File: /usr/src/linux/drivers/block/amiflop.c
1 /*
2 * linux/amiga/amiflop.c
3 *
4 * Copyright (C) 1993 Greg Harp
5 * Portions of this driver are based on code contributed by Brad Pepers
6 *
7 * revised 28.5.95 by Joerg Dorchain
8 * - now no bugs(?) any more for both HD & DD
9 * - added support for 40 Track 5.25" drives, 80-track hopefully behaves
10 * like 3.5" dd (no way to test - are there any 5.25" drives out there
11 * that work on an A4000?)
12 * - wrote formatting routine (maybe dirty, but works)
13 *
14 * june/july 1995 added ms-dos support by Joerg Dorchain
15 * (portions based on messydos.device and various contributors)
16 * - currently only 9 and 18 sector disks
17 *
18 * - fixed a bug with the internal trackbuffer when using multiple
19 * disks the same time
20 * - made formatting a bit safer
21 * - added command line and machine based default for "silent" df0
22 *
23 * december 1995 adapted for 1.2.13pl4 by Joerg Dorchain
24 * - works but I think it's inefficient. (look in redo_fd_request)
25 * But the changes were very efficient. (only three and a half lines)
26 *
27 * january 1996 added special ioctl for tracking down read/write problems
28 * - usage ioctl(d, RAW_TRACK, ptr); the raw track buffer (MFM-encoded data
29 * is copied to area. (area should be large enough since no checking is
30 * done - 30K is currently sufficient). return the actual size of the
31 * trackbuffer
32 * - replaced udelays() by a timer (CIAA timer B) for the waits
33 * needed for the disk mechanic.
34 *
35 * february 1996 fixed error recovery and multiple disk access
36 * - both got broken the first time I tampered with the driver :-(
37 * - still not safe, but better than before
38 *
39 * revised Marts 3rd, 1996 by Jes Sorensen for use in the 1.3.28 kernel.
40 * - Minor changes to accept the kdev_t.
41 * - Replaced some more udelays with ms_delays. Udelay is just a loop,
42 * and so the delay will be different depending on the given
43 * processor :-(
44 * - The driver could use a major cleanup because of the new
45 * major/minor handling that came with kdev_t. It seems to work for
46 * the time being, but I can't guarantee that it will stay like
47 * that when we start using 16 (24?) bit minors.
48 *
49 * restructured jan 1997 by Joerg Dorchain
50 * - Fixed Bug accessing multiple disks
51 * - some code cleanup
52 * - added trackbuffer for each drive to speed things up
53 * - fixed some race conditions (who finds the next may send it to me ;-)
54 */
55
56 #include <linux/module.h>
57
58 #include <linux/sched.h>
59 #include <linux/fs.h>
60 #include <linux/fcntl.h>
61 #include <linux/kernel.h>
62 #include <linux/timer.h>
63 #include <linux/fd.h>
64 #include <linux/hdreg.h>
65 #include <linux/errno.h>
66 #include <linux/types.h>
67 #include <linux/delay.h>
68 #include <linux/string.h>
69 #include <linux/slab.h>
70 #include <linux/init.h>
71 #include <linux/amifdreg.h>
72 #include <linux/amifd.h>
73 #include <linux/ioport.h>
74
75 #include <asm/setup.h>
76 #include <asm/uaccess.h>
77 #include <asm/amigahw.h>
78 #include <asm/amigaints.h>
79 #include <asm/irq.h>
80
81 #define MAJOR_NR FLOPPY_MAJOR
82 #include <linux/blk.h>
83
84 #undef DEBUG /* print _LOTS_ of infos */
85
86 #define RAW_IOCTL
87 #ifdef RAW_IOCTL
88 #define IOCTL_RAW_TRACK 0x5254524B /* 'RTRK' */
89 #endif
90
91 /*
92 * Defines
93 */
94
95 /*
96 * Error codes
97 */
98 #define FD_OK 0 /* operation succeeded */
99 #define FD_ERROR -1 /* general error (seek, read, write, etc) */
100 #define FD_NOUNIT 1 /* unit does not exist */
101 #define FD_UNITBUSY 2 /* unit already active */
102 #define FD_NOTACTIVE 3 /* unit is not active */
103 #define FD_NOTREADY 4 /* unit is not ready (motor not on/no disk) */
104
105 #define MFM_NOSYNC 1
106 #define MFM_HEADER 2
107 #define MFM_DATA 3
108 #define MFM_TRACK 4
109
110 /*
111 * Floppy ID values
112 */
113 #define FD_NODRIVE 0x00000000 /* response when no unit is present */
114 #define FD_DD_3 0xffffffff /* double-density 3.5" (880K) drive */
115 #define FD_HD_3 0x55555555 /* high-density 3.5" (1760K) drive */
116 #define FD_DD_5 0xaaaaaaaa /* double-density 5.25" (440K) drive */
117
118 static long int fd_def_df0 = FD_DD_3; /* default for df0 if it doesn't identify */
119
120 MODULE_PARM(fd_def_df0,"l");
121 MODULE_LICENSE("GPL");
122
123 /*
124 * Macros
125 */
126 #define MOTOR_ON (ciab.prb &= ~DSKMOTOR)
127 #define MOTOR_OFF (ciab.prb |= DSKMOTOR)
128 #define SELECT(mask) (ciab.prb &= ~mask)
129 #define DESELECT(mask) (ciab.prb |= mask)
130 #define SELMASK(drive) (1 << (3 + (drive & 3)))
131
132 static struct fd_drive_type drive_types[] = {
133 /* code name tr he rdsz wrsz sm pc1 pc2 sd st st*/
134 /* warning: times are now in milliseconds (ms) */
135 { FD_DD_3, "DD 3.5", 80, 2, 14716, 13630, 1, 80,161, 3, 18, 1},
136 { FD_HD_3, "HD 3.5", 80, 2, 28344, 27258, 2, 80,161, 3, 18, 1},
137 { FD_DD_5, "DD 5.25", 40, 2, 14716, 13630, 1, 40, 81, 6, 30, 2},
138 { FD_NODRIVE, "No Drive", 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
139 };
140 static int num_dr_types = sizeof(drive_types) / sizeof(drive_types[0]);
141
142 /* defaults for 3 1/2" HD-Disks */
143 static int floppy_sizes[256]={880,880,880,880,720,720,720,720,};
144 static int floppy_blocksizes[256];
145 /* hardsector size assumed to be 512 */
146
147 static int amiga_read(int), dos_read(int);
148 static void amiga_write(int), dos_write(int);
149 static struct fd_data_type data_types[] = {
150 { "Amiga", 11 , amiga_read, amiga_write},
151 { "MS-Dos", 9, dos_read, dos_write}
152 };
153
154 /* current info on each unit */
155 static struct amiga_floppy_struct unit[FD_MAX_UNITS];
156
157 static struct timer_list flush_track_timer[FD_MAX_UNITS];
158 static struct timer_list post_write_timer;
159 static struct timer_list motor_on_timer;
160 static struct timer_list motor_off_timer[FD_MAX_UNITS];
161 static int on_attempts;
162
163 /* Synchronization of FDC access */
164 /* request loop (trackbuffer) */
165 static volatile int fdc_busy = -1;
166 static volatile int fdc_nested;
167 static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
168
169 static DECLARE_WAIT_QUEUE_HEAD(motor_wait);
170
171 static volatile int selected = -1; /* currently selected drive */
172
173 static int writepending;
174 static int writefromint;
175 static char *raw_buf;
176
177 #define RAW_BUF_SIZE 30000 /* size of raw disk data */
178
179 /*
180 * These are global variables, as that's the easiest way to give
181 * information to interrupts. They are the data used for the current
182 * request.
183 */
184 static volatile char block_flag;
185 static DECLARE_WAIT_QUEUE_HEAD(wait_fd_block);
186
187 /* MS-Dos MFM Coding tables (should go quick and easy) */
188 static unsigned char mfmencode[16]={
189 0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15,
190 0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55
191 };
192 static unsigned char mfmdecode[128];
193
194 /* floppy internal millisecond timer stuff */
195 static volatile int ms_busy = -1;
196 static DECLARE_WAIT_QUEUE_HEAD(ms_wait);
197 #define MS_TICKS ((amiga_eclock+50)/1000)
198
199 /*
200 * Note that MAX_ERRORS=X doesn't imply that we retry every bad read
201 * max X times - some types of errors increase the errorcount by 2 or
202 * even 3, so we might actually retry only X/2 times before giving up.
203 */
204 #define MAX_ERRORS 12
205
206 /* Prevent "aliased" accesses. */
207 static int fd_ref[4] = { 0,0,0,0 };
208 static int fd_device[4] = { 0,0,0,0 };
209
210 /*
211 * Current device number. Taken either from the block header or from the
212 * format request descriptor.
213 */
214 #define CURRENT_DEVICE (CURRENT->rq_dev)
215
216 /* Current error count. */
217 #define CURRENT_ERRORS (CURRENT->errors)
218
219
220
221 /*
222 * Here come the actual hardware access and helper functions.
