drivers/scsi/seagate.c

   1 /*
   2  *    seagate.c Copyright (C) 1992, 1993 Drew Eckhardt
   3  *      low level scsi driver for ST01/ST02, Future Domain TMC-885,
   4  *      TMC-950 by Drew Eckhardt <drew@colorado.edu>
   5  *
   6  *      Note : TMC-880 boards don't work because they have two bits in
   7  *              the status register flipped, I'll fix this "RSN"
   8  *      [why do I have strong feeling that above message is from 1993? :-)
   9  *              pavel@ucw.cz]
  10  *
  11  *      This card does all the I/O via memory mapped I/O, so there is no need
  12  *      to check or allocate a region of the I/O address space.
  13  */
  14
  15 /* 1996 - to use new read{b,w,l}, write{b,w,l}, and phys_to_virt
  16  * macros, replaced assembler routines with C. There's probably a
  17  * performance hit, but I only have a cdrom and can't tell. Define
  18  * SEAGATE_USE_ASM if you want the old assembler code -- SJT
  19  *
  20  * 1998-jul-29 - created DPRINTK macros and made it work under
  21  * linux 2.1.112, simplified some #defines etc. <pavel@ucw.cz>
  22  *
  23  * Aug 2000 - aeb - deleted seagate_st0x_biosparam(). It would try to
  24  * read the physical disk geometry, a bad mistake. Of course it doesn't
  25  * matter much what geometry one invents, but on large disks it
  26  * returned 256 (or more) heads, causing all kind of failures.
  27  * Of course this means that people might see a different geometry now,
  28  * so boot parameters may be necessary in some cases.
  29  */
  30
  31 /*
  32  * Configuration :
  33  * To use without BIOS -DOVERRIDE=base_address -DCONTROLLER=FD or SEAGATE
  34  * -DIRQ will override the default of 5.
  35  * Note: You can now set these options from the kernel's "command line".
  36  * The syntax is:
  37  *
  38  *     st0x=ADDRESS,IRQ                (for a Seagate controller)
  39  * or:
  40  *     tmc8xx=ADDRESS,IRQ              (for a TMC-8xx or TMC-950 controller)
  41  * eg:
  42  *     tmc8xx=0xC8000,15
  43  *
  44  * will configure the driver for a TMC-8xx style controller using IRQ 15
  45  * with a base address of 0xC8000.
  46  *
  47  * -DARBITRATE
  48  *      Will cause the host adapter to arbitrate for the
  49  *      bus for better SCSI-II compatibility, rather than just
  50  *      waiting for BUS FREE and then doing its thing.  Should
  51  *      let us do one command per Lun when I integrate my
  52  *      reorganization changes into the distribution sources.
  53  *
  54  * -DDEBUG=65535
  55  *      Will activate debug code.
  56  *
  57  * -DFAST or -DFAST32
  58  *      Will use blind transfers where possible
  59  *
  60  * -DPARITY
  61  *      This will enable parity.
  62  *
  63  * -DSEAGATE_USE_ASM
  64  *      Will use older seagate assembly code. should be (very small amount)
  65  *      Faster.
  66  *
  67  * -DSLOW_RATE=50
  68  *      Will allow compatibility with broken devices that don't
  69  *      handshake fast enough (ie, some CD ROM's) for the Seagate
  70  *      code.
  71  *
  72  *      50 is some number, It will let you specify a default
  73  *      transfer rate if handshaking isn't working correctly.
  74  *
  75  * -DOLDCNTDATASCEME  There is a new sceme to set the CONTROL
  76  *                    and DATA reigsters which complies more closely
  77  *                    with the SCSI2 standard. This hopefully eliminates
  78  *                    the need to swap the order these registers are
  79  *                    'messed' with. It makes the following two options
  80  *                    obsolete. To reenable the old sceme define this.
  81  *
  82  * The following to options are patches from the SCSI.HOWTO
  83  *
  84  * -DSWAPSTAT  This will swap the definitions for STAT_MSG and STAT_CD.
  85  *
  86  * -DSWAPCNTDATA  This will swap the order that seagate.c messes with
  87  *                the CONTROL an DATA registers.
  88  */
  89
  90 #include <linux/module.h>
  91 #include <linux/interrupt.h>
  92 #include <linux/spinlock.h>
  93 #include <linux/signal.h>
  94 #include <linux/string.h>
  95 #include <linux/proc_fs.h>
  96 #include <linux/init.h>
  97 #include <linux/blkdev.h>
  98 #include <linux/stat.h>
  99 #include <linux/delay.h>
 100 #include <linux/io.h>
 101
 102 #include <asm/system.h>
 103 #include <asm/uaccess.h>
 104
 105 #include <scsi/scsi_cmnd.h>
 106 #include <scsi/scsi_device.h>
 107 #include <scsi/scsi.h>
 108
 109 #include <scsi/scsi_dbg.h>
 110 #include <scsi/scsi_host.h>
 111
 112
 113 #ifdef DEBUG
 114 #define DPRINTK( when, msg... ) do { if ( (DEBUG & (when)) == (when) ) printk( msg ); } while (0)
 115 #else
 116 #define DPRINTK( when, msg... ) do { } while (0)
 117 #define DEBUG 0
 118 #endif
 119 #define DANY( msg... ) DPRINTK( 0xffff, msg );
 120
 121 #ifndef IRQ
 122 #define IRQ 5
 123 #endif
 124
 125 #ifdef FAST32
 126 #define FAST
 127 #endif
 128
 129 #undef LINKED                   /* Linked commands are currently broken! */
 130
 131 #if defined(OVERRIDE) && !defined(CONTROLLER)
 132 #error Please use -DCONTROLLER=SEAGATE or -DCONTROLLER=FD to override controller type
 133 #endif
 134
 135 #ifndef __i386__
 136 #undef SEAGATE_USE_ASM
 137 #endif
 138
 139 /*
 140         Thanks to Brian Antoine for the example code in his Messy-Loss ST-01
 141                 driver, and Mitsugu Suzuki for information on the ST-01
 142                 SCSI host.
 143 */
 144
 145 /*
 146         CONTROL defines
 147 */
 148
 149 #define CMD_RST                 0x01
 150 #define CMD_SEL                 0x02
 151 #define CMD_BSY                 0x04
 152 #define CMD_ATTN                0x08
 153 #define CMD_START_ARB           0x10
 154 #define CMD_EN_PARITY           0x20
 155 #define CMD_INTR                0x40
 156 #define CMD_DRVR_ENABLE         0x80
 157
 158 /*
 159         STATUS
 160 */
 161 #ifdef SWAPSTAT
 162 #define STAT_MSG                0x08
 163 #define STAT_CD                 0x02
 164 #else
 165 #define STAT_MSG                0x02
 166 #define STAT_CD                 0x08
 167 #endif
 168
 169 #define STAT_BSY                0x01
 170 #define STAT_IO                 0x04
 171 #define STAT_REQ                0x10
 172 #define STAT_SEL                0x20
 173 #define STAT_PARITY             0x40
 174 #define STAT_ARB_CMPL           0x80
 175
 176 /*
 177         REQUESTS
 178 */
 179
 180 #define REQ_MASK (STAT_CD |  STAT_IO | STAT_MSG)
 181 #define REQ_DATAOUT 0
 182 #define REQ_DATAIN STAT_IO
 183 #define REQ_CMDOUT STAT_CD
 184 #define REQ_STATIN (STAT_CD | STAT_IO)
 185 #define REQ_MSGOUT (STAT_MSG | STAT_CD)
 186 #define REQ_MSGIN (STAT_MSG | STAT_CD | STAT_IO)
 187
 188 extern volatile int seagate_st0x_timeout;
 189
 190 #ifdef PARITY
 191 #define BASE_CMD CMD_EN_PARITY
 192 #else
 193 #define BASE_CMD  0
 194 #endif
 195
 196 /*
 197         Debugging code
 198 */
 199
 200 #define PHASE_BUS_FREE 1
 201 #define PHASE_ARBITRATION 2
 202 #define PHASE_SELECTION 4
 203 #define PHASE_DATAIN 8
 204 #define PHASE_DATAOUT 0x10
 205 #define PHASE_CMDOUT 0x20
 206 #define PHASE_MSGIN 0x40
 207 #define PHASE_MSGOUT 0x80
 208 #define PHASE_STATUSIN 0x100
 209 #define PHASE_ETC (PHASE_DATAIN | PHASE_DATAOUT | PHASE_CMDOUT | PHASE_MSGIN | PHASE_MSGOUT | PHASE_STATUSIN)
 210 #define PRINT_COMMAND 0x200
 211 #define PHASE_EXIT 0x400
 212 #define PHASE_RESELECT 0x800
 213 #define DEBUG_FAST 0x1000
 214 #define DEBUG_SG   0x2000
 215 #define DEBUG_LINKED    0x4000
 216 #define DEBUG_BORKEN    0x8000
 217
 218 /*
 219  *      Control options - these are timeouts specified in .01 seconds.
