drivers/scsi/NCR5380.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * NCR 5380 generic driver routines.  These should make it *trivial*
   4  * to implement 5380 SCSI drivers under Linux with a non-trantor
   5  * architecture.
   6  *
   7  * Note that these routines also work with NR53c400 family chips.
   8  *
   9  * Copyright 1993, Drew Eckhardt
  10  * Visionary Computing
  11  * (Unix and Linux consulting and custom programming)
  12  * drew@colorado.edu
  13  * +1 (303) 666-5836
  14  *
  15  * For more information, please consult
  16  *
  17  * NCR 5380 Family
  18  * SCSI Protocol Controller
  19  * Databook
  20  *
  21  * NCR Microelectronics
  22  * 1635 Aeroplaza Drive
  23  * Colorado Springs, CO 80916
  24  * 1+ (719) 578-3400
  25  * 1+ (800) 334-5454
  26  */
  27
  28 /*
  29  * With contributions from Ray Van Tassle, Ingmar Baumgart,
  30  * Ronald van Cuijlenborg, Alan Cox and others.
  31  */
  32
  33 /* Ported to Atari by Roman Hodek and others. */
  34
  35 /* Adapted for the Sun 3 by Sam Creasey. */
  36
  37 /*
  38  * Design
  39  *
  40  * This is a generic 5380 driver.  To use it on a different platform,
  41  * one simply writes appropriate system specific macros (ie, data
  42  * transfer - some PC's will use the I/O bus, 68K's must use
  43  * memory mapped) and drops this file in their 'C' wrapper.
  44  *
  45  * As far as command queueing, two queues are maintained for
  46  * each 5380 in the system - commands that haven't been issued yet,
  47  * and commands that are currently executing.  This means that an
  48  * unlimited number of commands may be queued, letting
  49  * more commands propagate from the higher driver levels giving higher
  50  * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported,
  51  * allowing multiple commands to propagate all the way to a SCSI-II device
  52  * while a command is already executing.
  53  *
  54  *
  55  * Issues specific to the NCR5380 :
  56  *
  57  * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
  58  * piece of hardware that requires you to sit in a loop polling for
  59  * the REQ signal as long as you are connected.  Some devices are
  60  * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
  61  * while doing long seek operations. [...] These
  62  * broken devices are the exception rather than the rule and I'd rather
  63  * spend my time optimizing for the normal case.
  64  *
  65  * Architecture :
  66  *
  67  * At the heart of the design is a coroutine, NCR5380_main,
  68  * which is started from a workqueue for each NCR5380 host in the
  69  * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
  70  * removing the commands from the issue queue and calling
  71  * NCR5380_select() if a nexus is not established.
  72  *
  73  * Once a nexus is established, the NCR5380_information_transfer()
  74  * phase goes through the various phases as instructed by the target.
  75  * if the target goes into MSG IN and sends a DISCONNECT message,
  76  * the command structure is placed into the per instance disconnected
  77  * queue, and NCR5380_main tries to find more work.  If the target is
  78  * idle for too long, the system will try to sleep.
  79  *
  80  * If a command has disconnected, eventually an interrupt will trigger,
  81  * calling NCR5380_intr()  which will in turn call NCR5380_reselect
  82  * to reestablish a nexus.  This will run main if necessary.
  83  *
  84  * On command termination, the done function will be called as
  85  * appropriate.
  86  *
  87  * SCSI pointers are maintained in the SCp field of SCSI command
  88  * structures, being initialized after the command is connected
  89  * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
  90  * Note that in violation of the standard, an implicit SAVE POINTERS operation
  91  * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
  92  */
  93
  94 /*
  95  * Using this file :
  96  * This file a skeleton Linux SCSI driver for the NCR 5380 series
  97  * of chips.  To use it, you write an architecture specific functions
  98  * and macros and include this file in your driver.
  99  *
 100  * These macros MUST be defined :
 101  *
 102  * NCR5380_read(register)  - read from the specified register
 103  *
 104  * NCR5380_write(register, value) - write to the specific register
 105  *
 106  * NCR5380_implementation_fields  - additional fields needed for this
 107  * specific implementation of the NCR5380
 108  *
 109  * Either real DMA *or* pseudo DMA may be implemented
 110  *
 111  * NCR5380_dma_xfer_len   - determine size of DMA/PDMA transfer
 112  * NCR5380_dma_send_setup - execute DMA/PDMA from memory to 5380
 113  * NCR5380_dma_recv_setup - execute DMA/PDMA from 5380 to memory
 114  * NCR5380_dma_residual   - residual byte count
 115  *
 116  * The generic driver is initialized by calling NCR5380_init(instance),
 117  * after setting the appropriate host specific fields and ID.
 118  */
 119
 120 #ifndef NCR5380_io_delay
 121 #define NCR5380_io_delay(x)
 122 #endif
 123
 124 #ifndef NCR5380_acquire_dma_irq
 125 #define NCR5380_acquire_dma_irq(x)      (1)
 126 #endif
 127
 128 #ifndef NCR5380_release_dma_irq
 129 #define NCR5380_release_dma_irq(x)
 130 #endif
 131
 132 static int do_abort(struct Scsi_Host *);
 133 static void do_reset(struct Scsi_Host *);
 134 static void bus_reset_cleanup(struct Scsi_Host *);
 135
 136 /**
 137  * initialize_SCp - init the scsi pointer field
 138  * @cmd: command block to set up
 139  *
 140  * Set up the internal fields in the SCSI command.
 141  */
 142
 143 static inline void initialize_SCp(struct scsi_cmnd *cmd)
 144 {
 145         /*
 146          * Initialize the Scsi Pointer field so that all of the commands in the
 147          * various queues are valid.
 148          */
 149
 150         if (scsi_bufflen(cmd)) {
 151                 cmd->SCp.buffer = scsi_sglist(cmd);
 152                 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
 153                 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
 154                 cmd->SCp.this_residual = cmd->SCp.buffer->length;
 155         } else {
 156                 cmd->SCp.buffer = NULL;
 157                 cmd->SCp.buffers_residual = 0;
 158                 cmd->SCp.ptr = NULL;
 159                 cmd->SCp.this_residual = 0;
 160         }
 161
 162         cmd->SCp.Status = 0;
 163         cmd->SCp.Message = 0;
 164 }
 165
 166 /**
 167  * NCR5380_poll_politely2 - wait for two chip register values
 168  * @hostdata: host private data
 169  * @reg1: 5380 register to poll
 170  * @bit1: Bitmask to check
 171  * @val1: Expected value
 172  * @reg2: Second 5380 register to poll
 173  * @bit2: Second bitmask to check
 174  * @val2: Second expected value
 175  * @wait: Time-out in jiffies
 176  *
 177  * Polls the chip in a reasonably efficient manner waiting for an
 178  * event to occur. After a short quick poll we begin to yield the CPU
 179  * (if possible). In irq contexts the time-out is arbitrarily limited.
 180  * Callers may hold locks as long as they are held in irq mode.
 181  *
 182  * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.
 183  */
 184
 185 static int NCR5380_poll_politely2(struct NCR5380_hostdata *hostdata,
 186                                   unsigned int reg1, u8 bit1, u8 val1,
 187                                   unsigned int reg2, u8 bit2, u8 val2,
 188                                   unsigned long wait)
 189 {
 190         unsigned long n = hostdata->poll_loops;
 191         unsigned long deadline = jiffies + wait;
 192
 193         do {
 194                 if ((NCR5380_read(reg1) & bit1) == val1)
 195                         return 0;
 196                 if ((NCR5380_read(reg2) & bit2) == val2)
 197                         return 0;
 198                 cpu_relax();
 199         } while (n--);
 200
 201         if (irqs_disabled() || in_interrupt())
 202                 return -ETIMEDOUT;
 203
 204         /* Repeatedly sleep for 1 ms until deadline */
 205         while (time_is_after_jiffies(deadline)) {
 206                 schedule_timeout_uninterruptible(1);
 207                 if ((NCR5380_read(reg1) & bit1) == val1)
 208                         return 0;
 209                 if ((NCR5380_read(reg2) & bit2) == val2)
 210                         return 0;
 211         }
 212
 213         return -ETIMEDOUT;
 214 }
 215
 216 #if NDEBUG
 217 static struct {
 218         unsigned char mask;
 219         const char *name;
 220 } signals[] = {
 221         {SR_DBP, "PARITY"},
 222         {SR_RST, "RST"},
 223         {SR_BSY, "BSY"},
 224         {SR_REQ, "REQ"},
 225         {SR_MSG, "MSG"},
 226         {SR_CD, "CD"},
 227         {SR_IO, "IO"},
 228         {SR_SEL, "SEL"},
 229         {0, NULL}
 230 },
 231 basrs[] = {
 232         {BASR_END_DMA_TRANSFER, "END OF DMA"},
 233         {BASR_DRQ, "DRQ"},
 234         {BASR_PARITY_ERROR, "PARITY ERROR"},
 235         {BASR_IRQ, "IRQ"},
 236         {BASR_PHASE_MATCH, "PHASE MATCH"},
 237         {BASR_BUSY_ERROR, "BUSY ERROR"},
 238         {BASR_ATN, "ATN"},
 239         {BASR_ACK, "ACK"},
 240         {0, NULL}
 241 },
 242 icrs[] = {
 243         {ICR_ASSERT_RST, "ASSERT RST"},
 244         {ICR_ARBITRATION_PROGRESS, "ARB. IN PROGRESS"},
 245         {ICR_ARBITRATION_LOST, "LOST ARB."},
 246         {ICR_ASSERT_ACK, "ASSERT ACK"},
 247         {ICR_ASSERT_BSY, "ASSERT BSY"},
 248         {ICR_ASSERT_SEL, "ASSERT SEL"},
 249         {ICR_ASSERT_ATN, "ASSERT ATN"},
 250         {ICR_ASSERT_DATA, "ASSERT DATA"},
 251         {0, NULL}
 252 },
 253 mrs[] = {
 254         {MR_BLOCK_DMA_MODE, "BLOCK DMA MODE"},
 255         {MR_TARGET, "TARGET"},
 256         {MR_ENABLE_PAR_CHECK, "PARITY CHECK"},
 257         {MR_ENABLE_PAR_INTR, "PARITY INTR"},
 258         {MR_ENABLE_EOP_INTR, "EOP INTR"},
 259         {MR_MONITOR_BSY, "MONITOR BSY"},
 260         {MR_DMA_MODE, "DMA MODE"},
 261         {MR_ARBITRATE, "ARBITRATE"},
 262         {0, NULL}
 263 };
 264
 265 /**
 266  * NCR5380_print - print scsi bus signals
 267  * @instance: adapter state to dump
 268  *
 269  * Print the SCSI bus signals for debugging purposes
 270  */
 271
 272 static void NCR5380_print(struct Scsi_Host *instance)
 273 {
 274         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 275         unsigned char status, data, basr, mr, icr, i;
 276
 277         data = NCR5380_read(CURRENT_SCSI_DATA_REG);
 278         status = NCR5380_read(STATUS_REG);
 279         mr = NCR5380_read(MODE_REG);
 280         icr = NCR5380_read(INITIATOR_COMMAND_REG);
 281         basr = NCR5380_read(BUS_AND_STATUS_REG);
 282
 283         printk(KERN_DEBUG "SR =   0x%02x : ", status);
 284         for (i = 0; signals[i].mask; ++i)
 285                 if (status & signals[i].mask)
 286                         printk(KERN_CONT "%s, ", signals[i].name);
 287         printk(KERN_CONT "\nBASR = 0x%02x : ", basr);
 288         for (i = 0; basrs[i].mask; ++i)
 289                 if (basr & basrs[i].mask)
 290                         printk(KERN_CONT "%s, ", basrs[i].name);
 291         printk(KERN_CONT "\nICR =  0x%02x : ", icr);
 292         for (i = 0; icrs[i].mask; ++i)
 293                 if (icr & icrs[i].mask)
 294                         printk(KERN_CONT "%s, ", icrs[i].name);
 295         printk(KERN_CONT "\nMR =   0x%02x : ", mr);
 296         for (i = 0; mrs[i].mask; ++i)
 297                 if (mr & mrs[i].mask)
 298                         printk(KERN_CONT "%s, ", mrs[i].name);
 299         printk(KERN_CONT "\n");
 300 }
 301
 302 static struct {
 303         unsigned char value;
 304         const char *name;
 305 } phases[] = {
 306         {PHASE_DATAOUT, "DATAOUT"},
 307         {PHASE_DATAIN, "DATAIN"},
 308         {PHASE_CMDOUT, "CMDOUT"},
 309         {PHASE_STATIN, "STATIN"},
 310         {PHASE_MSGOUT, "MSGOUT"},
 311         {PHASE_MSGIN, "MSGIN"},
 312         {PHASE_UNKNOWN, "UNKNOWN"}
 313 };
 314
 315 /**
 316  * NCR5380_print_phase - show SCSI phase
 317  * @instance: adapter to dump
 318  *
 319  * Print the current SCSI phase for debugging purposes
 320  */
 321
 322 static void NCR5380_print_phase(struct Scsi_Host *instance)
 323 {
 324         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 325         unsigned char status;
 326         int i;
 327
 328         status = NCR5380_read(STATUS_REG);
 329         if (!(status & SR_REQ))
 330                 shost_printk(KERN_DEBUG, instance, "REQ not asserted, phase unknown.\n");
 331         else {
 332                 for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
 333                      (phases[i].value != (status & PHASE_MASK)); ++i)
 334                         ;
 335                 shost_printk(KERN_DEBUG, instance, "phase %s\n", phases[i].name);
 336         }
 337 }
 338 #endif
 339
 340 /**
 341  * NCR5380_info - report driver and host information
 342  * @instance: relevant scsi host instance
 343  *
 344  * For use as the host template info() handler.
