drivers/block/amiflop.c

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This source file includes following definitions.
ms_isr
ms_delay
try_fdc
get_fdc
rel_fdc
fd_select
fd_deselect
motor_on_callback
fd_motor_on
fd_motor_off
floppy_off
fd_calibrate
fd_seek
fd_get_drive_id
fd_block_done
raw_read
raw_write
post_write
post_write_callback
scan_sync
checksum
decode
amiga_read
encode
encode_block
putsec
amiga_write
dos_crc
dos_hdr_crc
dos_data_crc
dos_decode_byte
dos_decode
dbg
dos_read
dos_encode_byte
dos_encode_block
ms_putsec
dos_write
flush_track_callback
non_int_flush_track
get_track
amiflop_rw_cur_segment
amiflop_queue_rq
fd_getgeo
fd_locked_ioctl
fd_ioctl
fd_probe
floppy_open
floppy_release
amiga_check_events
fd_alloc_disk
fd_probe_drives
floppy_find
amiga_floppy_probe
amiga_floppy_init
amiga_floppy_setup
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/amiga/amiflop.c
   4  *
   5  *  Copyright (C) 1993  Greg Harp
   6  *  Portions of this driver are based on code contributed by Brad Pepers
   7  *  
   8  *  revised 28.5.95 by Joerg Dorchain
   9  *  - now no bugs(?) any more for both HD & DD
  10  *  - added support for 40 Track 5.25" drives, 80-track hopefully behaves
  11  *    like 3.5" dd (no way to test - are there any 5.25" drives out there
  12  *    that work on an A4000?)
  13  *  - wrote formatting routine (maybe dirty, but works)
  14  *
  15  *  june/july 1995 added ms-dos support by Joerg Dorchain
  16  *  (portions based on messydos.device and various contributors)
  17  *  - currently only 9 and 18 sector disks
  18  *
  19  *  - fixed a bug with the internal trackbuffer when using multiple 
  20  *    disks the same time
  21  *  - made formatting a bit safer
  22  *  - added command line and machine based default for "silent" df0
  23  *
  24  *  december 1995 adapted for 1.2.13pl4 by Joerg Dorchain
  25  *  - works but I think it's inefficient. (look in redo_fd_request)
  26  *    But the changes were very efficient. (only three and a half lines)
  27  *
  28  *  january 1996 added special ioctl for tracking down read/write problems
  29  *  - usage ioctl(d, RAW_TRACK, ptr); the raw track buffer (MFM-encoded data
  30  *    is copied to area. (area should be large enough since no checking is
  31  *    done - 30K is currently sufficient). return the actual size of the
  32  *    trackbuffer
  33  *  - replaced udelays() by a timer (CIAA timer B) for the waits 
  34  *    needed for the disk mechanic.
  35  *
  36  *  february 1996 fixed error recovery and multiple disk access
  37  *  - both got broken the first time I tampered with the driver :-(
  38  *  - still not safe, but better than before
  39  *
  40  *  revised Marts 3rd, 1996 by Jes Sorensen for use in the 1.3.28 kernel.
  41  *  - Minor changes to accept the kdev_t.
  42  *  - Replaced some more udelays with ms_delays. Udelay is just a loop,
  43  *    and so the delay will be different depending on the given
  44  *    processor :-(
  45  *  - The driver could use a major cleanup because of the new
  46  *    major/minor handling that came with kdev_t. It seems to work for
  47  *    the time being, but I can't guarantee that it will stay like
  48  *    that when we start using 16 (24?) bit minors.
  49  *
  50  * restructured jan 1997 by Joerg Dorchain
  51  * - Fixed Bug accessing multiple disks
  52  * - some code cleanup
  53  * - added trackbuffer for each drive to speed things up
  54  * - fixed some race conditions (who finds the next may send it to me ;-)
  55  */
  56 
  57 #include <linux/module.h>
  58 #include <linux/slab.h>
  59 
  60 #include <linux/fd.h>
  61 #include <linux/hdreg.h>
  62 #include <linux/delay.h>
  63 #include <linux/init.h>
  64 #include <linux/mutex.h>
  65 #include <linux/fs.h>
  66 #include <linux/blk-mq.h>
  67 #include <linux/elevator.h>
  68 #include <linux/interrupt.h>
  69 #include <linux/platform_device.h>
  70 
  71 #include <asm/setup.h>
  72 #include <linux/uaccess.h>
  73 #include <asm/amigahw.h>
  74 #include <asm/amigaints.h>
  75 #include <asm/irq.h>
  76 
  77 #undef DEBUG /* print _LOTS_ of infos */
  78 
  79 #define RAW_IOCTL
  80 #ifdef RAW_IOCTL
  81 #define IOCTL_RAW_TRACK 0x5254524B  /* 'RTRK' */
  82 #endif
  83 
  84 /*
  85  *  Defines
  86  */
  87 
  88 /*
  89  * CIAAPRA bits (read only)
  90  */
  91 
  92 #define DSKRDY      (0x1<<5)        /* disk ready when low */
  93 #define DSKTRACK0   (0x1<<4)        /* head at track zero when low */
  94 #define DSKPROT     (0x1<<3)        /* disk protected when low */
  95 #define DSKCHANGE   (0x1<<2)        /* low when disk removed */
  96 
  97 /*
  98  * CIAAPRB bits (read/write)
  99  */
 100 
 101 #define DSKMOTOR    (0x1<<7)        /* motor on when low */
 102 #define DSKSEL3     (0x1<<6)        /* select drive 3 when low */
 103 #define DSKSEL2     (0x1<<5)        /* select drive 2 when low */
 104 #define DSKSEL1     (0x1<<4)        /* select drive 1 when low */
 105 #define DSKSEL0     (0x1<<3)        /* select drive 0 when low */
 106 #define DSKSIDE     (0x1<<2)        /* side selection: 0 = upper, 1 = lower */
 107 #define DSKDIREC    (0x1<<1)        /* step direction: 0=in, 1=out (to trk 0) */
 108 #define DSKSTEP     (0x1)           /* pulse low to step head 1 track */
 109 
 110 /*
 111  * DSKBYTR bits (read only)
 112  */
 113 
 114 #define DSKBYT      (1<<15)         /* register contains valid byte when set */
 115 #define DMAON       (1<<14)         /* disk DMA enabled */
 116 #define DISKWRITE   (1<<13)         /* disk write bit in DSKLEN enabled */
 117 #define WORDEQUAL   (1<<12)         /* DSKSYNC register match when true */
 118 /* bits 7-0 are data */
 119 
 120 /*
 121  * ADKCON/ADKCONR bits
 122  */
 123 
 124 #ifndef SETCLR
 125 #define ADK_SETCLR      (1<<15)     /* control bit */
 126 #endif
 127 #define ADK_PRECOMP1    (1<<14)     /* precompensation selection */
 128 #define ADK_PRECOMP0    (1<<13)     /* 00=none, 01=140ns, 10=280ns, 11=500ns */
 129 #define ADK_MFMPREC     (1<<12)     /* 0=GCR precomp., 1=MFM precomp. */
 130 #define ADK_WORDSYNC    (1<<10)     /* enable DSKSYNC auto DMA */
 131 #define ADK_MSBSYNC     (1<<9)      /* when 1, enable sync on MSbit (for GCR) */
 132 #define ADK_FAST        (1<<8)      /* bit cell: 0=2us (GCR), 1=1us (MFM) */
 133 
 134 /*
 135  * DSKLEN bits
 136  */
 137 
 138 #define DSKLEN_DMAEN    (1<<15)
 139 #define DSKLEN_WRITE    (1<<14)
 140 
 141 /*
 142  * INTENA/INTREQ bits
 143  */
 144 
 145 #define DSKINDEX    (0x1<<4)        /* DSKINDEX bit */
 146 
 147 /*
 148  * Misc
 149  */
 150 
 151 #define MFM_SYNC    0x4489          /* standard MFM sync value */
 152 
 153 /* Values for FD_COMMAND */
 154 #define FD_RECALIBRATE          0x07    /* move to track 0 */
 155 #define FD_SEEK                 0x0F    /* seek track */
 156 #define FD_READ                 0xE6    /* read with MT, MFM, SKip deleted */
 157 #define FD_WRITE                0xC5    /* write with MT, MFM */
 158 #define FD_SENSEI               0x08    /* Sense Interrupt Status */
 159 #define FD_SPECIFY              0x03    /* specify HUT etc */
 160 #define FD_FORMAT               0x4D    /* format one track */
 161 #define FD_VERSION              0x10    /* get version code */
 162 #define FD_CONFIGURE            0x13    /* configure FIFO operation */
 163 #define FD_PERPENDICULAR        0x12    /* perpendicular r/w mode */
 164 
 165 #define FD_MAX_UNITS    4       /* Max. Number of drives */
 166 #define FLOPPY_MAX_SECTORS      22      /* Max. Number of sectors per track */
 167 
 168 struct fd_data_type {
 169         char *name;             /* description of data type */
 170         int sects;              /* sectors per track */
 171         int (*read_fkt)(int);   /* read whole track */
 172         void (*write_fkt)(int); /* write whole track */
 173 };
 174 
 175 struct fd_drive_type {
 176         unsigned long code;             /* code returned from drive */
 177         char *name;                     /* description of drive */
 178         unsigned int tracks;    /* number of tracks */
 179         unsigned int heads;             /* number of heads */
 180         unsigned int read_size; /* raw read size for one track */
 181         unsigned int write_size;        /* raw write size for one track */
 182         unsigned int sect_mult; /* sectors and gap multiplier (HD = 2) */
 183         unsigned int precomp1;  /* start track for precomp 1 */
 184         unsigned int precomp2;  /* start track for precomp 2 */
 185         unsigned int step_delay;        /* time (in ms) for delay after step */
 186         unsigned int settle_time;       /* time to settle after dir change */
 187         unsigned int side_time; /* time needed to change sides */
 188 };
 189 
 190 struct amiga_floppy_struct {
 191         struct fd_drive_type *type;     /* type of floppy for this unit */
 192         struct fd_data_type *dtype;     /* type of floppy for this unit */
 193         int track;                      /* current track (-1 == unknown) */
 194         unsigned char *trackbuf;        /* current track (kmaloc()'d */
 195 
 196         int blocks;                     /* total # blocks on disk */
 197 
 198         int changed;                    /* true when not known */
 199         int disk;                       /* disk in drive (-1 == unknown) */
