git.oblomov.eu Git - linux-2.6/blob - drivers/ieee1394/ieee1394_transactions.c

   1 /*
   2  * IEEE 1394 for Linux
   3  *
   4  * Transaction support.
   5  *
   6  * Copyright (C) 1999 Andreas E. Bombe
   7  *
   8  * This code is licensed under the GPL.  See the file COPYING in the root
   9  * directory of the kernel sources for details.
  10  */
  11
  12 #include <linux/bitops.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/wait.h>
  15
  16 #include <asm/bug.h>
  17 #include <asm/errno.h>
  18
  19 #include "ieee1394.h"
  20 #include "ieee1394_types.h"
  21 #include "hosts.h"
  22 #include "ieee1394_core.h"
  23 #include "ieee1394_transactions.h"
  24
  25 #define PREP_ASYNC_HEAD_ADDRESS(tc) \
  26         packet->tcode = tc; \
  27         packet->header[0] = (packet->node_id << 16) | (packet->tlabel << 10) \
  28                 | (1 << 8) | (tc << 4); \
  29         packet->header[1] = (packet->host->node_id << 16) | (addr >> 32); \
  30         packet->header[2] = addr & 0xffffffff
  31
  32 #ifndef HPSB_DEBUG_TLABELS
  33 static
  34 #endif
  35 spinlock_t hpsb_tlabel_lock = SPIN_LOCK_UNLOCKED;
  36
  37 static DECLARE_WAIT_QUEUE_HEAD(tlabel_wq);
  38
  39 static void fill_async_readquad(struct hpsb_packet *packet, u64 addr)
  40 {
  41         PREP_ASYNC_HEAD_ADDRESS(TCODE_READQ);
  42         packet->header_size = 12;
  43         packet->data_size = 0;
  44         packet->expect_response = 1;
  45 }
  46
  47 static void fill_async_readblock(struct hpsb_packet *packet, u64 addr,
  48                                  int length)
  49 {
  50         PREP_ASYNC_HEAD_ADDRESS(TCODE_READB);
  51         packet->header[3] = length << 16;
  52         packet->header_size = 16;
  53         packet->data_size = 0;
  54         packet->expect_response = 1;
  55 }
  56
  57 static void fill_async_writequad(struct hpsb_packet *packet, u64 addr,
  58                                  quadlet_t data)
  59 {
  60         PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEQ);
  61         packet->header[3] = data;
  62         packet->header_size = 16;
  63         packet->data_size = 0;
  64         packet->expect_response = 1;
  65 }
  66
  67 static void fill_async_writeblock(struct hpsb_packet *packet, u64 addr,
  68                                   int length)
  69 {
  70         PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEB);
  71         packet->header[3] = length << 16;
  72         packet->header_size = 16;
  73         packet->expect_response = 1;
  74         packet->data_size = length + (length % 4 ? 4 - (length % 4) : 0);
  75 }
  76
  77 static void fill_async_lock(struct hpsb_packet *packet, u64 addr, int extcode,
  78                             int length)
  79 {
  80         PREP_ASYNC_HEAD_ADDRESS(TCODE_LOCK_REQUEST);
  81         packet->header[3] = (length << 16) | extcode;
  82         packet->header_size = 16;
  83         packet->data_size = length;
  84         packet->expect_response = 1;
  85 }
  86
  87 static void fill_iso_packet(struct hpsb_packet *packet, int length, int channel,
  88                             int tag, int sync)
  89 {
  90         packet->header[0] = (length << 16) | (tag << 14) | (channel << 8)
  91             | (TCODE_ISO_DATA << 4) | sync;
  92
  93         packet->header_size = 4;
  94         packet->data_size = length;
  95         packet->type = hpsb_iso;
  96         packet->tcode = TCODE_ISO_DATA;
  97 }
  98
  99 static void fill_phy_packet(struct hpsb_packet *packet, quadlet_t data)
 100 {
 101         packet->header[0] = data;
 102         packet->header[1] = ~data;
 103         packet->header_size = 8;
 104         packet->data_size = 0;
 105         packet->expect_response = 0;
 106         packet->type = hpsb_raw;        /* No CRC added */
 107         packet->speed_code = IEEE1394_SPEED_100;        /* Force speed to be 100Mbps */
 108 }
 109
 110 static void fill_async_stream_packet(struct hpsb_packet *packet, int length,
 111                                      int channel, int tag, int sync)
 112 {
 113         packet->header[0] = (length << 16) | (tag << 14) | (channel << 8)
 114             | (TCODE_STREAM_DATA << 4) | sync;
 115
 116         packet->header_size = 4;
 117         packet->data_size = length;
 118         packet->type = hpsb_async;
 119         packet->tcode = TCODE_ISO_DATA;
 120 }
 121
 122 /* same as hpsb_get_tlabel, except that it returns immediately */
 123 static int hpsb_get_tlabel_atomic(struct hpsb_packet *packet)
 124 {
 125         unsigned long flags, *tp;
 126         u8 *next;
 127         int tlabel, n = NODEID_TO_NODE(packet->node_id);
 128
 129         /* Broadcast transactions are complete once the request has been sent.
