1 /*
2 * linux/amiga/amiflop.c
3 *
4 * Copyright (C) 1993 Greg Harp
5 * Portions of this driver are based on code contributed by Brad Pepers
6 *
7 * revised 28.5.95 by Joerg Dorchain
8 * - now no bugs(?) any more for both HD & DD
9 * - added support for 40 Track 5.25" drives, 80-track hopefully behaves
10 * like 3.5" dd (no way to test - are there any 5.25" drives out there
11 * that work on an A4000?)
12 * - wrote formatting routine (maybe dirty, but works)
13 *
14 * june/july 1995 added ms-dos support by Joerg Dorchain
15 * (portions based on messydos.device and various contributors)
16 * - currently only 9 and 18 sector disks
17 *
18 * - fixed a bug with the internal trackbuffer when using multiple
19 * disks the same time
20 * - made formatting a bit safer
21 * - added command line and machine based default for "silent" df0
22 *
23 * december 1995 adapted for 1.2.13pl4 by Joerg Dorchain
24 * - works but I think it's inefficient. (look in redo_fd_request)
25 * But the changes were very efficient. (only three and a half lines)
26 *
27 * january 1996 added special ioctl for tracking down read/write problems
28 * - usage ioctl(d, RAW_TRACK, ptr); the raw track buffer (MFM-encoded data
29 * is copied to area. (area should be large enough since no checking is
30 * done - 30K is currently sufficient). return the actual size of the
31 * trackbuffer
32 * - replaced udelays() by a timer (CIAA timer B) for the waits
33 * needed for the disk mechanic.
34 *
35 * february 1996 fixed error recovery and multiple disk access
36 * - both got broken the first time I tampered with the driver :-(
37 * - still not safe, but better than before
38 *
39 * revised Marts 3rd, 1996 by Jes Sorensen for use in the 1.3.28 kernel.
40 * - Minor changes to accept the kdev_t.
41 * - Replaced some more udelays with ms_delays. Udelay is just a loop,
42 * and so the delay will be different depending on the given
43 * processor :-(
44 * - The driver could use a major cleanup because of the new
45 * major/minor handling that came with kdev_t. It seems to work for
46 * the time being, but I can't guarantee that it will stay like
47 * that when we start using 16 (24?) bit minors.
48 *
49 * restructured jan 1997 by Joerg Dorchain
50 * - Fixed Bug accessing multiple disks
51 * - some code cleanup
52 * - added trackbuffer for each drive to speed things up
53 * - fixed some race conditions (who finds the next may send it to me ;-)
54 */
55
56 #include <linux/module.h>
57 #include <linux/slab.h>
58
59 #include <linux/fd.h>
60 #include <linux/hdreg.h>
61 #include <linux/delay.h>
62 #include <linux/init.h>
63 #include <linux/mutex.h>
64 #include <linux/amifdreg.h>
65 #include <linux/amifd.h>
66 #include <linux/fs.h>
67 #include <linux/blkdev.h>
68 #include <linux/elevator.h>
69 #include <linux/interrupt.h>
70 #include <linux/platform_device.h>
71
72 #include <asm/setup.h>
73 #include <asm/uaccess.h>
74 #include <asm/amigahw.h>
75 #include <asm/amigaints.h>
76 #include <asm/irq.h>
77
78 #undef DEBUG /* print _LOTS_ of infos */
79
80 #define RAW_IOCTL
81 #ifdef RAW_IOCTL
82 #define IOCTL_RAW_TRACK 0x5254524B /* 'RTRK' */
83 #endif
84
85 /*
86 * Defines
87 */
88
89 /*
90 * Error codes
91 */
92 #define FD_OK 0 /* operation succeeded */
93 #define FD_ERROR -1 /* general error (seek, read, write, etc) */
94 #define FD_NOUNIT 1 /* unit does not exist */
95 #define FD_UNITBUSY 2 /* unit already active */
96 #define FD_NOTACTIVE 3 /* unit is not active */
97 #define FD_NOTREADY 4 /* unit is not ready (motor not on/no disk) */
98
99 #define MFM_NOSYNC 1
100 #define MFM_HEADER 2
101 #define MFM_DATA 3
102 #define MFM_TRACK 4
103
104 /*
105 * Floppy ID values
106 */
107 #define FD_NODRIVE 0x00000000 /* response when no unit is present */
108 #define FD_DD_3 0xffffffff /* double-density 3.5" (880K) drive */
109 #define FD_HD_3 0x55555555 /* high-density 3.5" (1760K) drive */
110 #define FD_DD_5 0xaaaaaaaa /* double-density 5.25" (440K) drive */
111
112 static DEFINE_MUTEX(amiflop_mutex);
113 static unsigned long int fd_def_df0 = FD_DD_3; /* default for df0 if it doesn't identify */
114
115 module_param(fd_def_df0, ulong, 0);
116 MODULE_LICENSE("GPL");
117
118 /*
119 * Macros
120 */
121 #define MOTOR_ON (ciab.prb &= ~DSKMOTOR)
122 #define MOTOR_OFF (ciab.prb |= DSKMOTOR)
123 #define SELECT(mask) (ciab.prb &= ~mask)
124 #define DESELECT(mask) (ciab.prb |= mask)
125 #define SELMASK(drive) (1 << (3 + (drive & 3)))
126
127 static struct fd_drive_type drive_types[] = {
128 /* code name tr he rdsz wrsz sm pc1 pc2 sd st st*/
129 /* warning: times are now in milliseconds (ms) */
130 { FD_DD_3, "DD 3.5", 80, 2, 14716, 13630, 1, 80,161, 3, 18, 1},
131 { FD_HD_3, "HD 3.5", 80, 2, 28344, 27258, 2, 80,161, 3, 18, 1},
132 { FD_DD_5, "DD 5.25", 40, 2, 14716, 13630, 1, 40, 81, 6, 30, 2},
133 { FD_NODRIVE, "No Drive", 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
134 };
135 static int num_dr_types = ARRAY_SIZE(drive_types);
136
137 static int amiga_read(int), dos_read(int);
138 static void amiga_write(int), dos_write(int);
139 static struct fd_data_type data_types[] = {
140 { "Amiga", 11 , amiga_read, amiga_write},
141 { "MS-Dos", 9, dos_read, dos_write}
142 };
143
144 /* current info on each unit */
145 static struct amiga_floppy_struct unit[FD_MAX_UNITS];
146
147 static struct timer_list flush_track_timer[FD_MAX_UNITS];
148 static struct timer_list post_write_timer;
149 static struct timer_list motor_on_timer;
150 static struct timer_list motor_off_timer[FD_MAX_UNITS];
151 static int on_attempts;
152
153 /* Synchronization of FDC access */
154 /* request loop (trackbuffer) */
155 static volatile int fdc_busy = -1;
156 static volatile int fdc_nested;
157 static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
158
159 static DECLARE_COMPLETION(motor_on_completion);
160
161 static volatile int selected = -1; /* currently selected drive */
162
163 static int writepending;
164 static int writefromint;
165 static char *raw_buf;
166 static int fdc_queue;
167
168 static DEFINE_SPINLOCK(amiflop_lock);
169
170 #define RAW_BUF_SIZE 30000 /* size of raw disk data */
171
172 /*
173 * These are global variables, as that's the easiest way to give
174 * information to interrupts. They are the data used for the current
175 * request.
176 */
177 static volatile char block_flag;
178 static DECLARE_WAIT_QUEUE_HEAD(wait_fd_block);
179
180 /* MS-Dos MFM Coding tables (should go quick and easy) */
181 static unsigned char mfmencode[16]={
182 0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15,
183 0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55
184 };
185 static unsigned char mfmdecode[128];
186
187 /* floppy internal millisecond timer stuff */
188 static DECLARE_COMPLETION(ms_wait_completion);
189 #define MS_TICKS ((amiga_eclock+50)/1000)
190
191 /*
192 * Note that MAX_ERRORS=X doesn't imply that we retry every bad read
193 * max X times - some types of errors increase the errorcount by 2 or
194 * even 3, so we might actually retry only X/2 times before giving up.
195 */
196 #define MAX_ERRORS 12
197
198 #define custom amiga_custom
199
200 /* Prevent "aliased" accesses. */
201 static int fd_ref[4] = { 0,0,0,0 };
202 static int fd_device[4] = { 0, 0, 0, 0 };
203
204 /*
205 * Here come the actual hardware access and helper functions.
206 * They are not reentrant and single threaded because all drives
207 * share the same hardware and the same trackbuffer.
