software/SCSI2SD/src/disk.c

   1 //      Copyright (C) 2013 Michael McMaster <michael@codesrc.com>\r
   2 //      Copyright (C) 2014 Doug Brown <doug@downtowndougbrown.com>\r
   3 //\r
   4 //      This file is part of SCSI2SD.\r
   5 //\r
   6 //      SCSI2SD is free software: you can redistribute it and/or modify\r
   7 //      it under the terms of the GNU General Public License as published by\r
   8 //      the Free Software Foundation, either version 3 of the License, or\r
   9 //      (at your option) any later version.\r
  10 //\r
  11 //      SCSI2SD is distributed in the hope that it will be useful,\r
  12 //      but WITHOUT ANY WARRANTY; without even the implied warranty of\r
  13 //      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\r
  14 //      GNU General Public License for more details.\r
  15 //\r
  16 //      You should have received a copy of the GNU General Public License\r
  17 //      along with SCSI2SD.  If not, see <http://www.gnu.org/licenses/>.\r
  18 #pragma GCC push_options\r
  19 #pragma GCC optimize("-flto")\r
  20 \r
  21 #include "device.h"\r
  22 #include "scsi.h"\r
  23 #include "scsiPhy.h"\r
  24 #include "config.h"\r
  25 #include "debug.h"\r
  26 #include "debug.h"\r
  27 #include "disk.h"\r
  28 #include "sd.h"\r
  29 #include "time.h"\r
  30 \r
  31 #include <string.h>\r
  32 \r
  33 // Global\r
  34 BlockDevice blockDev;\r
  35 Transfer transfer;\r
  36 \r
  37 static int doSdInit()\r
  38 {\r
  39         int result = 0;\r
  40         if (blockDev.state & DISK_PRESENT)\r
  41         {\r
  42                 result = sdInit();\r
  43 \r
  44                 if (result)\r
  45                 {\r
  46                         blockDev.state = blockDev.state | DISK_INITIALISED;\r
  47                 }\r
  48         }\r
  49         return result;\r
  50 }\r
  51 \r
  52 // Callback once all data has been read in the data out phase.\r
  53 static void doFormatUnitComplete(void)\r
  54 {\r
  55         // TODO start writing the initialisation pattern to the SD\r
  56         // card\r
  57         scsiDev.phase = STATUS;\r
  58 }\r
  59 \r
  60 static void doFormatUnitSkipData(int bytes)\r
  61 {\r
  62         // We may not have enough memory to store the initialisation pattern and\r
  63         // defect list data.  Since we're not making use of it yet anyway, just\r
  64         // discard the bytes.\r
  65         scsiEnterPhase(DATA_OUT);\r
  66         int i;\r
  67         for (i = 0; i < bytes; ++i)\r
  68         {\r
  69                 scsiReadByte();\r
  70         }\r
  71 }\r
  72 \r
  73 // Callback from the data out phase.\r
  74 static void doFormatUnitPatternHeader(void)\r
  75 {\r
  76         int defectLength =\r
  77                 ((((uint16_t)scsiDev.data[2])) << 8) +\r
  78                         scsiDev.data[3];\r
  79 \r
  80         int patternLength =\r
  81                 ((((uint16_t)scsiDev.data[4 + 2])) << 8) +\r
  82                 scsiDev.data[4 + 3];\r
  83 \r
  84                 doFormatUnitSkipData(defectLength + patternLength);\r
  85                 doFormatUnitComplete();\r
  86 }\r
  87 \r
  88 // Callback from the data out phase.\r
  89 static void doFormatUnitHeader(void)\r
  90 {\r
  91         int IP = (scsiDev.data[1] & 0x08) ? 1 : 0;\r
  92         int DSP = (scsiDev.data[1] & 0x04) ? 1 : 0;\r
  93 \r
  94         if (! DSP) // disable save parameters\r
  95         {\r
  96                 // Save the "MODE SELECT savable parameters"\r
  97                 configSave(\r
  98                         scsiDev.target->targetId,\r
  99                         scsiDev.target->liveCfg.bytesPerSector);\r
 100         }\r
 101 \r
 102         if (IP)\r
 103         {\r
 104                 // We need to read the initialisation pattern header first.\r
 105                 scsiDev.dataLen += 4;\r
 106                 scsiDev.phase = DATA_OUT;\r
 107                 scsiDev.postDataOutHook = doFormatUnitPatternHeader;\r
 108         }\r
 109         else\r
 110         {\r
 111                 // Read the defect list data\r
 112                 int defectLength =\r
 113                         ((((uint16_t)scsiDev.data[2])) << 8) +\r
 114                         scsiDev.data[3];\r
 115                 doFormatUnitSkipData(defectLength);\r
 116                 doFormatUnitComplete();\r
 117         }\r
 118 }\r
 119 \r
 120 static void doReadCapacity()\r
 121 {\r
 122         uint32_t lba = (((uint32) scsiDev.cdb[2]) << 24) +\r
 123                 (((uint32) scsiDev.cdb[3]) << 16) +\r