223 * They are not reentrant and single threaded because all drives
224 * share the same hardware and the same trackbuffer.
225 */
226
227 /* Milliseconds timer */
228
229 static void ms_isr(int irq, void *dummy, struct pt_regs *fp)
230 {
231 ms_busy = -1;
232 wake_up(&ms_wait);
233 }
234
235 /* all waits are queued up
236 A more generic routine would do a schedule a la timer.device */
237 static void ms_delay(int ms)
238 {
239 unsigned long flags;
240 int ticks;
241 if (ms > 0) {
242 save_flags(flags);
243 cli();
244 while (ms_busy == 0)
245 sleep_on(&ms_wait);
246 ms_busy = 0;
247 restore_flags(flags);
248 ticks = MS_TICKS*ms-1;
249 ciaa.tblo=ticks%256;
250 ciaa.tbhi=ticks/256;
251 ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */
252 sleep_on(&ms_wait);
253 }
254 }
255
256 /* Hardware semaphore */
257
258 /* returns true when we would get the semaphore */
259 static inline int try_fdc(int drive)
260 {
261 drive &= 3;
262 return ((fdc_busy < 0) || (fdc_busy == drive));
263 }
264
265 static void get_fdc(int drive)
266 {
267 unsigned long flags;
268
269 drive &= 3;
270 #ifdef DEBUG
271 printk("get_fdc: drive %d fdc_busy %d fdc_nested %d\n",drive,fdc_busy,fdc_nested);
272 #endif
273 save_flags(flags);
274 cli();
275 while (!try_fdc(drive))
276 sleep_on(&fdc_wait);
277 fdc_busy = drive;
278 fdc_nested++;
279 restore_flags(flags);
280 }
281
282 static inline void rel_fdc(void)
283 {
284 #ifdef DEBUG
285 if (fdc_nested == 0)
286 printk("fd: unmatched rel_fdc\n");
287 printk("rel_fdc: fdc_busy %d fdc_nested %d\n",fdc_busy,fdc_nested);
288 #endif
289 fdc_nested--;
290 if (fdc_nested == 0) {
291 fdc_busy = -1;
292 wake_up(&fdc_wait);
293 }
294 }
295
296 static void fd_select (int drive)
297 {
298 unsigned char prb = ~0;
299
300 drive&=3;
301 #ifdef DEBUG
302 printk("selecting %d\n",drive);
303 #endif
304 if (drive == selected)
305 return;
306 get_fdc(drive);
307 selected = drive;
308
309 if (unit[drive].track % 2 != 0)
310 prb &= ~DSKSIDE;
311 if (unit[drive].motor == 1)
312 prb &= ~DSKMOTOR;
313 ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
314 ciab.prb = prb;
315 prb &= ~SELMASK(drive);
316 ciab.prb = prb;
317 rel_fdc();
318 }
319
320 static void fd_deselect (int drive)
321 {
322 unsigned char prb;
323 unsigned long flags;
324
325 drive&=3;
326 #ifdef DEBUG
327 printk("deselecting %d\n",drive);
328 #endif
329 if (drive != selected) {
330 printk(KERN_WARNING "Deselecting drive %d while %d was selected!\n",drive,selected);
331 return;
332 }
333
334 get_fdc(drive);
335 save_flags (flags);
336 sti();
337
338 selected = -1;
339
340 prb = ciab.prb;
341 prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
342 ciab.prb = prb;
343
344 restore_flags (flags);
345 rel_fdc();
346
347 }
348
349 static void motor_on_callback(unsigned long nr)
350 {
351 if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {
352 wake_up (&motor_wait);
353 } else {
354 motor_on_timer.expires = jiffies + HZ/10;
355 add_timer(&motor_on_timer);
356 }
357 }
358
359 static int fd_motor_on(int nr)
360 {
361 nr &= 3;
362
363 del_timer(motor_off_timer + nr);
364
365 if (!unit[nr].motor) {
366 unit[nr].motor = 1;
367 fd_select(nr);
368
369 del_timer(&motor_on_timer);
370 motor_on_timer.data = nr;
371 motor_on_timer.expires = jiffies + HZ/2;
372 add_timer(&motor_on_timer);
373
374 on_attempts = 10;
375 sleep_on (&motor_wait);
376 fd_deselect(nr);
377 }
378
379 if (on_attempts == 0) {
380 on_attempts = -1;
381 #if 0
382 printk (KERN_ERR "motor_on failed, turning motor off\n");
383 fd_motor_off (nr);
384 return 0;
385 #else
386 printk (KERN_WARNING "DSKRDY not set after 1.5 seconds - assuming drive is spinning notwithstanding\n");
387 #endif
388 }
389
390 return 1;
391 }
392
393 static void fd_motor_off(unsigned long drive)
394 {
395 long calledfromint;
396 #ifdef MODULE
397 long decusecount;
398
399 decusecount = drive & 0x40000000;
400 #endif
401 calledfromint = drive & 0x80000000;
402 drive&=3;
403 if (calledfromint && !try_fdc(drive)) {
404 /* We would be blocked in an interrupt, so try again later */
405 motor_off_timer[drive].expires = jiffies + 1;
406 add_timer(motor_off_timer + drive);
407 return;
408 }
409 unit[drive].motor = 0;
410 fd_select(drive);
411 udelay (1);
412 fd_deselect(drive);
413
414 #ifdef MODULE
415 /*
416 this is the last interrupt for any drive access, happens after
417 release (from floppy_off). So we have to wait until now to decrease
418 the use count.
419 */
420 if (decusecount)
421 MOD_DEC_USE_COUNT;
422 #endif
423 }
424
425 static void floppy_off (unsigned int nr)
426 {
427 int drive;
428
429 drive = nr & 3;
430 del_timer(motor_off_timer + drive);
431 motor_off_timer[drive].expires = jiffies + 3*HZ;
432 /* called this way it is always from interrupt */
433 motor_off_timer[drive].data = nr | 0x80000000;
434 add_timer(motor_off_timer + nr);
435 }
436
437 static int fd_calibrate(int drive)
438 {
439 unsigned char prb;
440 int n;
441
442 drive &= 3;
443 get_fdc(drive);
444 if (!fd_motor_on (drive))
445 return 0;
446 fd_select (drive);
447 prb = ciab.prb;
448 prb |= DSKSIDE;
449 prb &= ~DSKDIREC;
450 ciab.prb = prb;
451 for (n = unit[drive].type->tracks/2; n != 0; --n) {
452 if (ciaa.pra & DSKTRACK0)
453 break;
454 prb &= ~DSKSTEP;
455 ciab.prb = prb;
456 prb |= DSKSTEP;
457 udelay (2);
458 ciab.prb = prb;
459 ms_delay(unit[drive].type->step_delay);
460 }
461 ms_delay (unit[drive].type->settle_time);
462 prb |= DSKDIREC;
463 n = unit[drive].type->tracks + 20;
464 for (;;) {
465 prb &= ~DSKSTEP;
466 ciab.prb = prb;
467 prb |= DSKSTEP;
468 udelay (2);
469 ciab.prb = prb;
470 ms_delay(unit[drive].type->step_delay + 1);
471 if ((ciaa.pra & DSKTRACK0) == 0)
472 break;
473 if (--n == 0) {
474 printk (KERN_ERR "fd%d: calibrate failed, turning motor off\n", drive);
475 fd_motor_off (drive);
476 unit[drive].track = -1;
477 rel_fdc();
478 return 0;
479 }
480 }
481 unit[drive].track = 0;
482 ms_delay(unit[drive].type->settle_time);
483
484 rel_fdc();
485 fd_deselect(drive);
486 return 1;
487 }
488
489 static int fd_seek(int drive, int track)
490 {
491 unsigned char prb;
492 int cnt;
493
494 #ifdef DEBUG
495 printk("seeking drive %d to track %d\n",drive,track);
496 #endif
497 drive &= 3;
498 get_fdc(drive);
499 if (unit[drive].track == track) {
500 rel_fdc();
501 return 1;
502 }
503 if (!fd_motor_on(drive)) {
504 rel_fdc();
505 return 0;
506 }
507 if (unit[drive].track < 0 && !fd_calibrate(drive)) {
508 rel_fdc();
509 return 0;
510 }
511
512 fd_select (drive);
513 cnt = unit[drive].track/2 - track/2;
514 prb = ciab.prb;
515 prb |= DSKSIDE | DSKDIREC;
516 if (track % 2 != 0)
517 prb &= ~DSKSIDE;
518 if (cnt < 0) {
519 cnt = - cnt;
520 prb &= ~DSKDIREC;
521 }
522 ciab.prb = prb;
523 if (track % 2 != unit[drive].track % 2)
524 ms_delay (unit[drive].type->side_time);
525 unit[drive].track = track;
526 if (cnt == 0) {
527 rel_fdc();
528 fd_deselect(drive);
529 return 1;
530 }
531 do {
532 prb &= ~DSKSTEP;
533 ciab.prb = prb;
534 prb |= DSKSTEP;
535 udelay (1);
536 ciab.prb = prb;
537 ms_delay (unit[drive].type->step_delay);
538 } while (--cnt != 0);
539 ms_delay (unit[drive].type->settle_time);
540
541 rel_fdc();
542 fd_deselect(drive);
543 return 1;
544 }
545
546 static unsigned long fd_get_drive_id(int drive)
547 {
548 int i;
549 ulong id = 0;
550
551 drive&=3;
552 get_fdc(drive);
553 /* set up for ID */
554 MOTOR_ON;
555 udelay(2);
556 SELECT(SELMASK(drive));
557 udelay(2);
558 DESELECT(SELMASK(drive));
559 udelay(2);
560 MOTOR_OFF;
561 udelay(2);
562 SELECT(SELMASK(drive));
563 udelay(2);
564 DESELECT(SELMASK(drive));
565 udelay(2);
566
567 /* loop and read disk ID */
568 for (i=0; i<32; i++) {
569 SELECT(SELMASK(drive));
570 udelay(2);
571
572 /* read and store value of DSKRDY */
573 id <<= 1;
574 id |= (ciaa.pra & DSKRDY) ? 0 : 1; /* cia regs are low-active! */
575
576 DESELECT(SELMASK(drive));
577 }
578
579 rel_fdc();
580
581 /*
582 * RB: At least A500/A2000's df0: don't identify themselves.