 200         int motor;                      /* true when motor is at speed */
 201         int busy;                       /* true when drive is active */
 202         int dirty;                      /* true when trackbuf is not on disk */
 203         int status;                     /* current error code for unit */
 204         struct gendisk *gendisk;
 205         struct blk_mq_tag_set tag_set;
 206 };
 207 
 208 /*
 209  *  Error codes
 210  */
 211 #define FD_OK           0       /* operation succeeded */
 212 #define FD_ERROR        -1      /* general error (seek, read, write, etc) */
 213 #define FD_NOUNIT       1       /* unit does not exist */
 214 #define FD_UNITBUSY     2       /* unit already active */
 215 #define FD_NOTACTIVE    3       /* unit is not active */
 216 #define FD_NOTREADY     4       /* unit is not ready (motor not on/no disk) */
 217 
 218 #define MFM_NOSYNC      1
 219 #define MFM_HEADER      2
 220 #define MFM_DATA        3
 221 #define MFM_TRACK       4
 222 
 223 /*
 224  *  Floppy ID values
 225  */
 226 #define FD_NODRIVE      0x00000000  /* response when no unit is present */
 227 #define FD_DD_3         0xffffffff  /* double-density 3.5" (880K) drive */
 228 #define FD_HD_3         0x55555555  /* high-density 3.5" (1760K) drive */
 229 #define FD_DD_5         0xaaaaaaaa  /* double-density 5.25" (440K) drive */
 230 
 231 static DEFINE_MUTEX(amiflop_mutex);
 232 static unsigned long int fd_def_df0 = FD_DD_3;     /* default for df0 if it doesn't identify */
 233 
 234 module_param(fd_def_df0, ulong, 0);
 235 MODULE_LICENSE("GPL");
 236 
 237 /*
 238  *  Macros
 239  */
 240 #define MOTOR_ON        (ciab.prb &= ~DSKMOTOR)
 241 #define MOTOR_OFF       (ciab.prb |= DSKMOTOR)
 242 #define SELECT(mask)    (ciab.prb &= ~mask)
 243 #define DESELECT(mask)  (ciab.prb |= mask)
 244 #define SELMASK(drive)  (1 << (3 + (drive & 3)))
 245 
 246 static struct fd_drive_type drive_types[] = {
 247 /*  code        name       tr he   rdsz   wrsz sm pc1 pc2 sd  st st*/
 248 /*  warning: times are now in milliseconds (ms)                    */
 249 { FD_DD_3,      "DD 3.5",  80, 2, 14716, 13630, 1, 80,161, 3, 18, 1},
 250 { FD_HD_3,      "HD 3.5",  80, 2, 28344, 27258, 2, 80,161, 3, 18, 1},
 251 { FD_DD_5,      "DD 5.25", 40, 2, 14716, 13630, 1, 40, 81, 6, 30, 2},
 252 { FD_NODRIVE, "No Drive", 0, 0,     0,     0, 0,  0,  0,  0,  0, 0}
 253 };
 254 static int num_dr_types = ARRAY_SIZE(drive_types);
 255 
 256 static int amiga_read(int), dos_read(int);
 257 static void amiga_write(int), dos_write(int);
 258 static struct fd_data_type data_types[] = {
 259         { "Amiga", 11 , amiga_read, amiga_write},
 260         { "MS-Dos", 9, dos_read, dos_write}
 261 };
 262 
 263 /* current info on each unit */
 264 static struct amiga_floppy_struct unit[FD_MAX_UNITS];
 265 
 266 static struct timer_list flush_track_timer[FD_MAX_UNITS];
 267 static struct timer_list post_write_timer;
 268 static unsigned long post_write_timer_drive;
 269 static struct timer_list motor_on_timer;
 270 static struct timer_list motor_off_timer[FD_MAX_UNITS];
 271 static int on_attempts;
 272 
 273 /* Synchronization of FDC access */
 274 /* request loop (trackbuffer) */
 275 static volatile int fdc_busy = -1;
 276 static volatile int fdc_nested;
 277 static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
 278  
 279 static DECLARE_COMPLETION(motor_on_completion);
 280 
 281 static volatile int selected = -1;      /* currently selected drive */
 282 
 283 static int writepending;
 284 static int writefromint;
 285 static char *raw_buf;
 286 
 287 static DEFINE_SPINLOCK(amiflop_lock);
 288 
 289 #define RAW_BUF_SIZE 30000  /* size of raw disk data */
 290 
 291 /*
 292  * These are global variables, as that's the easiest way to give
 293  * information to interrupts. They are the data used for the current
 294  * request.
 295  */
 296 static volatile char block_flag;
 297 static DECLARE_WAIT_QUEUE_HEAD(wait_fd_block);
 298 
 299 /* MS-Dos MFM Coding tables (should go quick and easy) */
 300 static unsigned char mfmencode[16]={
 301         0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15,
 302         0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55
 303 };
 304 static unsigned char mfmdecode[128];
 305 
 306 /* floppy internal millisecond timer stuff */
 307 static DECLARE_COMPLETION(ms_wait_completion);
 308 #define MS_TICKS ((amiga_eclock+50)/1000)
 309 
 310 /*
 311  * Note that MAX_ERRORS=X doesn't imply that we retry every bad read
 312  * max X times - some types of errors increase the errorcount by 2 or
 313  * even 3, so we might actually retry only X/2 times before giving up.
 314  */
 315 #define MAX_ERRORS 12
 316 
 317 #define custom amiga_custom
 318 
 319 /* Prevent "aliased" accesses. */
 320 static int fd_ref[4] = { 0,0,0,0 };
 321 static int fd_device[4] = { 0, 0, 0, 0 };
 322 
 323 /*
 324  * Here come the actual hardware access and helper functions.
 325  * They are not reentrant and single threaded because all drives
 326  * share the same hardware and the same trackbuffer.
 327  */
 328 
 329 /* Milliseconds timer */
 330 
 331 static irqreturn_t ms_isr(int irq, void *dummy)
 332 {
 333         complete(&ms_wait_completion);
 334         return IRQ_HANDLED;
 335 }
 336 
 337 /* all waits are queued up 
 338    A more generic routine would do a schedule a la timer.device */
 339 static void ms_delay(int ms)
 340 {
 341         int ticks;
 342         static DEFINE_MUTEX(mutex);
 343 
 344         if (ms > 0) {
 345                 mutex_lock(&mutex);
 346                 ticks = MS_TICKS*ms-1;
 347                 ciaa.tblo=ticks%256;
 348                 ciaa.tbhi=ticks/256;
 349                 ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */
 350                 wait_for_completion(&ms_wait_completion);
 351                 mutex_unlock(&mutex);
 352         }
 353 }
 354 
 355 /* Hardware semaphore */
 356 
 357 /* returns true when we would get the semaphore */
 358 static inline int try_fdc(int drive)
 359 {
 360         drive &= 3;
 361         return ((fdc_busy < 0) || (fdc_busy == drive));
 362 }
 363 
 364 static void get_fdc(int drive)
 365 {
 366         unsigned long flags;
 367 
 368         drive &= 3;
 369 #ifdef DEBUG
 370         printk("get_fdc: drive %d  fdc_busy %d  fdc_nested %d\n",drive,fdc_busy,fdc_nested);
 371 #endif
 372         local_irq_save(flags);
 373         wait_event(fdc_wait, try_fdc(drive));
 374         fdc_busy = drive;
 375         fdc_nested++;
 376         local_irq_restore(flags);
 377 }
 378 
 379 static inline void rel_fdc(void)
 380 {
 381 #ifdef DEBUG
 382         if (fdc_nested == 0)
 383                 printk("fd: unmatched rel_fdc\n");
 384         printk("rel_fdc: fdc_busy %d fdc_nested %d\n",fdc_busy,fdc_nested);
 385 #endif
 386         fdc_nested--;
 387         if (fdc_nested == 0) {
 388                 fdc_busy = -1;
 389                 wake_up(&fdc_wait);
 390         }
 391 }
 392 
 393 static void fd_select (int drive)
 394 {
 395         unsigned char prb = ~0;
 396 
 397         drive&=3;
 398 #ifdef DEBUG
 399         printk("selecting %d\n",drive);
 400 #endif
 401         if (drive == selected)
 402                 return;
 403         get_fdc(drive);
 404         selected = drive;
 405 
 406         if (unit[drive].track % 2 != 0)
 407                 prb &= ~DSKSIDE;
 408         if (unit[drive].motor == 1)
 409                 prb &= ~DSKMOTOR;
 410         ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
 411         ciab.prb = prb;
 412         prb &= ~SELMASK(drive);
 413         ciab.prb = prb;
 414         rel_fdc();
 415 }
 416 
 417 static void fd_deselect (int drive)
 418 {
 419         unsigned char prb;
 420         unsigned long flags;
 421 
 422         drive&=3;
 423 #ifdef DEBUG
 424         printk("deselecting %d\n",drive);
 425 #endif
 426         if (drive != selected) {
 427                 printk(KERN_WARNING "Deselecting drive %d while %d was selected!\n",drive,selected);
 428                 return;
 429         }
 430 
 431         get_fdc(drive);
 432         local_irq_save(flags);
 433 
 434         selected = -1;
 435 
 436         prb = ciab.prb;
 437         prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
 438         ciab.prb = prb;
 439 
 440         local_irq_restore (flags);
 441         rel_fdc();
 442 
 443 }
 444 
 445 static void motor_on_callback(struct timer_list *unused)
 446 {
 447         if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {
 448                 complete_all(&motor_on_completion);
 449         } else {
 450                 motor_on_timer.expires = jiffies + HZ/10;
 451                 add_timer(&motor_on_timer);
 452         }
 453 }
 454 
 455 static int fd_motor_on(int nr)
 456 {
 457         nr &= 3;
 458 
 459         del_timer(motor_off_timer + nr);
 460 
 461         if (!unit[nr].motor) {
 462                 unit[nr].motor = 1;
 463                 fd_select(nr);
 464 
 465                 reinit_completion(&motor_on_completion);
 466                 mod_timer(&motor_on_timer, jiffies + HZ/2);
 467 
 468                 on_attempts = 10;
 469                 wait_for_completion(&motor_on_completion);
 470                 fd_deselect(nr);