 124                 (((uint32) scsiDev.cdb[4]) << 8) +\r
 125                 scsiDev.cdb[5];\r
 126         int pmi = scsiDev.cdb[8] & 1;\r
 127 \r
 128         uint32_t capacity = getScsiCapacity(\r
 129                 scsiDev.target->cfg->sdSectorStart,\r
 130                 scsiDev.target->liveCfg.bytesPerSector,\r
 131                 scsiDev.target->cfg->scsiSectors);\r
 132 \r
 133         if (!pmi && lba)\r
 134         {\r
 135                 // error.\r
 136                 // We don't do anything with the "partial medium indicator", and\r
 137                 // assume that delays are constant across each block. But the spec\r
 138                 // says we must return this error if pmi is specified incorrectly.\r
 139                 scsiDev.status = CHECK_CONDITION;\r
 140                 scsiDev.target->sense.code = ILLEGAL_REQUEST;\r
 141                 scsiDev.target->sense.asc = INVALID_FIELD_IN_CDB;\r
 142                 scsiDev.phase = STATUS;\r
 143         }\r
 144         else if (capacity > 0)\r
 145         {\r
 146                 uint32_t highestBlock = capacity - 1;\r
 147 \r
 148                 scsiDev.data[0] = highestBlock >> 24;\r
 149                 scsiDev.data[1] = highestBlock >> 16;\r
 150                 scsiDev.data[2] = highestBlock >> 8;\r
 151                 scsiDev.data[3] = highestBlock;\r
 152 \r
 153                 uint32_t bytesPerSector = scsiDev.target->liveCfg.bytesPerSector;\r
 154                 scsiDev.data[4] = bytesPerSector >> 24;\r
 155                 scsiDev.data[5] = bytesPerSector >> 16;\r
 156                 scsiDev.data[6] = bytesPerSector >> 8;\r
 157                 scsiDev.data[7] = bytesPerSector;\r
 158                 scsiDev.dataLen = 8;\r
 159                 scsiDev.phase = DATA_IN;\r
 160         }\r
 161         else\r
 162         {\r
 163                 scsiDev.status = CHECK_CONDITION;\r
 164                 scsiDev.target->sense.code = NOT_READY;\r
 165                 scsiDev.target->sense.asc = MEDIUM_NOT_PRESENT;\r
 166                 scsiDev.phase = STATUS;\r
 167         }\r
 168 }\r
 169 \r
 170 static void doWrite(uint32 lba, uint32 blocks)\r
 171 {\r
 172         if (unlikely(blockDev.state & DISK_WP) ||\r
 173                 unlikely(scsiDev.target->cfg->deviceType == CONFIG_OPTICAL))\r
 174 \r
 175         {\r
 176                 scsiDev.status = CHECK_CONDITION;\r
 177                 scsiDev.target->sense.code = ILLEGAL_REQUEST;\r
 178                 scsiDev.target->sense.asc = WRITE_PROTECTED;\r
 179                 scsiDev.phase = STATUS;\r
 180         }\r
 181         else if (unlikely(((uint64) lba) + blocks >\r
 182                 getScsiCapacity(\r
 183                         scsiDev.target->cfg->sdSectorStart,\r
 184                         scsiDev.target->liveCfg.bytesPerSector,\r
 185                         scsiDev.target->cfg->scsiSectors\r
 186                         )\r
 187                 ))\r
 188         {\r
 189                 scsiDev.status = CHECK_CONDITION;\r
 190                 scsiDev.target->sense.code = ILLEGAL_REQUEST;\r
 191                 scsiDev.target->sense.asc = LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;\r
 192                 scsiDev.phase = STATUS;\r
 193         }\r
 194         else\r
 195         {\r
 196                 transfer.dir = TRANSFER_WRITE;\r
 197                 transfer.lba = lba;\r
 198                 transfer.blocks = blocks;\r
 199                 transfer.currentBlock = 0;\r
 200                 scsiDev.phase = DATA_OUT;\r
 201                 scsiDev.dataLen = scsiDev.target->liveCfg.bytesPerSector;\r
 202                 scsiDev.dataPtr = scsiDev.target->liveCfg.bytesPerSector;\r
 203 \r
 204                 // No need for single-block writes atm.  Overhead of the\r
 205                 // multi-block write is minimal.\r
 206                 transfer.multiBlock = 1;\r
 207 \r
 208                 sdWriteMultiSectorPrep();\r
 209         }\r
 210 }\r
 211 \r
 212 \r
 213 static void doRead(uint32 lba, uint32 blocks)\r
 214 {\r
 215         uint32_t capacity = getScsiCapacity(\r
 216                 scsiDev.target->cfg->sdSectorStart,\r
 217                 scsiDev.target->liveCfg.bytesPerSector,\r
 218                 scsiDev.target->cfg->scsiSectors);\r
 219         if (unlikely(((uint64) lba) + blocks > capacity))\r
 220         {\r
 221                 scsiDev.status = CHECK_CONDITION;\r
 222                 scsiDev.target->sense.code = ILLEGAL_REQUEST;\r
