linux/drivers/scsi/NCR5380.c
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   1/* 
   2 * NCR 5380 generic driver routines.  These should make it *trivial*
   3 *      to implement 5380 SCSI drivers under Linux with a non-trantor
   4 *      architecture.
   5 *
   6 *      Note that these routines also work with NR53c400 family chips.
   7 *
   8 * Copyright 1993, Drew Eckhardt
   9 *      Visionary Computing 
  10 *      (Unix and Linux consulting and custom programming)
  11 *      drew@colorado.edu
  12 *      +1 (303) 666-5836
  13 *
  14 * DISTRIBUTION RELEASE 6. 
  15 *
  16 * For more information, please consult 
  17 *
  18 * NCR 5380 Family
  19 * SCSI Protocol Controller
  20 * Databook
  21 *
  22 * NCR Microelectronics
  23 * 1635 Aeroplaza Drive
  24 * Colorado Springs, CO 80916
  25 * 1+ (719) 578-3400
  26 * 1+ (800) 334-5454
  27 */
  28
  29/*
  30 * $Log: NCR5380.c,v $
  31
  32 * Revision 1.10 1998/9/2       Alan Cox
  33 *                              (alan@lxorguk.ukuu.org.uk)
  34 * Fixed up the timer lockups reported so far. Things still suck. Looking 
  35 * forward to 2.3 and per device request queues. Then it'll be possible to
  36 * SMP thread this beast and improve life no end.
  37 
  38 * Revision 1.9  1997/7/27      Ronald van Cuijlenborg
  39 *                              (ronald.van.cuijlenborg@tip.nl or nutty@dds.nl)
  40 * (hopefully) fixed and enhanced USLEEP
  41 * added support for DTC3181E card (for Mustek scanner)
  42 *
  43
  44 * Revision 1.8                 Ingmar Baumgart
  45 *                              (ingmar@gonzo.schwaben.de)
  46 * added support for NCR53C400a card
  47 *
  48
  49 * Revision 1.7  1996/3/2       Ray Van Tassle (rayvt@comm.mot.com)
  50 * added proc_info
  51 * added support needed for DTC 3180/3280
  52 * fixed a couple of bugs
  53 *
  54
  55 * Revision 1.5  1994/01/19  09:14:57  drew
  56 * Fixed udelay() hack that was being used on DATAOUT phases
  57 * instead of a proper wait for the final handshake.
  58 *
  59 * Revision 1.4  1994/01/19  06:44:25  drew
  60 * *** empty log message ***
  61 *
  62 * Revision 1.3  1994/01/19  05:24:40  drew
  63 * Added support for TCR LAST_BYTE_SENT bit.
  64 *
  65 * Revision 1.2  1994/01/15  06:14:11  drew
  66 * REAL DMA support, bug fixes.
  67 *
  68 * Revision 1.1  1994/01/15  06:00:54  drew
  69 * Initial revision
  70 *
  71 */
  72
  73/*
  74 * Further development / testing that should be done : 
  75 * 1.  Cleanup the NCR5380_transfer_dma function and DMA operation complete
  76 *     code so that everything does the same thing that's done at the 
  77 *     end of a pseudo-DMA read operation.
  78 *
  79 * 2.  Fix REAL_DMA (interrupt driven, polled works fine) -
  80 *     basically, transfer size needs to be reduced by one 
  81 *     and the last byte read as is done with PSEUDO_DMA.
  82 * 
  83 * 4.  Test SCSI-II tagged queueing (I have no devices which support 
  84 *      tagged queueing)
  85 *
  86 * 5.  Test linked command handling code after Eric is ready with 
  87 *      the high level code.
  88 */
  89#include <scsi/scsi_dbg.h>
  90#include <scsi/scsi_transport_spi.h>
  91
  92#ifndef NDEBUG
  93#define NDEBUG 0
  94#endif
  95#ifndef NDEBUG_ABORT
  96#define NDEBUG_ABORT 0
  97#endif
  98
  99#if (NDEBUG & NDEBUG_LISTS)
 100#define LIST(x,y) {printk("LINE:%d   Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); if ((x)==(y)) udelay(5); }
 101#define REMOVE(w,x,y,z) {printk("LINE:%d   Removing: %p->%p  %p->%p \n", __LINE__, (void*)(w), (void*)(x), (void*)(y), (void*)(z)); if ((x)==(y)) udelay(5); }
 102#else
 103#define LIST(x,y)
 104#define REMOVE(w,x,y,z)
 105#endif
 106
 107#ifndef notyet
 108#undef LINKED
 109#undef REAL_DMA
 110#endif
 111
 112#ifdef REAL_DMA_POLL
 113#undef READ_OVERRUNS
 114#define READ_OVERRUNS
 115#endif
 116
 117#ifdef BOARD_REQUIRES_NO_DELAY
 118#define io_recovery_delay(x)
 119#else
 120#define io_recovery_delay(x)    udelay(x)
 121#endif
 122
 123/*
 124 * Design
 125 *
 126 * This is a generic 5380 driver.  To use it on a different platform, 
 127 * one simply writes appropriate system specific macros (ie, data
 128 * transfer - some PC's will use the I/O bus, 68K's must use 
 129 * memory mapped) and drops this file in their 'C' wrapper.
 130 *
 131 * (Note from hch:  unfortunately it was not enough for the different
 132 * m68k folks and instead of improving this driver they copied it
 133 * and hacked it up for their needs.  As a consequence they lost
 134 * most updates to this driver.  Maybe someone will fix all these
 135 * drivers to use a common core one day..)
 136 *
 137 * As far as command queueing, two queues are maintained for 
 138 * each 5380 in the system - commands that haven't been issued yet,
 139 * and commands that are currently executing.  This means that an 
 140 * unlimited number of commands may be queued, letting 
 141 * more commands propagate from the higher driver levels giving higher 
 142 * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported, 
 143 * allowing multiple commands to propagate all the way to a SCSI-II device 
 144 * while a command is already executing.
 145 *
 146 *
 147 * Issues specific to the NCR5380 : 
 148 *
 149 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 
 150 * piece of hardware that requires you to sit in a loop polling for 
 151 * the REQ signal as long as you are connected.  Some devices are 
 152 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 
 153 * while doing long seek operations.
 154 * 
 155 * The workaround for this is to keep track of devices that have
 156 * disconnected.  If the device hasn't disconnected, for commands that
 157 * should disconnect, we do something like 
 158 *
 159 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
 160 * 
 161 * Some tweaking of N and M needs to be done.  An algorithm based 
 162 * on "time to data" would give the best results as long as short time
 163 * to datas (ie, on the same track) were considered, however these 
 164 * broken devices are the exception rather than the rule and I'd rather
 165 * spend my time optimizing for the normal case.
 166 *
 167 * Architecture :
 168 *
 169 * At the heart of the design is a coroutine, NCR5380_main,
 170 * which is started from a workqueue for each NCR5380 host in the
 171 * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
 172 * removing the commands from the issue queue and calling
 173 * NCR5380_select() if a nexus is not established. 
 174 *
 175 * Once a nexus is established, the NCR5380_information_transfer()
 176 * phase goes through the various phases as instructed by the target.
 177 * if the target goes into MSG IN and sends a DISCONNECT message,
 178 * the command structure is placed into the per instance disconnected
 179 * queue, and NCR5380_main tries to find more work.  If the target is 
 180 * idle for too long, the system will try to sleep.
 181 *
 182 * If a command has disconnected, eventually an interrupt will trigger,
 183 * calling NCR5380_intr()  which will in turn call NCR5380_reselect
 184 * to reestablish a nexus.  This will run main if necessary.
 185 *
 186 * On command termination, the done function will be called as 
 187 * appropriate.
 188 *
 189 * SCSI pointers are maintained in the SCp field of SCSI command 
 190 * structures, being initialized after the command is connected
 191 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
 192 * Note that in violation of the standard, an implicit SAVE POINTERS operation
 193 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
 194 */
 195
 196/*
 197 * Using this file :
 198 * This file a skeleton Linux SCSI driver for the NCR 5380 series
 199 * of chips.  To use it, you write an architecture specific functions 
 200 * and macros and include this file in your driver.
 201 *
 202 * These macros control options : 
 203 * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be 
 204 *      defined.
 205 * 
 206 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
 207 *      for commands that return with a CHECK CONDITION status. 
 208 *
 209 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
 210 *      transceivers. 
 211 *
 212 * DONT_USE_INTR - if defined, never use interrupts, even if we probe or
 213 *      override-configure an IRQ.
 214 *
 215 * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512
 216 *      bytes at a time.  Since interrupts are disabled by default during
 217 *      these transfers, we might need this to give reasonable interrupt
 218 *      service time if the transfer size gets too large.
 219 *
 220 * LINKED - if defined, linked commands are supported.
 221 *
 222 * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
 223 *
 224 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
 225 *
 226 * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't
 227 *      rely on phase mismatch and EOP interrupts to determine end 
 228 *      of phase.
 229 *
 230 * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  You
 231 *          only really want to use this if you're having a problem with
 232 *          dropped characters during high speed communications, and even
 233 *          then, you're going to be better off twiddling with transfersize
 234 *          in the high level code.
 235 *
 236 * Defaults for these will be provided although the user may want to adjust 
 237 * these to allocate CPU resources to the SCSI driver or "real" code.
 238 * 
 239 * USLEEP_SLEEP - amount of time, in jiffies, to sleep
 240 *
 241 * USLEEP_POLL - amount of time, in jiffies, to poll
 242 *
 243 * These macros MUST be defined :
 244 * NCR5380_local_declare() - declare any local variables needed for your
 245 *      transfer routines.
 246 *
 247 * NCR5380_setup(instance) - initialize any local variables needed from a given
 248 *      instance of the host adapter for NCR5380_{read,write,pread,pwrite}
 249 * 
 250 * NCR5380_read(register)  - read from the specified register
 251 *
 252 * NCR5380_write(register, value) - write to the specific register 
 253 *
 254 * NCR5380_implementation_fields  - additional fields needed for this 
 255 *      specific implementation of the NCR5380
 256 *
 257 * Either real DMA *or* pseudo DMA may be implemented
 258 * REAL functions : 
 259 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
 260 * Note that the DMA setup functions should return the number of bytes 
 261 *      that they were able to program the controller for.
 262 *
 263 * Also note that generic i386/PC versions of these macros are 
 264 *      available as NCR5380_i386_dma_write_setup,
 265 *      NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
 266 *
 267 * NCR5380_dma_write_setup(instance, src, count) - initialize
 268 * NCR5380_dma_read_setup(instance, dst, count) - initialize
 269 * NCR5380_dma_residual(instance); - residual count
 270 *
 271 * PSEUDO functions :
 272 * NCR5380_pwrite(instance, src, count)
 273 * NCR5380_pread(instance, dst, count);
 274 *
 275 * The generic driver is initialized by calling NCR5380_init(instance),
 276 * after setting the appropriate host specific fields and ID.  If the 
 277 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
 278 * possible) function may be used.
 279 */
 280
 281static int do_abort(struct Scsi_Host *host);
 282static void do_reset(struct Scsi_Host *host);
 283
 284/*
 285 *      initialize_SCp          -       init the scsi pointer field
 286 *      @cmd: command block to set up
 287 *
 288 *      Set up the internal fields in the SCSI command.
 289 */
 290
 291static __inline__ void initialize_SCp(Scsi_Cmnd * cmd)
 292{
 293        /* 
 294         * Initialize the Scsi Pointer field so that all of the commands in the 
 295         * various queues are valid.
 296         */
 297
 298        if (scsi_bufflen(cmd)) {
 299                cmd->SCp.buffer = scsi_sglist(cmd);
 300                cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
 301                cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
 302                cmd->SCp.this_residual = cmd->SCp.buffer->length;
 303        } else {
 304                cmd->SCp.buffer = NULL;
 305                cmd->SCp.buffers_residual = 0;
 306                cmd->SCp.ptr = NULL;
 307                cmd->SCp.this_residual = 0;
 308        }
 309}
 310
 311/**
 312 *      NCR5380_poll_politely   -       wait for NCR5380 status bits
 313 *      @instance: controller to poll
 314 *      @reg: 5380 register to poll
 315 *      @bit: Bitmask to check
 316 *      @val: Value required to exit
 317 *
 318 *      Polls the NCR5380 in a reasonably efficient manner waiting for
 319 *      an event to occur, after a short quick poll we begin giving the
 320 *      CPU back in non IRQ contexts
 321 *
 322 *      Returns the value of the register or a negative error code.