 471         }
 472 
 473         if (on_attempts == 0) {
 474                 on_attempts = -1;
 475 #if 0
 476                 printk (KERN_ERR "motor_on failed, turning motor off\n");
 477                 fd_motor_off (motor_off_timer + nr);
 478                 return 0;
 479 #else
 480                 printk (KERN_WARNING "DSKRDY not set after 1.5 seconds - assuming drive is spinning notwithstanding\n");
 481 #endif
 482         }
 483 
 484         return 1;
 485 }
 486 
 487 static void fd_motor_off(struct timer_list *timer)
 488 {
 489         unsigned long drive = ((unsigned long)timer -
 490                                (unsigned long)&motor_off_timer[0]) /
 491                                         sizeof(motor_off_timer[0]);
 492 
 493         drive&=3;
 494         if (!try_fdc(drive)) {
 495                 /* We would be blocked in an interrupt, so try again later */
 496                 timer->expires = jiffies + 1;
 497                 add_timer(timer);
 498                 return;
 499         }
 500         unit[drive].motor = 0;
 501         fd_select(drive);
 502         udelay (1);
 503         fd_deselect(drive);
 504 }
 505 
 506 static void floppy_off (unsigned int nr)
 507 {
 508         int drive;
 509 
 510         drive = nr & 3;
 511         mod_timer(motor_off_timer + drive, jiffies + 3*HZ);
 512 }
 513 
 514 static int fd_calibrate(int drive)
 515 {
 516         unsigned char prb;
 517         int n;
 518 
 519         drive &= 3;
 520         get_fdc(drive);
 521         if (!fd_motor_on (drive))
 522                 return 0;
 523         fd_select (drive);
 524         prb = ciab.prb;
 525         prb |= DSKSIDE;
 526         prb &= ~DSKDIREC;
 527         ciab.prb = prb;
 528         for (n = unit[drive].type->tracks/2; n != 0; --n) {
 529                 if (ciaa.pra & DSKTRACK0)
 530                         break;
 531                 prb &= ~DSKSTEP;
 532                 ciab.prb = prb;
 533                 prb |= DSKSTEP;
 534                 udelay (2);
 535                 ciab.prb = prb;
 536                 ms_delay(unit[drive].type->step_delay);
 537         }
 538         ms_delay (unit[drive].type->settle_time);
 539         prb |= DSKDIREC;
 540         n = unit[drive].type->tracks + 20;
 541         for (;;) {
 542                 prb &= ~DSKSTEP;
 543                 ciab.prb = prb;
 544                 prb |= DSKSTEP;
 545                 udelay (2);
 546                 ciab.prb = prb;
 547                 ms_delay(unit[drive].type->step_delay + 1);
 548                 if ((ciaa.pra & DSKTRACK0) == 0)
 549                         break;
 550                 if (--n == 0) {
 551                         printk (KERN_ERR "fd%d: calibrate failed, turning motor off\n", drive);
 552                         fd_motor_off (motor_off_timer + drive);
 553                         unit[drive].track = -1;
 554                         rel_fdc();
 555                         return 0;
 556                 }
 557         }
 558         unit[drive].track = 0;
 559         ms_delay(unit[drive].type->settle_time);
 560 
 561         rel_fdc();
 562         fd_deselect(drive);
 563         return 1;
 564 }
 565 
 566 static int fd_seek(int drive, int track)
 567 {
 568         unsigned char prb;
 569         int cnt;
 570 
 571 #ifdef DEBUG
 572         printk("seeking drive %d to track %d\n",drive,track);
 573 #endif
 574         drive &= 3;
 575         get_fdc(drive);
 576         if (unit[drive].track == track) {
 577                 rel_fdc();
 578                 return 1;
 579         }
 580         if (!fd_motor_on(drive)) {
 581                 rel_fdc();
 582                 return 0;
 583         }
 584         if (unit[drive].track < 0 && !fd_calibrate(drive)) {
 585                 rel_fdc();
 586                 return 0;
 587         }
 588 
 589         fd_select (drive);
 590         cnt = unit[drive].track/2 - track/2;
 591         prb = ciab.prb;
 592         prb |= DSKSIDE | DSKDIREC;
 593         if (track % 2 != 0)
 594                 prb &= ~DSKSIDE;
 595         if (cnt < 0) {
 596                 cnt = - cnt;
 597                 prb &= ~DSKDIREC;
 598         }
 599         ciab.prb = prb;
 600         if (track % 2 != unit[drive].track % 2)
 601                 ms_delay (unit[drive].type->side_time);
 602         unit[drive].track = track;
 603         if (cnt == 0) {
 604                 rel_fdc();
 605                 fd_deselect(drive);
 606                 return 1;
 607         }
 608         do {
 609                 prb &= ~DSKSTEP;
 610                 ciab.prb = prb;
 611                 prb |= DSKSTEP;
 612                 udelay (1);
 613                 ciab.prb = prb;
 614                 ms_delay (unit[drive].type->step_delay);
 615         } while (--cnt != 0);
 616         ms_delay (unit[drive].type->settle_time);
 617 
 618         rel_fdc();
 619         fd_deselect(drive);
 620         return 1;
 621 }
 622 
 623 static unsigned long fd_get_drive_id(int drive)
 624 {
 625         int i;
 626         ulong id = 0;
 627 
 628         drive&=3;
 629         get_fdc(drive);
 630         /* set up for ID */
 631         MOTOR_ON;
 632         udelay(2);
 633         SELECT(SELMASK(drive));
 634         udelay(2);
 635         DESELECT(SELMASK(drive));
 636         udelay(2);
 637         MOTOR_OFF;
 638         udelay(2);
 639         SELECT(SELMASK(drive));
 640         udelay(2);
 641         DESELECT(SELMASK(drive));
 642         udelay(2);
 643 
 644         /* loop and read disk ID */
 645         for (i=0; i<32; i++) {
 646                 SELECT(SELMASK(drive));
 647                 udelay(2);
 648 
 649                 /* read and store value of DSKRDY */
 650                 id <<= 1;
 651                 id |= (ciaa.pra & DSKRDY) ? 0 : 1;      /* cia regs are low-active! */
 652 
 653                 DESELECT(SELMASK(drive));
 654         }
 655 
 656         rel_fdc();
 657 
 658         /*
 659          * RB: At least A500/A2000's df0: don't identify themselves.
 660          * As every (real) Amiga has at least a 3.5" DD drive as df0:
 661          * we default to that if df0: doesn't identify as a certain
 662          * type.
 663          */
 664         if(drive == 0 && id == FD_NODRIVE)
 665         {
 666                 id = fd_def_df0;
 667                 printk(KERN_NOTICE "fd: drive 0 didn't identify, setting default %08lx\n", (ulong)fd_def_df0);
 668         }
 669         /* return the ID value */
 670         return (id);
 671 }
 672 
 673 static irqreturn_t fd_block_done(int irq, void *dummy)
 674 {
 675         if (block_flag)
 676                 custom.dsklen = 0x4000;
 677 
 678         if (block_flag == 2) { /* writing */
 679                 writepending = 2;
 680                 post_write_timer.expires = jiffies + 1; /* at least 2 ms */
 681                 post_write_timer_drive = selected;
 682                 add_timer(&post_write_timer);
 683         }
 684         else {                /* reading */
 685                 block_flag = 0;
 686                 wake_up (&wait_fd_block);
 687         }
 688         return IRQ_HANDLED;
 689 }
 690 
 691 static void raw_read(int drive)
 692 {
 693         drive&=3;
 694         get_fdc(drive);
 695         wait_event(wait_fd_block, !block_flag);
 696         fd_select(drive);
 697         /* setup adkcon bits correctly */
 698         custom.adkcon = ADK_MSBSYNC;
 699         custom.adkcon = ADK_SETCLR|ADK_WORDSYNC|ADK_FAST;
 700 
 701         custom.dsksync = MFM_SYNC;
 702 
 703         custom.dsklen = 0;
 704         custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
 705         custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
 706         custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
 707 
 708         block_flag = 1;
 709 
 710         wait_event(wait_fd_block, !block_flag);
 711 
 712         custom.dsklen = 0;
 713         fd_deselect(drive);
 714         rel_fdc();
 715 }
 716 
 717 static int raw_write(int drive)
 718 {
 719         ushort adk;
 720 
 721         drive&=3;
 722         get_fdc(drive); /* corresponds to rel_fdc() in post_write() */
 723         if ((ciaa.pra & DSKPROT) == 0) {
 724                 rel_fdc();
 725                 return 0;
 726         }
 727         wait_event(wait_fd_block, !block_flag);
 728         fd_select(drive);
 729         /* clear adkcon bits */
 730         custom.adkcon = ADK_PRECOMP1|ADK_PRECOMP0|ADK_WORDSYNC|ADK_MSBSYNC;
 731         /* set appropriate adkcon bits */
 732         adk = ADK_SETCLR|ADK_FAST;
 733         if ((ulong)unit[drive].track >= unit[drive].type->precomp2)
 734                 adk |= ADK_PRECOMP1;
 735         else if ((ulong)unit[drive].track >= unit[drive].type->precomp1)
 736                 adk |= ADK_PRECOMP0;
 737         custom.adkcon = adk;
 738 
 739         custom.dsklen = DSKLEN_WRITE;
 740         custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
 741         custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
 742         custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
 743 
 744         block_flag = 2;
 745         return 1;
 746 }
 747 
 748 /*
 749  * to be called at least 2ms after the write has finished but before any
 750  * other access to the hardware.
