drivers/ide/legacy/hd98.c

   1 /*
   2  *  Copyright (C) 1991, 1992  Linus Torvalds
   3  *
   4  * This is the low-level hd interrupt support. It traverses the
   5  * request-list, using interrupts to jump between functions. As
   6  * all the functions are called within interrupts, we may not
   7  * sleep. Special care is recommended.
   8  *
   9  *  modified by Drew Eckhardt to check nr of hd's from the CMOS.
  10  *
  11  *  Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug
  12  *  in the early extended-partition checks and added DM partitions
  13  *
  14  *  IRQ-unmask, drive-id, multiple-mode, support for ">16 heads",
  15  *  and general streamlining by Mark Lord.
  16  *
  17  *  Removed 99% of above. Use Mark's ide driver for those options.
  18  *  This is now a lightweight ST-506 driver. (Paul Gortmaker)
  19  *
  20  *  Modified 1995 Russell King for ARM processor.
  21  *
  22  *  Bugfix: max_sectors must be <= 255 or the wheels tend to come
  23  *  off in a hurry once you queue things up - Paul G. 02/2001
  24  */
  25
  26 /* Uncomment the following if you want verbose error reports. */
  27 /* #define VERBOSE_ERRORS */
  28
  29 #include <linux/errno.h>
  30 #include <linux/signal.h>
  31 #include <linux/sched.h>
  32 #include <linux/timer.h>
  33 #include <linux/fs.h>
  34 #include <linux/kernel.h>
  35 #include <linux/genhd.h>
  36 #include <linux/slab.h>
  37 #include <linux/string.h>
  38 #include <linux/ioport.h>
  39 #include <linux/mc146818rtc.h> /* CMOS defines */
  40 #include <linux/init.h>
  41 #include <linux/blkpg.h>
  42 #include <linux/hdreg.h>
  43
  44 #define REALLY_SLOW_IO
  45 #include <asm/system.h>
  46 #include <asm/io.h>
  47 #include <asm/uaccess.h>
  48
  49 #include "io_ports.h"
  50
  51 #ifdef __arm__
  52 #undef  HD_IRQ
  53 #endif
  54 #include <asm/irq.h>
  55 #ifdef __arm__
  56 #define HD_IRQ IRQ_HARDDISK
  57 #endif
  58
  59 /* Hd controller regster ports */
  60
  61 #define HD_DATA         0x640   /* _CTL when writing */
  62 #define HD_ERROR        0x642   /* see err-bits */
  63 #define HD_NSECTOR      0x644   /* nr of sectors to read/write */
  64 #define HD_SECTOR       0x646   /* starting sector */
  65 #define HD_LCYL         0x648   /* starting cylinder */
  66 #define HD_HCYL         0x64a   /* high byte of starting cyl */
  67 #define HD_CURRENT      0x64c   /* 101dhhhh , d=drive, hhhh=head */
  68 #define HD_STATUS       0x64e   /* see status-bits */
  69 #define HD_FEATURE      HD_ERROR        /* same io address, read=error, write=feature */
  70 #define HD_PRECOMP      HD_FEATURE      /* obsolete use of this port - predates IDE */
  71 #define HD_COMMAND      HD_STATUS       /* same io address, read=status, write=cmd */
  72
  73 #define HD_CMD          0x74c   /* used for resets */
  74 #define HD_ALTSTATUS    0x74c   /* same as HD_STATUS but doesn't clear irq */
  75
  76 /* Bits of HD_STATUS */
  77 #define ERR_STAT                0x01
  78 #define INDEX_STAT              0x02
  79 #define ECC_STAT                0x04    /* Corrected error */
  80 #define DRQ_STAT                0x08
  81 #define SEEK_STAT               0x10
  82 #define SERVICE_STAT            SEEK_STAT
  83 #define WRERR_STAT              0x20
  84 #define READY_STAT              0x40
  85 #define BUSY_STAT               0x80
  86
  87 /* Bits for HD_ERROR */
  88 #define MARK_ERR                0x01    /* Bad address mark */
  89 #define TRK0_ERR                0x02    /* couldn't find track 0 */