 323 */
 324 
 325static int NCR5380_poll_politely(struct Scsi_Host *instance, int reg, int bit, int val, int t)
 326{
 327        NCR5380_local_declare();
 328        int n = 500;            /* At about 8uS a cycle for the cpu access */
 329        unsigned long end = jiffies + t;
 330        int r;
 331        
 332        NCR5380_setup(instance);
 333
 334        while( n-- > 0)
 335        {
 336                r = NCR5380_read(reg);
 337                if((r & bit) == val)
 338                        return 0;
 339                cpu_relax();
 340        }
 341        
 342        /* t time yet ? */
 343        while(time_before(jiffies, end))
 344        {
 345                r = NCR5380_read(reg);
 346                if((r & bit) == val)
 347                        return 0;
 348                if(!in_interrupt())
 349                        cond_resched();
 350                else
 351                        cpu_relax();
 352        }
 353        return -ETIMEDOUT;
 354}
 355
 356static struct {
 357        unsigned char value;
 358        const char *name;
 359} phases[] __maybe_unused = {
 360        {PHASE_DATAOUT, "DATAOUT"}, 
 361        {PHASE_DATAIN, "DATAIN"}, 
 362        {PHASE_CMDOUT, "CMDOUT"}, 
 363        {PHASE_STATIN, "STATIN"}, 
 364        {PHASE_MSGOUT, "MSGOUT"}, 
 365        {PHASE_MSGIN, "MSGIN"}, 
 366        {PHASE_UNKNOWN, "UNKNOWN"}
 367};
 368
 369#if NDEBUG
 370static struct {
 371        unsigned char mask;
 372        const char *name;
 373} signals[] = { 
 374        {SR_DBP, "PARITY"}, 
 375        {SR_RST, "RST"}, 
 376        {SR_BSY, "BSY"}, 
 377        {SR_REQ, "REQ"}, 
 378        {SR_MSG, "MSG"}, 
 379        {SR_CD, "CD"}, 
 380        {SR_IO, "IO"}, 
 381        {SR_SEL, "SEL"}, 
 382        {0, NULL}
 383}, 
 384basrs[] = {
 385        {BASR_ATN, "ATN"}, 
 386        {BASR_ACK, "ACK"}, 
 387        {0, NULL}
 388}, 
 389icrs[] = { 
 390        {ICR_ASSERT_RST, "ASSERT RST"}, 
 391        {ICR_ASSERT_ACK, "ASSERT ACK"}, 
 392        {ICR_ASSERT_BSY, "ASSERT BSY"}, 
 393        {ICR_ASSERT_SEL, "ASSERT SEL"}, 
 394        {ICR_ASSERT_ATN, "ASSERT ATN"}, 
 395        {ICR_ASSERT_DATA, "ASSERT DATA"}, 
 396        {0, NULL}
 397}, 
 398mrs[] = { 
 399        {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, 
 400        {MR_TARGET, "MODE TARGET"}, 
 401        {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, 
 402        {MR_ENABLE_PAR_INTR, "MODE PARITY INTR"}, 
 403        {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 
 404        {MR_DMA_MODE, "MODE DMA"}, 
 405        {MR_ARBITRATE, "MODE ARBITRATION"}, 
 406        {0, NULL}
 407};
 408
 409/**
 410 *      NCR5380_print   -       print scsi bus signals
 411 *      @instance:      adapter state to dump
 412 *
 413 *      Print the SCSI bus signals for debugging purposes
 414 *
 415 *      Locks: caller holds hostdata lock (not essential)
 416 */
 417
 418static void NCR5380_print(struct Scsi_Host *instance)
 419{
 420        NCR5380_local_declare();
 421        unsigned char status, data, basr, mr, icr, i;
 422        NCR5380_setup(instance);
 423
 424        data = NCR5380_read(CURRENT_SCSI_DATA_REG);
 425        status = NCR5380_read(STATUS_REG);
 426        mr = NCR5380_read(MODE_REG);
 427        icr = NCR5380_read(INITIATOR_COMMAND_REG);
 428        basr = NCR5380_read(BUS_AND_STATUS_REG);
 429
 430        printk("STATUS_REG: %02x ", status);
 431        for (i = 0; signals[i].mask; ++i)
 432                if (status & signals[i].mask)
 433                        printk(",%s", signals[i].name);
 434        printk("\nBASR: %02x ", basr);
 435        for (i = 0; basrs[i].mask; ++i)
 436                if (basr & basrs[i].mask)
 437                        printk(",%s", basrs[i].name);
 438        printk("\nICR: %02x ", icr);
 439        for (i = 0; icrs[i].mask; ++i)
 440                if (icr & icrs[i].mask)
 441                        printk(",%s", icrs[i].name);
 442        printk("\nMODE: %02x ", mr);
 443        for (i = 0; mrs[i].mask; ++i)
 444                if (mr & mrs[i].mask)
 445                        printk(",%s", mrs[i].name);
 446        printk("\n");
 447}
 448
 449
 450/* 
 451 *      NCR5380_print_phase     -       show SCSI phase
 452 *      @instance: adapter to dump
 453 *
 454 *      Print the current SCSI phase for debugging purposes
 455 *
 456 *      Locks: none
 457 */
 458
 459static void NCR5380_print_phase(struct Scsi_Host *instance)
 460{
 461        NCR5380_local_declare();
 462        unsigned char status;
 463        int i;
 464        NCR5380_setup(instance);
 465
 466        status = NCR5380_read(STATUS_REG);
 467        if (!(status & SR_REQ))
 468                printk("scsi%d : REQ not asserted, phase unknown.\n", instance->host_no);
 469        else {
 470                for (i = 0; (phases[i].value != PHASE_UNKNOWN) && (phases[i].value != (status & PHASE_MASK)); ++i);
 471                printk("scsi%d : phase %s\n", instance->host_no, phases[i].name);
 472        }
 473}
 474#endif
 475
 476/*
 477 * These need tweaking, and would probably work best as per-device 
 478 * flags initialized differently for disk, tape, cd, etc devices.
 479 * People with broken devices are free to experiment as to what gives
 480 * the best results for them.
 481 *
 482 * USLEEP_SLEEP should be a minimum seek time.
 483 *
 484 * USLEEP_POLL should be a maximum rotational latency.
 485 */
 486#ifndef USLEEP_SLEEP
 487/* 20 ms (reasonable hard disk speed) */
 488#define USLEEP_SLEEP (20*HZ/1000)
 489#endif
 490/* 300 RPM (floppy speed) */
 491#ifndef USLEEP_POLL
 492#define USLEEP_POLL (200*HZ/1000)
 493#endif
 494#ifndef USLEEP_WAITLONG
 495/* RvC: (reasonable time to wait on select error) */
 496#define USLEEP_WAITLONG USLEEP_SLEEP
 497#endif
 498
 499/* 
 500 * Function : int should_disconnect (unsigned char cmd)
 501 *
 502 * Purpose : decide whether a command would normally disconnect or 
 503 *      not, since if it won't disconnect we should go to sleep.
 504 *
 505 * Input : cmd - opcode of SCSI command
 506 *
 507 * Returns : DISCONNECT_LONG if we should disconnect for a really long 
 508 *      time (ie always, sleep, look for REQ active, sleep), 
 509 *      DISCONNECT_TIME_TO_DATA if we would only disconnect for a normal
 510 *      time-to-data delay, DISCONNECT_NONE if this command would return
 511 *      immediately.
 512 *
 513 *      Future sleep algorithms based on time to data can exploit 
 514 *      something like this so they can differentiate between "normal" 
 515 *      (ie, read, write, seek) and unusual commands (ie, * format).
 516 *
 517 * Note : We don't deal with commands that handle an immediate disconnect,
 518 *        
 519 */
 520
 521static int should_disconnect(unsigned char cmd)
 522{
 523        switch (cmd) {
 524        case READ_6:
 525        case WRITE_6:
 526        case SEEK_6:
 527        case READ_10:
 528        case WRITE_10:
 529        case SEEK_10:
 530                return DISCONNECT_TIME_TO_DATA;
 531        case FORMAT_UNIT:
 532        case SEARCH_HIGH:
 533        case SEARCH_LOW:
 534        case SEARCH_EQUAL:
 535                return DISCONNECT_LONG;
 536        default:
 537                return DISCONNECT_NONE;
 538        }
 539}
 540
 541static void NCR5380_set_timer(struct NCR5380_hostdata *hostdata, unsigned long timeout)
 542{
 543        hostdata->time_expires = jiffies + timeout;
 544        schedule_delayed_work(&hostdata->coroutine, timeout);
 545}
 546
 547
 548static int probe_irq __initdata = 0;
 549
 550/**
 551 *      probe_intr      -       helper for IRQ autoprobe
 552 *      @irq: interrupt number
 553 *      @dev_id: unused
 554 *      @regs: unused
 555 *
 556 *      Set a flag to indicate the IRQ in question was received. This is
 557 *      used by the IRQ probe code.
 558 */
 559 
 560static irqreturn_t __init probe_intr(int irq, void *dev_id)
 561{
 562        probe_irq = irq;
 563        return IRQ_HANDLED;
 564}
 565
 566/**
 567 *      NCR5380_probe_irq       -       find the IRQ of an NCR5380
 568 *      @instance: NCR5380 controller
 569 *      @possible: bitmask of ISA IRQ lines
 570 *
 571 *      Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ
 572 *      and then looking to see what interrupt actually turned up.
 573 *
 574 *      Locks: none, irqs must be enabled on entry
 575 */
 576
 577static int __init __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance,
 578                                                int possible)
 579{
 580        NCR5380_local_declare();
 581        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
 582        unsigned long timeout;
 583        int trying_irqs, i, mask;
 584        NCR5380_setup(instance);
 585
 586        for (trying_irqs = i = 0, mask = 1; i < 16; ++i, mask <<= 1)
 587                if ((mask & possible) && (request_irq(i, &probe_intr, IRQF_DISABLED, "NCR-probe", NULL) == 0))
 588                        trying_irqs |= mask;
 589
 590        timeout = jiffies + (250 * HZ / 1000);
 591        probe_irq = SCSI_IRQ_NONE;
 592
 593        /*
 594         * A interrupt is triggered whenever BSY = false, SEL = true
 595         * and a bit set in the SELECT_ENABLE_REG is asserted on the 
 596         * SCSI bus.
 597         *
 598         * Note that the bus is only driven when the phase control signals
 599         * (I/O, C/D, and MSG) match those in the TCR, so we must reset that
 600         * to zero.
 601         */
 602
 603        NCR5380_write(TARGET_COMMAND_REG, 0);
 604        NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
 605        NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
 606        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);
 607
 608        while (probe_irq == SCSI_IRQ_NONE && time_before(jiffies, timeout))
 609                schedule_timeout_uninterruptible(1);
 610        
 611        NCR5380_write(SELECT_ENABLE_REG, 0);
 612        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
 613
 614        for (i = 0, mask = 1; i < 16; ++i, mask <<= 1)
 615                if (trying_irqs & mask)
 616                        free_irq(i, NULL);
 617
 618        return probe_irq;
 619}
 620
 621/**
 622 *      NCR58380_print_options  -       show options
 623 *      @instance: unused for now
 624 *
 625 *      Called by probe code indicating the NCR5380 driver options that 
 626 *      were selected. At some point this will switch to runtime options
 627 *      read from the adapter in question
 628 *
 629 *      Locks: none
 630 */
 631
 632static void __init __maybe_unused
 633NCR5380_print_options(struct Scsi_Host *instance)
 634{
 635        printk(" generic options"
 636#ifdef AUTOPROBE_IRQ
 637               " AUTOPROBE_IRQ"
 638#endif
 639#ifdef AUTOSENSE
 640               " AUTOSENSE"
 641#endif
 642#ifdef DIFFERENTIAL
 643               " DIFFERENTIAL"
 644#endif
 645#ifdef REAL_DMA
 646               " REAL DMA"
 647#endif
 648#ifdef REAL_DMA_POLL
 649               " REAL DMA POLL"
 650#endif
 651#ifdef PARITY
 652               " PARITY"
 653#endif
 654#ifdef PSEUDO_DMA
 655               " PSEUDO DMA"
 656#endif
 657#ifdef UNSAFE
 658               " UNSAFE "
 659#endif
 660            );
 661        printk(" USLEEP, USLEEP_POLL=%d USLEEP_SLEEP=%d", USLEEP_POLL, USLEEP_SLEEP);
 662        printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
 663        if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) {
 664                printk(" ncr53c400 release=%d", NCR53C400_PUBLIC_RELEASE);
 665        }
 666}
 667
 668/**
 669 *      NCR5380_print_status    -       dump controller info
 670 *      @instance: controller to dump
 671 *
 672 *      Print commands in the various queues, called from NCR5380_abort 
 673 *      and NCR5380_debug to aid debugging.
