1 // SPDX-License-Identifier: GPL-2.0-only
6  *  Portions of this driver are based on code contributed by Brad Pepers
9  *  - now no bugs(?) any more for both HD & DD
10  *  - added support for 40 Track 5.25" drives, 80-track hopefully behaves
11  *    like 3.5" dd (no way to test - are there any 5.25" drives out there
13  *  - wrote formatting routine (maybe dirty, but works)
15  *  june/july 1995 added ms-dos support by Joerg Dorchain
17  *  - currently only 9 and 18 sector disks
19  *  - fixed a bug with the internal trackbuffer when using multiple 
21  *  - made formatting a bit safer
22  *  - added command line and machine based default for "silent" df0
25  *  - works but I think it's inefficient. (look in redo_fd_request)
29  *  - usage ioctl(d, RAW_TRACK, ptr); the raw track buffer (MFM-encoded data
31  *    done - 30K is currently sufficient). return the actual size of the
33  *  - replaced udelays() by a timer (CIAA timer B) for the waits 
37  *  - both got broken the first time I tampered with the driver :-(
38  *  - still not safe, but better than before
41  *  - Minor changes to accept the kdev_t.
42  *  - Replaced some more udelays with ms_delays. Udelay is just a loop,
44  *    processor :-(
45  *  - The driver could use a major cleanup because of the new
51  * - Fixed Bug accessing multiple disks
52  * - some code cleanup
53  * - added trackbuffer for each drive to speed things up
54  * - fixed some race conditions (who finds the next may send it to me ;-)
67 #include <linux/blk-mq.h>
101 #define DSKMOTOR    (0x1<<7)        /* motor on when low */
118 /* bits 7-0 are data */
193 	int track;			/* current track (-1 == unknown) */
199 	int disk;			/* disk in drive (-1 == unknown) */
200 	int motor;			/* true when motor is at speed */  member
212 #define FD_ERROR	-1	/* general error (seek, read, write, etc) */
216 #define FD_NOTREADY	4	/* unit is not ready (motor not on/no disk) */
227 #define FD_DD_3 	0xffffffff  /* double-density 3.5" (880K) drive */
228 #define FD_HD_3 	0x55555555  /* high-density 3.5" (1760K) drive */
229 #define FD_DD_5 	0xaaaaaaaa  /* double-density 5.25" (440K) drive */
235 MODULE_DESCRIPTION("Amiga floppy driver");
261 	{ "MS-Dos", 9, dos_read, dos_write}
276 static volatile int fdc_busy = -1;
282 static volatile int selected = -1;	/* currently selected drive */
300 /* MS-Dos MFM Coding tables (should go quick and easy) */
313  * max X times - some types of errors increase the errorcount by 2 or
347 		ticks = MS_TICKS*ms-1;  in ms_delay()
350 		ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */  in ms_delay()
387 	fdc_nested--;  in rel_fdc()
389 		fdc_busy = -1;  in rel_fdc()
409 	if (unit[drive].motor == 1)  in fd_select()
435 	selected = -1;  in fd_deselect()
448 	if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {  in motor_on_callback()
462 	if (!unit[nr].motor) {  in fd_motor_on()
463 		unit[nr].motor = 1;  in fd_motor_on()
475 		on_attempts = -1;  in fd_motor_on()