 130          * Use the same transaction label for all broadcast transactions. */
 131         if (unlikely(n == ALL_NODES)) {
 132                 packet->tlabel = 0;
 133                 return 0;
 134         }
 135         tp = packet->host->tl_pool[n].map;
 136         next = &packet->host->next_tl[n];
 137
 138         spin_lock_irqsave(&hpsb_tlabel_lock, flags);
 139         tlabel = find_next_zero_bit(tp, 64, *next);
 140         if (tlabel > 63)
 141                 tlabel = find_first_zero_bit(tp, 64);
 142         if (tlabel > 63) {
 143                 spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
 144                 return -EAGAIN;
 145         }
 146         __set_bit(tlabel, tp);
 147         *next = (tlabel + 1) & 63;
 148         spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
 149
 150         packet->tlabel = tlabel;
 151         return 0;
 152 }
 153
 154 /**
 155  * hpsb_get_tlabel - allocate a transaction label
 156  * @packet: the packet whose tlabel and tl_pool we set
 157  *
 158  * Every asynchronous transaction on the 1394 bus needs a transaction
 159  * label to match the response to the request.  This label has to be
 160  * different from any other transaction label in an outstanding request to
 161  * the same node to make matching possible without ambiguity.
 162  *
 163  * There are 64 different tlabels, so an allocated tlabel has to be freed
 164  * with hpsb_free_tlabel() after the transaction is complete (unless it's
 165  * reused again for the same target node).
 166  *
 167  * Return value: Zero on success, otherwise non-zero. A non-zero return
 168  * generally means there are no available tlabels. If this is called out
 169  * of interrupt or atomic context, then it will sleep until can return a
 170  * tlabel or a signal is received.
 171  */
 172 int hpsb_get_tlabel(struct hpsb_packet *packet)
 173 {
 174         if (irqs_disabled() || in_atomic())
 175                 return hpsb_get_tlabel_atomic(packet);
 176
 177         /* NB: The macro wait_event_interruptible() is called with a condition
 178          * argument with side effect.  This is only possible because the side
 179          * effect does not occur until the condition became true, and
 180          * wait_event_interruptible() won't evaluate the condition again after
 181          * that. */
 182         return wait_event_interruptible(tlabel_wq,
 183                                         !hpsb_get_tlabel_atomic(packet));
 184 }
 185
 186 /**
 187  * hpsb_free_tlabel - free an allocated transaction label
 188  * @packet: packet whose tlabel and tl_pool needs to be cleared
 189  *
 190  * Frees the transaction label allocated with hpsb_get_tlabel().  The
 191  * tlabel has to be freed after the transaction is complete (i.e. response
 192  * was received for a split transaction or packet was sent for a unified
 193  * transaction).
 194  *
 195  * A tlabel must not be freed twice.
