drivers/ide/legacy/pdc4030.c

   1 /*  -*- linux-c -*-
   2  *  linux/drivers/ide/legacy/pdc4030.c          Version 0.90  May 27, 1999
   3  *
   4  *  Copyright (C) 1995-2002  Linus Torvalds & authors (see below)
   5  */
   6
   7 /*
   8  *  Principal Author/Maintainer:  Peter Denison <promise@pnd-pc.demon.co.uk>
   9  *
  10  *  This file provides support for the second port and cache of Promise
  11  *  IDE interfaces, e.g. DC4030VL, DC4030VL-1 and DC4030VL-2.
  12  *
  13  *  Thanks are due to Mark Lord for advice and patiently answering stupid
  14  *  questions, and all those mugs^H^H^H^Hbrave souls who've tested this,
  15  *  especially Andre Hedrick.
  16  *
  17  *  Version 0.01        Initial version, #include'd in ide.c rather than
  18  *                      compiled separately.
  19  *                      Reads use Promise commands, writes as before. Drives
  20  *                      on second channel are read-only.
  21  *  Version 0.02        Writes working on second channel, reads on both
  22  *                      channels. Writes fail under high load. Suspect
  23  *                      transfers of >127 sectors don't work.
  24  *  Version 0.03        Brought into line with ide.c version 5.27.
  25  *                      Other minor changes.
  26  *  Version 0.04        Updated for ide.c version 5.30
  27  *                      Changed initialization strategy
  28  *  Version 0.05        Kernel integration.  -ml
  29  *  Version 0.06        Ooops. Add hwgroup to direct call of ide_intr() -ml
  30  *  Version 0.07        Added support for DC4030 variants
  31  *                      Secondary interface autodetection
  32  *  Version 0.08        Renamed to pdc4030.c
  33  *  Version 0.09        Obsolete - never released - did manual write request
  34  *                      splitting before max_sectors[major][minor] available.
  35  *  Version 0.10        Updated for 2.1 series of kernels
  36  *  Version 0.11        Updated for 2.3 series of kernels
  37  *                      Autodetection code added.
  38  *
  39  *  Version 0.90        Transition to BETA code. No lost/unexpected interrupts
  40  */
  41
  42 /*
  43  * Once you've compiled it in, you'll have to also enable the interface
  44  * setup routine from the kernel command line, as in
  45  *
  46  *      'linux ide0=dc4030' or 'linux ide1=dc4030'
  47  *
  48  * It should now work as a second controller also ('ide1=dc4030') but only
  49  * if you DON'T have BIOS V4.44, which has a bug. If you have this version
  50  * and EPROM programming facilities, you need to fix 4 bytes:
  51  *      2496:   81      81
  52  *      2497:   3E      3E
  53  *      2498:   22      98      *
  54  *      2499:   06      05      *
  55  *      249A:   F0      F0
  56  *      249B:   01      01
  57  *      ...
  58  *      24A7:   81      81
  59  *      24A8:   3E      3E
  60  *      24A9:   22      98      *
  61  *      24AA:   06      05      *
  62  *      24AB:   70      70
  63  *      24AC:   01      01
  64  *
  65  * As of January 1999, Promise Technology Inc. have finally supplied me with
  66  * some technical information which has shed a glimmer of light on some of the
  67  * problems I was having, especially with writes.
  68  *
  69  * There are still potential problems with the robustness and efficiency of
  70  * this driver because I still don't understand what the card is doing with
  71  * interrupts, however, it has been stable for a while with no reports of ill
  72  * effects.
  73  */
  74
  75 #define DEBUG_READ
  76 #define DEBUG_WRITE
  77 #define __PROMISE_4030
  78
  79 #include <linux/module.h>
  80 #include <linux/config.h>
  81 #include <linux/types.h>
  82 #include <linux/kernel.h>
  83 #include <linux/delay.h>
  84 #include <linux/timer.h>
  85 #include <linux/mm.h>
  86 #include <linux/ioport.h>
  87 #include <linux/blkdev.h>
  88 #include <linux/hdreg.h>
  89 #include <linux/ide.h>
  90 #include <linux/init.h>
  91
  92 #include <asm/io.h>
  93 #include <asm/irq.h>
  94
  95 #include "pdc4030.h"
  96
  97 static ide_startstop_t promise_rw_disk (ide_drive_t *drive, struct request *rq, sector_t block);
  98
  99 /*
 100  * promise_selectproc() is invoked by ide.c
 101  * in preparation for access to the specified drive.
