kernel/blk_drv/floppy.c

/* */
This source file includes following definitions.
floppy_deselect
request_done
floppy_change
setup_DMA
output_byte
result
bad_flp_intr
configure_fdc_mode
tell_sector
rw_interrupt
setup_rw_floppy
seek_interrupt
perpendicular_mode
transfer
recal_interrupt
unexpected_floppy_interrupt
recalibrate_floppy
reset_interrupt
reset_floppy
floppy_shutdown
shake_done
retry_recal
shake_zero
shake_one
floppy_on_interrupt
setup_format_params
redo_fd_request
do_fd_request
fd_ioctl
find_base
config_types
floppy_open
floppy_release
ignore_interrupt
floppy_interrupt
floppy_init
   1 /*
   2  *  linux/kernel/floppy.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  */
   6 
   7 /*
   8  * 02.12.91 - Changed to static variables to indicate need for reset
   9  * and recalibrate. This makes some things easier (output_byte reset
  10  * checking etc), and means less interrupt jumping in case of errors,
  11  * so the code is hopefully easier to understand.
  12  */
  13 
  14 /*
  15  * This file is certainly a mess. I've tried my best to get it working,
  16  * but I don't like programming floppies, and I have only one anyway.
  17  * Urgel. I should check for more errors, and do more graceful error
  18  * recovery. Seems there are problems with several drives. I've tried to
  19  * correct them. No promises. 
  20  */
  21 
  22 /*
  23  * As with hd.c, all routines within this file can (and will) be called
  24  * by interrupts, so extreme caution is needed. A hardware interrupt
  25  * handler may not sleep, or a kernel panic will happen. Thus I cannot
  26  * call "floppy-on" directly, but have to set a special timer interrupt
  27  * etc.
  28  */
  29 
  30 /*
  31  * 28.02.92 - made track-buffering routines, based on the routines written
  32  * by entropy@wintermute.wpi.edu (Lawrence Foard). Linus.
  33  */
  34 
  35 /*
  36  * Automatic floppy-detection and formatting written by Werner Almesberger
  37  * (almesber@nessie.cs.id.ethz.ch), who also corrected some problems with
  38  * the floppy-change signal detection.
  39  */
  40 
  41 /*
  42  * 1992/7/22 -- Hennus Bergman: Added better error reporting, fixed 
  43  * FDC data overrun bug, added some preliminary stuff for vertical
  44  * recording support.
  45  * TODO: Errors are still not counted properly.
  46  */
  47 
  48 #define REALLY_SLOW_IO
  49 #define FLOPPY_IRQ 6
  50 
  51 #include <linux/sched.h>
  52 #include <linux/fs.h>
  53 #include <linux/kernel.h>
  54 #include <linux/timer.h>
  55 #include <linux/fdreg.h>
  56 #include <linux/fd.h>
  57 #include <linux/errno.h>
  58 #ifdef HHB_SYSMACROS
  59 #include <linux/system.h>
  60 #endif
  61 
  62 #include <asm/system.h>
  63 #include <asm/io.h>
  64 #include <asm/segment.h>
  65 
  66 #define MAJOR_NR 2
  67 #include "blk.h"
  68 
  69 static unsigned int changed_floppies = 0, fake_change = 0;
  70 
  71 static int recalibrate = 0;
  72 static int reset = 0;
  73 static int recover = 0; /* recalibrate immediately after resetting */
  74 static int seek = 0;
  75 
  76 extern unsigned char current_DOR;
  77 
  78 #define TYPE(x) ((x)>>2)
  79 #define DRIVE(x) ((x)&0x03)
  80 
  81 /*
  82  * Note that MAX_ERRORS=X doesn't imply that we retry every bad read
  83  * max X times - some types of errors increase the errorcount by 2 or
  84  * even 3, so we might actually retry only X/2 times before giving up.
  85  */
  86 #define MAX_ERRORS 12
  87 
  88 /*
  89  * Maximum disk size (in kilobytes). This default is used whenever the
  90  * current disk size is unknown.
  91  */
  92 #define MAX_DISK_SIZE 1440
  93 
  94 /*
  95  * Maximum number of sectors in a track buffer. Track buffering is disabled
  96  * if tracks are bigger.
  97  */
  98 #define MAX_BUFFER_SECTORS 18
  99 
 100 /*
 101  * The DMA channel used by the floppy controller cannot access data at
 102  * addresses >= 1MB
 103  */
 104 #define LAST_DMA_ADDR   (0x100000 - BLOCK_SIZE)
 105 
 106 /*
 107  * globals used by 'result()'
 108  */
 109 #define MAX_REPLIES 7
 110 static unsigned char reply_buffer[MAX_REPLIES];
 111 #define ST0 (reply_buffer[0])
 112 #define ST1 (reply_buffer[1])
 113 #define ST2 (reply_buffer[2])
 114 #define ST3 (reply_buffer[3])
 115 
 116 /*
 117  * This struct defines the different floppy types.
 118  *
 119  * The 'stretch' tells if the tracks need to be doubled for some
 120  * types (ie 360kB diskette in 1.2MB drive etc). Others should
 121  * be self-explanatory.
 122  */
 123 static struct floppy_struct floppy_type[] = {
 124         {    0, 0,0, 0,0,0x00,0x00,0x00,0x00,NULL },    /* no testing */
 125         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,NULL },    /* 360kB PC diskettes */
 126         { 2400,15,2,80,0,0x1B,0x00,0xDF,0x54,NULL },    /* 1.2 MB AT-diskettes */
 127         {  720, 9,2,40,1,0x2A,0x02,0xDF,0x50,NULL },    /* 360kB in 720kB drive */
 128         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,NULL },    /* 3.5" 720kB diskette */
 129         {  720, 9,2,40,1,0x23,0x01,0xDF,0x50,NULL },    /* 360kB in 1.2MB drive */
 130         { 1440, 9,2,80,0,0x23,0x01,0xDF,0x50,NULL },    /* 720kB in 1.2MB drive */
 131         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL },    /* 1.44MB diskette */
 132 };
 133 
 134 /*
 135  * Auto-detection. Each drive type has a pair of formats which are
 136  * used in succession to try to read the disk. If the FDC cannot lock onto
 137  * the disk, the next format is tried. This uses the variable 'probing'.