208 */
209
210 /* Milliseconds timer */
211
ms_isr(int irq,void * dummy)212 static irqreturn_t ms_isr(int irq, void *dummy)
213 {
214 complete(&ms_wait_completion);
215 return IRQ_HANDLED;
216 }
217
218 /* all waits are queued up
219 A more generic routine would do a schedule a la timer.device */
ms_delay(int ms)220 static void ms_delay(int ms)
221 {
222 int ticks;
223 static DEFINE_MUTEX(mutex);
224
225 if (ms > 0) {
226 mutex_lock(&mutex);
227 ticks = MS_TICKS*ms-1;
228 ciaa.tblo=ticks%256;
229 ciaa.tbhi=ticks/256;
230 ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */
231 wait_for_completion(&ms_wait_completion);
232 mutex_unlock(&mutex);
233 }
234 }
235
236 /* Hardware semaphore */
237
238 /* returns true when we would get the semaphore */
try_fdc(int drive)239 static inline int try_fdc(int drive)
240 {
241 drive &= 3;
242 return ((fdc_busy < 0) || (fdc_busy == drive));
243 }
244
get_fdc(int drive)245 static void get_fdc(int drive)
246 {
247 unsigned long flags;
248
249 drive &= 3;
250 #ifdef DEBUG
251 printk("get_fdc: drive %d fdc_busy %d fdc_nested %d\n",drive,fdc_busy,fdc_nested);
252 #endif
253 local_irq_save(flags);
254 wait_event(fdc_wait, try_fdc(drive));
255 fdc_busy = drive;
256 fdc_nested++;
257 local_irq_restore(flags);
258 }
259
rel_fdc(void)260 static inline void rel_fdc(void)
261 {
262 #ifdef DEBUG
263 if (fdc_nested == 0)
264 printk("fd: unmatched rel_fdc\n");
265 printk("rel_fdc: fdc_busy %d fdc_nested %d\n",fdc_busy,fdc_nested);
266 #endif
267 fdc_nested--;
268 if (fdc_nested == 0) {
269 fdc_busy = -1;
270 wake_up(&fdc_wait);
271 }
272 }
273
fd_select(int drive)274 static void fd_select (int drive)
275 {
276 unsigned char prb = ~0;
277
278 drive&=3;
279 #ifdef DEBUG
280 printk("selecting %d\n",drive);
281 #endif
282 if (drive == selected)
283 return;
284 get_fdc(drive);
285 selected = drive;
286
287 if (unit[drive].track % 2 != 0)
288 prb &= ~DSKSIDE;
289 if (unit[drive].motor == 1)
290 prb &= ~DSKMOTOR;
291 ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
292 ciab.prb = prb;
293 prb &= ~SELMASK(drive);
294 ciab.prb = prb;
295 rel_fdc();
296 }
297
fd_deselect(int drive)298 static void fd_deselect (int drive)
299 {
300 unsigned char prb;
301 unsigned long flags;
302
303 drive&=3;
304 #ifdef DEBUG
305 printk("deselecting %d\n",drive);
306 #endif
307 if (drive != selected) {
308 printk(KERN_WARNING "Deselecting drive %d while %d was selected!\n",drive,selected);
309 return;
310 }
311
312 get_fdc(drive);
313 local_irq_save(flags);
314
315 selected = -1;
316
317 prb = ciab.prb;
318 prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
319 ciab.prb = prb;
320
321 local_irq_restore (flags);
322 rel_fdc();
323
324 }
325
motor_on_callback(unsigned long nr)326 static void motor_on_callback(unsigned long nr)
327 {
328 if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {
329 complete_all(&motor_on_completion);
330 } else {
331 motor_on_timer.expires = jiffies + HZ/10;
332 add_timer(&motor_on_timer);
333 }
334 }
335
fd_motor_on(int nr)336 static int fd_motor_on(int nr)
337 {
338 nr &= 3;
339
340 del_timer(motor_off_timer + nr);
341
342 if (!unit[nr].motor) {
343 unit[nr].motor = 1;
344 fd_select(nr);
345
346 reinit_completion(&motor_on_completion);
347 motor_on_timer.data = nr;
348 mod_timer(&motor_on_timer, jiffies + HZ/2);
349
350 on_attempts = 10;
351 wait_for_completion(&motor_on_completion);
352 fd_deselect(nr);
353 }
354
355 if (on_attempts == 0) {
356 on_attempts = -1;
357 #if 0
358 printk (KERN_ERR "motor_on failed, turning motor off\n");
359 fd_motor_off (nr);
360 return 0;
361 #else
362 printk (KERN_WARNING "DSKRDY not set after 1.5 seconds - assuming drive is spinning notwithstanding\n");
363 #endif
364 }
365
366 return 1;
367 }
368
fd_motor_off(unsigned long drive)369 static void fd_motor_off(unsigned long drive)
370 {
371 long calledfromint;
372 #ifdef MODULE
373 long decusecount;
374
375 decusecount = drive & 0x40000000;
376 #endif
377 calledfromint = drive & 0x80000000;
378 drive&=3;
379 if (calledfromint && !try_fdc(drive)) {
380 /* We would be blocked in an interrupt, so try again later */
381 motor_off_timer[drive].expires = jiffies + 1;
382 add_timer(motor_off_timer + drive);
383 return;
384 }
385 unit[drive].motor = 0;
386 fd_select(drive);
387 udelay (1);
388 fd_deselect(drive);
389 }
390
floppy_off(unsigned int nr)391 static void floppy_off (unsigned int nr)
392 {
393 int drive;
394
395 drive = nr & 3;
396 /* called this way it is always from interrupt */
397 motor_off_timer[drive].data = nr | 0x80000000;
398 mod_timer(motor_off_timer + drive, jiffies + 3*HZ);
399 }
400
fd_calibrate(int drive)401 static int fd_calibrate(int drive)
402 {
403 unsigned char prb;
404 int n;
405
406 drive &= 3;
407 get_fdc(drive);
408 if (!fd_motor_on (drive))
409 return 0;
410 fd_select (drive);
411 prb = ciab.prb;
412 prb |= DSKSIDE;
413 prb &= ~DSKDIREC;
414 ciab.prb = prb;
415 for (n = unit[drive].type->tracks/2; n != 0; --n) {
416 if (ciaa.pra & DSKTRACK0)
417 break;
418 prb &= ~DSKSTEP;
419 ciab.prb = prb;
420 prb |= DSKSTEP;
421 udelay (2);
422 ciab.prb = prb;
423 ms_delay(unit[drive].type->step_delay);
424 }
425 ms_delay (unit[drive].type->settle_time);
426 prb |= DSKDIREC;
427 n = unit[drive].type->tracks + 20;
428 for (;;) {
429 prb &= ~DSKSTEP;
430 ciab.prb = prb;
431 prb |= DSKSTEP;
432 udelay (2);
433 ciab.prb = prb;
434 ms_delay(unit[drive].type->step_delay + 1);
435 if ((ciaa.pra & DSKTRACK0) == 0)
436 break;
437 if (--n == 0) {
438 printk (KERN_ERR "fd%d: calibrate failed, turning motor off\n", drive);
439 fd_motor_off (drive);
440 unit[drive].track = -1;
441 rel_fdc();
442 return 0;
443 }
444 }
445 unit[drive].track = 0;
446 ms_delay(unit[drive].type->settle_time);
447
448 rel_fdc();
449 fd_deselect(drive);
450 return 1;
451 }
452
fd_seek(int drive,int track)453 static int fd_seek(int drive, int track)
454 {
455 unsigned char prb;
456 int cnt;
457
458 #ifdef DEBUG
459 printk("seeking drive %d to track %d\n",drive,track);
460 #endif
461 drive &= 3;
462 get_fdc(drive);
463 if (unit[drive].track == track) {
464 rel_fdc();
465 return 1;
466 }
467 if (!fd_motor_on(drive)) {
468 rel_fdc();
469 return 0;
470 }
471 if (unit[drive].track < 0 && !fd_calibrate(drive)) {
472 rel_fdc();
473 return 0;
474 }
475
476 fd_select (drive);
477 cnt = unit[drive].track/2 - track/2;
478 prb = ciab.prb;
479 prb |= DSKSIDE | DSKDIREC;
480 if (track % 2 != 0)
481 prb &= ~DSKSIDE;
482 if (cnt < 0) {
483 cnt = - cnt;
484 prb &= ~DSKDIREC;
485 }
486 ciab.prb = prb;
487 if (track % 2 != unit[drive].track % 2)
488 ms_delay (unit[drive].type->side_time);
489 unit[drive].track = track;
490 if (cnt == 0) {
491 rel_fdc();
492 fd_deselect(drive);
493 return 1;
494 }
495 do {
496 prb &= ~DSKSTEP;
497 ciab.prb = prb;
498 prb |= DSKSTEP;
499 udelay (1);
500 ciab.prb = prb;
501 ms_delay (unit[drive].type->step_delay);
502 } while (--cnt != 0);
503 ms_delay (unit[drive].type->settle_time);
504
505 rel_fdc();
506 fd_deselect(drive);
507 return 1;
508 }
509
fd_get_drive_id(int drive)510 static unsigned long fd_get_drive_id(int drive)
511 {
512 int i;
513 ulong id = 0;
514
515 drive&=3;
516 get_fdc(drive);
517 /* set up for ID */
518 MOTOR_ON;
519 udelay(2);
520 SELECT(SELMASK(drive));
521 udelay(2);
522 DESELECT(SELMASK(drive));
523 udelay(2);
524 MOTOR_OFF;
525 udelay(2);
526 SELECT(SELMASK(drive));
527 udelay(2);
528 DESELECT(SELMASK(drive));
529 udelay(2);
530
531 /* loop and read disk ID */
532 for (i=0; i<32; i++) {
533 SELECT(SELMASK(drive));
534 udelay(2);
535
536 /* read and store value of DSKRDY */
537 id <<= 1;
538 id |= (ciaa.pra & DSKRDY) ? 0 : 1; /* cia regs are low-active! */
539
540 DESELECT(SELMASK(drive));
541 }
542
543 rel_fdc();
544
545 /*
546 * RB: At least A500/A2000's df0: don't identify themselves.