 102  */
 103 static void promise_selectproc (ide_drive_t *drive)
 104 {
 105         unsigned int number;
 106
 107         number = (HWIF(drive)->channel << 1) + drive->select.b.unit;
 108         HWIF(drive)->OUTB(number, IDE_FEATURE_REG);
 109 }
 110
 111 /*
 112  * pdc4030_cmd handles the set of vendor specific commands that are initiated
 113  * by command F0. They all have the same success/failure notification -
 114  * 'P' (=0x50) on success, 'p' (=0x70) on failure.
 115  */
 116 int pdc4030_cmd(ide_drive_t *drive, u8 cmd)
 117 {
 118         unsigned long timeout;
 119         u8 status_val;
 120
 121         promise_selectproc(drive);      /* redundant? */
 122         HWIF(drive)->OUTB(0xF3, IDE_SECTOR_REG);
 123         HWIF(drive)->OUTB(cmd, IDE_SELECT_REG);
 124         HWIF(drive)->OUTB(PROMISE_EXTENDED_COMMAND, IDE_COMMAND_REG);
 125         timeout = HZ * 10;
 126         timeout += jiffies;
 127         do {
 128                 if(time_after(jiffies, timeout)) {
 129                         return 2; /* device timed out */
 130                 }
 131                 /* Delays at least 10ms to give interface a chance */
 132                 mdelay(10);
 133                 status_val = HWIF(drive)->INB(IDE_SECTOR_REG);
 134         } while (status_val != 0x50 && status_val != 0x70);
 135
 136         if(status_val == 0x50)
 137                 return 0; /* device returned success */
 138         else
 139                 return 1; /* device returned failure */
 140 }
 141
 142 /*
 143  * pdc4030_identify sends a vendor-specific IDENTIFY command to the drive
 144  */
 145 int pdc4030_identify(ide_drive_t *drive)
 146 {
 147         return pdc4030_cmd(drive, PROMISE_IDENTIFY);
 148 }
 149
 150 /*
 151  * setup_pdc4030()
 152  * Completes the setup of a Promise DC4030 controller card, once found.
 153  */
 154 int __init setup_pdc4030(ide_hwif_t *hwif)
 155 {
 156         ide_drive_t *drive;
 157         ide_hwif_t *hwif2;
 158         struct dc_ident ident;
 159         int i;
 160         ide_startstop_t startstop;
 161
 162         if (!hwif) return 0;
 163
 164         drive = &hwif->drives[0];
 165         hwif2 = &ide_hwifs[hwif->index+1];
 166         if (hwif->chipset == ide_pdc4030) /* we've already been found ! */
 167                 return 1;
 168
 169         if (hwif->INB(IDE_NSECTOR_REG) == 0xFF ||
 170             hwif->INB(IDE_SECTOR_REG) == 0xFF) {
 171                 return 0;
 172         }
 173         if (IDE_CONTROL_REG)
 174                 hwif->OUTB(0x08, IDE_CONTROL_REG);
 175         if (pdc4030_cmd(drive,PROMISE_GET_CONFIG)) {
 176                 return 0;
 177         }
 178         if (ide_wait_stat(&startstop, drive,DATA_READY,BAD_W_STAT,WAIT_DRQ)) {
 179                 printk(KERN_INFO
 180                         "%s: Failed Promise read config!\n",hwif->name);
 181                 return 0;
 182         }
 183         hwif->ata_input_data(drive, &ident, SECTOR_WORDS);
 184         if (ident.id[1] != 'P' || ident.id[0] != 'T') {
 185                 return 0;
 186         }
 187         printk(KERN_INFO "%s: Promise caching controller, ",hwif->name);
 188         switch(ident.type) {
 189                 case 0x43:      printk("DC4030VL-2, "); break;
 190                 case 0x41:      printk("DC4030VL-1, "); break;
 191                 case 0x40:      printk("DC4030VL, "); break;
 192                 default:
 193                         printk("unknown - type 0x%02x - please report!\n"
 194                                ,ident.type);
 195                         printk("Please e-mail the following data to "
 196                                "promise@pnd-pc.demon.co.uk along with\n"
 197                                "a description of your card and drives:\n");
 198                         for (i=0; i < 0x90; i++) {
 199                                 printk("%02x ", ((unsigned char *)&ident)[i]);
 200                                 if ((i & 0x0f) == 0x0f) printk("\n");
 201                         }
 202                         return 0;
 203         }
 204         printk("%dKB cache, ",(int)ident.cache_mem);
 205         switch(ident.irq) {
 206             case 0x00: hwif->irq = 14; break;
 207             case 0x01: hwif->irq = 12; break;
 208             default:   hwif->irq = 15; break;
 209         }
 210         printk("on IRQ %d\n",hwif->irq);
 211
 212         /*
 213          * Once found and identified, we set up the next hwif in the array
 214          * (hwif2 = ide_hwifs[hwif->index+1]) with the same io ports, irq
 215          * and other settings as the main hwif. This gives us two "mated"
 216          * hwifs pointing to the Promise card.