583 * As every (real) Amiga has at least a 3.5" DD drive as df0:
584 * we default to that if df0: doesn't identify as a certain
585 * type.
586 */
587 if(drive == 0 && id == FD_NODRIVE)
588 {
589 id = fd_def_df0;
590 printk(KERN_NOTICE "fd: drive 0 didn't identify, setting default %08lx\n", (ulong)fd_def_df0);
591 }
592 /* return the ID value */
593 return (id);
594 }
595
596 static void fd_block_done(int irq, void *dummy, struct pt_regs *fp)
597 {
598 if (block_flag)
599 custom.dsklen = 0x4000;
600
601 if (block_flag == 2) { /* writing */
602 writepending = 2;
603 post_write_timer.expires = jiffies + 1; /* at least 2 ms */
604 post_write_timer.data = selected;
605 add_timer(&post_write_timer);
606 }
607 else { /* reading */
608 block_flag = 0;
609 wake_up (&wait_fd_block);
610 }
611 }
612
613 static void raw_read(int drive)
614 {
615 drive&=3;
616 get_fdc(drive);
617 while (block_flag)
618 sleep_on(&wait_fd_block);
619 fd_select(drive);
620 /* setup adkcon bits correctly */
621 custom.adkcon = ADK_MSBSYNC;
622 custom.adkcon = ADK_SETCLR|ADK_WORDSYNC|ADK_FAST;
623
624 custom.dsksync = MFM_SYNC;
625
626 custom.dsklen = 0;
627 custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
628 custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
629 custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
630
631 block_flag = 1;
632
633 while (block_flag)
634 sleep_on (&wait_fd_block);
635
636 custom.dsklen = 0;
637 fd_deselect(drive);
638 rel_fdc();
639 }
640
641 static int raw_write(int drive)
642 {
643 ushort adk;
644
645 drive&=3;
646 get_fdc(drive); /* corresponds to rel_fdc() in post_write() */
647 if ((ciaa.pra & DSKPROT) == 0) {
648 rel_fdc();
649 return 0;
650 }
651 while (block_flag)
652 sleep_on(&wait_fd_block);
653 fd_select(drive);
654 /* clear adkcon bits */
655 custom.adkcon = ADK_PRECOMP1|ADK_PRECOMP0|ADK_WORDSYNC|ADK_MSBSYNC;
656 /* set appropriate adkcon bits */
657 adk = ADK_SETCLR|ADK_FAST;
658 if ((ulong)unit[drive].track >= unit[drive].type->precomp2)
659 adk |= ADK_PRECOMP1;
660 else if ((ulong)unit[drive].track >= unit[drive].type->precomp1)
661 adk |= ADK_PRECOMP0;
662 custom.adkcon = adk;
663
664 custom.dsklen = DSKLEN_WRITE;
665 custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
666 custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
667 custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
668
669 block_flag = 2;
670 return 1;
671 }
672
673 /*
674 * to be called at least 2ms after the write has finished but before any
675 * other access to the hardware.
676 */
677 static void post_write (unsigned long drive)
678 {
679 #ifdef DEBUG
680 printk("post_write for drive %ld\n",drive);
681 #endif
682 drive &= 3;
683 custom.dsklen = 0;
684 block_flag = 0;
685 writepending = 0;
686 writefromint = 0;
687 unit[drive].dirty = 0;
688 wake_up(&wait_fd_block);
689 fd_deselect(drive);
690 rel_fdc(); /* corresponds to get_fdc() in raw_write */
691 }
692
693
694 /*
695 * The following functions are to convert the block contents into raw data
696 * written to disk and vice versa.
697 * (Add other formats here ;-))
698 */
699
700 static unsigned long scan_sync(unsigned long raw, unsigned long end)
701 {
702 ushort *ptr = (ushort *)raw, *endp = (ushort *)end;
703
704 while (ptr < endp && *ptr++ != 0x4489)
705 ;
706 if (ptr < endp) {
707 while (*ptr == 0x4489 && ptr < endp)
708 ptr++;
709 return (ulong)ptr;
710 }
711 return 0;
712 }
713
714 static inline unsigned long checksum(unsigned long *addr, int len)
715 {
716 unsigned long csum = 0;
717
718 len /= sizeof(*addr);
719 while (len-- > 0)
720 csum ^= *addr++;
721 csum = ((csum>>1) & 0x55555555) ^ (csum & 0x55555555);
722
723 return csum;
724 }
725
726 static unsigned long decode (unsigned long *data, unsigned long *raw,
727 int len)
728 {
729 ulong *odd, *even;
730
731 /* convert length from bytes to longwords */
732 len >>= 2;
733 odd = raw;
734 even = odd + len;
735
736 /* prepare return pointer */
737 raw += len * 2;
738
739 do {
740 *data++ = ((*odd++ & 0x55555555) << 1) | (*even++ & 0x55555555);
741 } while (--len != 0);
742
743 return (ulong)raw;
744 }
745
746 struct header {
747 unsigned char magic;
748 unsigned char track;
749 unsigned char sect;
750 unsigned char ord;
751 unsigned char labels[16];
752 unsigned long hdrchk;
753 unsigned long datachk;
754 };
755
756 static int amiga_read(int drive)
757 {
758 unsigned long raw;
759 unsigned long end;
760 int scnt;
761 unsigned long csum;
762 struct header hdr;
763
764 drive&=3;
765 raw = (long) raw_buf;
766 end = raw + unit[drive].type->read_size;
767
768 for (scnt = 0;scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
769 if (!(raw = scan_sync(raw, end))) {
770 printk (KERN_INFO "can't find sync for sector %d\n", scnt);
771 return MFM_NOSYNC;
772 }
773
774 raw = decode ((ulong *)&hdr.magic, (ulong *)raw, 4);
775 raw = decode ((ulong *)&hdr.labels, (ulong *)raw, 16);
776 raw = decode ((ulong *)&hdr.hdrchk, (ulong *)raw, 4);
777 raw = decode ((ulong *)&hdr.datachk, (ulong *)raw, 4);
778 csum = checksum((ulong *)&hdr,
779 (char *)&hdr.hdrchk-(char *)&hdr);
780
781 #ifdef DEBUG
782 printk ("(%x,%d,%d,%d) (%lx,%lx,%lx,%lx) %lx %lx\n",
783 hdr.magic, hdr.track, hdr.sect, hdr.ord,
784 *(ulong *)&hdr.labels[0], *(ulong *)&hdr.labels[4],
785 *(ulong *)&hdr.labels[8], *(ulong *)&hdr.labels[12],
786 hdr.hdrchk, hdr.datachk);
787 #endif
788
789 if (hdr.hdrchk != csum) {
790 printk(KERN_INFO "MFM_HEADER: %08lx,%08lx\n", hdr.hdrchk, csum);
791 return MFM_HEADER;
792 }
793
794 /* verify track */
795 if (hdr.track != unit[drive].track) {
796 printk(KERN_INFO "MFM_TRACK: %d, %d\n", hdr.track, unit[drive].track);
797 return MFM_TRACK;
798 }
799
800 raw = decode ((ulong *)(unit[drive].trackbuf + hdr.sect*512),
801 (ulong *)raw, 512);
802 csum = checksum((ulong *)(unit[drive].trackbuf + hdr.sect*512), 512);
803
804 if (hdr.datachk != csum) {
805 printk(KERN_INFO "MFM_DATA: (%x:%d:%d:%d) sc=%d %lx, %lx\n",
806 hdr.magic, hdr.track, hdr.sect, hdr.ord, scnt,
807 hdr.datachk, csum);
808 printk (KERN_INFO "data=(%lx,%lx,%lx,%lx)\n",
809 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[0],
810 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[1],
811 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[2],
812 ((ulong *)(unit[drive].trackbuf+hdr.sect*512))[3]);
813 return MFM_DATA;
814 }
815 }
816
817 return 0;
818 }
819
820 static void encode(unsigned long data, unsigned long *dest)
821 {
822 unsigned long data2;
823
824 data &= 0x55555555;
825 data2 = data ^ 0x55555555;
826 data |= ((data2 >> 1) | 0x80000000) & (data2 << 1);
827
828 if (*(dest - 1) & 0x00000001)