 220  */
 221
 222 /* 30, 20 work */
 223 #define ST0X_BUS_FREE_DELAY 25
 224 #define ST0X_SELECTION_DELAY 25
 225
 226 #define SEAGATE 1               /* these determine the type of the controller */
 227 #define FD      2
 228
 229 #define ST0X_ID_STR     "Seagate ST-01/ST-02"
 230 #define FD_ID_STR       "TMC-8XX/TMC-950"
 231
 232 static int internal_command (unsigned char target, unsigned char lun,
 233                              const void *cmnd,
 234                              void *buff, int bufflen, int reselect);
 235
 236 static int incommand;           /* set if arbitration has finished
 237                                    and we are in some command phase. */
 238
 239 static unsigned int base_address = 0;   /* Where the card ROM starts, used to
 240                                            calculate memory mapped register
 241                                            location.  */
 242
 243 static void __iomem *st0x_cr_sr;        /* control register write, status
 244                                            register read.  256 bytes in
 245                                            length.
 246                                            Read is status of SCSI BUS, as per
 247                                            STAT masks.  */
 248
 249 static void __iomem *st0x_dr;   /* data register, read write 256
 250                                    bytes in length.  */
 251
 252 static volatile int st0x_aborted = 0;   /* set when we are aborted, ie by a
 253                                            time out, etc.  */
 254
 255 static unsigned char controller_type = 0;       /* set to SEAGATE for ST0x
 256                                                    boards or FD for TMC-8xx
 257                                                    boards */
 258 static int irq = IRQ;
 259
 260 module_param(base_address, uint, 0);
 261 module_param(controller_type, byte, 0);
 262 module_param(irq, int, 0);
 263 MODULE_LICENSE("GPL");
 264
 265
 266 #define retcode(result) (((result) << 16) | (message << 8) | status)
 267 #define STATUS ((u8) readb(st0x_cr_sr))
 268 #define DATA ((u8) readb(st0x_dr))
 269 #define WRITE_CONTROL(d) { writeb((d), st0x_cr_sr); }
 270 #define WRITE_DATA(d) { writeb((d), st0x_dr); }
 271
 272 #ifndef OVERRIDE
 273 static unsigned int seagate_bases[] = {
 274         0xc8000, 0xca000, 0xcc000,
 275         0xce000, 0xdc000, 0xde000
 276 };
 277
 278 typedef struct {
 279         const unsigned char *signature;
 280         unsigned offset;
 281         unsigned length;
 282         unsigned char type;
 283 } Signature;
 284
 285 static Signature __initdata signatures[] = {
 286         {"ST01 v1.7  (C) Copyright 1987 Seagate", 15, 37, SEAGATE},
 287         {"SCSI BIOS 2.00  (C) Copyright 1987 Seagate", 15, 40, SEAGATE},
 288
 289 /*
 290  * The following two lines are NOT mistakes.  One detects ROM revision
 291  * 3.0.0, the other 3.2.  Since seagate has only one type of SCSI adapter,
 292  * and this is not going to change, the "SEAGATE" and "SCSI" together
 293  * are probably "good enough"
 294  */
 295
 296         {"SEAGATE SCSI BIOS ", 16, 17, SEAGATE},
 297         {"SEAGATE SCSI BIOS ", 17, 17, SEAGATE},
 298
 299 /*
 300  * However, future domain makes several incompatible SCSI boards, so specific
 301  * signatures must be used.
 302  */
 303
 304         {"FUTURE DOMAIN CORP. (C) 1986-1989 V5.0C2/14/89", 5, 46, FD},
 305         {"FUTURE DOMAIN CORP. (C) 1986-1989 V6.0A7/28/89", 5, 46, FD},
 306         {"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0105/31/90", 5, 47, FD},
 307         {"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0209/18/90", 5, 47, FD},
 308         {"FUTURE DOMAIN CORP. (C) 1986-1990 V7.009/18/90", 5, 46, FD},
 309         {"FUTURE DOMAIN CORP. (C) 1992 V8.00.004/02/92", 5, 44, FD},
 310         {"IBM F1 BIOS V1.1004/30/92", 5, 25, FD},
 311         {"FUTURE DOMAIN TMC-950", 5, 21, FD},
 312         /* Added for 2.2.16 by Matthias_Heidbrink@b.maus.de */
 313         {"IBM F1 V1.2009/22/93", 5, 25, FD},
 314 };
 315
 316 #define NUM_SIGNATURES ARRAY_SIZE(signatures)
 317 #endif                          /* n OVERRIDE */
 318
 319 /*
 320  * hostno stores the hostnumber, as told to us by the init routine.
 321  */
 322
 323 static int hostno = -1;
 324 static void seagate_reconnect_intr (int, void *);
 325 static irqreturn_t do_seagate_reconnect_intr (int, void *);
 326 static int seagate_st0x_bus_reset(struct scsi_cmnd *);
 327
 328 #ifdef FAST
 329 static int fast = 1;
 330 #else
 331 #define fast 0
 332 #endif
 333
 334 #ifdef SLOW_RATE
 335 /*
 336  * Support for broken devices :
 337  * The Seagate board has a handshaking problem.  Namely, a lack
 338  * thereof for slow devices.  You can blast 600K/second through
 339  * it if you are polling for each byte, more if you do a blind
 340  * transfer.  In the first case, with a fast device, REQ will
 341  * transition high-low or high-low-high before your loop restarts
 342  * and you'll have no problems.  In the second case, the board
 343  * will insert wait states for up to 13.2 usecs for REQ to
 344  * transition low->high, and everything will work.
 345  *
 346  * However, there's nothing in the state machine that says
 347  * you *HAVE* to see a high-low-high set of transitions before
 348  * sending the next byte, and slow things like the Trantor CD ROMS
 349  * will break because of this.
 350  *
 351  * So, we need to slow things down, which isn't as simple as it
 352  * seems.  We can't slow things down period, because then people
 353  * who don't recompile their kernels will shoot me for ruining
 354  * their performance.  We need to do it on a case per case basis.
 355  *
 356  * The best for performance will be to, only for borken devices
 357  * (this is stored on a per-target basis in the scsi_devices array)
 358  *
 359  * Wait for a low->high transition before continuing with that
 360  * transfer.  If we timeout, continue anyways.  We don't need
 361  * a long timeout, because REQ should only be asserted until the
 362  * corresponding ACK is received and processed.
 363  *
 364  * Note that we can't use the system timer for this, because of
 365  * resolution, and we *really* can't use the timer chip since
 366  * gettimeofday() and the beeper routines use that.  So,
 367  * the best thing for us to do will be to calibrate a timing
 368  * loop in the initialization code using the timer chip before
 369  * gettimeofday() can screw with it.
 370  *
 371  * FIXME: this is broken (not borken :-). Empty loop costs less than
 372  * loop with ISA access in it! -- pavel@ucw.cz
 373  */
 374
 375 static int borken_calibration = 0;
 376
 377 static void __init borken_init (void)
 378 {
 379         register int count = 0, start = jiffies + 1, stop = start + 25;
 380
 381         /* FIXME: There may be a better approach, this is a straight port for
 382            now */
 383         preempt_disable();
 384         while (time_before (jiffies, start))
 385                 cpu_relax();
 386         for (; time_before (jiffies, stop); ++count)
 387                 cpu_relax();
 388         preempt_enable();
 389
 390 /*
 391  * Ok, we now have a count for .25 seconds.  Convert to a
 392  * count per second and divide by transfer rate in K.  */
 393
 394         borken_calibration = (count * 4) / (SLOW_RATE * 1024);
 395
 396         if (borken_calibration < 1)
 397                 borken_calibration = 1;
 398 }
 399
 400 static inline void borken_wait (void)
 401 {
 402         register int count;
 403
 404         for (count = borken_calibration; count && (STATUS & STAT_REQ); --count)
 405                 cpu_relax();
 406
 407 #if (DEBUG & DEBUG_BORKEN)
 408         if (count)
 409                 printk ("scsi%d : borken timeout\n", hostno);
 410 #endif
 411 }
 412
 413 #endif                          /* def SLOW_RATE */
 414
 415 /* These beasts only live on ISA, and ISA means 8MHz. Each ULOOP()
 416  * contains at least one ISA access, which takes more than 0.125
 417  * usec. So if we loop 8 times time in usec, we are safe.