 138  */
 139 static struct floppy_struct floppy_types[] = {
 140         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,"360k/PC" }, /* 360kB PC diskettes */
 141         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,"360k/PC" }, /* 360kB PC diskettes */
 142         { 2400,15,2,80,0,0x1B,0x00,0xDF,0x54,"1.2M" },    /* 1.2 MB AT-diskettes */
 143         {  720, 9,2,40,1,0x23,0x01,0xDF,0x50,"360k/AT" }, /* 360kB in 1.2MB drive */
 144         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k" },    /* 3.5" 720kB diskette */
 145         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k" },    /* 3.5" 720kB diskette */
 146         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,"1.44M" },   /* 1.44MB diskette */
 147         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k/AT" }, /* 3.5" 720kB diskette */
 148 };
 149 
 150 /* Auto-detection: Disk type used until the next media change occurs. */
 151 struct floppy_struct *current_type[4] = { NULL, NULL, NULL, NULL };
 152 
 153 /* This type is tried first. */
 154 struct floppy_struct *base_type[4];
 155 
 156 /*
 157  * User-provided type information. current_type points to
 158  * the respective entry of this array.
 159  */
 160 struct floppy_struct user_params[4];
 161 
 162 static int floppy_sizes[] ={
 163         MAX_DISK_SIZE, MAX_DISK_SIZE, MAX_DISK_SIZE, MAX_DISK_SIZE,
 164          360, 360 ,360, 360,
 165         1200,1200,1200,1200,
 166          360, 360, 360, 360,
 167          720, 720, 720, 720,
 168          360, 360, 360, 360,
 169          720, 720, 720, 720,
 170         1440,1440,1440,1440
 171 };
 172 
 173 /*
 174  * The driver is trying to determine the correct media format
 175  * while probing is set. rw_interrupt() clears it after a
 176  * successful access.
 177  */
 178 static int probing = 0;
 179 
 180 /*
 181  * (User-provided) media information is _not_ discarded after a media change
 182  * if the corresponding keep_data flag is non-zero. Positive values are
 183  * decremented after each probe.
 184  */
 185 static int keep_data[4] = { 0,0,0,0 };
 186 
 187 /*
 188  * Announce successful media type detection and media information loss after
 189  * disk changes.
 190  */
 191 static ftd_msg[4] = { 0,0,0,0 };
 192 
 193 /* Prevent "aliased" accesses. */
 194 
 195 static fd_ref[4] = { 0,0,0,0 };
 196 static fd_device[4] = { 0,0,0,0 };
 197 
 198 /* Synchronization of FDC access. */
 199 static volatile int format_status = FORMAT_NONE, fdc_busy = 0;
 200 static struct wait_queue *fdc_wait = NULL, *format_done = NULL;
 201 
 202 /* Errors during formatting are counted here. */
 203 static int format_errors;
 204 
 205 /* Format request descriptor. */
 206 static struct format_descr format_req;
 207 
 208 /*
 209  * Current device number. Taken either from the block header or from the
 210  * format request descriptor.
 211  */
 212 #define CURRENT_DEVICE (format_status == FORMAT_BUSY ? format_req.device : \
 213    (CURRENT->dev))
 214 
 215 /* Current error count. */
 216 #define CURRENT_ERRORS (format_status == FORMAT_BUSY ? format_errors : \
 217     (CURRENT->errors))
 218 
 219 /*
 220  * Treshold for reporting FDC errors to the console.
 221  * Setting this to zero may flood your screen when using
 222  * ultra cheap floppies ;-)
 223  */
 224 static unsigned short min_report_error_cnt[4] = {2, 2, 2, 2};
 225 
 226 /*
 227  * Rate is 0 for 500kb/s, 1 for 300kbps, 2 for 250kbps
 228  * Spec1 is 0xSH, where S is stepping rate (F=1ms, E=2ms, D=3ms etc),
 229  * H is head unload time (1=16ms, 2=32ms, etc)
 230  *
 231  * Spec2 is (HLD<<1 | ND), where HLD is head load time (1=2ms, 2=4 ms etc)
 232  * and ND is set means no DMA. Hardcoded to 6 (HLD=6ms, use DMA).
 233  */
 234 
 235 /*
 236  * Track buffer and block buffer (in case track buffering doesn't work).
 237  * Because these are written to by the DMA controller, they must
 238  * not contain a 64k byte boundary crossing, or data will be
 239  * corrupted/lost. Alignment of these is enforced in boot/head.s.
 240  * Note that you must not change the sizes below without updating head.s.
 241  */
 242 extern char tmp_floppy_area[BLOCK_SIZE];
 243 extern char floppy_track_buffer[512*2*MAX_BUFFER_SECTORS];
 244 
 245 static void redo_fd_request(void);
 246 
 247 /*
 248  * These are global variables, as that's the easiest way to give
 249  * information to interrupts. They are the data used for the current
 250  * request.
 251  */
 252 #define NO_TRACK 255
 253 
 254 static int read_track = 0;      /* flag to indicate if we want to read entire track */
 255 static int buffer_track = -1;
 256 static int buffer_drive = -1;
 257 static int cur_spec1 = -1;
 258 static int cur_rate = -1;
 259 static struct floppy_struct * floppy = floppy_type;
 260 static unsigned char current_drive = 255;
 261 static unsigned char sector = 0;
 262 static unsigned char head = 0;
 263 static unsigned char track = 0;
 264 static unsigned char seek_track = 0;
 265 static unsigned char current_track = NO_TRACK;
 266 static unsigned char command = 0;
 267 static unsigned char fdc_version = FDC_TYPE_STD;        /* FDC version code */
 268 unsigned char selected = 0;
 269 struct wait_queue * wait_on_floppy_select = NULL;
 270 
 271 void floppy_deselect(unsigned int nr)
     /*  */
 272 {
 273         if (nr != (current_DOR & 3))
 274                 printk("floppy_deselect: drive not selected\n\r");
 275         selected = 0;
 276         wake_up(&wait_on_floppy_select);
 277 }
 278 
 279 void request_done(int uptodate)
     /*  */
 280 {
 281         timer_active &= ~(1 << FLOPPY_TIMER);
 282         if (format_status != FORMAT_BUSY) end_request(uptodate);
 283         else {
 284                 format_status = uptodate ? FORMAT_OKAY : FORMAT_ERROR;
 285                 wake_up(&format_done);
 286         }
 287 }
 288 
 289 /*
 290  * floppy-change is never called from an interrupt, so we can relax a bit
 291  * here, sleep etc. Note that floppy-on tries to set current_DOR to point
 292  * to the desired drive, but it will probably not survive the sleep if
 293  * several floppies are used at the same time: thus the loop.
