git.oblomov.eu Git - linux-2.6/blob - drivers/block/amiflop.c

   1 /*
   2  *  linux/amiga/amiflop.c
   3  *
   4  *  Copyright (C) 1993  Greg Harp
   5  *  Portions of this driver are based on code contributed by Brad Pepers
   6  *
   7  *  revised 28.5.95 by Joerg Dorchain
   8  *  - now no bugs(?) any more for both HD & DD
   9  *  - added support for 40 Track 5.25" drives, 80-track hopefully behaves
  10  *    like 3.5" dd (no way to test - are there any 5.25" drives out there
  11  *    that work on an A4000?)
  12  *  - wrote formatting routine (maybe dirty, but works)
  13  *
  14  *  june/july 1995 added ms-dos support by Joerg Dorchain
  15  *  (portions based on messydos.device and various contributors)
  16  *  - currently only 9 and 18 sector disks
  17  *
  18  *  - fixed a bug with the internal trackbuffer when using multiple
  19  *    disks the same time
  20  *  - made formatting a bit safer
  21  *  - added command line and machine based default for "silent" df0
  22  *
  23  *  december 1995 adapted for 1.2.13pl4 by Joerg Dorchain
  24  *  - works but I think it's inefficient. (look in redo_fd_request)
  25  *    But the changes were very efficient. (only three and a half lines)
  26  *
  27  *  january 1996 added special ioctl for tracking down read/write problems
  28  *  - usage ioctl(d, RAW_TRACK, ptr); the raw track buffer (MFM-encoded data
  29  *    is copied to area. (area should be large enough since no checking is
  30  *    done - 30K is currently sufficient). return the actual size of the
  31  *    trackbuffer
  32  *  - replaced udelays() by a timer (CIAA timer B) for the waits
  33  *    needed for the disk mechanic.
  34  *
  35  *  february 1996 fixed error recovery and multiple disk access
  36  *  - both got broken the first time I tampered with the driver :-(
  37  *  - still not safe, but better than before
  38  *
  39  *  revised Marts 3rd, 1996 by Jes Sorensen for use in the 1.3.28 kernel.
  40  *  - Minor changes to accept the kdev_t.
  41  *  - Replaced some more udelays with ms_delays. Udelay is just a loop,
  42  *    and so the delay will be different depending on the given
  43  *    processor :-(
  44  *  - The driver could use a major cleanup because of the new
  45  *    major/minor handling that came with kdev_t. It seems to work for
  46  *    the time being, but I can't guarantee that it will stay like
  47  *    that when we start using 16 (24?) bit minors.
  48  *
  49  * restructured jan 1997 by Joerg Dorchain
  50  * - Fixed Bug accessing multiple disks
  51  * - some code cleanup
  52  * - added trackbuffer for each drive to speed things up
  53  * - fixed some race conditions (who finds the next may send it to me ;-)
  54  */
  55
  56 #include <linux/module.h>
  57
  58 #include <linux/fd.h>
  59 #include <linux/hdreg.h>
  60 #include <linux/delay.h>
  61 #include <linux/init.h>
  62 #include <linux/amifdreg.h>
  63 #include <linux/amifd.h>
  64 #include <linux/buffer_head.h>
  65 #include <linux/blkdev.h>
  66 #include <linux/elevator.h>
  67
  68 #include <asm/setup.h>
  69 #include <asm/uaccess.h>
  70 #include <asm/amigahw.h>
  71 #include <asm/amigaints.h>
  72 #include <asm/irq.h>
  73
  74 #undef DEBUG /* print _LOTS_ of infos */
  75
  76 #define RAW_IOCTL
  77 #ifdef RAW_IOCTL
  78 #define IOCTL_RAW_TRACK 0x5254524B  /* 'RTRK' */
  79 #endif
  80
  81 /*
  82  *  Defines
  83  */
  84
  85 /*
  86  *  Error codes
  87  */
  88 #define FD_OK           0       /* operation succeeded */
  89 #define FD_ERROR        -1      /* general error (seek, read, write, etc) */
  90 #define FD_NOUNIT       1       /* unit does not exist */
  91 #define FD_UNITBUSY     2       /* unit already active */
  92 #define FD_NOTACTIVE    3       /* unit is not active */
  93 #define FD_NOTREADY     4       /* unit is not ready (motor not on/no disk) */
  94
  95 #define MFM_NOSYNC      1
  96 #define MFM_HEADER      2
  97 #define MFM_DATA        3
  98 #define MFM_TRACK       4
  99
 100 /*
 101  *  Floppy ID values
 102  */
 103 #define FD_NODRIVE      0x00000000  /* response when no unit is present */
 104 #define FD_DD_3         0xffffffff  /* double-density 3.5" (880K) drive */
 105 #define FD_HD_3         0x55555555  /* high-density 3.5" (1760K) drive */
 106 #define FD_DD_5         0xaaaaaaaa  /* double-density 5.25" (440K) drive */
 107
 108 static unsigned long int fd_def_df0 = FD_DD_3;     /* default for df0 if it doesn't identify */
 109
 110 module_param(fd_def_df0, ulong, 0);
 111 MODULE_LICENSE("GPL");
 112
 113 static struct request_queue *floppy_queue;
 114 #define QUEUE (floppy_queue)
 115 #define CURRENT elv_next_request(floppy_queue)
 116
 117 /*
 118  *  Macros
 119  */
 120 #define MOTOR_ON        (ciab.prb &= ~DSKMOTOR)
 121 #define MOTOR_OFF       (ciab.prb |= DSKMOTOR)
 122 #define SELECT(mask)    (ciab.prb &= ~mask)
 123 #define DESELECT(mask)  (ciab.prb |= mask)
 124 #define SELMASK(drive)  (1 << (3 + (drive & 3)))
 125
 126 static struct fd_drive_type drive_types[] = {
 127 /*  code        name       tr he   rdsz   wrsz sm pc1 pc2 sd  st st*/
 128 /*  warning: times are now in milliseconds (ms)                    */
 129 { FD_DD_3,      "DD 3.5",  80, 2, 14716, 13630, 1, 80,161, 3, 18, 1},
 130 { FD_HD_3,      "HD 3.5",  80, 2, 28344, 27258, 2, 80,161, 3, 18, 1},
 131 { FD_DD_5,      "DD 5.25", 40, 2, 14716, 13630, 1, 40, 81, 6, 30, 2},
 132 { FD_NODRIVE, "No Drive", 0, 0,     0,     0, 0,  0,  0,  0,  0, 0}
 133 };
 134 static int num_dr_types = sizeof(drive_types) / sizeof(drive_types[0]);
 135
 136 static int amiga_read(int), dos_read(int);
 137 static void amiga_write(int), dos_write(int);
 138 static struct fd_data_type data_types[] = {
 139         { "Amiga", 11 , amiga_read, amiga_write},
 140         { "MS-Dos", 9, dos_read, dos_write}
 141 };
 142
 143 /* current info on each unit */
 144 static struct amiga_floppy_struct unit[FD_MAX_UNITS];
 145
 146 static struct timer_list flush_track_timer[FD_MAX_UNITS];
 147 static struct timer_list post_write_timer;
 148 static struct timer_list motor_on_timer;
 149 static struct timer_list motor_off_timer[FD_MAX_UNITS];
 150 static int on_attempts;
 151
 152 /* Synchronization of FDC access */
 153 /* request loop (trackbuffer) */
 154 static volatile int fdc_busy = -1;
 155 static volatile int fdc_nested;
 156 static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
 157
 158 static DECLARE_WAIT_QUEUE_HEAD(motor_wait);
 159
 160 static volatile int selected = -1;      /* currently selected drive */
 161
 162 static int writepending;
 163 static int writefromint;
 164 static char *raw_buf;
 165
 166 static DEFINE_SPINLOCK(amiflop_lock);
 167
 168 #define RAW_BUF_SIZE 30000  /* size of raw disk data */
 169
 170 /*
 171  * These are global variables, as that's the easiest way to give
 172  * information to interrupts. They are the data used for the current
 173  * request.
 174  */
 175 static volatile char block_flag;
 176 static DECLARE_WAIT_QUEUE_HEAD(wait_fd_block);
 177
 178 /* MS-Dos MFM Coding tables (should go quick and easy) */
 179 static unsigned char mfmencode[16]={
 180         0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15,
 181         0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55
 182 };
 183 static unsigned char mfmdecode[128];
 184
 185 /* floppy internal millisecond timer stuff */
 186 static volatile int ms_busy = -1;
 187 static DECLARE_WAIT_QUEUE_HEAD(ms_wait);
 188 #define MS_TICKS ((amiga_eclock+50)/1000)
 189
 190 /*
 191  * Note that MAX_ERRORS=X doesn't imply that we retry every bad read
 192  * max X times - some types of errors increase the errorcount by 2 or
 193  * even 3, so we might actually retry only X/2 times before giving up.
 194  */
 195 #define MAX_ERRORS 12
 196
 197 /* Prevent "aliased" accesses. */
 198 static int fd_ref[4] = { 0,0,0,0 };
 199 static int fd_device[4] = { 0, 0, 0, 0 };
 200
 201 /*
 202  * Here come the actual hardware access and helper functions.