  90 #define ABRT_ERR                0x04    /* Command aborted */
  91 #define MCR_ERR                 0x08    /* media change request */
  92 #define ID_ERR                  0x10    /* ID field not found */
  93 #define MC_ERR                  0x20    /* media changed */
  94 #define ECC_ERR                 0x40    /* Uncorrectable ECC error */
  95 #define BBD_ERR                 0x80    /* pre-EIDE meaning:  block marked bad */
  96 #define ICRC_ERR                0x80    /* new meaning:  CRC error during transfer */
  97
  98 static spinlock_t hd_lock = SPIN_LOCK_UNLOCKED;
  99 static struct request_queue *hd_queue;
 100
 101 #define CURRENT elv_next_request(hd_queue)
 102
 103 #define TIMEOUT_VALUE   (6*HZ)
 104 #define HD_DELAY        0
 105
 106 #define MAX_ERRORS     16       /* Max read/write errors/sector */
 107 #define RESET_FREQ      8       /* Reset controller every 8th retry */
 108 #define RECAL_FREQ      4       /* Recalibrate every 4th retry */
 109 #define MAX_HD          2
 110
 111 #define STAT_OK         (READY_STAT|SEEK_STAT)
 112 #define OK_STATUS(s)    (((s)&(STAT_OK|(BUSY_STAT|WRERR_STAT|ERR_STAT)))==STAT_OK)
 113
 114 static void recal_intr(void);
 115 static void bad_rw_intr(void);
 116
 117 static int reset;
 118 static int hd_error;
 119
 120 /*
 121  *  This struct defines the HD's and their types.
 122  */
 123 struct hd_i_struct {
 124         unsigned int head,sect,cyl,wpcom,lzone,ctl;
 125         int unit;
 126         int recalibrate;
 127         int special_op;
 128 };
 129
 130 #ifdef HD_TYPE
 131 static struct hd_i_struct hd_info[] = { HD_TYPE };
 132 static int NR_HD = ((sizeof (hd_info))/(sizeof (struct hd_i_struct)));
 133 #else
 134 static struct hd_i_struct hd_info[MAX_HD];
 135 static int NR_HD;
 136 #endif
 137
 138 static struct gendisk *hd_gendisk[MAX_HD];
 139
 140 static struct timer_list device_timer;
 141
 142 #define TIMEOUT_VALUE (6*HZ)
 143
 144 #define SET_TIMER                                                       \
 145         do {                                                            \
 146                 mod_timer(&device_timer, jiffies + TIMEOUT_VALUE);      \
 147         } while (0)
 148
 149 static void (*do_hd)(void) = NULL;
 150 #define SET_HANDLER(x) \
 151 if ((do_hd = (x)) != NULL) \
 152         SET_TIMER; \
 153 else \
 154         del_timer(&device_timer);
 155
 156
 157 #if (HD_DELAY > 0)
 158 unsigned long last_req;
 159
 160 unsigned long read_timer(void)
 161 {
 162         extern spinlock_t i8253_lock;
 163         unsigned long t, flags;
 164         int i;
 165
 166         spin_lock_irqsave(&i8253_lock, flags);
 167         t = jiffies * 11932;
 168         outb_p(0, PIT_MODE);
 169         i = inb_p(PIT_CH0);
 170         i |= inb(PIT_CH0) << 8;
 171         spin_unlock_irqrestore(&i8253_lock, flags);
 172         return(t - i);
 173 }
 174 #endif
 175
 176 void __init hd_setup(char *str, int *ints)
 177 {
 178         int hdind = 0;
 179
 180         if (ints[0] != 3)
 181                 return;
 182         if (hd_info[0].head != 0)
 183                 hdind=1;
 184         hd_info[hdind].head = ints[2];
 185         hd_info[hdind].sect = ints[3];
 186         hd_info[hdind].cyl = ints[1];
 187         hd_info[hdind].wpcom = 0;
 188         hd_info[hdind].lzone = ints[1];
 189         hd_info[hdind].ctl = (ints[2] > 8 ? 8 : 0);
 190         NR_HD = hdind+1;
 191 }
 192
 193 static void dump_status (const char *msg, unsigned int stat)
 194 {
 195         char *name = CURRENT ?