 223                 scsiDev.target->sense.asc = LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;\r
 224                 scsiDev.phase = STATUS;\r
 225         }\r
 226         else\r
 227         {\r
 228                 transfer.dir = TRANSFER_READ;\r
 229                 transfer.lba = lba;\r
 230                 transfer.blocks = blocks;\r
 231                 transfer.currentBlock = 0;\r
 232                 scsiDev.phase = DATA_IN;\r
 233                 scsiDev.dataLen = 0; // No data yet\r
 234 \r
 235                 if ((blocks == 1) ||\r
 236                         unlikely(((uint64) lba) + blocks == capacity)\r
 237                         )\r
 238                 {\r
 239                         // We get errors on reading the last sector using a multi-sector\r
 240                         // read :-(\r
 241                         transfer.multiBlock = 0;\r
 242                 }\r
 243                 else\r
 244                 {\r
 245                         transfer.multiBlock = 1;\r
 246                         sdReadMultiSectorPrep();\r
 247                 }\r
 248         }\r
 249 }\r
 250 \r
 251 static void doSeek(uint32 lba)\r
 252 {\r
 253         if (lba >=\r
 254                 getScsiCapacity(\r
 255                         scsiDev.target->cfg->sdSectorStart,\r
 256                         scsiDev.target->liveCfg.bytesPerSector,\r
 257                         scsiDev.target->cfg->scsiSectors)\r
 258                 )\r
 259         {\r
 260                 scsiDev.status = CHECK_CONDITION;\r
 261                 scsiDev.target->sense.code = ILLEGAL_REQUEST;\r
 262                 scsiDev.target->sense.asc = LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;\r
 263                 scsiDev.phase = STATUS;\r
 264         }\r
 265 }\r
 266 \r
 267 static int doTestUnitReady()\r
 268 {\r
 269         int ready = 1;\r
 270         if (likely(blockDev.state == (DISK_STARTED | DISK_PRESENT | DISK_INITIALISED)))\r
 271         {\r
 272                 // nothing to do.\r
 273         }\r
 274         else if (unlikely(!(blockDev.state & DISK_STARTED)))\r
 275         {\r
 276                 ready = 0;\r
 277                 scsiDev.status = CHECK_CONDITION;\r
 278                 scsiDev.target->sense.code = NOT_READY;\r
 279                 scsiDev.target->sense.asc = LOGICAL_UNIT_NOT_READY_INITIALIZING_COMMAND_REQUIRED;\r
 280                 scsiDev.phase = STATUS;\r
 281         }\r
 282         else if (unlikely(!(blockDev.state & DISK_PRESENT)))\r
 283         {\r
 284                 ready = 0;\r
 285                 scsiDev.status = CHECK_CONDITION;\r
 286                 scsiDev.target->sense.code = NOT_READY;\r
 287                 scsiDev.target->sense.asc = MEDIUM_NOT_PRESENT;\r
 288                 scsiDev.phase = STATUS;\r
 289         }\r
 290         else if (unlikely(!(blockDev.state & DISK_INITIALISED)))\r
 291         {\r
 292                 ready = 0;\r
 293                 scsiDev.status = CHECK_CONDITION;\r
 294                 scsiDev.target->sense.code = NOT_READY;\r
 295                 scsiDev.target->sense.asc = LOGICAL_UNIT_NOT_READY_CAUSE_NOT_REPORTABLE;\r
 296                 scsiDev.phase = STATUS;\r
 297         }\r
 298         return ready;\r
 299 }\r
 300 \r
 301 // Handle direct-access scsi device commands\r
 302 int scsiDiskCommand()\r
 303 {\r
 304         int commandHandled = 1;\r
 305 \r
 306         uint8 command = scsiDev.cdb[0];\r
 307         if (unlikely(command == 0x1B))\r
 308         {\r
 309                 // START STOP UNIT\r
 310                 // Enable or disable media access operations.\r
 311                 // Ignore load/eject requests. We can't do that.\r
 312                 //int immed = scsiDev.cdb[1] & 1;\r
 313                 int start = scsiDev.cdb[4] & 1;\r
 314 \r
 315                 if (start)\r
 316                 {\r
 317                         blockDev.state = blockDev.state | DISK_STARTED;\r
 318                         if (!(blockDev.state & DISK_INITIALISED))\r
 319                         {\r
 320                                 doSdInit();\r
 321                         }\r
 322                 }\r
 323                 else\r
 324                 {\r
 325                         blockDev.state &= ~DISK_STARTED;\r
 326                 }\r
 327         }\r
 328         else if (unlikely(command == 0x00))\r
 329         {\r
 330                 // TEST UNIT READY\r
 331                 doTestUnitReady();\r
 332         }\r