477 		printk (KERN_ERR "motor_on failed, turning motor off\n");  in fd_motor_on()
481 …printk (KERN_WARNING "DSKRDY not set after 1.5 seconds - assuming drive is spinning notwithstandin…  in fd_motor_on()
490 	unsigned long drive = ((unsigned long)timer -  in fd_motor_off()
497 		timer->expires = jiffies + 1;  in fd_motor_off()
501 	unit[drive].motor = 0;  in fd_motor_off()
529 	for (n = unit[drive].type->tracks/2; n != 0; --n) {  in fd_calibrate()
537 		ms_delay(unit[drive].type->step_delay);  in fd_calibrate()
539 	ms_delay (unit[drive].type->settle_time);  in fd_calibrate()
541 	n = unit[drive].type->tracks + 20;  in fd_calibrate()
548 		ms_delay(unit[drive].type->step_delay + 1);  in fd_calibrate()
551 		if (--n == 0) {  in fd_calibrate()
552 			printk (KERN_ERR "fd%d: calibrate failed, turning motor off\n", drive);  in fd_calibrate()
554 			unit[drive].track = -1;  in fd_calibrate()
560 	ms_delay(unit[drive].type->settle_time);  in fd_calibrate()
591 	cnt = unit[drive].track/2 - track/2;  in fd_seek()
597 		cnt = - cnt;  in fd_seek()
602 		ms_delay (unit[drive].type->side_time);  in fd_seek()
615 		ms_delay (unit[drive].type->step_delay);  in fd_seek()
616 	} while (--cnt != 0);  in fd_seek()
617 	ms_delay (unit[drive].type->settle_time);  in fd_seek()
652 		id |= (ciaa.pra & DSKRDY) ? 0 : 1;	/* cia regs are low-active! */  in fd_get_drive_id()
706 	custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;  in raw_read()
707 	custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;  in raw_read()
734 	if ((ulong)unit[drive].track >= unit[drive].type->precomp2)  in raw_write()
736 	else if ((ulong)unit[drive].track >= unit[drive].type->precomp1)  in raw_write()
742 	custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;  in raw_write()
743 	custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;  in raw_write()
777  * (Add other formats here ;-))
799 	while (len-- > 0)  in checksum()
821 	} while (--len != 0);  in decode()
846 	end = raw + unit[drive].type->read_size;  in amiga_read()
848 	for (scnt = 0;scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {  in amiga_read()
859 				(char *)&hdr.hdrchk-(char *)&hdr);  in amiga_read()
908 	if (*(dest - 1) & 0x00000001)  in encode()
938 	*raw = (raw[-1]&1) ? 0x2AAAAAAA : 0xAAAAAAAA;  in putsec()
945 	hdr.ord = unit[disk].dtype->sects * unit[disk].type->sect_mult - cnt;  in putsec()
949 			      (char *)&hdr.hdrchk-(char *)&hdr);  in putsec()
973 	for (cnt = 0; cnt < 415 * unit[disk].type->sect_mult; cnt++)  in amiga_write()
977 	for (cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)  in amiga_write()
979 	*(ushort *)ptr = (ptr[-1]&1) ? 0x2AA8 : 0xAAA8;  in amiga_write()
984 	unsigned char track,   /* 0-80 */
985 		side,    /* 0-1 */
986 		sec,     /* 0-...*/
992 	unsigned char gap1[22];     /* for longword-alignedness (0x4e) */
995 /* crc routines are borrowed from the messydos-handler  */
997 /* excerpt from the messydos-device           
999 ; the SYNC mark (3 * $a1) and the 'ID/DATA - Address Mark' ($fe/$fb).