 196                         CURRENT->rq_dev->bd_disk->disk_name :
 197                         "hd?";
 198 #ifdef VERBOSE_ERRORS
 199         printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
 200         if (stat & BUSY_STAT)   printk("Busy ");
 201         if (stat & READY_STAT)  printk("DriveReady ");
 202         if (stat & WRERR_STAT)  printk("WriteFault ");
 203         if (stat & SEEK_STAT)   printk("SeekComplete ");
 204         if (stat & DRQ_STAT)    printk("DataRequest ");
 205         if (stat & ECC_STAT)    printk("CorrectedError ");
 206         if (stat & INDEX_STAT)  printk("Index ");
 207         if (stat & ERR_STAT)    printk("Error ");
 208         printk("}\n");
 209         if ((stat & ERR_STAT) == 0) {
 210                 hd_error = 0;
 211         } else {
 212                 hd_error = inb(HD_ERROR);
 213                 printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff);
 214                 if (hd_error & BBD_ERR)         printk("BadSector ");
 215                 if (hd_error & ECC_ERR)         printk("UncorrectableError ");
 216                 if (hd_error & ID_ERR)          printk("SectorIdNotFound ");
 217                 if (hd_error & ABRT_ERR)        printk("DriveStatusError ");
 218                 if (hd_error & TRK0_ERR)        printk("TrackZeroNotFound ");
 219                 if (hd_error & MARK_ERR)        printk("AddrMarkNotFound ");
 220                 printk("}");
 221                 if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) {
 222                         printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL),
 223                                 inb(HD_CURRENT) & 0xf, inb(HD_SECTOR));
 224                         if (CURRENT)
 225                                 printk(", sector=%ld", CURRENT->sector);
 226                 }
 227                 printk("\n");
 228         }
 229 #else
 230         printk("%s: %s: status=0x%02x.\n", name, msg, stat & 0xff);
 231         if ((stat & ERR_STAT) == 0) {
 232                 hd_error = 0;
 233         } else {
 234                 hd_error = inb(HD_ERROR);
 235                 printk("%s: %s: error=0x%02x.\n", name, msg, hd_error & 0xff);
 236         }
 237 #endif
 238 }
 239
 240 void check_status(void)
 241 {
 242         int i = inb(HD_STATUS);
 243
 244         if (!OK_STATUS(i)) {
 245                 dump_status("check_status", i);
 246                 bad_rw_intr();
 247         }
 248 }
 249
 250 static int controller_busy(void)
 251 {
 252         int retries = 100000;
 253         unsigned char status;
 254
 255         do {
 256                 status = inb(HD_STATUS);
 257         } while ((status & BUSY_STAT) && --retries);
 258         return status;
 259 }
 260
 261 static int status_ok(void)
 262 {
 263         unsigned char status = inb(HD_STATUS);
 264
 265         if (status & BUSY_STAT)
 266                 return 1;       /* Ancient, but does it make sense??? */
 267         if (status & WRERR_STAT)
 268                 return 0;
 269         if (!(status & READY_STAT))
 270                 return 0;
 271         if (!(status & SEEK_STAT))
 272                 return 0;
 273         return 1;
 274 }
 275
 276 static int controller_ready(unsigned int drive, unsigned int head)
 277 {
 278         int retry = 100;
 279
 280         do {
 281                 if (controller_busy() & BUSY_STAT)
 282                         return 0;
 283                 outb(0xA0 | (drive<<4) | head, HD_CURRENT);
 284                 if (status_ok())
 285                         return 1;
 286         } while (--retry);
 287         return 0;
 288 }
 289