 203  * They are not reentrant and single threaded because all drives
 204  * share the same hardware and the same trackbuffer.
 205  */
 206
 207 /* Milliseconds timer */
 208
 209 static irqreturn_t ms_isr(int irq, void *dummy, struct pt_regs *fp)
 210 {
 211         ms_busy = -1;
 212         wake_up(&ms_wait);
 213         return IRQ_HANDLED;
 214 }
 215
 216 /* all waits are queued up
 217    A more generic routine would do a schedule a la timer.device */
 218 static void ms_delay(int ms)
 219 {
 220         unsigned long flags;
 221         int ticks;
 222         if (ms > 0) {
 223                 local_irq_save(flags);
 224                 while (ms_busy == 0)
 225                         sleep_on(&ms_wait);
 226                 ms_busy = 0;
 227                 local_irq_restore(flags);
 228                 ticks = MS_TICKS*ms-1;
 229                 ciaa.tblo=ticks%256;
 230                 ciaa.tbhi=ticks/256;
 231                 ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */
 232                 sleep_on(&ms_wait);
 233         }
 234 }
 235
 236 /* Hardware semaphore */
 237
 238 /* returns true when we would get the semaphore */
 239 static inline int try_fdc(int drive)
 240 {
 241         drive &= 3;
 242         return ((fdc_busy < 0) || (fdc_busy == drive));
 243 }
 244
 245 static void get_fdc(int drive)
 246 {
 247         unsigned long flags;
 248
 249         drive &= 3;
 250 #ifdef DEBUG
 251         printk("get_fdc: drive %d  fdc_busy %d  fdc_nested %d\n",drive,fdc_busy,fdc_nested);
 252 #endif
 253         local_irq_save(flags);
 254         while (!try_fdc(drive))
 255                 sleep_on(&fdc_wait);
 256         fdc_busy = drive;
 257         fdc_nested++;
 258         local_irq_restore(flags);
 259 }
 260
 261 static inline void rel_fdc(void)
 262 {
 263 #ifdef DEBUG
 264         if (fdc_nested == 0)
 265                 printk("fd: unmatched rel_fdc\n");
 266         printk("rel_fdc: fdc_busy %d fdc_nested %d\n",fdc_busy,fdc_nested);
 267 #endif
 268         fdc_nested--;
 269         if (fdc_nested == 0) {
 270                 fdc_busy = -1;
 271                 wake_up(&fdc_wait);
 272         }
 273 }
 274
 275 static void fd_select (int drive)
 276 {
 277         unsigned char prb = ~0;
 278
 279         drive&=3;
 280 #ifdef DEBUG
 281         printk("selecting %d\n",drive);
 282 #endif
 283         if (drive == selected)
 284                 return;
 285         get_fdc(drive);
 286         selected = drive;
 287
 288         if (unit[drive].track % 2 != 0)
 289                 prb &= ~DSKSIDE;
 290         if (unit[drive].motor == 1)
 291                 prb &= ~DSKMOTOR;
 292         ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
 293         ciab.prb = prb;
 294         prb &= ~SELMASK(drive);
 295         ciab.prb = prb;
 296         rel_fdc();
 297 }
 298
 299 static void fd_deselect (int drive)
 300 {
 301         unsigned char prb;
 302         unsigned long flags;
 303
 304         drive&=3;
 305 #ifdef DEBUG
 306         printk("deselecting %d\n",drive);
 307 #endif
 308         if (drive != selected) {
 309                 printk(KERN_WARNING "Deselecting drive %d while %d was selected!\n",drive,selected);
 310                 return;
 311         }
 312
 313         get_fdc(drive);
 314         local_irq_save(flags);
 315
 316         selected = -1;
 317
 318         prb = ciab.prb;
 319         prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
 320         ciab.prb = prb;
 321
 322         local_irq_restore (flags);
 323         rel_fdc();
 324
 325 }
 326
 327 static void motor_on_callback(unsigned long nr)
 328 {
 329         if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {
 330                 wake_up (&motor_wait);
 331         } else {
 332                 motor_on_timer.expires = jiffies + HZ/10;
 333                 add_timer(&motor_on_timer);
 334         }
 335 }
 336
 337 static int fd_motor_on(int nr)
 338 {
 339         nr &= 3;
 340
 341         del_timer(motor_off_timer + nr);
 342
 343         if (!unit[nr].motor) {
 344                 unit[nr].motor = 1;
 345                 fd_select(nr);
 346
 347                 motor_on_timer.data = nr;
 348                 mod_timer(&motor_on_timer, jiffies + HZ/2);
 349
 350                 on_attempts = 10;
 351                 sleep_on (&motor_wait);
 352                 fd_deselect(nr);
 353         }
 354
 355         if (on_attempts == 0) {
 356                 on_attempts = -1;
 357 #if 0
 358                 printk (KERN_ERR "motor_on failed, turning motor off\n");
 359                 fd_motor_off (nr);
 360                 return 0;
 361 #else
 362                 printk (KERN_WARNING "DSKRDY not set after 1.5 seconds - assuming drive is spinning notwithstanding\n");
 363 #endif
 364         }
 365
 366         return 1;
 367 }
 368
 369 static void fd_motor_off(unsigned long drive)
 370 {
 371         long calledfromint;
 372 #ifdef MODULE
 373         long decusecount;
 374
 375         decusecount = drive & 0x40000000;
 376 #endif
 377         calledfromint = drive & 0x80000000;
 378         drive&=3;
 379         if (calledfromint && !try_fdc(drive)) {
 380                 /* We would be blocked in an interrupt, so try again later */
 381                 motor_off_timer[drive].expires = jiffies + 1;
 382                 add_timer(motor_off_timer + drive);
 383                 return;
 384         }
 385         unit[drive].motor = 0;
 386         fd_select(drive);
 387         udelay (1);
 388         fd_deselect(drive);
 389 }
 390
 391 static void floppy_off (unsigned int nr)
 392 {
 393         int drive;
 394
 395         drive = nr & 3;
 396         /* called this way it is always from interrupt */
 397         motor_off_timer[drive].data = nr | 0x80000000;
 398         mod_timer(motor_off_timer + drive, jiffies + 3*HZ);
 399 }
 400
 401 static int fd_calibrate(int drive)
 402 {
 403         unsigned char prb;
 404         int n;
 405
 406         drive &= 3;
 407         get_fdc(drive);
 408         if (!fd_motor_on (drive))
 409                 return 0;
 410         fd_select (drive);
 411         prb = ciab.prb;
 412         prb |= DSKSIDE;
 413         prb &= ~DSKDIREC;
 414         ciab.prb = prb;
 415         for (n = unit[drive].type->tracks/2; n != 0; --n) {
 416                 if (ciaa.pra & DSKTRACK0)
 417                         break;
 418                 prb &= ~DSKSTEP;
 419                 ciab.prb = prb;
 420                 prb |= DSKSTEP;
 421                 udelay (2);
 422                 ciab.prb = prb;
 423                 ms_delay(unit[drive].type->step_delay);
 424         }
 425         ms_delay (unit[drive].type->settle_time);
 426         prb |= DSKDIREC;
 427         n = unit[drive].type->tracks + 20;
 428         for (;;) {
 429                 prb &= ~DSKSTEP;
 430                 ciab.prb = prb;
 431                 prb |= DSKSTEP;
 432                 udelay (2);
 433                 ciab.prb = prb;
 434                 ms_delay(unit[drive].type->step_delay + 1);
 435                 if ((ciaa.pra & DSKTRACK0) == 0)
 436                         break;
 437                 if (--n == 0) {
 438                         printk (KERN_ERR "fd%d: calibrate failed, turning motor off\n", drive);
 439                         fd_motor_off (drive);
 440                         unit[drive].track = -1;
 441                         rel_fdc();
 442                         return 0;
 443                 }
 444         }
 445         unit[drive].track = 0;
 446         ms_delay(unit[drive].type->settle_time);
 447
 448         rel_fdc();
 449         fd_deselect(drive);
 450         return 1;
 451 }
 452
 453 static int fd_seek(int drive, int track)
 454 {
 455         unsigned char prb;
 456         int cnt;
 457
 458 #ifdef DEBUG
 459         printk("seeking drive %d to track %d\n",drive,track);
 460 #endif
 461         drive &= 3;
 462         get_fdc(drive);
 463         if (unit[drive].track == track) {
 464                 rel_fdc();
 465                 return 1;
 466         }
 467         if (!fd_motor_on(drive)) {
 468                 rel_fdc();
 469                 return 0;
 470         }
 471         if (unit[drive].track < 0 && !fd_calibrate(drive)) {
 472                 rel_fdc();
 473                 return 0;
 474         }
 475
 476         fd_select (drive);
 477         cnt = unit[drive].track/2 - track/2;
 478         prb = ciab.prb;
 479         prb |= DSKSIDE | DSKDIREC;
 480         if (track % 2 != 0)
 481                 prb &= ~DSKSIDE;
 482         if (cnt < 0) {
 483                 cnt = - cnt;
 484                 prb &= ~DSKDIREC;
 485         }
 486         ciab.prb = prb;
 487         if (track % 2 != unit[drive].track % 2)
 488                 ms_delay (unit[drive].type->side_time);
 489         unit[drive].track = track;
 490         if (cnt == 0) {
 491                 rel_fdc();
 492                 fd_deselect(drive);
 493                 return 1;
 494         }
 495         do {
 496                 prb &= ~DSKSTEP;
 497                 ciab.prb = prb;
 498                 prb |= DSKSTEP;
 499                 udelay (1);
 500                 ciab.prb = prb;
 501                 ms_delay (unit[drive].type->step_delay);
 502         } while (--cnt != 0);
 503         ms_delay (unit[drive].type->settle_time);
 504
 505         rel_fdc();
 506         fd_deselect(drive);
 507         return 1;
 508 }
 509
 510 static unsigned long fd_get_drive_id(int drive)
 511 {
 512         int i;
 513         ulong id = 0;
 514
 515         drive&=3;
 516         get_fdc(drive);
 517         /* set up for ID */
 518         MOTOR_ON;
 519         udelay(2);
 520         SELECT(SELMASK(drive));
 521         udelay(2);
 522         DESELECT(SELMASK(drive));
 523         udelay(2);
 524         MOTOR_OFF;
 525         udelay(2);
 526         SELECT(SELMASK(drive));
 527         udelay(2);
 528         DESELECT(SELMASK(drive));
 529         udelay(2);
 530
 531         /* loop and read disk ID */
 532         for (i=0; i<32; i++) {
 533                 SELECT(SELMASK(drive));
 534                 udelay(2);
 535
 536                 /* read and store value of DSKRDY */
 537                 id <<= 1;
 538                 id |= (ciaa.pra & DSKRDY) ? 0 : 1;      /* cia regs are low-active! */
 539
 540                 DESELECT(SELMASK(drive));
 541         }
 542
 543         rel_fdc();
 544
 545         /*
 546          * RB: At least A500/A2000's df0: don't identify themselves.