1007 ; polynomials. We calculate with these polynomials in modulo-2
1009 ; exclusive-or. Now, we modify our data (a very long polynomial) in
1010 ; such a way that it becomes divisible by the CCITT-standard 16-bit
1090 /* look at the asm-code - what looks in C a bit strange is almost as good as handmade */  in dos_crc()
1099 	for (i=data_d3; i>=0; i--) {  in dos_crc()
1109 	return dos_crc(&(hdr->track), 0xb2, 0x30, 3); /* precomputed magic */  in dos_hdr_crc()
1161 	end = raw + unit[drive].type->read_size;  in dos_read()
1163 	for (scnt=0; scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {  in dos_read()
1164 		do { /* search for the right sync of each sec-hdr */  in dos_read()
1189 		if (hdr.track != unit[drive].track/unit[drive].type->heads) {  in dos_read()
1192 			       unit[drive].track/unit[drive].type->heads);  in dos_read()
1196 		if (hdr.side != unit[drive].track%unit[drive].type->heads) {  in dos_read()
1199 			       unit[drive].track%unit[drive].type->heads);  in dos_read()
1229 …raw = dos_decode((unsigned char *)(unit[drive].trackbuf + (hdr.sec - 1) * 512), (ushort *) raw, 51…  in dos_read()
1231 		crc = dos_data_crc(unit[drive].trackbuf + (hdr.sec - 1) * 512);  in dos_read()
1238 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[0],  in dos_read()
1239 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[1],  in dos_read()
1240 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[2],  in dos_read()
1241 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[3]);  in dos_read()
1267 		*dest|=((dest[-1]&1)||(*dest&0x4000))? 0: 0x8000;  in dos_encode_block()
1289 	hdr.track=unit[drive].track/unit[drive].type->heads;  in ms_putsec()
1290 	hdr.side=unit[drive].track%unit[drive].type->heads;  in ms_putsec()
1311 /*data crc + jd's special gap (long words :-/) */  in ms_putsec()
1335 	if (unit[disk].type->sect_mult==2)  /* check for HD-Disks */  in dos_write()
1350 	for(cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)  in dos_write()
1363 /* FIXME: this assumes the drive is still spinning -
1368 	unsigned long nr = ((unsigned long)timer -  in flush_track_callback()
1381 	(*unit[nr].dtype->write_fkt)(nr);  in flush_track_callback()
1406 		(*unit[nr].dtype->write_fkt)(nr);  in non_int_flush_track()
1434 		return -1;  in get_track()
1444 			return -1;  in get_track()
1446 		error = (*unit[drive].dtype->read_fkt)(drive);  in get_track()
1452 		unit[drive].track = -1;  in get_track()
1456 	return -1;  in get_track()
1462 	int drive = floppy - unit;  in amiflop_rw_cur_segment()
1473 		track = block / (floppy->dtype->sects * floppy->type->sect_mult);  in amiflop_rw_cur_segment()
1474 		sector = block % (floppy->dtype->sects * floppy->type->sect_mult);  in amiflop_rw_cur_segment()
1475 		data = bio_data(rq->bio) + 512 * cnt;  in amiflop_rw_cur_segment()
1481 		if (get_track(drive, track) == -1)  in amiflop_rw_cur_segment()
1485 			memcpy(data, floppy->trackbuf + sector * 512, 512);  in amiflop_rw_cur_segment()
1487 			memcpy(floppy->trackbuf + sector * 512, data, 512);  in amiflop_rw_cur_segment()
1496 			floppy->dirty = 1;  in amiflop_rw_cur_segment()
1508 	struct request *rq = bd->rq;  in amiflop_queue_rq()
1509 	struct amiga_floppy_struct *floppy = rq->q->disk->private_data;  in amiflop_queue_rq()
1528 	int drive = MINOR(bdev->bd_dev) & 3;  in fd_getgeo()
1530 	geo->heads = unit[drive].type->heads;  in fd_getgeo()
1531 	geo->sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;  in fd_getgeo()
1532 	geo->cylinders = unit[drive].type->tracks;  in fd_getgeo()
1539 	struct amiga_floppy_struct *p = bdev->bd_disk->private_data;  in fd_locked_ioctl()