 294  */
 295 int floppy_change(struct buffer_head * bh)
     /*  */
 296 {
 297         unsigned int mask = 1 << (bh->b_dev & 0x03);
 298 
 299         if (MAJOR(bh->b_dev) != 2) {
 300                 printk("floppy_changed: not a floppy\r\n");
 301                 return 0;
 302         }
 303         if (fake_change & mask) {
 304                 fake_change &= ~mask;
 305 /* omitting the next line breaks formatting in a horrible way ... */
 306                 changed_floppies &= ~mask;
 307                 return 1;
 308         }
 309         if (changed_floppies & mask) {
 310                 changed_floppies &= ~mask;
 311                 recalibrate = 1;
 312                 return 1;
 313         }
 314         if (!bh)
 315                 return 0;
 316         if (bh->b_dirt)
 317                 ll_rw_block(WRITE,bh);
 318         else {
 319                 buffer_track = -1;
 320                 bh->b_uptodate = 0;
 321                 ll_rw_block(READ,bh);
 322         }
 323         cli();
 324         while (bh->b_lock)
 325                 sleep_on(&bh->b_wait);
 326         sti();
 327         if (changed_floppies & mask) {
 328                 changed_floppies &= ~mask;
 329                 recalibrate = 1;
 330                 return 1;
 331         }
 332         return 0;
 333 }
 334 
 335 #define copy_buffer(from,to) \
 336 __asm__("cld ; rep ; movsl" \
 337         ::"c" (BLOCK_SIZE/4),"S" ((long)(from)),"D" ((long)(to)) \
 338         :"cx","di","si")
 339 
 340 static void setup_DMA(void)
     /*  */
 341 {
 342         unsigned long addr,count;
 343         unsigned char dma_code;
 344 
 345         dma_code = DMA_WRITE;
 346         if (command == FD_READ)
 347                 dma_code = DMA_READ;
 348         if (command == FD_FORMAT) {
 349                 addr = (long) tmp_floppy_area;
 350                 count = floppy->sect*4;
 351         } else {
 352                 addr = (long) CURRENT->buffer;
 353                 count = 1024;
 354         }
 355         if (read_track) {
 356 /* mark buffer-track bad, in case all this fails.. */
 357                 buffer_drive = buffer_track = -1;
 358                 count = floppy->sect*2*512;
 359                 addr = (long) floppy_track_buffer;
 360         } else if (addr >= LAST_DMA_ADDR) {
 361                 addr = (long) tmp_floppy_area;
 362                 if (command == FD_WRITE)
 363                         copy_buffer(CURRENT->buffer,tmp_floppy_area);
 364         }
 365         cli();
 366 #ifndef HHB_SYSMACROS
 367 /* mask DMA 2 */
 368         outb_p(4|2,10);
 369 /* output command byte. I don't know why, but everyone (minix, */
 370 /* sanches & canton) output this twice, first to 12 then to 11 */
 371         outb_p(dma_code,12);
 372         outb_p(dma_code,11);
 373 /* 8 low bits of addr */
 374         outb_p(addr,4);
 375         addr >>= 8;
 376 /* bits 8-15 of addr */
 377         outb_p(addr,4);
 378         addr >>= 8;
 379 /* bits 16-19 of addr */
 380         outb_p(addr,0x81);
 381 /* low 8 bits of count-1 */
 382         count--;
 383         outb_p(count,5);
 384         count >>= 8;
 385 /* high 8 bits of count-1 */
 386         outb_p(count,5);
 387 /* activate DMA 2 */
 388         outb_p(0|2,10);
 389 #else                   /* just to show off my macros -- hhb */
 390         DISABLE_DMA(DMA2);
 391         CLEAR_DMA_FF(DMA2);
 392         SET_DMA_MODE(DMA2, (command == FD_READ)? DMA_MODE_READ : DMA_MODE_WRITE);
 393         SET_DMA_ADDR(DMA2, addr);
 394         SET_DMA_COUNT(DMA2, count);
 395         ENABLE_DMA(DMA2);
 396 #endif
 397         sti();
 398 }
 399 
 400 static void output_byte(char byte)
     /*  */
 401 {
 402         int counter;
 403         unsigned char status;
 404 
 405         if (reset)
 406                 return;
 407         for(counter = 0 ; counter < 10000 ; counter++) {
 408                 status = inb_p(FD_STATUS) & (STATUS_READY | STATUS_DIR);
 409                 if (status == STATUS_READY) {
 410                         outb(byte,FD_DATA);
 411                         return;
 412                 }
 413         }
 414         current_track = NO_TRACK;
 415         reset = 1;
 416         printk("Unable to send byte to FDC\n\r");
 417 }
 418 
 419 static int result(void)
     /*  */
 420 {
 421         int i = 0, counter, status;
 422 
 423         if (reset)
 424                 return -1;
 425         for (counter = 0 ; counter < 10000 ; counter++) {
 426                 status = inb_p(FD_STATUS)&(STATUS_DIR|STATUS_READY|STATUS_BUSY);
 427                 if (status == STATUS_READY) {
 428                         return i;
 429                 }
 430                 if (status == (STATUS_DIR|STATUS_READY|STATUS_BUSY)) {
 431                         if (i >= MAX_REPLIES) {
 432                                 printk("floppy_stat reply overrun\n");
 433                                 break;
 434                         }
 435                         reply_buffer[i++] = inb_p(FD_DATA);
 436                 }
 437         }
 438         reset = 1;
 439         current_track = NO_TRACK;
 440         printk("Getstatus times out\n\r");
 441         return -1;
 442 }
 443 
 444 static void bad_flp_intr(void)
     /*  */
 445 {
 446         current_track = NO_TRACK;
 447         CURRENT_ERRORS++;
 448         if (CURRENT_ERRORS > MAX_ERRORS) {
 449                 floppy_deselect(current_drive);
 450                 request_done(0);
 451         }
 452         if (CURRENT_ERRORS > MAX_ERRORS/2)
 453                 reset = 1;
 454         else
 455                 recalibrate = 1;
 456 }       
 457 
 458 /*
 459  * This has only been tested for the case fdc_version == FDC_TYPE_STD.