 217          *
 218          * We also have to shift the default values for the remaining
 219          * interfaces "up by one" to make room for the second interface on the
 220          * same set of values.
 221          */
 222
 223         hwif->chipset   = hwif2->chipset = ide_pdc4030;
 224         hwif->mate      = hwif2;
 225         hwif2->mate     = hwif;
 226         hwif2->channel  = 1;
 227         hwif->rqsize    = hwif2->rqsize = 127;
 228         hwif->no_lba48 = hwif2->no_lba48 = 1;
 229         hwif->selectproc = hwif2->selectproc = &promise_selectproc;
 230         hwif->serialized = hwif2->serialized = 1;
 231         /* DC4030 hosted drives need their own identify... */
 232         hwif->identify = hwif2->identify = &pdc4030_identify;
 233
 234         /* Override the normal ide disk read/write. */
 235         hwif->rw_disk = promise_rw_disk;
 236         hwif2->rw_disk = promise_rw_disk;
 237
 238         /* Shift the remaining interfaces up by one */
 239         for (i=MAX_HWIFS-1 ; i > hwif->index+1 ; i--) {
 240                 ide_hwif_t *h = &ide_hwifs[i];
 241
 242 #ifdef DEBUG
 243                 printk(KERN_DEBUG "pdc4030: Shifting i/f %d values to i/f %d\n",i-1,i);
 244 #endif /* DEBUG */
 245                 ide_init_hwif_ports(&h->hw, (h-1)->io_ports[IDE_DATA_OFFSET], 0, NULL);
 246                 memcpy(h->io_ports, h->hw.io_ports, sizeof(h->io_ports));
 247                 h->noprobe = (h-1)->noprobe;
 248         }
 249         ide_init_hwif_ports(&hwif2->hw, hwif->io_ports[IDE_DATA_OFFSET], 0, NULL);
 250         memcpy(hwif2->io_ports, hwif->hw.io_ports, sizeof(hwif2->io_ports));
 251         hwif2->irq = hwif->irq;
 252         hwif2->hw.irq = hwif->hw.irq = hwif->irq;
 253         for (i=0; i<2 ; i++) {
 254                 hwif->drives[i].io_32bit = 3;
 255                 hwif2->drives[i].io_32bit = 3;
 256                 hwif->drives[i].keep_settings = 1;
 257                 hwif2->drives[i].keep_settings = 1;
 258                 if (!ident.current_tm[i].cyl)
 259                         hwif->drives[i].noprobe = 1;
 260                 if (!ident.current_tm[i+2].cyl)
 261                         hwif2->drives[i].noprobe = 1;
 262         }
 263
 264         probe_hwif_init(&ide_hwifs[hwif->index]);
 265         probe_hwif_init(&ide_hwifs[hwif2->index]);
 266
 267         return 1;
 268 }
 269
 270 /*
 271  * detect_pdc4030()
 272  * Tests for the presence of a DC4030 Promise card on this interface
 273  * Returns: 1 if found, 0 if not found
 274  */
 275 int __init detect_pdc4030(ide_hwif_t *hwif)
 276 {
 277         ide_drive_t *drive = &hwif->drives[0];
 278
 279         if (IDE_DATA_REG == 0) { /* Skip test for non-existent interface */
 280                 return 0;
 281         }
 282         hwif->OUTB(0xF3, IDE_SECTOR_REG);
 283         hwif->OUTB(0x14, IDE_SELECT_REG);
 284         hwif->OUTB(PROMISE_EXTENDED_COMMAND, IDE_COMMAND_REG);
 285
 286         msleep(50);
 287
 288         if (hwif->INB(IDE_ERROR_REG) == 'P' &&
 289             hwif->INB(IDE_NSECTOR_REG) == 'T' &&