 290 static void hd_out(struct hd_i_struct *disk,
 291                    unsigned int nsect,
 292                    unsigned int sect,
 293                    unsigned int head,
 294                    unsigned int cyl,
 295                    unsigned int cmd,
 296                    void (*intr_addr)(void))
 297 {
 298         unsigned short port;
 299
 300 #if (HD_DELAY > 0)
 301         while (read_timer() - last_req < HD_DELAY)
 302                 /* nothing */;
 303 #endif
 304         if (reset)
 305                 return;
 306         if (!controller_ready(disk->unit, head)) {
 307                 reset = 1;
 308                 return;
 309         }
 310         SET_HANDLER(intr_addr);
 311         outb(disk->ctl,HD_CMD);
 312         port=HD_DATA + 2;
 313         outb(disk->wpcom>>2, port); port += 2;
 314         outb(nsect, port); port += 2;
 315         outb(sect, port); port += 2;
 316         outb(cyl, port); port += 2;
 317         outb(cyl>>8, port); port += 2;
 318         outb(0xA0|(disk->unit<<4)|head, port); port += 2;
 319         outb(cmd, port);
 320 }
 321
 322 static void hd_request (void);
 323
 324 static int drive_busy(void)
 325 {
 326         unsigned int i;
 327         unsigned char c;
 328
 329         for (i = 0; i < 500000 ; i++) {
 330                 c = inb(HD_STATUS);
 331                 if ((c & (BUSY_STAT | READY_STAT | SEEK_STAT)) == STAT_OK)
 332                         return 0;
 333         }
 334         dump_status("reset timed out", c);
 335         return 1;
 336 }
 337
 338 static void reset_controller(void)
 339 {
 340         int     i;
 341
 342         outb(4,HD_CMD);
 343         for(i = 0; i < 1000; i++) barrier();
 344         outb(hd_info[0].ctl & 0x0f,HD_CMD);
 345         for(i = 0; i < 1000; i++) barrier();
 346         if (drive_busy())
 347                 printk("hd: controller still busy\n");
 348         else if ((hd_error = inb(HD_ERROR)) != 1)
 349                 printk("hd: controller reset failed: %02x\n",hd_error);
 350 }
 351
 352 static void reset_hd(void)
 353 {
 354         static int i;
 355
 356 repeat:
 357         if (reset) {
 358                 reset = 0;
 359                 i = -1;
 360                 reset_controller();
 361         } else {
 362                 check_status();
 363                 if (reset)
 364                         goto repeat;
 365         }
 366         if (++i < NR_HD) {
 367                 struct hd_i_struct *disk = &hd_info[i];
 368                 disk->special_op = disk->recalibrate = 1;
 369                 hd_out(disk, disk->sect, disk->sect, disk->head-1,
 370                         disk->cyl, WIN_SPECIFY, &reset_hd);
 371                 if (reset)
 372                         goto repeat;
 373         } else
 374                 hd_request();
 375 }
 376
 377 /*
 378  * Ok, don't know what to do with the unexpected interrupts: on some machines
 379  * doing a reset and a retry seems to result in an eternal loop. Right now I
 380  * ignore it, and just set the timeout.
 381  *
 382  * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the
 383  * drive enters "idle", "standby", or "sleep" mode, so if the status looks
 384  * "good", we just ignore the interrupt completely.
 385  */
 386 void unexpected_hd_interrupt(void)
 387 {
 388         unsigned int stat = inb(HD_STATUS);
 389
 390         if (stat & (BUSY_STAT|DRQ_STAT|ECC_STAT|ERR_STAT)) {
 391                 dump_status ("unexpected interrupt", stat);
 392                 SET_TIMER;
 393         }
 394 }
 395
 396 /*
 397  * bad_rw_intr() now tries to be a bit smarter and does things
 398  * according to the error returned by the controller.