547 * As every (real) Amiga has at least a 3.5" DD drive as df0:
548 * we default to that if df0: doesn't identify as a certain
549 * type.
550 */
551 if(drive == 0 && id == FD_NODRIVE)
552 {
553 id = fd_def_df0;
554 printk(KERN_NOTICE "fd: drive 0 didn't identify, setting default %08lx\n", (ulong)fd_def_df0);
555 }
556 /* return the ID value */
557 return (id);
558 }
559
fd_block_done(int irq,void * dummy)560 static irqreturn_t fd_block_done(int irq, void *dummy)
561 {
562 if (block_flag)
563 custom.dsklen = 0x4000;
564
565 if (block_flag == 2) { /* writing */
566 writepending = 2;
567 post_write_timer.expires = jiffies + 1; /* at least 2 ms */
568 post_write_timer.data = selected;
569 add_timer(&post_write_timer);
570 }
571 else { /* reading */
572 block_flag = 0;
573 wake_up (&wait_fd_block);
574 }
575 return IRQ_HANDLED;
576 }
577
raw_read(int drive)578 static void raw_read(int drive)
579 {
580 drive&=3;
581 get_fdc(drive);
582 wait_event(wait_fd_block, !block_flag);
583 fd_select(drive);
584 /* setup adkcon bits correctly */
585 custom.adkcon = ADK_MSBSYNC;
586 custom.adkcon = ADK_SETCLR|ADK_WORDSYNC|ADK_FAST;
587
588 custom.dsksync = MFM_SYNC;
589
590 custom.dsklen = 0;
591 custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
592 custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
593 custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
594
595 block_flag = 1;
596
597 wait_event(wait_fd_block, !block_flag);
598
599 custom.dsklen = 0;
600 fd_deselect(drive);
601 rel_fdc();
602 }
603
raw_write(int drive)604 static int raw_write(int drive)
605 {
606 ushort adk;
607
608 drive&=3;
609 get_fdc(drive); /* corresponds to rel_fdc() in post_write() */
610 if ((ciaa.pra & DSKPROT) == 0) {
611 rel_fdc();
612 return 0;
613 }
614 wait_event(wait_fd_block, !block_flag);
615 fd_select(drive);
616 /* clear adkcon bits */
617 custom.adkcon = ADK_PRECOMP1|ADK_PRECOMP0|ADK_WORDSYNC|ADK_MSBSYNC;
618 /* set appropriate adkcon bits */
619 adk = ADK_SETCLR|ADK_FAST;
620 if ((ulong)unit[drive].track >= unit[drive].type->precomp2)
621 adk |= ADK_PRECOMP1;
622 else if ((ulong)unit[drive].track >= unit[drive].type->precomp1)
623 adk |= ADK_PRECOMP0;
624 custom.adkcon = adk;
625
626 custom.dsklen = DSKLEN_WRITE;
627 custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
628 custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
629 custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
630
631 block_flag = 2;
632 return 1;
633 }
634
635 /*
636 * to be called at least 2ms after the write has finished but before any
637 * other access to the hardware.
638 */
post_write(unsigned long drive)639 static void post_write (unsigned long drive)
640 {
641 #ifdef DEBUG
642 printk("post_write for drive %ld\n",drive);
643 #endif
644 drive &= 3;
645 custom.dsklen = 0;
646 block_flag = 0;
647 writepending = 0;
648 writefromint = 0;
649 unit[drive].dirty = 0;
650 wake_up(&wait_fd_block);
651 fd_deselect(drive);
652 rel_fdc(); /* corresponds to get_fdc() in raw_write */
653 }
654
655
656 /*
657 * The following functions are to convert the block contents into raw data
658 * written to disk and vice versa.
659 * (Add other formats here ;-))
660 */
661
scan_sync(unsigned long raw,unsigned long end)662 static unsigned long scan_sync(unsigned long raw, unsigned long end)
663 {
664 ushort *ptr = (ushort *)raw, *endp = (ushort *)end;
665
666 while (ptr < endp && *ptr++ != 0x4489)
667 ;
668 if (ptr < endp) {
669 while (*ptr == 0x4489 && ptr < endp)
670 ptr++;
671 return (ulong)ptr;
672 }
673 return 0;
674 }
675
checksum(unsigned long * addr,int len)676 static inline unsigned long checksum(unsigned long *addr, int len)
677 {
678 unsigned long csum = 0;
679
680 len /= sizeof(*addr);
681 while (len-- > 0)
682 csum ^= *addr++;
683 csum = ((csum>>1) & 0x55555555) ^ (csum & 0x55555555);
684
685 return csum;
686 }
687
decode(unsigned long * data,unsigned long * raw,int len)688 static unsigned long decode (unsigned long *data, unsigned long *raw,
689 int len)
690 {
691 ulong *odd, *even;
692
693 /* convert length from bytes to longwords */
694 len >>= 2;
695 odd = raw;
696 even = odd + len;
697
698 /* prepare return pointer */
699 raw += len * 2;
700
701 do {
702 *data++ = ((*odd++ & 0x55555555) << 1) | (*even++ & 0x55555555);
703 } while (--len != 0);
704
705 return (ulong)raw;
706 }
707
708 struct header {
709 unsigned char magic;
710 unsigned char track;
711 unsigned char sect;
712 unsigned char ord;
713 unsigned char labels[16];
714 unsigned long hdrchk;
715 unsigned long datachk;
716 };
717
amiga_read(int drive)718 static int amiga_read(int drive)
719 {
720 unsigned long raw;
721 unsigned long end;
722 int scnt;
723 unsigned long csum;
724 struct header hdr;
725
726 drive&=3;
727 raw = (long) raw_buf;
728 end = raw + unit[drive].type->read_size;
729
730 for (scnt = 0;scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
731 if (!(raw = scan_sync(raw, end))) {
732 printk (KERN_INFO "can't find sync for sector %d\n", scnt);
733 return MFM_NOSYNC;
734 }
735
736 raw = decode ((ulong *)&hdr.magic, (ulong *)raw, 4);
737 raw = decode ((ulong *)&hdr.labels, (ulong *)raw, 16);
738 raw = decode ((ulong *)&hdr.hdrchk, (ulong *)raw, 4);
739 raw = decode ((ulong *)&hdr.datachk, (ulong *)raw, 4);
740 csum = checksum((ulong *)&hdr,
741 (char *)&hdr.hdrchk-(char *)&hdr);
742
743 #ifdef DEBUG
744 printk ("(%x,%d,%d,%d) (%lx,%lx,%lx,%lx) %lx %lx\n",
745 hdr.magic, hdr.track, hdr.sect, hdr.ord,
746 *(ulong *)&hdr.labels[0], *(ulong *)&hdr.labels[4],
747 *(ulong *)&hdr.labels[8], *(ulong *)&hdr.labels[12],
748 hdr.hdrchk, hdr.datachk);
749 #endif
750
751 if (hdr.hdrchk != csum) {
752 printk(KERN_INFO "MFM_HEADER: %08lx,%08lx\n", hdr.hdrchk, csum);
753 return MFM_HEADER;
754 }
755
756 /* verify track */
757 if (hdr.track != unit[drive].track) {
758 printk(KERN_INFO "MFM_TRACK: %d, %d\n", hdr.track, unit[drive].track);
759 return MFM_TRACK;
760 }
761
762 raw = decode ((ulong *)(unit[drive].trackbuf + hdr.sect*512),
763 (ulong *)raw, 512);
764 csum = checksum((ulong *)(unit[drive].trackbuf + hdr.sect*512), 512);
765
766 if (hdr.datachk != csum) {
767 printk(KERN_INFO "MFM_DATA: (%x:%d:%d:%d) sc=%d %lx, %lx\n",
768 hdr.magic, hdr.track, hdr.sect, hdr.ord, scnt,
769 hdr.datachk, csum);
770 printk (KERN_INFO "data=(%lx,%lx,%lx,%lx)\n",
771 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[0],
772 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[1],
773 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[2],
774 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[3]);
775 return MFM_DATA;
776 }
777 }
778
779 return 0;
780 }
781
encode(unsigned long data,unsigned long * dest)782 static void encode(unsigned long data, unsigned long *dest)
783 {
784 unsigned long data2;
785
786 data &= 0x55555555;
787 data2 = data ^ 0x55555555;
788 data |= ((data2 >> 1) | 0x80000000) & (data2 << 1);