 333         else if (unlikely(!doTestUnitReady()))\r
 334         {\r
 335                 // Status and sense codes already set by doTestUnitReady\r
 336         }\r
 337         else if (likely(command == 0x08))\r
 338         {\r
 339                 // READ(6)\r
 340                 uint32 lba =\r
 341                         (((uint32) scsiDev.cdb[1] & 0x1F) << 16) +\r
 342                         (((uint32) scsiDev.cdb[2]) << 8) +\r
 343                         scsiDev.cdb[3];\r
 344                 uint32 blocks = scsiDev.cdb[4];\r
 345                 if (unlikely(blocks == 0)) blocks = 256;\r
 346                 doRead(lba, blocks);\r
 347         }\r
 348         else if (likely(command == 0x28))\r
 349         {\r
 350                 // READ(10)\r
 351                 // Ignore all cache control bits - we don't support a memory cache.\r
 352 \r
 353                 uint32 lba =\r
 354                         (((uint32) scsiDev.cdb[2]) << 24) +\r
 355                         (((uint32) scsiDev.cdb[3]) << 16) +\r
 356                         (((uint32) scsiDev.cdb[4]) << 8) +\r
 357                         scsiDev.cdb[5];\r
 358                 uint32 blocks =\r
 359                         (((uint32) scsiDev.cdb[7]) << 8) +\r
 360                         scsiDev.cdb[8];\r
 361 \r
 362                 doRead(lba, blocks);\r
 363         }\r
 364         else if (likely(command == 0x0A))\r
 365         {\r
 366                 // WRITE(6)\r
 367                 uint32 lba =\r
 368                         (((uint32) scsiDev.cdb[1] & 0x1F) << 16) +\r
 369                         (((uint32) scsiDev.cdb[2]) << 8) +\r
 370                         scsiDev.cdb[3];\r
 371                 uint32 blocks = scsiDev.cdb[4];\r
 372                 if (unlikely(blocks == 0)) blocks = 256;\r
 373                 doWrite(lba, blocks);\r
 374         }\r
 375         else if (likely(command == 0x2A) || // WRITE(10)\r
 376                 unlikely(command == 0x2E)) // WRITE AND VERIFY\r
 377         {\r
 378                 // Ignore all cache control bits - we don't support a memory cache.\r
 379                 // Don't bother verifying either. The SD card likely stores ECC\r
 380                 // along with each flash row.\r
 381 \r
 382                 uint32 lba =\r
 383                         (((uint32) scsiDev.cdb[2]) << 24) +\r
 384                         (((uint32) scsiDev.cdb[3]) << 16) +\r
 385                         (((uint32) scsiDev.cdb[4]) << 8) +\r
 386                         scsiDev.cdb[5];\r
 387                 uint32 blocks =\r
 388                         (((uint32) scsiDev.cdb[7]) << 8) +\r
 389                         scsiDev.cdb[8];\r
 390 \r
 391                 doWrite(lba, blocks);\r
 392         }\r
 393 \r
 394         else if (unlikely(command == 0x04))\r
 395         {\r
 396                 // FORMAT UNIT\r
 397                 // We don't really do any formatting, but we need to read the correct\r
 398                 // number of bytes in the DATA_OUT phase to make the SCSI host happy.\r
 399 \r
 400                 int fmtData = (scsiDev.cdb[1] & 0x10) ? 1 : 0;\r
 401                 if (fmtData)\r
 402                 {\r
 403                         // We need to read the parameter list, but we don't know how\r
 404                         // big it is yet. Start with the header.\r
 405                         scsiDev.dataLen = 4;\r
 406                         scsiDev.phase = DATA_OUT;\r
 407                         scsiDev.postDataOutHook = doFormatUnitHeader;\r
 408                 }\r
 409                 else\r
 410                 {\r
 411                         // No data to read, we're already finished!\r
 412                 }\r
 413         }\r
 414         else if (unlikely(command == 0x25))\r
 415         {\r
 416                 // READ CAPACITY\r
 417                 doReadCapacity();\r
 418         }\r
 419         else if (unlikely(command == 0x0B))\r
 420         {\r
 421                 // SEEK(6)\r
 422                 uint32 lba =\r
 423                         (((uint32) scsiDev.cdb[1] & 0x1F) << 16) +\r
 424                         (((uint32) scsiDev.cdb[2]) << 8) +\r
 425                         scsiDev.cdb[3];\r
 426 \r
 427                 doSeek(lba);\r
 428         }\r
 429 \r
 430         else if (unlikely(command == 0x2B))\r
 431         {\r
 432                 // SEEK(10)\r
 433                 uint32 lba =\r
 434                         (((uint32) scsiDev.cdb[2]) << 24) +\r
 435                         (((uint32) scsiDev.cdb[3]) << 16) +\r