 674 *
 675 *      Locks: called functions disable irqs
 676 */
 677
 678static void NCR5380_print_status(struct Scsi_Host *instance)
 679{
 680        NCR5380_dprint(NDEBUG_ANY, instance);
 681        NCR5380_dprint_phase(NDEBUG_ANY, instance);
 682}
 683
 684/******************************************/
 685/*
 686 * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
 687 *
 688 * *buffer: I/O buffer
 689 * **start: if inout == FALSE pointer into buffer where user read should start
 690 * offset: current offset
 691 * length: length of buffer
 692 * hostno: Scsi_Host host_no
 693 * inout: TRUE - user is writing; FALSE - user is reading
 694 *
 695 * Return the number of bytes read from or written
 696 */
 697
 698#undef SPRINTF
 699#define SPRINTF(args...) do { if(pos < buffer + length-80) pos += sprintf(pos, ## args); } while(0)
 700static
 701char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length);
 702static
 703char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len);
 704static
 705char *lprint_opcode(int opcode, char *pos, char *buffer, int length);
 706
 707static int __maybe_unused NCR5380_proc_info(struct Scsi_Host *instance,
 708        char *buffer, char **start, off_t offset, int length, int inout)
 709{
 710        char *pos = buffer;
 711        struct NCR5380_hostdata *hostdata;
 712        Scsi_Cmnd *ptr;
 713
 714        hostdata = (struct NCR5380_hostdata *) instance->hostdata;
 715
 716        if (inout) {            /* Has data been written to the file ? */
 717#ifdef DTC_PUBLIC_RELEASE
 718                dtc_wmaxi = dtc_maxi = 0;
 719#endif
 720#ifdef PAS16_PUBLIC_RELEASE
 721                pas_wmaxi = pas_maxi = 0;
 722#endif
 723                return (-ENOSYS);       /* Currently this is a no-op */
 724        }
 725        SPRINTF("NCR5380 core release=%d.   ", NCR5380_PUBLIC_RELEASE);
 726        if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400)
 727                SPRINTF("ncr53c400 release=%d.  ", NCR53C400_PUBLIC_RELEASE);
 728#ifdef DTC_PUBLIC_RELEASE
 729        SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE);
 730#endif
 731#ifdef T128_PUBLIC_RELEASE
 732        SPRINTF("T128 release %d", T128_PUBLIC_RELEASE);
 733#endif
 734#ifdef GENERIC_NCR5380_PUBLIC_RELEASE
 735        SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE);
 736#endif
 737#ifdef PAS16_PUBLIC_RELEASE
 738        SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE);
 739#endif
 740
 741        SPRINTF("\nBase Addr: 0x%05lX    ", (long) instance->base);
 742        SPRINTF("io_port: %04x      ", (int) instance->io_port);
 743        if (instance->irq == SCSI_IRQ_NONE)
 744                SPRINTF("IRQ: None.\n");
 745        else
 746                SPRINTF("IRQ: %d.\n", instance->irq);
 747
 748#ifdef DTC_PUBLIC_RELEASE
 749        SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", dtc_wmaxi, dtc_maxi);
 750#endif
 751#ifdef PAS16_PUBLIC_RELEASE
 752        SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", pas_wmaxi, pas_maxi);
 753#endif
 754        spin_lock_irq(instance->host_lock);
 755        if (!hostdata->connected)
 756                SPRINTF("scsi%d: no currently connected command\n", instance->host_no);
 757        else
 758                pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, pos, buffer, length);
 759        SPRINTF("scsi%d: issue_queue\n", instance->host_no);
 760        for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
 761                pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
 762
 763        SPRINTF("scsi%d: disconnected_queue\n", instance->host_no);
 764        for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
 765                pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
 766        spin_unlock_irq(instance->host_lock);
 767        
 768        *start = buffer;
 769        if (pos - buffer < offset)
 770                return 0;
 771        else if (pos - buffer - offset < length)
 772                return pos - buffer - offset;
 773        return length;
 774}
 775
 776static char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length)
 777{
 778        SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun);
 779        SPRINTF("        command = ");
 780        pos = lprint_command(cmd->cmnd, pos, buffer, length);
 781        return (pos);
 782}
 783
 784static char *lprint_command(unsigned char *command, char *pos, char *buffer, int length)
 785{
 786        int i, s;
 787        pos = lprint_opcode(command[0], pos, buffer, length);
 788        for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
 789                SPRINTF("%02x ", command[i]);
 790        SPRINTF("\n");
 791        return (pos);
 792}
 793
 794static char *lprint_opcode(int opcode, char *pos, char *buffer, int length)
 795{
 796        SPRINTF("%2d (0x%02x)", opcode, opcode);
 797        return (pos);
 798}
 799
 800
 801/**
 802 *      NCR5380_init    -       initialise an NCR5380
 803 *      @instance: adapter to configure
 804 *      @flags: control flags
 805 *
 806 *      Initializes *instance and corresponding 5380 chip,
 807 *      with flags OR'd into the initial flags value.
 808 *
 809 *      Notes : I assume that the host, hostno, and id bits have been
 810 *      set correctly.  I don't care about the irq and other fields. 
 811 *
 812 *      Returns 0 for success
 813 *
 814 *      Locks: interrupts must be enabled when we are called 
 815 */
 816
 817static int __devinit NCR5380_init(struct Scsi_Host *instance, int flags)
 818{
 819        NCR5380_local_declare();
 820        int i, pass;
 821        unsigned long timeout;
 822        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
 823
 824        if(in_interrupt())
 825                printk(KERN_ERR "NCR5380_init called with interrupts off!\n");
 826        /* 
 827         * On NCR53C400 boards, NCR5380 registers are mapped 8 past 
 828         * the base address.
 829         */
 830
 831#ifdef NCR53C400
 832        if (flags & FLAG_NCR53C400)
 833                instance->NCR5380_instance_name += NCR53C400_address_adjust;
 834#endif
 835
 836        NCR5380_setup(instance);
 837
 838        hostdata->aborted = 0;
 839        hostdata->id_mask = 1 << instance->this_id;
 840        for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
 841                if (i > hostdata->id_mask)
 842                        hostdata->id_higher_mask |= i;
 843        for (i = 0; i < 8; ++i)
 844                hostdata->busy[i] = 0;
 845#ifdef REAL_DMA
 846        hostdata->dmalen = 0;
 847#endif
 848        hostdata->targets_present = 0;
 849        hostdata->connected = NULL;
 850        hostdata->issue_queue = NULL;
 851        hostdata->disconnected_queue = NULL;
 852        
 853        INIT_DELAYED_WORK(&hostdata->coroutine, NCR5380_main);
 854        
 855#ifdef NCR5380_STATS
 856        for (i = 0; i < 8; ++i) {
 857                hostdata->time_read[i] = 0;
 858                hostdata->time_write[i] = 0;
 859                hostdata->bytes_read[i] = 0;
 860                hostdata->bytes_write[i] = 0;
 861        }
 862        hostdata->timebase = 0;
 863        hostdata->pendingw = 0;
 864        hostdata->pendingr = 0;
 865#endif
 866
 867        /* The CHECK code seems to break the 53C400. Will check it later maybe */
 868        if (flags & FLAG_NCR53C400)
 869                hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags;
 870        else
 871                hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags;
 872
 873        hostdata->host = instance;
 874        hostdata->time_expires = 0;
 875
 876#ifndef AUTOSENSE
 877        if ((instance->cmd_per_lun > 1) || instance->can_queue > 1)
 878                    printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" "         without AUTOSENSE option, contingent allegiance conditions may\n"
 879                           "         be incorrectly cleared.\n", instance->host_no);
 880#endif                          /* def AUTOSENSE */
 881
 882        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
 883        NCR5380_write(MODE_REG, MR_BASE);
 884        NCR5380_write(TARGET_COMMAND_REG, 0);
 885        NCR5380_write(SELECT_ENABLE_REG, 0);
 886
 887#ifdef NCR53C400
 888        if (hostdata->flags & FLAG_NCR53C400) {
 889                NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE);
 890        }
 891#endif
 892
 893        /* 
 894         * Detect and correct bus wedge problems.
 895         *
 896         * If the system crashed, it may have crashed in a state 
 897         * where a SCSI command was still executing, and the 
 898         * SCSI bus is not in a BUS FREE STATE.
 899         *
 900         * If this is the case, we'll try to abort the currently
 901         * established nexus which we know nothing about, and that
 902         * failing, do a hard reset of the SCSI bus 
 903         */
 904
 905        for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
 906                switch (pass) {
 907                case 1:
 908                case 3:
 909                case 5:
 910                        printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no);
 911                        timeout = jiffies + 5 * HZ;
 912                        NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ);
 913                        break;
 914                case 2:
 915                        printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no);
 916                        do_abort(instance);
 917                        break;
 918                case 4:
 919                        printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no);
 920                        do_reset(instance);
 921                        break;
 922                case 6:
 923                        printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no);
 924                        return -ENXIO;
 925                }
 926        }
 927        return 0;
 928}
 929
 930/**
 931 *      NCR5380_exit    -       remove an NCR5380
 932 *      @instance: adapter to remove
 933 */
 934
 935static void NCR5380_exit(struct Scsi_Host *instance)
 936{
 937        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
 938
 939        cancel_delayed_work_sync(&hostdata->coroutine);
 940}
 941
 942/**
 943 *      NCR5380_queue_command           -       queue a command
 944 *      @cmd: SCSI command
 945 *      @done: completion handler
 946 *
 947 *      cmd is added to the per instance issue_queue, with minor 
 948 *      twiddling done to the host specific fields of cmd.  If the 
 949 *      main coroutine is not running, it is restarted.
 950 *
 951 *      Locks: host lock taken by caller
 952 */
 953
 954static int NCR5380_queue_command_lck(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *))
 955{
 956        struct Scsi_Host *instance = cmd->device->host;
 957        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
 958        Scsi_Cmnd *tmp;
 959
 960#if (NDEBUG & NDEBUG_NO_WRITE)
 961        switch (cmd->cmnd[0]) {
 962        case WRITE_6:
 963        case WRITE_10:
 964                printk("scsi%d : WRITE attempted with NO_WRITE debugging flag set\n", instance->host_no);
 965                cmd->result = (DID_ERROR << 16);
 966                done(cmd);
 967                return 0;
 968        }
 969#endif                          /* (NDEBUG & NDEBUG_NO_WRITE) */
 970
 971#ifdef NCR5380_STATS
 972        switch (cmd->cmnd[0]) {
 973                case WRITE:
 974                case WRITE_6:
 975                case WRITE_10:
 976                        hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
 977                        hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
 978                        hostdata->pendingw++;
 979                        break;
 980                case READ:
 981                case READ_6:
 982                case READ_10:
 983                        hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
 984                        hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
 985                        hostdata->pendingr++;
 986                        break;
 987        }
 988#endif
 989
 990        /* 
 991         * We use the host_scribble field as a pointer to the next command  
 992         * in a queue 
 993         */
 994
 995        cmd->host_scribble = NULL;
 996        cmd->scsi_done = done;
 997        cmd->result = 0;
 998
 999        /* 
1000         * Insert the cmd into the issue queue. Note that REQUEST SENSE 
1001         * commands are added to the head of the queue since any command will
1002         * clear the contingent allegiance condition that exists and the 
1003         * sense data is only guaranteed to be valid while the condition exists.