 418  */
 419
 420 #define ULOOP( i ) for (clock = i*8;;)
 421 #define TIMEOUT (!(clock--))
 422
 423 static int __init seagate_st0x_detect (struct scsi_host_template * tpnt)
 424 {
 425         struct Scsi_Host *instance;
 426         int i, j;
 427         unsigned long cr, dr;
 428
 429         tpnt->proc_name = "seagate";
 430 /*
 431  *      First, we try for the manual override.
 432  */
 433         DANY ("Autodetecting ST0x / TMC-8xx\n");
 434
 435         if (hostno != -1) {
 436                 printk (KERN_ERR "seagate_st0x_detect() called twice?!\n");
 437                 return 0;
 438         }
 439
 440 /* If the user specified the controller type from the command line,
 441    controller_type will be non-zero, so don't try to detect one */
 442
 443         if (!controller_type) {
 444 #ifdef OVERRIDE
 445                 base_address = OVERRIDE;
 446                 controller_type = CONTROLLER;
 447
 448                 DANY ("Base address overridden to %x, controller type is %s\n",
 449                       base_address,
 450                       controller_type == SEAGATE ? "SEAGATE" : "FD");
 451 #else                           /* OVERRIDE */
 452 /*
 453  *      To detect this card, we simply look for the signature
 454  *      from the BIOS version notice in all the possible locations
 455  *      of the ROM's.  This has a nice side effect of not trashing
 456  *      any register locations that might be used by something else.
 457  *
 458  * XXX - note that we probably should be probing the address
 459  * space for the on-board RAM instead.
 460  */
 461
 462                 for (i = 0; i < ARRAY_SIZE(seagate_bases); ++i) {
 463                         void __iomem *p = ioremap(seagate_bases[i], 0x2000);
 464                         if (!p)
 465                                 continue;
 466                         for (j = 0; j < NUM_SIGNATURES; ++j)
 467                                 if (check_signature(p + signatures[j].offset, signatures[j].signature, signatures[j].length)) {
 468                                         base_address = seagate_bases[i];
 469                                         controller_type = signatures[j].type;
 470                                         break;
 471                                 }
 472                         iounmap(p);
 473                 }
 474 #endif                          /* OVERRIDE */
 475         }
 476         /* (! controller_type) */
 477         tpnt->this_id = (controller_type == SEAGATE) ? 7 : 6;
 478         tpnt->name = (controller_type == SEAGATE) ? ST0X_ID_STR : FD_ID_STR;
 479
 480         if (!base_address) {
 481                 printk(KERN_INFO "seagate: ST0x/TMC-8xx not detected.\n");
 482                 return 0;
 483         }
 484
 485         cr = base_address + (controller_type == SEAGATE ? 0x1a00 : 0x1c00);
 486         dr = cr + 0x200;
 487         st0x_cr_sr = ioremap(cr, 0x100);
 488         st0x_dr = ioremap(dr, 0x100);
 489
 490         DANY("%s detected. Base address = %x, cr = %x, dr = %x\n",
 491               tpnt->name, base_address, cr, dr);
 492
 493         /*
 494          *      At all times, we will use IRQ 5.  Should also check for IRQ3
 495          *      if we lose our first interrupt.
 496          */
 497         instance = scsi_register (tpnt, 0);
 498         if (instance == NULL)
 499                 return 0;
 500
 501         hostno = instance->host_no;
 502         if (request_irq (irq, do_seagate_reconnect_intr, IRQF_DISABLED, (controller_type == SEAGATE) ? "seagate" : "tmc-8xx", instance)) {
 503                 printk(KERN_ERR "scsi%d : unable to allocate IRQ%d\n", hostno, irq);
 504                 return 0;
 505         }
 506         instance->irq = irq;
 507         instance->io_port = base_address;
 508 #ifdef SLOW_RATE
 509         printk(KERN_INFO "Calibrating borken timer... ");
 510         borken_init();
 511         printk(" %d cycles per transfer\n", borken_calibration);
 512 #endif
 513         printk (KERN_INFO "This is one second... ");
 514         {
 515                 int clock;
 516                 ULOOP (1 * 1000 * 1000) {
 517                         STATUS;
 518                         if (TIMEOUT)
 519                                 break;
 520                 }
 521         }
 522
 523         printk ("done, %s options:"
 524 #ifdef ARBITRATE
 525                 " ARBITRATE"
 526 #endif
 527 #if DEBUG
 528                 " DEBUG"
 529 #endif
 530 #ifdef FAST
 531                 " FAST"
 532 #ifdef FAST32
 533                 "32"
 534 #endif
 535 #endif
 536 #ifdef LINKED
 537                 " LINKED"
 538 #endif
 539 #ifdef PARITY
 540                 " PARITY"
 541 #endif
 542 #ifdef SEAGATE_USE_ASM
 543                 " SEAGATE_USE_ASM"
 544 #endif
 545 #ifdef SLOW_RATE
 546                 " SLOW_RATE"
 547 #endif
 548 #ifdef SWAPSTAT
 549                 " SWAPSTAT"
 550 #endif
 551 #ifdef SWAPCNTDATA
 552                 " SWAPCNTDATA"
 553 #endif
 554                 "\n", tpnt->name);
 555         return 1;
 556 }
 557
 558 static const char *seagate_st0x_info (struct Scsi_Host *shpnt)
 559 {
 560         static char buffer[64];
 561
 562         snprintf(buffer, 64, "%s at irq %d, address 0x%05X",
 563                  (controller_type == SEAGATE) ? ST0X_ID_STR : FD_ID_STR,
 564                  irq, base_address);
 565         return buffer;
 566 }
 567
 568 /*
 569  * These are our saved pointers for the outstanding command that is
 570  * waiting for a reconnect
 571  */
 572
 573 static unsigned char current_target, current_lun;
 574 static unsigned char *current_cmnd, *current_data;
 575 static int current_nobuffs;
 576 static struct scatterlist *current_buffer;
 577 static int current_bufflen;
 578
 579 #ifdef LINKED
 580 /*
 581  * linked_connected indicates whether or not we are currently connected to
 582  * linked_target, linked_lun and in an INFORMATION TRANSFER phase,
 583  * using linked commands.
 584  */
 585
 586 static int linked_connected = 0;
 587 static unsigned char linked_target, linked_lun;
 588 #endif
 589
 590 static void (*done_fn) (struct scsi_cmnd *) = NULL;
 591 static struct scsi_cmnd *SCint = NULL;
 592
 593 /*
 594  * These control whether or not disconnect / reconnect will be attempted,
 595  * or are being attempted.
 596  */
 597
 598 #define NO_RECONNECT    0
 599 #define RECONNECT_NOW   1
 600 #define CAN_RECONNECT   2
 601
 602 /*
 603  * LINKED_RIGHT indicates that we are currently connected to the correct target
 604  * for this command, LINKED_WRONG indicates that we are connected to the wrong
 605  * target. Note that these imply CAN_RECONNECT and require defined(LINKED).
 606  */
 607
 608 #define LINKED_RIGHT    3
 609 #define LINKED_WRONG    4
 610
 611 /*
 612  * This determines if we are expecting to reconnect or not.
 613  */
 614
 615 static int should_reconnect = 0;
 616
 617 /*
 618  * The seagate_reconnect_intr routine is called when a target reselects the
 619  * host adapter.  This occurs on the interrupt triggered by the target
 620  * asserting SEL.
 621  */
 622
 623 static irqreturn_t do_seagate_reconnect_intr(int irq, void *dev_id)
 624 {
 625         unsigned long flags;
 626         struct Scsi_Host *dev = dev_id;
 627
 628         spin_lock_irqsave (dev->host_lock, flags);
 629         seagate_reconnect_intr (irq, dev_id);
 630         spin_unlock_irqrestore (dev->host_lock, flags);
 631         return IRQ_HANDLED;
 632 }
 633
 634 static void seagate_reconnect_intr (int irq, void *dev_id)
 635 {
 636         int temp;
 637         struct scsi_cmnd *SCtmp;
 638
 639         DPRINTK (PHASE_RESELECT, "scsi%d : seagate_reconnect_intr() called\n", hostno);
 640
 641         if (!should_reconnect)
 642                 printk(KERN_WARNING "scsi%d: unexpected interrupt.\n", hostno);
 643         else {
 644                 should_reconnect = 0;
 645
 646                 DPRINTK (PHASE_RESELECT, "scsi%d : internal_command(%d, %08x, %08x, RECONNECT_NOW\n",
 647                         hostno, current_target, current_data, current_bufflen);
 648
 649                 temp = internal_command (current_target, current_lun, current_cmnd, current_data, current_bufflen, RECONNECT_NOW);
 650
 651                 if (msg_byte(temp) != DISCONNECT) {
 652                         if (done_fn) {
 653                                 DPRINTK(PHASE_RESELECT, "scsi%d : done_fn(%d,%08x)", hostno, hostno, temp);
 654                                 if (!SCint)
 655                                         panic ("SCint == NULL in seagate");
 656                                 SCtmp = SCint;
 657                                 SCint = NULL;
 658                                 SCtmp->result = temp;
 659                                 done_fn(SCtmp);
 660                         } else
 661                                 printk(KERN_ERR "done_fn() not defined.\n");
 662                 }
 663         }
 664 }
 665
 666 /*
 667  * The seagate_st0x_queue_command() function provides a queued interface
 668  * to the seagate SCSI driver.  Basically, it just passes control onto the
 669  * seagate_command() function, after fixing it so that the done_fn()
 670  * is set to the one passed to the function.  We have to be very careful,
 671  * because there are some commands on some devices that do not disconnect,
 672  * and if we simply call the done_fn when the command is done then another
 673  * command is started and queue_command is called again...  We end up
 674  * overflowing the kernel stack, and this tends not to be such a good idea.