 196  */
 197 void hpsb_free_tlabel(struct hpsb_packet *packet)
 198 {
 199         unsigned long flags, *tp;
 200         int tlabel, n = NODEID_TO_NODE(packet->node_id);
 201
 202         if (unlikely(n == ALL_NODES))
 203                 return;
 204         tp = packet->host->tl_pool[n].map;
 205         tlabel = packet->tlabel;
 206         BUG_ON(tlabel > 63 || tlabel < 0);
 207
 208         spin_lock_irqsave(&hpsb_tlabel_lock, flags);
 209         BUG_ON(!__test_and_clear_bit(tlabel, tp));
 210         spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
 211
 212         wake_up_interruptible(&tlabel_wq);
 213 }
 214
 215 int hpsb_packet_success(struct hpsb_packet *packet)
 216 {
 217         switch (packet->ack_code) {
 218         case ACK_PENDING:
 219                 switch ((packet->header[1] >> 12) & 0xf) {
 220                 case RCODE_COMPLETE:
 221                         return 0;
 222                 case RCODE_CONFLICT_ERROR:
 223                         return -EAGAIN;
 224                 case RCODE_DATA_ERROR:
 225                         return -EREMOTEIO;
 226                 case RCODE_TYPE_ERROR:
 227                         return -EACCES;
 228                 case RCODE_ADDRESS_ERROR:
 229                         return -EINVAL;
 230                 default:
 231                         HPSB_ERR("received reserved rcode %d from node %d",
 232                                  (packet->header[1] >> 12) & 0xf,
 233                                  packet->node_id);
 234                         return -EAGAIN;
 235                 }
 236                 BUG();
 237
 238         case ACK_BUSY_X:
 239         case ACK_BUSY_A:
 240         case ACK_BUSY_B:
 241                 return -EBUSY;
 242
 243         case ACK_TYPE_ERROR:
 244                 return -EACCES;
 245
 246         case ACK_COMPLETE:
 247                 if (packet->tcode == TCODE_WRITEQ
 248                     || packet->tcode == TCODE_WRITEB) {
 249                         return 0;
 250                 } else {
 251                         HPSB_ERR("impossible ack_complete from node %d "
 252                                  "(tcode %d)", packet->node_id, packet->tcode);
 253                         return -EAGAIN;
 254                 }
 255
 256         case ACK_DATA_ERROR:
 257                 if (packet->tcode == TCODE_WRITEB
 258                     || packet->tcode == TCODE_LOCK_REQUEST) {
 259                         return -EAGAIN;
 260                 } else {
 261                         HPSB_ERR("impossible ack_data_error from node %d "
 262                                  "(tcode %d)", packet->node_id, packet->tcode);
 263                         return -EAGAIN;
 264                 }
 265
 266         case ACK_ADDRESS_ERROR:
 267                 return -EINVAL;
 268
 269         case ACK_TARDY:
 270         case ACK_CONFLICT_ERROR:
 271         case ACKX_NONE:
 272         case ACKX_SEND_ERROR:
 273         case ACKX_ABORTED:
 274         case ACKX_TIMEOUT:
 275                 /* error while sending */
 276                 return -EAGAIN;
 277
 278         default:
 279                 HPSB_ERR("got invalid ack %d from node %d (tcode %d)",
 280                          packet->ack_code, packet->node_id, packet->tcode);
 281                 return -EAGAIN;
 282         }
 283         BUG();
 284 }
 285
 286 struct hpsb_packet *hpsb_make_readpacket(struct hpsb_host *host, nodeid_t node,
 287                                          u64 addr, size_t length)
 288 {
 289         struct hpsb_packet *packet;
 290
 291         if (length == 0)
 292                 return NULL;
 293
 294         packet = hpsb_alloc_packet(length);
 295         if (!packet)
 296                 return NULL;
 297
 298         packet->host = host;
 299         packet->node_id = node;
 300
 301         if (hpsb_get_tlabel(packet)) {
 302                 hpsb_free_packet(packet);
 303                 return NULL;
 304         }
 305
 306         if (length == 4)
 307                 fill_async_readquad(packet, addr);
 308         else
 309                 fill_async_readblock(packet, addr, length);
 310
 311         return packet;
 312 }
 313
 314 struct hpsb_packet *hpsb_make_writepacket(struct hpsb_host *host, nodeid_t node,
 315                                           u64 addr, quadlet_t * buffer,
 316                                           size_t length)
 317 {
 318         struct hpsb_packet *packet;
 319
 320         if (length == 0)
 321                 return NULL;
 322
 323         packet = hpsb_alloc_packet(length);
 324         if (!packet)
 325                 return NULL;
 326
 327         if (length % 4) {       /* zero padding bytes */
 328                 packet->data[length >> 2] = 0;