 547          * As every (real) Amiga has at least a 3.5" DD drive as df0:
 548          * we default to that if df0: doesn't identify as a certain
 549          * type.
 550          */
 551         if(drive == 0 && id == FD_NODRIVE)
 552         {
 553                 id = fd_def_df0;
 554                 printk(KERN_NOTICE "fd: drive 0 didn't identify, setting default %08lx\n", (ulong)fd_def_df0);
 555         }
 556         /* return the ID value */
 557         return (id);
 558 }
 559
 560 static irqreturn_t fd_block_done(int irq, void *dummy, struct pt_regs *fp)
 561 {
 562         if (block_flag)
 563                 custom.dsklen = 0x4000;
 564
 565         if (block_flag == 2) { /* writing */
 566                 writepending = 2;
 567                 post_write_timer.expires = jiffies + 1; /* at least 2 ms */
 568                 post_write_timer.data = selected;
 569                 add_timer(&post_write_timer);
 570         }
 571         else {                /* reading */
 572                 block_flag = 0;
 573                 wake_up (&wait_fd_block);
 574         }
 575         return IRQ_HANDLED;
 576 }
 577
 578 static void raw_read(int drive)
 579 {
 580         drive&=3;
 581         get_fdc(drive);
 582         while (block_flag)
 583                 sleep_on(&wait_fd_block);
 584         fd_select(drive);
 585         /* setup adkcon bits correctly */
 586         custom.adkcon = ADK_MSBSYNC;
 587         custom.adkcon = ADK_SETCLR|ADK_WORDSYNC|ADK_FAST;
 588
 589         custom.dsksync = MFM_SYNC;
 590
 591         custom.dsklen = 0;
 592         custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
 593         custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
 594         custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
 595
 596         block_flag = 1;
 597
 598         while (block_flag)
 599                 sleep_on (&wait_fd_block);
 600
 601         custom.dsklen = 0;
 602         fd_deselect(drive);
 603         rel_fdc();
 604 }
 605
 606 static int raw_write(int drive)
 607 {
 608         ushort adk;
 609
 610         drive&=3;
 611         get_fdc(drive); /* corresponds to rel_fdc() in post_write() */
 612         if ((ciaa.pra & DSKPROT) == 0) {
 613                 rel_fdc();
 614                 return 0;
 615         }
 616         while (block_flag)
 617                 sleep_on(&wait_fd_block);
 618         fd_select(drive);
 619         /* clear adkcon bits */
 620         custom.adkcon = ADK_PRECOMP1|ADK_PRECOMP0|ADK_WORDSYNC|ADK_MSBSYNC;
 621         /* set appropriate adkcon bits */
 622         adk = ADK_SETCLR|ADK_FAST;
 623         if ((ulong)unit[drive].track >= unit[drive].type->precomp2)
 624                 adk |= ADK_PRECOMP1;
 625         else if ((ulong)unit[drive].track >= unit[drive].type->precomp1)
 626                 adk |= ADK_PRECOMP0;
 627         custom.adkcon = adk;
 628
 629         custom.dsklen = DSKLEN_WRITE;
 630         custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
 631         custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
 632         custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
 633
 634         block_flag = 2;
 635         return 1;
 636 }
 637
 638 /*
 639  * to be called at least 2ms after the write has finished but before any
 640  * other access to the hardware.
 641  */
 642 static void post_write (unsigned long drive)
 643 {
 644 #ifdef DEBUG
 645         printk("post_write for drive %ld\n",drive);
 646 #endif
 647         drive &= 3;
 648         custom.dsklen = 0;
 649         block_flag = 0;
 650         writepending = 0;
 651         writefromint = 0;
 652         unit[drive].dirty = 0;
 653         wake_up(&wait_fd_block);
 654         fd_deselect(drive);
 655         rel_fdc(); /* corresponds to get_fdc() in raw_write */
 656 }
 657
 658
 659 /*
 660  * The following functions are to convert the block contents into raw data
 661  * written to disk and vice versa.
 662  * (Add other formats here ;-))
 663  */
 664
 665 static unsigned long scan_sync(unsigned long raw, unsigned long end)
 666 {
 667         ushort *ptr = (ushort *)raw, *endp = (ushort *)end;
 668
 669         while (ptr < endp && *ptr++ != 0x4489)
 670                 ;
 671         if (ptr < endp) {
 672                 while (*ptr == 0x4489 && ptr < endp)
 673                         ptr++;
 674                 return (ulong)ptr;
 675         }
 676         return 0;
 677 }
 678
 679 static inline unsigned long checksum(unsigned long *addr, int len)
 680 {
 681         unsigned long csum = 0;
 682
 683         len /= sizeof(*addr);
 684         while (len-- > 0)
 685                 csum ^= *addr++;
 686         csum = ((csum>>1) & 0x55555555)  ^  (csum & 0x55555555);
 687
 688         return csum;
 689 }
 690
 691 static unsigned long decode (unsigned long *data, unsigned long *raw,
 692                              int len)
 693 {
 694         ulong *odd, *even;
 695
 696         /* convert length from bytes to longwords */
 697         len >>= 2;
 698         odd = raw;
 699         even = odd + len;
 700
 701         /* prepare return pointer */
 702         raw += len * 2;
 703
 704         do {
 705                 *data++ = ((*odd++ & 0x55555555) << 1) | (*even++ & 0x55555555);
 706         } while (--len != 0);
 707
 708         return (ulong)raw;
 709 }
 710
 711 struct header {
 712         unsigned char magic;
 713         unsigned char track;
 714         unsigned char sect;
 715         unsigned char ord;
 716         unsigned char labels[16];
 717         unsigned long hdrchk;
 718         unsigned long datachk;
 719 };
 720
 721 static int amiga_read(int drive)
 722 {
 723         unsigned long raw;
 724         unsigned long end;
 725         int scnt;
 726         unsigned long csum;
 727         struct header hdr;
 728
 729         drive&=3;
 730         raw = (long) raw_buf;
 731         end = raw + unit[drive].type->read_size;
 732
 733         for (scnt = 0;scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
 734                 if (!(raw = scan_sync(raw, end))) {
 735                         printk (KERN_INFO "can't find sync for sector %d\n", scnt);
 736                         return MFM_NOSYNC;
 737                 }
 738
 739                 raw = decode ((ulong *)&hdr.magic, (ulong *)raw, 4);
 740                 raw = decode ((ulong *)&hdr.labels, (ulong *)raw, 16);
 741                 raw = decode ((ulong *)&hdr.hdrchk, (ulong *)raw, 4);
 742                 raw = decode ((ulong *)&hdr.datachk, (ulong *)raw, 4);
 743                 csum = checksum((ulong *)&hdr,
 744                                 (char *)&hdr.hdrchk-(char *)&hdr);
 745
 746 #ifdef DEBUG
 747                 printk ("(%x,%d,%d,%d) (%lx,%lx,%lx,%lx) %lx %lx\n",
 748                         hdr.magic, hdr.track, hdr.sect, hdr.ord,
 749                         *(ulong *)&hdr.labels[0], *(ulong *)&hdr.labels[4],
 750                         *(ulong *)&hdr.labels[8], *(ulong *)&hdr.labels[12],
 751                         hdr.hdrchk, hdr.datachk);
 752 #endif
 753
 754                 if (hdr.hdrchk != csum) {