1004         */
1005
1006        if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
1007                LIST(cmd, hostdata->issue_queue);
1008                cmd->host_scribble = (unsigned char *) hostdata->issue_queue;
1009                hostdata->issue_queue = cmd;
1010        } else {
1011                for (tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp->host_scribble; tmp = (Scsi_Cmnd *) tmp->host_scribble);
1012                LIST(cmd, tmp);
1013                tmp->host_scribble = (unsigned char *) cmd;
1014        }
1015        dprintk(NDEBUG_QUEUES, ("scsi%d : command added to %s of queue\n", instance->host_no, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"));
1016
1017        /* Run the coroutine if it isn't already running. */
1018        /* Kick off command processing */
1019        schedule_delayed_work(&hostdata->coroutine, 0);
1020        return 0;
1021}
1022
1023static DEF_SCSI_QCMD(NCR5380_queue_command)
1024
1025/**
1026 *      NCR5380_main    -       NCR state machines
1027 *
1028 *      NCR5380_main is a coroutine that runs as long as more work can 
1029 *      be done on the NCR5380 host adapters in a system.  Both 
1030 *      NCR5380_queue_command() and NCR5380_intr() will try to start it 
1031 *      in case it is not running.
1032 * 
1033 *      Locks: called as its own thread with no locks held. Takes the
1034 *      host lock and called routines may take the isa dma lock.
1035 */
1036
1037static void NCR5380_main(struct work_struct *work)
1038{
1039        struct NCR5380_hostdata *hostdata =
1040                container_of(work, struct NCR5380_hostdata, coroutine.work);
1041        struct Scsi_Host *instance = hostdata->host;
1042        Scsi_Cmnd *tmp, *prev;
1043        int done;
1044        
1045        spin_lock_irq(instance->host_lock);
1046        do {
1047                /* Lock held here */
1048                done = 1;
1049                if (!hostdata->connected && !hostdata->selecting) {
1050                        dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no));
1051                        /*
1052                         * Search through the issue_queue for a command destined
1053                         * for a target that's not busy.
1054                         */
1055                        for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 
1056                        {
1057                                if (prev != tmp)
1058                                        dprintk(NDEBUG_LISTS, ("MAIN tmp=%p   target=%d   busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun));
1059                                /*  When we find one, remove it from the issue queue. */
1060                                if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) {
1061                                        if (prev) {
1062                                                REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
1063                                                prev->host_scribble = tmp->host_scribble;
1064                                        } else {
1065                                                REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble);
1066                                                hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble;
1067                                        }
1068                                        tmp->host_scribble = NULL;
1069
1070                                        /* 
1071                                         * Attempt to establish an I_T_L nexus here. 
1072                                         * On success, instance->hostdata->connected is set.
1073                                         * On failure, we must add the command back to the
1074                                         *   issue queue so we can keep trying. 
1075                                         */
1076                                        dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main() : command for target %d lun %d removed from issue_queue\n", instance->host_no, tmp->target, tmp->lun));
1077        
1078                                        /*
1079                                         * A successful selection is defined as one that 
1080                                         * leaves us with the command connected and 
1081                                         * in hostdata->connected, OR has terminated the
1082                                         * command.
1083                                         *
1084                                         * With successful commands, we fall through
1085                                         * and see if we can do an information transfer,
1086                                         * with failures we will restart.
1087                                         */
1088                                        hostdata->selecting = NULL;
1089                                        /* RvC: have to preset this to indicate a new command is being performed */
1090
1091                                        if (!NCR5380_select(instance, tmp,
1092                                                            /* 
1093                                                             * REQUEST SENSE commands are issued without tagged
1094                                                             * queueing, even on SCSI-II devices because the 
1095                                                             * contingent allegiance condition exists for the 
1096                                                             * entire unit.
1097                                                             */
1098                                                            (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1099                                                break;
1100                                        } else {
1101                                                LIST(tmp, hostdata->issue_queue);
1102                                                tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1103                                                hostdata->issue_queue = tmp;
1104                                                done = 0;
1105                                                dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no));
1106                                        }
1107                                        /* lock held here still */
1108                                }       /* if target/lun is not busy */
1109                        }       /* for */
1110                        /* exited locked */
1111                }       /* if (!hostdata->connected) */
1112                if (hostdata->selecting) {
1113                        tmp = (Scsi_Cmnd *) hostdata->selecting;
1114                        /* Selection will drop and retake the lock */
1115                        if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1116                                /* Ok ?? */
1117                        } else {
1118                                /* RvC: device failed, so we wait a long time
1119                                   this is needed for Mustek scanners, that
1120                                   do not respond to commands immediately
1121                                   after a scan */
1122                                printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id);
1123                                LIST(tmp, hostdata->issue_queue);
1124                                tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1125                                hostdata->issue_queue = tmp;
1126                                NCR5380_set_timer(hostdata, USLEEP_WAITLONG);
1127                        }
1128                }       /* if hostdata->selecting */
1129                if (hostdata->connected
1130#ifdef REAL_DMA
1131                    && !hostdata->dmalen
1132#endif
1133                    && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies))
1134                    ) {
1135                        dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no));
1136                        NCR5380_information_transfer(instance);
1137                        dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no));
1138                        done = 0;
1139                } else
1140                        break;
1141        } while (!done);
1142        
1143        spin_unlock_irq(instance->host_lock);
1144}
1145
1146#ifndef DONT_USE_INTR
1147
1148/**
1149 *      NCR5380_intr    -       generic NCR5380 irq handler
1150 *      @irq: interrupt number
1151 *      @dev_id: device info
1152 *
1153 *      Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1154 *      from the disconnected queue, and restarting NCR5380_main() 
1155 *      as required.
1156 *
1157 *      Locks: takes the needed instance locks
1158 */
1159
1160static irqreturn_t NCR5380_intr(int dummy, void *dev_id)
1161{
1162        NCR5380_local_declare();
1163        struct Scsi_Host *instance = dev_id;
1164        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1165        int done;
1166        unsigned char basr;
1167        unsigned long flags;
1168
1169        dprintk(NDEBUG_INTR, ("scsi : NCR5380 irq %d triggered\n",
1170                instance->irq));
1171
1172        do {
1173                done = 1;
1174                spin_lock_irqsave(instance->host_lock, flags);
1175                /* Look for pending interrupts */
1176                NCR5380_setup(instance);
1177                basr = NCR5380_read(BUS_AND_STATUS_REG);
1178                /* XXX dispatch to appropriate routine if found and done=0 */
1179                if (basr & BASR_IRQ) {
1180                        NCR5380_dprint(NDEBUG_INTR, instance);
1181                        if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1182                                done = 0;
1183                                dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no));
1184                                NCR5380_reselect(instance);
1185                                (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1186                        } else if (basr & BASR_PARITY_ERROR) {
1187                                dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no));
1188                                (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1189                        } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1190                                dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no));
1191                                (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1192                        } else {
1193#if defined(REAL_DMA)
1194                                /*
1195                                 * We should only get PHASE MISMATCH and EOP interrupts
1196                                 * if we have DMA enabled, so do a sanity check based on
1197                                 * the current setting of the MODE register.
1198                                 */
1199
1200                                if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) {
1201                                        int transferred;
1202
1203                                        if (!hostdata->connected)
1204                                                panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno);
1205
1206                                        transferred = (hostdata->dmalen - NCR5380_dma_residual(instance));
1207                                        hostdata->connected->SCp.this_residual -= transferred;
1208                                        hostdata->connected->SCp.ptr += transferred;
1209                                        hostdata->dmalen = 0;
1210
1211                                        (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1212                                                        
1213                                        /* FIXME: we need to poll briefly then defer a workqueue task ! */
1214                                        NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ);
1215
1216                                        NCR5380_write(MODE_REG, MR_BASE);
1217                                        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1218                                }
1219#else
1220                                dprintk(NDEBUG_INTR, ("scsi : unknown interrupt, BASR 0x%X, MR 0x%X, SR 0x%x\n", basr, NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)));
1221                                (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1222#endif
1223                        }
1224                }       /* if BASR_IRQ */
1225                spin_unlock_irqrestore(instance->host_lock, flags);
1226                if(!done)
1227                        schedule_delayed_work(&hostdata->coroutine, 0);
1228        } while (!done);
1229        return IRQ_HANDLED;
1230}
1231
1232#endif 
1233
1234/**
1235 *      collect_stats           -       collect stats on a scsi command
1236 *      @hostdata: adapter 
1237 *      @cmd: command being issued
1238 *
1239 *      Update the statistical data by parsing the command in question
1240 */
1241 
1242static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd) 
1243{
1244#ifdef NCR5380_STATS
1245        switch (cmd->cmnd[0]) {
1246        case WRITE:
1247        case WRITE_6:
1248        case WRITE_10:
1249                hostdata->time_write[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1250                hostdata->pendingw--;
1251                break;
1252        case READ:
1253        case READ_6:
1254        case READ_10:
1255                hostdata->time_read[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1256                hostdata->pendingr--;
1257                break;
1258        }
1259#endif
1260}
1261
1262
1263/* 
1264 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, 
1265 *      int tag);
1266 *
1267 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1268 *      including ARBITRATION, SELECTION, and initial message out for 
1269 *      IDENTIFY and queue messages. 
1270 *
1271 * Inputs : instance - instantiation of the 5380 driver on which this 
1272 *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 
1273 *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 
1274 *      the command that is presently connected.
1275 * 
1276 * Returns : -1 if selection could not execute for some reason,
1277 *      0 if selection succeeded or failed because the target 
1278 *      did not respond.
1279 *
1280 * Side effects : 
1281 *      If bus busy, arbitration failed, etc, NCR5380_select() will exit 
1282 *              with registers as they should have been on entry - ie
1283 *              SELECT_ENABLE will be set appropriately, the NCR5380
1284 *              will cease to drive any SCSI bus signals.
1285 *
1286 *      If successful : I_T_L or I_T_L_Q nexus will be established, 
1287 *              instance->connected will be set to cmd.  
1288 *              SELECT interrupt will be disabled.
1289 *
1290 *      If failed (no target) : cmd->scsi_done() will be called, and the 
1291 *              cmd->result host byte set to DID_BAD_TARGET.
1292 *
1293 *      Locks: caller holds hostdata lock in IRQ mode
1294 */
1295 
1296static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag) 
1297{
1298        NCR5380_local_declare();
1299        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1300        unsigned char tmp[3], phase;
1301        unsigned char *data;
1302        int len;
1303        unsigned long timeout;
1304        unsigned char value;
1305        int err;
1306        NCR5380_setup(instance);
1307
1308        if (hostdata->selecting)
1309                goto part2;
1310
1311        hostdata->restart_select = 0;
1312
1313        NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1314        dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id));
1315
1316        /* 
1317         * Set the phase bits to 0, otherwise the NCR5380 won't drive the 
1318         * data bus during SELECTION.
1319         */
1320
1321        NCR5380_write(TARGET_COMMAND_REG, 0);
1322
1323        /* 
1324         * Start arbitration.
1325         */
1326
1327        NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1328        NCR5380_write(MODE_REG, MR_ARBITRATE);
1329
1330
1331        /* We can be relaxed here, interrupts are on, we are
1332           in workqueue context, the birds are singing in the trees */
1333        spin_unlock_irq(instance->host_lock);
1334        err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ);
1335        spin_lock_irq(instance->host_lock);
1336        if (err < 0) {
1337                printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);
1338                NCR5380_write(MODE_REG, MR_BASE);
1339                NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1340                goto failed;
1341        }
1342
1343        dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no));
1344
1345        /* 
1346         * The arbitration delay is 2.2us, but this is a minimum and there is 
1347         * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1348         * the integral nature of udelay().
1349         *
1350         */
1351
1352        udelay(3);
1353
1354        /* Check for lost arbitration */
1355        if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1356                NCR5380_write(MODE_REG, MR_BASE);
1357                dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no));
1358                goto failed;
1359        }
1360        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL);
1361
1362        if (!(hostdata->flags & FLAG_DTC3181E) &&
1363            /* RvC: DTC3181E has some trouble with this
1364             *      so we simply removed it. Seems to work with
1365             *      only Mustek scanner attached
1366             */
1367            (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1368                NCR5380_write(MODE_REG, MR_BASE);
1369                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1370                dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no));
1371                goto failed;
1372        }
1373        /* 
1374         * Again, bus clear + bus settle time is 1.2us, however, this is 
1375         * a minimum so we'll udelay ceil(1.2)
1376         */
1377
1378        udelay(2);
1379
1380        dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no));
1381
1382        /* 
1383         * Now that we have won arbitration, start Selection process, asserting 
1384         * the host and target ID's on the SCSI bus.
1385         */
1386
1387        NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << scmd_id(cmd))));
1388
1389        /* 
1390         * Raise ATN while SEL is true before BSY goes false from arbitration,
1391         * since this is the only way to guarantee that we'll get a MESSAGE OUT
1392         * phase immediately after selection.