 751  */
 752 static void post_write (unsigned long drive)
 753 {
 754 #ifdef DEBUG
 755         printk("post_write for drive %ld\n",drive);
 756 #endif
 757         drive &= 3;
 758         custom.dsklen = 0;
 759         block_flag = 0;
 760         writepending = 0;
 761         writefromint = 0;
 762         unit[drive].dirty = 0;
 763         wake_up(&wait_fd_block);
 764         fd_deselect(drive);
 765         rel_fdc(); /* corresponds to get_fdc() in raw_write */
 766 }
 767 
 768 static void post_write_callback(struct timer_list *timer)
 769 {
 770         post_write(post_write_timer_drive);
 771 }
 772 
 773 /*
 774  * The following functions are to convert the block contents into raw data
 775  * written to disk and vice versa.
 776  * (Add other formats here ;-))
 777  */
 778 
 779 static unsigned long scan_sync(unsigned long raw, unsigned long end)
 780 {
 781         ushort *ptr = (ushort *)raw, *endp = (ushort *)end;
 782 
 783         while (ptr < endp && *ptr++ != 0x4489)
 784                 ;
 785         if (ptr < endp) {
 786                 while (*ptr == 0x4489 && ptr < endp)
 787                         ptr++;
 788                 return (ulong)ptr;
 789         }
 790         return 0;
 791 }
 792 
 793 static inline unsigned long checksum(unsigned long *addr, int len)
 794 {
 795         unsigned long csum = 0;
 796 
 797         len /= sizeof(*addr);
 798         while (len-- > 0)
 799                 csum ^= *addr++;
 800         csum = ((csum>>1) & 0x55555555)  ^  (csum & 0x55555555);
 801 
 802         return csum;
 803 }
 804 
 805 static unsigned long decode (unsigned long *data, unsigned long *raw,
 806                              int len)
 807 {
 808         ulong *odd, *even;
 809 
 810         /* convert length from bytes to longwords */
 811         len >>= 2;
 812         odd = raw;
 813         even = odd + len;
 814 
 815         /* prepare return pointer */
 816         raw += len * 2;
 817 
 818         do {
 819                 *data++ = ((*odd++ & 0x55555555) << 1) | (*even++ & 0x55555555);
 820         } while (--len != 0);
 821 
 822         return (ulong)raw;
 823 }
 824 
 825 struct header {
 826         unsigned char magic;
 827         unsigned char track;
 828         unsigned char sect;
 829         unsigned char ord;
 830         unsigned char labels[16];
 831         unsigned long hdrchk;
 832         unsigned long datachk;
 833 };
 834 
 835 static int amiga_read(int drive)
 836 {
 837         unsigned long raw;
 838         unsigned long end;
 839         int scnt;
 840         unsigned long csum;
 841         struct header hdr;
 842 
 843         drive&=3;
 844         raw = (long) raw_buf;
 845         end = raw + unit[drive].type->read_size;
 846 
 847         for (scnt = 0;scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
 848                 if (!(raw = scan_sync(raw, end))) {
 849                         printk (KERN_INFO "can't find sync for sector %d\n", scnt);
 850                         return MFM_NOSYNC;
 851                 }
 852 
 853                 raw = decode ((ulong *)&hdr.magic, (ulong *)raw, 4);
 854                 raw = decode ((ulong *)&hdr.labels, (ulong *)raw, 16);
 855                 raw = decode ((ulong *)&hdr.hdrchk, (ulong *)raw, 4);
 856                 raw = decode ((ulong *)&hdr.datachk, (ulong *)raw, 4);
 857                 csum = checksum((ulong *)&hdr,
 858                                 (char *)&hdr.hdrchk-(char *)&hdr);
 859 
 860 #ifdef DEBUG
 861                 printk ("(%x,%d,%d,%d) (%lx,%lx,%lx,%lx) %lx %lx\n",
 862                         hdr.magic, hdr.track, hdr.sect, hdr.ord,
 863                         *(ulong *)&hdr.labels[0], *(ulong *)&hdr.labels[4],
 864                         *(ulong *)&hdr.labels[8], *(ulong *)&hdr.labels[12],
 865                         hdr.hdrchk, hdr.datachk);
 866 #endif
 867 
 868                 if (hdr.hdrchk != csum) {
 869                         printk(KERN_INFO "MFM_HEADER: %08lx,%08lx\n", hdr.hdrchk, csum);
 870                         return MFM_HEADER;
 871                 }
 872 
 873                 /* verify track */
 874                 if (hdr.track != unit[drive].track) {
 875                         printk(KERN_INFO "MFM_TRACK: %d, %d\n", hdr.track, unit[drive].track);
 876                         return MFM_TRACK;
 877                 }
 878 
 879                 raw = decode ((ulong *)(unit[drive].trackbuf + hdr.sect*512),
 880                               (ulong *)raw, 512);
 881                 csum = checksum((ulong *)(unit[drive].trackbuf + hdr.sect*512), 512);
 882 
 883                 if (hdr.datachk != csum) {
 884                         printk(KERN_INFO "MFM_DATA: (%x:%d:%d:%d) sc=%d %lx, %lx\n",
 885                                hdr.magic, hdr.track, hdr.sect, hdr.ord, scnt,
 886                                hdr.datachk, csum);
 887                         printk (KERN_INFO "data=(%lx,%lx,%lx,%lx)\n",
 888                                 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[0],
 889                                 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[1],
 890                                 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[2],
 891                                 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[3]);
 892                         return MFM_DATA;
 893                 }
 894         }
 895 
 896         return 0;
 897 }
 898 
 899 static void encode(unsigned long data, unsigned long *dest)
 900 {
 901         unsigned long data2;
 902 
 903         data &= 0x55555555;
 904         data2 = data ^ 0x55555555;
 905         data |= ((data2 >> 1) | 0x80000000) & (data2 << 1);
 906 
 907         if (*(dest - 1) & 0x00000001)
 908                 data &= 0x7FFFFFFF;
 909 
 910         *dest = data;
 911 }
 912 
 913 static void encode_block(unsigned long *dest, unsigned long *src, int len)
 914 {
 915         int cnt, to_cnt = 0;
 916         unsigned long data;
 917 
 918         /* odd bits */
 919         for (cnt = 0; cnt < len / 4; cnt++) {
 920                 data = src[cnt] >> 1;
 921                 encode(data, dest + to_cnt++);
 922         }
 923 
 924         /* even bits */
 925         for (cnt = 0; cnt < len / 4; cnt++) {
 926                 data = src[cnt];
 927                 encode(data, dest + to_cnt++);
 928         }
 929 }
 930 
 931 static unsigned long *putsec(int disk, unsigned long *raw, int cnt)
 932 {
 933         struct header hdr;
 934         int i;
 935 
 936         disk&=3;
 937         *raw = (raw[-1]&1) ? 0x2AAAAAAA : 0xAAAAAAAA;
 938         raw++;
 939         *raw++ = 0x44894489;
 940 
 941         hdr.magic = 0xFF;
 942         hdr.track = unit[disk].track;
 943         hdr.sect = cnt;
 944         hdr.ord = unit[disk].dtype->sects * unit[disk].type->sect_mult - cnt;
 945         for (i = 0; i < 16; i++)
 946                 hdr.labels[i] = 0;
 947         hdr.hdrchk = checksum((ulong *)&hdr,
 948                               (char *)&hdr.hdrchk-(char *)&hdr);
 949         hdr.datachk = checksum((ulong *)(unit[disk].trackbuf+cnt*512), 512);
 950 
 951         encode_block(raw, (ulong *)&hdr.magic, 4);
 952         raw += 2;
 953         encode_block(raw, (ulong *)&hdr.labels, 16);
 954         raw += 8;
 955         encode_block(raw, (ulong *)&hdr.hdrchk, 4);
 956         raw += 2;
 957         encode_block(raw, (ulong *)&hdr.datachk, 4);
 958         raw += 2;
 959         encode_block(raw, (ulong *)(unit[disk].trackbuf+cnt*512), 512);
 960         raw += 256;
 961 
 962         return raw;
 963 }
 964 
 965 static void amiga_write(int disk)
 966 {
 967         unsigned int cnt;
 968         unsigned long *ptr = (unsigned long *)raw_buf;
 969 
 970         disk&=3;
 971         /* gap space */
 972         for (cnt = 0; cnt < 415 * unit[disk].type->sect_mult; cnt++)
 973                 *ptr++ = 0xaaaaaaaa;
 974 
 975         /* sectors */
 976         for (cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
 977                 ptr = putsec (disk, ptr, cnt);
 978         *(ushort *)ptr = (ptr[-1]&1) ? 0x2AA8 : 0xAAA8;
 979 }
 980 
 981 
 982 struct dos_header {
 983         unsigned char track,   /* 0-80 */
 984                 side,    /* 0-1 */
 985                 sec,     /* 0-...*/
 986                 len_desc;/* 2 */
 987         unsigned short crc;     /* on 68000 we got an alignment problem, 
 988                                    but this compiler solves it  by adding silently 
 989                                    adding a pad byte so data won't fit
 990                                    and this took about 3h to discover.... */
 991         unsigned char gap1[22];     /* for longword-alignedness (0x4e) */
 992 };
 993 
 994 /* crc routines are borrowed from the messydos-handler  */
 995 
 996 /* excerpt from the messydos-device           
 997 ; The CRC is computed not only over the actual data, but including
 998 ; the SYNC mark (3 * $a1) and the 'ID/DATA - Address Mark' ($fe/$fb).
 999 ; As we don't read or encode these fields into our buffers, we have to
1000 ; preload the registers containing the CRC with the values they would have
1001 ; after stepping over these fields.