 675  */
 676
 677 static int recursion_depth = 0;
 678
 679 static int seagate_st0x_queue_command(struct scsi_cmnd * SCpnt,
 680                                       void (*done) (struct scsi_cmnd *))
 681 {
 682         int result, reconnect;
 683         struct scsi_cmnd *SCtmp;
 684
 685         DANY ("seagate: que_command");
 686         done_fn = done;
 687         current_target = SCpnt->device->id;
 688         current_lun = SCpnt->device->lun;
 689         current_cmnd = SCpnt->cmnd;
 690         current_data = (unsigned char *) SCpnt->request_buffer;
 691         current_bufflen = SCpnt->request_bufflen;
 692         SCint = SCpnt;
 693         if (recursion_depth)
 694                 return 1;
 695         recursion_depth++;
 696         do {
 697 #ifdef LINKED
 698                 /*
 699                  * Set linked command bit in control field of SCSI command.
 700                  */
 701
 702                 current_cmnd[SCpnt->cmd_len] |= 0x01;
 703                 if (linked_connected) {
 704                         DPRINTK (DEBUG_LINKED, "scsi%d : using linked commands, current I_T_L nexus is ", hostno);
 705                         if (linked_target == current_target && linked_lun == current_lun)
 706                         {
 707                                 DPRINTK(DEBUG_LINKED, "correct\n");
 708                                 reconnect = LINKED_RIGHT;
 709                         } else {
 710                                 DPRINTK(DEBUG_LINKED, "incorrect\n");
 711                                 reconnect = LINKED_WRONG;
 712                         }
 713                 } else
 714 #endif                          /* LINKED */
 715                         reconnect = CAN_RECONNECT;
 716
 717                 result = internal_command(SCint->device->id, SCint->device->lun, SCint->cmnd,
 718                                       SCint->request_buffer, SCint->request_bufflen, reconnect);
 719                 if (msg_byte(result) == DISCONNECT)
 720                         break;
 721                 SCtmp = SCint;
 722                 SCint = NULL;
 723                 SCtmp->result = result;
 724                 done_fn(SCtmp);
 725         }
 726         while (SCint);
 727         recursion_depth--;
 728         return 0;
 729 }
 730
 731 static int internal_command (unsigned char target, unsigned char lun,
 732                   const void *cmnd, void *buff, int bufflen, int reselect)
 733 {
 734         unsigned char *data = NULL;
 735         struct scatterlist *buffer = NULL;
 736         int clock, temp, nobuffs = 0, done = 0, len = 0;
 737 #if DEBUG
 738         int transfered = 0, phase = 0, newphase;
 739 #endif
 740         register unsigned char status_read;
 741         unsigned char tmp_data, tmp_control, status = 0, message = 0;
 742         unsigned transfersize = 0, underflow = 0;
 743 #ifdef SLOW_RATE
 744         int borken = (int) SCint->device->borken;       /* Does the current target require
 745                                                            Very Slow I/O ?  */
 746 #endif
 747
 748         incommand = 0;
 749         st0x_aborted = 0;
 750
 751 #if (DEBUG & PRINT_COMMAND)
 752         printk("scsi%d : target = %d, command = ", hostno, target);
 753         __scsi_print_command((unsigned char *) cmnd);
 754 #endif
 755
 756 #if (DEBUG & PHASE_RESELECT)
 757         switch (reselect) {
 758         case RECONNECT_NOW:
 759                 printk("scsi%d : reconnecting\n", hostno);
 760                 break;
 761 #ifdef LINKED
 762         case LINKED_RIGHT:
 763                 printk("scsi%d : connected, can reconnect\n", hostno);
 764                 break;
 765         case LINKED_WRONG:
 766                 printk("scsi%d : connected to wrong target, can reconnect\n",
 767                         hostno);
 768                 break;
 769 #endif
 770         case CAN_RECONNECT:
 771                 printk("scsi%d : allowed to reconnect\n", hostno);
 772                 break;
 773         default:
 774                 printk("scsi%d : not allowed to reconnect\n", hostno);
 775         }
 776 #endif
 777
 778         if (target == (controller_type == SEAGATE ? 7 : 6))
 779                 return DID_BAD_TARGET;
 780
 781         /*
 782          *      We work it differently depending on if this is is "the first time,"
 783          *      or a reconnect.  If this is a reselect phase, then SEL will
 784          *      be asserted, and we must skip selection / arbitration phases.
 785          */
 786
 787         switch (reselect) {
 788         case RECONNECT_NOW:
 789                 DPRINTK (PHASE_RESELECT, "scsi%d : phase RESELECT \n", hostno);
 790                 /*
 791                  *      At this point, we should find the logical or of our ID
 792                  *      and the original target's ID on the BUS, with BSY, SEL,
 793                  *      and I/O signals asserted.
 794                  *
 795                  *      After ARBITRATION phase is completed, only SEL, BSY,
 796                  *      and the target ID are asserted.  A valid initiator ID
 797                  *      is not on the bus until IO is asserted, so we must wait
 798                  *      for that.
 799                  */
 800                 ULOOP (100 * 1000) {
 801                         temp = STATUS;
 802                         if ((temp & STAT_IO) && !(temp & STAT_BSY))
 803                                 break;
 804                         if (TIMEOUT) {
 805                                 DPRINTK (PHASE_RESELECT, "scsi%d : RESELECT timed out while waiting for IO .\n", hostno);
 806                                 return (DID_BAD_INTR << 16);
 807                         }
 808                 }
 809
 810                 /*
 811                  *      After I/O is asserted by the target, we can read our ID
 812                  *      and its ID off of the BUS.
 813                  */
 814
 815                 if (!((temp = DATA) & (controller_type == SEAGATE ? 0x80 : 0x40))) {
 816                         DPRINTK (PHASE_RESELECT, "scsi%d : detected reconnect request to different target.\n\tData bus = %d\n", hostno, temp);
 817                         return (DID_BAD_INTR << 16);
 818                 }
 819
 820                 if (!(temp & (1 << current_target))) {
 821                         printk(KERN_WARNING "scsi%d : Unexpected reselect interrupt.  Data bus = %d\n", hostno, temp);
 822                         return (DID_BAD_INTR << 16);
 823                 }
 824
 825                 buffer = current_buffer;
 826                 cmnd = current_cmnd;    /* WDE add */
 827                 data = current_data;    /* WDE add */
 828                 len = current_bufflen;  /* WDE add */
 829                 nobuffs = current_nobuffs;
 830
 831                 /*
 832                  *      We have determined that we have been selected.  At this
 833                  *      point, we must respond to the reselection by asserting
 834                  *      BSY ourselves
 835                  */
 836
 837 #if 1
 838                 WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE | CMD_BSY);
 839 #else
 840                 WRITE_CONTROL (BASE_CMD | CMD_BSY);
 841 #endif
 842
 843                 /*
 844                  *      The target will drop SEL, and raise BSY, at which time
 845                  *      we must drop BSY.
 846                  */
 847
 848                 ULOOP (100 * 1000) {
 849                         if (!(STATUS & STAT_SEL))
 850                                 break;
 851                         if (TIMEOUT) {
 852                                 WRITE_CONTROL (BASE_CMD | CMD_INTR);
 853                                 DPRINTK (PHASE_RESELECT, "scsi%d : RESELECT timed out while waiting for SEL.\n", hostno);
 854                                 return (DID_BAD_INTR << 16);
 855                         }
 856                 }
 857                 WRITE_CONTROL (BASE_CMD);
 858                 /*
 859                  *      At this point, we have connected with the target
 860                  *      and can get on with our lives.