1393         */
1394
1395        NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1396        NCR5380_write(MODE_REG, MR_BASE);
1397
1398        /* 
1399         * Reselect interrupts must be turned off prior to the dropping of BSY,
1400         * otherwise we will trigger an interrupt.
1401         */
1402        NCR5380_write(SELECT_ENABLE_REG, 0);
1403
1404        /*
1405         * The initiator shall then wait at least two deskew delays and release 
1406         * the BSY signal.
1407         */
1408        udelay(1);              /* wingel -- wait two bus deskew delay >2*45ns */
1409
1410        /* Reset BSY */
1411        NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1412
1413        /* 
1414         * Something weird happens when we cease to drive BSY - looks
1415         * like the board/chip is letting us do another read before the 
1416         * appropriate propagation delay has expired, and we're confusing
1417         * a BSY signal from ourselves as the target's response to SELECTION.
1418         *
1419         * A small delay (the 'C++' frontend breaks the pipeline with an
1420         * unnecessary jump, making it work on my 386-33/Trantor T128, the
1421         * tighter 'C' code breaks and requires this) solves the problem - 
1422         * the 1 us delay is arbitrary, and only used because this delay will 
1423         * be the same on other platforms and since it works here, it should 
1424         * work there.
1425         *
1426         * wingel suggests that this could be due to failing to wait
1427         * one deskew delay.
1428         */
1429
1430        udelay(1);
1431
1432        dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, scmd_id(cmd)));
1433
1434        /* 
1435         * The SCSI specification calls for a 250 ms timeout for the actual 
1436         * selection.
1437         */
1438
1439        timeout = jiffies + (250 * HZ / 1000);
1440
1441        /* 
1442         * XXX very interesting - we're seeing a bounce where the BSY we 
1443         * asserted is being reflected / still asserted (propagation delay?)
1444         * and it's detecting as true.  Sigh.
1445         */
1446
1447        hostdata->select_time = 0;      /* we count the clock ticks at which we polled */
1448        hostdata->selecting = cmd;
1449
1450part2:
1451        /* RvC: here we enter after a sleeping period, or immediately after
1452           execution of part 1
1453           we poll only once ech clock tick */
1454        value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO);
1455
1456        if (!value && (hostdata->select_time < HZ/4)) {
1457                /* RvC: we still must wait for a device response */
1458                hostdata->select_time++;        /* after 25 ticks the device has failed */
1459                NCR5380_set_timer(hostdata, 1);
1460                return 0;       /* RvC: we return here with hostdata->selecting set,
1461                                   to go to sleep */
1462        }
1463
1464        hostdata->selecting = NULL;/* clear this pointer, because we passed the
1465                                           waiting period */
1466        if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1467                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1468                NCR5380_reselect(instance);
1469                printk("scsi%d : reselection after won arbitration?\n", instance->host_no);
1470                NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1471                return -1;
1472        }
1473        /* 
1474         * No less than two deskew delays after the initiator detects the 
1475         * BSY signal is true, it shall release the SEL signal and may 
1476         * change the DATA BUS.                                     -wingel
1477         */
1478
1479        udelay(1);
1480
1481        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1482
1483        if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1484                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1485                if (hostdata->targets_present & (1 << scmd_id(cmd))) {
1486                        printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no);
1487                        if (hostdata->restart_select)
1488                                printk(KERN_DEBUG "\trestart select\n");
1489                        NCR5380_dprint(NDEBUG_SELECTION, instance);
1490                        NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1491                        return -1;
1492                }
1493                cmd->result = DID_BAD_TARGET << 16;
1494                collect_stats(hostdata, cmd);
1495                cmd->scsi_done(cmd);
1496                NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1497                dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no));
1498                NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1499                return 0;
1500        }
1501        hostdata->targets_present |= (1 << scmd_id(cmd));
1502
1503        /*
1504         * Since we followed the SCSI spec, and raised ATN while SEL 
1505         * was true but before BSY was false during selection, the information
1506         * transfer phase should be a MESSAGE OUT phase so that we can send the
1507         * IDENTIFY message.
1508         * 
1509         * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1510         * message (2 bytes) with a tag ID that we increment with every command
1511         * until it wraps back to 0.
1512         *
1513         * XXX - it turns out that there are some broken SCSI-II devices,
1514         *       which claim to support tagged queuing but fail when more than
1515         *       some number of commands are issued at once.
1516         */
1517
1518        /* Wait for start of REQ/ACK handshake */
1519
1520        spin_unlock_irq(instance->host_lock);
1521        err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
1522        spin_lock_irq(instance->host_lock);
1523        
1524        if(err) {
1525                printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);
1526                NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1527                goto failed;
1528        }
1529
1530        dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id));
1531        tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun);
1532
1533        len = 1;
1534        cmd->tag = 0;
1535
1536        /* Send message(s) */
1537        data = tmp;
1538        phase = PHASE_MSGOUT;
1539        NCR5380_transfer_pio(instance, &phase, &len, &data);
1540        dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no));
1541        /* XXX need to handle errors here */
1542        hostdata->connected = cmd;
1543        hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1544
1545        initialize_SCp(cmd);
1546
1547        return 0;
1548
1549        /* Selection failed */
1550failed:
1551        return -1;
1552
1553}
1554
1555/* 
1556 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 
1557 *      unsigned char *phase, int *count, unsigned char **data)
1558 *
1559 * Purpose : transfers data in given phase using polled I/O
1560 *
1561 * Inputs : instance - instance of driver, *phase - pointer to 
1562 *      what phase is expected, *count - pointer to number of 
1563 *      bytes to transfer, **data - pointer to data pointer.
1564 * 
1565 * Returns : -1 when different phase is entered without transferring
1566 *      maximum number of bytes, 0 if all bytes or transferred or exit
1567 *      is in same phase.
1568 *
1569 *      Also, *phase, *count, *data are modified in place.
1570 *
1571 * XXX Note : handling for bus free may be useful.
1572 */
1573
1574/*
1575 * Note : this code is not as quick as it could be, however it 
1576 * IS 100% reliable, and for the actual data transfer where speed
1577 * counts, we will always do a pseudo DMA or DMA transfer.
1578 */
1579
1580static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1581        NCR5380_local_declare();
1582        unsigned char p = *phase, tmp;
1583        int c = *count;
1584        unsigned char *d = *data;
1585        /*
1586         *      RvC: some administrative data to process polling time
1587         */
1588        int break_allowed = 0;
1589        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1590        NCR5380_setup(instance);
1591
1592        if (!(p & SR_IO))
1593                dprintk(NDEBUG_PIO, ("scsi%d : pio write %d bytes\n", instance->host_no, c));
1594        else
1595                dprintk(NDEBUG_PIO, ("scsi%d : pio read %d bytes\n", instance->host_no, c));
1596
1597        /* 
1598         * The NCR5380 chip will only drive the SCSI bus when the 
1599         * phase specified in the appropriate bits of the TARGET COMMAND
1600         * REGISTER match the STATUS REGISTER
1601         */
1602
1603         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1604
1605        /* RvC: don't know if this is necessary, but other SCSI I/O is short
1606         *      so breaks are not necessary there
1607         */
1608        if ((p == PHASE_DATAIN) || (p == PHASE_DATAOUT)) {
1609                break_allowed = 1;
1610        }
1611        do {
1612                /* 
1613                 * Wait for assertion of REQ, after which the phase bits will be 
1614                 * valid 
1615                 */
1616
1617                /* RvC: we simply poll once, after that we stop temporarily
1618                 *      and let the device buffer fill up
1619                 *      if breaking is not allowed, we keep polling as long as needed
1620                 */
1621
1622                /* FIXME */
1623                while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ) && !break_allowed);
1624                if (!(tmp & SR_REQ)) {
1625                        /* timeout condition */
1626                        NCR5380_set_timer(hostdata, USLEEP_SLEEP);
1627                        break;
1628                }
1629
1630                dprintk(NDEBUG_HANDSHAKE, ("scsi%d : REQ detected\n", instance->host_no));
1631
1632                /* Check for phase mismatch */
1633                if ((tmp & PHASE_MASK) != p) {
1634                        dprintk(NDEBUG_HANDSHAKE, ("scsi%d : phase mismatch\n", instance->host_no));
1635                        NCR5380_dprint_phase(NDEBUG_HANDSHAKE, instance);
1636                        break;
1637                }
1638                /* Do actual transfer from SCSI bus to / from memory */
1639                if (!(p & SR_IO))
1640                        NCR5380_write(OUTPUT_DATA_REG, *d);
1641                else
1642                        *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1643
1644                ++d;
1645
1646                /* 
1647                 * The SCSI standard suggests that in MSGOUT phase, the initiator
1648                 * should drop ATN on the last byte of the message phase
1649                 * after REQ has been asserted for the handshake but before
1650                 * the initiator raises ACK.
1651                 */
1652
1653                if (!(p & SR_IO)) {
1654                        if (!((p & SR_MSG) && c > 1)) {
1655                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1656                                NCR5380_dprint(NDEBUG_PIO, instance);
1657                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1658                        } else {
1659                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1660                                NCR5380_dprint(NDEBUG_PIO, instance);
1661                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1662                        }
1663                } else {
1664                        NCR5380_dprint(NDEBUG_PIO, instance);
1665                        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1666                }
1667
1668                /* FIXME - if this fails bus reset ?? */
1669                NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 5*HZ);
1670                dprintk(NDEBUG_HANDSHAKE, ("scsi%d : req false, handshake complete\n", instance->host_no));
1671
1672/*
1673 * We have several special cases to consider during REQ/ACK handshaking : 
1674 * 1.  We were in MSGOUT phase, and we are on the last byte of the 
1675 *      message.  ATN must be dropped as ACK is dropped.
1676 *
1677 * 2.  We are in a MSGIN phase, and we are on the last byte of the  
1678 *      message.  We must exit with ACK asserted, so that the calling
1679 *      code may raise ATN before dropping ACK to reject the message.
1680 *
1681 * 3.  ACK and ATN are clear and the target may proceed as normal.
1682 */
1683                if (!(p == PHASE_MSGIN && c == 1)) {
1684                        if (p == PHASE_MSGOUT && c > 1)
1685                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1686                        else
1687                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1688                }
1689        } while (--c);
1690
1691        dprintk(NDEBUG_PIO, ("scsi%d : residual %d\n", instance->host_no, c));
1692
1693        *count = c;
1694        *data = d;
1695        tmp = NCR5380_read(STATUS_REG);
1696        if (tmp & SR_REQ)
1697                *phase = tmp & PHASE_MASK;
1698        else
1699                *phase = PHASE_UNKNOWN;
1700
1701        if (!c || (*phase == p))
1702                return 0;
1703        else
1704                return -1;
1705}
1706
1707/**
1708 *      do_reset        -       issue a reset command
1709 *      @host: adapter to reset
1710 *
1711 *      Issue a reset sequence to the NCR5380 and try and get the bus
1712 *      back into sane shape.
1713 *
1714 *      Locks: caller holds queue lock
1715 */
1716 
1717static void do_reset(struct Scsi_Host *host) {
1718        NCR5380_local_declare();
1719        NCR5380_setup(host);
1720
1721        NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
1722        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1723        udelay(25);
1724        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1725}
1726
1727/*
1728 * Function : do_abort (Scsi_Host *host)
1729 * 
1730 * Purpose : abort the currently established nexus.  Should only be 
1731 *      called from a routine which can drop into a 
1732 * 
1733 * Returns : 0 on success, -1 on failure.
1734 *
1735 * Locks: queue lock held by caller
1736 *      FIXME: sort this out and get new_eh running
1737 */
1738
1739static int do_abort(struct Scsi_Host *host) {
1740        NCR5380_local_declare();
1741        unsigned char *msgptr, phase, tmp;
1742        int len;
1743        int rc;
1744        NCR5380_setup(host);
1745
1746
1747        /* Request message out phase */
1748        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1749
1750        /* 
1751         * Wait for the target to indicate a valid phase by asserting 
1752         * REQ.  Once this happens, we'll have either a MSGOUT phase 
1753         * and can immediately send the ABORT message, or we'll have some 
1754         * other phase and will have to source/sink data.
1755         * 
1756         * We really don't care what value was on the bus or what value
1757         * the target sees, so we just handshake.