 290             hwif->INB(IDE_SECTOR_REG) == 'I') {
 291                 return 1;
 292         } else {
 293                 return 0;
 294         }
 295 }
 296
 297 int __init pdc4030_init(void)
 298 {
 299         unsigned int    index;
 300         ide_hwif_t      *hwif;
 301
 302         for (index = 0; index < MAX_HWIFS; index++) {
 303                 hwif = &ide_hwifs[index];
 304                 if (hwif->chipset == ide_unknown && detect_pdc4030(hwif)) {
 305                         if (!setup_pdc4030(hwif))
 306                                 return -ENODEV;
 307                         return 0;
 308                 }
 309         }
 310         return -ENODEV;
 311 }
 312
 313 #ifdef MODULE
 314 module_init(pdc4030_init);
 315 #endif
 316
 317 MODULE_AUTHOR("Peter Denison");
 318 MODULE_DESCRIPTION("Support of Promise 4030 VLB series IDE chipsets");
 319 MODULE_LICENSE("GPL");
 320
 321 /*
 322  * promise_read_intr() is the handler for disk read/multread interrupts
 323  */
 324 static ide_startstop_t promise_read_intr (ide_drive_t *drive)
 325 {
 326         unsigned int sectors_left, sectors_avail, nsect;
 327         struct request *rq = HWGROUP(drive)->rq;
 328         ata_status_t status;
 329
 330         status.all = HWIF(drive)->INB(IDE_STATUS_REG);
 331         if (!OK_STAT(status.all, DATA_READY, BAD_R_STAT))
 332                 return DRIVER(drive)->error(drive, __FUNCTION__, status.all);
 333
 334 read_again:
 335         do {
 336                 sectors_left = HWIF(drive)->INB(IDE_NSECTOR_REG);
 337                 HWIF(drive)->INB(IDE_SECTOR_REG);
 338         } while (HWIF(drive)->INB(IDE_NSECTOR_REG) != sectors_left);
 339         sectors_avail = rq->nr_sectors - sectors_left;
 340         if (!sectors_avail)
 341                 goto read_again;
 342
 343 read_next:
 344         nsect = rq->current_nr_sectors;
 345         if (nsect > sectors_avail)
 346                 nsect = sectors_avail;
 347         sectors_avail -= nsect;
 348
 349 #ifdef DEBUG_READ
 350         printk(KERN_DEBUG "%s: %s: sectors(%lu-%lu), rem=%lu\n",
 351                           drive->name, __FUNCTION__,
 352                           (unsigned long)rq->sector,
 353                           (unsigned long)rq->sector + nsect - 1,
 354                           (unsigned long)rq->nr_sectors - nsect);
 355 #endif /* DEBUG_READ */
 356
 357         HWIF(drive)->ata_input_data(drive, rq->buffer, nsect * SECTOR_WORDS);
 358         rq->buffer += nsect<<9;
 359         rq->sector += nsect;
 360         rq->errors = 0;
 361         rq->nr_sectors -= nsect;
 362         if (!rq->current_nr_sectors)
 363                 DRIVER(drive)->end_request(drive, 1, 0);
 364
 365 /*
 366  * Now the data has been read in, do the following:
 367  *
 368  * if there are still sectors left in the request,
 369  *   if we know there are still sectors available from the interface,
 370  *     go back and read the next bit of the request.
 371  *   else if DRQ is asserted, there are more sectors available, so
 372  *     go back and find out how many, then read them in.
