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