 861                  */
 862                 break;
 863         case CAN_RECONNECT:
 864 #ifdef LINKED
 865                 /*
 866                  * This is a bletcherous hack, just as bad as the Unix #!
 867                  * interpreter stuff. If it turns out we are using the wrong
 868                  * I_T_L nexus, the easiest way to deal with it is to go into
 869                  *  our INFORMATION TRANSFER PHASE code, send a ABORT
 870                  * message on MESSAGE OUT phase, and then loop back to here.
 871                  */
 872 connect_loop:
 873 #endif
 874                 DPRINTK (PHASE_BUS_FREE, "scsi%d : phase = BUS FREE \n", hostno);
 875
 876                 /*
 877                  *    BUS FREE PHASE
 878                  *
 879                  *      On entry, we make sure that the BUS is in a BUS FREE
 880                  *      phase, by insuring that both BSY and SEL are low for
 881                  *      at least one bus settle delay.  Several reads help
 882                  *      eliminate wire glitch.
 883                  */
 884
 885 #ifndef ARBITRATE
 886 #error FIXME: this is broken: we may not use jiffies here - we are under cli(). It will hardlock.
 887                 clock = jiffies + ST0X_BUS_FREE_DELAY;
 888
 889                 while (((STATUS | STATUS | STATUS) & (STAT_BSY | STAT_SEL)) && (!st0x_aborted) && time_before (jiffies, clock))
 890                         cpu_relax();
 891
 892                 if (time_after (jiffies, clock))
 893                         return retcode (DID_BUS_BUSY);
 894                 else if (st0x_aborted)
 895                         return retcode (st0x_aborted);
 896 #endif
 897                 DPRINTK (PHASE_SELECTION, "scsi%d : phase = SELECTION\n", hostno);
 898
 899                 clock = jiffies + ST0X_SELECTION_DELAY;
 900
 901                 /*
 902                  * Arbitration/selection procedure :
 903                  * 1.  Disable drivers
 904                  * 2.  Write HOST adapter address bit
 905                  * 3.  Set start arbitration.
 906                  * 4.  We get either ARBITRATION COMPLETE or SELECT at this
 907                  *     point.
 908                  * 5.  OR our ID and targets on bus.
 909                  * 6.  Enable SCSI drivers and asserted SEL and ATTN
 910                  */
 911
 912 #ifdef ARBITRATE
 913                 /* FIXME: verify host lock is always held here */
 914                 WRITE_CONTROL(0);
 915                 WRITE_DATA((controller_type == SEAGATE) ? 0x80 : 0x40);
 916                 WRITE_CONTROL(CMD_START_ARB);
 917
 918                 ULOOP (ST0X_SELECTION_DELAY * 10000) {
 919                         status_read = STATUS;
 920                         if (status_read & STAT_ARB_CMPL)
 921                                 break;
 922                         if (st0x_aborted)       /* FIXME: What? We are going to do something even after abort? */
 923                                 break;
 924                         if (TIMEOUT || (status_read & STAT_SEL)) {
 925                                 printk(KERN_WARNING "scsi%d : arbitration lost or timeout.\n", hostno);
 926                                 WRITE_CONTROL (BASE_CMD);
 927                                 return retcode (DID_NO_CONNECT);
 928                         }
 929                 }
 930                 DPRINTK (PHASE_SELECTION, "scsi%d : arbitration complete\n", hostno);
 931 #endif
 932
 933                 /*
 934                  *    When the SCSI device decides that we're gawking at it,
 935                  *    it will respond by asserting BUSY on the bus.
 936                  *
 937                  *    Note : the Seagate ST-01/02 product manual says that we
 938                  *    should twiddle the DATA register before the control
 939                  *    register. However, this does not work reliably so we do
 940                  *    it the other way around.
 941                  *
 942                  *    Probably could be a problem with arbitration too, we
 943                  *    really should try this with a SCSI protocol or logic
 944                  *    analyzer to see what is going on.
 945                  */
 946                 tmp_data = (unsigned char) ((1 << target) | (controller_type == SEAGATE ? 0x80 : 0x40));
 947                 tmp_control = BASE_CMD | CMD_DRVR_ENABLE | CMD_SEL | (reselect ? CMD_ATTN : 0);
 948
 949                 /* FIXME: verify host lock is always held here */
 950 #ifdef OLDCNTDATASCEME
 951 #ifdef SWAPCNTDATA
 952                 WRITE_CONTROL (tmp_control);
 953                 WRITE_DATA (tmp_data);
 954 #else
 955                 WRITE_DATA (tmp_data);
 956                 WRITE_CONTROL (tmp_control);
 957 #endif
 958 #else
 959                 tmp_control ^= CMD_BSY; /* This is guesswork. What used to be in driver    */
 960                 WRITE_CONTROL (tmp_control);    /* could never work: it sent data into control     */
 961                 WRITE_DATA (tmp_data);  /* register and control info into data. Hopefully  */
 962                 tmp_control ^= CMD_BSY; /* fixed, but order of first two may be wrong.     */
 963                 WRITE_CONTROL (tmp_control);    /* -- pavel@ucw.cz   */
 964 #endif
 965
 966                 ULOOP (250 * 1000) {
 967                         if (st0x_aborted) {
 968                                 /*
 969                                  *      If we have been aborted, and we have a
 970                                  *      command in progress, IE the target
 971                                  *      still has BSY asserted, then we will
 972                                  *      reset the bus, and notify the midlevel
 973                                  *      driver to expect sense.
 974                                  */
 975
 976                                 WRITE_CONTROL (BASE_CMD);
 977                                 if (STATUS & STAT_BSY) {
 978                                         printk(KERN_WARNING "scsi%d : BST asserted after we've been aborted.\n", hostno);
 979                                         seagate_st0x_bus_reset(NULL);
 980                                         return retcode (DID_RESET);
 981                                 }
 982                                 return retcode (st0x_aborted);
 983                         }
 984                         if (STATUS & STAT_BSY)
 985                                 break;
 986                         if (TIMEOUT) {
 987                                 DPRINTK (PHASE_SELECTION, "scsi%d : NO CONNECT with target %d, stat = %x \n", hostno, target, STATUS);
 988                                 return retcode (DID_NO_CONNECT);
 989                         }
 990                 }
 991
 992                 /* Establish current pointers.  Take into account scatter / gather */
 993
 994                 if ((nobuffs = SCint->use_sg)) {
 995 #if (DEBUG & DEBUG_SG)
 996                         {
 997                                 int i;
 998                                 printk("scsi%d : scatter gather requested, using %d buffers.\n", hostno, nobuffs);
 999                                 for (i = 0; i < nobuffs; ++i)
1000                                         printk("scsi%d : buffer %d address = %p length = %d\n",
1001                                              hostno, i,
1002                                              page_address(buffer[i].page) + buffer[i].offset,
1003                                              buffer[i].length);
1004                         }
1005 #endif
1006
1007                         buffer = (struct scatterlist *) SCint->request_buffer;
1008                         len = buffer->length;
1009                         data = page_address(buffer->page) + buffer->offset;
1010                 } else {
1011                         DPRINTK (DEBUG_SG, "scsi%d : scatter gather not requested.\n", hostno);
1012                         buffer = NULL;
1013                         len = SCint->request_bufflen;
1014                         data = (unsigned char *) SCint->request_buffer;
1015                 }
1016
1017                 DPRINTK (PHASE_DATAIN | PHASE_DATAOUT, "scsi%d : len = %d\n",
1018                          hostno, len);
1019
1020                 break;
1021 #ifdef LINKED
1022         case LINKED_RIGHT:
1023                 break;
1024         case LINKED_WRONG:
1025                 break;
1026 #endif
1027         }                       /* end of switch(reselect) */
1028
1029         /*
1030          *    There are several conditions under which we wish to send a message :
1031          *      1.  When we are allowing disconnect / reconnect, and need to
1032          *      establish the I_T_L nexus via an IDENTIFY with the DiscPriv bit
1033          *      set.
1034          *
1035          *      2.  When we are doing linked commands, are have the wrong I_T_L
1036          *      nexus established and want to send an ABORT message.
1037          */
1038
1039         /* GCC does not like an ifdef inside a macro, so do it the hard way. */
1040 #ifdef LINKED
1041         WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE | (((reselect == CAN_RECONNECT)|| (reselect == LINKED_WRONG))? CMD_ATTN : 0));
1042 #else
1043         WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE | (((reselect == CAN_RECONNECT))? CMD_ATTN : 0));
1044 #endif
1045
1046         /*
1047          *    INFORMATION TRANSFER PHASE
1048          *
1049          *      The nasty looking read / write inline assembler loops we use for
1050          *      DATAIN and DATAOUT phases are approximately 4-5 times as fast as
1051          *      the 'C' versions - since we're moving 1024 bytes of data, this
1052          *      really adds up.
