tlabel == tlabel) {
 950                        if (!try_cancel_split_timeout(t)) {
 951                                spin_unlock_irqrestore(&card->lock, flags);
 952                                goto timed_out;
 953                        }
 954                        list_del_init(&t->link);
 955                        card->tlabel_mask &= ~(1ULL << t->tlabel);
 956                        break;
 957                }
 958        }
 959        spin_unlock_irqrestore(&card->lock, flags);
 960
 961        if (&t->link == &card->transaction_list) {
 962 timed_out:
 963                fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
 964                          source, tlabel);
 965                return;
 966        }
 967
 968        /*
 969         * FIXME: sanity check packet, is length correct, does tcodes
 970         * and addresses match.
 971         */
 972
 973        switch (tcode) {
 974        case TCODE_READ_QUADLET_RESPONSE:
 975                data = (u32 *) &p->header[3];
 976                data_length = 4;
 977                break;
 978
 979        case TCODE_WRITE_RESPONSE:
 980                data = NULL;
 981                data_length = 0;
 982                break;
 983
 984        case TCODE_READ_BLOCK_RESPONSE:
 985        case TCODE_LOCK_RESPONSE:
 986                data = p->payload;
 987                data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
 988                break;
 989
 990        default:
 991                /* Should never happen, this is just to shut up gcc. */
 992                data = NULL;
 993                data_length = 0;
 994                break;
 995        }
 996
 997        /*
 998         * The response handler may be executed while the request handler
 999         * is still pending.  Cancel the request handler.
1000         */
1001        card->driver->cancel_packet(card, &t->packet);
1002
1003        t->callback(card, rcode, data, data_length, t->callback_data);
1004}
1005EXPORT_SYMBOL(fw_core_handle_response);
1006
1007/**
1008 * fw_rcode_string - convert a firewire result code to an error description
1009 * @rcode: the result code
1010 */
1011const char *fw_rcode_string(int rcode)
1012{
1013        static const char *const names[] = {
1014                [RCODE_COMPLETE]       = "no error",
1015                [RCODE_CONFLICT_ERROR] = "conflict error",
1016                [RCODE_DATA_ERROR]     = "data error",
1017                [RCODE_TYPE_ERROR]     = "type error",
1018                [RCODE_ADDRESS_ERROR]  = "address error",
1019                [RCODE_SEND_ERROR]     = "send error",
1020                [RCODE_CANCELLED]      = "timeout",
1021                [RCODE_BUSY]           = "busy",
1022                [RCODE_GENERATION]     = "bus reset",
1023                [RCODE_NO_ACK]         = "no ack",
1024        };
1025
1026        if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1027                return names[rcode];
1028        else
1029                return "unknown";
1030}
1031EXPORT_SYMBOL(fw_rcode_string);
1032
1033static const struct fw_address_region topology_map_region =
1034        { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1035          .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1036
1037static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1038                int tcode, int destination, int source, int generation,
1039                unsigned long long offset, void *payload, size_t length,
1040                void *callback_data)
1041{
1042        int start;
1043
1044        if (!TCODE_IS_READ_REQUEST(tcode)) {
1045                fw_send_response(card, request, RCODE_TYPE_ERROR);
1046                return;
1047        }
1048
1049        if ((offset & 3) > 0 || (length & 3) > 0) {
1050                fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1051                return;
1052        }
1053
1054        start = (offset - topology_map_region.start) / 4;
1055        memcpy(payload, &card->topology_map[start], length);
1056
1057        fw_send_response(card, request, RCODE_COMPLETE);
1058}
1059
1060static struct fw_address_handler topology_map = {
1061        .length                 = 0x400,
1062        .address_callback       = handle_topology_map,
1063};
1064
1065static const struct fw_address_region registers_region =
1066        { .start = CSR_REGISTER_BASE,
1067          .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1068
1069static void update_split_timeout(struct fw_card *card)
1070{
1071        unsigned int cycles;
1072
1073        cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1074
1075        /* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1076        cycles = clamp(cycles, 800u, 3u * 8000u);
1077
1078        card->split_timeout_cycles = cycles;
1079        card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1080}