1002 ;
1003 ; How CRCs "really" work:
1004 ;
1005 ; First, you should regard a bitstring as a series of coefficients of
1006 ; polynomials. We calculate with these polynomials in modulo-2
1007 ; arithmetic, in which both add and subtract are done the same as
1008 ; exclusive-or. Now, we modify our data (a very long polynomial) in
1009 ; such a way that it becomes divisible by the CCITT-standard 16-bit
1010 ;                16   12   5
1011 ; polynomial:   x  + x  + x + 1, represented by $11021. The easiest
1012 ; way to do this would be to multiply (using proper arithmetic) our
1013 ; datablock with $11021. So we have:
1014 ;   data * $11021                =
1015 ;   data * ($10000 + $1021)      =
1016 ;   data * $10000 + data * $1021
1017 ; The left part of this is simple: Just add two 0 bytes. But then
1018 ; the right part (data $1021) remains difficult and even could have
1019 ; a carry into the left part. The solution is to use a modified
1020 ; multiplication, which has a result that is not correct, but with
1021 ; a difference of any multiple of $11021. We then only need to keep
1022 ; the 16 least significant bits of the result.
1023 ;
1024 ; The following algorithm does this for us:
1025 ;
1026 ;   unsigned char *data, c, crclo, crchi;
1027 ;   while (not done) {
1028 ;       c = *data++ + crchi;
1029 ;       crchi = (@ c) >> 8 + crclo;
1030 ;       crclo = @ c;
1031 ;   }
1032 ;
1033 ; Remember, + is done with EOR, the @ operator is in two tables (high
1034 ; and low byte separately), which is calculated as
1035 ;
1036 ;      $1021 * (c & $F0)
1037 ;  xor $1021 * (c & $0F)
1038 ;  xor $1021 * (c >> 4)         (* is regular multiplication)
1039 ;
1040 ;
1041 ; Anyway, the end result is the same as the remainder of the division of
1042 ; the data by $11021. I am afraid I need to study theory a bit more...
1043 
1044 
1045 my only works was to code this from manx to C....
1046 
1047 */
1048 
1049 static ushort dos_crc(void * data_a3, int data_d0, int data_d1, int data_d3)
1050 {
1051         static unsigned char CRCTable1[] = {
1052                 0x00,0x10,0x20,0x30,0x40,0x50,0x60,0x70,0x81,0x91,0xa1,0xb1,0xc1,0xd1,0xe1,0xf1,
1053                 0x12,0x02,0x32,0x22,0x52,0x42,0x72,0x62,0x93,0x83,0xb3,0xa3,0xd3,0xc3,0xf3,0xe3,
1054                 0x24,0x34,0x04,0x14,0x64,0x74,0x44,0x54,0xa5,0xb5,0x85,0x95,0xe5,0xf5,0xc5,0xd5,
1055                 0x36,0x26,0x16,0x06,0x76,0x66,0x56,0x46,0xb7,0xa7,0x97,0x87,0xf7,0xe7,0xd7,0xc7,
1056                 0x48,0x58,0x68,0x78,0x08,0x18,0x28,0x38,0xc9,0xd9,0xe9,0xf9,0x89,0x99,0xa9,0xb9,
1057                 0x5a,0x4a,0x7a,0x6a,0x1a,0x0a,0x3a,0x2a,0xdb,0xcb,0xfb,0xeb,0x9b,0x8b,0xbb,0xab,
1058                 0x6c,0x7c,0x4c,0x5c,0x2c,0x3c,0x0c,0x1c,0xed,0xfd,0xcd,0xdd,0xad,0xbd,0x8d,0x9d,
1059                 0x7e,0x6e,0x5e,0x4e,0x3e,0x2e,0x1e,0x0e,0xff,0xef,0xdf,0xcf,0xbf,0xaf,0x9f,0x8f,
1060                 0x91,0x81,0xb1,0xa1,0xd1,0xc1,0xf1,0xe1,0x10,0x00,0x30,0x20,0x50,0x40,0x70,0x60,
1061                 0x83,0x93,0xa3,0xb3,0xc3,0xd3,0xe3,0xf3,0x02,0x12,0x22,0x32,0x42,0x52,0x62,0x72,
1062                 0xb5,0xa5,0x95,0x85,0xf5,0xe5,0xd5,0xc5,0x34,0x24,0x14,0x04,0x74,0x64,0x54,0x44,
1063                 0xa7,0xb7,0x87,0x97,0xe7,0xf7,0xc7,0xd7,0x26,0x36,0x06,0x16,0x66,0x76,0x46,0x56,
1064                 0xd9,0xc9,0xf9,0xe9,0x99,0x89,0xb9,0xa9,0x58,0x48,0x78,0x68,0x18,0x08,0x38,0x28,
1065                 0xcb,0xdb,0xeb,0xfb,0x8b,0x9b,0xab,0xbb,0x4a,0x5a,0x6a,0x7a,0x0a,0x1a,0x2a,0x3a,
1066                 0xfd,0xed,0xdd,0xcd,0xbd,0xad,0x9d,0x8d,0x7c,0x6c,0x5c,0x4c,0x3c,0x2c,0x1c,0x0c,
1067                 0xef,0xff,0xcf,0xdf,0xaf,0xbf,0x8f,0x9f,0x6e,0x7e,0x4e,0x5e,0x2e,0x3e,0x0e,0x1e
1068         };
1069 
1070         static unsigned char CRCTable2[] = {
1071                 0x00,0x21,0x42,0x63,0x84,0xa5,0xc6,0xe7,0x08,0x29,0x4a,0x6b,0x8c,0xad,0xce,0xef,
1072                 0x31,0x10,0x73,0x52,0xb5,0x94,0xf7,0xd6,0x39,0x18,0x7b,0x5a,0xbd,0x9c,0xff,0xde,
1073                 0x62,0x43,0x20,0x01,0xe6,0xc7,0xa4,0x85,0x6a,0x4b,0x28,0x09,0xee,0xcf,0xac,0x8d,
1074                 0x53,0x72,0x11,0x30,0xd7,0xf6,0x95,0xb4,0x5b,0x7a,0x19,0x38,0xdf,0xfe,0x9d,0xbc,
1075                 0xc4,0xe5,0x86,0xa7,0x40,0x61,0x02,0x23,0xcc,0xed,0x8e,0xaf,0x48,0x69,0x0a,0x2b,
1076                 0xf5,0xd4,0xb7,0x96,0x71,0x50,0x33,0x12,0xfd,0xdc,0xbf,0x9e,0x79,0x58,0x3b,0x1a,
1077                 0xa6,0x87,0xe4,0xc5,0x22,0x03,0x60,0x41,0xae,0x8f,0xec,0xcd,0x2a,0x0b,0x68,0x49,
1078                 0x97,0xb6,0xd5,0xf4,0x13,0x32,0x51,0x70,0x9f,0xbe,0xdd,0xfc,0x1b,0x3a,0x59,0x78,
1079                 0x88,0xa9,0xca,0xeb,0x0c,0x2d,0x4e,0x6f,0x80,0xa1,0xc2,0xe3,0x04,0x25,0x46,0x67,
1080                 0xb9,0x98,0xfb,0xda,0x3d,0x1c,0x7f,0x5e,0xb1,0x90,0xf3,0xd2,0x35,0x14,0x77,0x56,
1081                 0xea,0xcb,0xa8,0x89,0x6e,0x4f,0x2c,0x0d,0xe2,0xc3,0xa0,0x81,0x66,0x47,0x24,0x05,
1082                 0xdb,0xfa,0x99,0xb8,0x5f,0x7e,0x1d,0x3c,0xd3,0xf2,0x91,0xb0,0x57,0x76,0x15,0x34,
1083                 0x4c,0x6d,0x0e,0x2f,0xc8,0xe9,0x8a,0xab,0x44,0x65,0x06,0x27,0xc0,0xe1,0x82,0xa3,
1084                 0x7d,0x5c,0x3f,0x1e,0xf9,0xd8,0xbb,0x9a,0x75,0x54,0x37,0x16,0xf1,0xd0,0xb3,0x92,
1085                 0x2e,0x0f,0x6c,0x4d,0xaa,0x8b,0xe8,0xc9,0x26,0x07,0x64,0x45,0xa2,0x83,0xe0,0xc1,
1086                 0x1f,0x3e,0x5d,0x7c,0x9b,0xba,0xd9,0xf8,0x17,0x36,0x55,0x74,0x93,0xb2,0xd1,0xf0
1087         };
1088 
1089 /* look at the asm-code - what looks in C a bit strange is almost as good as handmade */
1090         register int i;
1091         register unsigned char *CRCT1, *CRCT2, *data, c, crch, crcl;
1092 
1093         CRCT1=CRCTable1;
1094         CRCT2=CRCTable2;
1095         data=data_a3;
1096         crcl=data_d1;
1097         crch=data_d0;
1098         for (i=data_d3; i>=0; i--) {
1099                 c = (*data++) ^ crch;
1100                 crch = CRCT1[c] ^ crcl;
1101                 crcl = CRCT2[c];
1102         }
1103         return (crch<<8)|crcl;
1104 }
1105 
1106 static inline ushort dos_hdr_crc (struct dos_header *hdr)
1107 {
1108         return dos_crc(&(hdr->track), 0xb2, 0x30, 3); /* precomputed magic */
1109 }
1110 
1111 static inline ushort dos_data_crc(unsigned char *data)
1112 {
1113         return dos_crc(data, 0xe2, 0x95 ,511); /* precomputed magic */
1114 }
1115 
1116 static inline unsigned char dos_decode_byte(ushort word)
1117 {
1118         register ushort w2;
1119         register unsigned char byte;
1120         register unsigned char *dec = mfmdecode;
1121 
1122         w2=word;
1123         w2>>=8;
1124         w2&=127;
1125         byte = dec[w2];
1126         byte <<= 4;
1127         w2 = word & 127;
1128         byte |= dec[w2];
1129         return byte;
1130 }
1131 
1132 static unsigned long dos_decode(unsigned char *data, unsigned short *raw, int len)
1133 {
1134         int i;
1135 
1136         for (i = 0; i < len; i++)
1137                 *data++=dos_decode_byte(*raw++);
1138         return ((ulong)raw);
1139 }
1140 
1141 #ifdef DEBUG
1142 static void dbg(unsigned long ptr)
1143 {
1144         printk("raw data @%08lx: %08lx, %08lx ,%08lx, %08lx\n", ptr,
1145                ((ulong *)ptr)[0], ((ulong *)ptr)[1],
1146                ((ulong *)ptr)[2], ((ulong *)ptr)[3]);
1147 }
1148 #endif
1149 
1150 static int dos_read(int drive)
1151 {
1152         unsigned long end;
1153         unsigned long raw;
1154         int scnt;
1155         unsigned short crc,data_crc[2];
1156         struct dos_header hdr;
1157 
1158         drive&=3;
1159         raw = (long) raw_buf;
1160         end = raw + unit[drive].type->read_size;
1161 
1162         for (scnt=0; scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
1163                 do { /* search for the right sync of each sec-hdr */
1164                         if (!(raw = scan_sync (raw, end))) {
1165                                 printk(KERN_INFO "dos_read: no hdr sync on "