1053          *
1054          *      SJT: The nasty-looking assembler is gone, so it's slower.
1055          *
1056          */
1057
1058         DPRINTK (PHASE_ETC, "scsi%d : phase = INFORMATION TRANSFER\n", hostno);
1059
1060         incommand = 1;
1061         transfersize = SCint->transfersize;
1062         underflow = SCint->underflow;
1063
1064         /*
1065          *      Now, we poll the device for status information,
1066          *      and handle any requests it makes.  Note that since we are unsure
1067          *      of how much data will be flowing across the system, etc and
1068          *      cannot make reasonable timeouts, that we will instead have the
1069          *      midlevel driver handle any timeouts that occur in this phase.
1070          */
1071
1072         while (((status_read = STATUS) & STAT_BSY) && !st0x_aborted && !done) {
1073 #ifdef PARITY
1074                 if (status_read & STAT_PARITY) {
1075                         printk(KERN_ERR "scsi%d : got parity error\n", hostno);
1076                         st0x_aborted = DID_PARITY;
1077                 }
1078 #endif
1079                 if (status_read & STAT_REQ) {
1080 #if ((DEBUG & PHASE_ETC) == PHASE_ETC)
1081                         if ((newphase = (status_read & REQ_MASK)) != phase) {
1082                                 phase = newphase;
1083                                 switch (phase) {
1084                                 case REQ_DATAOUT:
1085                                         printk ("scsi%d : phase = DATA OUT\n", hostno);
1086                                         break;
1087                                 case REQ_DATAIN:
1088                                         printk ("scsi%d : phase = DATA IN\n", hostno);
1089                                         break;
1090                                 case REQ_CMDOUT:
1091                                         printk
1092                                             ("scsi%d : phase = COMMAND OUT\n", hostno);
1093                                         break;
1094                                 case REQ_STATIN:
1095                                         printk ("scsi%d : phase = STATUS IN\n", hostno);
1096                                         break;
1097                                 case REQ_MSGOUT:
1098                                         printk
1099                                             ("scsi%d : phase = MESSAGE OUT\n", hostno);
1100                                         break;
1101                                 case REQ_MSGIN:
1102                                         printk ("scsi%d : phase = MESSAGE IN\n", hostno);
1103                                         break;
1104                                 default:
1105                                         printk ("scsi%d : phase = UNKNOWN\n", hostno);
1106                                         st0x_aborted = DID_ERROR;
1107                                 }
1108                         }
1109 #endif
1110                         switch (status_read & REQ_MASK) {
1111                         case REQ_DATAOUT:
1112                                 /*
1113                                  * If we are in fast mode, then we simply splat
1114                                  * the data out in word-sized chunks as fast as
1115                                  * we can.
1116                                  */
1117
1118                                 if (!len) {
1119 #if 0
1120                                         printk("scsi%d: underflow to target %d lun %d \n", hostno, target, lun);
1121                                         st0x_aborted = DID_ERROR;
1122                                         fast = 0;
1123 #endif
1124                                         break;
1125                                 }
1126
1127                                 if (fast && transfersize
1128                                     && !(len % transfersize)
1129                                     && (len >= transfersize)
1130 #ifdef FAST32
1131                                     && !(transfersize % 4)
1132 #endif
1133                                     ) {
1134                                         DPRINTK (DEBUG_FAST,
1135                                                  "scsi%d : FAST transfer, underflow = %d, transfersize = %d\n"
1136                                                  "         len = %d, data = %08x\n",
1137                                                  hostno, SCint->underflow,
1138                                                  SCint->transfersize, len,
1139                                                  data);
1140
1141                         /* SJT: Start. Fast Write */
1142 #ifdef SEAGATE_USE_ASM
1143                                         __asm__ ("cld\n\t"
1144 #ifdef FAST32
1145                                                  "shr $2, %%ecx\n\t"
1146                                                  "1:\t"
1147                                                  "lodsl\n\t"
1148                                                  "movl %%eax, (%%edi)\n\t"
1149 #else
1150                                                  "1:\t"
1151                                                  "lodsb\n\t"
1152                                                  "movb %%al, (%%edi)\n\t"
1153 #endif
1154                                                  "loop 1b;"
1155                                       /* output */ :
1156                                       /* input */ :"D" (st0x_dr),
1157                                                  "S"
1158                                                  (data),
1159                                                  "c" (SCint->transfersize)
1160 /* clobbered */
1161                                       :  "eax", "ecx",
1162                                                  "esi");
1163 #else                           /* SEAGATE_USE_ASM */
1164                                         memcpy_toio(st0x_dr, data, transfersize);
1165 #endif                          /* SEAGATE_USE_ASM */
1166 /* SJT: End */
1167                                         len -= transfersize;
1168                                         data += transfersize;
1169                                         DPRINTK (DEBUG_FAST, "scsi%d : FAST transfer complete len = %d data = %08x\n", hostno, len, data);
1170                                 } else {
1171                                         /*
1172                                          *    We loop as long as we are in a
1173                                          *    data out phase, there is data to
1174                                          *    send, and BSY is still active.
1175                                          */
1176
1177 /* SJT: Start. Slow Write. */
1178 #ifdef SEAGATE_USE_ASM
1179
1180                                         int __dummy_1, __dummy_2;
1181
1182 /*
1183  *      We loop as long as we are in a data out phase, there is data to send,
1184  *      and BSY is still active.
1185  */
1186 /* Local variables : len = ecx , data = esi,
1187                      st0x_cr_sr = ebx, st0x_dr =  edi
1188 */
1189                                         __asm__ (
1190                                                         /* Test for any data here at all. */
1191                                                         "orl %%ecx, %%ecx\n\t"
1192                                                         "jz 2f\n\t" "cld\n\t"
1193 /*                    "movl st0x_cr_sr, %%ebx\n\t"  */
1194 /*                    "movl st0x_dr, %%edi\n\t"  */
1195                                                         "1:\t"
1196                                                         "movb (%%ebx), %%al\n\t"
1197                                                         /* Test for BSY */
1198                                                         "test $1, %%al\n\t"
1199                                                         "jz 2f\n\t"
1200                                                         /* Test for data out phase - STATUS & REQ_MASK should be
1201                                                            REQ_DATAOUT, which is 0. */
1202                                                         "test $0xe, %%al\n\t"
1203                                                         "jnz 2f\n\t"
1204                                                         /* Test for REQ */
1205                                                         "test $0x10, %%al\n\t"
1206                                                         "jz 1b\n\t"
1207                                                         "lodsb\n\t"
1208                                                         "movb %%al, (%%edi)\n\t"
1209                                                         "loop 1b\n\t" "2:\n"
1210                                       /* output */ :"=S" (data), "=c" (len),
1211                                                         "=b"
1212                                                         (__dummy_1),
1213                                                         "=D" (__dummy_2)
1214 /* input */
1215                                       :         "0" (data), "1" (len),
1216                                                         "2" (st0x_cr_sr),
1217                                                         "3" (st0x_dr)
1218 /* clobbered */
1219                                       :         "eax");
1220 #else                           /* SEAGATE_USE_ASM */
1221                                         while (len) {
1222                                                 unsigned char stat;
1223
1224                                                 stat = STATUS;
1225                                                 if (!(stat & STAT_BSY)
1226                                                     || ((stat & REQ_MASK) !=
1227                                                         REQ_DATAOUT))
1228                                                         break;
1229                                                 if (stat & STAT_REQ) {
1230                                                         WRITE_DATA (*data++);
1231                                                         --len;
1232                                                 }
1233                                         }
1234 #endif                          /* SEAGATE_USE_ASM */
1235 /* SJT: End. */
1236                                 }
1237
1238                                 if (!len && nobuffs) {
1239                                         --nobuffs;
1240                                         ++buffer;
1241                                         len = buffer->length;
1242                                         data = page_address(buffer->page) + buffer->offset;
1243                                         DPRINTK (DEBUG_SG,
1244                                                  "scsi%d : next scatter-gather buffer len = %d address = %08x\n",
1245                                                  hostno, len, data);
1246                                 }
1247                                 break;
1248
1249                         case REQ_DATAIN:
1250 #ifdef SLOW_RATE
1251                                 if (borken) {
1252 #if (DEBUG & (PHASE_DATAIN))
1253                                         transfered += len;
1254 #endif
1255                                         for (; len && (STATUS & (REQ_MASK | STAT_REQ)) == (REQ_DATAIN | STAT_REQ); --len) {
1256                                                 *data++ = DATA;
1257                                                 borken_wait();
1258                                         }
1259 #if (DEBUG & (PHASE_DATAIN))
1260                                         transfered -= len;
1261 #endif
1262                                 } else
1263 #endif
1264
1265                                         if (fast && transfersize
1266                                             && !(len % transfersize)
1267                                             && (len >= transfersize)
1268 #ifdef FAST32
1269                                             && !(transfersize % 4)
1270 #endif