1081
1082static void handle_registers(struct fw_card *card, struct fw_request *request,
1083                int tcode, int destination, int source, int generation,
1084                unsigned long long offset, void *payload, size_t length,
1085                void *callback_data)
1086{
1087        int reg = offset & ~CSR_REGISTER_BASE;
1088        __be32 *data = payload;
1089        int rcode = RCODE_COMPLETE;
1090        unsigned long flags;
1091
1092        switch (reg) {
1093        case CSR_PRIORITY_BUDGET:
1094                if (!card->priority_budget_implemented) {
1095                        rcode = RCODE_ADDRESS_ERROR;
1096                        break;
1097                }
1098                /* else fall through */
1099
1100        case CSR_NODE_IDS:
1101                /*
1102                 * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1103                 * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1104                 */
1105                /* fall through */
1106
1107        case CSR_STATE_CLEAR:
1108        case CSR_STATE_SET:
1109        case CSR_CYCLE_TIME:
1110        case CSR_BUS_TIME:
1111        case CSR_BUSY_TIMEOUT:
1112                if (tcode == TCODE_READ_QUADLET_REQUEST)
1113                        *data = cpu_to_be32(card->driver->read_csr(card, reg));
1114                else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1115                        card->driver->write_csr(card, reg, be32_to_cpu(*data));
1116                else
1117                        rcode = RCODE_TYPE_ERROR;
1118                break;
1119
1120        case CSR_RESET_START:
1121                if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1122                        card->driver->write_csr(card, CSR_STATE_CLEAR,
1123                                                CSR_STATE_BIT_ABDICATE);
1124                else
1125                        rcode = RCODE_TYPE_ERROR;
1126                break;
1127
1128        case CSR_SPLIT_TIMEOUT_HI:
1129                if (tcode == TCODE_READ_QUADLET_REQUEST) {
1130                        *data = cpu_to_be32(card->split_timeout_hi);
1131                } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1132                        spin_lock_irqsave(&card->lock, flags);
1133                        card->split_timeout_hi = be32_to_cpu(*data) & 7;
1134                        update_split_timeout(card);
1135                        spin_unlock_irqrestore(&card->lock, flags);
1136                } else {
1137                        rcode = RCODE_TYPE_ERROR;
1138                }
1139                break;
1140
1141        case CSR_SPLIT_TIMEOUT_LO:
1142                if (tcode == TCODE_READ_QUADLET_REQUEST) {
1143                        *data = cpu_to_be32(card->split_timeout_lo);
1144                } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1145                        spin_lock_irqsave(&card->lock, flags);
1146                        card->split_timeout_lo =
1147                                        be32_to_cpu(*data) & 0xfff80000;
1148                        update_split_timeout(card);
1149                        spin_unlock_irqrestore(&card->lock, flags);
1150                } else {
1151                        rcode = RCODE_TYPE_ERROR;
1152                }
1153                break;
1154
1155        case CSR_MAINT_UTILITY:
1156                if (tcode == TCODE_READ_QUADLET_REQUEST)
1157                        *data = card->maint_utility_register;
1158                else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1159                        card->maint_utility_register = *data;
1160                else
1161                        rcode = RCODE_TYPE_ERROR;
1162                break;
1163
1164        case CSR_BROADCAST_CHANNEL:
1165                if (tcode == TCODE_READ_QUADLET_REQUEST)
1166                        *data = cpu_to_be32(card->broadcast_channel);
1167                else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1168                        card->broadcast_channel =
1169                            (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1170                            BROADCAST_CHANNEL_INITIAL;
1171                else
1172                        rcode = RCODE_TYPE_ERROR;
1173                break;
1174
1175        case CSR_BUS_MANAGER_ID:
1176        case CSR_BANDWIDTH_AVAILABLE:
1177        case CSR_CHANNELS_AVAILABLE_HI:
1178        case CSR_CHANNELS_AVAILABLE_LO:
1179                /*
1180                 * FIXME: these are handled by the OHCI hardware and
1181                 * the stack never sees these request. If we add
1182                 * support for a new type of controller that doesn't
1183                 * handle this in hardware we need to deal with these
1184                 * transactions.