1166                                        "track %d, unit %d for sector %d\n",
1167                                        unit[drive].track,drive,scnt);
1168                                 return MFM_NOSYNC;
1169                         }
1170 #ifdef DEBUG
1171                         dbg(raw);
1172 #endif
1173                 } while (*((ushort *)raw)!=0x5554); /* loop usually only once done */
1174                 raw+=2; /* skip over headermark */
1175                 raw = dos_decode((unsigned char *)&hdr,(ushort *) raw,8);
1176                 crc = dos_hdr_crc(&hdr);
1177 
1178 #ifdef DEBUG
1179                 printk("(%3d,%d,%2d,%d) %x\n", hdr.track, hdr.side,
1180                        hdr.sec, hdr.len_desc, hdr.crc);
1181 #endif
1182 
1183                 if (crc != hdr.crc) {
1184                         printk(KERN_INFO "dos_read: MFM_HEADER %04x,%04x\n",
1185                                hdr.crc, crc);
1186                         return MFM_HEADER;
1187                 }
1188                 if (hdr.track != unit[drive].track/unit[drive].type->heads) {
1189                         printk(KERN_INFO "dos_read: MFM_TRACK %d, %d\n",
1190                                hdr.track,
1191                                unit[drive].track/unit[drive].type->heads);
1192                         return MFM_TRACK;
1193                 }
1194 
1195                 if (hdr.side != unit[drive].track%unit[drive].type->heads) {
1196                         printk(KERN_INFO "dos_read: MFM_SIDE %d, %d\n",
1197                                hdr.side,
1198                                unit[drive].track%unit[drive].type->heads);
1199                         return MFM_TRACK;
1200                 }
1201 
1202                 if (hdr.len_desc != 2) {
1203                         printk(KERN_INFO "dos_read: unknown sector len "
1204                                "descriptor %d\n", hdr.len_desc);
1205                         return MFM_DATA;
1206                 }
1207 #ifdef DEBUG
1208                 printk("hdr accepted\n");
1209 #endif
1210                 if (!(raw = scan_sync (raw, end))) {
1211                         printk(KERN_INFO "dos_read: no data sync on track "
1212                                "%d, unit %d for sector%d, disk sector %d\n",
1213                                unit[drive].track, drive, scnt, hdr.sec);
1214                         return MFM_NOSYNC;
1215                 }
1216 #ifdef DEBUG
1217                 dbg(raw);
1218 #endif
1219 
1220                 if (*((ushort *)raw)!=0x5545) {
1221                         printk(KERN_INFO "dos_read: no data mark after "
1222                                "sync (%d,%d,%d,%d) sc=%d\n",
1223                                hdr.track,hdr.side,hdr.sec,hdr.len_desc,scnt);
1224                         return MFM_NOSYNC;
1225                 }
1226 
1227                 raw+=2;  /* skip data mark (included in checksum) */
1228                 raw = dos_decode((unsigned char *)(unit[drive].trackbuf + (hdr.sec - 1) * 512), (ushort *) raw, 512);
1229                 raw = dos_decode((unsigned char  *)data_crc,(ushort *) raw,4);
1230                 crc = dos_data_crc(unit[drive].trackbuf + (hdr.sec - 1) * 512);
1231 
1232                 if (crc != data_crc[0]) {
1233                         printk(KERN_INFO "dos_read: MFM_DATA (%d,%d,%d,%d) "
1234                                "sc=%d, %x %x\n", hdr.track, hdr.side,
1235                                hdr.sec, hdr.len_desc, scnt,data_crc[0], crc);
1236                         printk(KERN_INFO "data=(%lx,%lx,%lx,%lx,...)\n",
1237                                ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[0],
1238                                ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[1],
1239                                ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[2],
1240                                ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[3]);
1241                         return MFM_DATA;
1242                 }
1243         }
1244         return 0;
1245 }
1246 
1247 static inline ushort dos_encode_byte(unsigned char byte)
1248 {
1249         register unsigned char *enc, b2, b1;
1250         register ushort word;
1251 
1252         enc=mfmencode;
1253         b1=byte;
1254         b2=b1>>4;
1255         b1&=15;
1256         word=enc[b2] <<8 | enc [b1];
1257         return (word|((word&(256|64)) ? 0: 128));
1258 }
1259 
1260 static void dos_encode_block(ushort *dest, unsigned char *src, int len)
1261 {
1262         int i;
1263 
1264         for (i = 0; i < len; i++) {
1265                 *dest=dos_encode_byte(*src++);
1266                 *dest|=((dest[-1]&1)||(*dest&0x4000))? 0: 0x8000;
1267                 dest++;
1268         }
1269 }
1270 
1271 static unsigned long *ms_putsec(int drive, unsigned long *raw, int cnt)
1272 {
1273         static struct dos_header hdr={0,0,0,2,0,
1274           {78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78}};
1275         int i;
1276         static ushort crc[2]={0,0x4e4e};
1277 
1278         drive&=3;
1279 /* id gap 1 */
1280 /* the MFM word before is always 9254 */
1281         for(i=0;i<6;i++)
1282                 *raw++=0xaaaaaaaa;
1283 /* 3 sync + 1 headermark */
1284         *raw++=0x44894489;
1285         *raw++=0x44895554;
1286 
1287 /* fill in the variable parts of the header */
1288         hdr.track=unit[drive].track/unit[drive].type->heads;
1289         hdr.side=unit[drive].track%unit[drive].type->heads;
1290         hdr.sec=cnt+1;
1291         hdr.crc=dos_hdr_crc(&hdr);
1292 
1293 /* header (without "magic") and id gap 2*/
1294         dos_encode_block((ushort *)raw,(unsigned char *) &hdr.track,28);
1295         raw+=14;
1296 
1297 /*id gap 3 */
1298         for(i=0;i<6;i++)
1299                 *raw++=0xaaaaaaaa;
1300 
1301 /* 3 syncs and 1 datamark */
1302         *raw++=0x44894489;
1303         *raw++=0x44895545;
1304 
1305 /* data */
1306         dos_encode_block((ushort *)raw,
1307                          (unsigned char *)unit[drive].trackbuf+cnt*512,512);
1308         raw+=256;
1309 
1310 /*data crc + jd's special gap (long words :-/) */
1311         crc[0]=dos_data_crc(unit[drive].trackbuf+cnt*512);
1312         dos_encode_block((ushort *) raw,(unsigned char *)crc,4);
1313         raw+=2;
1314 
1315 /* data gap */
1316         for(i=0;i<38;i++)
1317                 *raw++=0x92549254;
1318 
1319         return raw; /* wrote 652 MFM words */
1320 }
1321 
1322 static void dos_write(int disk)
1323 {
1324         int cnt;
1325         unsigned long raw = (unsigned long) raw_buf;
1326         unsigned long *ptr=(unsigned long *)raw;
1327 
1328         disk&=3;
1329 /* really gap4 + indexgap , but we write it first and round it up */
1330         for (cnt=0;cnt<425;cnt++)
1331                 *ptr++=0x92549254;
1332 
1333 /* the following is just guessed */
1334         if (unit[disk].type->sect_mult==2)  /* check for HD-Disks */
1335                 for(cnt=0;cnt<473;cnt++)
1336                         *ptr++=0x92549254;
1337 
1338 /* now the index marks...*/
1339         for (cnt=0;cnt<20;cnt++)
1340                 *ptr++=0x92549254;
1341         for (cnt=0;cnt<6;cnt++)
1342                 *ptr++=0xaaaaaaaa;
1343         *ptr++=0x52245224;
1344         *ptr++=0x52245552;
1345         for (cnt=0;cnt<20;cnt++)
1346                 *ptr++=0x92549254;
1347 
1348 /* sectors */
1349         for(cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
1350                 ptr=ms_putsec(disk,ptr,cnt);
1351 
1352         *(ushort *)ptr = 0xaaa8; /* MFM word before is always 0x9254 */
1353 }
1354 
1355 /*
1356  * Here comes the high level stuff (i.e. the filesystem interface)
1357  * and helper functions.
1358  * Normally this should be the only part that has to be adapted to
1359  * different kernel versions.