1758         */
1759
1760        rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, SR_REQ, 60 * HZ);
1761        
1762        if(rc < 0)
1763                return -1;
1764
1765        tmp = (unsigned char)rc;
1766        
1767        NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1768
1769        if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1770                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1771                rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, 0, 3*HZ);
1772                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1773                if(rc == -1)
1774                        return -1;
1775        }
1776        tmp = ABORT;
1777        msgptr = &tmp;
1778        len = 1;
1779        phase = PHASE_MSGOUT;
1780        NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1781
1782        /*
1783         * If we got here, and the command completed successfully,
1784         * we're about to go into bus free state.
1785         */
1786
1787        return len ? -1 : 0;
1788}
1789
1790#if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL)
1791/* 
1792 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 
1793 *      unsigned char *phase, int *count, unsigned char **data)
1794 *
1795 * Purpose : transfers data in given phase using either real
1796 *      or pseudo DMA.
1797 *
1798 * Inputs : instance - instance of driver, *phase - pointer to 
1799 *      what phase is expected, *count - pointer to number of 
1800 *      bytes to transfer, **data - pointer to data pointer.
1801 * 
1802 * Returns : -1 when different phase is entered without transferring
1803 *      maximum number of bytes, 0 if all bytes or transferred or exit
1804 *      is in same phase.
1805 *
1806 *      Also, *phase, *count, *data are modified in place.
1807 *
1808 *      Locks: io_request lock held by caller
1809 */
1810
1811
1812static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1813        NCR5380_local_declare();
1814        register int c = *count;
1815        register unsigned char p = *phase;
1816        register unsigned char *d = *data;
1817        unsigned char tmp;
1818        int foo;
1819#if defined(REAL_DMA_POLL)
1820        int cnt, toPIO;
1821        unsigned char saved_data = 0, overrun = 0, residue;
1822#endif
1823
1824        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1825
1826        NCR5380_setup(instance);
1827
1828        if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1829                *phase = tmp;
1830                return -1;
1831        }
1832#if defined(REAL_DMA) || defined(REAL_DMA_POLL)
1833#ifdef READ_OVERRUNS
1834        if (p & SR_IO) {
1835                c -= 2;
1836        }
1837#endif
1838        dprintk(NDEBUG_DMA, ("scsi%d : initializing DMA channel %d for %s, %d bytes %s %0x\n", instance->host_no, instance->dma_channel, (p & SR_IO) ? "reading" : "writing", c, (p & SR_IO) ? "to" : "from", (unsigned) d));
1839        hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c);
1840#endif
1841
1842        NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1843
1844#ifdef REAL_DMA
1845        NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1846#elif defined(REAL_DMA_POLL)
1847        NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1848#else
1849        /*
1850         * Note : on my sample board, watch-dog timeouts occurred when interrupts
1851         * were not disabled for the duration of a single DMA transfer, from 
1852         * before the setting of DMA mode to after transfer of the last byte.
1853         */
1854
1855#if defined(PSEUDO_DMA) && defined(UNSAFE)
1856        spin_unlock_irq(instance->host_lock);
1857#endif
1858        /* KLL May need eop and parity in 53c400 */
1859        if (hostdata->flags & FLAG_NCR53C400)
1860                NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE |
1861                                MR_ENABLE_PAR_CHECK | MR_ENABLE_PAR_INTR |
1862                                MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1863        else
1864                NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1865#endif                          /* def REAL_DMA */
1866
1867        dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG)));
1868
1869        /* 
1870         *      On the PAS16 at least I/O recovery delays are not needed here.
1871         *      Everyone else seems to want them.
1872         */
1873
1874        if (p & SR_IO) {
1875                io_recovery_delay(1);
1876                NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1877        } else {
1878                io_recovery_delay(1);
1879                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1880                io_recovery_delay(1);
1881                NCR5380_write(START_DMA_SEND_REG, 0);
1882                io_recovery_delay(1);
1883        }
1884
1885#if defined(REAL_DMA_POLL)
1886        do {
1887                tmp = NCR5380_read(BUS_AND_STATUS_REG);
1888        } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER)));
1889
1890/*
1891   At this point, either we've completed DMA, or we have a phase mismatch,
1892   or we've unexpectedly lost BUSY (which is a real error).
1893
1894   For write DMAs, we want to wait until the last byte has been
1895   transferred out over the bus before we turn off DMA mode.  Alas, there
1896   seems to be no terribly good way of doing this on a 5380 under all
1897   conditions.  For non-scatter-gather operations, we can wait until REQ
1898   and ACK both go false, or until a phase mismatch occurs.  Gather-writes
1899   are nastier, since the device will be expecting more data than we
1900   are prepared to send it, and REQ will remain asserted.  On a 53C8[01] we
1901   could test LAST BIT SENT to assure transfer (I imagine this is precisely
1902   why this signal was added to the newer chips) but on the older 538[01]
1903   this signal does not exist.  The workaround for this lack is a watchdog;
1904   we bail out of the wait-loop after a modest amount of wait-time if
1905   the usual exit conditions are not met.  Not a terribly clean or
1906   correct solution :-%
1907
1908   Reads are equally tricky due to a nasty characteristic of the NCR5380.
1909   If the chip is in DMA mode for an READ, it will respond to a target's
1910   REQ by latching the SCSI data into the INPUT DATA register and asserting
1911   ACK, even if it has _already_ been notified by the DMA controller that
1912   the current DMA transfer has completed!  If the NCR5380 is then taken
1913   out of DMA mode, this already-acknowledged byte is lost.
1914
1915   This is not a problem for "one DMA transfer per command" reads, because
1916   the situation will never arise... either all of the data is DMA'ed
1917   properly, or the target switches to MESSAGE IN phase to signal a
1918   disconnection (either operation bringing the DMA to a clean halt).
1919   However, in order to handle scatter-reads, we must work around the
1920   problem.  The chosen fix is to DMA N-2 bytes, then check for the
1921   condition before taking the NCR5380 out of DMA mode.  One or two extra
1922   bytes are transferred via PIO as necessary to fill out the original
1923   request.
1924 */
1925
1926        if (p & SR_IO) {
1927#ifdef READ_OVERRUNS
1928                udelay(10);
1929                if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) {
1930                        saved_data = NCR5380_read(INPUT_DATA_REGISTER);
1931                        overrun = 1;
1932                }
1933#endif
1934        } else {
1935                int limit = 100;
1936                while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) {
1937                        if (!(tmp & BASR_PHASE_MATCH))
1938                                break;
1939                        if (--limit < 0)
1940                                break;
1941                }
1942        }
1943
1944        dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG)));
1945
1946        NCR5380_write(MODE_REG, MR_BASE);
1947        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1948
1949        residue = NCR5380_dma_residual(instance);
1950        c -= residue;
1951        *count -= c;
1952        *data += c;
1953        *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
1954
1955#ifdef READ_OVERRUNS
1956        if (*phase == p && (p & SR_IO) && residue == 0) {
1957                if (overrun) {
1958                        dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n"));
1959                        **data = saved_data;
1960                        *data += 1;
1961                        *count -= 1;
1962                        cnt = toPIO = 1;
1963                } else {
1964                        printk("No overrun??\n");
1965                        cnt = toPIO = 2;
1966                }
1967                dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data));
1968                NCR5380_transfer_pio(instance, phase, &cnt, data);
1969                *count -= toPIO - cnt;
1970        }
1971#endif
1972
1973        dprintk(NDEBUG_DMA, ("Return with data ptr = 0x%X, count %d, last 0x%X, next 0x%X\n", *data, *count, *(*data + *count - 1), *(*data + *count)));
1974        return 0;
1975
1976#elif defined(REAL_DMA)
1977        return 0;
1978#else                           /* defined(REAL_DMA_POLL) */
1979        if (p & SR_IO) {
1980#ifdef DMA_WORKS_RIGHT
1981                foo = NCR5380_pread(instance, d, c);
1982#else
1983                int diff = 1;
1984                if (hostdata->flags & FLAG_NCR53C400) {
1985                        diff = 0;
1986                }
1987                if (!(foo = NCR5380_pread(instance, d, c - diff))) {
1988                        /*
1989                         * We can't disable DMA mode after successfully transferring 
1990                         * what we plan to be the last byte, since that would open up
1991                         * a race condition where if the target asserted REQ before 
1992                         * we got the DMA mode reset, the NCR5380 would have latched
1993                         * an additional byte into the INPUT DATA register and we'd
1994                         * have dropped it.
1995                         * 
1996                         * The workaround was to transfer one fewer bytes than we 
1997                         * intended to with the pseudo-DMA read function, wait for 
1998                         * the chip to latch the last byte, read it, and then disable
1999                         * pseudo-DMA mode.
2000                         * 
2001                         * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
2002                         * REQ is deasserted when ACK is asserted, and not reasserted
2003                         * until ACK goes false.  Since the NCR5380 won't lower ACK
2004                         * until DACK is asserted, which won't happen unless we twiddle
2005                         * the DMA port or we take the NCR5380 out of DMA mode, we 
2006                         * can guarantee that we won't handshake another extra 
2007                         * byte.
2008                         */
2009
2010                        if (!(hostdata->flags & FLAG_NCR53C400)) {
2011                                while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
2012                                /* Wait for clean handshake */
2013                                while (NCR5380_read(STATUS_REG) & SR_REQ);
2014                                d[c - 1] = NCR5380_read(INPUT_DATA_REG);
2015                        }
2016                }
2017#endif
2018        } else {
2019#ifdef DMA_WORKS_RIGHT
2020                foo = NCR5380_pwrite(instance, d, c);
2021#else
2022                int timeout;
2023                dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c));
2024                if (!(foo = NCR5380_pwrite(instance, d, c))) {
2025                        /*
2026                         * Wait for the last byte to be sent.  If REQ is being asserted for 
2027                         * the byte we're interested, we'll ACK it and it will go false.  
2028                         */
2029                        if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
2030                                timeout = 20000;
2031                                while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));
2032
2033                                if (!timeout)
2034                                        dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no));
2035
2036                                if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
2037                                        hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
2038                                        if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
2039                                                hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
2040                                                dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no));
2041                                        }
2042                                }
2043                        } else {
2044                                dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n"));
2045                                while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
2046                                dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n"));
2047                        }
2048                }
2049#endif
2050        }
2051        NCR5380_write(MODE_REG, MR_BASE);
2052        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2053
2054        if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) {
2055                dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n"));
2056                if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) {
2057                        dprintk(NDEBUG_C400_PWRITE, ("53C400w:    got it, reading reset interrupt reg\n"));
2058                        NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2059                } else {
2060                        printk("53C400w:    IRQ NOT THERE!\n");
2061                }
2062        }
2063        *data = d + c;
2064        *count = 0;
2065        *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
2066#if defined(PSEUDO_DMA) && defined(UNSAFE)
2067        spin_lock_irq(instance->host_lock);
2068#endif                          /* defined(REAL_DMA_POLL) */
2069        return foo;
2070#endif                          /* def REAL_DMA */
2071}
2072#endif                          /* defined(REAL_DMA) | defined(PSEUDO_DMA) */
2073
2074/*
2075 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
2076 *
2077 * Purpose : run through the various SCSI phases and do as the target 
2078 *      directs us to.  Operates on the currently connected command, 
2079 *      instance->connected.
2080 *
2081 * Inputs : instance, instance for which we are doing commands
2082 *
2083 * Side effects : SCSI things happen, the disconnected queue will be 
2084 *      modified if a command disconnects, *instance->connected will
2085 *      change.
2086 *
2087 * XXX Note : we need to watch for bus free or a reset condition here 
2088 *      to recover from an unexpected bus free condition.
2089 *
2090 * Locks: io_request_lock held by caller in IRQ mode
2091 */
2092
2093static void NCR5380_information_transfer(struct Scsi_Host *instance) {
2094        NCR5380_local_declare();
2095        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata;
2096        unsigned char msgout = NOP;
2097        int sink = 0;
2098        int len;
2099#if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2100        int transfersize;
2101#endif
2102        unsigned char *data;
2103        unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2104        Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2105        /* RvC: we need to set the end of the polling time */
2106        unsigned long poll_time = jiffies + USLEEP_POLL;
2107
2108        NCR5380_setup(instance);
2109
2110        while (1) {
2111                tmp = NCR5380_read(STATUS_REG);
2112                /* We only have a valid SCSI phase when REQ is asserted */
2113                if (tmp & SR_REQ) {
2114                        phase = (tmp & PHASE_MASK);
2115                        if (phase != old_phase) {
2116                                old_phase = phase;
2117                                NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
2118                        }
2119                        if (sink && (phase != PHASE_MSGOUT)) {
2120                                NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2121
2122                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
2123                                while (NCR5380_read(STATUS_REG) & SR_REQ);
2124                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2125                                sink = 0;
2126                                continue;
2127                        }
2128                        switch (phase) {
2129                        case PHASE_DATAIN:
2130                        case PHASE_DATAOUT:
2131#if (NDEBUG & NDEBUG_NO_DATAOUT)
2132                                printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no);
2133                                sink = 1;
2134                                do_abort(instance);
2135                                cmd->result = DID_ERROR << 16;
2136                                cmd->scsi_done(cmd);
2137                                return;
2138#endif
2139                                /* 
2140                                 * If there is no room left in the current buffer in the
2141                                 * scatter-gather list, move onto the next one.