 345  */
 346
 347 static const char *NCR5380_info(struct Scsi_Host *instance)
 348 {
 349         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 350
 351         return hostdata->info;
 352 }
 353
 354 /**
 355  * NCR5380_init - initialise an NCR5380
 356  * @instance: adapter to configure
 357  * @flags: control flags
 358  *
 359  * Initializes *instance and corresponding 5380 chip,
 360  * with flags OR'd into the initial flags value.
 361  *
 362  * Notes : I assume that the host, hostno, and id bits have been
 363  * set correctly. I don't care about the irq and other fields.
 364  *
 365  * Returns 0 for success
 366  */
 367
 368 static int NCR5380_init(struct Scsi_Host *instance, int flags)
 369 {
 370         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 371         int i;
 372         unsigned long deadline;
 373         unsigned long accesses_per_ms;
 374
 375         instance->max_lun = 7;
 376
 377         hostdata->host = instance;
 378         hostdata->id_mask = 1 << instance->this_id;
 379         hostdata->id_higher_mask = 0;
 380         for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
 381                 if (i > hostdata->id_mask)
 382                         hostdata->id_higher_mask |= i;
 383         for (i = 0; i < 8; ++i)
 384                 hostdata->busy[i] = 0;
 385         hostdata->dma_len = 0;
 386
 387         spin_lock_init(&hostdata->lock);
 388         hostdata->connected = NULL;
 389         hostdata->sensing = NULL;
 390         INIT_LIST_HEAD(&hostdata->autosense);
 391         INIT_LIST_HEAD(&hostdata->unissued);
 392         INIT_LIST_HEAD(&hostdata->disconnected);
 393
 394         hostdata->flags = flags;
 395
 396         INIT_WORK(&hostdata->main_task, NCR5380_main);
 397         hostdata->work_q = alloc_workqueue("ncr5380_%d",
 398                                 WQ_UNBOUND | WQ_MEM_RECLAIM,
 399                                 1, instance->host_no);
 400         if (!hostdata->work_q)
 401                 return -ENOMEM;
 402
 403         snprintf(hostdata->info, sizeof(hostdata->info),
 404                 "%s, irq %d, io_port 0x%lx, base 0x%lx, can_queue %d, cmd_per_lun %d, sg_tablesize %d, this_id %d, flags { %s%s%s}",
 405                 instance->hostt->name, instance->irq, hostdata->io_port,
 406                 hostdata->base, instance->can_queue, instance->cmd_per_lun,
 407                 instance->sg_tablesize, instance->this_id,
 408                 hostdata->flags & FLAG_DMA_FIXUP     ? "DMA_FIXUP "     : "",
 409                 hostdata->flags & FLAG_NO_PSEUDO_DMA ? "NO_PSEUDO_DMA " : "",
 410                 hostdata->flags & FLAG_TOSHIBA_DELAY ? "TOSHIBA_DELAY " : "");
 411
 412         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
 413         NCR5380_write(MODE_REG, MR_BASE);
 414         NCR5380_write(TARGET_COMMAND_REG, 0);
 415         NCR5380_write(SELECT_ENABLE_REG, 0);
 416
 417         /* Calibrate register polling loop */
 418         i = 0;
 419         deadline = jiffies + 1;
 420         do {
 421                 cpu_relax();
 422         } while (time_is_after_jiffies(deadline));
 423         deadline += msecs_to_jiffies(256);
 424         do {
 425                 NCR5380_read(STATUS_REG);
 426                 ++i;
 427                 cpu_relax();
 428         } while (time_is_after_jiffies(deadline));
 429         accesses_per_ms = i / 256;
 430         hostdata->poll_loops = NCR5380_REG_POLL_TIME * accesses_per_ms / 2;
 431
 432         return 0;
 433 }
 434
 435 /**
 436  * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems.
 437  * @instance: adapter to check
 438  *
 439  * If the system crashed, it may have crashed with a connected target and
 440  * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the
 441  * currently established nexus, which we know nothing about. Failing that
 442  * do a bus reset.
 443  *
 444  * Note that a bus reset will cause the chip to assert IRQ.
 445  *
 446  * Returns 0 if successful, otherwise -ENXIO.
 447  */
 448
 449 static int NCR5380_maybe_reset_bus(struct Scsi_Host *instance)
 450 {
 451         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 452         int pass;
 453
 454         for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
 455                 switch (pass) {
 456                 case 1:
 457                 case 3:
 458                 case 5:
 459                         shost_printk(KERN_ERR, instance, "SCSI bus busy, waiting up to five seconds\n");
 460                         NCR5380_poll_politely(hostdata,
 461                                               STATUS_REG, SR_BSY, 0, 5 * HZ);
 462                         break;
 463                 case 2:
 464                         shost_printk(KERN_ERR, instance, "bus busy, attempting abort\n");
 465                         do_abort(instance);
 466                         break;
 467                 case 4:
 468                         shost_printk(KERN_ERR, instance, "bus busy, attempting reset\n");
 469                         do_reset(instance);
 470                         /* Wait after a reset; the SCSI standard calls for
 471                          * 250ms, we wait 500ms to be on the safe side.
 472                          * But some Toshiba CD-ROMs need ten times that.
 473                          */
 474                         if (hostdata->flags & FLAG_TOSHIBA_DELAY)
 475                                 msleep(2500);
 476                         else
 477                                 msleep(500);
 478                         break;
 479                 case 6:
 480                         shost_printk(KERN_ERR, instance, "bus locked solid\n");
 481                         return -ENXIO;
 482                 }
 483         }
 484         return 0;
 485 }
 486
 487 /**
 488  * NCR5380_exit - remove an NCR5380
 489  * @instance: adapter to remove
 490  *
 491  * Assumes that no more work can be queued (e.g. by NCR5380_intr).
 492  */
 493
 494 static void NCR5380_exit(struct Scsi_Host *instance)
 495 {
 496         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 497
 498         cancel_work_sync(&hostdata->main_task);
 499         destroy_workqueue(hostdata->work_q);
 500 }
 501
 502 /**
 503  * complete_cmd - finish processing a command and return it to the SCSI ML
 504  * @instance: the host instance
 505  * @cmd: command to complete
 506  */
 507
 508 static void complete_cmd(struct Scsi_Host *instance,
 509                          struct scsi_cmnd *cmd)
 510 {
 511         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 512
 513         dsprintk(NDEBUG_QUEUES, instance, "complete_cmd: cmd %p\n", cmd);
 514
 515         if (hostdata->sensing == cmd) {
 516                 /* Autosense processing ends here */
 517                 if (status_byte(cmd->result) != GOOD) {
 518                         scsi_eh_restore_cmnd(cmd, &hostdata->ses);
 519                 } else {
 520                         scsi_eh_restore_cmnd(cmd, &hostdata->ses);
 521                         set_driver_byte(cmd, DRIVER_SENSE);
 522                 }
 523                 hostdata->sensing = NULL;
 524         }
 525
 526         cmd->scsi_done(cmd);
 527 }
 528
 529 /**
 530  * NCR5380_queue_command - queue a command
 531  * @instance: the relevant SCSI adapter
 532  * @cmd: SCSI command
 533  *
 534  * cmd is added to the per-instance issue queue, with minor
 535  * twiddling done to the host specific fields of cmd.  If the
 536  * main coroutine is not running, it is restarted.
 537  */
 538
 539 static int NCR5380_queue_command(struct Scsi_Host *instance,
 540                                  struct scsi_cmnd *cmd)
 541 {
 542         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 543         struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);
 544         unsigned long flags;
 545
 546 #if (NDEBUG & NDEBUG_NO_WRITE)
 547         switch (cmd->cmnd[0]) {
 548         case WRITE_6:
 549         case WRITE_10:
 550                 shost_printk(KERN_DEBUG, instance, "WRITE attempted with NDEBUG_NO_WRITE set\n");
 551                 cmd->result = (DID_ERROR << 16);
 552                 cmd->scsi_done(cmd);
 553                 return 0;
 554         }
 555 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
 556
 557         cmd->result = 0;
 558
 559         if (!NCR5380_acquire_dma_irq(instance))
 560                 return SCSI_MLQUEUE_HOST_BUSY;
 561
 562         spin_lock_irqsave(&hostdata->lock, flags);
 563
 564         /*
 565          * Insert the cmd into the issue queue. Note that REQUEST SENSE
 566          * commands are added to the head of the queue since any command will
 567          * clear the contingent allegiance condition that exists and the
 568          * sense data is only guaranteed to be valid while the condition exists.