1360  */
1361 
1362 /* FIXME: this assumes the drive is still spinning -
1363  * which is only true if we complete writing a track within three seconds
1364  */
1365 static void flush_track_callback(struct timer_list *timer)
1366 {
1367         unsigned long nr = ((unsigned long)timer -
1368                                (unsigned long)&flush_track_timer[0]) /
1369                                         sizeof(flush_track_timer[0]);
1370 
1371         nr&=3;
1372         writefromint = 1;
1373         if (!try_fdc(nr)) {
1374                 /* we might block in an interrupt, so try again later */
1375                 flush_track_timer[nr].expires = jiffies + 1;
1376                 add_timer(flush_track_timer + nr);
1377                 return;
1378         }
1379         get_fdc(nr);
1380         (*unit[nr].dtype->write_fkt)(nr);
1381         if (!raw_write(nr)) {
1382                 printk (KERN_NOTICE "floppy disk write protected\n");
1383                 writefromint = 0;
1384                 writepending = 0;
1385         }
1386         rel_fdc();
1387 }
1388 
1389 static int non_int_flush_track (unsigned long nr)
1390 {
1391         unsigned long flags;
1392 
1393         nr&=3;
1394         writefromint = 0;
1395         del_timer(&post_write_timer);
1396         get_fdc(nr);
1397         if (!fd_motor_on(nr)) {
1398                 writepending = 0;
1399                 rel_fdc();
1400                 return 0;
1401         }
1402         local_irq_save(flags);
1403         if (writepending != 2) {
1404                 local_irq_restore(flags);
1405                 (*unit[nr].dtype->write_fkt)(nr);
1406                 if (!raw_write(nr)) {
1407                         printk (KERN_NOTICE "floppy disk write protected "
1408                                 "in write!\n");
1409                         writepending = 0;
1410                         return 0;
1411                 }
1412                 wait_event(wait_fd_block, block_flag != 2);
1413         }
1414         else {
1415                 local_irq_restore(flags);
1416                 ms_delay(2); /* 2 ms post_write delay */
1417                 post_write(nr);
1418         }
1419         rel_fdc();
1420         return 1;
1421 }
1422 
1423 static int get_track(int drive, int track)
1424 {
1425         int error, errcnt;
1426 
1427         drive&=3;
1428         if (unit[drive].track == track)
1429                 return 0;
1430         get_fdc(drive);
1431         if (!fd_motor_on(drive)) {
1432                 rel_fdc();
1433                 return -1;
1434         }
1435 
1436         if (unit[drive].dirty == 1) {
1437                 del_timer (flush_track_timer + drive);
1438                 non_int_flush_track (drive);
1439         }
1440         errcnt = 0;
1441         while (errcnt < MAX_ERRORS) {
1442                 if (!fd_seek(drive, track))
1443                         return -1;
1444                 raw_read(drive);
1445                 error = (*unit[drive].dtype->read_fkt)(drive);
1446                 if (error == 0) {
1447                         rel_fdc();
1448                         return 0;
1449                 }
1450                 /* Read Error Handling: recalibrate and try again */
1451                 unit[drive].track = -1;
1452                 errcnt++;
1453         }
1454         rel_fdc();
1455         return -1;
1456 }
1457 
1458 static blk_status_t amiflop_rw_cur_segment(struct amiga_floppy_struct *floppy,
1459                                            struct request *rq)
1460 {
1461         int drive = floppy - unit;
1462         unsigned int cnt, block, track, sector;
1463         char *data;
1464 
1465         for (cnt = 0; cnt < blk_rq_cur_sectors(rq); cnt++) {
1466 #ifdef DEBUG
1467                 printk("fd: sector %ld + %d requested for %s\n",
1468                        blk_rq_pos(rq), cnt,
1469                        (rq_data_dir(rq) == READ) ? "read" : "write");
1470 #endif
1471                 block = blk_rq_pos(rq) + cnt;
1472                 track = block / (floppy->dtype->sects * floppy->type->sect_mult);
1473                 sector = block % (floppy->dtype->sects * floppy->type->sect_mult);
1474                 data = bio_data(rq->bio) + 512 * cnt;
1475 #ifdef DEBUG
1476                 printk("access to track %d, sector %d, with buffer at "
1477                        "0x%08lx\n", track, sector, data);
1478 #endif
1479 
1480                 if (get_track(drive, track) == -1)
1481                         return BLK_STS_IOERR;
1482 
1483                 if (rq_data_dir(rq) == READ) {
1484                         memcpy(data, floppy->trackbuf + sector * 512, 512);
1485                 } else {
1486                         memcpy(floppy->trackbuf + sector * 512, data, 512);
1487 
1488                         /* keep the drive spinning while writes are scheduled */
1489                         if (!fd_motor_on(drive))
1490                                 return BLK_STS_IOERR;
1491                         /*
1492                          * setup a callback to write the track buffer
1493                          * after a short (1 tick) delay.
1494                          */
1495                         floppy->dirty = 1;
1496                         /* reset the timer */
1497                         mod_timer (flush_track_timer + drive, jiffies + 1);
1498                 }
1499         }
1500 
1501         return BLK_STS_OK;
1502 }
1503 
1504 static blk_status_t amiflop_queue_rq(struct blk_mq_hw_ctx *hctx,
1505                                      const struct blk_mq_queue_data *bd)
1506 {
1507         struct request *rq = bd->rq;
1508         struct amiga_floppy_struct *floppy = rq->rq_disk->private_data;
1509         blk_status_t err;
1510 
1511         if (!spin_trylock_irq(&amiflop_lock))
1512                 return BLK_STS_DEV_RESOURCE;
1513 
1514         blk_mq_start_request(rq);
1515 
1516         do {
1517                 err = amiflop_rw_cur_segment(floppy, rq);
1518         } while (blk_update_request(rq, err, blk_rq_cur_bytes(rq)));
1519         blk_mq_end_request(rq, err);
1520 
1521         spin_unlock_irq(&amiflop_lock);
1522         return BLK_STS_OK;
1523 }
1524 
1525 static int fd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1526 {
1527         int drive = MINOR(bdev->bd_dev) & 3;
1528 
1529         geo->heads = unit[drive].type->heads;
1530         geo->sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;
1531         geo->cylinders = unit[drive].type->tracks;
1532         return 0;
1533 }
1534 
1535 static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
1536                     unsigned int cmd, unsigned long param)
1537 {
1538         struct amiga_floppy_struct *p = bdev->bd_disk->private_data;
1539         int drive = p - unit;
1540         static struct floppy_struct getprm;
1541         void __user *argp = (void __user *)param;
1542 
1543         switch(cmd){
1544         case FDFMTBEG:
1545                 get_fdc(drive);
1546                 if (fd_ref[drive] > 1) {
1547                         rel_fdc();
1548                         return -EBUSY;
1549                 }
1550                 fsync_bdev(bdev);
1551                 if (fd_motor_on(drive) == 0) {
1552                         rel_fdc();
1553                         return -ENODEV;
1554                 }
1555                 if (fd_calibrate(drive) == 0) {
1556                         rel_fdc();
1557                         return -ENXIO;
1558                 }
1559                 floppy_off(drive);
1560                 rel_fdc();
1561                 break;
1562         case FDFMTTRK:
1563                 if (param < p->type->tracks * p->type->heads)
1564                 {
1565                         get_fdc(drive);
1566                         if (fd_seek(drive,param) != 0){
1567                                 memset(p->trackbuf, FD_FILL_BYTE,
1568                                        p->dtype->sects * p->type->sect_mult * 512);
1569                                 non_int_flush_track(drive);
1570                         }
1571                         floppy_off(drive);
1572                         rel_fdc();
1573                 }
1574                 else
1575                         return -EINVAL;
1576                 break;
1577         case FDFMTEND:
1578                 floppy_off(drive);
1579                 invalidate_bdev(bdev);
1580                 break;
1581         case FDGETPRM:
1582                 memset((void *)&getprm, 0, sizeof (getprm));
1583                 getprm.track=p->type->tracks;
1584                 getprm.head=p->type->heads;
1585                 getprm.sect=p->dtype->sects * p->type->sect_mult;
1586                 getprm.size=p->blocks;
1587                 if (copy_to_user(argp, &getprm, sizeof(struct floppy_struct)))
1588                         return -EFAULT;
1589                 break;
1590         case FDSETPRM:
1591         case FDDEFPRM:
1592                 return -EINVAL;
1593         case FDFLUSH: /* unconditionally, even if not needed */
1594                 del_timer (flush_track_timer + drive);
1595                 non_int_flush_track(drive);
1596                 break;
1597 #ifdef RAW_IOCTL
1598         case IOCTL_RAW_TRACK:
1599                 if (copy_to_user(argp, raw_buf, p->type->read_size))
1600                         return -EFAULT;
1601                 else
1602                         return p->type->read_size;
1603 #endif
1604         default:
1605                 return -ENOSYS;
1606         }
1607         return 0;
1608 }
1609 
1610 static int fd_ioctl(struct block_device *bdev, fmode_t mode,
1611                              unsigned int cmd, unsigned long param)
1612 {
1613         int ret;
1614 
1615         mutex_lock(&amiflop_mutex);
1616         ret = fd_locked_ioctl(bdev, mode, cmd, param);
1617         mutex_unlock(&amiflop_mutex);
1618 
1619         return ret;
1620 }
1621 
1622 static void fd_probe(int dev)
1623 {
1624         unsigned long code;
1625         int type;
1626         int drive;
1627 
1628         drive = dev & 3;
1629         code = fd_get_drive_id(drive);
1630 
1631         /* get drive type */
1632         for (type = 0; type < num_dr_types; type++)
1633                 if (drive_types[type].code == code)
1634                         break;
1635 
1636         if (type >= num_dr_types) {
1637                 printk(KERN_WARNING "fd_probe: unsupported drive type "
1638                        "%08lx found\n", code);
1639                 unit[drive].type = &drive_types[num_dr_types-1]; /* FD_NODRIVE */
1640                 return;
1641         }
1642 
1643         unit[drive].type = drive_types + type;
1644         unit[drive].track = -1;
1645 
1646         unit[drive].disk = -1;
1647         unit[drive].motor = 0;
1648         unit[drive].busy = 0;
1649         unit[drive].status = -1;
1650 }
1651 
1652 /*
1653  * floppy_open check for aliasing (/dev/fd0 can be the same as
1654  * /dev/PS0 etc), and disallows simultaneous access to the same
1655  * drive with different device numbers.