 460  * In case you have a 82077 and want to test it, you'll have to compile
 461  * with `FDC_FIFO_UNTESTED' defined. You may also want to add support for
 462  * recognizing drives with vertical recording support.
 463  */
 464 static void configure_fdc_mode(void)
     /*  */
 465 {
 466         if (fdc_version == FDC_TYPE_82077) {
 467                 /* Enhanced version with FIFO & vertical recording. */
 468                 output_byte(FD_CONFIGURE);
 469                 output_byte(0);
 470                 output_byte(0x1A);      /* FIFO on, polling off, 10 byte treshold */
 471                 output_byte(0);         /* precompensation from track 0 upwards */
 472                 printk(DEVICE_NAME ": FIFO enabled\n");
 473         }
 474 } /* configure_fdc_mode */
 475 
 476 
 477 static void tell_sector(int nr)
     /*  */
 478 {
 479         if (nr!=7) {
 480                 printk(" -- FDC reply errror");
 481                 reset = 1;
 482         } else
 483                 printk(": track %d, head %d, sector %d", reply_buffer[3],
 484                         reply_buffer[4], reply_buffer[5]);
 485 } /* tell_sector */
 486 
 487 
 488 /*
 489  * Ok, this interrupt is called after a DMA read/write has succeeded
 490  * or failed, so we check the results, and copy any buffers.
 491  * hhb: Added better error reporting.
 492  */
 493 static void rw_interrupt(void)
     /*  */
 494 {
 495         char * buffer_area;
 496         int nr;
 497         char bad;
 498 
 499         nr = result();
 500         /* check IC to find cause of interrupt */
 501         switch ((ST0 & ST0_INTR)>>6) {
 502                 case 1: /* error occured during command execution */
 503                         bad = 1;
 504                         if (ST1 & ST1_WP) {
 505                                 printk(DEVICE_NAME ": Drive %d is write protected\n", current_drive);
 506                                 floppy_deselect(current_drive);
 507                                 request_done(0);
 508                                 bad = 0;
 509                         } else if (ST1 & ST1_OR) {
 510                                 printk(DEVICE_NAME ": Over/Underrun - retrying\n");
 511                                 /* could continue from where we stopped, but ... */
 512                                 bad = 0;
 513                         } else if (CURRENT_ERRORS > min_report_error_cnt[ST0 & ST0_DS]) {
 514                                 printk(DEVICE_NAME " %d: ", ST0 & ST0_DS);
 515                                 if (ST0 & ST0_ECE) {
 516                                         printk("Recalibrate failed!");
 517                                 } else if (ST2 & ST2_CRC) {
 518                                         printk("data CRC error");
 519                                         tell_sector(nr);
 520                                 } else if (ST1 & ST1_CRC) {
 521                                         printk("CRC error");
 522                                         tell_sector(nr);
 523                                 } else if ((ST1 & (ST1_MAM|ST1_ND)) || (ST2 & ST2_MAM)) {
 524                                         if (!probing) {
 525                                                 printk("sector not found");
 526                                                 tell_sector(nr);
 527                                         } else
 528                                                 printk("probe failed...");
 529                                 } else if (ST2 & ST2_WC) {      /* seek error */
 530                                         printk("wrong cylinder");
 531                                 } else if (ST2 & ST2_BC) {      /* cylinder marked as bad */
 532                                         printk("bad cylinder");
 533                                 } else {
 534                                         printk("unknown error. ST[0..3] are: 0x%x 0x%x 0x%x 0x%x\n", ST0, ST1, ST2, ST3);
 535                                 }
 536                                 printk("\n");
 537 
 538                         }
 539                         if (bad)
 540                                 bad_flp_intr();
 541                         redo_fd_request();
 542                         return;
 543                 case 2: /* invalid command given */
 544                         printk(DEVICE_NAME ": Invalid FDC command given!\n");
 545                         request_done(0);
 546                         return;
 547                 case 3:
 548                         printk(DEVICE_NAME ": Abnormal termination caused by polling\n");
 549                         bad_flp_intr();
 550                         redo_fd_request();
 551                         return;
 552                 default: /* (0) Normal command termination */
 553                         break;
 554         }
 555 
 556         if (probing) {
 557                 int drive = MINOR(CURRENT->dev);
 558 
 559                 if (ftd_msg[drive])
 560                         printk("Auto-detected floppy type %s in fd%d\r\n",
 561                             floppy->name,drive);
 562                 current_type[drive] = floppy;
 563                 floppy_sizes[drive] = floppy->size >> 1;
 564                 probing = 0;
 565         }
 566         if (read_track) {
 567                 buffer_track = seek_track;
 568                 buffer_drive = current_drive;
 569                 buffer_area = floppy_track_buffer +
 570                         ((sector-1 + head*floppy->sect)<<9);
 571                 copy_buffer(buffer_area,CURRENT->buffer);
 572         } else if (command == FD_READ &&
 573                 (unsigned long)(CURRENT->buffer) >= LAST_DMA_ADDR)
 574                 copy_buffer(tmp_floppy_area,CURRENT->buffer);
 575         floppy_deselect(current_drive);
 576         request_done(1);
 577         redo_fd_request();
 578 }
 579 
 580 /*
 581  * We try to read tracks, but if we get too many errors, we
 582  * go back to reading just one sector at a time.
 583  *
 584  * This means we should be able to read a sector even if there
 585  * are other bad sectors on this track.