 569          */
 570
 571         if (cmd->cmnd[0] == REQUEST_SENSE)
 572                 list_add(&ncmd->list, &hostdata->unissued);
 573         else
 574                 list_add_tail(&ncmd->list, &hostdata->unissued);
 575
 576         spin_unlock_irqrestore(&hostdata->lock, flags);
 577
 578         dsprintk(NDEBUG_QUEUES, instance, "command %p added to %s of queue\n",
 579                  cmd, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
 580
 581         /* Kick off command processing */
 582         queue_work(hostdata->work_q, &hostdata->main_task);
 583         return 0;
 584 }
 585
 586 static inline void maybe_release_dma_irq(struct Scsi_Host *instance)
 587 {
 588         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 589
 590         /* Caller does the locking needed to set & test these data atomically */
 591         if (list_empty(&hostdata->disconnected) &&
 592             list_empty(&hostdata->unissued) &&
 593             list_empty(&hostdata->autosense) &&
 594             !hostdata->connected &&
 595             !hostdata->selecting) {
 596                 NCR5380_release_dma_irq(instance);
 597         }
 598 }
 599
 600 /**
 601  * dequeue_next_cmd - dequeue a command for processing
 602  * @instance: the scsi host instance
 603  *
 604  * Priority is given to commands on the autosense queue. These commands
 605  * need autosense because of a CHECK CONDITION result.
 606  *
 607  * Returns a command pointer if a command is found for a target that is
 608  * not already busy. Otherwise returns NULL.
 609  */
 610
 611 static struct scsi_cmnd *dequeue_next_cmd(struct Scsi_Host *instance)
 612 {
 613         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 614         struct NCR5380_cmd *ncmd;
 615         struct scsi_cmnd *cmd;
 616
 617         if (hostdata->sensing || list_empty(&hostdata->autosense)) {
 618                 list_for_each_entry(ncmd, &hostdata->unissued, list) {
 619                         cmd = NCR5380_to_scmd(ncmd);
 620                         dsprintk(NDEBUG_QUEUES, instance, "dequeue: cmd=%p target=%d busy=0x%02x lun=%llu\n",
 621                                  cmd, scmd_id(cmd), hostdata->busy[scmd_id(cmd)], cmd->device->lun);
 622
 623                         if (!(hostdata->busy[scmd_id(cmd)] & (1 << cmd->device->lun))) {
 624                                 list_del(&ncmd->list);
 625                                 dsprintk(NDEBUG_QUEUES, instance,
 626                                          "dequeue: removed %p from issue queue\n", cmd);
 627                                 return cmd;
 628                         }
 629                 }
 630         } else {
 631                 /* Autosense processing begins here */
 632                 ncmd = list_first_entry(&hostdata->autosense,
 633                                         struct NCR5380_cmd, list);
 634                 list_del(&ncmd->list);
 635                 cmd = NCR5380_to_scmd(ncmd);
 636                 dsprintk(NDEBUG_QUEUES, instance,
 637                          "dequeue: removed %p from autosense queue\n", cmd);
 638                 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
 639                 hostdata->sensing = cmd;
 640                 return cmd;
 641         }
 642         return NULL;
 643 }
 644
 645 static void requeue_cmd(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
 646 {
 647         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 648         struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);
 649
 650         if (hostdata->sensing == cmd) {
 651                 scsi_eh_restore_cmnd(cmd, &hostdata->ses);
 652                 list_add(&ncmd->list, &hostdata->autosense);
 653                 hostdata->sensing = NULL;
 654         } else
 655                 list_add(&ncmd->list, &hostdata->unissued);
 656 }
 657
 658 /**
 659  * NCR5380_main - NCR state machines
 660  *
 661  * NCR5380_main is a coroutine that runs as long as more work can
 662  * be done on the NCR5380 host adapters in a system.  Both
 663  * NCR5380_queue_command() and NCR5380_intr() will try to start it
 664  * in case it is not running.
 665  */
 666
 667 static void NCR5380_main(struct work_struct *work)
 668 {
 669         struct NCR5380_hostdata *hostdata =
 670                 container_of(work, struct NCR5380_hostdata, main_task);
 671         struct Scsi_Host *instance = hostdata->host;
 672         int done;
 673
 674         do {
 675                 done = 1;
 676
 677                 spin_lock_irq(&hostdata->lock);
 678                 while (!hostdata->connected && !hostdata->selecting) {
 679                         struct scsi_cmnd *cmd = dequeue_next_cmd(instance);
 680
 681                         if (!cmd)
 682                                 break;
 683
 684                         dsprintk(NDEBUG_MAIN, instance, "main: dequeued %p\n", cmd);
 685
 686                         /*
 687                          * Attempt to establish an I_T_L nexus here.
 688                          * On success, instance->hostdata->connected is set.
 689                          * On failure, we must add the command back to the
 690                          * issue queue so we can keep trying.
 691                          */
 692                         /*
 693                          * REQUEST SENSE commands are issued without tagged
 694                          * queueing, even on SCSI-II devices because the
 695                          * contingent allegiance condition exists for the
 696                          * entire unit.
 697                          */
 698
 699                         if (!NCR5380_select(instance, cmd)) {
 700                                 dsprintk(NDEBUG_MAIN, instance, "main: select complete\n");
 701                                 maybe_release_dma_irq(instance);
 702                         } else {
 703                                 dsprintk(NDEBUG_MAIN | NDEBUG_QUEUES, instance,
 704                                          "main: select failed, returning %p to queue\n", cmd);
 705                                 requeue_cmd(instance, cmd);
 706                         }
 707                 }
 708                 if (hostdata->connected && !hostdata->dma_len) {
 709                         dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n");
 710                         NCR5380_information_transfer(instance);
 711                         done = 0;
 712                 }
 713                 spin_unlock_irq(&hostdata->lock);
 714                 if (!done)
 715                         cond_resched();
 716         } while (!done);
 717 }
 718
 719 /*
 720  * NCR5380_dma_complete - finish DMA transfer
 721  * @instance: the scsi host instance
 722  *
 723  * Called by the interrupt handler when DMA finishes or a phase
 724  * mismatch occurs (which would end the DMA transfer).
 725  */
 726
 727 static void NCR5380_dma_complete(struct Scsi_Host *instance)
 728 {
 729         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 730         int transferred;
 731         unsigned char **data;
 732         int *count;
 733         int saved_data = 0, overrun = 0;
 734         unsigned char p;
 735
 736         if (hostdata->read_overruns) {
 737                 p = hostdata->connected->SCp.phase;
 738                 if (p & SR_IO) {
 739                         udelay(10);
 740                         if ((NCR5380_read(BUS_AND_STATUS_REG) &
 741                              (BASR_PHASE_MATCH | BASR_ACK)) ==
 742                             (BASR_PHASE_MATCH | BASR_ACK)) {
 743                                 saved_data = NCR5380_read(INPUT_DATA_REG);
 744                                 overrun = 1;
 745                                 dsprintk(NDEBUG_DMA, instance, "read overrun handled\n");
 746                         }
 747                 }
 748         }
 749
 750 #ifdef CONFIG_SUN3
 751         if ((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) {
 752                 pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n",
 753                        instance->host_no);
 754                 BUG();
 755         }
 756
 757         if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) ==
 758             (BASR_PHASE_MATCH | BASR_ACK)) {
 759                 pr_err("scsi%d: BASR %02x\n", instance->host_no,
 760                        NCR5380_read(BUS_AND_STATUS_REG));
 761                 pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n",
 762                        instance->host_no);
 763                 BUG();
 764         }
 765 #endif
 766
 767         NCR5380_write(MODE_REG, MR_BASE);
 768         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
 769         NCR5380_read(RESET_PARITY_INTERRUPT_REG);
 770
 771         transferred = hostdata->dma_len - NCR5380_dma_residual(hostdata);
 772         hostdata->dma_len = 0;
 773
 774         data = (unsigned char **)&hostdata->connected->SCp.ptr;
 775         count = &hostdata->connected->SCp.this_residual;
 776         *data += transferred;
 777         *count -= transferred;
 778
 779         if (hostdata->read_overruns) {
 780                 int cnt, toPIO;
 781
 782                 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
 783                         cnt = toPIO = hostdata->read_overruns;
 784                         if (overrun) {
 785                                 dsprintk(NDEBUG_DMA, instance,
 786                                          "Got an input overrun, using saved byte\n");
 787                                 *(*data)++ = saved_data;
 788                                 (*count)--;
 789                                 cnt--;
 790                                 toPIO--;
 791                         }
 792                         if (toPIO > 0) {
 793                                 dsprintk(NDEBUG_DMA, instance,
 794                                          "Doing %d byte PIO to 0x%p\n", cnt, *data);
 795                                 NCR5380_transfer_pio(instance, &p, &cnt, data);
 796                                 *count -= toPIO - cnt;
 797                         }
 798                 }
 799         }
 800 }
 801
 802 /**
 803  * NCR5380_intr - generic NCR5380 irq handler
 804  * @irq: interrupt number
 805  * @dev_id: device info
 806  *
 807  * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
 808  * from the disconnected queue, and restarting NCR5380_main()
 809  * as required.
 810  *
 811  * The chip can assert IRQ in any of six different conditions. The IRQ flag
 812  * is then cleared by reading the Reset Parity/Interrupt Register (RPIR).
 813  * Three of these six conditions are latched in the Bus and Status Register:
 814  * - End of DMA (cleared by ending DMA Mode)
 815  * - Parity error (cleared by reading RPIR)
 816  * - Loss of BSY (cleared by reading RPIR)
 817  * Two conditions have flag bits that are not latched:
 818  * - Bus phase mismatch (non-maskable in DMA Mode, cleared by ending DMA Mode)
 819  * - Bus reset (non-maskable)
 820  * The remaining condition has no flag bit at all:
 821  * - Selection/reselection
 822  *
 823  * Hence, establishing the cause(s) of any interrupt is partly guesswork.
 824  * In "The DP8490 and DP5380 Comparison Guide", National Semiconductor
 825  * claimed that "the design of the [DP8490] interrupt logic ensures
 826  * interrupts will not be lost (they can be on the DP5380)."
 827  * The L5380/53C80 datasheet from LOGIC Devices has more details.
 828  *
 829  * Checking for bus reset by reading RST is futile because of interrupt
 830  * latency, but a bus reset will reset chip logic. Checking for parity error
 831  * is unnecessary because that interrupt is never enabled. A Loss of BSY
 832  * condition will clear DMA Mode. We can tell when this occurs because the
 833  * the Busy Monitor interrupt is enabled together with DMA Mode.
 834  */
 835
 836 static irqreturn_t __maybe_unused NCR5380_intr(int irq, void *dev_id)
 837 {
 838         struct Scsi_Host *instance = dev_id;
 839         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 840         int handled = 0;
 841         unsigned char basr;
 842         unsigned long flags;
 843
 844         spin_lock_irqsave(&hostdata->lock, flags);
 845
 846         basr = NCR5380_read(BUS_AND_STATUS_REG);
 847         if (basr & BASR_IRQ) {
 848                 unsigned char mr = NCR5380_read(MODE_REG);
 849                 unsigned char sr = NCR5380_read(STATUS_REG);
 850
 851                 dsprintk(NDEBUG_INTR, instance, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
 852                          irq, basr, sr, mr);
 853
 854                 if ((mr & MR_DMA_MODE) || (mr & MR_MONITOR_BSY)) {
 855                         /* Probably End of DMA, Phase Mismatch or Loss of BSY.
 856                          * We ack IRQ after clearing Mode Register. Workarounds
 857                          * for End of DMA errata need to happen in DMA Mode.