789
790 if (*(dest - 1) & 0x00000001)
791 data &= 0x7FFFFFFF;
792
793 *dest = data;
794 }
795
encode_block(unsigned long * dest,unsigned long * src,int len)796 static void encode_block(unsigned long *dest, unsigned long *src, int len)
797 {
798 int cnt, to_cnt = 0;
799 unsigned long data;
800
801 /* odd bits */
802 for (cnt = 0; cnt < len / 4; cnt++) {
803 data = src[cnt] >> 1;
804 encode(data, dest + to_cnt++);
805 }
806
807 /* even bits */
808 for (cnt = 0; cnt < len / 4; cnt++) {
809 data = src[cnt];
810 encode(data, dest + to_cnt++);
811 }
812 }
813
putsec(int disk,unsigned long * raw,int cnt)814 static unsigned long *putsec(int disk, unsigned long *raw, int cnt)
815 {
816 struct header hdr;
817 int i;
818
819 disk&=3;
820 *raw = (raw[-1]&1) ? 0x2AAAAAAA : 0xAAAAAAAA;
821 raw++;
822 *raw++ = 0x44894489;
823
824 hdr.magic = 0xFF;
825 hdr.track = unit[disk].track;
826 hdr.sect = cnt;
827 hdr.ord = unit[disk].dtype->sects * unit[disk].type->sect_mult - cnt;
828 for (i = 0; i < 16; i++)
829 hdr.labels[i] = 0;
830 hdr.hdrchk = checksum((ulong *)&hdr,
831 (char *)&hdr.hdrchk-(char *)&hdr);
832 hdr.datachk = checksum((ulong *)(unit[disk].trackbuf+cnt*512), 512);
833
834 encode_block(raw, (ulong *)&hdr.magic, 4);
835 raw += 2;
836 encode_block(raw, (ulong *)&hdr.labels, 16);
837 raw += 8;
838 encode_block(raw, (ulong *)&hdr.hdrchk, 4);
839 raw += 2;
840 encode_block(raw, (ulong *)&hdr.datachk, 4);
841 raw += 2;
842 encode_block(raw, (ulong *)(unit[disk].trackbuf+cnt*512), 512);
843 raw += 256;
844
845 return raw;
846 }
847
amiga_write(int disk)848 static void amiga_write(int disk)
849 {
850 unsigned int cnt;
851 unsigned long *ptr = (unsigned long *)raw_buf;
852
853 disk&=3;
854 /* gap space */
855 for (cnt = 0; cnt < 415 * unit[disk].type->sect_mult; cnt++)
856 *ptr++ = 0xaaaaaaaa;
857
858 /* sectors */
859 for (cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
860 ptr = putsec (disk, ptr, cnt);
861 *(ushort *)ptr = (ptr[-1]&1) ? 0x2AA8 : 0xAAA8;
862 }
863
864
865 struct dos_header {
866 unsigned char track, /* 0-80 */
867 side, /* 0-1 */
868 sec, /* 0-...*/
869 len_desc;/* 2 */
870 unsigned short crc; /* on 68000 we got an alignment problem,
871 but this compiler solves it by adding silently
872 adding a pad byte so data won't fit
873 and this took about 3h to discover.... */
874 unsigned char gap1[22]; /* for longword-alignedness (0x4e) */
875 };
876
877 /* crc routines are borrowed from the messydos-handler */
878
879 /* excerpt from the messydos-device
880 ; The CRC is computed not only over the actual data, but including
881 ; the SYNC mark (3 * $a1) and the 'ID/DATA - Address Mark' ($fe/$fb).
882 ; As we don't read or encode these fields into our buffers, we have to
883 ; preload the registers containing the CRC with the values they would have
884 ; after stepping over these fields.
885 ;
886 ; How CRCs "really" work:
887 ;
888 ; First, you should regard a bitstring as a series of coefficients of
889 ; polynomials. We calculate with these polynomials in modulo-2
890 ; arithmetic, in which both add and subtract are done the same as
891 ; exclusive-or. Now, we modify our data (a very long polynomial) in
892 ; such a way that it becomes divisible by the CCITT-standard 16-bit
893 ; 16 12 5
894 ; polynomial: x + x + x + 1, represented by $11021. The easiest
895 ; way to do this would be to multiply (using proper arithmetic) our
896 ; datablock with $11021. So we have:
897 ; data * $11021 =
898 ; data * ($10000 + $1021) =
899 ; data * $10000 + data * $1021
900 ; The left part of this is simple: Just add two 0 bytes. But then
901 ; the right part (data $1021) remains difficult and even could have
902 ; a carry into the left part. The solution is to use a modified
903 ; multiplication, which has a result that is not correct, but with
904 ; a difference of any multiple of $11021. We then only need to keep
905 ; the 16 least significant bits of the result.
906 ;
907 ; The following algorithm does this for us:
908 ;
909 ; unsigned char *data, c, crclo, crchi;
910 ; while (not done) {
911 ; c = *data++ + crchi;
912 ; crchi = (@ c) >> 8 + crclo;
913 ; crclo = @ c;
914 ; }
915 ;
916 ; Remember, + is done with EOR, the @ operator is in two tables (high
917 ; and low byte separately), which is calculated as
918 ;
919 ; $1021 * (c & $F0)
920 ; xor $1021 * (c & $0F)
921 ; xor $1021 * (c >> 4) (* is regular multiplication)
922 ;
923 ;
924 ; Anyway, the end result is the same as the remainder of the division of
925 ; the data by $11021. I am afraid I need to study theory a bit more...
926
927
928 my only works was to code this from manx to C....
929
930 */
931
dos_crc(void * data_a3,int data_d0,int data_d1,int data_d3)932 static ushort dos_crc(void * data_a3, int data_d0, int data_d1, int data_d3)
933 {
934 static unsigned char CRCTable1[] = {
935 0x00,0x10,0x20,0x30,0x40,0x50,0x60,0x70,0x81,0x91,0xa1,0xb1,0xc1,0xd1,0xe1,0xf1,
936 0x12,0x02,0x32,0x22,0x52,0x42,0x72,0x62,0x93,0x83,0xb3,0xa3,0xd3,0xc3,0xf3,0xe3,
937 0x24,0x34,0x04,0x14,0x64,0x74,0x44,0x54,0xa5,0xb5,0x85,0x95,0xe5,0xf5,0xc5,0xd5,
938 0x36,0x26,0x16,0x06,0x76,0x66,0x56,0x46,0xb7,0xa7,0x97,0x87,0xf7,0xe7,0xd7,0xc7,
939 0x48,0x58,0x68,0x78,0x08,0x18,0x28,0x38,0xc9,0xd9,0xe9,0xf9,0x89,0x99,0xa9,0xb9,
940 0x5a,0x4a,0x7a,0x6a,0x1a,0x0a,0x3a,0x2a,0xdb,0xcb,0xfb,0xeb,0x9b,0x8b,0xbb,0xab,
941 0x6c,0x7c,0x4c,0x5c,0x2c,0x3c,0x0c,0x1c,0xed,0xfd,0xcd,0xdd,0xad,0xbd,0x8d,0x9d,
942 0x7e,0x6e,0x5e,0x4e,0x3e,0x2e,0x1e,0x0e,0xff,0xef,0xdf,0xcf,0xbf,0xaf,0x9f,0x8f,
943 0x91,0x81,0xb1,0xa1,0xd1,0xc1,0xf1,0xe1,0x10,0x00,0x30,0x20,0x50,0x40,0x70,0x60,
944 0x83,0x93,0xa3,0xb3,0xc3,0xd3,0xe3,0xf3,0x02,0x12,0x22,0x32,0x42,0x52,0x62,0x72,
945 0xb5,0xa5,0x95,0x85,0xf5,0xe5,0xd5,0xc5,0x34,0x24,0x14,0x04,0x74,0x64,0x54,0x44,
946 0xa7,0xb7,0x87,0x97,0xe7,0xf7,0xc7,0xd7,0x26,0x36,0x06,0x16,0x66,0x76,0x46,0x56,
947 0xd9,0xc9,0xf9,0xe9,0x99,0x89,0xb9,0xa9,0x58,0x48,0x78,0x68,0x18,0x08,0x38,0x28,
948 0xcb,0xdb,0xeb,0xfb,0x8b,0x9b,0xab,0xbb,0x4a,0x5a,0x6a,0x7a,0x0a,0x1a,0x2a,0x3a,
949 0xfd,0xed,0xdd,0xcd,0xbd,0xad,0x9d,0x8d,0x7c,0x6c,0x5c,0x4c,0x3c,0x2c,0x1c,0x0c,
950 0xef,0xff,0xcf,0xdf,0xaf,0xbf,0x8f,0x9f,0x6e,0x7e,0x4e,0x5e,0x2e,0x3e,0x0e,0x1e
951 };
952
953 static unsigned char CRCTable2[] = {
954 0x00,0x21,0x42,0x63,0x84,0xa5,0xc6,0xe7,0x08,0x29,0x4a,0x6b,0x8c,0xad,0xce,0xef,
955 0x31,0x10,0x73,0x52,0xb5,0x94,0xf7,0xd6,0x39,0x18,0x7b,0x5a,0xbd,0x9c,0xff,0xde,
956 0x62,0x43,0x20,0x01,0xe6,0xc7,0xa4,0x85,0x6a,0x4b,0x28,0x09,0xee,0xcf,0xac,0x8d,
957 0x53,0x72,0x11,0x30,0xd7,0xf6,0x95,0xb4,0x5b,0x7a,0x19,0x38,0xdf,0xfe,0x9d,0xbc,
958 0xc4,0xe5,0x86,0xa7,0x40,0x61,0x02,0x23,0xcc,0xed,0x8e,0xaf,0x48,0x69,0x0a,0x2b,
959 0xf5,0xd4,0xb7,0x96,0x71,0x50,0x33,0x12,0xfd,0xdc,0xbf,0x9e,0x79,0x58,0x3b,0x1a,
960 0xa6,0x87,0xe4,0xc5,0x22,0x03,0x60,0x41,0xae,0x8f,0xec,0xcd,0x2a,0x0b,0x68,0x49,