 755                         printk(KERN_INFO "MFM_HEADER: %08lx,%08lx\n", hdr.hdrchk, csum);
 756                         return MFM_HEADER;
 757                 }
 758
 759                 /* verify track */
 760                 if (hdr.track != unit[drive].track) {
 761                         printk(KERN_INFO "MFM_TRACK: %d, %d\n", hdr.track, unit[drive].track);
 762                         return MFM_TRACK;
 763                 }
 764
 765                 raw = decode ((ulong *)(unit[drive].trackbuf + hdr.sect*512),
 766                               (ulong *)raw, 512);
 767                 csum = checksum((ulong *)(unit[drive].trackbuf + hdr.sect*512), 512);
 768
 769                 if (hdr.datachk != csum) {
 770                         printk(KERN_INFO "MFM_DATA: (%x:%d:%d:%d) sc=%d %lx, %lx\n",
 771                                hdr.magic, hdr.track, hdr.sect, hdr.ord, scnt,
 772                                hdr.datachk, csum);
 773                         printk (KERN_INFO "data=(%lx,%lx,%lx,%lx)\n",
 774                                 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[0],
 775                                 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[1],
 776                                 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[2],
 777                                 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[3]);
 778                         return MFM_DATA;
 779                 }
 780         }
 781
 782         return 0;
 783 }
 784
 785 static void encode(unsigned long data, unsigned long *dest)
 786 {
 787         unsigned long data2;
 788
 789         data &= 0x55555555;
 790         data2 = data ^ 0x55555555;
 791         data |= ((data2 >> 1) | 0x80000000) & (data2 << 1);
 792
 793         if (*(dest - 1) & 0x00000001)
 794                 data &= 0x7FFFFFFF;
 795
 796         *dest = data;
 797 }
 798
 799 static void encode_block(unsigned long *dest, unsigned long *src, int len)
 800 {
 801         int cnt, to_cnt = 0;
 802         unsigned long data;
 803
 804         /* odd bits */
 805         for (cnt = 0; cnt < len / 4; cnt++) {
 806                 data = src[cnt] >> 1;
 807                 encode(data, dest + to_cnt++);
 808         }
 809
 810         /* even bits */
 811         for (cnt = 0; cnt < len / 4; cnt++) {
 812                 data = src[cnt];
 813                 encode(data, dest + to_cnt++);
 814         }
 815 }
 816
 817 static unsigned long *putsec(int disk, unsigned long *raw, int cnt)
 818 {
 819         struct header hdr;
 820         int i;
 821
 822         disk&=3;
 823         *raw = (raw[-1]&1) ? 0x2AAAAAAA : 0xAAAAAAAA;
 824         raw++;
 825         *raw++ = 0x44894489;
 826
 827         hdr.magic = 0xFF;
 828         hdr.track = unit[disk].track;
 829         hdr.sect = cnt;
 830         hdr.ord = unit[disk].dtype->sects * unit[disk].type->sect_mult - cnt;
 831         for (i = 0; i < 16; i++)
 832                 hdr.labels[i] = 0;
 833         hdr.hdrchk = checksum((ulong *)&hdr,
 834                               (char *)&hdr.hdrchk-(char *)&hdr);
 835         hdr.datachk = checksum((ulong *)(unit[disk].trackbuf+cnt*512), 512);
 836
 837         encode_block(raw, (ulong *)&hdr.magic, 4);
 838         raw += 2;
 839         encode_block(raw, (ulong *)&hdr.labels, 16);
 840         raw += 8;
 841         encode_block(raw, (ulong *)&hdr.hdrchk, 4);
 842         raw += 2;
 843         encode_block(raw, (ulong *)&hdr.datachk, 4);
 844         raw += 2;
 845         encode_block(raw, (ulong *)(unit[disk].trackbuf+cnt*512), 512);
 846         raw += 256;
 847
 848         return raw;
 849 }
 850
 851 static void amiga_write(int disk)
 852 {
 853         unsigned int cnt;
 854         unsigned long *ptr = (unsigned long *)raw_buf;
 855
 856         disk&=3;
 857         /* gap space */
 858         for (cnt = 0; cnt < 415 * unit[disk].type->sect_mult; cnt++)
 859                 *ptr++ = 0xaaaaaaaa;
 860
 861         /* sectors */
 862         for (cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
 863                 ptr = putsec (disk, ptr, cnt);
 864         *(ushort *)ptr = (ptr[-1]&1) ? 0x2AA8 : 0xAAA8;
 865 }
 866
 867
 868 struct dos_header {
 869         unsigned char track,   /* 0-80 */
 870                 side,    /* 0-1 */
 871                 sec,     /* 0-...*/
 872                 len_desc;/* 2 */
 873         unsigned short crc;     /* on 68000 we got an alignment problem,
 874                                    but this compiler solves it  by adding silently
 875                                    adding a pad byte so data won't fit
 876                                    and this took about 3h to discover.... */
 877         unsigned char gap1[22];     /* for longword-alignedness (0x4e) */
 878 };
 879
 880 /* crc routines are borrowed from the messydos-handler  */
 881
 882 /* excerpt from the messydos-device
 883 ; The CRC is computed not only over the actual data, but including
 884 ; the SYNC mark (3 * $a1) and the 'ID/DATA - Address Mark' ($fe/$fb).
 885 ; As we don't read or encode these fields into our buffers, we have to
 886 ; preload the registers containing the CRC with the values they would have
 887 ; after stepping over these fields.
 888 ;
 889 ; How CRCs "really" work:
 890 ;
 891 ; First, you should regard a bitstring as a series of coefficients of
 892 ; polynomials. We calculate with these polynomials in modulo-2
 893 ; arithmetic, in which both add and subtract are done the same as
 894 ; exclusive-or. Now, we modify our data (a very long polynomial) in
 895 ; such a way that it becomes divisible by the CCITT-standard 16-bit
 896 ;                16   12   5
 897 ; polynomial:   x  + x  + x + 1, represented by $11021. The easiest
 898 ; way to do this would be to multiply (using proper arithmetic) our
 899 ; datablock with $11021. So we have:
 900 ;   data * $11021                =
 901 ;   data * ($10000 + $1021)      =
 902 ;   data * $10000 + data * $1021
 903 ; The left part of this is simple: Just add two 0 bytes. But then
 904 ; the right part (data $1021) remains difficult and even could have
 905 ; a carry into the left part. The solution is to use a modified
 906 ; multiplication, which has a result that is not correct, but with
 907 ; a difference of any multiple of $11021. We then only need to keep
 908 ; the 16 least significant bits of the result.
 909 ;
 910 ; The following algorithm does this for us:
 911 ;
 912 ;   unsigned char *data, c, crclo, crchi;
 913 ;   while (not done) {
 914 ;       c = *data++ + crchi;
 915 ;       crchi = (@ c) >> 8 + crclo;
 916 ;       crclo = @ c;
 917 ;   }
 918 ;
 919 ; Remember, + is done with EOR, the @ operator is in two tables (high
 920 ; and low byte separately), which is calculated as
 921 ;
 922 ;      $1021 * (c & $F0)
 923 ;  xor $1021 * (c & $0F)
 924 ;  xor $1021 * (c >> 4)         (* is regular multiplication)
 925 ;
 926 ;
 927 ; Anyway, the end result is the same as the remainder of the division of
 928 ; the data by $11021. I am afraid I need to study theory a bit more...
 929
 930
 931 my only works was to code this from manx to C....