 373  *   else if BUSY is asserted, we are going to get an interrupt, so
 374  *     set the handler for the interrupt and just return
 375  */
 376         if (rq->nr_sectors > 0) {
 377                 if (sectors_avail)
 378                         goto read_next;
 379                 status.all = HWIF(drive)->INB(IDE_STATUS_REG);
 380                 if (status.b.drq)
 381                         goto read_again;
 382                 if (status.b.bsy) {
 383                         if (HWGROUP(drive)->handler != NULL)
 384                                 BUG();
 385                         ide_set_handler(drive,
 386                                         &promise_read_intr,
 387                                         WAIT_CMD,
 388                                         NULL);
 389 #ifdef DEBUG_READ
 390                         printk(KERN_DEBUG "%s: promise_read: waiting for"
 391                                "interrupt\n", drive->name);
 392 #endif /* DEBUG_READ */
 393                         return ide_started;
 394                 }
 395                 printk(KERN_ERR "%s: Eeek! promise_read_intr: sectors left "
 396                        "!DRQ !BUSY\n", drive->name);
 397                 return DRIVER(drive)->error(drive,
 398                                 "promise read intr", status.all);
 399         }
 400         return ide_stopped;
 401 }
 402
 403 /*
 404  * promise_complete_pollfunc()
 405  * This is the polling function for waiting (nicely!) until drive stops
 406  * being busy. It is invoked at the end of a write, after the previous poll
 407  * has finished.
 408  *
 409  * Once not busy, the end request is called.
 410  */
 411 static ide_startstop_t promise_complete_pollfunc(ide_drive_t *drive)
 412 {
 413         ide_hwgroup_t *hwgroup = HWGROUP(drive);
 414         struct request *rq = &hwgroup->wrq;
 415         struct bio *bio = rq->bio;
 416
 417         if ((HWIF(drive)->INB(IDE_STATUS_REG)) & BUSY_STAT) {
 418                 if (time_before(jiffies, hwgroup->poll_timeout)) {
 419                         if (hwgroup->handler != NULL)
 420                                 BUG();
 421                         ide_set_handler(drive,
 422                                         &promise_complete_pollfunc,
 423                                         HZ/100,
 424                                         NULL);
 425                         return ide_started; /* continue polling... */
 426                 }
 427                 hwgroup->poll_timeout = 0;
 428                 printk(KERN_ERR "%s: completion timeout - still busy!\n",
 429                        drive->name);
 430                 return DRIVER(drive)->error(drive, "busy timeout",
 431                                 HWIF(drive)->INB(IDE_STATUS_REG));
 432         }
 433
 434         hwgroup->poll_timeout = 0;
 435 #ifdef DEBUG_WRITE
 436         printk(KERN_DEBUG "%s: Write complete - end_request\n", drive->name);
 437 #endif /* DEBUG_WRITE */
 438
 439         bio->bi_idx = bio->bi_vcnt - rq->nr_cbio_segments;
 440         rq = hwgroup->rq;
 441         DRIVER(drive)->end_request(drive, 1, rq->hard_nr_sectors);
 442
 443         return ide_stopped;
 444 }
 445
 446 /*
 447  * promise_multwrite() transfers a block of up to mcount sectors of data
 448  * to a drive as part of a disk multiple-sector write operation.
 449  */
 450 static void promise_multwrite (ide_drive_t *drive, unsigned int mcount)
 451 {
 452         ide_hwgroup_t *hwgroup  = HWGROUP(drive);
 453         struct request *rq      = &hwgroup->wrq;
 454
 455         do {
 456                 char *buffer;
 457                 int nsect = rq->current_nr_sectors;
 458
 459                 if (nsect > mcount)
 460                         nsect = mcount;
 461                 mcount -= nsect;
 462                 buffer = rq->buffer;
 463
 464                 rq->sector += nsect;
 465                 rq->buffer += nsect << 9;
 466                 rq->nr_sectors -= nsect;
 467                 rq->current_nr_sectors -= nsect;
 468
 469                 /* Do we move to the next bh after this? */
 470                 if (!rq->current_nr_sectors) {
 471                         struct bio *bio = rq->bio;
 472
 473                         /*
 474                          * only move to next bio, when we have processed
 475                          * all bvecs in this one.
 476                          */
 477                         if (++bio->bi_idx >= bio->bi_vcnt) {
 478                                 bio->bi_idx = bio->bi_vcnt - rq->nr_cbio_segments;
 479                                 bio = bio->bi_next;
 480                         }
 481
 482                         /* end early early we ran out of requests */
 483                         if (!bio) {
 484                                 mcount = 0;
 485                         } else {
 486                                 rq->bio = bio;
 487                                 rq->nr_cbio_segments = bio_segments(bio);
 488                                 rq->current_nr_sectors = bio_cur_sectors(bio);
 489                                 rq->hard_cur_sectors = rq->current_nr_sectors;
 490                         }
 491                 }
 492
 493                 /*
 494                  * Ok, we're all setup for the interrupt
 495                  * re-entering us on the last transfer.