 436                         (((uint32) scsiDev.cdb[4]) << 8) +\r
 437                         scsiDev.cdb[5];\r
 438 \r
 439                 doSeek(lba);\r
 440         }\r
 441         else if (unlikely(command == 0x36))\r
 442         {\r
 443                 // LOCK UNLOCK CACHE\r
 444                 // We don't have a cache to lock data into. do nothing.\r
 445         }\r
 446         else if (unlikely(command == 0x34))\r
 447         {\r
 448                 // PRE-FETCH.\r
 449                 // We don't have a cache to pre-fetch into. do nothing.\r
 450         }\r
 451         else if (unlikely(command == 0x1E))\r
 452         {\r
 453                 // PREVENT ALLOW MEDIUM REMOVAL\r
 454                 // Not much we can do to prevent the user removing the SD card.\r
 455                 // do nothing.\r
 456         }\r
 457         else if (unlikely(command == 0x01))\r
 458         {\r
 459                 // REZERO UNIT\r
 460                 // Set the lun to a vendor-specific state. Ignore.\r
 461         }\r
 462         else if (unlikely(command == 0x35))\r
 463         {\r
 464                 // SYNCHRONIZE CACHE\r
 465                 // We don't have a cache. do nothing.\r
 466         }\r
 467         else if (unlikely(command == 0x2F))\r
 468         {\r
 469                 // VERIFY\r
 470                 // TODO: When they supply data to verify, we should read the data and\r
 471                 // verify it. If they don't supply any data, just say success.\r
 472                 if ((scsiDev.cdb[1] & 0x02) == 0)\r
 473                 {\r
 474                         // They are asking us to do a medium verification with no data\r
 475                         // comparison. Assume success, do nothing.\r
 476                 }\r
 477                 else\r
 478                 {\r
 479                         // TODO. This means they are supplying data to verify against.\r
 480                         // Technically we should probably grab the data and compare it.\r
 481                         scsiDev.status = CHECK_CONDITION;\r
 482                         scsiDev.target->sense.code = ILLEGAL_REQUEST;\r
 483                         scsiDev.target->sense.asc = INVALID_FIELD_IN_CDB;\r
 484                         scsiDev.phase = STATUS;\r
 485                 }\r
 486         }\r
 487         else\r
 488         {\r
 489                 commandHandled = 0;\r
 490         }\r
 491 \r
 492         return commandHandled;\r
 493 }\r
 494 \r
 495 void scsiDiskPoll()\r
 496 {\r
 497         debugPause(); // TODO comment re. timeouts.\r
 498 \r
 499         if (scsiDev.phase == DATA_IN &&\r
 500                 transfer.currentBlock != transfer.blocks)\r
 501         {\r
 502                 scsiEnterPhase(DATA_IN);\r
 503 \r
 504                 int totalSDSectors =\r
 505                         transfer.blocks *\r
 506                                 SDSectorsPerSCSISector(scsiDev.target->liveCfg.bytesPerSector);\r
 507                 uint32_t sdLBA =\r
 508                         SCSISector2SD(\r
 509                                 scsiDev.target->cfg->sdSectorStart,\r
 510                                 scsiDev.target->liveCfg.bytesPerSector,\r
 511                                 transfer.lba);\r
 512 \r
 513                 const int sdPerScsi =\r
 514                         SDSectorsPerSCSISector(scsiDev.target->liveCfg.bytesPerSector);\r
 515                 int buffers = sizeof(scsiDev.data) / SD_SECTOR_SIZE;\r
 516                 int prep = 0;\r
 517                 int i = 0;\r
 518                 int scsiActive = 0;\r
 519                 int sdActive = 0;\r
 520                 while ((i < totalSDSectors) &&\r
 521                         likely(scsiDev.phase == DATA_IN) &&\r
 522                         likely(!scsiDev.resetFlag))\r
 523                 {\r
 524                         // Wait for the next DMA interrupt. It's beneficial to halt the\r
 525                         // processor to give the DMA controller more memory bandwidth to\r
 526                         // work with.\r
 527                         // We're optimistically assuming a race condition won't occur\r
 528                         // between these checks and the interrupt handers. The 1ms\r
 529                         // systick timer interrupt saves us on the event of a race.\r
 530                         int scsiBusy = scsiDMABusy();\r
 531                         int sdBusy = sdDMABusy();\r