 399  * -Mika Liljeberg (liljeber@cs.Helsinki.FI)
 400  */
 401 static void bad_rw_intr(void)
 402 {
 403         struct request *req = CURRENT;
 404         struct hd_i_struct *disk;
 405
 406         if (!req)
 407                 return;
 408         disk = req->rq_disk->private_data;
 409         if (++req->errors >= MAX_ERRORS || (hd_error & BBD_ERR)) {
 410                 end_request(req, 0);
 411                 disk->special_op = disk->recalibrate = 1;
 412         } else if (req->errors % RESET_FREQ == 0)
 413                 reset = 1;
 414         else if ((hd_error & TRK0_ERR) || req->errors % RECAL_FREQ == 0)
 415                 disk->special_op = disk->recalibrate = 1;
 416         /* Otherwise just retry */
 417 }
 418
 419 static inline int wait_DRQ(void)
 420 {
 421         int retries = 100000, stat;
 422
 423         while (--retries > 0)
 424                 if ((stat = inb(HD_STATUS)) & DRQ_STAT)
 425                         return 0;
 426         dump_status("wait_DRQ", stat);
 427         return -1;
 428 }
 429
 430 static void read_intr(void)
 431 {
 432         int i, retries = 100000;
 433         struct request *req;
 434
 435         do {
 436                 i = (unsigned) inb(HD_STATUS);
 437                 if (i & BUSY_STAT)
 438                         continue;
 439                 if (!OK_STATUS(i))
 440                         break;
 441                 if (i & DRQ_STAT)
 442                         goto ok_to_read;
 443         } while (--retries > 0);
 444         dump_status("read_intr", i);
 445         bad_rw_intr();
 446         hd_request();
 447         return;
 448 ok_to_read:
 449         req = CURRENT;
 450         insw(HD_DATA,req->buffer,256);
 451         req->sector++;
 452         req->buffer += 512;
 453         req->errors = 0;
 454         i = --req->nr_sectors;
 455         --req->current_nr_sectors;
 456 #ifdef DEBUG
 457         printk("%s: read: sector %ld, remaining = %ld, buffer=%p\n",
 458                 req->rq_disk->disk_name, req->sector, req->nr_sectors,
 459                 req->buffer+512);
 460 #endif
 461         if (req->current_nr_sectors <= 0)
 462                 end_request(req, 1);
 463         if (i > 0) {
 464                 SET_HANDLER(&read_intr);
 465                 return;
 466         }
 467         (void) inb(HD_STATUS);
 468 #if (HD_DELAY > 0)
 469         last_req = read_timer();
 470 #endif
 471         if (CURRENT)
 472                 hd_request();
 473         return;
 474 }
 475
 476 static void write_intr(void)
 477 {
 478         int i;
 479         int retries = 100000;
 480         struct request *req = CURRENT;
 481
 482         do {
 483                 i = (unsigned) inb(HD_STATUS);
 484                 if (i & BUSY_STAT)
 485                         continue;
 486                 if (!OK_STATUS(i))
 487                         break;
 488                 if ((req->nr_sectors <= 1) || (i & DRQ_STAT))
 489                         goto ok_to_write;
 490         } while (--retries > 0);
 491         dump_status("write_intr", i);
 492         bad_rw_intr();
 493         hd_request();
 494         return;
 495 ok_to_write:
 496         req->sector++;
 497         i = --req->nr_sectors;
 498         --req->current_nr_sectors;
 499         req->buffer += 512;
 500         if (!i || (req->bio && req->current_nr_sectors < 1))
 501                 end_request(req, 1);
 502         if (i > 0) {
 503                 SET_HANDLER(&write_intr);
 504                 outsw(HD_DATA,req->buffer,256);
 505                 local_irq_enable();
 506         } else {
 507 #if (HD_DELAY > 0)
 508                 last_req = read_timer();
 509 #endif
 510                 hd_request();
 511         }
 512         return;
 513 }
 514
 515 static void recal_intr(void)
 516 {
 517         check_status();
 518 #if (HD_DELAY > 0)
 519         last_req = read_timer();
 520 #endif
 521         hd_request();
 522 }
 523
 524 /*
 525  * This is another of the error-routines I don't know what to do with. The
 526  * best idea seems to just set reset, and start all over again.