961 0x97,0xb6,0xd5,0xf4,0x13,0x32,0x51,0x70,0x9f,0xbe,0xdd,0xfc,0x1b,0x3a,0x59,0x78,
962 0x88,0xa9,0xca,0xeb,0x0c,0x2d,0x4e,0x6f,0x80,0xa1,0xc2,0xe3,0x04,0x25,0x46,0x67,
963 0xb9,0x98,0xfb,0xda,0x3d,0x1c,0x7f,0x5e,0xb1,0x90,0xf3,0xd2,0x35,0x14,0x77,0x56,
964 0xea,0xcb,0xa8,0x89,0x6e,0x4f,0x2c,0x0d,0xe2,0xc3,0xa0,0x81,0x66,0x47,0x24,0x05,
965 0xdb,0xfa,0x99,0xb8,0x5f,0x7e,0x1d,0x3c,0xd3,0xf2,0x91,0xb0,0x57,0x76,0x15,0x34,
966 0x4c,0x6d,0x0e,0x2f,0xc8,0xe9,0x8a,0xab,0x44,0x65,0x06,0x27,0xc0,0xe1,0x82,0xa3,
967 0x7d,0x5c,0x3f,0x1e,0xf9,0xd8,0xbb,0x9a,0x75,0x54,0x37,0x16,0xf1,0xd0,0xb3,0x92,
968 0x2e,0x0f,0x6c,0x4d,0xaa,0x8b,0xe8,0xc9,0x26,0x07,0x64,0x45,0xa2,0x83,0xe0,0xc1,
969 0x1f,0x3e,0x5d,0x7c,0x9b,0xba,0xd9,0xf8,0x17,0x36,0x55,0x74,0x93,0xb2,0xd1,0xf0
970 };
971
972 /* look at the asm-code - what looks in C a bit strange is almost as good as handmade */
973 register int i;
974 register unsigned char *CRCT1, *CRCT2, *data, c, crch, crcl;
975
976 CRCT1=CRCTable1;
977 CRCT2=CRCTable2;
978 data=data_a3;
979 crcl=data_d1;
980 crch=data_d0;
981 for (i=data_d3; i>=0; i--) {
982 c = (*data++) ^ crch;
983 crch = CRCT1[c] ^ crcl;
984 crcl = CRCT2[c];
985 }
986 return (crch<<8)|crcl;
987 }
988
dos_hdr_crc(struct dos_header * hdr)989 static inline ushort dos_hdr_crc (struct dos_header *hdr)
990 {
991 return dos_crc(&(hdr->track), 0xb2, 0x30, 3); /* precomputed magic */
992 }
993
dos_data_crc(unsigned char * data)994 static inline ushort dos_data_crc(unsigned char *data)
995 {
996 return dos_crc(data, 0xe2, 0x95 ,511); /* precomputed magic */
997 }
998
dos_decode_byte(ushort word)999 static inline unsigned char dos_decode_byte(ushort word)
1000 {
1001 register ushort w2;
1002 register unsigned char byte;
1003 register unsigned char *dec = mfmdecode;
1004
1005 w2=word;
1006 w2>>=8;
1007 w2&=127;
1008 byte = dec[w2];
1009 byte <<= 4;
1010 w2 = word & 127;
1011 byte |= dec[w2];
1012 return byte;
1013 }
1014
dos_decode(unsigned char * data,unsigned short * raw,int len)1015 static unsigned long dos_decode(unsigned char *data, unsigned short *raw, int len)
1016 {
1017 int i;
1018
1019 for (i = 0; i < len; i++)
1020 *data++=dos_decode_byte(*raw++);
1021 return ((ulong)raw);
1022 }
1023
1024 #ifdef DEBUG
dbg(unsigned long ptr)1025 static void dbg(unsigned long ptr)
1026 {
1027 printk("raw data @%08lx: %08lx, %08lx ,%08lx, %08lx\n", ptr,
1028 ((ulong *)ptr)[0], ((ulong *)ptr)[1],
1029 ((ulong *)ptr)[2], ((ulong *)ptr)[3]);
1030 }
1031 #endif
1032
dos_read(int drive)1033 static int dos_read(int drive)
1034 {
1035 unsigned long end;
1036 unsigned long raw;
1037 int scnt;
1038 unsigned short crc,data_crc[2];
1039 struct dos_header hdr;
1040
1041 drive&=3;
1042 raw = (long) raw_buf;
1043 end = raw + unit[drive].type->read_size;
1044
1045 for (scnt=0; scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
1046 do { /* search for the right sync of each sec-hdr */
1047 if (!(raw = scan_sync (raw, end))) {
1048 printk(KERN_INFO "dos_read: no hdr sync on "
1049 "track %d, unit %d for sector %d\n",
1050 unit[drive].track,drive,scnt);
1051 return MFM_NOSYNC;
1052 }
1053 #ifdef DEBUG
1054 dbg(raw);
1055 #endif
1056 } while (*((ushort *)raw)!=0x5554); /* loop usually only once done */
1057 raw+=2; /* skip over headermark */
1058 raw = dos_decode((unsigned char *)&hdr,(ushort *) raw,8);
1059 crc = dos_hdr_crc(&hdr);
1060
1061 #ifdef DEBUG
1062 printk("(%3d,%d,%2d,%d) %x\n", hdr.track, hdr.side,
1063 hdr.sec, hdr.len_desc, hdr.crc);
1064 #endif
1065
1066 if (crc != hdr.crc) {
1067 printk(KERN_INFO "dos_read: MFM_HEADER %04x,%04x\n",
1068 hdr.crc, crc);
1069 return MFM_HEADER;
1070 }
1071 if (hdr.track != unit[drive].track/unit[drive].type->heads) {
1072 printk(KERN_INFO "dos_read: MFM_TRACK %d, %d\n",
1073 hdr.track,
1074 unit[drive].track/unit[drive].type->heads);
1075 return MFM_TRACK;
1076 }
1077
1078 if (hdr.side != unit[drive].track%unit[drive].type->heads) {
1079 printk(KERN_INFO "dos_read: MFM_SIDE %d, %d\n",
1080 hdr.side,
1081 unit[drive].track%unit[drive].type->heads);
1082 return MFM_TRACK;
1083 }
1084
1085 if (hdr.len_desc != 2) {
1086 printk(KERN_INFO "dos_read: unknown sector len "
1087 "descriptor %d\n", hdr.len_desc);
1088 return MFM_DATA;
1089 }
1090 #ifdef DEBUG
1091 printk("hdr accepted\n");
1092 #endif
1093 if (!(raw = scan_sync (raw, end))) {
1094 printk(KERN_INFO "dos_read: no data sync on track "
1095 "%d, unit %d for sector%d, disk sector %d\n",
1096 unit[drive].track, drive, scnt, hdr.sec);
1097 return MFM_NOSYNC;
1098 }
1099 #ifdef DEBUG
1100 dbg(raw);
1101 #endif
1102
1103 if (*((ushort *)raw)!=0x5545) {
1104 printk(KERN_INFO "dos_read: no data mark after "
1105 "sync (%d,%d,%d,%d) sc=%d\n",
1106 hdr.track,hdr.side,hdr.sec,hdr.len_desc,scnt);
1107 return MFM_NOSYNC;
1108 }
1109
1110 raw+=2; /* skip data mark (included in checksum) */
1111 raw = dos_decode((unsigned char *)(unit[drive].trackbuf + (hdr.sec - 1) * 512), (ushort *) raw, 512);
1112 raw = dos_decode((unsigned char *)data_crc,(ushort *) raw,4);
1113 crc = dos_data_crc(unit[drive].trackbuf + (hdr.sec - 1) * 512);
1114
1115 if (crc != data_crc[0]) {
1116 printk(KERN_INFO "dos_read: MFM_DATA (%d,%d,%d,%d) "
1117 "sc=%d, %x %x\n", hdr.track, hdr.side,
1118 hdr.sec, hdr.len_desc, scnt,data_crc[0], crc);
1119 printk(KERN_INFO "data=(%lx,%lx,%lx,%lx,...)\n",
1120 ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[0],
1121 ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[1],
1122 ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[2],
1123 ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[3]);
1124 return MFM_DATA;
1125 }
1126 }
1127 return 0;
1128 }
1129
dos_encode_byte(unsigned char byte)1130 static inline ushort dos_encode_byte(unsigned char byte)
1131 {
1132 register unsigned char *enc, b2, b1;
1133 register ushort word;
1134
1135 enc=mfmencode;
1136 b1=byte;
1137 b2=b1>>4;
1138 b1&=15;
1139 word=enc[b2] <<8 | enc [b1];
1140 return (word|((word&(256|64)) ? 0: 128));
1141 }
1142
dos_encode_block(ushort * dest,unsigned char * src,int len)1143 static void dos_encode_block(ushort *dest, unsigned char *src, int len)
1144 {
1145 int i;
1146
1147 for (i = 0; i < len; i++) {
1148 *dest=dos_encode_byte(*src++);
1149 *dest|=((dest[-1]&1)||(*dest&0x4000))? 0: 0x8000;
1150 dest++;
1151 }
1152 }
1153
ms_putsec(int drive,unsigned long * raw,int cnt)1154 static unsigned long *ms_putsec(int drive, unsigned long *raw, int cnt)
1155 {
1156 static struct dos_header hdr={0,0,0,2,0,
1157 {78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78}};
1158 int i;
1159 static ushort crc[2]={0,0x4e4e};
1160
1161 drive&=3;
1162 /* id gap 1 */
1163 /* the MFM word before is always 9254 */
1164 for(i=0;i<6;i++)
1165 *raw++=0xaaaaaaaa;
1166 /* 3 sync + 1 headermark */
1167 *raw++=0x44894489;
1168 *raw++=0x44895554;
1169
1170 /* fill in the variable parts of the header */