829 data &= 0x7FFFFFFF;
830
831 *dest = data;
832 }
833
834 static void encode_block(unsigned long *dest, unsigned long *src, int len)
835 {
836 int cnt, to_cnt = 0;
837 unsigned long data;
838
839 /* odd bits */
840 for (cnt = 0; cnt < len / 4; cnt++) {
841 data = src[cnt] >> 1;
842 encode(data, dest + to_cnt++);
843 }
844
845 /* even bits */
846 for (cnt = 0; cnt < len / 4; cnt++) {
847 data = src[cnt];
848 encode(data, dest + to_cnt++);
849 }
850 }
851
852 static unsigned long *putsec(int disk, unsigned long *raw, int cnt)
853 {
854 struct header hdr;
855 int i;
856
857 disk&=3;
858 *raw = (raw[-1]&1) ? 0x2AAAAAAA : 0xAAAAAAAA;
859 raw++;
860 *raw++ = 0x44894489;
861
862 hdr.magic = 0xFF;
863 hdr.track = unit[disk].track;
864 hdr.sect = cnt;
865 hdr.ord = unit[disk].dtype->sects * unit[disk].type->sect_mult - cnt;
866 for (i = 0; i < 16; i++)
867 hdr.labels[i] = 0;
868 hdr.hdrchk = checksum((ulong *)&hdr,
869 (char *)&hdr.hdrchk-(char *)&hdr);
870 hdr.datachk = checksum((ulong *)(unit[disk].trackbuf+cnt*512), 512);
871
872 encode_block(raw, (ulong *)&hdr.magic, 4);
873 raw += 2;
874 encode_block(raw, (ulong *)&hdr.labels, 16);
875 raw += 8;
876 encode_block(raw, (ulong *)&hdr.hdrchk, 4);
877 raw += 2;
878 encode_block(raw, (ulong *)&hdr.datachk, 4);
879 raw += 2;
880 encode_block(raw, (ulong *)(unit[disk].trackbuf+cnt*512), 512);
881 raw += 256;
882
883 return raw;
884 }
885
886 static void amiga_write(int disk)
887 {
888 unsigned int cnt;
889 unsigned long *ptr = (unsigned long *)raw_buf;
890
891 disk&=3;
892 /* gap space */
893 for (cnt = 0; cnt < 415 * unit[disk].type->sect_mult; cnt++)
894 *ptr++ = 0xaaaaaaaa;
895
896 /* sectors */
897 for (cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
898 ptr = putsec (disk, ptr, cnt);
899 *(ushort *)ptr = (ptr[-1]&1) ? 0x2AA8 : 0xAAA8;
900 }
901
902
903 struct dos_header {
904 unsigned char track, /* 0-80 */
905 side, /* 0-1 */
906 sec, /* 0-...*/
907 len_desc;/* 2 */
908 unsigned short crc; /* on 68000 we got an alignment problem,
909 but this compiler solves it by adding silently
910 adding a pad byte so data won't fit
911 and this took about 3h to discover.... */
912 unsigned char gap1[22]; /* for longword-alignedness (0x4e) */
913 };
914
915 /* crc routines are borrowed from the messydos-handler */
916
917 /* excerpt from the messydos-device
918 ; The CRC is computed not only over the actual data, but including
919 ; the SYNC mark (3 * $a1) and the 'ID/DATA - Address Mark' ($fe/$fb).
920 ; As we don't read or encode these fields into our buffers, we have to
921 ; preload the registers containing the CRC with the values they would have
922 ; after stepping over these fields.
923 ;
924 ; How CRCs "really" work:
925 ;
926 ; First, you should regard a bitstring as a series of coefficients of
927 ; polynomials. We calculate with these polynomials in modulo-2
928 ; arithmetic, in which both add and subtract are done the same as
929 ; exclusive-or. Now, we modify our data (a very long polynomial) in
930 ; such a way that it becomes divisible by the CCITT-standard 16-bit
931 ; 16 12 5
932 ; polynomial: x + x + x + 1, represented by $11021. The easiest
933 ; way to do this would be to multiply (using proper arithmetic) our
934 ; datablock with $11021. So we have:
935 ; data * $11021 =
936 ; data * ($10000 + $1021) =
937 ; data * $10000 + data * $1021
938 ; The left part of this is simple: Just add two 0 bytes. But then
939 ; the right part (data $1021) remains difficult and even could have
940 ; a carry into the left part. The solution is to use a modified
941 ; multiplication, which has a result that is not correct, but with
942 ; a difference of any multiple of $11021. We then only need to keep
943 ; the 16 least significant bits of the result.
944 ;
945 ; The following algorithm does this for us:
946 ;
947 ; unsigned char *data, c, crclo, crchi;
948 ; while (not done) {
949 ; c = *data++ + crchi;
950 ; crchi = (@ c) >> 8 + crclo;
951 ; crclo = @ c;
952 ; }
953 ;
954 ; Remember, + is done with EOR, the @ operator is in two tables (high
955 ; and low byte separately), which is calculated as
956 ;
957 ; $1021 * (c & $F0)
958 ; xor $1021 * (c & $0F)
959 ; xor $1021 * (c >> 4) (* is regular multiplication)
960 ;
961 ;
962 ; Anyway, the end result is the same as the remainder of the division of
963 ; the data by $11021. I am afraid I need to study theory a bit more...
964
965
966 my only works was to code this from manx to C....
967
968 */
969
970 static ushort dos_crc(void * data_a3, int data_d0, int data_d1, int data_d3)
971 {
972 static unsigned char CRCTable1[] = {
973 0x00,0x10,0x20,0x30,0x40,0x50,0x60,0x70,0x81,0x91,0xa1,0xb1,0xc1,0xd1,0xe1,0xf1,
974 0x12,0x02,0x32,0x22,0x52,0x42,0x72,0x62,0x93,0x83,0xb3,0xa3,0xd3,0xc3,0xf3,0xe3,
975 0x24,0x34,0x04,0x14,0x64,0x74,0x44,0x54,0xa5,0xb5,0x85,0x95,0xe5,0xf5,0xc5,0xd5,
976 0x36,0x26,0x16,0x06,0x76,0x66,0x56,0x46,0xb7,0xa7,0x97,0x87,0xf7,0xe7,0xd7,0xc7,
977 0x48,0x58,0x68,0x78,0x08,0x18,0x28,0x38,0xc9,0xd9,0xe9,0xf9,0x89,0x99,0xa9,0xb9,
978 0x5a,0x4a,0x7a,0x6a,0x1a,0x0a,0x3a,0x2a,0xdb,0xcb,0xfb,0xeb,0x9b,0x8b,0xbb,0xab,
979 0x6c,0x7c,0x4c,0x5c,0x2c,0x3c,0x0c,0x1c,0xed,0xfd,0xcd,0xdd,0xad,0xbd,0x8d,0x9d,
980 0x7e,0x6e,0x5e,0x4e,0x3e,0x2e,0x1e,0x0e,0xff,0xef,0xdf,0xcf,0xbf,0xaf,0x9f,0x8f,
981 0x91,0x81,0xb1,0xa1,0xd1,0xc1,0xf1,0xe1,0x10,0x00,0x30,0x20,0x50,0x40,0x70,0x60,
982 0x83,0x93,0xa3,0xb3,0xc3,0xd3,0xe3,0xf3,0x02,0x12,0x22,0x32,0x42,0x52,0x62,0x72,
983 0xb5,0xa5,0x95,0x85,0xf5,0xe5,0xd5,0xc5,0x34,0x24,0x14,0x04,0x74,0x64,0x54,0x44,
984 0xa7,0xb7,0x87,0x97,0xe7,0xf7,0xc7,0xd7,0x26,0x36,0x06,0x16,0x66,0x76,0x46,0x56,
985 0xd9,0xc9,0xf9,0xe9,0x99,0x89,0xb9,0xa9,0x58,0x48,0x78,0x68,0x18,0x08,0x38,0x28,
986 0xcb,0xdb,0xeb,0xfb,0x8b,0x9b,0xab,0xbb,0x4a,0x5a,0x6a,0x7a,0x0a,0x1a,0x2a,0x3a,
987 0xfd,0xed,0xdd,0xcd,0xbd,0xad,0x9d,0x8d,0x7c,0x6c,0x5c,0x4c,0x3c,0x2c,0x1c,0x0c,
988 0xef,0xff,0xcf,0xdf,0xaf,0xbf,0x8f,0x9f,0x6e,0x7e,0x4e,0x5e,0x2e,0x3e,0x0e,0x1e
989 };
990
991 static unsigned char CRCTable2[] = {
992 0x00,0x21,0x42,0x63,0x84,0xa5,0xc6,0xe7,0x08,0x29,0x4a,0x6b,0x8c,0xad,0xce,0xef,
993 0x31,0x10,0x73,0x52,0xb5,0x94,0xf7,0xd6,0x39,0x18,0x7b,0x5a,0xbd,0x9c,0xff,0xde,
994 0x62,0x43,0x20,0x01,0xe6,0xc7,0xa4,0x85,0x6a,0x4b,0x28,0x09,0xee,0xcf,0xac,0x8d,
995 0x53,0x72,0x11,0x30,0xd7,0xf6,0x95,0xb4,0x5b,0x7a,0x19,0x38,0xdf,0xfe,0x9d,0xbc,
996 0xc4,0xe5,0x86,0xa7,0x40,0x61,0x02,0x23,0xcc,0xed,0x8e,0xaf,0x48,0x69,0x0a,0x2b,
997 0xf5,0xd4,0xb7,0x96,0x71,0x50,0x33,0x12,0xfd,0xdc,0xbf,0x9e,0x79,0x58,0x3b,0x1a,
998 0xa6,0x87,0xe4,0xc5,0x22,0x03,0x60,0x41,0xae,0x8f,0xec,0xcd,0x2a,0x0b,0x68,0x49,