 496                  */
 497                 taskfile_output_data(drive, buffer, nsect<<7);
 498         } while (mcount);
 499 }
 500
 501 /*
 502  * promise_write_pollfunc() is the handler for disk write completion polling.
 503  */
 504 static ide_startstop_t promise_write_pollfunc (ide_drive_t *drive)
 505 {
 506         ide_hwgroup_t *hwgroup = HWGROUP(drive);
 507         struct request *rq = &hwgroup->wrq;
 508         struct bio *bio = rq->bio;
 509
 510         if (HWIF(drive)->INB(IDE_NSECTOR_REG) != 0) {
 511                 if (time_before(jiffies, hwgroup->poll_timeout)) {
 512                         if (hwgroup->handler != NULL)
 513                                 BUG();
 514                         ide_set_handler(drive,
 515                                         &promise_write_pollfunc,
 516                                         HZ/100,
 517                                         NULL);
 518                         return ide_started; /* continue polling... */
 519                 }
 520                 hwgroup->poll_timeout = 0;
 521                 printk(KERN_ERR "%s: write timed-out!\n",drive->name);
 522                 bio->bi_idx = bio->bi_vcnt - rq->nr_cbio_segments;
 523                 return DRIVER(drive)->error(drive, "write timeout",
 524                                 HWIF(drive)->INB(IDE_STATUS_REG));
 525         }
 526
 527         /*
 528          * Now write out last 4 sectors and poll for not BUSY
 529          */
 530         promise_multwrite(drive, 4);
 531         hwgroup->poll_timeout = jiffies + WAIT_WORSTCASE;
 532         if (hwgroup->handler != NULL)
 533                 BUG();
 534         ide_set_handler(drive, &promise_complete_pollfunc, HZ/100, NULL);
 535 #ifdef DEBUG_WRITE
 536         printk(KERN_DEBUG "%s: Done last 4 sectors - status = %02x\n",
 537                 drive->name, HWIF(drive)->INB(IDE_STATUS_REG));
 538 #endif /* DEBUG_WRITE */
 539         return ide_started;
 540 }
 541
 542 /*
 543  * promise_write() transfers a block of one or more sectors of data to a
 544  * drive as part of a disk write operation. All but 4 sectors are transferred
 545  * in the first attempt, then the interface is polled (nicely!) for completion
 546  * before the final 4 sectors are transferred. There is no interrupt generated
 547  * on writes (at least on the DC4030VL-2), we just have to poll for NOT BUSY.
 548  */
 549 static ide_startstop_t promise_write (ide_drive_t *drive)
 550 {
 551         ide_hwgroup_t *hwgroup = HWGROUP(drive);
 552         struct request *rq = &hwgroup->wrq;
 553
 554 #ifdef DEBUG_WRITE
 555         printk(KERN_DEBUG "%s: %s: sectors(%lu-%lu)\n",
 556                           drive->name, __FUNCTION__,
 557                           (unsigned long)rq->sector,
 558                           (unsigned long)rq->sector + rq->nr_sectors - 1);
 559 #endif /* DEBUG_WRITE */
 560
 561         /*
 562          * If there are more than 4 sectors to transfer, do n-4 then go into
 563          * the polling strategy as defined above.
 564          */
 565         if (rq->nr_sectors > 4) {
 566                 promise_multwrite(drive, rq->nr_sectors - 4);
 567                 hwgroup->poll_timeout = jiffies + WAIT_WORSTCASE;
 568                 if (hwgroup->handler != NULL)   /* paranoia check */
 569                         BUG();
 570                 ide_set_handler (drive, &promise_write_pollfunc, HZ/100, NULL);
 571                 return ide_started;
 572         } else {
 573         /*
 574          * There are 4 or fewer sectors to transfer, do them all in one go
 575          * and wait for NOT BUSY.
 576          */
 577                 promise_multwrite(drive, rq->nr_sectors);
 578                 hwgroup->poll_timeout = jiffies + WAIT_WORSTCASE;
 579                 if (hwgroup->handler != NULL)
 580                         BUG();
 581                 ide_set_handler(drive,
 582                                 &promise_complete_pollfunc,
 583                                 HZ/100,
 584                                 NULL);
 585
 586 #ifdef DEBUG_WRITE
 587                 printk(KERN_DEBUG "%s: promise_write: <= 4 sectors, "
 588                         "status = %02x\n", drive->name,
 589                         HWIF(drive)->INB(IDE_STATUS_REG));
 590 #endif /* DEBUG_WRITE */
 591                 return ide_started;
 592         }
 593 }
 594
 595 /*
 596  * do_pdc4030_io() is called from promise_rw_disk, having had the block number
 597  * already set up. It issues a READ or WRITE command to the Promise
 598  * controller, assuming LBA has been used to set up the block number.