 932
 933 */
 934
 935 static ushort dos_crc(void * data_a3, int data_d0, int data_d1, int data_d3)
 936 {
 937         static unsigned char CRCTable1[] = {
 938                 0x00,0x10,0x20,0x30,0x40,0x50,0x60,0x70,0x81,0x91,0xa1,0xb1,0xc1,0xd1,0xe1,0xf1,
 939                 0x12,0x02,0x32,0x22,0x52,0x42,0x72,0x62,0x93,0x83,0xb3,0xa3,0xd3,0xc3,0xf3,0xe3,
 940                 0x24,0x34,0x04,0x14,0x64,0x74,0x44,0x54,0xa5,0xb5,0x85,0x95,0xe5,0xf5,0xc5,0xd5,
 941                 0x36,0x26,0x16,0x06,0x76,0x66,0x56,0x46,0xb7,0xa7,0x97,0x87,0xf7,0xe7,0xd7,0xc7,
 942                 0x48,0x58,0x68,0x78,0x08,0x18,0x28,0x38,0xc9,0xd9,0xe9,0xf9,0x89,0x99,0xa9,0xb9,
 943                 0x5a,0x4a,0x7a,0x6a,0x1a,0x0a,0x3a,0x2a,0xdb,0xcb,0xfb,0xeb,0x9b,0x8b,0xbb,0xab,
 944                 0x6c,0x7c,0x4c,0x5c,0x2c,0x3c,0x0c,0x1c,0xed,0xfd,0xcd,0xdd,0xad,0xbd,0x8d,0x9d,
 945                 0x7e,0x6e,0x5e,0x4e,0x3e,0x2e,0x1e,0x0e,0xff,0xef,0xdf,0xcf,0xbf,0xaf,0x9f,0x8f,
 946                 0x91,0x81,0xb1,0xa1,0xd1,0xc1,0xf1,0xe1,0x10,0x00,0x30,0x20,0x50,0x40,0x70,0x60,
 947                 0x83,0x93,0xa3,0xb3,0xc3,0xd3,0xe3,0xf3,0x02,0x12,0x22,0x32,0x42,0x52,0x62,0x72,
 948                 0xb5,0xa5,0x95,0x85,0xf5,0xe5,0xd5,0xc5,0x34,0x24,0x14,0x04,0x74,0x64,0x54,0x44,
 949                 0xa7,0xb7,0x87,0x97,0xe7,0xf7,0xc7,0xd7,0x26,0x36,0x06,0x16,0x66,0x76,0x46,0x56,
 950                 0xd9,0xc9,0xf9,0xe9,0x99,0x89,0xb9,0xa9,0x58,0x48,0x78,0x68,0x18,0x08,0x38,0x28,
 951                 0xcb,0xdb,0xeb,0xfb,0x8b,0x9b,0xab,0xbb,0x4a,0x5a,0x6a,0x7a,0x0a,0x1a,0x2a,0x3a,
 952                 0xfd,0xed,0xdd,0xcd,0xbd,0xad,0x9d,0x8d,0x7c,0x6c,0x5c,0x4c,0x3c,0x2c,0x1c,0x0c,
 953                 0xef,0xff,0xcf,0xdf,0xaf,0xbf,0x8f,0x9f,0x6e,0x7e,0x4e,0x5e,0x2e,0x3e,0x0e,0x1e
 954         };
 955
 956         static unsigned char CRCTable2[] = {
 957                 0x00,0x21,0x42,0x63,0x84,0xa5,0xc6,0xe7,0x08,0x29,0x4a,0x6b,0x8c,0xad,0xce,0xef,
 958                 0x31,0x10,0x73,0x52,0xb5,0x94,0xf7,0xd6,0x39,0x18,0x7b,0x5a,0xbd,0x9c,0xff,0xde,
 959                 0x62,0x43,0x20,0x01,0xe6,0xc7,0xa4,0x85,0x6a,0x4b,0x28,0x09,0xee,0xcf,0xac,0x8d,
 960                 0x53,0x72,0x11,0x30,0xd7,0xf6,0x95,0xb4,0x5b,0x7a,0x19,0x38,0xdf,0xfe,0x9d,0xbc,
 961                 0xc4,0xe5,0x86,0xa7,0x40,0x61,0x02,0x23,0xcc,0xed,0x8e,0xaf,0x48,0x69,0x0a,0x2b,
 962                 0xf5,0xd4,0xb7,0x96,0x71,0x50,0x33,0x12,0xfd,0xdc,0xbf,0x9e,0x79,0x58,0x3b,0x1a,
 963                 0xa6,0x87,0xe4,0xc5,0x22,0x03,0x60,0x41,0xae,0x8f,0xec,0xcd,0x2a,0x0b,0x68,0x49,
 964                 0x97,0xb6,0xd5,0xf4,0x13,0x32,0x51,0x70,0x9f,0xbe,0xdd,0xfc,0x1b,0x3a,0x59,0x78,
 965                 0x88,0xa9,0xca,0xeb,0x0c,0x2d,0x4e,0x6f,0x80,0xa1,0xc2,0xe3,0x04,0x25,0x46,0x67,
 966                 0xb9,0x98,0xfb,0xda,0x3d,0x1c,0x7f,0x5e,0xb1,0x90,0xf3,0xd2,0x35,0x14,0x77,0x56,
 967                 0xea,0xcb,0xa8,0x89,0x6e,0x4f,0x2c,0x0d,0xe2,0xc3,0xa0,0x81,0x66,0x47,0x24,0x05,
 968                 0xdb,0xfa,0x99,0xb8,0x5f,0x7e,0x1d,0x3c,0xd3,0xf2,0x91,0xb0,0x57,0x76,0x15,0x34,
 969                 0x4c,0x6d,0x0e,0x2f,0xc8,0xe9,0x8a,0xab,0x44,0x65,0x06,0x27,0xc0,0xe1,0x82,0xa3,
 970                 0x7d,0x5c,0x3f,0x1e,0xf9,0xd8,0xbb,0x9a,0x75,0x54,0x37,0x16,0xf1,0xd0,0xb3,0x92,
 971                 0x2e,0x0f,0x6c,0x4d,0xaa,0x8b,0xe8,0xc9,0x26,0x07,0x64,0x45,0xa2,0x83,0xe0,0xc1,
 972                 0x1f,0x3e,0x5d,0x7c,0x9b,0xba,0xd9,0xf8,0x17,0x36,0x55,0x74,0x93,0xb2,0xd1,0xf0
 973         };
 974
 975 /* look at the asm-code - what looks in C a bit strange is almost as good as handmade */
 976         register int i;
 977         register unsigned char *CRCT1, *CRCT2, *data, c, crch, crcl;
 978
 979         CRCT1=CRCTable1;
 980         CRCT2=CRCTable2;
 981         data=data_a3;
 982         crcl=data_d1;
 983         crch=data_d0;
 984         for (i=data_d3; i>=0; i--) {
 985                 c = (*data++) ^ crch;
 986                 crch = CRCT1[c] ^ crcl;
 987                 crcl = CRCT2[c];
 988         }
 989         return (crch<<8)|crcl;
 990 }
 991
 992 static inline ushort dos_hdr_crc (struct dos_header *hdr)
 993 {
 994         return dos_crc(&(hdr->track), 0xb2, 0x30, 3); /* precomputed magic */
 995 }
 996
 997 static inline ushort dos_data_crc(unsigned char *data)
 998 {
 999         return dos_crc(data, 0xe2, 0x95 ,511); /* precomputed magic */
1000 }
1001
1002 static inline unsigned char dos_decode_byte(ushort word)
1003 {
1004         register ushort w2;
1005         register unsigned char byte;
1006         register unsigned char *dec = mfmdecode;
1007
1008         w2=word;
1009         w2>>=8;
1010         w2&=127;
1011         byte = dec[w2];
1012         byte <<= 4;
1013         w2 = word & 127;
1014         byte |= dec[w2];
1015         return byte;
1016 }
1017
1018 static unsigned long dos_decode(unsigned char *data, unsigned short *raw, int len)
1019 {
1020         int i;
1021
1022         for (i = 0; i < len; i++)
1023                 *data++=dos_decode_byte(*raw++);
1024         return ((ulong)raw);
1025 }
1026
1027 #ifdef DEBUG
1028 static void dbg(unsigned long ptr)
1029 {
1030         printk("raw data @%08lx: %08lx, %08lx ,%08lx, %08lx\n", ptr,
1031                ((ulong *)ptr)[0], ((ulong *)ptr)[1],
1032                ((ulong *)ptr)[2], ((ulong *)ptr)[3]);
1033 }
1034 #endif
1035
1036 static int dos_read(int drive)
1037 {
1038         unsigned long end;
1039         unsigned long raw;
1040         int scnt;
1041         unsigned short crc,data_crc[2];
1042         struct dos_header hdr;
1043
1044         drive&=3;
1045         raw = (long) raw_buf;
1046         end = raw + unit[drive].type->read_size;
1047
1048         for (scnt=0; scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
1049                 do { /* search for the right sync of each sec-hdr */
1050                         if (!(raw = scan_sync (raw, end))) {
1051                                 printk(KERN_INFO "dos_read: no hdr sync on "
1052                                        "track %d, unit %d for sector %d\n",
1053                                        unit[drive].track,drive,scnt);
1054                                 return MFM_NOSYNC;
1055                         }
1056 #ifdef DEBUG
1057                         dbg(raw);
1058 #endif
1059                 } while (*((ushort *)raw)!=0x5554); /* loop usually only once done */
1060                 raw+=2; /* skip over headermark */
1061                 raw = dos_decode((unsigned char *)&hdr,(ushort *) raw,8);
1062                 crc = dos_hdr_crc(&hdr);
1063
1064 #ifdef DEBUG
1065                 printk("(%3d,%d,%2d,%d) %x\n", hdr.track, hdr.side,
1066                        hdr.sec, hdr.len_desc, hdr.crc);
1067 #endif
1068
1069                 if (crc != hdr.crc) {
1070                         printk(KERN_INFO "dos_read: MFM_HEADER %04x,%04x\n",
1071                                hdr.crc, crc);
1072                         return MFM_HEADER;
1073                 }
1074                 if (hdr.track != unit[drive].track/unit[drive].type->heads) {
1075                         printk(KERN_INFO "dos_read: MFM_TRACK %d, %d\n",
1076                                hdr.track,
1077                                unit[drive].track/unit[drive].type->heads);
1078                         return MFM_TRACK;
1079                 }
1080
1081                 if (hdr.side != unit[drive].track%unit[drive].type->heads) {
1082                         printk(KERN_INFO "dos_read: MFM_SIDE %d, %d\n",
1083                                hdr.side,
1084                                unit[drive].track%unit[drive].type->heads);
1085                         return MFM_TRACK;
1086                 }
1087
1088                 if (hdr.len_desc != 2) {
1089                         printk(KERN_INFO "dos_read: unknown sector len "
1090                                "descriptor %d\n", hdr.len_desc);
1091                         return MFM_DATA;
1092                 }
1093 #ifdef DEBUG
1094                 printk("hdr accepted\n");
1095 #endif
1096                 if (!(raw = scan_sync (raw, end))) {
1097                         printk(KERN_INFO "dos_read: no data sync on track "
1098                                "%d, unit %d for sector%d, disk sector %d\n",
1099                                unit[drive].track, drive, scnt, hdr.sec);
1100                         return MFM_NOSYNC;
1101                 }
1102 #ifdef DEBUG
1103                 dbg(raw);
1104 #endif
1105
1106                 if (*((ushort *)raw)!=0x5545) {
1107                         printk(KERN_INFO "dos_read: no data mark after "
1108                                "sync (%d,%d,%d,%d) sc=%d\n",
1109                                hdr.track,hdr.side,hdr.sec,hdr.len_desc,scnt);
1110                         return MFM_NOSYNC;
1111                 }
1112
1113                 raw+=2;  /* skip data mark (included in checksum) */
1114                 raw = dos_decode((unsigned char *)(unit[drive].trackbuf + (hdr.sec - 1) * 512), (ushort *) raw, 512);
1115                 raw = dos_decode((unsigned char  *)data_crc,(ushort *) raw,4);
1116                 crc = dos_data_crc(unit[drive].trackbuf + (hdr.sec - 1) * 512);
1117
1118                 if (crc != data_crc[0]) {
1119                         printk(KERN_INFO "dos_read: MFM_DATA (%d,%d,%d,%d) "
1120                                "sc=%d, %x %x\n", hdr.track, hdr.side,
1121                                hdr.sec, hdr.len_desc, scnt,data_crc[0], crc);
1122                         printk(KERN_INFO "data=(%lx,%lx,%lx,%lx,...)\n",
1123                                ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[0],
1124                                ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[1],
1125                                ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[2],