1656  */
1657 static int floppy_open(struct block_device *bdev, fmode_t mode)
1658 {
1659         int drive = MINOR(bdev->bd_dev) & 3;
1660         int system =  (MINOR(bdev->bd_dev) & 4) >> 2;
1661         int old_dev;
1662         unsigned long flags;
1663 
1664         mutex_lock(&amiflop_mutex);
1665         old_dev = fd_device[drive];
1666 
1667         if (fd_ref[drive] && old_dev != system) {
1668                 mutex_unlock(&amiflop_mutex);
1669                 return -EBUSY;
1670         }
1671 
1672         if (mode & (FMODE_READ|FMODE_WRITE)) {
1673                 check_disk_change(bdev);
1674                 if (mode & FMODE_WRITE) {
1675                         int wrprot;
1676 
1677                         get_fdc(drive);
1678                         fd_select (drive);
1679                         wrprot = !(ciaa.pra & DSKPROT);
1680                         fd_deselect (drive);
1681                         rel_fdc();
1682 
1683                         if (wrprot) {
1684                                 mutex_unlock(&amiflop_mutex);
1685                                 return -EROFS;
1686                         }
1687                 }
1688         }
1689 
1690         local_irq_save(flags);
1691         fd_ref[drive]++;
1692         fd_device[drive] = system;
1693         local_irq_restore(flags);
1694 
1695         unit[drive].dtype=&data_types[system];
1696         unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
1697                 data_types[system].sects*unit[drive].type->sect_mult;
1698         set_capacity(unit[drive].gendisk, unit[drive].blocks);
1699 
1700         printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
1701                unit[drive].type->name, data_types[system].name);
1702 
1703         mutex_unlock(&amiflop_mutex);
1704         return 0;
1705 }
1706 
1707 static void floppy_release(struct gendisk *disk, fmode_t mode)
1708 {
1709         struct amiga_floppy_struct *p = disk->private_data;
1710         int drive = p - unit;
1711 
1712         mutex_lock(&amiflop_mutex);
1713         if (unit[drive].dirty == 1) {
1714                 del_timer (flush_track_timer + drive);
1715                 non_int_flush_track (drive);
1716         }
1717   
1718         if (!fd_ref[drive]--) {
1719                 printk(KERN_CRIT "floppy_release with fd_ref == 0");
1720                 fd_ref[drive] = 0;
1721         }
1722 #ifdef MODULE
1723         floppy_off (drive);
1724 #endif
1725         mutex_unlock(&amiflop_mutex);
1726 }
1727 
1728 /*
1729  * check_events is never called from an interrupt, so we can relax a bit
1730  * here, sleep etc. Note that floppy-on tries to set current_DOR to point
1731  * to the desired drive, but it will probably not survive the sleep if
1732  * several floppies are used at the same time: thus the loop.
1733  */
1734 static unsigned amiga_check_events(struct gendisk *disk, unsigned int clearing)
1735 {
1736         struct amiga_floppy_struct *p = disk->private_data;
1737         int drive = p - unit;
1738         int changed;
1739         static int first_time = 1;
1740 
1741         if (first_time)
1742                 changed = first_time--;
1743         else {
1744                 get_fdc(drive);
1745                 fd_select (drive);
1746                 changed = !(ciaa.pra & DSKCHANGE);
1747                 fd_deselect (drive);
1748                 rel_fdc();
1749         }
1750 
1751         if (changed) {
1752                 fd_probe(drive);
1753                 p->track = -1;
1754                 p->dirty = 0;
1755                 writepending = 0; /* if this was true before, too bad! */
1756                 writefromint = 0;
1757                 return DISK_EVENT_MEDIA_CHANGE;
1758         }
1759         return 0;
1760 }
1761 
1762 static const struct block_device_operations floppy_fops = {
1763         .owner          = THIS_MODULE,
1764         .open           = floppy_open,
1765         .release        = floppy_release,
1766         .ioctl          = fd_ioctl,
1767         .getgeo         = fd_getgeo,
1768         .check_events   = amiga_check_events,
1769 };
1770 
1771 static const struct blk_mq_ops amiflop_mq_ops = {
1772         .queue_rq = amiflop_queue_rq,
1773 };
1774 
1775 static struct gendisk *fd_alloc_disk(int drive)
1776 {
1777         struct gendisk *disk;
1778 
1779         disk = alloc_disk(1);
1780         if (!disk)
1781                 goto out;
1782 
1783         disk->queue = blk_mq_init_sq_queue(&unit[drive].tag_set, &amiflop_mq_ops,
1784                                                 2, BLK_MQ_F_SHOULD_MERGE);
1785         if (IS_ERR(disk->queue)) {
1786                 disk->queue = NULL;
1787                 goto out_put_disk;
1788         }
1789 
1790         unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL);
1791         if (!unit[drive].trackbuf)
1792                 goto out_cleanup_queue;
1793 
1794         return disk;
1795 
1796 out_cleanup_queue:
1797         blk_cleanup_queue(disk->queue);
1798         disk->queue = NULL;
1799         blk_mq_free_tag_set(&unit[drive].tag_set);
1800 out_put_disk:
1801         put_disk(disk);
1802 out:
1803         unit[drive].type->code = FD_NODRIVE;
1804         return NULL;
1805 }
1806 
1807 static int __init fd_probe_drives(void)
1808 {
1809         int drive,drives,nomem;
1810 
1811         pr_info("FD: probing units\nfound");
1812         drives=0;
1813         nomem=0;
1814         for(drive=0;drive<FD_MAX_UNITS;drive++) {
1815                 struct gendisk *disk;
1816                 fd_probe(drive);
1817                 if (unit[drive].type->code == FD_NODRIVE)
1818                         continue;
1819 
1820                 disk = fd_alloc_disk(drive);
1821                 if (!disk) {
1822                         pr_cont(" no mem for fd%d", drive);
1823                         nomem = 1;
1824                         continue;
1825                 }
1826                 unit[drive].gendisk = disk;
1827                 drives++;
1828 
1829                 pr_cont(" fd%d",drive);
1830                 disk->major = FLOPPY_MAJOR;
1831                 disk->first_minor = drive;
1832                 disk->fops = &floppy_fops;
1833                 disk->events = DISK_EVENT_MEDIA_CHANGE;
1834                 sprintf(disk->disk_name, "fd%d", drive);
1835                 disk->private_data = &unit[drive];
1836                 set_capacity(disk, 880*2);
1837                 add_disk(disk);
1838         }
1839         if ((drives > 0) || (nomem == 0)) {
1840                 if (drives == 0)
1841                         pr_cont(" no drives");
1842                 pr_cont("\n");
1843                 return drives;
1844         }
1845         pr_cont("\n");
1846         return -ENOMEM;
1847 }
1848  
1849 static struct kobject *floppy_find(dev_t dev, int *part, void *data)
1850 {
1851         int drive = *part & 3;
1852         if (unit[drive].type->code == FD_NODRIVE)
1853                 return NULL;
1854         *part = 0;
1855         return get_disk_and_module(unit[drive].gendisk);
1856 }
1857 
1858 static int __init amiga_floppy_probe(struct platform_device *pdev)
1859 {
1860         int i, ret;
1861 
1862         if (register_blkdev(FLOPPY_MAJOR,"fd"))
1863                 return -EBUSY;
1864 
1865         ret = -ENOMEM;
1866         raw_buf = amiga_chip_alloc(RAW_BUF_SIZE, "Floppy");
1867         if (!raw_buf) {
1868                 printk("fd: cannot get chip mem buffer\n");
1869                 goto out_blkdev;
1870         }
1871 
1872         ret = -EBUSY;
1873         if (request_irq(IRQ_AMIGA_DSKBLK, fd_block_done, 0, "floppy_dma", NULL)) {
1874                 printk("fd: cannot get irq for dma\n");
1875                 goto out_irq;
1876         }
1877 
1878         if (request_irq(IRQ_AMIGA_CIAA_TB, ms_isr, 0, "floppy_timer", NULL)) {
1879                 printk("fd: cannot get irq for timer\n");
1880                 goto out_irq2;
1881         }
1882 
1883         ret = -ENODEV;
1884         if (fd_probe_drives() < 1) /* No usable drives */
1885                 goto out_probe;
1886 
1887         blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
1888                                 floppy_find, NULL, NULL);
1889 
1890         /* initialize variables */
1891         timer_setup(&motor_on_timer, motor_on_callback, 0);
1892         motor_on_timer.expires = 0;
1893         for (i = 0; i < FD_MAX_UNITS; i++) {
1894                 timer_setup(&motor_off_timer[i], fd_motor_off, 0);
1895                 motor_off_timer[i].expires = 0;
1896                 timer_setup(&flush_track_timer[i], flush_track_callback, 0);
1897                 flush_track_timer[i].expires = 0;
1898 
1899                 unit[i].track = -1;
1900         }
1901 
1902         timer_setup(&post_write_timer, post_write_callback, 0);
1903         post_write_timer.expires = 0;
1904   
1905         for (i = 0; i < 128; i++)
1906                 mfmdecode[i]=255;
1907         for (i = 0; i < 16; i++)
1908                 mfmdecode[mfmencode[i]]=i;
1909 
1910         /* make sure that disk DMA is enabled */
1911         custom.dmacon = DMAF_SETCLR | DMAF_DISK;
1912 
1913         /* init ms timer */
1914         ciaa.crb = 8; /* one-shot, stop */
1915         return 0;
1916 
1917 out_probe:
1918         free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1919 out_irq2:
1920         free_irq(IRQ_AMIGA_DSKBLK, NULL);
1921 out_irq:
1922         amiga_chip_free(raw_buf);
1923 out_blkdev:
1924         unregister_blkdev(FLOPPY_MAJOR,"fd");
1925         return ret;
1926 }
1927 
1928 static struct platform_driver amiga_floppy_driver = {
1929         .driver   = {
1930                 .name   = "amiga-floppy",
1931         },
1932 };
1933 
1934 static int __init amiga_floppy_init(void)
1935 {
1936         return platform_driver_probe(&amiga_floppy_driver, amiga_floppy_probe);
1937 }
1938 
1939 module_init(amiga_floppy_init);
1940 
1941 #ifndef MODULE
1942 static int __init amiga_floppy_setup (char *str)
1943 {
1944         int n;
1945         if (!MACH_IS_AMIGA)
1946                 return 0;
1947         if (!get_option(&str, &n))
1948                 return 0;
1949         printk (KERN_INFO "amiflop: Setting default df0 to %x\n", n);
1950         fd_def_df0 = n;
1951         return 1;
1952 }
1953 
1954 __setup("floppy=", amiga_floppy_setup);
1955 #endif
1956 
1957 MODULE_ALIAS("platform:amiga-floppy");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/block/amiflop.c

DEFINITIONS