999 0x97,0xb6,0xd5,0xf4,0x13,0x32,0x51,0x70,0x9f,0xbe,0xdd,0xfc,0x1b,0x3a,0x59,0x78,
1000 0x88,0xa9,0xca,0xeb,0x0c,0x2d,0x4e,0x6f,0x80,0xa1,0xc2,0xe3,0x04,0x25,0x46,0x67,
1001 0xb9,0x98,0xfb,0xda,0x3d,0x1c,0x7f,0x5e,0xb1,0x90,0xf3,0xd2,0x35,0x14,0x77,0x56,
1002 0xea,0xcb,0xa8,0x89,0x6e,0x4f,0x2c,0x0d,0xe2,0xc3,0xa0,0x81,0x66,0x47,0x24,0x05,
1003 0xdb,0xfa,0x99,0xb8,0x5f,0x7e,0x1d,0x3c,0xd3,0xf2,0x91,0xb0,0x57,0x76,0x15,0x34,
1004 0x4c,0x6d,0x0e,0x2f,0xc8,0xe9,0x8a,0xab,0x44,0x65,0x06,0x27,0xc0,0xe1,0x82,0xa3,
1005 0x7d,0x5c,0x3f,0x1e,0xf9,0xd8,0xbb,0x9a,0x75,0x54,0x37,0x16,0xf1,0xd0,0xb3,0x92,
1006 0x2e,0x0f,0x6c,0x4d,0xaa,0x8b,0xe8,0xc9,0x26,0x07,0x64,0x45,0xa2,0x83,0xe0,0xc1,
1007 0x1f,0x3e,0x5d,0x7c,0x9b,0xba,0xd9,0xf8,0x17,0x36,0x55,0x74,0x93,0xb2,0xd1,0xf0
1008 };
1009
1010 /* look at the asm-code - what looks in C a bit strange is almost as good as handmade */
1011 register int i;
1012 register unsigned char *CRCT1, *CRCT2, *data, c, crch, crcl;
1013
1014 CRCT1=CRCTable1;
1015 CRCT2=CRCTable2;
1016 data=data_a3;
1017 crcl=data_d1;
1018 crch=data_d0;
1019 for (i=data_d3; i>=0; i--) {
1020 c = (*data++) ^ crch;
1021 crch = CRCT1[c] ^ crcl;
1022 crcl = CRCT2[c];
1023 }
1024 return (crch<<8)|crcl;
1025 }
1026
1027 static inline ushort dos_hdr_crc (struct dos_header *hdr)
1028 {
1029 return dos_crc(&(hdr->track), 0xb2, 0x30, 3); /* precomputed magic */
1030 }
1031
1032 static inline ushort dos_data_crc(unsigned char *data)
1033 {
1034 return dos_crc(data, 0xe2, 0x95 ,511); /* precomputed magic */
1035 }
1036
1037 static inline unsigned char dos_decode_byte(ushort word)
1038 {
1039 register ushort w2;
1040 register unsigned char byte;
1041 register unsigned char *dec = mfmdecode;
1042
1043 w2=word;
1044 w2>>=8;
1045 w2&=127;
1046 byte = dec[w2];
1047 byte <<= 4;
1048 w2 = word & 127;
1049 byte |= dec[w2];
1050 return byte;
1051 }
1052
1053 static unsigned long dos_decode(unsigned char *data, unsigned short *raw, int len)
1054 {
1055 int i;
1056
1057 for (i = 0; i < len; i++)
1058 *data++=dos_decode_byte(*raw++);
1059 return ((ulong)raw);
1060 }
1061
1062 #ifdef DEBUG
1063 static void dbg(unsigned long ptr)
1064 {
1065 printk("raw data @%08lx: %08lx, %08lx ,%08lx, %08lx\n", ptr,
1066 ((ulong *)ptr)[0], ((ulong *)ptr)[1],
1067 ((ulong *)ptr)[2], ((ulong *)ptr)[3]);
1068 }
1069 #endif
1070
1071 static int dos_read(int drive)
1072 {
1073 unsigned long end;
1074 unsigned long raw;
1075 int scnt;
1076 unsigned short crc,data_crc[2];
1077 struct dos_header hdr;
1078
1079 drive&=3;
1080 raw = (long) raw_buf;
1081 end = raw + unit[drive].type->read_size;
1082
1083 for (scnt=0; scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
1084 do { /* search for the right sync of each sec-hdr */
1085 if (!(raw = scan_sync (raw, end))) {
1086 printk(KERN_INFO "dos_read: no hdr sync on "
1087 "track %d, unit %d for sector %d\n",
1088 unit[drive].track,drive,scnt);
1089 return MFM_NOSYNC;
1090 }
1091 #ifdef DEBUG
1092 dbg(raw);
1093 #endif
1094 } while (*((ushort *)raw)!=0x5554); /* loop usually only once done */
1095 raw+=2; /* skip over headermark */
1096 raw = dos_decode((unsigned char *)&hdr,(ushort *) raw,8);
1097 crc = dos_hdr_crc(&hdr);
1098
1099 #ifdef DEBUG
1100 printk("(%3d,%d,%2d,%d) %x\n", hdr.track, hdr.side,
1101 hdr.sec, hdr.len_desc, hdr.crc);
1102 #endif
1103
1104 if (crc != hdr.crc) {
1105 printk(KERN_INFO "dos_read: MFM_HEADER %04x,%04x\n",
1106 hdr.crc, crc);
1107 return MFM_HEADER;
1108 }
1109 if (hdr.track != unit[drive].track/unit[drive].type->heads) {
1110 printk(KERN_INFO "dos_read: MFM_TRACK %d, %d\n",
1111 hdr.track,
1112 unit[drive].track/unit[drive].type->heads);
1113 return MFM_TRACK;
1114 }
1115
1116 if (hdr.side != unit[drive].track%unit[drive].type->heads) {
1117 printk(KERN_INFO "dos_read: MFM_SIDE %d, %d\n",
1118 hdr.side,
1119 unit[drive].track%unit[drive].type->heads);
1120 return MFM_TRACK;
1121 }
1122
1123 if (hdr.len_desc != 2) {
1124 printk(KERN_INFO "dos_read: unknown sector len "
1125 "descriptor %d\n", hdr.len_desc);
1126 return MFM_DATA;
1127 }
1128 #ifdef DEBUG
1129 printk("hdr accepted\n");
1130 #endif
1131 if (!(raw = scan_sync (raw, end))) {
1132 printk(KERN_INFO "dos_read: no data sync on track "
1133 "%d, unit %d for sector%d, disk sector %d\n",
1134 unit[drive].track, drive, scnt, hdr.sec);
1135 return MFM_NOSYNC;
1136 }
1137 #ifdef DEBUG
1138 dbg(raw);
1139 #endif
1140
1141 if (*((ushort *)raw)!=0x5545) {
1142 printk(KERN_INFO "dos_read: no data mark after "
1143 "sync (%d,%d,%d,%d) sc=%d\n",
1144 hdr.track,hdr.side,hdr.sec,hdr.len_desc,scnt);
1145 return MFM_NOSYNC;
1146 }
1147
1148 raw+=2; /* skip data mark (included in checksum) */
1149 raw = dos_decode((unsigned char *)(unit[drive].trackbuf + (hdr.sec - 1) * 512), (ushort *) raw, 512);
1150 raw = dos_decode((unsigned char *)data_crc,(ushort *) raw,4);
1151 crc = dos_data_crc(unit[drive].trackbuf + (hdr.sec - 1) * 512);
1152
1153 if (crc != data_crc[0]) {
1154 printk(KERN_INFO "dos_read: MFM_DATA (%d,%d,%d,%d) "
1155 "sc=%d, %x %x\n", hdr.track, hdr.side,
1156 hdr.sec, hdr.len_desc, scnt,data_crc[0], crc);
1157 printk(KERN_INFO "data=(%lx,%lx,%lx,%lx,...)\n",
1158 ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[0],
1159 ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[1],
1160 ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[2],
1161 ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[3]);
1162 return MFM_DATA;
1163 }
1164 }
1165 return 0;
1166 }
1167
1168 static inline ushort dos_encode_byte(unsigned char byte)
1169 {
1170 register unsigned char *enc, b2, b1;
1171 register ushort word;
1172
1173 enc=mfmencode;
1174 b1=byte;
1175 b2=b1>>4;
1176 b1&=15;
1177 word=enc[b2] <<8 | enc [b1];
1178 return (word|((word&(256|64)) ? 0: 128));
1179 }
1180
1181 static void dos_encode_block(ushort *dest, unsigned char *src, int len)
1182 {
1183 int i;
1184
1185 for (i = 0; i < len; i++) {
1186 *dest=dos_encode_byte(*src++);
1187 *dest|=((dest[-1]&1)||(*dest&0x4000))? 0: 0x8000;
1188 dest++;
1189 }
1190 }
1191
1192 static unsigned long *ms_putsec(int drive, unsigned long *raw, int cnt)
1193 {
1194 static struct dos_header hdr={0,0,0,2,0,
1195 {78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78}};
1196 int i;
1197 static ushort crc[2]={0,0x4e4e};
1198
1199 drive&=3;
1200 /* id gap 1 */
1201 /* the MFM word before is always 9254 */
1202 for(i=0;i<6;i++)
1203 *raw++=0xaaaaaaaa;
1204 /* 3 sync + 1 headermark */
1205 *raw++=0x44894489;
1206 *raw++=0x44895554;
1207
1208 /* fill in the variable parts of the header */
1209 hdr.track=unit[drive].track/unit[drive].type->heads;