 329         }
 330         packet->host = host;
 331         packet->node_id = node;
 332
 333         if (hpsb_get_tlabel(packet)) {
 334                 hpsb_free_packet(packet);
 335                 return NULL;
 336         }
 337
 338         if (length == 4) {
 339                 fill_async_writequad(packet, addr, buffer ? *buffer : 0);
 340         } else {
 341                 fill_async_writeblock(packet, addr, length);
 342                 if (buffer)
 343                         memcpy(packet->data, buffer, length);
 344         }
 345
 346         return packet;
 347 }
 348
 349 struct hpsb_packet *hpsb_make_streampacket(struct hpsb_host *host, u8 * buffer,
 350                                            int length, int channel, int tag,
 351                                            int sync)
 352 {
 353         struct hpsb_packet *packet;
 354
 355         if (length == 0)
 356                 return NULL;
 357
 358         packet = hpsb_alloc_packet(length);
 359         if (!packet)
 360                 return NULL;
 361
 362         if (length % 4) {       /* zero padding bytes */
 363                 packet->data[length >> 2] = 0;
 364         }
 365         packet->host = host;
 366
 367         if (hpsb_get_tlabel(packet)) {
 368                 hpsb_free_packet(packet);
 369                 return NULL;
 370         }
 371
 372         fill_async_stream_packet(packet, length, channel, tag, sync);
 373         if (buffer)
 374                 memcpy(packet->data, buffer, length);
 375
 376         return packet;
 377 }
 378
 379 struct hpsb_packet *hpsb_make_lockpacket(struct hpsb_host *host, nodeid_t node,
 380                                          u64 addr, int extcode,
 381                                          quadlet_t * data, quadlet_t arg)
 382 {
 383         struct hpsb_packet *p;
 384         u32 length;
 385
 386         p = hpsb_alloc_packet(8);
 387         if (!p)
 388                 return NULL;
 389
 390         p->host = host;
 391         p->node_id = node;
 392         if (hpsb_get_tlabel(p)) {
 393                 hpsb_free_packet(p);
 394                 return NULL;
 395         }
 396
 397         switch (extcode) {
 398         case EXTCODE_FETCH_ADD:
 399         case EXTCODE_LITTLE_ADD:
 400                 length = 4;
 401                 if (data)
 402                         p->data[0] = *data;
 403                 break;
 404         default:
 405                 length = 8;
 406                 if (data) {
 407                         p->data[0] = arg;
 408                         p->data[1] = *data;
 409                 }
 410                 break;
 411         }
 412         fill_async_lock(p, addr, extcode, length);
 413
 414         return p;
 415 }
 416
 417 struct hpsb_packet *hpsb_make_lock64packet(struct hpsb_host *host,
 418                                            nodeid_t node, u64 addr, int extcode,
 419                                            octlet_t * data, octlet_t arg)
 420 {
 421         struct hpsb_packet *p;
 422         u32 length;
 423
 424         p = hpsb_alloc_packet(16);
 425         if (!p)
 426                 return NULL;
 427
 428         p->host = host;
 429         p->node_id = node;
 430         if (hpsb_get_tlabel(p)) {
 431                 hpsb_free_packet(p);
 432                 return NULL;
 433         }
 434
 435         switch (extcode) {
 436         case EXTCODE_FETCH_ADD:
 437         case EXTCODE_LITTLE_ADD:
 438                 length = 8;
 439                 if (data) {
 440                         p->data[0] = *data >> 32;
 441                         p->data[1] = *data & 0xffffffff;
 442                 }
 443                 break;
 444         default:
 445                 length = 16;
 446                 if (data) {
 447                         p->data[0] = arg >> 32;
 448                         p->data[1] = arg & 0xffffffff;
 449                         p->data[2] = *data >> 32;
 450                         p->data[3] = *data & 0xffffffff;
 451                 }
 452                 break;
 453         }
 454         fill_async_lock(p, addr, extcode, length);
 455
 456         return p;
 457 }
 458
 459 struct hpsb_packet *hpsb_make_phypacket(struct hpsb_host *host, quadlet_t data)
 460 {
 461         struct hpsb_packet *p;
 462
 463         p = hpsb_alloc_packet(0);
 464         if (!p)
 465                 return NULL;
 466
 467         p->host = host;
 468         fill_phy_packet(p, data);
 469
 470         return p;
 471 }
 472
 473 struct hpsb_packet *hpsb_make_isopacket(struct hpsb_host *host,
 474                                         int length, int channel,
 475                                         int tag, int sync)
 476 {
 477         struct hpsb_packet *p;