1171 hdr.track=unit[drive].track/unit[drive].type->heads;
1172 hdr.side=unit[drive].track%unit[drive].type->heads;
1173 hdr.sec=cnt+1;
1174 hdr.crc=dos_hdr_crc(&hdr);
1175
1176 /* header (without "magic") and id gap 2*/
1177 dos_encode_block((ushort *)raw,(unsigned char *) &hdr.track,28);
1178 raw+=14;
1179
1180 /*id gap 3 */
1181 for(i=0;i<6;i++)
1182 *raw++=0xaaaaaaaa;
1183
1184 /* 3 syncs and 1 datamark */
1185 *raw++=0x44894489;
1186 *raw++=0x44895545;
1187
1188 /* data */
1189 dos_encode_block((ushort *)raw,
1190 (unsigned char *)unit[drive].trackbuf+cnt*512,512);
1191 raw+=256;
1192
1193 /*data crc + jd's special gap (long words :-/) */
1194 crc[0]=dos_data_crc(unit[drive].trackbuf+cnt*512);
1195 dos_encode_block((ushort *) raw,(unsigned char *)crc,4);
1196 raw+=2;
1197
1198 /* data gap */
1199 for(i=0;i<38;i++)
1200 *raw++=0x92549254;
1201
1202 return raw; /* wrote 652 MFM words */
1203 }
1204
dos_write(int disk)1205 static void dos_write(int disk)
1206 {
1207 int cnt;
1208 unsigned long raw = (unsigned long) raw_buf;
1209 unsigned long *ptr=(unsigned long *)raw;
1210
1211 disk&=3;
1212 /* really gap4 + indexgap , but we write it first and round it up */
1213 for (cnt=0;cnt<425;cnt++)
1214 *ptr++=0x92549254;
1215
1216 /* the following is just guessed */
1217 if (unit[disk].type->sect_mult==2) /* check for HD-Disks */
1218 for(cnt=0;cnt<473;cnt++)
1219 *ptr++=0x92549254;
1220
1221 /* now the index marks...*/
1222 for (cnt=0;cnt<20;cnt++)
1223 *ptr++=0x92549254;
1224 for (cnt=0;cnt<6;cnt++)
1225 *ptr++=0xaaaaaaaa;
1226 *ptr++=0x52245224;
1227 *ptr++=0x52245552;
1228 for (cnt=0;cnt<20;cnt++)
1229 *ptr++=0x92549254;
1230
1231 /* sectors */
1232 for(cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
1233 ptr=ms_putsec(disk,ptr,cnt);
1234
1235 *(ushort *)ptr = 0xaaa8; /* MFM word before is always 0x9254 */
1236 }
1237
1238 /*
1239 * Here comes the high level stuff (i.e. the filesystem interface)
1240 * and helper functions.
1241 * Normally this should be the only part that has to be adapted to
1242 * different kernel versions.
1243 */
1244
1245 /* FIXME: this assumes the drive is still spinning -
1246 * which is only true if we complete writing a track within three seconds
1247 */
flush_track_callback(unsigned long nr)1248 static void flush_track_callback(unsigned long nr)
1249 {
1250 nr&=3;
1251 writefromint = 1;
1252 if (!try_fdc(nr)) {
1253 /* we might block in an interrupt, so try again later */
1254 flush_track_timer[nr].expires = jiffies + 1;
1255 add_timer(flush_track_timer + nr);
1256 return;
1257 }
1258 get_fdc(nr);
1259 (*unit[nr].dtype->write_fkt)(nr);
1260 if (!raw_write(nr)) {
1261 printk (KERN_NOTICE "floppy disk write protected\n");
1262 writefromint = 0;
1263 writepending = 0;
1264 }
1265 rel_fdc();
1266 }
1267
non_int_flush_track(unsigned long nr)1268 static int non_int_flush_track (unsigned long nr)
1269 {
1270 unsigned long flags;
1271
1272 nr&=3;
1273 writefromint = 0;
1274 del_timer(&post_write_timer);
1275 get_fdc(nr);
1276 if (!fd_motor_on(nr)) {
1277 writepending = 0;
1278 rel_fdc();
1279 return 0;
1280 }
1281 local_irq_save(flags);
1282 if (writepending != 2) {
1283 local_irq_restore(flags);
1284 (*unit[nr].dtype->write_fkt)(nr);
1285 if (!raw_write(nr)) {
1286 printk (KERN_NOTICE "floppy disk write protected "
1287 "in write!\n");
1288 writepending = 0;
1289 return 0;
1290 }
1291 wait_event(wait_fd_block, block_flag != 2);
1292 }
1293 else {
1294 local_irq_restore(flags);
1295 ms_delay(2); /* 2 ms post_write delay */
1296 post_write(nr);
1297 }
1298 rel_fdc();
1299 return 1;
1300 }
1301
get_track(int drive,int track)1302 static int get_track(int drive, int track)
1303 {
1304 int error, errcnt;
1305
1306 drive&=3;
1307 if (unit[drive].track == track)
1308 return 0;
1309 get_fdc(drive);
1310 if (!fd_motor_on(drive)) {
1311 rel_fdc();
1312 return -1;
1313 }
1314
1315 if (unit[drive].dirty == 1) {
1316 del_timer (flush_track_timer + drive);
1317 non_int_flush_track (drive);
1318 }
1319 errcnt = 0;
1320 while (errcnt < MAX_ERRORS) {
1321 if (!fd_seek(drive, track))
1322 return -1;
1323 raw_read(drive);
1324 error = (*unit[drive].dtype->read_fkt)(drive);
1325 if (error == 0) {
1326 rel_fdc();
1327 return 0;
1328 }
1329 /* Read Error Handling: recalibrate and try again */
1330 unit[drive].track = -1;
1331 errcnt++;
1332 }
1333 rel_fdc();
1334 return -1;
1335 }
1336
1337 /*
1338 * Round-robin between our available drives, doing one request from each
1339 */
set_next_request(void)1340 static struct request *set_next_request(void)
1341 {
1342 struct request_queue *q;
1343 int cnt = FD_MAX_UNITS;
1344 struct request *rq = NULL;
1345
1346 /* Find next queue we can dispatch from */
1347 fdc_queue = fdc_queue + 1;
1348 if (fdc_queue == FD_MAX_UNITS)
1349 fdc_queue = 0;
1350
1351 for(cnt = FD_MAX_UNITS; cnt > 0; cnt--) {
1352
1353 if (unit[fdc_queue].type->code == FD_NODRIVE) {
1354 if (++fdc_queue == FD_MAX_UNITS)
1355 fdc_queue = 0;
1356 continue;
1357 }
1358
1359 q = unit[fdc_queue].gendisk->queue;
1360 if (q) {
1361 rq = blk_fetch_request(q);
1362 if (rq)
1363 break;
1364 }
1365
1366 if (++fdc_queue == FD_MAX_UNITS)
1367 fdc_queue = 0;
1368 }
1369
1370 return rq;
1371 }
1372
redo_fd_request(void)1373 static void redo_fd_request(void)
1374 {
1375 struct request *rq;
1376 unsigned int cnt, block, track, sector;
1377 int drive;
1378 struct amiga_floppy_struct *floppy;
1379 char *data;
1380 unsigned long flags;
1381 int err;
1382
1383 next_req:
1384 rq = set_next_request();
1385 if (!rq) {
1386 /* Nothing left to do */
1387 return;
1388 }
1389
1390 floppy = rq->rq_disk->private_data;
1391 drive = floppy - unit;
1392
1393 next_segment:
1394 /* Here someone could investigate to be more efficient */
1395 for (cnt = 0, err = 0; cnt < blk_rq_cur_sectors(rq); cnt++) {
1396 #ifdef DEBUG
1397 printk("fd: sector %ld + %d requested for %s\n",
1398 blk_rq_pos(rq), cnt,
1399 (rq_data_dir(rq) == READ) ? "read" : "write");
1400 #endif
1401 block = blk_rq_pos(rq) + cnt;
1402 if ((int)block > floppy->blocks) {
1403 err = -EIO;
1404 break;
1405 }
1406
1407 track = block / (floppy->dtype->sects * floppy->type->sect_mult);
1408 sector = block % (floppy->dtype->sects * floppy->type->sect_mult);
1409 data = bio_data(rq->bio) + 512 * cnt;
1410 #ifdef DEBUG
1411 printk("access to track %d, sector %d, with buffer at "
1412 "0x%08lx\n", track, sector, data);
1413 #endif
1414
1415 if (get_track(drive, track) == -1) {
1416 err = -EIO;
1417 break;
1418 }
1419
1420 if (rq_data_dir(rq) == READ) {
1421 memcpy(data, floppy->trackbuf + sector * 512, 512);
1422 } else {
1423 memcpy(floppy->trackbuf + sector * 512, data, 512);
1424
1425 /* keep the drive spinning while writes are scheduled */
1426 if (!fd_motor_on(drive)) {
1427 err = -EIO;
1428 break;
1429 }
1430 /*
1431 * setup a callback to write the track buffer
1432 * after a short (1 tick) delay.