1210 hdr.side=unit[drive].track%unit[drive].type->heads;
1211 hdr.sec=cnt+1;
1212 hdr.crc=dos_hdr_crc(&hdr);
1213
1214 /* header (without "magic") and id gap 2*/
1215 dos_encode_block((ushort *)raw,(unsigned char *) &hdr.track,28);
1216 raw+=14;
1217
1218 /*id gap 3 */
1219 for(i=0;i<6;i++)
1220 *raw++=0xaaaaaaaa;
1221
1222 /* 3 syncs and 1 datamark */
1223 *raw++=0x44894489;
1224 *raw++=0x44895545;
1225
1226 /* data */
1227 dos_encode_block((ushort *)raw,
1228 (unsigned char *)unit[drive].trackbuf+cnt*512,512);
1229 raw+=256;
1230
1231 /*data crc + jd's special gap (long words :-/) */
1232 crc[0]=dos_data_crc(unit[drive].trackbuf+cnt*512);
1233 dos_encode_block((ushort *) raw,(unsigned char *)crc,4);
1234 raw+=2;
1235
1236 /* data gap */
1237 for(i=0;i<38;i++)
1238 *raw++=0x92549254;
1239
1240 return raw; /* wrote 652 MFM words */
1241 }
1242
1243 static void dos_write(int disk)
1244 {
1245 int cnt;
1246 unsigned long raw = (unsigned long) raw_buf;
1247 unsigned long *ptr=(unsigned long *)raw;
1248
1249 disk&=3;
1250 /* really gap4 + indexgap , but we write it first and round it up */
1251 for (cnt=0;cnt<425;cnt++)
1252 *ptr++=0x92549254;
1253
1254 /* the following is just guessed */
1255 if (unit[disk].type->sect_mult==2) /* check for HD-Disks */
1256 for(cnt=0;cnt<473;cnt++)
1257 *ptr++=0x92549254;
1258
1259 /* now the index marks...*/
1260 for (cnt=0;cnt<20;cnt++)
1261 *ptr++=0x92549254;
1262 for (cnt=0;cnt<6;cnt++)
1263 *ptr++=0xaaaaaaaa;
1264 *ptr++=0x52245224;
1265 *ptr++=0x52245552;
1266 for (cnt=0;cnt<20;cnt++)
1267 *ptr++=0x92549254;
1268
1269 /* sectors */
1270 for(cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
1271 ptr=ms_putsec(disk,ptr,cnt);
1272
1273 *(ushort *)ptr = 0xaaa8; /* MFM word before is always 0x9254 */
1274 }
1275
1276 /*
1277 * Here comes the high level stuff (i.e. the filesystem interface)
1278 * and helper functions.
1279 * Normally this should be the only part that has to be adapted to
1280 * different kernel versions.
1281 */
1282
1283 /* FIXME: this assumes the drive is still spinning -
1284 * which is only true if we complete writing a track within three seconds
1285 */
1286 static void flush_track_callback(unsigned long nr)
1287 {
1288 nr&=3;
1289 writefromint = 1;
1290 if (!try_fdc(nr)) {
1291 /* we might block in an interrupt, so try again later */
1292 flush_track_timer[nr].expires = jiffies + 1;
1293 add_timer(flush_track_timer + nr);
1294 return;
1295 }
1296 get_fdc(nr);
1297 (*unit[nr].dtype->write_fkt)(nr);
1298 if (!raw_write(nr)) {
1299 printk (KERN_NOTICE "floppy disk write protected\n");
1300 writefromint = 0;
1301 writepending = 0;
1302 }
1303 rel_fdc();
1304 }
1305
1306 static int non_int_flush_track (unsigned long nr)
1307 {
1308 unsigned long flags;
1309
1310 nr&=3;
1311 writefromint = 0;
1312 del_timer(&post_write_timer);
1313 get_fdc(nr);
1314 if (!fd_motor_on(nr)) {
1315 writepending = 0;
1316 rel_fdc();
1317 return 0;
1318 }
1319 save_flags(flags);
1320 cli();
1321 if (writepending != 2) {
1322 restore_flags(flags);
1323 (*unit[nr].dtype->write_fkt)(nr);
1324 if (!raw_write(nr)) {
1325 printk (KERN_NOTICE "floppy disk write protected "
1326 "in write!\n");
1327 writepending = 0;
1328 return 0;
1329 }
1330 while (block_flag == 2)
1331 sleep_on (&wait_fd_block);
1332 }
1333 else {
1334 restore_flags(flags);
1335 ms_delay(2); /* 2 ms post_write delay */
1336 post_write(nr);
1337 }
1338 rel_fdc();
1339 return 1;
1340 }
1341
1342 static int get_track(int drive, int track)
1343 {
1344 int error, errcnt;
1345
1346 drive&=3;
1347 if (unit[drive].track == track)
1348 return 0;
1349 get_fdc(drive);
1350 if (!fd_motor_on(drive)) {
1351 rel_fdc();
1352 return -1;
1353 }
1354
1355 if (unit[drive].dirty == 1) {
1356 del_timer (flush_track_timer + drive);
1357 non_int_flush_track (drive);
1358 }
1359 errcnt = 0;
1360 while (errcnt < MAX_ERRORS) {
1361 if (!fd_seek(drive, track))
1362 return -1;
1363 raw_read(drive);
1364 error = (*unit[drive].dtype->read_fkt)(drive);
1365 if (error == 0) {
1366 rel_fdc();
1367 return 0;
1368 }
1369 /* Read Error Handling: recalibrate and try again */
1370 unit[drive].track = -1;
1371 errcnt++;
1372 }
1373 rel_fdc();
1374 return -1;
1375 }
1376
1377 static void redo_fd_request(void)
1378 {
1379 unsigned int cnt, block, track, sector;
1380 int device, drive;
1381 struct amiga_floppy_struct *floppy;
1382 char *data;
1383 unsigned long flags;
1384
1385 if (!QUEUE_EMPTY && CURRENT->rq_status == RQ_INACTIVE){
1386 return;
1387 }
1388
1389 repeat:
1390 if (QUEUE_EMPTY) {
1391 /* Nothing left to do */
1392 return;
1393 }
1394
1395 if (MAJOR(CURRENT->rq_dev) != MAJOR_NR)
1396 panic(DEVICE_NAME ": request list destroyed");
1397
1398 if (CURRENT->bh && !buffer_locked(CURRENT->bh))
1399 panic(DEVICE_NAME ": block not locked");
1400
1401 device = MINOR(CURRENT_DEVICE);
1402 if (device < 8) {
1403 /* manual selection */
1404 drive = device & 3;
1405 floppy = unit + drive;
1406 } else {
1407 /* Auto-detection */
1408 #ifdef DEBUG
1409 printk("redo_fd_request: can't handle auto detect\n");
1410 printk("redo_fd_request: default to normal\n");
1411 #endif
1412 drive = device & 3;
1413 floppy = unit + drive;
1414 }
1415
1416 /* Here someone could investigate to be more efficient */
1417 for (cnt = 0; cnt < CURRENT->current_nr_sectors; cnt++) {
1418 #ifdef DEBUG
1419 printk("fd: sector %ld + %d requested for %s\n",
1420 CURRENT->sector,cnt,
1421 (CURRENT->cmd==READ)?"read":"write");
1422 #endif
1423 block = CURRENT->sector + cnt;
1424 if ((int)block > floppy->blocks) {
1425 end_request(0);
1426 goto repeat;
1427 }
1428
1429 track = block / (floppy->dtype->sects * floppy->type->sect_mult);
1430 sector = block % (floppy->dtype->sects * floppy->type->sect_mult);
1431 data = CURRENT->buffer + 512 * cnt;
1432 #ifdef DEBUG
1433 printk("access to track %d, sector %d, with buffer at "
1434 "0x%08lx\n", track, sector, data);
1435 #endif
1436
1437 if ((CURRENT->cmd != READ) && (CURRENT->cmd != WRITE)) {
1438 printk(KERN_WARNING "do_fd_request: unknown command\n");
1439 end_request(0);
1440 goto repeat;
1441 }
1442 if (get_track(drive, track) == -1) {
1443 end_request(0);
1444 goto repeat;
1445 }
1446
1447 switch (CURRENT->cmd) {
1448 case READ:
1449 memcpy(data, unit[drive].trackbuf + sector * 512, 512);
1450 break;
1451
1452 case WRITE:
1453 memcpy(unit[drive].trackbuf + sector * 512, data, 512);
1454
1455 /* keep the drive spinning while writes are scheduled */
1456 if (!fd_motor_on(drive)) {
1457 end_request(0);
1458 goto repeat;
1459 }
1460 /*
1461 * setup a callback to write the track buffer
1462 * after a short (1 tick) delay.