 532                         if (scsiBusy && sdBusy) __WFI();\r
 533 \r
 534                         if (sdActive && !sdBusy && sdReadSectorDMAPoll())\r
 535                         {\r
 536                                 sdActive = 0;\r
 537                                 prep++;\r
 538                         }\r
 539                         else if (!sdActive &&\r
 540                                 (prep - i < buffers) &&\r
 541                                 (prep < totalSDSectors))\r
 542                         {\r
 543                                 // Start an SD transfer if we have space.\r
 544                                 if (transfer.multiBlock)\r
 545                                 {\r
 546                                         sdReadMultiSectorDMA(&scsiDev.data[SD_SECTOR_SIZE * (prep % buffers)]);\r
 547                                 }\r
 548                                 else\r
 549                                 {\r
 550                                         sdReadSingleSectorDMA(sdLBA + prep, &scsiDev.data[SD_SECTOR_SIZE * (prep % buffers)]);\r
 551                                 }\r
 552                                 sdActive = 1;\r
 553                         }\r
 554 \r
 555                         if (scsiActive && !scsiBusy && scsiWriteDMAPoll())\r
 556                         {\r
 557                                 scsiActive = 0;\r
 558                                 ++i;\r
 559                         }\r
 560                         else if (!scsiActive && ((prep - i) > 0))\r
 561                         {\r
 562                                 int dmaBytes = SD_SECTOR_SIZE;\r
 563                                 if ((i % sdPerScsi) == (sdPerScsi - 1))\r
 564                                 {\r
 565                                         dmaBytes = scsiDev.target->liveCfg.bytesPerSector % SD_SECTOR_SIZE;\r
 566                                         if (dmaBytes == 0) dmaBytes = SD_SECTOR_SIZE;\r
 567                                 }\r
 568                                 scsiWriteDMA(&scsiDev.data[SD_SECTOR_SIZE * (i % buffers)], dmaBytes);\r
 569                                 scsiActive = 1;\r
 570                         }\r
 571                 }\r
 572                 if (scsiDev.phase == DATA_IN)\r
 573                 {\r
 574                         scsiDev.phase = STATUS;\r
 575                 }\r
 576                 scsiDiskReset();\r
 577         }\r
 578         else if (scsiDev.phase == DATA_OUT &&\r
 579                 transfer.currentBlock != transfer.blocks)\r
 580         {\r
 581                 scsiEnterPhase(DATA_OUT);\r
 582 \r
 583                 const int sdPerScsi =\r
 584                         SDSectorsPerSCSISector(scsiDev.target->liveCfg.bytesPerSector);\r
 585                 int totalSDSectors = transfer.blocks * sdPerScsi;\r
 586                 int buffers = sizeof(scsiDev.data) / SD_SECTOR_SIZE;\r
 587                 int prep = 0;\r
 588                 int i = 0;\r
 589                 int scsiDisconnected = 0;\r
 590                 int scsiComplete = 0;\r
 591                 uint32_t lastActivityTime = getTime_ms();\r
 592                 int scsiActive = 0;\r
 593                 int sdActive = 0;\r
 594 \r
 595                 while ((i < totalSDSectors) &&\r
 596                         (likely(scsiDev.phase == DATA_OUT) || // scsiDisconnect keeps our phase.\r
 597                                 scsiComplete) &&\r
 598                         likely(!scsiDev.resetFlag))\r
 599                 {\r
 600                         // Wait for the next DMA interrupt. It's beneficial to halt the\r
 601                         // processor to give the DMA controller more memory bandwidth to\r
 602                         // work with.\r
 603                         // We're optimistically assuming a race condition won't occur\r
 604                         // between these checks and the interrupt handers. The 1ms\r
 605                         // systick timer interrupt saves us on the event of a race.\r
 606                         int scsiBusy = scsiDMABusy();\r
 607                         int sdBusy = sdDMABusy();\r
 608                         if (scsiBusy && sdBusy) __WFI();\r
 609 \r
 610                         if (sdActive && !sdBusy && sdWriteSectorDMAPoll(i == (totalSDSectors - 1)))\r
 611                         {\r
 612                                 sdActive = 0;\r
 613                                 i++;\r
 614                         }\r