 586  */
 587 inline void setup_rw_floppy(void)
     /*  */
 588 {
 589         setup_DMA();
 590         do_floppy = rw_interrupt;
 591         output_byte(command);
 592         if (command != FD_FORMAT) {
 593                 if (read_track) {
 594                         output_byte(current_drive);
 595                         output_byte(track);
 596                         output_byte(0);
 597                         output_byte(1);
 598                 } else {
 599                         output_byte(head<<2 | current_drive);
 600                         output_byte(track);
 601                         output_byte(head);
 602                         output_byte(sector);
 603                 }
 604                 output_byte(2);         /* sector size = 512 */
 605                 output_byte(floppy->sect);
 606                 output_byte(floppy->gap);
 607                 output_byte(0xFF);      /* sector size (0xff when n!=0 ?) */
 608         } else {
 609                 output_byte(head<<2 | current_drive);
 610                 output_byte(2);
 611                 output_byte(floppy->sect);
 612                 output_byte(floppy->fmt_gap);
 613                 output_byte(FD_FILL_BYTE);
 614         }
 615         if (reset)
 616                 redo_fd_request();
 617 }
 618 
 619 /*
 620  * This is the routine called after every seek (or recalibrate) interrupt
 621  * from the floppy controller. Note that the "unexpected interrupt" routine
 622  * also does a recalibrate, but doesn't come here.
 623  */
 624 static void seek_interrupt(void)
     /*  */
 625 {
 626 /* sense drive status */
 627         output_byte(FD_SENSEI);
 628         if (result() != 2 || (ST0 & 0xF8) != 0x20 || ST1 != seek_track) {
 629                 printk(DEVICE_NAME ": seek failed\n");
 630                 recalibrate = 1;
 631                 bad_flp_intr();
 632                 redo_fd_request();
 633                 return;
 634         }
 635         current_track = ST1;
 636         setup_rw_floppy();
 637 }
 638 
 639 /* Set perpendicular mode as required, based on data rate, if supported.
 640  * 80277: 1Mbps data rate only possible with 82077-1.
 641  * Untested!! TODO: increase MAX_BUFFER_SECTORS, add floppy_type entries.
 642  */
 643 static void inline perpendicular_mode(unsigned char rate)
     /*  */
 644 {
 645         if (fdc_version == FDC_TYPE_82077) {
 646                 output_byte(FD_PERPENDICULAR);
 647                 if (rate & 0x40) {
 648                         unsigned char r = rate & 0x03;
 649                         if (r == 0)
 650                                 output_byte(2); /* perpendicular, 500 kbps */
 651                         else if (r == 3)
 652                                 output_byte(3); /* perpendicular, 1Mbps */
 653                         else {
 654                                 printk(DEVICE_NAME ": Invalid data rate for perpendicular mode!\n");
 655                                 reset = 1;
 656                         }
 657                 } else
 658                         output_byte(0);         /* conventional mode */
 659         } else {
 660                 if (rate & 0x40) {
 661                         printk(DEVICE_NAME ": perpendicular mode not supported by FDC.\n");
 662                         reset = 1;
 663                 }
 664         }
 665 } /* perpendicular_mode */
 666 
 667 /*
 668  * This routine is called when everything should be correctly set up
 669  * for the transfer (ie floppy motor is on and the correct floppy is
 670  * selected).
 671  */
 672 static void transfer(void)
     /*  */
 673 {
 674         read_track = (command == FD_READ) && (CURRENT_ERRORS < 4) &&
 675             (floppy->sect <= MAX_BUFFER_SECTORS);
 676         if (cur_spec1 != floppy->spec1) {
 677                 cur_spec1 = floppy->spec1;
 678                 output_byte(FD_SPECIFY);
 679                 output_byte(cur_spec1);         /* hut etc */
 680                 output_byte(6);                 /* Head load time =6ms, DMA */
 681         }
 682         if (cur_rate != floppy->rate) {
 683                 /* use bit 6 of floppy->rate to indicate perpendicular mode */
 684                 perpendicular_mode(floppy->rate);
 685                 outb_p(cur_rate = ((floppy->rate)) & ~0x40, FD_DCR);
 686         }
 687         if (reset) {
 688                 redo_fd_request();
 689                 return;
 690         }
 691         if (!seek) {
 692                 setup_rw_floppy();
 693                 return;
 694         }
 695         do_floppy = seek_interrupt;
 696         output_byte(FD_SEEK);
 697         if (read_track)
 698                 output_byte(current_drive);
 699         else
 700                 output_byte((head<<2) | current_drive);
 701         output_byte(seek_track);
 702         if (reset)
 703                 redo_fd_request();
 704 }
 705 
 706 /*
 707  * Special case - used after a unexpected interrupt (or reset)
 708  */
 709 
 710 static void recalibrate_floppy(void);
 711 
 712 static void recal_interrupt(void)
     /*  */
 713 {
 714         output_byte(FD_SENSEI);
 715         current_track = NO_TRACK;
 716         if (result()!=2 || (ST0 & 0xE0) == 0x60)
 717                 reset = 1;
 718 /* Recalibrate until track 0 is reached. Might help on some errors. */
 719         if ((ST0 & 0x10) == 0x10) recalibrate_floppy();
 720         else redo_fd_request();
 721 }
 722 
 723 static void unexpected_floppy_interrupt(void)
     /*  */
 724 {
 725         current_track = NO_TRACK;
 726         output_byte(FD_SENSEI);
 727         printk(DEVICE_NAME ": unexpected interrupt\n");
 728         if (result()!=2 || (ST0 & 0xE0) == 0x60)
 729                 reset = 1;
 730         else
 731                 recalibrate = 1;
 732 }
 733 
 734 static void recalibrate_floppy(void)
     /*  */
 735 {
 736         recalibrate = 0;
 737         current_track = 0;
 738         do_floppy = recal_interrupt;
 739         output_byte(FD_RECALIBRATE);
 740         output_byte(head<<2 | current_drive);
 741         if (reset)
 742                 redo_fd_request();
 743 }
 744 
 745 /*
 746  * Must do 4 FD_SENSEIs after reset because of ``drive polling''.
 747  */
 748 static void reset_interrupt(void)
     /*  */
 749 {
 750         short i;
 751 
 752         for (i=0; i<4; i++) {
 753                 output_byte(FD_SENSEI);
 754                 (void) result();
 755         }
 756         output_byte(FD_SPECIFY);
 757         output_byte(cur_spec1);         /* hut etc */
 758         output_byte(6);                 /* Head load time =6ms, DMA */
 759         configure_fdc_mode();           /* reprogram if smart fdc */
 760         if (!recover) redo_fd_request();
 761         else {
 762                 recalibrate_floppy();
 763                 recover = 0;
 764         }
 765 }
 766 
 767 /*
 768  * reset is done by pulling bit 2 of DOR low for a while.