1126                                ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[3]);
1127                         return MFM_DATA;
1128                 }
1129         }
1130         return 0;
1131 }
1132
1133 static inline ushort dos_encode_byte(unsigned char byte)
1134 {
1135         register unsigned char *enc, b2, b1;
1136         register ushort word;
1137
1138         enc=mfmencode;
1139         b1=byte;
1140         b2=b1>>4;
1141         b1&=15;
1142         word=enc[b2] <<8 | enc [b1];
1143         return (word|((word&(256|64)) ? 0: 128));
1144 }
1145
1146 static void dos_encode_block(ushort *dest, unsigned char *src, int len)
1147 {
1148         int i;
1149
1150         for (i = 0; i < len; i++) {
1151                 *dest=dos_encode_byte(*src++);
1152                 *dest|=((dest[-1]&1)||(*dest&0x4000))? 0: 0x8000;
1153                 dest++;
1154         }
1155 }
1156
1157 static unsigned long *ms_putsec(int drive, unsigned long *raw, int cnt)
1158 {
1159         static struct dos_header hdr={0,0,0,2,0,
1160           {78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78}};
1161         int i;
1162         static ushort crc[2]={0,0x4e4e};
1163
1164         drive&=3;
1165 /* id gap 1 */
1166 /* the MFM word before is always 9254 */
1167         for(i=0;i<6;i++)
1168                 *raw++=0xaaaaaaaa;
1169 /* 3 sync + 1 headermark */
1170         *raw++=0x44894489;
1171         *raw++=0x44895554;
1172
1173 /* fill in the variable parts of the header */
1174         hdr.track=unit[drive].track/unit[drive].type->heads;
1175         hdr.side=unit[drive].track%unit[drive].type->heads;
1176         hdr.sec=cnt+1;
1177         hdr.crc=dos_hdr_crc(&hdr);
1178
1179 /* header (without "magic") and id gap 2*/
1180         dos_encode_block((ushort *)raw,(unsigned char *) &hdr.track,28);
1181         raw+=14;
1182
1183 /*id gap 3 */
1184         for(i=0;i<6;i++)
1185                 *raw++=0xaaaaaaaa;
1186
1187 /* 3 syncs and 1 datamark */
1188         *raw++=0x44894489;
1189         *raw++=0x44895545;
1190
1191 /* data */
1192         dos_encode_block((ushort *)raw,
1193                          (unsigned char *)unit[drive].trackbuf+cnt*512,512);
1194         raw+=256;
1195
1196 /*data crc + jd's special gap (long words :-/) */
1197         crc[0]=dos_data_crc(unit[drive].trackbuf+cnt*512);
1198         dos_encode_block((ushort *) raw,(unsigned char *)crc,4);
1199         raw+=2;
1200
1201 /* data gap */
1202         for(i=0;i<38;i++)
1203                 *raw++=0x92549254;
1204
1205         return raw; /* wrote 652 MFM words */
1206 }
1207
1208 static void dos_write(int disk)
1209 {
1210         int cnt;
1211         unsigned long raw = (unsigned long) raw_buf;
1212         unsigned long *ptr=(unsigned long *)raw;
1213
1214         disk&=3;
1215 /* really gap4 + indexgap , but we write it first and round it up */
1216         for (cnt=0;cnt<425;cnt++)
1217                 *ptr++=0x92549254;
1218
1219 /* the following is just guessed */
1220         if (unit[disk].type->sect_mult==2)  /* check for HD-Disks */
1221                 for(cnt=0;cnt<473;cnt++)
1222                         *ptr++=0x92549254;
1223
1224 /* now the index marks...*/
1225         for (cnt=0;cnt<20;cnt++)
1226                 *ptr++=0x92549254;
1227         for (cnt=0;cnt<6;cnt++)
1228                 *ptr++=0xaaaaaaaa;
1229         *ptr++=0x52245224;
1230         *ptr++=0x52245552;
1231         for (cnt=0;cnt<20;cnt++)
1232                 *ptr++=0x92549254;
1233
1234 /* sectors */
1235         for(cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
1236                 ptr=ms_putsec(disk,ptr,cnt);
1237
1238         *(ushort *)ptr = 0xaaa8; /* MFM word before is always 0x9254 */
1239 }
1240
1241 /*
1242  * Here comes the high level stuff (i.e. the filesystem interface)
1243  * and helper functions.
1244  * Normally this should be the only part that has to be adapted to
1245  * different kernel versions.
1246  */
1247
1248 /* FIXME: this assumes the drive is still spinning -
1249  * which is only true if we complete writing a track within three seconds
1250  */
1251 static void flush_track_callback(unsigned long nr)
1252 {
1253         nr&=3;
1254         writefromint = 1;
1255         if (!try_fdc(nr)) {
1256                 /* we might block in an interrupt, so try again later */
1257                 flush_track_timer[nr].expires = jiffies + 1;
1258                 add_timer(flush_track_timer + nr);
1259                 return;
1260         }
1261         get_fdc(nr);
1262         (*unit[nr].dtype->write_fkt)(nr);
1263         if (!raw_write(nr)) {
1264                 printk (KERN_NOTICE "floppy disk write protected\n");
1265                 writefromint = 0;
1266                 writepending = 0;
1267         }
1268         rel_fdc();
1269 }
1270
1271 static int non_int_flush_track (unsigned long nr)
1272 {
1273         unsigned long flags;
1274
1275         nr&=3;
1276         writefromint = 0;
1277         del_timer(&post_write_timer);
1278         get_fdc(nr);
1279         if (!fd_motor_on(nr)) {
1280                 writepending = 0;
1281                 rel_fdc();
1282                 return 0;
1283         }
1284         local_irq_save(flags);
1285         if (writepending != 2) {
1286                 local_irq_restore(flags);
1287                 (*unit[nr].dtype->write_fkt)(nr);
1288                 if (!raw_write(nr)) {
1289                         printk (KERN_NOTICE "floppy disk write protected "
1290                                 "in write!\n");
1291                         writepending = 0;
1292                         return 0;
1293                 }
1294                 while (block_flag == 2)
1295                         sleep_on (&wait_fd_block);
1296         }
1297         else {
1298                 local_irq_restore(flags);
1299                 ms_delay(2); /* 2 ms post_write delay */
1300                 post_write(nr);
1301         }
1302         rel_fdc();
1303         return 1;
1304 }
1305
1306 static int get_track(int drive, int track)
1307 {
1308         int error, errcnt;
1309
1310         drive&=3;
1311         if (unit[drive].track == track)
1312                 return 0;
1313         get_fdc(drive);
1314         if (!fd_motor_on(drive)) {
1315                 rel_fdc();
1316                 return -1;
1317         }
1318
1319         if (unit[drive].dirty == 1) {
1320                 del_timer (flush_track_timer + drive);
1321                 non_int_flush_track (drive);
1322         }
1323         errcnt = 0;
1324         while (errcnt < MAX_ERRORS) {
1325                 if (!fd_seek(drive, track))
1326                         return -1;
1327                 raw_read(drive);
1328                 error = (*unit[drive].dtype->read_fkt)(drive);
1329                 if (error == 0) {
1330                         rel_fdc();
1331                         return 0;
1332                 }
1333                 /* Read Error Handling: recalibrate and try again */
1334                 unit[drive].track = -1;
1335                 errcnt++;
1336         }
1337         rel_fdc();
1338         return -1;
1339 }
1340
1341 static void redo_fd_request(void)
1342 {
1343         unsigned int cnt, block, track, sector;
1344         int drive;
1345         struct amiga_floppy_struct *floppy;
1346         char *data;
1347         unsigned long flags;
1348
1349  repeat:
1350         if (!CURRENT) {
1351                 /* Nothing left to do */
1352                 return;
1353         }
1354
1355         floppy = CURRENT->rq_disk->private_data;
1356         drive = floppy - unit;
1357
1358         /* Here someone could investigate to be more efficient */
1359         for (cnt = 0; cnt < CURRENT->current_nr_sectors; cnt++) {
1360 #ifdef DEBUG
1361                 printk("fd: sector %ld + %d requested for %s\n",
1362                        CURRENT->sector,cnt,
1363                        (CURRENT->cmd==READ)?"read":"write");
1364 #endif
1365                 block = CURRENT->sector + cnt;
1366                 if ((int)block > floppy->blocks) {
1367                         end_request(CURRENT, 0);
1368                         goto repeat;
1369                 }
1370
1371                 track = block / (floppy->dtype->sects * floppy->type->sect_mult);
1372                 sector = block % (floppy->dtype->sects * floppy->type->sect_mult);
1373                 data = CURRENT->buffer + 512 * cnt;
1374 #ifdef DEBUG
1375                 printk("access to track %d, sector %d, with buffer at "
1376                        "0x%08lx\n", track, sector, data);
1377 #endif
1378
1379                 if ((rq_data_dir(CURRENT) != READ) && (rq_data_dir(CURRENT) != WRITE)) {
1380                         printk(KERN_WARNING "do_fd_request: unknown command\n");
1381                         end_request(CURRENT, 0);
1382                         goto repeat;
1383                 }
1384                 if (get_track(drive, track) == -1) {
1385                         end_request(CURRENT, 0);
1386                         goto repeat;
1387                 }
1388
1389                 switch (rq_data_dir(CURRENT)) {
1390                 case READ:
1391                         memcpy(data, floppy->trackbuf + sector * 512, 512);
1392                         break;
1393
1394                 case WRITE:
1395                         memcpy(floppy->trackbuf + sector * 512, data, 512);
1396
1397                         /* keep the drive spinning while writes are scheduled */
1398                         if (!fd_motor_on(drive)) {
1399                                 end_request(CURRENT, 0);
1400                                 goto repeat;
1401                         }
1402                         /*
1403                          * setup a callback to write the track buffer
1404                          * after a short (1 tick) delay.