1271                                     ) {
1272                                         DPRINTK (DEBUG_FAST,
1273                                                  "scsi%d : FAST transfer, underflow = %d, transfersize = %d\n"
1274                                                  "         len = %d, data = %08x\n",
1275                                                  hostno, SCint->underflow,
1276                                                  SCint->transfersize, len,
1277                                                  data);
1278
1279 /* SJT: Start. Fast Read */
1280 #ifdef SEAGATE_USE_ASM
1281                                         __asm__ ("cld\n\t"
1282 #ifdef FAST32
1283                                                  "shr $2, %%ecx\n\t"
1284                                                  "1:\t"
1285                                                  "movl (%%esi), %%eax\n\t"
1286                                                  "stosl\n\t"
1287 #else
1288                                                  "1:\t"
1289                                                  "movb (%%esi), %%al\n\t"
1290                                                  "stosb\n\t"
1291 #endif
1292                                                  "loop 1b\n\t"
1293                                       /* output */ :
1294                                       /* input */ :"S" (st0x_dr),
1295                                                  "D"
1296                                                  (data),
1297                                                  "c" (SCint->transfersize)
1298 /* clobbered */
1299                                       :  "eax", "ecx",
1300                                                  "edi");
1301 #else                           /* SEAGATE_USE_ASM */
1302                                         memcpy_fromio(data, st0x_dr, len);
1303 #endif                          /* SEAGATE_USE_ASM */
1304 /* SJT: End */
1305                                         len -= transfersize;
1306                                         data += transfersize;
1307 #if (DEBUG & PHASE_DATAIN)
1308                                         printk ("scsi%d: transfered += %d\n", hostno, transfersize);
1309                                         transfered += transfersize;
1310 #endif
1311
1312                                         DPRINTK (DEBUG_FAST, "scsi%d : FAST transfer complete len = %d data = %08x\n", hostno, len, data);
1313                                 } else {
1314
1315 #if (DEBUG & PHASE_DATAIN)
1316                                         printk ("scsi%d: transfered += %d\n", hostno, len);
1317                                         transfered += len;      /* Assume we'll transfer it all, then
1318                                                                    subtract what we *didn't* transfer */
1319 #endif
1320
1321 /*
1322  *      We loop as long as we are in a data in phase, there is room to read,
1323  *      and BSY is still active
1324  */
1325
1326 /* SJT: Start. */
1327 #ifdef SEAGATE_USE_ASM
1328
1329                                         int __dummy_3, __dummy_4;
1330
1331 /* Dummy clobbering variables for the new gcc-2.95 */
1332
1333 /*
1334  *      We loop as long as we are in a data in phase, there is room to read,
1335  *      and BSY is still active
1336  */
1337                                         /* Local variables : ecx = len, edi = data
1338                                            esi = st0x_cr_sr, ebx = st0x_dr */
1339                                         __asm__ (
1340                                                         /* Test for room to read */
1341                                                         "orl %%ecx, %%ecx\n\t"
1342                                                         "jz 2f\n\t" "cld\n\t"
1343 /*                "movl st0x_cr_sr, %%esi\n\t"  */
1344 /*                "movl st0x_dr, %%ebx\n\t"  */
1345                                                         "1:\t"
1346                                                         "movb (%%esi), %%al\n\t"
1347                                                         /* Test for BSY */
1348                                                         "test $1, %%al\n\t"
1349                                                         "jz 2f\n\t"
1350                                                         /* Test for data in phase - STATUS & REQ_MASK should be REQ_DATAIN,
1351                                                            = STAT_IO, which is 4. */
1352                                                         "movb $0xe, %%ah\n\t"
1353                                                         "andb %%al, %%ah\n\t"
1354                                                         "cmpb $0x04, %%ah\n\t"
1355                                                         "jne 2f\n\t"
1356                                                         /* Test for REQ */
1357                                                         "test $0x10, %%al\n\t"
1358                                                         "jz 1b\n\t"
1359                                                         "movb (%%ebx), %%al\n\t"
1360                                                         "stosb\n\t"
1361                                                         "loop 1b\n\t" "2:\n"
1362                                       /* output */ :"=D" (data), "=c" (len),
1363                                                         "=S"
1364                                                         (__dummy_3),
1365                                                         "=b" (__dummy_4)
1366 /* input */
1367                                       :         "0" (data), "1" (len),
1368                                                         "2" (st0x_cr_sr),
1369                                                         "3" (st0x_dr)
1370 /* clobbered */
1371                                       :         "eax");
1372 #else                           /* SEAGATE_USE_ASM */
1373                                         while (len) {
1374                                                 unsigned char stat;
1375
1376                                                 stat = STATUS;
1377                                                 if (!(stat & STAT_BSY)
1378                                                     || ((stat & REQ_MASK) !=
1379                                                         REQ_DATAIN))
1380                                                         break;
1381                                                 if (stat & STAT_REQ) {
1382                                                         *data++ = DATA;
1383                                                         --len;
1384                                                 }
1385                                         }
1386 #endif                          /* SEAGATE_USE_ASM */
1387 /* SJT: End. */
1388 #if (DEBUG & PHASE_DATAIN)
1389                                         printk ("scsi%d: transfered -= %d\n", hostno, len);
1390                                         transfered -= len;      /* Since we assumed all of Len got  *
1391                                                                    transfered, correct our mistake */
1392 #endif
1393                                 }
1394
1395                                 if (!len && nobuffs) {
1396                                         --nobuffs;
1397                                         ++buffer;
1398                                         len = buffer->length;
1399                                         data = page_address(buffer->page) + buffer->offset;
1400                                         DPRINTK (DEBUG_SG, "scsi%d : next scatter-gather buffer len = %d address = %08x\n", hostno, len, data);
1401                                 }
1402                                 break;
1403
1404                         case REQ_CMDOUT:
1405                                 while (((status_read = STATUS) & STAT_BSY) &&
1406                                        ((status_read & REQ_MASK) == REQ_CMDOUT))
1407                                         if (status_read & STAT_REQ) {
1408                                                 WRITE_DATA (*(const unsigned char *) cmnd);
1409                                                 cmnd = 1 + (const unsigned char *)cmnd;
1410 #ifdef SLOW_RATE
1411                                                 if (borken)
1412                                                         borken_wait ();
1413 #endif
1414                                         }
1415                                 break;
1416
1417                         case REQ_STATIN:
1418                                 status = DATA;
1419                                 break;
1420
1421                         case REQ_MSGOUT:
1422                                 /*
1423                                  *      We can only have sent a MSG OUT if we
1424                                  *      requested to do this by raising ATTN.
1425                                  *      So, we must drop ATTN.
1426                                  */
1427                                 WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE);
1428                                 /*
1429                                  *      If we are reconnecting, then we must
1430                                  *      send an IDENTIFY message in response
1431                                  *      to MSGOUT.
1432                                  */
1433                                 switch (reselect) {
1434                                 case CAN_RECONNECT:
1435                                         WRITE_DATA (IDENTIFY (1, lun));
1436                                         DPRINTK (PHASE_RESELECT | PHASE_MSGOUT, "scsi%d : sent IDENTIFY message.\n", hostno);
1437                                         break;
1438 #ifdef LINKED
1439                                 case LINKED_WRONG:
1440                                         WRITE_DATA (ABORT);
1441                                         linked_connected = 0;
1442                                         reselect = CAN_RECONNECT;
1443                                         goto connect_loop;
1444                                         DPRINTK (PHASE_MSGOUT | DEBUG_LINKED, "scsi%d : sent ABORT message to cancel incorrect I_T_L nexus.\n", hostno);
1445 #endif                                  /* LINKED */
1446                                         DPRINTK (DEBUG_LINKED, "correct\n");
1447                                 default:
1448                                         WRITE_DATA (NOP);
1449                                         printk("scsi%d : target %d requested MSGOUT, sent NOP message.\n", hostno, target);
1450                                 }
1451                                 break;
1452
1453                         case REQ_MSGIN:
1454                                 switch (message = DATA) {
1455                                 case DISCONNECT:
1456                                         DANY("seagate: deciding to disconnect\n");
1457                                         should_reconnect = 1;
1458                                         current_data = data;    /* WDE add */
1459                                         current_buffer = buffer;
1460                                         current_bufflen = len;  /* WDE add */
1461                                         current_nobuffs = nobuffs;
1462 #ifdef LINKED
1463                                         linked_connected = 0;
1464 #endif
1465                                         done = 1;
1466                                         DPRINTK ((PHASE_RESELECT | PHASE_MSGIN), "scsi%d : disconnected.\n", hostno);
1467                                         break;
1468
1469 #ifdef LINKED
1470                                 case LINKED_CMD_COMPLETE:
1471                                 case LINKED_FLG_CMD_COMPLETE:
1472 #endif
1473                                 case COMMAND_COMPLETE:
1474                                         /*
1475                                          * Note : we should check for underflow here.