 858                          */
 859
 860                         dsprintk(NDEBUG_INTR, instance, "interrupt in DMA mode\n");
 861
 862                         if (hostdata->connected) {
 863                                 NCR5380_dma_complete(instance);
 864                                 queue_work(hostdata->work_q, &hostdata->main_task);
 865                         } else {
 866                                 NCR5380_write(MODE_REG, MR_BASE);
 867                                 NCR5380_read(RESET_PARITY_INTERRUPT_REG);
 868                         }
 869                 } else if ((NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_mask) &&
 870                     (sr & (SR_SEL | SR_IO | SR_BSY | SR_RST)) == (SR_SEL | SR_IO)) {
 871                         /* Probably reselected */
 872                         NCR5380_write(SELECT_ENABLE_REG, 0);
 873                         NCR5380_read(RESET_PARITY_INTERRUPT_REG);
 874
 875                         dsprintk(NDEBUG_INTR, instance, "interrupt with SEL and IO\n");
 876
 877                         if (!hostdata->connected) {
 878                                 NCR5380_reselect(instance);
 879                                 queue_work(hostdata->work_q, &hostdata->main_task);
 880                         }
 881                         if (!hostdata->connected)
 882                                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
 883                 } else {
 884                         /* Probably Bus Reset */
 885                         NCR5380_read(RESET_PARITY_INTERRUPT_REG);
 886
 887                         if (sr & SR_RST) {
 888                                 /* Certainly Bus Reset */
 889                                 shost_printk(KERN_WARNING, instance,
 890                                              "bus reset interrupt\n");
 891                                 bus_reset_cleanup(instance);
 892                         } else {
 893                                 dsprintk(NDEBUG_INTR, instance, "unknown interrupt\n");
 894                         }
 895 #ifdef SUN3_SCSI_VME
 896                         dregs->csr |= CSR_DMA_ENABLE;
 897 #endif
 898                 }
 899                 handled = 1;
 900         } else {
 901                 dsprintk(NDEBUG_INTR, instance, "interrupt without IRQ bit\n");
 902 #ifdef SUN3_SCSI_VME
 903                 dregs->csr |= CSR_DMA_ENABLE;
 904 #endif
 905         }
 906
 907         spin_unlock_irqrestore(&hostdata->lock, flags);
 908
 909         return IRQ_RETVAL(handled);
 910 }
 911
 912 /**
 913  * NCR5380_select - attempt arbitration and selection for a given command
 914  * @instance: the Scsi_Host instance
 915  * @cmd: the scsi_cmnd to execute
 916  *
 917  * This routine establishes an I_T_L nexus for a SCSI command. This involves
 918  * ARBITRATION, SELECTION and MESSAGE OUT phases and an IDENTIFY message.
 919  *
 920  * Returns true if the operation should be retried.
 921  * Returns false if it should not be retried.
 922  *
 923  * Side effects :
 924  * If bus busy, arbitration failed, etc, NCR5380_select() will exit
 925  * with registers as they should have been on entry - ie
 926  * SELECT_ENABLE will be set appropriately, the NCR5380
 927  * will cease to drive any SCSI bus signals.
 928  *
 929  * If successful : the I_T_L nexus will be established, and
 930  * hostdata->connected will be set to cmd.
 931  * SELECT interrupt will be disabled.
 932  *
 933  * If failed (no target) : cmd->scsi_done() will be called, and the
 934  * cmd->result host byte set to DID_BAD_TARGET.
 935  */
 936
 937 static bool NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
 938         __releases(&hostdata->lock) __acquires(&hostdata->lock)
 939 {
 940         struct NCR5380_hostdata *hostdata = shost_priv(instance);
 941         unsigned char tmp[3], phase;
 942         unsigned char *data;
 943         int len;
 944         int err;
 945         bool ret = true;
 946         bool can_disconnect = instance->irq != NO_IRQ &&
 947                               cmd->cmnd[0] != REQUEST_SENSE;
 948
 949         NCR5380_dprint(NDEBUG_ARBITRATION, instance);
 950         dsprintk(NDEBUG_ARBITRATION, instance, "starting arbitration, id = %d\n",
 951                  instance->this_id);
 952
 953         /*
 954          * Arbitration and selection phases are slow and involve dropping the
 955          * lock, so we have to watch out for EH. An exception handler may
 956          * change 'selecting' to NULL. This function will then return false
 957          * so that the caller will forget about 'cmd'. (During information
 958          * transfer phases, EH may change 'connected' to NULL.)
 959          */
 960         hostdata->selecting = cmd;
 961
 962         /*
 963          * Set the phase bits to 0, otherwise the NCR5380 won't drive the
 964          * data bus during SELECTION.
 965          */
 966
 967         NCR5380_write(TARGET_COMMAND_REG, 0);
 968
 969         /*
 970          * Start arbitration.
 971          */
 972
 973         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
 974         NCR5380_write(MODE_REG, MR_ARBITRATE);
 975
 976         /* The chip now waits for BUS FREE phase. Then after the 800 ns
 977          * Bus Free Delay, arbitration will begin.
 978          */
 979
 980         spin_unlock_irq(&hostdata->lock);
 981         err = NCR5380_poll_politely2(hostdata, MODE_REG, MR_ARBITRATE, 0,
 982                         INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,
 983                                                ICR_ARBITRATION_PROGRESS, HZ);
 984         spin_lock_irq(&hostdata->lock);
 985         if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
 986                 /* Reselection interrupt */
 987                 goto out;
 988         }
 989         if (!hostdata->selecting) {
 990                 /* Command was aborted */
 991                 NCR5380_write(MODE_REG, MR_BASE);
 992                 return false;
 993         }
 994         if (err < 0) {
 995                 NCR5380_write(MODE_REG, MR_BASE);
 996                 shost_printk(KERN_ERR, instance,
 997                              "select: arbitration timeout\n");
 998                 goto out;
 999         }
1000         spin_unlock_irq(&hostdata->lock);
1001
1002         /* The SCSI-2 arbitration delay is 2.4 us */
1003         udelay(3);
1004
1005         /* Check for lost arbitration */
1006         if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1007             (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1008             (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1009                 NCR5380_write(MODE_REG, MR_BASE);
1010                 dsprintk(NDEBUG_ARBITRATION, instance, "lost arbitration, deasserting MR_ARBITRATE\n");
1011                 spin_lock_irq(&hostdata->lock);
1012                 goto out;
1013         }
1014
1015         /* After/during arbitration, BSY should be asserted.
1016          * IBM DPES-31080 Version S31Q works now
1017          * Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman)
1018          */
1019         NCR5380_write(INITIATOR_COMMAND_REG,
1020                       ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY);
1021
1022         /*
1023          * Again, bus clear + bus settle time is 1.2us, however, this is
1024          * a minimum so we'll udelay ceil(1.2)
1025          */
1026
1027         if (hostdata->flags & FLAG_TOSHIBA_DELAY)
1028                 udelay(15);
1029         else
1030                 udelay(2);
1031
1032         spin_lock_irq(&hostdata->lock);
1033
1034         /* NCR5380_reselect() clears MODE_REG after a reselection interrupt */
1035         if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE))
1036                 goto out;
1037
1038         if (!hostdata->selecting) {
1039                 NCR5380_write(MODE_REG, MR_BASE);
1040                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1041                 return false;
1042         }
1043
1044         dsprintk(NDEBUG_ARBITRATION, instance, "won arbitration\n");
1045
1046         /*
1047          * Now that we have won arbitration, start Selection process, asserting
1048          * the host and target ID's on the SCSI bus.
1049          */
1050
1051         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask | (1 << scmd_id(cmd)));
1052
1053         /*
1054          * Raise ATN while SEL is true before BSY goes false from arbitration,
1055          * since this is the only way to guarantee that we'll get a MESSAGE OUT
1056          * phase immediately after selection.
1057          */
1058
1059         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY |
1060                       ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL);
1061         NCR5380_write(MODE_REG, MR_BASE);
1062
1063         /*
1064          * Reselect interrupts must be turned off prior to the dropping of BSY,
1065          * otherwise we will trigger an interrupt.
1066          */
1067         NCR5380_write(SELECT_ENABLE_REG, 0);
1068
1069         spin_unlock_irq(&hostdata->lock);
1070
1071         /*
1072          * The initiator shall then wait at least two deskew delays and release
1073          * the BSY signal.
1074          */
1075         udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
1076
1077         /* Reset BSY */
1078         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA |
1079                       ICR_ASSERT_ATN | ICR_ASSERT_SEL);
1080
1081         /*
1082          * Something weird happens when we cease to drive BSY - looks
1083          * like the board/chip is letting us do another read before the
1084          * appropriate propagation delay has expired, and we're confusing
1085          * a BSY signal from ourselves as the target's response to SELECTION.
1086          *
1087          * A small delay (the 'C++' frontend breaks the pipeline with an
1088          * unnecessary jump, making it work on my 386-33/Trantor T128, the
1089          * tighter 'C' code breaks and requires this) solves the problem -
1090          * the 1 us delay is arbitrary, and only used because this delay will
1091          * be the same on other platforms and since it works here, it should
1092          * work there.
1093          *
1094          * wingel suggests that this could be due to failing to wait
1095          * one deskew delay.
1096          */
1097
1098         udelay(1);
1099
1100         dsprintk(NDEBUG_SELECTION, instance, "selecting target %d\n", scmd_id(cmd));
1101
1102         /*
1103          * The SCSI specification calls for a 250 ms timeout for the actual
1104          * selection.
1105          */
1106
1107         err = NCR5380_poll_politely(hostdata, STATUS_REG, SR_BSY, SR_BSY,
1108                                     msecs_to_jiffies(250));
1109
1110         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1111                 spin_lock_irq(&hostdata->lock);
1112                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1113                 NCR5380_reselect(instance);
1114                 if (!hostdata->connected)
1115                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1116                 shost_printk(KERN_ERR, instance, "reselection after won arbitration?\n");
1117                 goto out;
1118         }
1119
1120         if (err < 0) {
1121                 spin_lock_irq(&hostdata->lock);
1122                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1123                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1124
1125                 /* Can't touch cmd if it has been reclaimed by the scsi ML */
1126                 if (!hostdata->selecting)
1127                         return false;
1128
1129                 cmd->result = DID_BAD_TARGET << 16;
1130                 complete_cmd(instance, cmd);
1131                 dsprintk(NDEBUG_SELECTION, instance,
1132                         "target did not respond within 250ms\n");
1133                 ret = false;
1134                 goto out;
1135         }
1136
1137         /*
1138          * No less than two deskew delays after the initiator detects the
1139          * BSY signal is true, it shall release the SEL signal and may
1140          * change the DATA BUS.                                     -wingel
1141          */
1142
1143         udelay(1);
1144
1145         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1146
1147         /*
1148          * Since we followed the SCSI spec, and raised ATN while SEL
1149          * was true but before BSY was false during selection, the information
1150          * transfer phase should be a MESSAGE OUT phase so that we can send the
1151          * IDENTIFY message.