1185                 */
1186                BUG();
1187                break;
1188
1189        default:
1190                rcode = RCODE_ADDRESS_ERROR;
1191                break;
1192        }
1193
1194        fw_send_response(card, request, rcode);
1195}
1196
1197static struct fw_address_handler registers = {
1198        .length                 = 0x400,
1199        .address_callback       = handle_registers,
1200};
1201
1202static void handle_low_memory(struct fw_card *card, struct fw_request *request,
1203                int tcode, int destination, int source, int generation,
1204                unsigned long long offset, void *payload, size_t length,
1205                void *callback_data)
1206{
1207        /*
1208         * This catches requests not handled by the physical DMA unit,
1209         * i.e., wrong transaction types or unauthorized source nodes.
1210         */
1211        fw_send_response(card, request, RCODE_TYPE_ERROR);
1212}
1213
1214static struct fw_address_handler low_memory = {
1215        .length                 = 0x000100000000ULL,
1216        .address_callback       = handle_low_memory,
1217};
1218
1219MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1220MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1221MODULE_LICENSE("GPL");
1222
1223static const u32 vendor_textual_descriptor[] = {
1224        /* textual descriptor leaf () */
1225        0x00060000,
1226        0x00000000,
1227        0x00000000,
1228        0x4c696e75,             /* L i n u */
1229        0x78204669,             /* x   F i */
1230        0x72657769,             /* r e w i */
1231        0x72650000,             /* r e     */
1232};
1233
1234static const u32 model_textual_descriptor[] = {
1235        /* model descriptor leaf () */
1236        0x00030000,
1237        0x00000000,
1238        0x00000000,
1239        0x4a756a75,             /* J u j u */
1240};
1241
1242static struct fw_descriptor vendor_id_descriptor = {
1243        .length = ARRAY_SIZE(vendor_textual_descriptor),
1244        .immediate = 0x03d00d1e,
1245        .key = 0x81000000,
1246        .data = vendor_textual_descriptor,
1247};
1248
1249static struct fw_descriptor model_id_descriptor = {
1250        .length = ARRAY_SIZE(model_textual_descriptor),
1251        .immediate = 0x17000001,
1252        .key = 0x81000000,
1253        .data = model_textual_descriptor,
1254};
1255
1256static int __init fw_core_init(void)
1257{
1258        int ret;
1259
1260        fw_workqueue = alloc_workqueue("firewire",
1261                                       WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0);
1262        if (!fw_workqueue)
1263                return -ENOMEM;
1264
1265        ret = bus_register(&fw_bus_type);
1266        if (ret < 0) {
1267                destroy_workqueue(fw_workqueue);
1268                return ret;
1269        }
1270
1271        fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1272        if (fw_cdev_major < 0) {
1273                bus_unregister(&fw_bus_type);
1274                destroy_workqueue(fw_workqueue);
1275                return fw_cdev_major;
1276        }
1277
1278        fw_core_add_address_handler(&topology_map, &topology_map_region);
1279        fw_core_add_address_handler(&registers, &registers_region);
1280        fw_core_add_address_handler(&low_memory, &low_memory_region);
1281        fw_core_add_descriptor(&vendor_id_descriptor);
1282        fw_core_add_descriptor(&model_id_descriptor);
1283
1284        return 0;
1285}
1286
1287static void __exit fw_core_cleanup(void)
1288{
1289        unregister_chrdev(fw_cdev_major, "firewire");
1290        bus_unregister(&fw_bus_type);
1291        destroy_workqueue(fw_workqueue);
1292        idr_destroy(&fw_device_idr);
1293}
1294
1295module_init(fw_core_init);
1296module_exit(fw_core_cleanup);
1297
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.