2142                                 */
2143
2144                                if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2145                                        ++cmd->SCp.buffer;
2146                                        --cmd->SCp.buffers_residual;
2147                                        cmd->SCp.this_residual = cmd->SCp.buffer->length;
2148                                        cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2149                                        dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual));
2150                                }
2151                                /*
2152                                 * The preferred transfer method is going to be 
2153                                 * PSEUDO-DMA for systems that are strictly PIO,
2154                                 * since we can let the hardware do the handshaking.
2155                                 *
2156                                 * For this to work, we need to know the transfersize
2157                                 * ahead of time, since the pseudo-DMA code will sit
2158                                 * in an unconditional loop.
2159                                 */
2160
2161#if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2162                                /* KLL
2163                                 * PSEUDO_DMA is defined here. If this is the g_NCR5380
2164                                 * driver then it will always be defined, so the
2165                                 * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base
2166                                 * NCR5380 case.  I think this is a fairly clean solution.
2167                                 * We supplement these 2 if's with the flag.
2168                                 */
2169#ifdef NCR5380_dma_xfer_len
2170                                if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) {
2171#else
2172                                transfersize = cmd->transfersize;
2173
2174#ifdef LIMIT_TRANSFERSIZE       /* If we have problems with interrupt service */
2175                                if (transfersize > 512)
2176                                        transfersize = 512;
2177#endif                          /* LIMIT_TRANSFERSIZE */
2178
2179                                if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) {
2180                                        /* Limit transfers to 32K, for xx400 & xx406
2181                                         * pseudoDMA that transfers in 128 bytes blocks. */
2182                                        if (transfersize > 32 * 1024)
2183                                                transfersize = 32 * 1024;
2184#endif
2185                                        len = transfersize;
2186                                        if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) {
2187                                                /*
2188                                                 * If the watchdog timer fires, all future accesses to this
2189                                                 * device will use the polled-IO.
2190                                                 */
2191                                                scmd_printk(KERN_INFO, cmd,
2192                                                            "switching to slow handshake\n");
2193                                                cmd->device->borken = 1;
2194                                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2195                                                sink = 1;
2196                                                do_abort(instance);
2197                                                cmd->result = DID_ERROR << 16;
2198                                                cmd->scsi_done(cmd);
2199                                                /* XXX - need to source or sink data here, as appropriate */
2200                                        } else
2201                                                cmd->SCp.this_residual -= transfersize - len;
2202                                } else
2203#endif                          /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
2204                                        NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **)
2205                                                             &cmd->SCp.ptr);
2206                                break;
2207                        case PHASE_MSGIN:
2208                                len = 1;
2209                                data = &tmp;
2210                                NCR5380_transfer_pio(instance, &phase, &len, &data);
2211                                cmd->SCp.Message = tmp;
2212
2213                                switch (tmp) {
2214                                        /*
2215                                         * Linking lets us reduce the time required to get the 
2216                                         * next command out to the device, hopefully this will
2217                                         * mean we don't waste another revolution due to the delays
2218                                         * required by ARBITRATION and another SELECTION.
2219                                         *
2220                                         * In the current implementation proposal, low level drivers
2221                                         * merely have to start the next command, pointed to by 
2222                                         * next_link, done() is called as with unlinked commands.
2223                                         */
2224#ifdef LINKED
2225                                case LINKED_CMD_COMPLETE:
2226                                case LINKED_FLG_CMD_COMPLETE:
2227                                        /* Accept message by clearing ACK */
2228                                        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2229                                        dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun));
2230                                        /* 
2231                                         * Sanity check : A linked command should only terminate with
2232                                         * one of these messages if there are more linked commands
2233                                         * available.
2234                                         */
2235                                        if (!cmd->next_link) {
2236                                                printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun);
2237                                                sink = 1;
2238                                                do_abort(instance);
2239                                                return;
2240                                        }
2241                                        initialize_SCp(cmd->next_link);
2242                                        /* The next command is still part of this process */
2243                                        cmd->next_link->tag = cmd->tag;
2244                                        cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2245                                        dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked request done, calling scsi_done().\n", instance->host_no, cmd->device->id, cmd->device->lun));
2246                                        collect_stats(hostdata, cmd);
2247                                        cmd->scsi_done(cmd);
2248                                        cmd = hostdata->connected;
2249                                        break;
2250#endif                          /* def LINKED */
2251                                case ABORT:
2252                                case COMMAND_COMPLETE:
2253                                        /* Accept message by clearing ACK */
2254                                        sink = 1;
2255                                        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2256                                        hostdata->connected = NULL;
2257                                        dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun));
2258                                        hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2259
2260                                        /* 
2261                                         * I'm not sure what the correct thing to do here is : 
2262                                         * 
2263                                         * If the command that just executed is NOT a request 
2264                                         * sense, the obvious thing to do is to set the result
2265                                         * code to the values of the stored parameters.
2266                                         * 
2267                                         * If it was a REQUEST SENSE command, we need some way 
2268                                         * to differentiate between the failure code of the original
2269                                         * and the failure code of the REQUEST sense - the obvious
2270                                         * case is success, where we fall through and leave the result
2271                                         * code unchanged.
2272                                         * 
2273                                         * The non-obvious place is where the REQUEST SENSE failed 
2274                                         */
2275
2276                                        if (cmd->cmnd[0] != REQUEST_SENSE)
2277                                                cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2278                                        else if (status_byte(cmd->SCp.Status) != GOOD)
2279                                                cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2280
2281#ifdef AUTOSENSE
2282                                        if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2283                                                hostdata->ses.cmd_len) {
2284                                                scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2285                                                hostdata->ses.cmd_len = 0 ;
2286                                        }
2287
2288                                        if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2289                                                scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2290
2291                                                dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));
2292
2293                                                LIST(cmd, hostdata->issue_queue);
2294                                                cmd->host_scribble = (unsigned char *)
2295                                                    hostdata->issue_queue;
2296                                                hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2297                                                dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no));
2298                                        } else
2299#endif                          /* def AUTOSENSE */
2300                                        {
2301                                                collect_stats(hostdata, cmd);
2302                                                cmd->scsi_done(cmd);
2303                                        }
2304
2305                                        NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2306                                        /* 
2307                                         * Restore phase bits to 0 so an interrupted selection, 
2308                                         * arbitration can resume.
2309                                         */
2310                                        NCR5380_write(TARGET_COMMAND_REG, 0);
2311
2312                                        while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2313                                                barrier();
2314                                        return;
2315                                case MESSAGE_REJECT:
2316                                        /* Accept message by clearing ACK */
2317                                        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2318                                        switch (hostdata->last_message) {
2319                                        case HEAD_OF_QUEUE_TAG:
2320                                        case ORDERED_QUEUE_TAG:
2321                                        case SIMPLE_QUEUE_TAG:
2322                                                cmd->device->simple_tags = 0;
2323                                                hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2324                                                break;
2325                                        default:
2326                                                break;
2327                                        }
2328                                case DISCONNECT:{
2329                                                /* Accept message by clearing ACK */
2330                                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2331                                                cmd->device->disconnect = 1;
2332                                                LIST(cmd, hostdata->disconnected_queue);
2333                                                cmd->host_scribble = (unsigned char *)
2334                                                    hostdata->disconnected_queue;
2335                                                hostdata->connected = NULL;
2336                                                hostdata->disconnected_queue = cmd;
2337                                                dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d lun %d was moved from connected to" "  the disconnected_queue\n", instance->host_no, cmd->device->id, cmd->device->lun));
2338                                                /* 
2339                                                 * Restore phase bits to 0 so an interrupted selection, 
2340                                                 * arbitration can resume.
2341                                                 */
2342                                                NCR5380_write(TARGET_COMMAND_REG, 0);
2343
2344                                                /* Enable reselect interrupts */
2345                                                NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2346                                                /* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/
2347                                                /* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */
2348                                                while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2349                                                        barrier();
2350                                                return;
2351                                        }
2352                                        /* 
2353                                         * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2354                                         * operation, in violation of the SCSI spec so we can safely 
2355                                         * ignore SAVE/RESTORE pointers calls.
2356                                         *
2357                                         * Unfortunately, some disks violate the SCSI spec and 
2358                                         * don't issue the required SAVE_POINTERS message before
2359                                         * disconnecting, and we have to break spec to remain 
2360                                         * compatible.
2361                                         */
2362                                case SAVE_POINTERS:
2363                                case RESTORE_POINTERS:
2364                                        /* Accept message by clearing ACK */
2365                                        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2366                                        break;
2367                                case EXTENDED_MESSAGE:
2368/* 
2369 * Extended messages are sent in the following format :
2370 * Byte         
2371 * 0            EXTENDED_MESSAGE == 1
2372 * 1            length (includes one byte for code, doesn't 
2373 *              include first two bytes)
2374 * 2            code
2375 * 3..length+1  arguments
2376 *
2377 * Start the extended message buffer with the EXTENDED_MESSAGE
2378 * byte, since spi_print_msg() wants the whole thing.  
2379 */
2380                                        extended_msg[0] = EXTENDED_MESSAGE;
2381                                        /* Accept first byte by clearing ACK */
2382                                        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2383                                        dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no));
2384
2385                                        len = 2;
2386                                        data = extended_msg + 1;
2387                                        phase = PHASE_MSGIN;
2388                                        NCR5380_transfer_pio(instance, &phase, &len, &data);
2389
2390                                        dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2]));
2391
2392                                        if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) {
2393                                                /* Accept third byte by clearing ACK */
2394                                                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2395                                                len = extended_msg[1] - 1;
2396                                                data = extended_msg + 3;
2397                                                phase = PHASE_MSGIN;
2398
2399                                                NCR5380_transfer_pio(instance, &phase, &len, &data);
2400                                                dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len));
2401
2402                                                switch (extended_msg[2]) {
2403                                                case EXTENDED_SDTR:
2404                                                case EXTENDED_WDTR:
2405                                                case EXTENDED_MODIFY_DATA_POINTER:
2406                                                case EXTENDED_EXTENDED_IDENTIFY:
2407                                                        tmp = 0;
2408                                                }
2409                                        } else if (len) {
2410                                                printk("scsi%d: error receiving extended message\n", instance->host_no);
2411                                                tmp = 0;
2412                                        } else {
2413                                                printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]);
2414                                                tmp = 0;
2415                                        }
2416                                        /* Fall through to reject message */
2417
2418                                        /* 
2419                                         * If we get something weird that we aren't expecting, 
2420                                         * reject it.
2421                                         */
2422                                default:
2423                                        if (!tmp) {
2424                                                printk("scsi%d: rejecting message ", instance->host_no);
2425                                                spi_print_msg(extended_msg);
2426                                                printk("\n");
2427                                        } else if (tmp != EXTENDED_MESSAGE)
2428                                                scmd_printk(KERN_INFO, cmd,
2429                                                        "rejecting unknown message %02x\n",tmp);
2430                                        else
2431                                                scmd_printk(KERN_INFO, cmd,
2432                                                        "rejecting unknown extended message code %02x, length %d\n", extended_msg[1], extended_msg[0]);
2433
2434                                        msgout = MESSAGE_REJECT;
2435                                        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2436                                        break;
2437                                }       /* switch (tmp) */
2438                                break;
2439                        case PHASE_MSGOUT:
2440                                len = 1;
2441                                data = &msgout;
2442                                hostdata->last_message = msgout;
2443                                NCR5380_transfer_pio(instance, &phase, &len, &data);
2444                                if (msgout == ABORT) {
2445                                        hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2446                                        hostdata->connected = NULL;
2447                                        cmd->result = DID_ERROR << 16;
2448                                        collect_stats(hostdata, cmd);
2449                                        cmd->scsi_done(cmd);
2450                                        NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2451                                        return;
2452                                }
2453                                msgout = NOP;
2454                                break;
2455                        case PHASE_CMDOUT:
2456                                len = cmd->cmd_len;
2457                                data = cmd->cmnd;
2458                                /* 
2459                                 * XXX for performance reasons, on machines with a 
2460                                 * PSEUDO-DMA architecture we should probably 
2461                                 * use the dma transfer function.  