 527  */
 528 static void hd_times_out(unsigned long dummy)
 529 {
 530         do_hd = NULL;
 531
 532         if (!CURRENT)
 533                 return;
 534
 535         disable_irq(HD_IRQ);
 536         local_irq_enable();
 537         reset = 1;
 538         printk("%s: timeout\n", CURRENT->rq_disk->disk_name);
 539         if (++CURRENT->errors >= MAX_ERRORS) {
 540 #ifdef DEBUG
 541                 printk("%s: too many errors\n", CURRENT->rq_disk->disk_name);
 542 #endif
 543                 end_request(CURRENT, 0);
 544         }
 545         local_irq_disable();
 546         hd_request();
 547         enable_irq(HD_IRQ);
 548 }
 549
 550 int do_special_op(struct hd_i_struct *disk, struct request *req)
 551 {
 552         if (disk->recalibrate) {
 553                 disk->recalibrate = 0;
 554                 hd_out(disk, disk->sect,0,0,0,WIN_RESTORE,&recal_intr);
 555                 return reset;
 556         }
 557         if (disk->head > 16) {
 558                 printk ("%s: cannot handle device with more than 16 heads - giving up\n", req->rq_disk->disk_name);
 559                 end_request(req, 0);
 560         }
 561         disk->special_op = 0;
 562         return 1;
 563 }
 564
 565 /*
 566  * The driver enables interrupts as much as possible.  In order to do this,
 567  * (a) the device-interrupt is disabled before entering hd_request(),
 568  * and (b) the timeout-interrupt is disabled before the sti().
 569  *
 570  * Interrupts are still masked (by default) whenever we are exchanging
 571  * data/cmds with a drive, because some drives seem to have very poor
 572  * tolerance for latency during I/O. The IDE driver has support to unmask
 573  * interrupts for non-broken hardware, so use that driver if required.
 574  */
 575 static void hd_request(void)
 576 {
 577         unsigned int block, nsect, sec, track, head, cyl;
 578         struct hd_i_struct *disk;
 579         struct request *req;
 580
 581         if (do_hd)
 582                 return;
 583 repeat:
 584         del_timer(&device_timer);
 585         local_irq_enable();
 586
 587         if (!CURRENT) {
 588                 do_hd = NULL;
 589                 return;
 590         }
 591         req = CURRENT;
 592
 593         if (reset) {
 594                 local_irq_disable();
 595                 reset_hd();
 596                 return;
 597         }
 598         disk = req->rq_disk->private_data;
 599         block = req->sector;
 600         nsect = req->nr_sectors;
 601         if (block >= get_capacity(req->rq_disk) ||
 602             ((block+nsect) > get_capacity(req->rq_disk))) {
 603                 printk("%s: bad access: block=%d, count=%d\n",
 604                         req->rq_disk->disk_name, block, nsect);
 605                 end_request(req, 0);
 606                 goto repeat;
 607         }
 608
 609         if (disk->special_op) {
 610                 if (do_special_op(disk, req))
 611                         goto repeat;
 612                 return;
 613         }
 614         sec   = block % disk->sect + 1;
 615         track = block / disk->sect;
 616         head  = track % disk->head;
 617         cyl   = track / disk->head;
 618 #ifdef DEBUG
 619         printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n",
 620                 req->rq_disk->disk_name, (req->cmd == READ)?"read":"writ",
 621                 cyl, head, sec, nsect, req->buffer);
 622 #endif
 623         if (req->flags & REQ_CMD) {
 624                 switch (rq_data_dir(req)) {
 625                 case READ:
 626                         hd_out(disk,nsect,sec,head,cyl,WIN_READ,&read_intr);
 627                         if (reset)
 628                                 goto repeat;
 629                         break;
 630                 case WRITE:
 631                         hd_out(disk,nsect,sec,head,cyl,WIN_WRITE,&write_intr);
 632                         if (reset)
 633                                 goto repeat;
 634                         if (wait_DRQ()) {
 635                                 bad_rw_intr();
 636                                 goto repeat;
 637                         }
 638                         outsw(HD_DATA,req->buffer,256);
 639                         break;
 640                 default:
 641                         printk("unknown hd-command\n");
 642                         end_request(req, 0);
 643                         break;
 644                 }
 645         }
 646 }
 647
 648 static void do_hd_request (request_queue_t * q)
 649 {
 650         disable_irq(HD_IRQ);
 651         hd_request();
 652         enable_irq(HD_IRQ);
 653 }
 654
 655 static int hd_ioctl(struct inode * inode, struct file * file,
 656         unsigned int cmd, unsigned long arg)
 657 {
 658         struct hd_i_struct *disk = inode->i_bdev->bd_disk->private_data;
 659         struct hd_geometry *loc = (struct hd_geometry *) arg;
 660         struct hd_geometry g;
 661
 662         if (cmd != HDIO_GETGEO)
 663                 return -EINVAL;
 664         if (!loc)
 665                 return -EINVAL;
 666         g.heads = disk->head;
 667         g.sectors = disk->sect;
 668         g.cylinders = disk->cyl;
 669         g.start = get_start_sect(inode->i_bdev);
 670         return copy_to_user(loc, &g, sizeof g) ? -EFAULT : 0;
 671 }
 672
 673 /*
 674  * Releasing a block device means we sync() it, so that it can safely
 675  * be forgotten about...