1433 */
1434 local_irq_save(flags);
1435
1436 floppy->dirty = 1;
1437 /* reset the timer */
1438 mod_timer (flush_track_timer + drive, jiffies + 1);
1439 local_irq_restore(flags);
1440 }
1441 }
1442
1443 if (__blk_end_request_cur(rq, err))
1444 goto next_segment;
1445 goto next_req;
1446 }
1447
do_fd_request(struct request_queue * q)1448 static void do_fd_request(struct request_queue * q)
1449 {
1450 redo_fd_request();
1451 }
1452
fd_getgeo(struct block_device * bdev,struct hd_geometry * geo)1453 static int fd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1454 {
1455 int drive = MINOR(bdev->bd_dev) & 3;
1456
1457 geo->heads = unit[drive].type->heads;
1458 geo->sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;
1459 geo->cylinders = unit[drive].type->tracks;
1460 return 0;
1461 }
1462
fd_locked_ioctl(struct block_device * bdev,fmode_t mode,unsigned int cmd,unsigned long param)1463 static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
1464 unsigned int cmd, unsigned long param)
1465 {
1466 struct amiga_floppy_struct *p = bdev->bd_disk->private_data;
1467 int drive = p - unit;
1468 static struct floppy_struct getprm;
1469 void __user *argp = (void __user *)param;
1470
1471 switch(cmd){
1472 case FDFMTBEG:
1473 get_fdc(drive);
1474 if (fd_ref[drive] > 1) {
1475 rel_fdc();
1476 return -EBUSY;
1477 }
1478 fsync_bdev(bdev);
1479 if (fd_motor_on(drive) == 0) {
1480 rel_fdc();
1481 return -ENODEV;
1482 }
1483 if (fd_calibrate(drive) == 0) {
1484 rel_fdc();
1485 return -ENXIO;
1486 }
1487 floppy_off(drive);
1488 rel_fdc();
1489 break;
1490 case FDFMTTRK:
1491 if (param < p->type->tracks * p->type->heads)
1492 {
1493 get_fdc(drive);
1494 if (fd_seek(drive,param) != 0){
1495 memset(p->trackbuf, FD_FILL_BYTE,
1496 p->dtype->sects * p->type->sect_mult * 512);
1497 non_int_flush_track(drive);
1498 }
1499 floppy_off(drive);
1500 rel_fdc();
1501 }
1502 else
1503 return -EINVAL;
1504 break;
1505 case FDFMTEND:
1506 floppy_off(drive);
1507 invalidate_bdev(bdev);
1508 break;
1509 case FDGETPRM:
1510 memset((void *)&getprm, 0, sizeof (getprm));
1511 getprm.track=p->type->tracks;
1512 getprm.head=p->type->heads;
1513 getprm.sect=p->dtype->sects * p->type->sect_mult;
1514 getprm.size=p->blocks;
1515 if (copy_to_user(argp, &getprm, sizeof(struct floppy_struct)))
1516 return -EFAULT;
1517 break;
1518 case FDSETPRM:
1519 case FDDEFPRM:
1520 return -EINVAL;
1521 case FDFLUSH: /* unconditionally, even if not needed */
1522 del_timer (flush_track_timer + drive);
1523 non_int_flush_track(drive);
1524 break;
1525 #ifdef RAW_IOCTL
1526 case IOCTL_RAW_TRACK:
1527 if (copy_to_user(argp, raw_buf, p->type->read_size))
1528 return -EFAULT;
1529 else
1530 return p->type->read_size;
1531 #endif
1532 default:
1533 printk(KERN_DEBUG "fd_ioctl: unknown cmd %d for drive %d.",
1534 cmd, drive);
1535 return -ENOSYS;
1536 }
1537 return 0;
1538 }
1539
fd_ioctl(struct block_device * bdev,fmode_t mode,unsigned int cmd,unsigned long param)1540 static int fd_ioctl(struct block_device *bdev, fmode_t mode,
1541 unsigned int cmd, unsigned long param)
1542 {
1543 int ret;
1544
1545 mutex_lock(&amiflop_mutex);
1546 ret = fd_locked_ioctl(bdev, mode, cmd, param);
1547 mutex_unlock(&amiflop_mutex);
1548
1549 return ret;
1550 }
1551
fd_probe(int dev)1552 static void fd_probe(int dev)
1553 {
1554 unsigned long code;
1555 int type;
1556 int drive;
1557
1558 drive = dev & 3;
1559 code = fd_get_drive_id(drive);
1560
1561 /* get drive type */
1562 for (type = 0; type < num_dr_types; type++)
1563 if (drive_types[type].code == code)
1564 break;
1565
1566 if (type >= num_dr_types) {
1567 printk(KERN_WARNING "fd_probe: unsupported drive type "
1568 "%08lx found\n", code);
1569 unit[drive].type = &drive_types[num_dr_types-1]; /* FD_NODRIVE */
1570 return;
1571 }
1572
1573 unit[drive].type = drive_types + type;
1574 unit[drive].track = -1;
1575
1576 unit[drive].disk = -1;
1577 unit[drive].motor = 0;
1578 unit[drive].busy = 0;
1579 unit[drive].status = -1;
1580 }
1581
1582 /*
1583 * floppy_open check for aliasing (/dev/fd0 can be the same as
1584 * /dev/PS0 etc), and disallows simultaneous access to the same
1585 * drive with different device numbers.
1586 */
floppy_open(struct block_device * bdev,fmode_t mode)1587 static int floppy_open(struct block_device *bdev, fmode_t mode)
1588 {
1589 int drive = MINOR(bdev->bd_dev) & 3;
1590 int system = (MINOR(bdev->bd_dev) & 4) >> 2;
1591 int old_dev;
1592 unsigned long flags;
1593
1594 mutex_lock(&amiflop_mutex);
1595 old_dev = fd_device[drive];
1596
1597 if (fd_ref[drive] && old_dev != system) {
1598 mutex_unlock(&amiflop_mutex);
1599 return -EBUSY;
1600 }
1601
1602 if (mode & (FMODE_READ|FMODE_WRITE)) {
1603 check_disk_change(bdev);
1604 if (mode & FMODE_WRITE) {
1605 int wrprot;
1606
1607 get_fdc(drive);
1608 fd_select (drive);
1609 wrprot = !(ciaa.pra & DSKPROT);
1610 fd_deselect (drive);
1611 rel_fdc();
1612
1613 if (wrprot) {
1614 mutex_unlock(&amiflop_mutex);
1615 return -EROFS;
1616 }
1617 }
1618 }
1619
1620 local_irq_save(flags);
1621 fd_ref[drive]++;
1622 fd_device[drive] = system;
1623 local_irq_restore(flags);
1624
1625 unit[drive].dtype=&data_types[system];
1626 unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
1627 data_types[system].sects*unit[drive].type->sect_mult;
1628 set_capacity(unit[drive].gendisk, unit[drive].blocks);
1629
1630 printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
1631 unit[drive].type->name, data_types[system].name);
1632
1633 mutex_unlock(&amiflop_mutex);
1634 return 0;
1635 }
1636
floppy_release(struct gendisk * disk,fmode_t mode)1637 static void floppy_release(struct gendisk *disk, fmode_t mode)
1638 {
1639 struct amiga_floppy_struct *p = disk->private_data;
1640 int drive = p - unit;
1641
1642 mutex_lock(&amiflop_mutex);
1643 if (unit[drive].dirty == 1) {
1644 del_timer (flush_track_timer + drive);
1645 non_int_flush_track (drive);
1646 }
1647
1648 if (!fd_ref[drive]--) {
1649 printk(KERN_CRIT "floppy_release with fd_ref == 0");
1650 fd_ref[drive] = 0;
1651 }
1652 #ifdef MODULE
1653 /* the mod_use counter is handled this way */
1654 floppy_off (drive | 0x40000000);
1655 #endif
1656 mutex_unlock(&amiflop_mutex);
1657 }
1658
1659 /*
1660 * check_events is never called from an interrupt, so we can relax a bit
1661 * here, sleep etc. Note that floppy-on tries to set current_DOR to point
1662 * to the desired drive, but it will probably not survive the sleep if
1663 * several floppies are used at the same time: thus the loop.