1152          */
1153
1154         /* Wait for start of REQ/ACK handshake */
1155
1156         err = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ);
1157         spin_lock_irq(&hostdata->lock);
1158         if (err < 0) {
1159                 shost_printk(KERN_ERR, instance, "select: REQ timeout\n");
1160                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1161                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1162                 goto out;
1163         }
1164         if (!hostdata->selecting) {
1165                 do_abort(instance);
1166                 return false;
1167         }
1168
1169         dsprintk(NDEBUG_SELECTION, instance, "target %d selected, going into MESSAGE OUT phase.\n",
1170                  scmd_id(cmd));
1171         tmp[0] = IDENTIFY(can_disconnect, cmd->device->lun);
1172
1173         len = 1;
1174         data = tmp;
1175         phase = PHASE_MSGOUT;
1176         NCR5380_transfer_pio(instance, &phase, &len, &data);
1177         if (len) {
1178                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1179                 cmd->result = DID_ERROR << 16;
1180                 complete_cmd(instance, cmd);
1181                 dsprintk(NDEBUG_SELECTION, instance, "IDENTIFY message transfer failed\n");
1182                 ret = false;
1183                 goto out;
1184         }
1185
1186         dsprintk(NDEBUG_SELECTION, instance, "nexus established.\n");
1187
1188         hostdata->connected = cmd;
1189         hostdata->busy[cmd->device->id] |= 1 << cmd->device->lun;
1190
1191 #ifdef SUN3_SCSI_VME
1192         dregs->csr |= CSR_INTR;
1193 #endif
1194
1195         initialize_SCp(cmd);
1196
1197         ret = false;
1198
1199 out:
1200         if (!hostdata->selecting)
1201                 return NULL;
1202         hostdata->selecting = NULL;
1203         return ret;
1204 }
1205
1206 /*
1207  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1208  * unsigned char *phase, int *count, unsigned char **data)
1209  *
1210  * Purpose : transfers data in given phase using polled I/O
1211  *
1212  * Inputs : instance - instance of driver, *phase - pointer to
1213  * what phase is expected, *count - pointer to number of
1214  * bytes to transfer, **data - pointer to data pointer.
1215  *
1216  * Returns : -1 when different phase is entered without transferring
1217  * maximum number of bytes, 0 if all bytes are transferred or exit
1218  * is in same phase.
1219  *
1220  * Also, *phase, *count, *data are modified in place.
1221  *
1222  * XXX Note : handling for bus free may be useful.
1223  */
1224
1225 /*
1226  * Note : this code is not as quick as it could be, however it
1227  * IS 100% reliable, and for the actual data transfer where speed
1228  * counts, we will always do a pseudo DMA or DMA transfer.
1229  */
1230
1231 static int NCR5380_transfer_pio(struct Scsi_Host *instance,
1232                                 unsigned char *phase, int *count,
1233                                 unsigned char **data)
1234 {
1235         struct NCR5380_hostdata *hostdata = shost_priv(instance);
1236         unsigned char p = *phase, tmp;
1237         int c = *count;
1238         unsigned char *d = *data;
1239
1240         /*
1241          * The NCR5380 chip will only drive the SCSI bus when the
1242          * phase specified in the appropriate bits of the TARGET COMMAND
1243          * REGISTER match the STATUS REGISTER
1244          */
1245
1246         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1247
1248         do {
1249                 /*
1250                  * Wait for assertion of REQ, after which the phase bits will be
1251                  * valid
1252                  */
1253
1254                 if (NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ) < 0)
1255                         break;
1256
1257                 dsprintk(NDEBUG_HANDSHAKE, instance, "REQ asserted\n");
1258
1259                 /* Check for phase mismatch */
1260                 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) != p) {
1261                         dsprintk(NDEBUG_PIO, instance, "phase mismatch\n");
1262                         NCR5380_dprint_phase(NDEBUG_PIO, instance);
1263                         break;
1264                 }
1265
1266                 /* Do actual transfer from SCSI bus to / from memory */
1267                 if (!(p & SR_IO))
1268                         NCR5380_write(OUTPUT_DATA_REG, *d);
1269                 else
1270                         *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1271
1272                 ++d;
1273
1274                 /*
1275                  * The SCSI standard suggests that in MSGOUT phase, the initiator
1276                  * should drop ATN on the last byte of the message phase
1277                  * after REQ has been asserted for the handshake but before
1278                  * the initiator raises ACK.
1279                  */
1280
1281                 if (!(p & SR_IO)) {
1282                         if (!((p & SR_MSG) && c > 1)) {
1283                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1284                                 NCR5380_dprint(NDEBUG_PIO, instance);
1285                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1286                                               ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1287                         } else {
1288                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1289                                               ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1290                                 NCR5380_dprint(NDEBUG_PIO, instance);
1291                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1292                                               ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1293                         }
1294                 } else {
1295                         NCR5380_dprint(NDEBUG_PIO, instance);
1296                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1297                 }
1298
1299                 if (NCR5380_poll_politely(hostdata,
1300                                           STATUS_REG, SR_REQ, 0, 5 * HZ) < 0)
1301                         break;
1302
1303                 dsprintk(NDEBUG_HANDSHAKE, instance, "REQ negated, handshake complete\n");
1304
1305 /*
1306  * We have several special cases to consider during REQ/ACK handshaking :
1307  * 1.  We were in MSGOUT phase, and we are on the last byte of the
1308  * message.  ATN must be dropped as ACK is dropped.
1309  *
1310  * 2.  We are in a MSGIN phase, and we are on the last byte of the
1311  * message.  We must exit with ACK asserted, so that the calling
1312  * code may raise ATN before dropping ACK to reject the message.
1313  *
1314  * 3.  ACK and ATN are clear and the target may proceed as normal.
1315  */
1316                 if (!(p == PHASE_MSGIN && c == 1)) {
1317                         if (p == PHASE_MSGOUT && c > 1)
1318                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1319                         else
1320                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1321                 }
1322         } while (--c);
1323
1324         dsprintk(NDEBUG_PIO, instance, "residual %d\n", c);
1325
1326         *count = c;
1327         *data = d;
1328         tmp = NCR5380_read(STATUS_REG);
1329         /* The phase read from the bus is valid if either REQ is (already)
1330          * asserted or if ACK hasn't been released yet. The latter applies if
1331          * we're in MSG IN, DATA IN or STATUS and all bytes have been received.
1332          */
1333         if ((tmp & SR_REQ) || ((tmp & SR_IO) && c == 0))
1334                 *phase = tmp & PHASE_MASK;
1335         else
1336                 *phase = PHASE_UNKNOWN;
1337
1338         if (!c || (*phase == p))
1339                 return 0;
1340         else
1341                 return -1;
1342 }
1343
1344 /**
1345  * do_reset - issue a reset command
1346  * @instance: adapter to reset
1347  *
1348  * Issue a reset sequence to the NCR5380 and try and get the bus
1349  * back into sane shape.
1350  *
1351  * This clears the reset interrupt flag because there may be no handler for
1352  * it. When the driver is initialized, the NCR5380_intr() handler has not yet
1353  * been installed. And when in EH we may have released the ST DMA interrupt.
1354  */
1355
1356 static void do_reset(struct Scsi_Host *instance)
1357 {
1358         struct NCR5380_hostdata __maybe_unused *hostdata = shost_priv(instance);
1359         unsigned long flags;
1360
1361         local_irq_save(flags);
1362         NCR5380_write(TARGET_COMMAND_REG,
1363                       PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
1364         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1365         udelay(50);
1366         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1367         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1368         local_irq_restore(flags);
1369 }
1370
1371 /**
1372  * do_abort - abort the currently established nexus by going to
1373  * MESSAGE OUT phase and sending an ABORT message.
1374  * @instance: relevant scsi host instance
1375  *
1376  * Returns 0 on success, -1 on failure.
1377  */
1378
1379 static int do_abort(struct Scsi_Host *instance)
1380 {
1381         struct NCR5380_hostdata *hostdata = shost_priv(instance);
1382         unsigned char *msgptr, phase, tmp;
1383         int len;
1384         int rc;
1385
1386         /* Request message out phase */
1387         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1388
1389         /*
1390          * Wait for the target to indicate a valid phase by asserting
1391          * REQ.  Once this happens, we'll have either a MSGOUT phase
1392          * and can immediately send the ABORT message, or we'll have some
1393          * other phase and will have to source/sink data.
1394          *
1395          * We really don't care what value was on the bus or what value
1396          * the target sees, so we just handshake.
1397          */
1398
1399         rc = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, 10 * HZ);
1400         if (rc < 0)
1401                 goto timeout;
1402
1403         tmp = NCR5380_read(STATUS_REG) & PHASE_MASK;
1404
1405         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1406
1407         if (tmp != PHASE_MSGOUT) {
1408                 NCR5380_write(INITIATOR_COMMAND_REG,
1409                               ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1410                 rc = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, 0, 3 * HZ);
1411                 if (rc < 0)
1412                         goto timeout;
1413                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1414         }
1415
1416         tmp = ABORT;
1417         msgptr = &tmp;
1418         len = 1;
1419         phase = PHASE_MSGOUT;
1420         NCR5380_transfer_pio(instance, &phase, &len, &msgptr);
1421
1422         /*
1423          * If we got here, and the command completed successfully,
1424          * we're about to go into bus free state.
1425          */
1426
1427         return len ? -1 : 0;
1428
1429 timeout:
1430         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1431         return -1;
1432 }
1433
1434 /*
1435  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1436  * unsigned char *phase, int *count, unsigned char **data)
1437  *
1438  * Purpose : transfers data in given phase using either real
1439  * or pseudo DMA.
1440  *
1441  * Inputs : instance - instance of driver, *phase - pointer to
1442  * what phase is expected, *count - pointer to number of
1443  * bytes to transfer, **data - pointer to data pointer.
1444  *
1445  * Returns : -1 when different phase is entered without transferring
1446  * maximum number of bytes, 0 if all bytes or transferred or exit
1447  * is in same phase.
1448  *
1449  * Also, *phase, *count, *data are modified in place.
1450  */
1451
1452
1453 static int NCR5380_transfer_dma(struct Scsi_Host *instance,
1454                                 unsigned char *phase, int *count,
1455                                 unsigned char **data)
1456 {
1457         struct NCR5380_hostdata *hostdata = shost_priv(instance);
1458         int c = *count;
1459         unsigned char p = *phase;
1460         unsigned char *d = *data;
1461         unsigned char tmp;
1462         int result = 0;
1463
1464         if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1465                 *phase = tmp;
1466                 return -1;
1467         }
1468
1469         hostdata->connected->SCp.phase = p;
1470
1471         if (p & SR_IO) {
1472                 if (hostdata->read_overruns)
1473                         c -= hostdata->read_overruns;
1474                 else if (hostdata->flags & FLAG_DMA_FIXUP)
1475                         --c;
1476         }
1477
1478         dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n",
1479                  (p & SR_IO) ? "receive" : "send", c, d);
1480
1481 #ifdef CONFIG_SUN3
1482         /* send start chain */
1483         sun3scsi_dma_start(c, *data);
1484 #endif
1485
1486         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1487         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY |
1488                                 MR_ENABLE_EOP_INTR);
1489
1490         if (!(hostdata->flags & FLAG_LATE_DMA_SETUP)) {
1491                 /* On the Medusa, it is a must to initialize the DMA before
1492                  * starting the NCR. This is also the cleaner way for the TT.
1493                  */
1494                 if (p & SR_IO)
1495                         result = NCR5380_dma_recv_setup(hostdata, d, c);
1496                 else
1497                         result = NCR5380_dma_send_setup(hostdata, d, c);
1498         }
1499
1500         /*
1501          * On the PAS16 at least I/O recovery delays are not needed here.
1502          * Everyone else seems to want them.
1503          */
1504
1505         if (p & SR_IO) {
1506                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1507                 NCR5380_io_delay(1);
1508                 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1509         } else {
1510                 NCR5380_io_delay(1);
1511                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1512                 NCR5380_io_delay(1);
1513                 NCR5380_write(START_DMA_SEND_REG, 0);
1514                 NCR5380_io_delay(1);
1515         }
1516
1517 #ifdef CONFIG_SUN3
1518 #ifdef SUN3_SCSI_VME
1519         dregs->csr |= CSR_DMA_ENABLE;
1520 #endif
1521         sun3_dma_active = 1;
1522 #endif
1523
1524         if (hostdata->flags & FLAG_LATE_DMA_SETUP) {
1525                 /* On the Falcon, the DMA setup must be done after the last
1526                  * NCR access, else the DMA setup gets trashed!