 769  */
 770 static void reset_floppy(void)
     /*  */
 771 {
 772         int i;
 773 
 774         do_floppy = reset_interrupt;
 775         reset = 0;
 776         current_track = NO_TRACK;
 777         cur_spec1 = -1;
 778         cur_rate = -1;
 779         recalibrate = 1;
 780         printk("Reset-floppy called\n\r");
 781         cli();
 782         outb_p(current_DOR & ~0x04,FD_DOR);
 783         for (i=0 ; i<1000 ; i++)
 784                 __asm__("nop");
 785         outb(current_DOR,FD_DOR);
 786         sti();
 787 }
 788 
 789 static void floppy_shutdown(void)
     /*  */
 790 {
 791         cli();
 792         request_done(0);
 793         recover = 1;
 794         reset_floppy();
 795         sti();
 796 }
 797 
 798 static void shake_done(void)
     /*  */
 799 {
 800         current_track = NO_TRACK;
 801         if (inb(FD_DIR) & 0x80) request_done(0);
 802         redo_fd_request();
 803 }
 804 
 805 static int retry_recal(void (*proc)(void))
     /*  */
 806 {
 807         output_byte(FD_SENSEI);
 808         if (result() == 2 && (ST0 & 0x10) != 0x10) return 0;
 809         do_floppy = proc;
 810         output_byte(FD_RECALIBRATE);
 811         output_byte(head<<2 | current_drive);
 812         return 1;
 813 }
 814 
 815 static void shake_zero(void)
     /*  */
 816 {
 817         if (!retry_recal(shake_zero)) shake_done();
 818 }
 819 
 820 static void shake_one(void)
     /*  */
 821 {
 822         if (retry_recal(shake_one)) return;
 823         do_floppy = shake_done;
 824         output_byte(FD_SEEK);
 825         output_byte(head << 2 | current_drive);
 826         output_byte(1);
 827 }
 828 
 829 static void floppy_on_interrupt(void)
     /*  */
 830 {
 831         if (inb(FD_DIR) & 0x80) {
 832                 changed_floppies |= 1<<current_drive;
 833                 buffer_track = -1;
 834                 if (keep_data[current_drive]) {
 835                         if (keep_data[current_drive] > 0)
 836                                 keep_data[current_drive]--;
 837                 }
 838                 else {
 839                         if (ftd_msg[current_drive] && current_type[
 840                             current_drive] != NULL)
 841                                 printk("Disk type is undefined after disk "
 842                                     "change in fd%d\r\n",current_drive);
 843                         current_type[current_drive] = NULL;
 844                         floppy_sizes[current_drive] = MAX_DISK_SIZE;
 845                 }
 846 /* Forcing the drive to seek makes the "media changed" condition go away.
 847  * There should be a cleaner solution for that ...
 848  */
 849                 if (!reset && !recalibrate) {
 850                         do_floppy = (current_track && current_track != NO_TRACK)
 851                             ?  shake_zero : shake_one;
 852                         output_byte(FD_RECALIBRATE);
 853                         output_byte(head<<2 | current_drive);
 854                         return;
 855                 }
 856         }
 857         if (reset) {
 858                 reset_floppy();
 859                 return;
 860         }
 861         if (recalibrate) {
 862                 recalibrate_floppy();
 863                 return;
 864         }
 865 /* We cannot do a floppy-select, as that might sleep. We just force it */
 866         selected = 1;
 867         if (current_drive != (current_DOR & 3)) {
 868                 seek = 1;
 869                 current_track = NO_TRACK;
 870                 current_DOR &= 0xFC;
 871                 current_DOR |= current_drive;
 872                 outb(current_DOR,FD_DOR);
 873                 add_timer(2,&transfer);
 874         } else
 875                 transfer();
 876 }
 877 
 878 static void setup_format_params(void)
     /*  */
 879 {
 880     unsigned char *here = (unsigned char *) tmp_floppy_area;
 881     int count;
 882 
 883     /* XXX: should do a check to see this fits in tmp_floppy_area!! */
 884     for (count = 1; count <= floppy->sect; count++) {
 885         *here++ = track;
 886         *here++ = head;
 887         *here++ = count;
 888         *here++ = 2; /* 512 bytes */
 889     }
 890 }
 891 
 892 static void redo_fd_request(void)
     /*  */
 893 {
 894         unsigned int block;
 895         char * buffer_area;
 896         int device;
 897 
 898 repeat:
 899         if (format_status == FORMAT_WAIT)
 900                 format_status = FORMAT_BUSY;
 901         if (format_status != FORMAT_BUSY) {
 902                 if (!CURRENT) {
 903                         if (!fdc_busy)
 904                                 printk("FDC access conflict");
 905                         fdc_busy = 0;
 906                         wake_up(&fdc_wait);
 907                         CLEAR_INTR;
 908                         return;
 909                 }
 910                 if (MAJOR(CURRENT->dev) != MAJOR_NR)
 911                         panic(DEVICE_NAME ": request list destroyed"); \
 912                 if (CURRENT->bh) {
 913                         if (!CURRENT->bh->b_lock)
 914                                 panic(DEVICE_NAME ": block not locked");
 915                 }
 916         }
 917         seek = 0;
 918         probing = 0;
 919         device = MINOR(CURRENT_DEVICE);
 920         if (device > 3)
 921                 floppy = (device >> 2) + floppy_type;
 922         else { /* Auto-detection */
 923                 if ((floppy = current_type[device & 3]) == NULL) {
 924                         probing = 1;
 925                         if ((floppy = base_type[device & 3]) ==
 926                             NULL) {
 927                                 request_done(0);
 928                                 goto repeat;
 929                         }
 930                         floppy += CURRENT_ERRORS & 1;
 931                 }
 932         }
 933         if (format_status != FORMAT_BUSY) {
 934                 if (current_drive != CURRENT_DEV) {
 935                         current_track = NO_TRACK;
 936                         current_drive = CURRENT_DEV;
 937                 }
 938                 block = CURRENT->sector;
 939                 if (block+2 > floppy->size) {
 940                         request_done(0);
 941                         goto repeat;
 942                 }
 943                 sector = block % floppy->sect;
 944                 block /= floppy->sect;
 945                 head = block % floppy->head;