2462                                 */
2463                                NCR5380_transfer_pio(instance, &phase, &len, &data);
2464                                if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) {
2465                                        NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2466                                        dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2467                                        return;
2468                                }
2469                                break;
2470                        case PHASE_STATIN:
2471                                len = 1;
2472                                data = &tmp;
2473                                NCR5380_transfer_pio(instance, &phase, &len, &data);
2474                                cmd->SCp.Status = tmp;
2475                                break;
2476                        default:
2477                                printk("scsi%d : unknown phase\n", instance->host_no);
2478                                NCR5380_dprint(NDEBUG_ALL, instance);
2479                        }       /* switch(phase) */
2480                }               /* if (tmp * SR_REQ) */
2481                else {
2482                        /* RvC: go to sleep if polling time expired
2483                         */
2484                        if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) {
2485                                NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2486                                dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2487                                return;
2488                        }
2489                }
2490        }                       /* while (1) */
2491}
2492
2493/*
2494 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2495 *
2496 * Purpose : does reselection, initializing the instance->connected 
2497 *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 
2498 *      nexus has been reestablished,
2499 *      
2500 * Inputs : instance - this instance of the NCR5380.
2501 *
2502 * Locks: io_request_lock held by caller if IRQ driven
2503 */
2504
2505static void NCR5380_reselect(struct Scsi_Host *instance) {
2506        NCR5380_local_declare();
2507        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)
2508         instance->hostdata;
2509        unsigned char target_mask;
2510        unsigned char lun, phase;
2511        int len;
2512        unsigned char msg[3];
2513        unsigned char *data;
2514        Scsi_Cmnd *tmp = NULL, *prev;
2515        int abort = 0;
2516        NCR5380_setup(instance);
2517
2518        /*
2519         * Disable arbitration, etc. since the host adapter obviously
2520         * lost, and tell an interrupted NCR5380_select() to restart.
2521         */
2522
2523        NCR5380_write(MODE_REG, MR_BASE);
2524        hostdata->restart_select = 1;
2525
2526        target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2527        dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no));
2528
2529        /* 
2530         * At this point, we have detected that our SCSI ID is on the bus,
2531         * SEL is true and BSY was false for at least one bus settle delay
2532         * (400 ns).
2533         *
2534         * We must assert BSY ourselves, until the target drops the SEL
2535         * signal.
2536         */
2537
2538        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2539
2540        /* FIXME: timeout too long, must fail to workqueue */   
2541        if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0)
2542                abort = 1;
2543                
2544        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2545
2546        /*
2547         * Wait for target to go into MSGIN.
2548         * FIXME: timeout needed and fail to work queeu
2549         */
2550
2551        if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ))
2552                abort = 1;
2553
2554        len = 1;
2555        data = msg;
2556        phase = PHASE_MSGIN;
2557        NCR5380_transfer_pio(instance, &phase, &len, &data);
2558
2559        if (!(msg[0] & 0x80)) {
2560                printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no);
2561                spi_print_msg(msg);
2562                abort = 1;
2563        } else {
2564                /* Accept message by clearing ACK */
2565                NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2566                lun = (msg[0] & 0x07);
2567
2568                /* 
2569                 * We need to add code for SCSI-II to track which devices have
2570                 * I_T_L_Q nexuses established, and which have simple I_T_L
2571                 * nexuses so we can chose to do additional data transfer.
2572                 */
2573
2574                /* 
2575                 * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we 
2576                 * just reestablished, and remove it from the disconnected queue.
2577                 */
2578
2579
2580                for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
2581                        if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2582                            ) {
2583                                if (prev) {
2584                                        REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
2585                                        prev->host_scribble = tmp->host_scribble;
2586                                } else {
2587                                        REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble);
2588                                        hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble;
2589                                }
2590                                tmp->host_scribble = NULL;
2591                                break;
2592                        }
2593                if (!tmp) {
2594                        printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun);
2595                        /* 
2596                         * Since we have an established nexus that we can't do anything with,
2597                         * we must abort it.  
2598                         */
2599                        abort = 1;
2600                }
2601        }
2602
2603        if (abort) {
2604                do_abort(instance);
2605        } else {
2606                hostdata->connected = tmp;
2607                dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag));
2608        }
2609}
2610
2611/*
2612 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
2613 *
2614 * Purpose : called by interrupt handler when DMA finishes or a phase
2615 *      mismatch occurs (which would finish the DMA transfer).  
2616 *
2617 * Inputs : instance - this instance of the NCR5380.
2618 *
2619 * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L
2620 *      nexus has been reestablished, on failure NULL is returned.
2621 */
2622
2623#ifdef REAL_DMA
2624static void NCR5380_dma_complete(NCR5380_instance * instance) {
2625        NCR5380_local_declare();
2626        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2627        int transferred;
2628        NCR5380_setup(instance);
2629
2630        /*
2631         * XXX this might not be right.
2632         *
2633         * Wait for final byte to transfer, ie wait for ACK to go false.
2634         *
2635         * We should use the Last Byte Sent bit, unfortunately this is 
2636         * not available on the 5380/5381 (only the various CMOS chips)
2637         *
2638         * FIXME: timeout, and need to handle long timeout/irq case
2639         */
2640
2641        NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);
2642
2643        NCR5380_write(MODE_REG, MR_BASE);
2644        NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2645
2646        /*
2647         * The only places we should see a phase mismatch and have to send
2648         * data from the same set of pointers will be the data transfer
2649         * phases.  So, residual, requested length are only important here.
2650         */
2651
2652        if (!(hostdata->connected->SCp.phase & SR_CD)) {
2653                transferred = instance->dmalen - NCR5380_dma_residual();
2654                hostdata->connected->SCp.this_residual -= transferred;
2655                hostdata->connected->SCp.ptr += transferred;
2656        }
2657}
2658#endif                          /* def REAL_DMA */
2659
2660/*
2661 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2662 *
2663 * Purpose : abort a command
2664 *
2665 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 
2666 *      host byte of the result field to, if zero DID_ABORTED is 
2667 *      used.
2668 *
2669 * Returns : 0 - success, -1 on failure.
2670 *
2671 *      XXX - there is no way to abort the command that is currently 
2672 *      connected, you have to wait for it to complete.  If this is 
2673 *      a problem, we could implement longjmp() / setjmp(), setjmp()
2674 *      called where the loop started in NCR5380_main().
2675 *
2676 * Locks: host lock taken by caller
2677 */
2678
2679static int NCR5380_abort(Scsi_Cmnd * cmd) {
2680        NCR5380_local_declare();
2681        struct Scsi_Host *instance = cmd->device->host;
2682        struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2683        Scsi_Cmnd *tmp, **prev;
2684        
2685        printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no);
2686        scsi_print_command(cmd);
2687
2688        NCR5380_print_status(instance);
2689
2690        NCR5380_setup(instance);
2691
2692        dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no));
2693        dprintk(NDEBUG_ABORT, ("        basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)));
2694
2695#if 0
2696/*
2697 * Case 1 : If the command is the currently executing command, 
2698 * we'll set the aborted flag and return control so that 
2699 * information transfer routine can exit cleanly.
2700 */
2701
2702        if (hostdata->connected == cmd) {
2703                dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no));
2704                hostdata->aborted = 1;
2705/*
2706 * We should perform BSY checking, and make sure we haven't slipped
2707 * into BUS FREE.
2708 */
2709
2710                NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN);
2711/* 
2712 * Since we can't change phases until we've completed the current 
2713 * handshake, we have to source or sink a byte of data if the current
2714 * phase is not MSGOUT.
2715 */
2716
2717/* 
2718 * Return control to the executing NCR drive so we can clear the
2719 * aborted flag and get back into our main loop.
2720 */
2721
2722                return 0;
2723        }
2724#endif
2725
2726/* 
2727 * Case 2 : If the command hasn't been issued yet, we simply remove it 
2728 *          from the issue queue.
2729 */
2730 
2731        dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no));
2732        for (prev = (Scsi_Cmnd **) & (hostdata->issue_queue), tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
2733                if (cmd == tmp) {
2734                        REMOVE(5, *prev, tmp, tmp->host_scribble);
2735                        (*prev) = (Scsi_Cmnd *) tmp->host_scribble;
2736                        tmp->host_scribble = NULL;
2737                        tmp->result = DID_ABORT << 16;
2738                        dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no));
2739                        tmp->scsi_done(tmp);
2740                        return SUCCESS;
2741                }
2742#if (NDEBUG  & NDEBUG_ABORT)
2743        /* KLL */
2744                else if (prev == tmp)
2745                        printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no);
2746#endif
2747
2748/* 
2749 * Case 3 : If any commands are connected, we're going to fail the abort
2750 *          and let the high level SCSI driver retry at a later time or 
2751 *          issue a reset.
2752 *
2753 *          Timeouts, and therefore aborted commands, will be highly unlikely
2754 *          and handling them cleanly in this situation would make the common
2755 *          case of noresets less efficient, and would pollute our code.  So,
2756 *          we fail.
2757 */
2758
2759        if (hostdata->connected) {
2760                dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no));
2761                return FAILED;
2762        }
2763/*
2764 * Case 4: If the command is currently disconnected from the bus, and 
2765 *      there are no connected commands, we reconnect the I_T_L or 
2766 *      I_T_L_Q nexus associated with it, go into message out, and send 
2767 *      an abort message.
2768 *
2769 * This case is especially ugly. In order to reestablish the nexus, we
2770 * need to call NCR5380_select().  The easiest way to implement this 
2771 * function was to abort if the bus was busy, and let the interrupt
2772 * handler triggered on the SEL for reselect take care of lost arbitrations
2773 * where necessary, meaning interrupts need to be enabled.
2774 *
2775 * When interrupts are enabled, the queues may change - so we 
2776 * can't remove it from the disconnected queue before selecting it
2777 * because that could cause a failure in hashing the nexus if that 
2778 * device reselected.
2779 * 
2780 * Since the queues may change, we can't use the pointers from when we
2781 * first locate it.
2782 *
2783 * So, we must first locate the command, and if NCR5380_select()
2784 * succeeds, then issue the abort, relocate the command and remove
2785 * it from the disconnected queue.
2786 */
2787
2788        for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble)
2789                if (cmd == tmp) {
2790                        dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no));
2791
2792                        if (NCR5380_select(instance, cmd, (int) cmd->tag))
2793                                return FAILED;
2794                        dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no));
2795
2796                        do_abort(instance);
2797
2798                        for (prev = (Scsi_Cmnd **) & (hostdata->disconnected_queue), tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
2799                                if (cmd == tmp) {
2800                                        REMOVE(5, *prev, tmp, tmp->host_scribble);
2801                                        *prev = (Scsi_Cmnd *) tmp->host_scribble;
2802                                        tmp->host_scribble = NULL;
2803                                        tmp->result = DID_ABORT << 16;
2804                                        tmp->scsi_done(tmp);
2805                                        return SUCCESS;
2806                                }
2807                }
2808/*
2809 * Case 5 : If we reached this point, the command was not found in any of 
2810 *          the queues.
2811 *
2812 * We probably reached this point because of an unlikely race condition
2813 * between the command completing successfully and the abortion code,
2814 * so we won't panic, but we will notify the user in case something really
2815 * broke.
2816 */
2817        printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n"
2818                        "         before abortion\n", instance->host_no);
2819        return FAILED;
2820}
2821
2822
2823/* 
2824 * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd)
2825 * 
2826 * Purpose : reset the SCSI bus.
2827 *
2828 * Returns : SUCCESS
2829 *
2830 * Locks: host lock taken by caller
2831 */
2832
2833static int NCR5380_bus_reset(Scsi_Cmnd * cmd)
2834{
2835        struct Scsi_Host *instance = cmd->device->host;
2836
2837        NCR5380_local_declare();
2838        NCR5380_setup(instance);
2839        NCR5380_print_status(instance);
2840
2841        spin_lock_irq(instance->host_lock);
2842        do_reset(instance);
2843        spin_unlock_irq(instance->host_lock);
2844
2845        return SUCCESS;
2846}
2847
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