 478
 479         p = hpsb_alloc_packet(length);
 480         if (!p)
 481                 return NULL;
 482
 483         p->host = host;
 484         fill_iso_packet(p, length, channel, tag, sync);
 485
 486         p->generation = get_hpsb_generation(host);
 487
 488         return p;
 489 }
 490
 491 /*
 492  * FIXME - these functions should probably read from / write to user space to
 493  * avoid in kernel buffers for user space callers
 494  */
 495
 496 int hpsb_read(struct hpsb_host *host, nodeid_t node, unsigned int generation,
 497               u64 addr, quadlet_t * buffer, size_t length)
 498 {
 499         struct hpsb_packet *packet;
 500         int retval = 0;
 501
 502         if (length == 0)
 503                 return -EINVAL;
 504
 505         BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
 506
 507         packet = hpsb_make_readpacket(host, node, addr, length);
 508
 509         if (!packet) {
 510                 return -ENOMEM;
 511         }
 512
 513         packet->generation = generation;
 514         retval = hpsb_send_packet_and_wait(packet);
 515         if (retval < 0)
 516                 goto hpsb_read_fail;
 517
 518         retval = hpsb_packet_success(packet);
 519
 520         if (retval == 0) {
 521                 if (length == 4) {
 522                         *buffer = packet->header[3];
 523                 } else {
 524                         memcpy(buffer, packet->data, length);
 525                 }
 526         }
 527
 528       hpsb_read_fail:
 529         hpsb_free_tlabel(packet);
 530         hpsb_free_packet(packet);
 531
 532         return retval;
 533 }
 534
 535 int hpsb_write(struct hpsb_host *host, nodeid_t node, unsigned int generation,
 536                u64 addr, quadlet_t * buffer, size_t length)
 537 {
 538         struct hpsb_packet *packet;
 539         int retval;
 540
 541         if (length == 0)
 542                 return -EINVAL;
 543
 544         BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
 545
 546         packet = hpsb_make_writepacket(host, node, addr, buffer, length);
 547
 548         if (!packet)
 549                 return -ENOMEM;
 550
 551         packet->generation = generation;
 552         retval = hpsb_send_packet_and_wait(packet);
 553         if (retval < 0)
 554                 goto hpsb_write_fail;
 555
 556         retval = hpsb_packet_success(packet);
 557
 558       hpsb_write_fail:
 559         hpsb_free_tlabel(packet);
 560         hpsb_free_packet(packet);
 561
 562         return retval;
 563 }
 564
 565 #if 0
 566
 567 int hpsb_lock(struct hpsb_host *host, nodeid_t node, unsigned int generation,
 568               u64 addr, int extcode, quadlet_t * data, quadlet_t arg)
 569 {
 570         struct hpsb_packet *packet;
 571         int retval = 0;
 572
 573         BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet
 574
 575         packet = hpsb_make_lockpacket(host, node, addr, extcode, data, arg);
 576         if (!packet)
 577                 return -ENOMEM;
 578
 579         packet->generation = generation;
 580         retval = hpsb_send_packet_and_wait(packet);
 581         if (retval < 0)
 582                 goto hpsb_lock_fail;
 583
 584         retval = hpsb_packet_success(packet);
 585
 586         if (retval == 0) {
 587                 *data = packet->data[0];
 588         }
 589
 590       hpsb_lock_fail:
 591         hpsb_free_tlabel(packet);
 592         hpsb_free_packet(packet);
 593
 594         return retval;
 595 }
 596
 597 int hpsb_send_gasp(struct hpsb_host *host, int channel, unsigned int generation,
 598                    quadlet_t * buffer, size_t length, u32 specifier_id,
 599                    unsigned int version)
 600 {
 601         struct hpsb_packet *packet;
 602         int retval = 0;
 603         u16 specifier_id_hi = (specifier_id & 0x00ffff00) >> 8;
 604         u8 specifier_id_lo = specifier_id & 0xff;
 605
 606         HPSB_VERBOSE("Send GASP: channel = %d, length = %Zd", channel, length);
 607
 608         length += 8;
 609
 610         packet = hpsb_make_streampacket(host, NULL, length, channel, 3, 0);
 611         if (!packet)
 612                 return -ENOMEM;
 613
 614         packet->data[0] = cpu_to_be32((host->node_id << 16) | specifier_id_hi);
 615         packet->data[1] =
 616             cpu_to_be32((specifier_id_lo << 24) | (version & 0x00ffffff));
 617
 618         memcpy(&(packet->data[2]), buffer, length - 8);
 619
 620         packet->generation = generation;
 621
 622         packet->no_waiter = 1;
 623
 624         retval = hpsb_send_packet(packet);
 625         if (retval < 0)
 626                 hpsb_free_packet(packet);
 627
 628         return retval;
 629 }
 630
 631 #endif                          /*  0  */