 615                         else if (!sdActive && ((prep - i) > 0))\r
 616                         {\r
 617                                 // Start an SD transfer if we have space.\r
 618                                 sdWriteMultiSectorDMA(&scsiDev.data[SD_SECTOR_SIZE * (i % buffers)]);\r
 619                                 sdActive = 1;\r
 620                         }\r
 621 \r
 622                         uint32_t now = getTime_ms();\r
 623 \r
 624                         if (scsiActive && !scsiBusy && scsiReadDMAPoll())\r
 625                         {\r
 626                                 scsiActive = 0;\r
 627                                 ++prep;\r
 628                                 lastActivityTime = now;\r
 629                         }\r
 630                         else if (!scsiActive &&\r
 631                                 ((prep - i) < buffers) &&\r
 632                                 (prep < totalSDSectors) &&\r
 633                                 likely(!scsiDisconnected))\r
 634                         {\r
 635                                 int dmaBytes = SD_SECTOR_SIZE;\r
 636                                 if ((prep % sdPerScsi) == (sdPerScsi - 1))\r
 637                                 {\r
 638                                         dmaBytes = scsiDev.target->liveCfg.bytesPerSector % SD_SECTOR_SIZE;\r
 639                                         if (dmaBytes == 0) dmaBytes = SD_SECTOR_SIZE;\r
 640                                 }\r
 641                                 scsiReadDMA(&scsiDev.data[SD_SECTOR_SIZE * (prep % buffers)], dmaBytes);\r
 642                                 scsiActive = 1;\r
 643                         }\r
 644                         else if (\r
 645                                 (scsiActive == 0) &&\r
 646                                 likely(!scsiDisconnected) &&\r
 647                                 unlikely(scsiDev.discPriv) &&\r
 648                                 unlikely(diffTime_ms(lastActivityTime, now) >= 20) &&\r
 649                                 likely(scsiDev.phase == DATA_OUT))\r
 650                         {\r
 651                                 // We're transferring over the SCSI bus faster than the SD card\r
 652                                 // can write.  There is no more buffer space once we've finished\r
 653                                 // this SCSI transfer.\r
 654                                 // The NCR 53C700 interface chips have a 250ms "byte-to-byte"\r
 655                                 // timeout buffer. SD card writes are supposed to complete\r
 656                                 // within 200ms, but sometimes they don't.\r
 657                                 // The NCR 53C700 series is used on HP 9000 workstations.\r
 658                                 scsiDisconnect();\r
 659                                 scsiDisconnected = 1;\r
 660                                 lastActivityTime = getTime_ms();\r
 661                         }\r
 662                         else if (unlikely(scsiDisconnected) &&\r
 663                                 (\r
 664                                         (prep == i) || // Buffers empty.\r
 665                                         // Send some messages every 100ms so we don't timeout.\r
 666                                         // At a minimum, a reselection involves an IDENTIFY message.\r
 667                                         unlikely(diffTime_ms(lastActivityTime, now) >= 100)\r
 668                                 ))\r
 669                         {\r
 670                                 int reconnected = scsiReconnect();\r
 671                                 if (reconnected)\r
 672                                 {\r
 673                                         scsiDisconnected = 0;\r
 674                                         lastActivityTime = getTime_ms(); // Don't disconnect immediately.\r
 675                                 }\r
 676                                 else if (diffTime_ms(lastActivityTime, getTime_ms()) >= 10000)\r
 677                                 {\r
 678                                         // Give up after 10 seconds of trying to reconnect.\r
 679                                         scsiDev.resetFlag = 1;\r
 680                                 }\r
 681                         }\r
 682                         else if (\r
 683                                 likely(!scsiComplete) &&\r
 684                                 (sdActive == 1) &&\r