1463 */
1464 save_flags (flags);
1465 cli();
1466
1467 unit[drive].dirty = 1;
1468 /* reset the timer */
1469 del_timer (flush_track_timer + drive);
1470
1471 flush_track_timer[drive].expires = jiffies + 1;
1472 add_timer (flush_track_timer + drive);
1473 restore_flags (flags);
1474 break;
1475 }
1476 }
1477 CURRENT->nr_sectors -= CURRENT->current_nr_sectors;
1478 CURRENT->sector += CURRENT->current_nr_sectors;
1479
1480 end_request(1);
1481 goto repeat;
1482 }
1483
1484 static void do_fd_request(request_queue_t * q)
1485 {
1486 redo_fd_request();
1487 }
1488
1489 static int fd_ioctl(struct inode *inode, struct file *filp,
1490 unsigned int cmd, unsigned long param)
1491 {
1492 int drive = inode->i_rdev & 3;
1493 static struct floppy_struct getprm;
1494 struct super_block * sb;
1495
1496 switch(cmd){
1497 case HDIO_GETGEO:
1498 {
1499 struct hd_geometry loc;
1500 loc.heads = unit[drive].type->heads;
1501 loc.sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;
1502 loc.cylinders = unit[drive].type->tracks;
1503 loc.start = 0;
1504 if (copy_to_user((void *)param, (void *)&loc,
1505 sizeof(struct hd_geometry)))
1506 return -EFAULT;
1507 break;
1508 }
1509 case FDFMTBEG:
1510 get_fdc(drive);
1511 if (fd_ref[drive] > 1) {
1512 rel_fdc();
1513 return -EBUSY;
1514 }
1515 fsync_dev(inode->i_rdev);
1516 if (fd_motor_on(drive) == 0) {
1517 rel_fdc();
1518 return -ENODEV;
1519 }
1520 if (fd_calibrate(drive) == 0) {
1521 rel_fdc();
1522 return -ENXIO;
1523 }
1524 floppy_off(drive);
1525 rel_fdc();
1526 break;
1527 case FDFMTTRK:
1528 if (param < unit[drive].type->tracks * unit[drive].type->heads)
1529 {
1530 get_fdc(drive);
1531 if (fd_seek(drive,param) != 0){
1532 memset(unit[drive].trackbuf, FD_FILL_BYTE,
1533 unit[drive].dtype->sects * unit[drive].type->sect_mult * 512);
1534 non_int_flush_track(drive);
1535 }
1536 floppy_off(drive);
1537 rel_fdc();
1538 }
1539 else
1540 return -EINVAL;
1541 break;
1542 case FDFMTEND:
1543 floppy_off(drive);
1544 invalidate_device(inode->i_rdev, 0);
1545 break;
1546 case FDGETPRM:
1547 memset((void *)&getprm, 0, sizeof (getprm));
1548 getprm.track=unit[drive].type->tracks;
1549 getprm.head=unit[drive].type->heads;
1550 getprm.sect=unit[drive].dtype->sects * unit[drive].type->sect_mult;
1551 getprm.size=unit[drive].blocks;
1552 if (copy_to_user((void *)param,
1553 (void *)&getprm,
1554 sizeof(struct floppy_struct)))
1555 return -EFAULT;
1556 break;
1557 case BLKGETSIZE:
1558 return put_user(unit[drive].blocks,(long *)param);
1559 break;
1560 case BLKGETSIZE64:
1561 return put_user((u64)unit[drive].blocks << 9, (u64 *)param);
1562 break;
1563 case FDSETPRM:
1564 case FDDEFPRM:
1565 return -EINVAL;
1566 case FDFLUSH: /* unconditionally, even if not needed */
1567 del_timer (flush_track_timer + drive);
1568 non_int_flush_track(drive);
1569 break;
1570 #ifdef RAW_IOCTL
1571 case IOCTL_RAW_TRACK:
1572 if (copy_to_user((void *)param, raw_buf,
1573 unit[drive].type->read_size))
1574 return -EFAULT;
1575 else
1576 return unit[drive].type->read_size;
1577 #endif
1578 default:
1579 printk(KERN_DEBUG "fd_ioctl: unknown cmd %d for drive %d.",
1580 cmd, drive);
1581 return -ENOSYS;
1582 }
1583 return 0;
1584 }
1585
1586 static void fd_probe(int dev)
1587 {
1588 unsigned long code;
1589 int type;
1590 int drive;
1591
1592 drive = dev & 3;
1593 code = fd_get_drive_id(drive);
1594
1595 /* get drive type */
1596 for (type = 0; type < num_dr_types; type++)
1597 if (drive_types[type].code == code)
1598 break;
1599
1600 if (type >= num_dr_types) {
1601 printk(KERN_WARNING "fd_probe: unsupported drive type "
1602 "%08lx found\n", code);
1603 unit[drive].type = &drive_types[num_dr_types-1]; /* FD_NODRIVE */
1604 return;
1605 }
1606
1607 unit[drive].type = drive_types + type;
1608 unit[drive].track = -1;
1609
1610 unit[drive].disk = -1;
1611 unit[drive].motor = 0;
1612 unit[drive].busy = 0;
1613 unit[drive].status = -1;
1614 }
1615
1616 /*
1617 * floppy_open check for aliasing (/dev/fd0 can be the same as
1618 * /dev/PS0 etc), and disallows simultaneous access to the same
1619 * drive with different device numbers.
1620 */
1621 static int floppy_open(struct inode *inode, struct file *filp)
1622 {
1623 int drive;
1624 int old_dev;
1625 int system;
1626 unsigned long flags;
1627
1628 drive = MINOR(inode->i_rdev) & 3;
1629 old_dev = fd_device[drive];
1630
1631 if (fd_ref[drive])
1632 if (old_dev != inode->i_rdev)
1633 return -EBUSY;
1634
1635 if (unit[drive].type->code == FD_NODRIVE)
1636 return -ENODEV;
1637
1638 if (filp && filp->f_mode & 3) {
1639 check_disk_change(inode->i_rdev);
1640 if (filp->f_mode & 2 ) {
1641 int wrprot;
1642
1643 get_fdc(drive);
1644 fd_select (drive);
1645 wrprot = !(ciaa.pra & DSKPROT);
1646 fd_deselect (drive);
1647 rel_fdc();
1648
1649 if (wrprot)
1650 return -EROFS;
1651 }
1652 }
1653
1654 save_flags(flags);
1655 cli();
1656 fd_ref[drive]++;
1657 fd_device[drive] = inode->i_rdev;
1658 #ifdef MODULE
1659 if (unit[drive].motor == 0)
1660 MOD_INC_USE_COUNT;
1661 #endif
1662 restore_flags(flags);
1663
1664 if (old_dev && old_dev != inode->i_rdev)
1665 invalidate_buffers(old_dev);
1666
1667 system=(inode->i_rdev & 4)>>2;
1668 unit[drive].dtype=&data_types[system];
1669 unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
1670 data_types[system].sects*unit[drive].type->sect_mult;
1671 floppy_sizes[MINOR(inode->i_rdev)] = unit[drive].blocks >> 1;
1672
1673 printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
1674 unit[drive].type->name, data_types[system].name);
1675
1676 return 0;
1677 }
1678
1679 static int floppy_release(struct inode * inode, struct file * filp)
1680 {
1681 #ifdef DEBUG
1682 struct super_block * sb;
1683 #endif
1684 int drive = MINOR(inode->i_rdev) & 3;
1685
1686 if (unit[drive].dirty == 1) {
1687 del_timer (flush_track_timer + drive);
1688 non_int_flush_track (drive);
1689 }
1690
1691 if (!fd_ref[drive]--) {
1692 printk(KERN_CRIT "floppy_release with fd_ref == 0");
1693 fd_ref[drive] = 0;
1694 }
1695 #ifdef MODULE
1696 /* the mod_use counter is handled this way */
1697 floppy_off (drive | 0x40000000);
1698 #endif
1699 return 0;
1700 }
1701
1702 /*
1703 * floppy-change is never called from an interrupt, so we can relax a bit
1704 * here, sleep etc. Note that floppy-on tries to set current_DOR to point
1705 * to the desired drive, but it will probably not survive the sleep if
1706 * several floppies are used at the same time: thus the loop.