1540 	int drive = p - unit;  in fd_locked_ioctl()
1549 			return -EBUSY;  in fd_locked_ioctl()
1553 			return -ENODEV;  in fd_locked_ioctl()
1557 			return -ENXIO;  in fd_locked_ioctl()
1563 		if (param < p->type->tracks * p->type->heads)  in fd_locked_ioctl()
1567 				memset(p->trackbuf, FD_FILL_BYTE,  in fd_locked_ioctl()
1568 				       p->dtype->sects * p->type->sect_mult * 512);  in fd_locked_ioctl()
1575 			return -EINVAL;  in fd_locked_ioctl()
1583 		getprm.track=p->type->tracks;  in fd_locked_ioctl()
1584 		getprm.head=p->type->heads;  in fd_locked_ioctl()
1585 		getprm.sect=p->dtype->sects * p->type->sect_mult;  in fd_locked_ioctl()
1586 		getprm.size=p->blocks;  in fd_locked_ioctl()
1588 			return -EFAULT;  in fd_locked_ioctl()
1592 		return -EINVAL;  in fd_locked_ioctl()
1599 		if (copy_to_user(argp, raw_buf, p->type->read_size))  in fd_locked_ioctl()
1600 			return -EFAULT;  in fd_locked_ioctl()
1602 			return p->type->read_size;  in fd_locked_ioctl()
1605 		return -ENOSYS;  in fd_locked_ioctl()
1639 		unit[drive].type = &drive_types[num_dr_types-1]; /* FD_NODRIVE */  in fd_probe()
1644 	unit[drive].track = -1;  in fd_probe()
1646 	unit[drive].disk = -1;  in fd_probe()
1647 	unit[drive].motor = 0;  in fd_probe()
1649 	unit[drive].status = -1;  in fd_probe()
1659 	int drive = disk->first_minor & 3;  in floppy_open()
1660 	int system = (disk->first_minor & 4) >> 2;  in floppy_open()
1669 		return -EBUSY;  in floppy_open()
1672 	if (unit[drive].type->code == FD_NODRIVE) {  in floppy_open()
1674 		return -ENXIO;  in floppy_open()
1689 				return -EROFS;  in floppy_open()
1699 	unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*  in floppy_open()
1700 		data_types[system].sects*unit[drive].type->sect_mult;  in floppy_open()
1703 	printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,  in floppy_open()
1704 	       unit[drive].type->name, data_types[system].name);  in floppy_open()
1712 	struct amiga_floppy_struct *p = disk->private_data;  in floppy_release()
1713 	int drive = p - unit;  in floppy_release()
1721 	if (!fd_ref[drive]--) {  in floppy_release()
1733  * here, sleep etc. Note that floppy-on tries to set current_DOR to point
1739 	struct amiga_floppy_struct *p = disk->private_data;  in amiga_check_events()
1740 	int drive = p - unit;  in amiga_check_events()
1745 		changed = first_time--;  in amiga_check_events()
1756 		p->track = -1;  in amiga_check_events()
1757 		p->dirty = 0;  in amiga_check_events()
1790 	disk->major = FLOPPY_MAJOR;  in fd_alloc_disk()
1791 	disk->first_minor = drive + system;  in fd_alloc_disk()
1792 	disk->minors = 1;  in fd_alloc_disk()
1793 	disk->fops = &floppy_fops;  in fd_alloc_disk()
1794 	disk->flags |= GENHD_FL_NO_PART;  in fd_alloc_disk()
1795 	disk->events = DISK_EVENT_MEDIA_CHANGE;  in fd_alloc_disk()
1797 		sprintf(disk->disk_name, "fd%d_msdos", drive);  in fd_alloc_disk()
1799 		sprintf(disk->disk_name, "fd%d", drive);  in fd_alloc_disk()
1800 	disk->private_data = &unit[drive];  in fd_alloc_disk()
1837 	unit[drive].type->code = FD_NODRIVE;  in fd_alloc_drive()
1838 	return -ENOMEM;  in fd_alloc_drive()
1850 		if (unit[drive].type->code == FD_NODRIVE)  in fd_probe_drives()
1867 	return -ENOMEM;  in fd_probe_drives()
1875 		return -EBUSY;  in amiga_floppy_probe()
1877 	ret = -ENOMEM;  in amiga_floppy_probe()
1884 	ret = -EBUSY;  in amiga_floppy_probe()
1895 	ret = -ENODEV;  in amiga_floppy_probe()
1908 		unit[i].track = -1;  in amiga_floppy_probe()
1923 	ciaa.crb = 8; /* one-shot, stop */  in amiga_floppy_probe()
1938 	.driver   = {
1939 		.name	= "amiga-floppy",
1966 MODULE_ALIAS("platform:amiga-floppy");