 685                                 (prep == totalSDSectors) && // All scsi data read and buffered\r
 686                                 likely(!scsiDev.discPriv) && // Prefer disconnect where possible.\r
 687                                 unlikely(diffTime_ms(lastActivityTime, now) >= 150) &&\r
 688 \r
 689                                 likely(scsiDev.phase == DATA_OUT) &&\r
 690                                 !(scsiDev.cdb[scsiDev.cdbLen - 1] & 0x01) // Not linked command\r
 691                                 )\r
 692                         {\r
 693                                 // We're transferring over the SCSI bus faster than the SD card\r
 694                                 // can write.  All data is buffered, and we're just waiting for\r
 695                                 // the SD card to complete. The host won't let us disconnect.\r
 696                                 // Some drivers set a 250ms timeout on transfers to complete.\r
 697                                 // SD card writes are supposed to complete\r
 698                                 // within 200ms, but sometimes they don'to.\r
 699                                 // Just pretend we're finished.\r
 700                                 scsiComplete = 1;\r
 701 \r
 702                                 process_Status();\r
 703                                 process_MessageIn(); // Will go to BUS_FREE state\r
 704 \r
 705                                 // Try and prevent anyone else using the SCSI bus while we're not ready.\r
 706                                 SCSI_SetPin(SCSI_Out_BSY); \r
 707                         }\r
 708                 }\r
 709 \r
 710                 if (scsiComplete)\r
 711                 {\r
 712                         SCSI_ClearPin(SCSI_Out_BSY);\r
 713                 }\r
 714                 while (\r
 715                         !scsiDev.resetFlag &&\r
 716                         unlikely(scsiDisconnected) &&\r
 717                         (elapsedTime_ms(lastActivityTime) <= 10000))\r
 718                 {\r
 719                         scsiDisconnected = !scsiReconnect();\r
 720                 }\r
 721                 if (scsiDisconnected)\r
 722                 {\r
 723                         // Failed to reconnect\r
 724                         scsiDev.resetFlag = 1;\r
 725                 }\r
 726 \r
 727                 if (scsiDev.phase == DATA_OUT)\r
 728                 {\r
 729                         if (scsiDev.parityError &&\r
 730                                 (scsiDev.target->cfg->flags & CONFIG_ENABLE_PARITY) &&\r
 731                                 !scsiDev.compatMode)\r
 732                         {\r
 733                                 scsiDev.target->sense.code = ABORTED_COMMAND;\r
 734                                 scsiDev.target->sense.asc = SCSI_PARITY_ERROR;\r
 735                                 scsiDev.status = CHECK_CONDITION;;\r
 736                         }\r
 737                         scsiDev.phase = STATUS;\r
 738                 }\r
 739                 scsiDiskReset();\r
 740         }\r
 741         debugResume(); // TODO comment re. timeouts.\r
 742 }\r
 743 \r
 744 void scsiDiskReset()\r
 745 {\r
 746         scsiDev.dataPtr = 0;\r
 747         scsiDev.savedDataPtr = 0;\r
 748         scsiDev.dataLen = 0;\r
 749         // transfer.lba = 0; // Needed in Request Sense to determine failure\r
 750         transfer.blocks = 0;\r
 751         transfer.currentBlock = 0;\r
 752 \r
 753         // Cancel long running commands!\r
 754         if (unlikely(transfer.inProgress == 1))\r
 755         {\r
 756                 if (transfer.dir == TRANSFER_WRITE)\r
 757                 {\r
 758                         sdCompleteWrite();\r
 759                 }\r
 760                 else\r
 761                 {\r
 762                         sdCompleteRead();\r
 763                 }\r
 764         }\r
 765         transfer.inProgress = 0;\r
 766         transfer.multiBlock = 0;\r
 767 }\r
 768 \r
 769 void scsiDiskInit()\r
 770 {\r
 771         transfer.inProgress = 0;\r
 772         scsiDiskReset();\r
 773 \r
 774         // Don't require the host to send us a START STOP UNIT command\r
 775         blockDev.state = DISK_STARTED;\r
 776         // WP pin not available for micro-sd\r
 777         // TODO read card WP register\r
 778         #if 0\r
 779         if (SD_WP_Read())\r
 780         {\r
 781                 blockDev.state = blockDev.state | DISK_WP;\r
 782         }\r
 783         #endif\r
 784 }\r
 785 \r
 786 #pragma GCC pop_options\r