1476                                          */
1477                                         DPRINTK(PHASE_MSGIN, "scsi%d : command complete.\n", hostno);
1478                                         done = 1;
1479                                         break;
1480                                 case ABORT:
1481                                         DPRINTK(PHASE_MSGIN, "scsi%d : abort message.\n", hostno);
1482                                         done = 1;
1483                                         break;
1484                                 case SAVE_POINTERS:
1485                                         current_buffer = buffer;
1486                                         current_bufflen = len;  /* WDE add */
1487                                         current_data = data;    /* WDE mod */
1488                                         current_nobuffs = nobuffs;
1489                                         DPRINTK (PHASE_MSGIN, "scsi%d : pointers saved.\n", hostno);
1490                                         break;
1491                                 case RESTORE_POINTERS:
1492                                         buffer = current_buffer;
1493                                         cmnd = current_cmnd;
1494                                         data = current_data;    /* WDE mod */
1495                                         len = current_bufflen;
1496                                         nobuffs = current_nobuffs;
1497                                         DPRINTK(PHASE_MSGIN, "scsi%d : pointers restored.\n", hostno);
1498                                         break;
1499                                 default:
1500
1501                                         /*
1502                                          *      IDENTIFY distinguishes itself
1503                                          *      from the other messages by
1504                                          *      setting the high bit.
1505                                          *
1506                                          *      Note : we need to handle at
1507                                          *      least one outstanding command
1508                                          *      per LUN, and need to hash the
1509                                          *      SCSI command for that I_T_L
1510                                          *      nexus based on the known ID
1511                                          *      (at this point) and LUN.
1512                                          */
1513
1514                                         if (message & 0x80) {
1515                                                 DPRINTK (PHASE_MSGIN, "scsi%d : IDENTIFY message received from id %d, lun %d.\n", hostno, target, message & 7);
1516                                         } else {
1517                                                 /*
1518                                                  *      We should go into a
1519                                                  *      MESSAGE OUT phase, and
1520                                                  *      send  a MESSAGE_REJECT
1521                                                  *      if we run into a message
1522                                                  *      that we don't like.  The
1523                                                  *      seagate driver needs
1524                                                  *      some serious
1525                                                  *      restructuring first
1526                                                  *      though.
1527                                                  */
1528                                                 DPRINTK (PHASE_MSGIN, "scsi%d : unknown message %d from target %d.\n", hostno, message, target);
1529                                         }
1530                                 }
1531                                 break;
1532                         default:
1533                                 printk(KERN_ERR "scsi%d : unknown phase.\n", hostno);
1534                                 st0x_aborted = DID_ERROR;
1535                         }       /* end of switch (status_read &  REQ_MASK) */
1536 #ifdef SLOW_RATE
1537                         /*
1538                          * I really don't care to deal with borken devices in
1539                          * each single byte transfer case (ie, message in,
1540                          * message out, status), so I'll do the wait here if
1541                          * necessary.
1542                          */
1543                         if(borken)
1544                                 borken_wait();
1545 #endif
1546
1547                 }               /* if(status_read & STAT_REQ) ends */
1548         }                       /* while(((status_read = STATUS)...) ends */
1549
1550         DPRINTK(PHASE_DATAIN | PHASE_DATAOUT | PHASE_EXIT, "scsi%d : Transfered %d bytes\n", hostno, transfered);
1551
1552 #if (DEBUG & PHASE_EXIT)
1553 #if 0                           /* Doesn't work for scatter/gather */
1554         printk("Buffer : \n");
1555         for(i = 0; i < 20; ++i)
1556                 printk("%02x  ", ((unsigned char *) data)[i]);  /* WDE mod */
1557         printk("\n");
1558 #endif
1559         printk("scsi%d : status = ", hostno);
1560         scsi_print_status(status);
1561         printk(" message = %02x\n", message);
1562 #endif
1563
1564         /* We shouldn't reach this until *after* BSY has been deasserted */
1565
1566 #ifdef LINKED
1567         else
1568         {
1569                 /*
1570                  * Fix the message byte so that unsuspecting high level drivers
1571                  * don't puke when they see a LINKED COMMAND message in place of
1572                  * the COMMAND COMPLETE they may be expecting.  Shouldn't be
1573                  * necessary, but it's better to be on the safe side.
1574                  *
1575                  * A non LINKED* message byte will indicate that the command
1576                  * completed, and we are now disconnected.
1577                  */
1578
1579                 switch (message) {
1580                 case LINKED_CMD_COMPLETE:
1581                 case LINKED_FLG_CMD_COMPLETE:
1582                         message = COMMAND_COMPLETE;
1583                         linked_target = current_target;
1584                         linked_lun = current_lun;
1585                         linked_connected = 1;
1586                         DPRINTK (DEBUG_LINKED, "scsi%d : keeping I_T_L nexus established for linked command.\n", hostno);
1587                         /* We also will need to adjust status to accommodate intermediate
1588                            conditions. */
1589                         if ((status == INTERMEDIATE_GOOD) || (status == INTERMEDIATE_C_GOOD))
1590                                 status = GOOD;
1591                         break;
1592                         /*
1593                          * We should also handle what are "normal" termination
1594                          * messages here (ABORT, BUS_DEVICE_RESET?, and
1595                          * COMMAND_COMPLETE individually, and flake if things
1596                          * aren't right.
1597                          */
1598                 default:
1599                         DPRINTK (DEBUG_LINKED, "scsi%d : closing I_T_L nexus.\n", hostno);
1600                         linked_connected = 0;
1601                 }
1602         }
1603 #endif  /* LINKED */
1604
1605         if (should_reconnect) {
1606                 DPRINTK (PHASE_RESELECT, "scsi%d : exiting seagate_st0x_queue_command() with reconnect enabled.\n", hostno);
1607                 WRITE_CONTROL (BASE_CMD | CMD_INTR);
1608         } else
1609                 WRITE_CONTROL (BASE_CMD);
1610
1611         return retcode (st0x_aborted);
1612 }                               /* end of internal_command */
1613
1614 static int seagate_st0x_abort(struct scsi_cmnd * SCpnt)
1615 {
1616         st0x_aborted = DID_ABORT;
1617         return SUCCESS;
1618 }
1619
1620 #undef ULOOP
1621 #undef TIMEOUT
1622
1623 /*
1624  * the seagate_st0x_reset function resets the SCSI bus
1625  *
1626  * May be called with SCpnt = NULL
1627  */
1628
1629 static int seagate_st0x_bus_reset(struct scsi_cmnd * SCpnt)
1630 {
1631         /* No timeouts - this command is going to fail because it was reset. */
1632         DANY ("scsi%d: Reseting bus... ", hostno);
1633
1634         /* assert  RESET signal on SCSI bus.  */
1635         WRITE_CONTROL (BASE_CMD | CMD_RST);
1636
1637         mdelay (20);
1638
1639         WRITE_CONTROL (BASE_CMD);
1640         st0x_aborted = DID_RESET;
1641
1642         DANY ("done.\n");
1643         return SUCCESS;
1644 }
1645
1646 static int seagate_st0x_release(struct Scsi_Host *shost)
1647 {
1648         if (shost->irq)
1649                 free_irq(shost->irq, shost);
1650         release_region(shost->io_port, shost->n_io_port);
1651         return 0;
1652 }
1653
1654 static struct scsi_host_template driver_template = {
1655         .detect                 = seagate_st0x_detect,
1656         .release                = seagate_st0x_release,
1657         .info                   = seagate_st0x_info,
1658         .queuecommand           = seagate_st0x_queue_command,
1659         .eh_abort_handler       = seagate_st0x_abort,
1660         .eh_bus_reset_handler   = seagate_st0x_bus_reset,
1661         .can_queue              = 1,
1662         .this_id                = 7,
1663         .sg_tablesize           = SG_ALL,
1664         .cmd_per_lun            = 1,
1665         .use_clustering         = DISABLE_CLUSTERING,
1666 };
1667 #include "scsi_module.c"