 599  */
 600 ide_startstop_t do_pdc4030_io (ide_drive_t *drive, struct request *rq)
 601 {
 602         ide_startstop_t startstop;
 603         unsigned long timeout;
 604         u8 stat = 0;
 605
 606         if (rq_data_dir(rq) == READ) {
 607                 HWIF(drive)->OUTB(PROMISE_READ, IDE_COMMAND_REG);
 608 /*
 609  * The card's behaviour is odd at this point. If the data is
 610  * available, DRQ will be true, and no interrupt will be
 611  * generated by the card. If this is the case, we need to call the
 612  * "interrupt" handler (promise_read_intr) directly. Otherwise, if
 613  * an interrupt is going to occur, bit0 of the SELECT register will
 614  * be high, so we can set the handler the just return and be interrupted.
 615  * If neither of these is the case, we wait for up to 50ms (badly I'm
 616  * afraid!) until one of them is.
 617  */
 618                 timeout = jiffies + HZ/20; /* 50ms wait */
 619                 do {
 620                         stat = HWIF(drive)->INB(IDE_STATUS_REG);
 621                         if (stat & DRQ_STAT) {
 622                                 udelay(1);
 623                                 return promise_read_intr(drive);
 624                         }
 625                         if (HWIF(drive)->INB(IDE_SELECT_REG) & 0x01) {
 626 #ifdef DEBUG_READ
 627                                 printk(KERN_DEBUG "%s: read: waiting for "
 628                                                 "interrupt\n", drive->name);
 629 #endif /* DEBUG_READ */
 630                                 ide_set_handler(drive,
 631                                                 &promise_read_intr,
 632                                                 WAIT_CMD,
 633                                                 NULL);
 634                                 return ide_started;
 635                         }
 636                         udelay(1);
 637                 } while (time_before(jiffies, timeout));
 638
 639                 printk(KERN_ERR "%s: reading: No DRQ and not "
 640                                 "waiting - Odd!\n", drive->name);
 641                 return ide_stopped;
 642         } else {
 643                 HWIF(drive)->OUTB(PROMISE_WRITE, IDE_COMMAND_REG);
 644                 if (ide_wait_stat(&startstop, drive, DATA_READY,
 645                                 drive->bad_wstat, WAIT_DRQ)) {
 646                         printk(KERN_ERR "%s: no DRQ after issuing "
 647                                 "PROMISE_WRITE\n", drive->name);
 648                         return startstop;
 649                 }
 650                 if (!drive->unmask)
 651                         local_irq_disable();
 652                 HWGROUP(drive)->wrq = *rq; /* scratchpad */
 653                 return promise_write(drive);
 654         }
 655 }
 656
 657 static ide_startstop_t promise_rw_disk (ide_drive_t *drive, struct request *rq, sector_t block)
 658 {
 659         /* The four drives on the two logical (one physical) interfaces
 660            are distinguished by writing the drive number (0-3) to the
 661            Feature register.
 662            FIXME: Is promise_selectproc now redundant??
 663         */
 664         ide_hwif_t *hwif = HWIF(drive);
 665         int drive_number = (hwif->channel << 1) + drive->select.b.unit;
 666
 667         BUG_ON(rq->nr_sectors > 127);
 668
 669         if (IDE_CONTROL_REG)
 670                 hwif->OUTB(drive->ctl, IDE_CONTROL_REG);
 671         hwif->OUTB(drive_number, IDE_FEATURE_REG);
 672         hwif->OUTB(rq->nr_sectors, IDE_NSECTOR_REG);
 673         hwif->OUTB(block,IDE_SECTOR_REG);
 674         hwif->OUTB(block>>=8,IDE_LCYL_REG);
 675         hwif->OUTB(block>>=8,IDE_HCYL_REG);
 676         hwif->OUTB(((block>>8)&0x0f)|drive->select.all,IDE_SELECT_REG);
 677
 678         return do_pdc4030_io(drive, rq);
 679 }