 676  */
 677
 678 static void hd_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 679 {
 680         void (*handler)(void) = do_hd;
 681
 682         do_hd = NULL;
 683         del_timer(&device_timer);
 684         if (!handler)
 685                 handler = unexpected_hd_interrupt;
 686         handler();
 687         local_irq_enable();
 688 }
 689
 690 static struct block_device_operations hd_fops = {
 691         .ioctl =        hd_ioctl,
 692 };
 693
 694 /*
 695  * This is the hard disk IRQ description. The SA_INTERRUPT in sa_flags
 696  * means we run the IRQ-handler with interrupts disabled:  this is bad for
 697  * interrupt latency, but anything else has led to problems on some
 698  * machines.
 699  *
 700  * We enable interrupts in some of the routines after making sure it's
 701  * safe.
 702  */
 703
 704 static int __init hd_init(void)
 705 {
 706         int drive;
 707         if (register_blkdev(HD_MAJOR,"hd")) {
 708                 printk("hd: unable to get major %d for hard disk\n",HD_MAJOR);
 709                 return -1;
 710         }
 711         hd_queue = blk_init_queue(do_hd_request, &hd_lock);
 712         if (!hd_queue) {
 713                 unregister_blkdev(HD_MAJOR,"hd");
 714                 return -1;
 715         }
 716         blk_queue_max_sectors(hd_queue, 255);
 717         init_timer(&device_timer);
 718         device_timer.function = hd_times_out;
 719         blk_queue_hardsect_size(hd_queue, 512);
 720
 721 #ifdef __i386__
 722         if (!NR_HD) {
 723                 extern struct drive_info drive_info;
 724                 unsigned char *BIOS = (unsigned char *) &drive_info;
 725                 unsigned long flags;
 726 #ifndef CONFIG_X86_PC9800
 727                 int cmos_disks;
 728 #endif
 729
 730                 for (drive=0 ; drive<2 ; drive++) {
 731                         hd_info[drive].cyl = *(unsigned short *) BIOS;
 732                         hd_info[drive].head = *(3+BIOS);
 733                         hd_info[drive].sect = *(2+BIOS);
 734                         hd_info[drive].wpcom = 0;
 735                         hd_info[drive].ctl = *(3+BIOS) > 8 ? 8 : 0;
 736                         hd_info[drive].lzone = *(unsigned short *) BIOS;
 737                         if (hd_info[drive].cyl && NR_HD == drive)
 738                                 NR_HD++;
 739                         BIOS += 6;
 740                 }
 741
 742         }
 743 #endif /* __i386__ */
 744 #ifdef __arm__
 745         if (!NR_HD) {
 746                 /* We don't know anything about the drive.  This means
 747                  * that you *MUST* specify the drive parameters to the
 748                  * kernel yourself.