 946                 track = block / floppy->head;
 947                 seek_track = track << floppy->stretch;
 948                 if (CURRENT->cmd == READ)
 949                         command = FD_READ;
 950                 else if (CURRENT->cmd == WRITE)
 951                         command = FD_WRITE;
 952                 else {
 953                         printk("do_fd_request: unknown command\n");
 954                         request_done(0);
 955                         goto repeat;
 956                 }
 957         } else {
 958                 if (current_drive != (format_req.device & 3))
 959                         current_track = NO_TRACK;
 960                 current_drive = format_req.device & 3;
 961                 if (((unsigned) format_req.track) >= floppy->track ||
 962                     (format_req.head & 0xfffe) || probing) {
 963                         request_done(0);
 964                         goto repeat;
 965                 }
 966                 head = format_req.head;
 967                 track = format_req.track;
 968                 seek_track = track << floppy->stretch;
 969                 if (seek_track == buffer_track) buffer_track = -1;
 970                 command = FD_FORMAT;
 971                 setup_format_params();
 972         }
 973         timer_table[FLOPPY_TIMER].expires = jiffies+10*HZ;
 974         timer_active |= 1 << FLOPPY_TIMER;
 975         if ((seek_track == buffer_track) &&
 976          (current_drive == buffer_drive)) {
 977                 buffer_area = floppy_track_buffer +
 978                         ((sector + head*floppy->sect)<<9);
 979                 if (command == FD_READ) {
 980                         copy_buffer(buffer_area,CURRENT->buffer);
 981                         request_done(1);
 982                         goto repeat;
 983                 } else if (command == FD_WRITE)
 984                         copy_buffer(CURRENT->buffer,buffer_area);
 985         }
 986         if (seek_track != current_track)
 987                 seek = 1;
 988         sector++;
 989         add_timer(ticks_to_floppy_on(current_drive),&floppy_on_interrupt);
 990 }
 991 
 992 void do_fd_request(void)
     /*  */
 993 {
 994         cli();
 995         while (fdc_busy) sleep_on(&fdc_wait);
 996         fdc_busy = 1;
 997         sti();
 998         redo_fd_request();
 999 }
1000 
1001 static int fd_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
     /*  */
1002     unsigned int param)
1003 {
1004         int drive,cnt,okay;
1005         struct floppy_struct *this;
1006 
1007         switch (cmd) {
1008                 RO_IOCTLS(inode->i_rdev,param);
1009         }
1010         drive = MINOR(inode->i_rdev);
1011         switch (cmd) {
1012                 case FDFMTBEG:
1013                         if (!suser())
1014                                 return -EPERM;
1015                         return 0;
1016                 case FDFMTEND:
1017                         if (!suser())
1018                                 return -EPERM;
1019                         cli();
1020                         fake_change |= 1 << (drive & 3);
1021                         sti();
1022                         drive &= 3;
1023                         cmd = FDCLRPRM;
1024                         break;
1025                 case FDGETPRM:
1026                         if (drive > 3) this = &floppy_type[drive >> 2];
1027                         else if ((this = current_type[drive & 3]) == NULL)
1028                                     return -ENODEV;
1029                         verify_area((void *) param,sizeof(struct floppy_struct));
1030                         for (cnt = 0; cnt < sizeof(struct floppy_struct); cnt++)
1031                                 put_fs_byte(((char *) this)[cnt],
1032                                     (char *) param+cnt);
1033                         return 0;
1034                 case FDFMTTRK:
1035                         if (!suser())
1036                                 return -EPERM;
1037                         cli();
1038                         while (format_status != FORMAT_NONE)
1039                                 sleep_on(&format_done);
1040                         for (cnt = 0; cnt < sizeof(struct format_descr); cnt++)
1041                                 ((char *) &format_req)[cnt] = get_fs_byte(
1042                                     (char *) param+cnt);
1043                         format_req.device = drive;
1044                         format_status = FORMAT_WAIT;
1045                         format_errors = 0;
1046                         while (format_status != FORMAT_OKAY && format_status !=
1047                             FORMAT_ERROR) {
1048                                 if (fdc_busy) sleep_on(&fdc_wait);
1049                                 else {
1050                                         fdc_busy = 1;
1051                                         redo_fd_request();
1052                                 }
1053                         }
1054                         while (format_status != FORMAT_OKAY && format_status !=
1055                             FORMAT_ERROR)
1056                                 sleep_on(&format_done);
1057                         sti();
1058                         okay = format_status == FORMAT_OKAY;
1059                         format_status = FORMAT_NONE;
1060                         wake_up(&format_done);
1061                         return okay ? 0 : -EIO;
1062         }
1063         if (!suser())
1064                 return -EPERM;
1065         if (drive < 0 || drive > 3)
1066                 return -EINVAL;
1067         switch (cmd) {
1068                 case FDCLRPRM:
1069                         current_type[drive] = NULL;
1070                         floppy_sizes[drive] = MAX_DISK_SIZE;
1071                         keep_data[drive] = 0;
1072                         break;
1073                 case FDSETPRM:
1074                 case FDDEFPRM:
1075                         for (cnt = 0; cnt < sizeof(struct floppy_struct); cnt++)
1076                                 ((char *) &user_params[drive])[cnt] =
1077                                     get_fs_byte((char *) param+cnt);
1078                         current_type[drive] = &user_params[drive];
1079                         floppy_sizes[drive] = user_params[drive].size >> 1;
1080                         if (cmd == FDDEFPRM) keep_data[drive] = -1;
1081                         else {
1082                                 cli();