1664 */
amiga_check_events(struct gendisk * disk,unsigned int clearing)1665 static unsigned amiga_check_events(struct gendisk *disk, unsigned int clearing)
1666 {
1667 struct amiga_floppy_struct *p = disk->private_data;
1668 int drive = p - unit;
1669 int changed;
1670 static int first_time = 1;
1671
1672 if (first_time)
1673 changed = first_time--;
1674 else {
1675 get_fdc(drive);
1676 fd_select (drive);
1677 changed = !(ciaa.pra & DSKCHANGE);
1678 fd_deselect (drive);
1679 rel_fdc();
1680 }
1681
1682 if (changed) {
1683 fd_probe(drive);
1684 p->track = -1;
1685 p->dirty = 0;
1686 writepending = 0; /* if this was true before, too bad! */
1687 writefromint = 0;
1688 return DISK_EVENT_MEDIA_CHANGE;
1689 }
1690 return 0;
1691 }
1692
1693 static const struct block_device_operations floppy_fops = {
1694 .owner = THIS_MODULE,
1695 .open = floppy_open,
1696 .release = floppy_release,
1697 .ioctl = fd_ioctl,
1698 .getgeo = fd_getgeo,
1699 .check_events = amiga_check_events,
1700 };
1701
fd_probe_drives(void)1702 static int __init fd_probe_drives(void)
1703 {
1704 int drive,drives,nomem;
1705
1706 printk(KERN_INFO "FD: probing units\nfound ");
1707 drives=0;
1708 nomem=0;
1709 for(drive=0;drive<FD_MAX_UNITS;drive++) {
1710 struct gendisk *disk;
1711 fd_probe(drive);
1712 if (unit[drive].type->code == FD_NODRIVE)
1713 continue;
1714 disk = alloc_disk(1);
1715 if (!disk) {
1716 unit[drive].type->code = FD_NODRIVE;
1717 continue;
1718 }
1719 unit[drive].gendisk = disk;
1720
1721 disk->queue = blk_init_queue(do_fd_request, &amiflop_lock);
1722 if (!disk->queue) {
1723 unit[drive].type->code = FD_NODRIVE;
1724 continue;
1725 }
1726
1727 drives++;
1728 if ((unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL)) == NULL) {
1729 printk("no mem for ");
1730 unit[drive].type = &drive_types[num_dr_types - 1]; /* FD_NODRIVE */
1731 drives--;
1732 nomem = 1;
1733 }
1734 printk("fd%d ",drive);
1735 disk->major = FLOPPY_MAJOR;
1736 disk->first_minor = drive;
1737 disk->fops = &floppy_fops;
1738 sprintf(disk->disk_name, "fd%d", drive);
1739 disk->private_data = &unit[drive];
1740 set_capacity(disk, 880*2);
1741 add_disk(disk);
1742 }
1743 if ((drives > 0) || (nomem == 0)) {
1744 if (drives == 0)
1745 printk("no drives");
1746 printk("\n");
1747 return drives;
1748 }
1749 printk("\n");
1750 return -ENOMEM;
1751 }
1752
floppy_find(dev_t dev,int * part,void * data)1753 static struct kobject *floppy_find(dev_t dev, int *part, void *data)
1754 {
1755 int drive = *part & 3;
1756 if (unit[drive].type->code == FD_NODRIVE)
1757 return NULL;
1758 *part = 0;
1759 return get_disk(unit[drive].gendisk);
1760 }
1761
amiga_floppy_probe(struct platform_device * pdev)1762 static int __init amiga_floppy_probe(struct platform_device *pdev)
1763 {
1764 int i, ret;
1765
1766 if (register_blkdev(FLOPPY_MAJOR,"fd"))
1767 return -EBUSY;
1768
1769 ret = -ENOMEM;
1770 raw_buf = amiga_chip_alloc(RAW_BUF_SIZE, "Floppy");
1771 if (!raw_buf) {
1772 printk("fd: cannot get chip mem buffer\n");
1773 goto out_blkdev;
1774 }
1775
1776 ret = -EBUSY;
1777 if (request_irq(IRQ_AMIGA_DSKBLK, fd_block_done, 0, "floppy_dma", NULL)) {
1778 printk("fd: cannot get irq for dma\n");
1779 goto out_irq;
1780 }
1781
1782 if (request_irq(IRQ_AMIGA_CIAA_TB, ms_isr, 0, "floppy_timer", NULL)) {
1783 printk("fd: cannot get irq for timer\n");
1784 goto out_irq2;
1785 }
1786
1787 ret = -ENODEV;
1788 if (fd_probe_drives() < 1) /* No usable drives */
1789 goto out_probe;
1790
1791 blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
1792 floppy_find, NULL, NULL);
1793
1794 /* initialize variables */
1795 init_timer(&motor_on_timer);
1796 motor_on_timer.expires = 0;
1797 motor_on_timer.data = 0;
1798 motor_on_timer.function = motor_on_callback;
1799 for (i = 0; i < FD_MAX_UNITS; i++) {
1800 init_timer(&motor_off_timer[i]);
1801 motor_off_timer[i].expires = 0;
1802 motor_off_timer[i].data = i|0x80000000;
1803 motor_off_timer[i].function = fd_motor_off;
1804 init_timer(&flush_track_timer[i]);
1805 flush_track_timer[i].expires = 0;
1806 flush_track_timer[i].data = i;
1807 flush_track_timer[i].function = flush_track_callback;
1808
1809 unit[i].track = -1;
1810 }
1811
1812 init_timer(&post_write_timer);
1813 post_write_timer.expires = 0;
1814 post_write_timer.data = 0;
1815 post_write_timer.function = post_write;
1816
1817 for (i = 0; i < 128; i++)
1818 mfmdecode[i]=255;
1819 for (i = 0; i < 16; i++)
1820 mfmdecode[mfmencode[i]]=i;
1821
1822 /* make sure that disk DMA is enabled */
1823 custom.dmacon = DMAF_SETCLR | DMAF_DISK;
1824
1825 /* init ms timer */
1826 ciaa.crb = 8; /* one-shot, stop */
1827 return 0;
1828
1829 out_probe:
1830 free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1831 out_irq2:
1832 free_irq(IRQ_AMIGA_DSKBLK, NULL);
1833 out_irq:
1834 amiga_chip_free(raw_buf);
1835 out_blkdev:
1836 unregister_blkdev(FLOPPY_MAJOR,"fd");
1837 return ret;
1838 }
1839
1840 #if 0 /* not safe to unload */
1841 static int __exit amiga_floppy_remove(struct platform_device *pdev)
1842 {
1843 int i;
1844
1845 for( i = 0; i < FD_MAX_UNITS; i++) {
1846 if (unit[i].type->code != FD_NODRIVE) {
1847 struct request_queue *q = unit[i].gendisk->queue;
1848 del_gendisk(unit[i].gendisk);
1849 put_disk(unit[i].gendisk);
1850 kfree(unit[i].trackbuf);
1851 if (q)
1852 blk_cleanup_queue(q);
1853 }
1854 }
1855 blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
1856 free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1857 free_irq(IRQ_AMIGA_DSKBLK, NULL);
1858 custom.dmacon = DMAF_DISK; /* disable DMA */
1859 amiga_chip_free(raw_buf);
1860 unregister_blkdev(FLOPPY_MAJOR, "fd");
1861 }
1862 #endif
1863
1864 static struct platform_driver amiga_floppy_driver = {
1865 .driver = {
1866 .name = "amiga-floppy",
1867 .owner = THIS_MODULE,
1868 },
1869 };
1870
amiga_floppy_init(void)1871 static int __init amiga_floppy_init(void)
1872 {
1873 return platform_driver_probe(&amiga_floppy_driver, amiga_floppy_probe);
1874 }
1875
1876 module_init(amiga_floppy_init);
1877
1878 #ifndef MODULE
amiga_floppy_setup(char * str)1879 static int __init amiga_floppy_setup (char *str)
1880 {
1881 int n;
1882 if (!MACH_IS_AMIGA)
1883 return 0;
1884 if (!get_option(&str, &n))
1885 return 0;
1886 printk (KERN_INFO "amiflop: Setting default df0 to %x\n", n);
1887 fd_def_df0 = n;
1888 return 1;
1889 }
1890
1891 __setup("floppy=", amiga_floppy_setup);
1892 #endif
1893
1894 MODULE_ALIAS("platform:amiga-floppy");
1895