1527                  */
1528                 if (p & SR_IO)
1529                         result = NCR5380_dma_recv_setup(hostdata, d, c);
1530                 else
1531                         result = NCR5380_dma_send_setup(hostdata, d, c);
1532         }
1533
1534         /* On failure, NCR5380_dma_xxxx_setup() returns a negative int. */
1535         if (result < 0)
1536                 return result;
1537
1538         /* For real DMA, result is the byte count. DMA interrupt is expected. */
1539         if (result > 0) {
1540                 hostdata->dma_len = result;
1541                 return 0;
1542         }
1543
1544         /* The result is zero iff pseudo DMA send/receive was completed. */
1545         hostdata->dma_len = c;
1546
1547 /*
1548  * A note regarding the DMA errata workarounds for early NMOS silicon.
1549  *
1550  * For DMA sends, we want to wait until the last byte has been
1551  * transferred out over the bus before we turn off DMA mode.  Alas, there
1552  * seems to be no terribly good way of doing this on a 5380 under all
1553  * conditions.  For non-scatter-gather operations, we can wait until REQ
1554  * and ACK both go false, or until a phase mismatch occurs.  Gather-sends
1555  * are nastier, since the device will be expecting more data than we
1556  * are prepared to send it, and REQ will remain asserted.  On a 53C8[01] we
1557  * could test Last Byte Sent to assure transfer (I imagine this is precisely
1558  * why this signal was added to the newer chips) but on the older 538[01]
1559  * this signal does not exist.  The workaround for this lack is a watchdog;
1560  * we bail out of the wait-loop after a modest amount of wait-time if
1561  * the usual exit conditions are not met.  Not a terribly clean or
1562  * correct solution :-%
1563  *
1564  * DMA receive is equally tricky due to a nasty characteristic of the NCR5380.
1565  * If the chip is in DMA receive mode, it will respond to a target's
1566  * REQ by latching the SCSI data into the INPUT DATA register and asserting
1567  * ACK, even if it has _already_ been notified by the DMA controller that
1568  * the current DMA transfer has completed!  If the NCR5380 is then taken
1569  * out of DMA mode, this already-acknowledged byte is lost. This is
1570  * not a problem for "one DMA transfer per READ command", because
1571  * the situation will never arise... either all of the data is DMA'ed
1572  * properly, or the target switches to MESSAGE IN phase to signal a
1573  * disconnection (either operation bringing the DMA to a clean halt).
1574  * However, in order to handle scatter-receive, we must work around the
1575  * problem.  The chosen fix is to DMA fewer bytes, then check for the
1576  * condition before taking the NCR5380 out of DMA mode.  One or two extra
1577  * bytes are transferred via PIO as necessary to fill out the original
1578  * request.
1579  */
1580
1581         if (hostdata->flags & FLAG_DMA_FIXUP) {
1582                 if (p & SR_IO) {
1583                         /*
1584                          * The workaround was to transfer fewer bytes than we
1585                          * intended to with the pseudo-DMA read function, wait for
1586                          * the chip to latch the last byte, read it, and then disable
1587                          * pseudo-DMA mode.
1588                          *
1589                          * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
1590                          * REQ is deasserted when ACK is asserted, and not reasserted
1591                          * until ACK goes false.  Since the NCR5380 won't lower ACK
1592                          * until DACK is asserted, which won't happen unless we twiddle
1593                          * the DMA port or we take the NCR5380 out of DMA mode, we
1594                          * can guarantee that we won't handshake another extra
1595                          * byte.
1596                          */
1597
1598                         if (NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
1599                                                   BASR_DRQ, BASR_DRQ, HZ) < 0) {
1600                                 result = -1;
1601                                 shost_printk(KERN_ERR, instance, "PDMA read: DRQ timeout\n");
1602                         }
1603                         if (NCR5380_poll_politely(hostdata, STATUS_REG,
1604                                                   SR_REQ, 0, HZ) < 0) {
1605                                 result = -1;
1606                                 shost_printk(KERN_ERR, instance, "PDMA read: !REQ timeout\n");
1607                         }
1608                         d[*count - 1] = NCR5380_read(INPUT_DATA_REG);
1609                 } else {
1610                         /*
1611                          * Wait for the last byte to be sent.  If REQ is being asserted for
1612                          * the byte we're interested, we'll ACK it and it will go false.
1613                          */
1614                         if (NCR5380_poll_politely2(hostdata,
1615                              BUS_AND_STATUS_REG, BASR_DRQ, BASR_DRQ,
1616                              BUS_AND_STATUS_REG, BASR_PHASE_MATCH, 0, HZ) < 0) {
1617                                 result = -1;
1618                                 shost_printk(KERN_ERR, instance, "PDMA write: DRQ and phase timeout\n");
1619                         }
1620                 }
1621         }
1622
1623         NCR5380_dma_complete(instance);
1624         return result;
1625 }
1626
1627 /*
1628  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1629  *
1630  * Purpose : run through the various SCSI phases and do as the target
1631  * directs us to.  Operates on the currently connected command,
1632  * instance->connected.
1633  *
1634  * Inputs : instance, instance for which we are doing commands
1635  *
1636  * Side effects : SCSI things happen, the disconnected queue will be
1637  * modified if a command disconnects, *instance->connected will
1638  * change.
1639  *
1640  * XXX Note : we need to watch for bus free or a reset condition here
1641  * to recover from an unexpected bus free condition.
1642  */
1643
1644 static void NCR5380_information_transfer(struct Scsi_Host *instance)
1645         __releases(&hostdata->lock) __acquires(&hostdata->lock)
1646 {
1647         struct NCR5380_hostdata *hostdata = shost_priv(instance);
1648         unsigned char msgout = NOP;
1649         int sink = 0;
1650         int len;
1651         int transfersize;
1652         unsigned char *data;
1653         unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
1654         struct scsi_cmnd *cmd;
1655
1656 #ifdef SUN3_SCSI_VME
1657         dregs->csr |= CSR_INTR;
1658 #endif
1659
1660         while ((cmd = hostdata->connected)) {
1661                 struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);
1662
1663                 tmp = NCR5380_read(STATUS_REG);
1664                 /* We only have a valid SCSI phase when REQ is asserted */
1665                 if (tmp & SR_REQ) {
1666                         phase = (tmp & PHASE_MASK);
1667                         if (phase != old_phase) {
1668                                 old_phase = phase;
1669                                 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
1670                         }
1671 #ifdef CONFIG_SUN3
1672                         if (phase == PHASE_CMDOUT &&
1673                             sun3_dma_setup_done != cmd) {
1674                                 int count;
1675
1676                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
1677                                         ++cmd->SCp.buffer;
1678                                         --cmd->SCp.buffers_residual;
1679                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
1680                                         cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1681                                 }
1682
1683                                 count = sun3scsi_dma_xfer_len(hostdata, cmd);
1684
1685                                 if (count > 0) {
1686                                         if (rq_data_dir(cmd->request))
1687                                                 sun3scsi_dma_send_setup(hostdata,
1688                                                                         cmd->SCp.ptr, count);
1689                                         else
1690                                                 sun3scsi_dma_recv_setup(hostdata,
1691                                                                         cmd->SCp.ptr, count);
1692                                         sun3_dma_setup_done = cmd;
1693                                 }
1694 #ifdef SUN3_SCSI_VME
1695                                 dregs->csr |= CSR_INTR;
1696 #endif
1697                         }
1698 #endif /* CONFIG_SUN3 */
1699
1700                         if (sink && (phase != PHASE_MSGOUT)) {
1701                                 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1702
1703                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1704                                               ICR_ASSERT_ACK);
1705                                 while (NCR5380_read(STATUS_REG) & SR_REQ)
1706                                         ;
1707                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1708                                               ICR_ASSERT_ATN);
1709                                 sink = 0;
1710                                 continue;
1711                         }
1712
1713                         switch (phase) {
1714                         case PHASE_DATAOUT:
1715 #if (NDEBUG & NDEBUG_NO_DATAOUT)
1716                                 shost_printk(KERN_DEBUG, instance, "NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n");
1717                                 sink = 1;
1718                                 do_abort(instance);
1719                                 cmd->result = DID_ERROR << 16;
1720                                 complete_cmd(instance, cmd);
1721                                 hostdata->connected = NULL;
1722                                 hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
1723                                 return;
1724 #endif
1725                         case PHASE_DATAIN:
1726                                 /*
1727                                  * If there is no room left in the current buffer in the
1728                                  * scatter-gather list, move onto the next one.
1729                                  */
1730
1731                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
1732                                         ++cmd->SCp.buffer;
1733                                         --cmd->SCp.buffers_residual;
1734                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
1735                                         cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1736                                         dsprintk(NDEBUG_INFORMATION, instance, "%d bytes and %d buffers left\n",
1737                                                  cmd->SCp.this_residual,
1738                                                  cmd->SCp.buffers_residual);
1739                                 }
1740
1741                                 /*
1742                                  * The preferred transfer method is going to be
1743                                  * PSEUDO-DMA for systems that are strictly PIO,
1744                                  * since we can let the hardware do the handshaking.
1745                                  *
1746                                  * For this to work, we need to know the transfersize
1747                                  * ahead of time, since the pseudo-DMA code will sit
1748                                  * in an unconditional loop.
1749                                  */
1750
1751                                 transfersize = 0;
1752                                 if (!cmd->device->borken)
1753                                         transfersize = NCR5380_dma_xfer_len(hostdata, cmd);
1754
1755                                 if (transfersize > 0) {
1756                                         len = transfersize;
1757                                         if (NCR5380_transfer_dma(instance, &phase,
1758                                             &len, (unsigned char **)&cmd->SCp.ptr)) {
1759                                                 /*
1760                                                  * If the watchdog timer fires, all future
1761                                                  * accesses to this device will use the
1762                                                  * polled-IO.
1763                                                  */
1764                                                 scmd_printk(KERN_INFO, cmd,
1765                                                         "switching to slow handshake\n");
1766                                                 cmd->device->borken = 1;
1767                                                 sink = 1;
1768                                                 do_abort(instance);
1769                                                 cmd->result = DID_ERROR << 16;
1770                                                 /* XXX - need to source or sink data here, as appropriate */
1771                                         }
1772                                 } else {
1773                                         /* Transfer a small chunk so that the
1774                                          * irq mode lock is not held too long.