1707 */
1708 static int amiga_floppy_change(kdev_t dev)
1709 {
1710 int drive = MINOR(dev) & 3;
1711 int changed;
1712 static int first_time = 1;
1713
1714 if (MAJOR(dev) != MAJOR_NR) {
1715 printk(KERN_CRIT "floppy_change: not a floppy\n");
1716 return 0;
1717 }
1718
1719 if (first_time)
1720 changed = first_time--;
1721 else {
1722 get_fdc(drive);
1723 fd_select (drive);
1724 changed = !(ciaa.pra & DSKCHANGE);
1725 fd_deselect (drive);
1726 rel_fdc();
1727 }
1728
1729 if (changed) {
1730 fd_probe(drive);
1731 unit[drive].track = -1;
1732 unit[drive].dirty = 0;
1733 writepending = 0; /* if this was true before, too bad! */
1734 writefromint = 0;
1735 return 1;
1736 }
1737 return 0;
1738 }
1739
1740 static struct block_device_operations floppy_fops = {
1741 open: floppy_open,
1742 release: floppy_release,
1743 ioctl: fd_ioctl,
1744 check_media_change: amiga_floppy_change,
1745 };
1746
1747 void __init amiga_floppy_setup (char *str, int *ints)
1748 {
1749 printk (KERN_INFO "amiflop: Setting default df0 to %x\n", ints[1]);
1750 fd_def_df0 = ints[1];
1751 }
1752
1753 static int __init fd_probe_drives(void)
1754 {
1755 int drive,drives,nomem;
1756
1757 printk(KERN_INFO "FD: probing units\n" KERN_INFO "found ");
1758 drives=0;
1759 nomem=0;
1760 for(drive=0;drive<FD_MAX_UNITS;drive++) {
1761 fd_probe(drive);
1762 if (unit[drive].type->code != FD_NODRIVE) {
1763 drives++;
1764 if ((unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL)) == NULL) {
1765 printk("no mem for ");
1766 unit[drive].type = &drive_types[num_dr_types - 1]; /* FD_NODRIVE */
1767 drives--;
1768 nomem = 1;
1769 }
1770 printk("fd%d ",drive);
1771 }
1772 }
1773 if ((drives > 0) || (nomem == 0)) {
1774 if (drives == 0)
1775 printk("no drives");
1776 printk("\n");
1777 return drives;
1778 }
1779 printk("\n");
1780 return -ENOMEM;
1781 }
1782
1783 int __init amiga_floppy_init(void)
1784 {
1785 int i;
1786
1787 if (!AMIGAHW_PRESENT(AMI_FLOPPY))
1788 return -ENXIO;
1789
1790 if (register_blkdev(MAJOR_NR,"fd",&floppy_fops)) {
1791 printk("fd: Unable to get major %d for floppy\n",MAJOR_NR);
1792 return -EBUSY;
1793 }
1794 /*
1795 * We request DSKPTR, DSKLEN and DSKDATA only, because the other
1796 * floppy registers are too spreaded over the custom register space
1797 */
1798 if (!request_mem_region(CUSTOM_PHYSADDR+0x20, 8, "amiflop [Paula]")) {
1799 printk("fd: cannot get floppy registers\n");
1800 unregister_blkdev(MAJOR_NR,"fd");
1801 return -EBUSY;
1802 }
1803 if ((raw_buf = (char *)amiga_chip_alloc (RAW_BUF_SIZE, "Floppy")) ==
1804 NULL) {
1805 printk("fd: cannot get chip mem buffer\n");
1806 release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
1807 unregister_blkdev(MAJOR_NR,"fd");
1808 return -ENOMEM;
1809 }
1810 if (request_irq(IRQ_AMIGA_DSKBLK, fd_block_done, 0, "floppy_dma", NULL)) {
1811 printk("fd: cannot get irq for dma\n");
1812 amiga_chip_free(raw_buf);
1813 release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
1814 unregister_blkdev(MAJOR_NR,"fd");
1815 return -EBUSY;
1816 }
1817 if (request_irq(IRQ_AMIGA_CIAA_TB, ms_isr, 0, "floppy_timer", NULL)) {
1818 printk("fd: cannot get irq for timer\n");
1819 free_irq(IRQ_AMIGA_DSKBLK, NULL);
1820 amiga_chip_free(raw_buf);
1821 release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
1822 unregister_blkdev(MAJOR_NR,"fd");
1823 return -EBUSY;
1824 }
1825 if (fd_probe_drives() < 1) { /* No usable drives */
1826 free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1827 free_irq(IRQ_AMIGA_DSKBLK, NULL);
1828 amiga_chip_free(raw_buf);
1829 release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
1830 unregister_blkdev(MAJOR_NR,"fd");
1831 return -ENXIO;
1832 }
1833
1834 /* initialize variables */
1835 init_timer(&motor_on_timer);
1836 motor_on_timer.expires = 0;
1837 motor_on_timer.data = 0;
1838 motor_on_timer.function = motor_on_callback;
1839 for (i = 0; i < FD_MAX_UNITS; i++) {
1840 init_timer(&motor_off_timer[i]);
1841 motor_off_timer[i].expires = 0;
1842 motor_off_timer[i].data = i|0x80000000;
1843 motor_off_timer[i].function = fd_motor_off;
1844 init_timer(&flush_track_timer[i]);
1845 flush_track_timer[i].expires = 0;
1846 flush_track_timer[i].data = i;
1847 flush_track_timer[i].function = flush_track_callback;
1848
1849 unit[i].track = -1;
1850 }
1851
1852 init_timer(&post_write_timer);
1853 post_write_timer.expires = 0;
1854 post_write_timer.data = 0;
1855 post_write_timer.function = post_write;
1856
1857 blk_init_queue(BLK_DEFAULT_QUEUE(MAJOR_NR), DEVICE_REQUEST);
1858 blksize_size[MAJOR_NR] = floppy_blocksizes;
1859 blk_size[MAJOR_NR] = floppy_sizes;
1860
1861 for (i = 0; i < 128; i++)
1862 mfmdecode[i]=255;
1863 for (i = 0; i < 16; i++)
1864 mfmdecode[mfmencode[i]]=i;
1865
1866 /* make sure that disk DMA is enabled */
1867 custom.dmacon = DMAF_SETCLR | DMAF_DISK;
1868
1869 /* init ms timer */
1870 ciaa.crb = 8; /* one-shot, stop */
1871
1872 (void)do_floppy; /* avoid warning about unused variable */
1873 return 0;
1874 }
1875
1876 #ifdef MODULE
1877 #include <linux/version.h>
1878
1879 int init_module(void)
1880 {
1881 if (!MACH_IS_AMIGA)
1882 return -ENXIO;
1883 return amiga_floppy_init();
1884 }
1885
1886 void cleanup_module(void)
1887 {
1888 int i;
1889
1890 for( i = 0; i < FD_MAX_UNITS; i++)
1891 if (unit[i].type->code != FD_NODRIVE)
1892 kfree(unit[i].trackbuf);
1893 free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1894 free_irq(IRQ_AMIGA_DSKBLK, NULL);
1895 custom.dmacon = DMAF_DISK; /* disable DMA */
1896 amiga_chip_free(raw_buf);
1897 blk_size[MAJOR_NR] = NULL;
1898 blksize_size[MAJOR_NR] = NULL;
1899 blk_cleanup_queue(BLK_DEFAULT_QUEUE(MAJOR_NR));
1900 release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
1901 unregister_blkdev(MAJOR_NR, "fd");
1902 }
1903 #endif
1904