 749                  */
 750                 printk("hd: no drives specified - use hd=cyl,head,sectors"
 751                         " on kernel command line\n");
 752         }
 753 #endif
 754         if (!NR_HD)
 755                 goto out;
 756
 757         for (drive=0 ; drive < NR_HD ; drive++) {
 758                 struct gendisk *disk = alloc_disk(64);
 759                 struct hd_i_struct *p = &hd_info[drive];
 760                 if (!disk)
 761                         goto Enomem;
 762                 disk->major = HD_MAJOR;
 763                 disk->first_minor = drive << 6;
 764                 disk->fops = &hd_fops;
 765                 sprintf(disk->disk_name, "hd%c", 'a'+drive);
 766                 disk->private_data = p;
 767                 set_capacity(disk, p->head * p->sect * p->cyl);
 768                 disk->queue = hd_queue;
 769                 p->unit = drive;
 770                 hd_gendisk[drive] = disk;
 771                 printk ("%s: %luMB, CHS=%d/%d/%d\n",
 772                         disk->disk_name, (unsigned long)get_capacity(disk)/2048,
 773                         p->cyl, p->head, p->sect);
 774         }
 775
 776         if (request_irq(HD_IRQ, hd_interrupt, SA_INTERRUPT, "hd", NULL)) {
 777                 printk("hd: unable to get IRQ%d for the hard disk driver\n",
 778                         HD_IRQ);
 779                 goto out1;
 780         }
 781
 782         if (!request_region(HD_DATA, 2, "hd(data)")) {
 783                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
 784                 NR_HD = 0;
 785                 free_irq(HD_IRQ, NULL);
 786                 return;
 787         }
 788
 789         if (!request_region(HD_DATA + 2, 1, "hd"))
 790         {
 791                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
 792                 goto out2;
 793         }
 794
 795         if (!request_region(HD_DATA + 4, 1, "hd"))
 796         {
 797                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
 798                 goto out3;
 799         }
 800
 801         if (!request_region(HD_DATA + 6, 1, "hd"))
 802         {
 803                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
 804                 goto out4;
 805         }
 806
 807         if (!request_region(HD_DATA + 8, 1, "hd"))
 808         {
 809                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
 810                 goto out5;
 811         }
 812
 813         if (!request_region(HD_DATA + 10, 1, "hd"))
 814         {
 815                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
 816                 goto out6;
 817         }
 818
 819         if (!request_region(HD_DATA + 12, 1, "hd"))
 820         {
 821                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
 822                 goto out7;
 823         }
 824
 825         if (!request_region(HD_CMD, 1, "hd(cmd)"))
 826         {
 827                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_CMD);
 828                 goto out8;
 829         }
 830
 831         if (!request_region(HD_CMD + 2, 1, "hd(cmd)"))
 832         {
 833                 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_CMD);
 834                 goto out9;
 835         }
 836
 837         for(drive=0; drive < NR_HD; drive++)
 838                 add_disk(hd_gendisk[drive]);
 839         return 0;
 840
 841 out9:
 842         release_region(HD_CMD, 1);
 843 out8:
 844         release_region(HD_DATA + 12, 1);
 845 out7:
 846         release_region(HD_DATA + 10, 1);
 847 out6:
 848         release_region(HD_DATA + 8, 1);
 849 out5:
 850         release_region(HD_DATA + 6, 1);
 851 out4:
 852         release_region(HD_DATA + 4, 1);
 853 out3:
 854         release_region(HD_DATA + 2, 1);
 855 out2:
 856         release_region(HD_DATA, 2);
 857         free_irq(HD_IRQ, NULL);
 858 out1:
 859         for (drive = 0; drive < NR_HD; drive++)
 860                 put_disk(hd_gendisk[drive]);
 861         NR_HD = 0;
 862 out:
 863         del_timer(&device_timer);
 864         unregister_blkdev(HD_MAJOR,"hd");
 865         blk_cleanup_queue(hd_queue);
 866         return -1;
 867 Enomem:
 868         while (drive--)
 869                 put_disk(hd_gendisk[drive]);
 870         goto out;
 871 }
 872
 873 static int parse_hd_setup (char *line) {
 874         int ints[6];
 875
 876         (void) get_options(line, ARRAY_SIZE(ints), ints);
 877         hd_setup(NULL, ints);
 878
 879         return 1;
 880 }
 881 __setup("hd=", parse_hd_setup);
 882
 883 module_init(hd_init);