1405                          */
1406                         local_irq_save(flags);
1407
1408                         floppy->dirty = 1;
1409                         /* reset the timer */
1410                         mod_timer (flush_track_timer + drive, jiffies + 1);
1411                         local_irq_restore(flags);
1412                         break;
1413                 }
1414         }
1415         CURRENT->nr_sectors -= CURRENT->current_nr_sectors;
1416         CURRENT->sector += CURRENT->current_nr_sectors;
1417
1418         end_request(CURRENT, 1);
1419         goto repeat;
1420 }
1421
1422 static void do_fd_request(request_queue_t * q)
1423 {
1424         redo_fd_request();
1425 }
1426
1427 static int fd_ioctl(struct inode *inode, struct file *filp,
1428                     unsigned int cmd, unsigned long param)
1429 {
1430         int drive = iminor(inode) & 3;
1431         static struct floppy_struct getprm;
1432
1433         switch(cmd){
1434         case HDIO_GETGEO:
1435         {
1436                 struct hd_geometry loc;
1437                 loc.heads = unit[drive].type->heads;
1438                 loc.sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;
1439                 loc.cylinders = unit[drive].type->tracks;
1440                 loc.start = 0;
1441                 if (copy_to_user((void *)param, (void *)&loc,
1442                                  sizeof(struct hd_geometry)))
1443                         return -EFAULT;
1444                 break;
1445         }
1446         case FDFMTBEG:
1447                 get_fdc(drive);
1448                 if (fd_ref[drive] > 1) {
1449                         rel_fdc();
1450                         return -EBUSY;
1451                 }
1452                 fsync_bdev(inode->i_bdev);
1453                 if (fd_motor_on(drive) == 0) {
1454                         rel_fdc();
1455                         return -ENODEV;
1456                 }
1457                 if (fd_calibrate(drive) == 0) {
1458                         rel_fdc();
1459                         return -ENXIO;
1460                 }
1461                 floppy_off(drive);
1462                 rel_fdc();
1463                 break;
1464         case FDFMTTRK:
1465                 if (param < unit[drive].type->tracks * unit[drive].type->heads)
1466                 {
1467                         get_fdc(drive);
1468                         if (fd_seek(drive,param) != 0){
1469                                 memset(unit[drive].trackbuf, FD_FILL_BYTE,
1470                                        unit[drive].dtype->sects * unit[drive].type->sect_mult * 512);
1471                                 non_int_flush_track(drive);
1472                         }
1473                         floppy_off(drive);
1474                         rel_fdc();
1475                 }
1476                 else
1477                         return -EINVAL;
1478                 break;
1479         case FDFMTEND:
1480                 floppy_off(drive);
1481                 invalidate_bdev(inode->i_bdev, 0);
1482                 break;
1483         case FDGETPRM:
1484                 memset((void *)&getprm, 0, sizeof (getprm));
1485                 getprm.track=unit[drive].type->tracks;
1486                 getprm.head=unit[drive].type->heads;
1487                 getprm.sect=unit[drive].dtype->sects * unit[drive].type->sect_mult;
1488                 getprm.size=unit[drive].blocks;
1489                 if (copy_to_user((void *)param,
1490                                  (void *)&getprm,
1491                                  sizeof(struct floppy_struct)))
1492                         return -EFAULT;
1493                 break;
1494         case FDSETPRM:
1495         case FDDEFPRM:
1496                 return -EINVAL;
1497         case FDFLUSH: /* unconditionally, even if not needed */
1498                 del_timer (flush_track_timer + drive);
1499                 non_int_flush_track(drive);
1500                 break;
1501 #ifdef RAW_IOCTL
1502         case IOCTL_RAW_TRACK:
1503                 if (copy_to_user((void *)param, raw_buf,
1504                                  unit[drive].type->read_size))
1505                         return -EFAULT;
1506                 else
1507                         return unit[drive].type->read_size;
1508 #endif
1509         default:
1510                 printk(KERN_DEBUG "fd_ioctl: unknown cmd %d for drive %d.",
1511                        cmd, drive);
1512                 return -ENOSYS;
1513         }
1514         return 0;
1515 }
1516
1517 static void fd_probe(int dev)
1518 {
1519         unsigned long code;
1520         int type;
1521         int drive;
1522
1523         drive = dev & 3;
1524         code = fd_get_drive_id(drive);
1525
1526         /* get drive type */
1527         for (type = 0; type < num_dr_types; type++)
1528                 if (drive_types[type].code == code)
1529                         break;
1530
1531         if (type >= num_dr_types) {
1532                 printk(KERN_WARNING "fd_probe: unsupported drive type "
1533                        "%08lx found\n", code);
1534                 unit[drive].type = &drive_types[num_dr_types-1]; /* FD_NODRIVE */
1535                 return;
1536         }
1537
1538         unit[drive].type = drive_types + type;
1539         unit[drive].track = -1;
1540
1541         unit[drive].disk = -1;
1542         unit[drive].motor = 0;
1543         unit[drive].busy = 0;
1544         unit[drive].status = -1;
1545 }
1546
1547 /*
1548  * floppy_open check for aliasing (/dev/fd0 can be the same as
1549  * /dev/PS0 etc), and disallows simultaneous access to the same
1550  * drive with different device numbers.
1551  */
1552 static int floppy_open(struct inode *inode, struct file *filp)
1553 {
1554         int drive = iminor(inode) & 3;
1555         int system =  (iminor(inode) & 4) >> 2;
1556         int old_dev;
1557         unsigned long flags;
1558
1559         old_dev = fd_device[drive];
1560
1561         if (fd_ref[drive] && old_dev != system)
1562                 return -EBUSY;
1563
1564         if (filp && filp->f_mode & 3) {
1565                 check_disk_change(inode->i_bdev);
1566                 if (filp->f_mode & 2 ) {
1567                         int wrprot;
1568
1569                         get_fdc(drive);
1570                         fd_select (drive);
1571                         wrprot = !(ciaa.pra & DSKPROT);
1572                         fd_deselect (drive);
1573                         rel_fdc();
1574
1575                         if (wrprot)
1576                                 return -EROFS;
1577                 }
1578         }
1579
1580         local_irq_save(flags);
1581         fd_ref[drive]++;
1582         fd_device[drive] = system;
1583         local_irq_restore(flags);
1584
1585         unit[drive].dtype=&data_types[system];
1586         unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
1587                 data_types[system].sects*unit[drive].type->sect_mult;
1588         set_capacity(unit[drive].gendisk, unit[drive].blocks);
1589
1590         printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
1591                unit[drive].type->name, data_types[system].name);
1592
1593         return 0;
1594 }
1595
1596 static int floppy_release(struct inode * inode, struct file * filp)
1597 {
1598         int drive = iminor(inode) & 3;
1599
1600         if (unit[drive].dirty == 1) {
1601                 del_timer (flush_track_timer + drive);
1602                 non_int_flush_track (drive);
1603         }
1604
1605         if (!fd_ref[drive]--) {
1606                 printk(KERN_CRIT "floppy_release with fd_ref == 0");
1607                 fd_ref[drive] = 0;
1608         }
1609 #ifdef MODULE
1610 /* the mod_use counter is handled this way */
1611         floppy_off (drive | 0x40000000);
1612 #endif
1613         return 0;
1614 }
1615
1616 /*
1617  * floppy-change is never called from an interrupt, so we can relax a bit
1618  * here, sleep etc. Note that floppy-on tries to set current_DOR to point
1619  * to the desired drive, but it will probably not survive the sleep if
1620  * several floppies are used at the same time: thus the loop.