1083                                 while (fdc_busy) sleep_on(&fdc_wait);
1084                                 fdc_busy = 1;
1085                                 sti();
1086                                 outb_p((current_DOR & 0xfc) | drive |
1087                                     (0x10 << drive),FD_DOR);
1088                                 for (cnt = 0; cnt < 1000; cnt++) __asm__("nop");
1089                                 keep_data[drive] = (inb(FD_DIR) & 0x80) ? 1 : 0;
1090                                 outb_p(current_DOR,FD_DOR);
1091                                 fdc_busy = 0;
1092                                 wake_up(&fdc_wait);
1093                         }
1094                         break;
1095                 case FDMSGON:
1096                         ftd_msg[drive] = 1;
1097                         break;
1098                 case FDMSGOFF:
1099                         ftd_msg[drive] = 0;
1100                         break;
1101                 case FDSETEMSGTRESH:
1102                         min_report_error_cnt[drive] = (unsigned short) (param & 0x0f);
1103                         break;
1104                 default:
1105                         return -EINVAL;
1106         }
1107         return 0;
1108 }
1109 
1110 #define CMOS_READ(addr) ({ \
1111 outb_p(0x80|addr,0x70); \
1112 inb_p(0x71); \
1113 })
1114 
1115 static struct floppy_struct *find_base(int drive,int code)
     /*  */
1116 {
1117         struct floppy_struct *base;
1118 
1119         if (code > 0 && code < 5) {
1120                 base = &floppy_types[(code-1)*2];
1121                 printk("fd%d is %s",drive,base->name);
1122                 return base;
1123         }
1124         printk("fd%d is unknown type %d",drive,code);
1125         return NULL;
1126 }
1127 
1128 static void config_types(void)
     /*  */
1129 {
1130         printk("Floppy drive(s): ");
1131         base_type[0] = find_base(0,(CMOS_READ(0x10) >> 4) & 15);
1132         if (((CMOS_READ(0x14) >> 6) & 1) == 0)
1133                 base_type[1] = NULL;
1134         else {
1135                 printk(", ");
1136                 base_type[1] = find_base(1,CMOS_READ(0x10) & 15);
1137         }
1138         base_type[2] = base_type[3] = NULL;
1139         printk("\r\n");
1140 }
1141 
1142 /*
1143  * floppy_open check for aliasing (/dev/fd0 can be the same as
1144  * /dev/PS0 etc), and disallows simultaneous access to the same
1145  * drive with different device numbers.
1146  */
1147 static int floppy_open(struct inode * inode, struct file * filp)
     /*  */
1148 {
1149         int drive;
1150         int old_dev;
1151 
1152         drive = inode->i_rdev & 3;
1153         old_dev = fd_device[drive];
1154         if (fd_ref[drive])
1155                 if (old_dev != inode->i_rdev)
1156                         return -EBUSY;
1157         fd_ref[drive]++;
1158         fd_device[drive] = inode->i_rdev;
1159         if (old_dev && old_dev != inode->i_rdev)
1160                 invalidate_buffers(old_dev);
1161         if (filp && filp->f_mode)
1162                 check_disk_change(inode->i_rdev);
1163         return 0;
1164 }
1165 
1166 static void floppy_release(struct inode * inode, struct file * filp)
     /*  */
1167 {
1168         sync_dev(inode->i_rdev);
1169         if (!fd_ref[inode->i_rdev & 3]--) {
1170                 printk("floppy_release with fd_ref == 0");
1171                 fd_ref[inode->i_rdev & 3] = 0;
1172         }
1173 }
1174 
1175 static struct file_operations floppy_fops = {
1176         NULL,                   /* lseek - default */
1177         block_read,             /* read - general block-dev read */
1178         block_write,            /* write - general block-dev write */
1179         NULL,                   /* readdir - bad */
1180         NULL,                   /* select */
1181         fd_ioctl,               /* ioctl */
1182         floppy_open,            /* open */
1183         floppy_release          /* release */
1184 };
1185 
1186 
1187 /*
1188  * The version command is not supposed to generate an interrupt, but
1189  * my FDC does, except when booting in SVGA screen mode.
1190  * When it does generate an interrupt, it doesn't return any status bytes.
1191  * It appears to have something to do with the version command...
1192  */
1193 static void ignore_interrupt(void)
     /*  */
1194 {
1195         if (result() != 0) {
1196                 printk(DEVICE_NAME ": weird interrupt ignored\n");
1197                 reset = 1;
1198         }
1199         CLEAR_INTR;     /* ignore only once */
1200 }
1201 
1202 
1203 static void floppy_interrupt(int unused)
     /*  */
1204 {
1205         void (*handler)(void) = DEVICE_INTR;
1206 
1207         DEVICE_INTR = NULL;
1208         if (!handler)
1209                 handler = unexpected_floppy_interrupt;
1210         handler();
1211 }
1212 
1213 /*
1214  * This is the floppy IRQ description. The SA_INTERRUPT in sa_flags
1215  * means we run the IRQ-handler with interrupts disabled.
1216  */
1217 static struct sigaction floppy_sigaction = {
1218         floppy_interrupt,
1219         0,
1220         SA_INTERRUPT,
1221         NULL
1222 };
1223 
1224 void floppy_init(void)
     /*  */
1225 {
1226         outb(current_DOR,FD_DOR);
1227         blk_size[MAJOR_NR] = floppy_sizes;
1228         blk_dev[MAJOR_NR].request_fn = DEVICE_REQUEST;
1229         blkdev_fops[MAJOR_NR] = &floppy_fops;
1230         timer_table[FLOPPY_TIMER].fn = floppy_shutdown;
1231         timer_active &= ~(1 << FLOPPY_TIMER);
1232         config_types();
1233         if (irqaction(FLOPPY_IRQ,&floppy_sigaction))
1234                 printk("Unable to grab IRQ%d for the floppy driver\n",FLOPPY_IRQ);
1235 
1236         /* Try to determine the floppy controller type */
1237         DEVICE_INTR = ignore_interrupt; /* don't ask ... */
1238         output_byte(FD_VERSION);        /* get FDC version code */
1239         if (result() != 1) {
1240                 printk(DEVICE_NAME ": FDC failed to return version byte\n");
1241                 fdc_version = FDC_TYPE_STD;
1242         } else
1243                 fdc_version = reply_buffer[0];
1244         if (fdc_version != FDC_TYPE_STD) 
1245                 printk(DEVICE_NAME ": FDC version 0x%x\n", fdc_version);
1246 #ifndef FDC_FIFO_UNTESTED
1247         fdc_version = FDC_TYPE_STD;     /* force std fdc type; can't test other. */
1248 #endif
1249         configure_fdc_mode();
1250 }
/* */
root/kernel/blk_drv/floppy.c

DEFINITIONS