1775                                          */
1776                                         transfersize = min(cmd->SCp.this_residual,
1777                                                            NCR5380_PIO_CHUNK_SIZE);
1778                                         len = transfersize;
1779                                         NCR5380_transfer_pio(instance, &phase, &len,
1780                                                              (unsigned char **)&cmd->SCp.ptr);
1781                                         cmd->SCp.this_residual -= transfersize - len;
1782                                 }
1783 #ifdef CONFIG_SUN3
1784                                 if (sun3_dma_setup_done == cmd)
1785                                         sun3_dma_setup_done = NULL;
1786 #endif
1787                                 return;
1788                         case PHASE_MSGIN:
1789                                 len = 1;
1790                                 data = &tmp;
1791                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
1792                                 cmd->SCp.Message = tmp;
1793
1794                                 switch (tmp) {
1795                                 case ABORT:
1796                                 case COMMAND_COMPLETE:
1797                                         /* Accept message by clearing ACK */
1798                                         sink = 1;
1799                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1800                                         dsprintk(NDEBUG_QUEUES, instance,
1801                                                  "COMMAND COMPLETE %p target %d lun %llu\n",
1802                                                  cmd, scmd_id(cmd), cmd->device->lun);
1803
1804                                         hostdata->connected = NULL;
1805                                         hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
1806
1807                                         cmd->result &= ~0xffff;
1808                                         cmd->result |= cmd->SCp.Status;
1809                                         cmd->result |= cmd->SCp.Message << 8;
1810
1811                                         if (cmd->cmnd[0] == REQUEST_SENSE)
1812                                                 complete_cmd(instance, cmd);
1813                                         else {
1814                                                 if (cmd->SCp.Status == SAM_STAT_CHECK_CONDITION ||
1815                                                     cmd->SCp.Status == SAM_STAT_COMMAND_TERMINATED) {
1816                                                         dsprintk(NDEBUG_QUEUES, instance, "autosense: adding cmd %p to tail of autosense queue\n",
1817                                                                  cmd);
1818                                                         list_add_tail(&ncmd->list,
1819                                                                       &hostdata->autosense);
1820                                                 } else
1821                                                         complete_cmd(instance, cmd);
1822                                         }
1823
1824                                         /*
1825                                          * Restore phase bits to 0 so an interrupted selection,
1826                                          * arbitration can resume.
1827                                          */
1828                                         NCR5380_write(TARGET_COMMAND_REG, 0);
1829
1830                                         /* Enable reselect interrupts */
1831                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1832
1833                                         maybe_release_dma_irq(instance);
1834                                         return;
1835                                 case MESSAGE_REJECT:
1836                                         /* Accept message by clearing ACK */
1837                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1838                                         switch (hostdata->last_message) {
1839                                         case HEAD_OF_QUEUE_TAG:
1840                                         case ORDERED_QUEUE_TAG:
1841                                         case SIMPLE_QUEUE_TAG:
1842                                                 cmd->device->simple_tags = 0;
1843                                                 hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF));
1844                                                 break;
1845                                         default:
1846                                                 break;
1847                                         }
1848                                         break;
1849                                 case DISCONNECT:
1850                                         /* Accept message by clearing ACK */
1851                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1852                                         hostdata->connected = NULL;
1853                                         list_add(&ncmd->list, &hostdata->disconnected);
1854                                         dsprintk(NDEBUG_INFORMATION | NDEBUG_QUEUES,
1855                                                  instance, "connected command %p for target %d lun %llu moved to disconnected queue\n",
1856                                                  cmd, scmd_id(cmd), cmd->device->lun);
1857
1858                                         /*
1859                                          * Restore phase bits to 0 so an interrupted selection,
1860                                          * arbitration can resume.
1861                                          */
1862                                         NCR5380_write(TARGET_COMMAND_REG, 0);
1863
1864                                         /* Enable reselect interrupts */
1865                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1866 #ifdef SUN3_SCSI_VME
1867                                         dregs->csr |= CSR_DMA_ENABLE;
1868 #endif
1869                                         return;
1870                                         /*
1871                                          * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
1872                                          * operation, in violation of the SCSI spec so we can safely
1873                                          * ignore SAVE/RESTORE pointers calls.
1874                                          *
1875                                          * Unfortunately, some disks violate the SCSI spec and
1876                                          * don't issue the required SAVE_POINTERS message before
1877                                          * disconnecting, and we have to break spec to remain
1878                                          * compatible.
1879                                          */
1880                                 case SAVE_POINTERS:
1881                                 case RESTORE_POINTERS:
1882                                         /* Accept message by clearing ACK */
1883                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1884                                         break;
1885                                 case EXTENDED_MESSAGE:
1886                                         /*
1887                                          * Start the message buffer with the EXTENDED_MESSAGE
1888                                          * byte, since spi_print_msg() wants the whole thing.
1889                                          */
1890                                         extended_msg[0] = EXTENDED_MESSAGE;
1891                                         /* Accept first byte by clearing ACK */
1892                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1893
1894                                         spin_unlock_irq(&hostdata->lock);
1895
1896                                         dsprintk(NDEBUG_EXTENDED, instance, "receiving extended message\n");
1897
1898                                         len = 2;
1899                                         data = extended_msg + 1;
1900                                         phase = PHASE_MSGIN;
1901                                         NCR5380_transfer_pio(instance, &phase, &len, &data);
1902                                         dsprintk(NDEBUG_EXTENDED, instance, "length %d, code 0x%02x\n",
1903                                                  (int)extended_msg[1],
1904                                                  (int)extended_msg[2]);
1905
1906                                         if (!len && extended_msg[1] > 0 &&
1907                                             extended_msg[1] <= sizeof(extended_msg) - 2) {
1908                                                 /* Accept third byte by clearing ACK */
1909                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1910                                                 len = extended_msg[1] - 1;
1911                                                 data = extended_msg + 3;
1912                                                 phase = PHASE_MSGIN;
1913
1914                                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
1915                                                 dsprintk(NDEBUG_EXTENDED, instance, "message received, residual %d\n",
1916                                                          len);
1917
1918                                                 switch (extended_msg[2]) {
1919                                                 case EXTENDED_SDTR:
1920                                                 case EXTENDED_WDTR:
1921                                                         tmp = 0;
1922                                                 }
1923                                         } else if (len) {
1924                                                 shost_printk(KERN_ERR, instance, "error receiving extended message\n");
1925                                                 tmp = 0;
1926                                         } else {
1927                                                 shost_printk(KERN_NOTICE, instance, "extended message code %02x length %d is too long\n",
1928                                                              extended_msg[2], extended_msg[1]);
1929                                                 tmp = 0;
1930                                         }
1931
1932                                         spin_lock_irq(&hostdata->lock);
1933                                         if (!hostdata->connected)
1934                                                 return;
1935
1936                                         /* Fall through to reject message */
1937
1938                                         /*
1939                                          * If we get something weird that we aren't expecting,
1940                                          * reject it.
1941                                          */
1942                                 default:
1943                                         if (tmp == EXTENDED_MESSAGE)
1944                                                 scmd_printk(KERN_INFO, cmd,
1945                                                             "rejecting unknown extended message code %02x, length %d\n",
1946                                                             extended_msg[2], extended_msg[1]);
1947                                         else if (tmp)
1948                                                 scmd_printk(KERN_INFO, cmd,
1949                                                             "rejecting unknown message code %02x\n",
1950                                                             tmp);
1951
1952                                         msgout = MESSAGE_REJECT;
1953                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1954                                         break;
1955                                 } /* switch (tmp) */
1956                                 break;
1957                         case PHASE_MSGOUT:
1958                                 len = 1;
1959                                 data = &msgout;
1960                                 hostdata->last_message = msgout;
1961                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
1962                                 if (msgout == ABORT) {
1963                                         hostdata->connected = NULL;
1964                                         hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
1965                                         cmd->result = DID_ERROR << 16;
1966                                         complete_cmd(instance, cmd);
1967                                         maybe_release_dma_irq(instance);
1968                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1969                                         return;
1970                                 }
1971                                 msgout = NOP;
1972                                 break;
1973                         case PHASE_CMDOUT:
1974                                 len = cmd->cmd_len;
1975                                 data = cmd->cmnd;
1976                                 /*
1977                                  * XXX for performance reasons, on machines with a
1978                                  * PSEUDO-DMA architecture we should probably
1979                                  * use the dma transfer function.
1980                                  */
1981                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
1982                                 break;
1983                         case PHASE_STATIN:
1984                                 len = 1;
1985                                 data = &tmp;
1986                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
1987                                 cmd->SCp.Status = tmp;
1988                                 break;
1989                         default:
1990                                 shost_printk(KERN_ERR, instance, "unknown phase\n");
1991                                 NCR5380_dprint(NDEBUG_ANY, instance);
1992                         } /* switch(phase) */
1993                 } else {
1994                         spin_unlock_irq(&hostdata->lock);
1995                         NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ);
1996                         spin_lock_irq(&hostdata->lock);
1997                 }
1998         }
1999 }
2000
2001 /*
2002  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2003  *
2004  * Purpose : does reselection, initializing the instance->connected
2005  * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
2006  * nexus has been reestablished,
2007  *
2008  * Inputs : instance - this instance of the NCR5380.
2009  */
2010
2011 static void NCR5380_reselect(struct Scsi_Host *instance)
2012 {
2013         struct NCR5380_hostdata *hostdata = shost_priv(instance);
2014         unsigned char target_mask;
2015         unsigned char lun;
2016         unsigned char msg[3];
2017         struct NCR5380_cmd *ncmd;
2018         struct scsi_cmnd *tmp;
2019
2020         /*
2021          * Disable arbitration, etc. since the host adapter obviously
2022          * lost, and tell an interrupted NCR5380_select() to restart.
2023          */
2024
2025         NCR5380_write(MODE_REG, MR_BASE);
2026
2027         target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2028         if (!target_mask || target_mask & (target_mask - 1)) {
2029                 shost_printk(KERN_WARNING, instance,
2030                              "reselect: bad target_mask 0x%02x\n", target_mask);
2031                 return;
2032         }
2033
2034         /*
2035          * At this point, we have detected that our SCSI ID is on the bus,
2036          * SEL is true and BSY was false for at least one bus settle delay
2037          * (400 ns).
2038          *
2039          * We must assert BSY ourselves, until the target drops the SEL
2040          * signal.
2041          */
2042
2043         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2044         if (NCR5380_poll_politely(hostdata,
2045                                   STATUS_REG, SR_SEL, 0, 2 * HZ) < 0) {
2046                 shost_printk(KERN_ERR, instance, "reselect: !SEL timeout\n");
2047                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2048                 return;
2049         }
2050         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2051
2052         /*
2053          * Wait for target to go into MSGIN.
2054          */
2055
2056         if (NCR5380_poll_politely(hostdata,
2057                                   STATUS_REG, SR_REQ, SR_REQ, 2 * HZ) < 0) {
2058                 if ((NCR5380_read(STATUS_REG) & (SR_BSY | SR_SEL)) == 0)
2059                         /* BUS FREE phase */
2060                         return;
2061                 shost_printk(KERN_ERR, instance, "reselect: REQ timeout\n");
2062                 do_abort(instance);
2063                 return;
2064         }
2065
2066 #ifdef CONFIG_SUN3
2067         /* acknowledge toggle to MSGIN */
2068         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));
2069
2070         /* peek at the byte without really hitting the bus */
2071         msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG);
2072 #else
2073         {
2074                 int len = 1;
2075                 unsigned char *data = msg;
2076                 unsigned char phase = PHASE_MSGIN;
2077
2078                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2079
2080                 if (len) {
2081                         do_abort(instance);
2082                         return;
2083                 }
2084         }
2085 #endif /* CONFIG_SUN3 */
2086
2087         if (!(msg[0] & 0x80)) {
2088                 shost_printk(KERN_ERR, instance, "expecting IDENTIFY message, got ");
2089                 spi_print_msg(msg);
2090                 printk("\n");
2091                 do_abort(instance);
2092                 return;
2093         }
2094         lun = msg[0] & 0x07;
2095
2096         /*
2097          * We need to add code for SCSI-II to track which devices have
2098          * I_T_L_Q nexuses established, and which have simple I_T_L
2099          * nexuses so we can chose to do additional data transfer.
2100          */
2101
2102         /*
2103          * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we
2104          * just reestablished, and remove it from the disconnected queue.