1621  */
1622 static int amiga_floppy_change(struct gendisk *disk)
1623 {
1624         struct amiga_floppy_struct *p = disk->private_data;
1625         int drive = p - unit;
1626         int changed;
1627         static int first_time = 1;
1628
1629         if (first_time)
1630                 changed = first_time--;
1631         else {
1632                 get_fdc(drive);
1633                 fd_select (drive);
1634                 changed = !(ciaa.pra & DSKCHANGE);
1635                 fd_deselect (drive);
1636                 rel_fdc();
1637         }
1638
1639         if (changed) {
1640                 fd_probe(drive);
1641                 p->track = -1;
1642                 p->dirty = 0;
1643                 writepending = 0; /* if this was true before, too bad! */
1644                 writefromint = 0;
1645                 return 1;
1646         }
1647         return 0;
1648 }
1649
1650 static struct block_device_operations floppy_fops = {
1651         .owner          = THIS_MODULE,
1652         .open           = floppy_open,
1653         .release        = floppy_release,
1654         .ioctl          = fd_ioctl,
1655         .media_changed  = amiga_floppy_change,
1656 };
1657
1658 void __init amiga_floppy_setup (char *str, int *ints)
1659 {
1660         printk (KERN_INFO "amiflop: Setting default df0 to %x\n", ints[1]);
1661         fd_def_df0 = ints[1];
1662 }
1663
1664 static int __init fd_probe_drives(void)
1665 {
1666         int drive,drives,nomem;
1667
1668         printk(KERN_INFO "FD: probing units\n" KERN_INFO "found ");
1669         drives=0;
1670         nomem=0;
1671         for(drive=0;drive<FD_MAX_UNITS;drive++) {
1672                 struct gendisk *disk;
1673                 fd_probe(drive);
1674                 if (unit[drive].type->code == FD_NODRIVE)
1675                         continue;
1676                 disk = alloc_disk(1);
1677                 if (!disk) {
1678                         unit[drive].type->code = FD_NODRIVE;
1679                         continue;
1680                 }
1681                 unit[drive].gendisk = disk;
1682                 drives++;
1683                 if ((unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL)) == NULL) {
1684                         printk("no mem for ");
1685                         unit[drive].type = &drive_types[num_dr_types - 1]; /* FD_NODRIVE */
1686                         drives--;
1687                         nomem = 1;
1688                 }
1689                 printk("fd%d ",drive);
1690                 disk->major = FLOPPY_MAJOR;
1691                 disk->first_minor = drive;
1692                 disk->fops = &floppy_fops;
1693                 sprintf(disk->disk_name, "fd%d", drive);
1694                 disk->private_data = &unit[drive];
1695                 disk->queue = floppy_queue;
1696                 set_capacity(disk, 880*2);
1697                 add_disk(disk);
1698         }
1699         if ((drives > 0) || (nomem == 0)) {
1700                 if (drives == 0)
1701                         printk("no drives");
1702                 printk("\n");
1703                 return drives;
1704         }
1705         printk("\n");
1706         return -ENOMEM;
1707 }
1708
1709 static struct kobject *floppy_find(dev_t dev, int *part, void *data)
1710 {
1711         int drive = *part & 3;
1712         if (unit[drive].type->code == FD_NODRIVE)
1713                 return NULL;
1714         *part = 0;
1715         return get_disk(unit[drive].gendisk);
1716 }
1717
1718 int __init amiga_floppy_init(void)
1719 {
1720         int i, ret;
1721
1722         if (!AMIGAHW_PRESENT(AMI_FLOPPY))
1723                 return -ENXIO;
1724
1725         if (register_blkdev(FLOPPY_MAJOR,"fd"))
1726                 return -EBUSY;
1727
1728         /*
1729          *  We request DSKPTR, DSKLEN and DSKDATA only, because the other
1730          *  floppy registers are too spreaded over the custom register space
1731          */
1732         ret = -EBUSY;
1733         if (!request_mem_region(CUSTOM_PHYSADDR+0x20, 8, "amiflop [Paula]")) {
1734                 printk("fd: cannot get floppy registers\n");
1735                 goto out_blkdev;
1736         }
1737
1738         ret = -ENOMEM;
1739         if ((raw_buf = (char *)amiga_chip_alloc (RAW_BUF_SIZE, "Floppy")) ==
1740             NULL) {
1741                 printk("fd: cannot get chip mem buffer\n");
1742                 goto out_memregion;
1743         }
1744
1745         ret = -EBUSY;
1746         if (request_irq(IRQ_AMIGA_DSKBLK, fd_block_done, 0, "floppy_dma", NULL)) {
1747                 printk("fd: cannot get irq for dma\n");
1748                 goto out_irq;
1749         }
1750
1751         if (request_irq(IRQ_AMIGA_CIAA_TB, ms_isr, 0, "floppy_timer", NULL)) {
1752                 printk("fd: cannot get irq for timer\n");
1753                 goto out_irq2;
1754         }
1755
1756         ret = -ENOMEM;
1757         floppy_queue = blk_init_queue(do_fd_request, &amiflop_lock);
1758         if (!floppy_queue)
1759                 goto out_queue;
1760
1761         ret = -ENXIO;
1762         if (fd_probe_drives() < 1) /* No usable drives */
1763                 goto out_probe;
1764
1765         blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
1766                                 floppy_find, NULL, NULL);
1767
1768         /* initialize variables */
1769         init_timer(&motor_on_timer);
1770         motor_on_timer.expires = 0;
1771         motor_on_timer.data = 0;
1772         motor_on_timer.function = motor_on_callback;
1773         for (i = 0; i < FD_MAX_UNITS; i++) {
1774                 init_timer(&motor_off_timer[i]);
1775                 motor_off_timer[i].expires = 0;
1776                 motor_off_timer[i].data = i|0x80000000;
1777                 motor_off_timer[i].function = fd_motor_off;
1778                 init_timer(&flush_track_timer[i]);
1779                 flush_track_timer[i].expires = 0;
1780                 flush_track_timer[i].data = i;
1781                 flush_track_timer[i].function = flush_track_callback;
1782
1783                 unit[i].track = -1;
1784         }
1785
1786         init_timer(&post_write_timer);
1787         post_write_timer.expires = 0;
1788         post_write_timer.data = 0;
1789         post_write_timer.function = post_write;
1790
1791         for (i = 0; i < 128; i++)
1792                 mfmdecode[i]=255;
1793         for (i = 0; i < 16; i++)
1794                 mfmdecode[mfmencode[i]]=i;
1795
1796         /* make sure that disk DMA is enabled */
1797         custom.dmacon = DMAF_SETCLR | DMAF_DISK;
1798
1799         /* init ms timer */
1800         ciaa.crb = 8; /* one-shot, stop */
1801         return 0;
1802
1803 out_probe:
1804         blk_cleanup_queue(floppy_queue);
1805 out_queue:
1806         free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1807 out_irq2:
1808         free_irq(IRQ_AMIGA_DSKBLK, NULL);
1809 out_irq:
1810         amiga_chip_free(raw_buf);
1811 out_memregion:
1812         release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
1813 out_blkdev:
1814         unregister_blkdev(FLOPPY_MAJOR,"fd");
1815         return ret;
1816 }
1817
1818 #ifdef MODULE
1819
1820 int init_module(void)
1821 {
1822         if (!MACH_IS_AMIGA)
1823                 return -ENXIO;
1824         return amiga_floppy_init();
1825 }
1826
1827 #if 0 /* not safe to unload */
1828 void cleanup_module(void)
1829 {
1830         int i;
1831
1832         for( i = 0; i < FD_MAX_UNITS; i++) {
1833                 if (unit[i].type->code != FD_NODRIVE) {
1834                         del_gendisk(unit[i].gendisk);
1835                         put_disk(unit[i].gendisk);
1836                         kfree(unit[i].trackbuf);
1837                 }
1838         }
1839         blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
1840         free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1841         free_irq(IRQ_AMIGA_DSKBLK, NULL);
1842         custom.dmacon = DMAF_DISK; /* disable DMA */
1843         amiga_chip_free(raw_buf);
1844         blk_cleanup_queue(floppy_queue);
1845         release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
1846         unregister_blkdev(FLOPPY_MAJOR, "fd");
1847 }
1848 #endif
1849 #endif