2105          */
2106
2107         tmp = NULL;
2108         list_for_each_entry(ncmd, &hostdata->disconnected, list) {
2109                 struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd);
2110
2111                 if (target_mask == (1 << scmd_id(cmd)) &&
2112                     lun == (u8)cmd->device->lun) {
2113                         list_del(&ncmd->list);
2114                         tmp = cmd;
2115                         break;
2116                 }
2117         }
2118
2119         if (tmp) {
2120                 dsprintk(NDEBUG_RESELECTION | NDEBUG_QUEUES, instance,
2121                          "reselect: removed %p from disconnected queue\n", tmp);
2122         } else {
2123                 int target = ffs(target_mask) - 1;
2124
2125                 shost_printk(KERN_ERR, instance, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
2126                              target_mask, lun);
2127                 /*
2128                  * Since we have an established nexus that we can't do anything
2129                  * with, we must abort it.
2130                  */
2131                 if (do_abort(instance) == 0)
2132                         hostdata->busy[target] &= ~(1 << lun);
2133                 return;
2134         }
2135
2136 #ifdef CONFIG_SUN3
2137         if (sun3_dma_setup_done != tmp) {
2138                 int count;
2139
2140                 if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
2141                         ++tmp->SCp.buffer;
2142                         --tmp->SCp.buffers_residual;
2143                         tmp->SCp.this_residual = tmp->SCp.buffer->length;
2144                         tmp->SCp.ptr = sg_virt(tmp->SCp.buffer);
2145                 }
2146
2147                 count = sun3scsi_dma_xfer_len(hostdata, tmp);
2148
2149                 if (count > 0) {
2150                         if (rq_data_dir(tmp->request))
2151                                 sun3scsi_dma_send_setup(hostdata,
2152                                                         tmp->SCp.ptr, count);
2153                         else
2154                                 sun3scsi_dma_recv_setup(hostdata,
2155                                                         tmp->SCp.ptr, count);
2156                         sun3_dma_setup_done = tmp;
2157                 }
2158         }
2159
2160         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
2161 #endif /* CONFIG_SUN3 */
2162
2163         /* Accept message by clearing ACK */
2164         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2165
2166         hostdata->connected = tmp;
2167         dsprintk(NDEBUG_RESELECTION, instance, "nexus established, target %d, lun %llu\n",
2168                  scmd_id(tmp), tmp->device->lun);
2169 }
2170
2171 /**
2172  * list_find_cmd - test for presence of a command in a linked list
2173  * @haystack: list of commands
2174  * @needle: command to search for
2175  */
2176
2177 static bool list_find_cmd(struct list_head *haystack,
2178                           struct scsi_cmnd *needle)
2179 {
2180         struct NCR5380_cmd *ncmd;
2181
2182         list_for_each_entry(ncmd, haystack, list)
2183                 if (NCR5380_to_scmd(ncmd) == needle)
2184                         return true;
2185         return false;
2186 }
2187
2188 /**
2189  * list_remove_cmd - remove a command from linked list
2190  * @haystack: list of commands
2191  * @needle: command to remove
2192  */
2193
2194 static bool list_del_cmd(struct list_head *haystack,
2195                          struct scsi_cmnd *needle)
2196 {
2197         if (list_find_cmd(haystack, needle)) {
2198                 struct NCR5380_cmd *ncmd = scsi_cmd_priv(needle);
2199
2200                 list_del(&ncmd->list);
2201                 return true;
2202         }
2203         return false;
2204 }
2205
2206 /**
2207  * NCR5380_abort - scsi host eh_abort_handler() method
2208  * @cmd: the command to be aborted
2209  *
2210  * Try to abort a given command by removing it from queues and/or sending
2211  * the target an abort message. This may not succeed in causing a target
2212  * to abort the command. Nonetheless, the low-level driver must forget about
2213  * the command because the mid-layer reclaims it and it may be re-issued.
2214  *
2215  * The normal path taken by a command is as follows. For EH we trace this
2216  * same path to locate and abort the command.
2217  *
2218  * unissued -> selecting -> [unissued -> selecting ->]... connected ->
2219  * [disconnected -> connected ->]...
2220  * [autosense -> connected ->] done
2221  *
2222  * If cmd was not found at all then presumably it has already been completed,
2223  * in which case return SUCCESS to try to avoid further EH measures.
2224  *
2225  * If the command has not completed yet, we must not fail to find it.
2226  * We have no option but to forget the aborted command (even if it still
2227  * lacks sense data). The mid-layer may re-issue a command that is in error
2228  * recovery (see scsi_send_eh_cmnd), but the logic and data structures in
2229  * this driver are such that a command can appear on one queue only.
2230  *
2231  * The lock protects driver data structures, but EH handlers also use it
2232  * to serialize their own execution and prevent their own re-entry.
2233  */
2234
2235 static int NCR5380_abort(struct scsi_cmnd *cmd)
2236 {
2237         struct Scsi_Host *instance = cmd->device->host;
2238         struct NCR5380_hostdata *hostdata = shost_priv(instance);
2239         unsigned long flags;
2240         int result = SUCCESS;
2241
2242         spin_lock_irqsave(&hostdata->lock, flags);
2243
2244 #if (NDEBUG & NDEBUG_ANY)
2245         scmd_printk(KERN_INFO, cmd, __func__);
2246 #endif
2247         NCR5380_dprint(NDEBUG_ANY, instance);
2248         NCR5380_dprint_phase(NDEBUG_ANY, instance);
2249
2250         if (list_del_cmd(&hostdata->unissued, cmd)) {
2251                 dsprintk(NDEBUG_ABORT, instance,
2252                          "abort: removed %p from issue queue\n", cmd);
2253                 cmd->result = DID_ABORT << 16;
2254                 cmd->scsi_done(cmd); /* No tag or busy flag to worry about */
2255                 goto out;
2256         }
2257
2258         if (hostdata->selecting == cmd) {
2259                 dsprintk(NDEBUG_ABORT, instance,
2260                          "abort: cmd %p == selecting\n", cmd);
2261                 hostdata->selecting = NULL;
2262                 cmd->result = DID_ABORT << 16;
2263                 complete_cmd(instance, cmd);
2264                 goto out;
2265         }
2266
2267         if (list_del_cmd(&hostdata->disconnected, cmd)) {
2268                 dsprintk(NDEBUG_ABORT, instance,
2269                          "abort: removed %p from disconnected list\n", cmd);
2270                 /* Can't call NCR5380_select() and send ABORT because that
2271                  * means releasing the lock. Need a bus reset.
2272                  */
2273                 set_host_byte(cmd, DID_ERROR);
2274                 complete_cmd(instance, cmd);
2275                 result = FAILED;
2276                 goto out;
2277         }
2278
2279         if (hostdata->connected == cmd) {
2280                 dsprintk(NDEBUG_ABORT, instance, "abort: cmd %p is connected\n", cmd);
2281                 hostdata->connected = NULL;
2282                 hostdata->dma_len = 0;
2283                 if (do_abort(instance)) {
2284                         set_host_byte(cmd, DID_ERROR);
2285                         complete_cmd(instance, cmd);
2286                         result = FAILED;
2287                         goto out;
2288                 }
2289                 set_host_byte(cmd, DID_ABORT);
2290                 complete_cmd(instance, cmd);
2291                 goto out;
2292         }
2293
2294         if (list_del_cmd(&hostdata->autosense, cmd)) {
2295                 dsprintk(NDEBUG_ABORT, instance,
2296                          "abort: removed %p from sense queue\n", cmd);
2297                 complete_cmd(instance, cmd);
2298         }
2299
2300 out:
2301         if (result == FAILED)
2302                 dsprintk(NDEBUG_ABORT, instance, "abort: failed to abort %p\n", cmd);
2303         else {
2304                 hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
2305                 dsprintk(NDEBUG_ABORT, instance, "abort: successfully aborted %p\n", cmd);
2306         }
2307
2308         queue_work(hostdata->work_q, &hostdata->main_task);
2309         maybe_release_dma_irq(instance);
2310         spin_unlock_irqrestore(&hostdata->lock, flags);
2311
2312         return result;
2313 }
2314
2315
2316 static void bus_reset_cleanup(struct Scsi_Host *instance)
2317 {
2318         struct NCR5380_hostdata *hostdata = shost_priv(instance);
2319         int i;
2320         struct NCR5380_cmd *ncmd;
2321
2322         /* reset NCR registers */
2323         NCR5380_write(MODE_REG, MR_BASE);
2324         NCR5380_write(TARGET_COMMAND_REG, 0);
2325         NCR5380_write(SELECT_ENABLE_REG, 0);
2326
2327         /* After the reset, there are no more connected or disconnected commands
2328          * and no busy units; so clear the low-level status here to avoid
2329          * conflicts when the mid-level code tries to wake up the affected
2330          * commands!
2331          */
2332
2333         if (hostdata->selecting) {
2334                 hostdata->selecting->result = DID_RESET << 16;
2335                 complete_cmd(instance, hostdata->selecting);
2336                 hostdata->selecting = NULL;
2337         }
2338
2339         list_for_each_entry(ncmd, &hostdata->disconnected, list) {
2340                 struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd);
2341
2342                 set_host_byte(cmd, DID_RESET);
2343                 complete_cmd(instance, cmd);
2344         }
2345         INIT_LIST_HEAD(&hostdata->disconnected);
2346
2347         list_for_each_entry(ncmd, &hostdata->autosense, list) {
2348                 struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd);
2349
2350                 cmd->scsi_done(cmd);
2351         }
2352         INIT_LIST_HEAD(&hostdata->autosense);
2353
2354         if (hostdata->connected) {
2355                 set_host_byte(hostdata->connected, DID_RESET);
2356                 complete_cmd(instance, hostdata->connected);
2357                 hostdata->connected = NULL;
2358         }
2359
2360         for (i = 0; i < 8; ++i)
2361                 hostdata->busy[i] = 0;
2362         hostdata->dma_len = 0;
2363
2364         queue_work(hostdata->work_q, &hostdata->main_task);
2365         maybe_release_dma_irq(instance);
2366 }
2367
2368 /**
2369  * NCR5380_host_reset - reset the SCSI host
2370  * @cmd: SCSI command undergoing EH
2371  *
2372  * Returns SUCCESS
2373  */
2374
2375 static int NCR5380_host_reset(struct scsi_cmnd *cmd)
2376 {
2377         struct Scsi_Host *instance = cmd->device->host;
2378         struct NCR5380_hostdata *hostdata = shost_priv(instance);
2379         unsigned long flags;
2380         struct NCR5380_cmd *ncmd;
2381
2382         spin_lock_irqsave(&hostdata->lock, flags);
2383
2384 #if (NDEBUG & NDEBUG_ANY)
2385         shost_printk(KERN_INFO, instance, __func__);
2386 #endif
2387         NCR5380_dprint(NDEBUG_ANY, instance);
2388         NCR5380_dprint_phase(NDEBUG_ANY, instance);
2389
2390         list_for_each_entry(ncmd, &hostdata->unissued, list) {
2391                 struct scsi_cmnd *scmd = NCR5380_to_scmd(ncmd);
2392
2393                 scmd->result = DID_RESET << 16;
2394                 scmd->scsi_done(scmd);
2395         }
2396         INIT_LIST_HEAD(&hostdata->unissued);
2397
2398         do_reset(instance);
2399         bus_reset_cleanup(instance);
2400
2401         spin_unlock_irqrestore(&hostdata->lock, flags);
2402
2403         return SUCCESS;
2404 }