xref: /freebsd/sys/dev/fdc/fdc.c (revision a6e4d8c45383824144e371bb6adc8e877611c4c9)
1 /*-
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Don Ahn.
7  *
8  * Libretto PCMCIA floppy support by David Horwitt (dhorwitt@ucsd.edu)
9  * aided by the Linux floppy driver modifications from David Bateman
10  * (dbateman@eng.uts.edu.au).
11  *
12  * Copyright (c) 1993, 1994 by
13  *  jc@irbs.UUCP (John Capo)
14  *  vak@zebub.msk.su (Serge Vakulenko)
15  *  ache@astral.msk.su (Andrew A. Chernov)
16  *
17  * Copyright (c) 1993, 1994, 1995 by
18  *  joerg_wunsch@uriah.sax.de (Joerg Wunsch)
19  *  dufault@hda.com (Peter Dufault)
20  *
21  * Copyright (c) 2001 Joerg Wunsch,
22  *  joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch)
23  *
24  * Redistribution and use in source and binary forms, with or without
25  * modification, are permitted provided that the following conditions
26  * are met:
27  * 1. Redistributions of source code must retain the above copyright
28  *    notice, this list of conditions and the following disclaimer.
29  * 2. Redistributions in binary form must reproduce the above copyright
30  *    notice, this list of conditions and the following disclaimer in the
31  *    documentation and/or other materials provided with the distribution.
32  * 4. Neither the name of the University nor the names of its contributors
33  *    may be used to endorse or promote products derived from this software
34  *    without specific prior written permission.
35  *
36  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
37  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
40  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46  * SUCH DAMAGE.
47  *
48  *	from:	@(#)fd.c	7.4 (Berkeley) 5/25/91
49  */
50 
51 #include <sys/cdefs.h>
52 __FBSDID("$FreeBSD$");
53 
54 #include "opt_fdc.h"
55 
56 #include <sys/param.h>
57 #include <sys/bio.h>
58 #include <sys/bus.h>
59 #include <sys/devicestat.h>
60 #include <sys/disk.h>
61 #include <sys/fcntl.h>
62 #include <sys/fdcio.h>
63 #include <sys/filio.h>
64 #include <sys/kernel.h>
65 #include <sys/lock.h>
66 #include <sys/malloc.h>
67 #include <sys/module.h>
68 #include <sys/mutex.h>
69 #include <sys/proc.h>
70 #include <sys/rman.h>
71 #include <sys/systm.h>
72 
73 #include <machine/bus.h>
74 #include <machine/clock.h>
75 #include <machine/stdarg.h>
76 
77 #include <isa/isavar.h>
78 #include <isa/isareg.h>
79 #include <dev/fdc/fdcreg.h>
80 #include <dev/fdc/fdcvar.h>
81 #include <isa/rtc.h>
82 
83 #define FDBIO_FORMAT	BIO_CMD2
84 
85 /* configuration flags for fdc */
86 #define FDC_NO_FIFO	(1 << 2)	/* do not enable FIFO  */
87 
88 /*
89  * Stop retrying after this many DMA overruns.  Since each retry takes
90  * one revolution, with 300 rpm., 25 retries take approximately 5
91  * seconds which the read attempt will block in case the DMA overrun
92  * is persistent.
93  */
94 #define FDC_DMAOV_MAX	25
95 
96 /*
97  * Timeout value for the PIO loops to wait until the FDC main status
98  * register matches our expectations (request for master, direction
99  * bit).  This is supposed to be a number of microseconds, although
100  * timing might actually not be very accurate.
101  *
102  * Timeouts of 100 msec are believed to be required for some broken
103  * (old) hardware.
104  */
105 #define	FDSTS_TIMEOUT	100000
106 
107 /*
108  * Number of subdevices that can be used for different density types.
109  */
110 #define NUMDENS		16
111 
112 #define FDBIO_RDSECTID	BIO_CMD1
113 
114 /*
115  * List of native drive densities.  Order must match enum fd_drivetype
116  * in <sys/fdcio.h>.  Upon attaching the drive, each of the
117  * programmable subdevices is initialized with the native density
118  * definition.
119  */
120 static struct fd_type fd_native_types[] =
121 {
122 { 0 },				/* FDT_NONE */
123 {  9,2,0xFF,0x2A,40, 720,FDC_250KBPS,2,0x50,1,0,FL_MFM }, /* FDT_360K */
124 { 15,2,0xFF,0x1B,80,2400,FDC_500KBPS,2,0x54,1,0,FL_MFM }, /* FDT_12M  */
125 {  9,2,0xFF,0x20,80,1440,FDC_250KBPS,2,0x50,1,0,FL_MFM }, /* FDT_720K */
126 { 18,2,0xFF,0x1B,80,2880,FDC_500KBPS,2,0x6C,1,0,FL_MFM }, /* FDT_144M */
127 #if 0				/* we currently don't handle 2.88 MB */
128 { 36,2,0xFF,0x1B,80,5760,FDC_1MBPS,  2,0x4C,1,1,FL_MFM|FL_PERPND } /*FDT_288M*/
129 #else
130 { 18,2,0xFF,0x1B,80,2880,FDC_500KBPS,2,0x6C,1,0,FL_MFM }, /* FDT_144M */
131 #endif
132 };
133 
134 /*
135  * 360 KB 5.25" and 720 KB 3.5" drives don't have automatic density
136  * selection, they just start out with their native density (or lose).
137  * So 1.2 MB 5.25", 1.44 MB 3.5", and 2.88 MB 3.5" drives have their
138  * respective lists of densities to search for.
139  */
140 static struct fd_type fd_searchlist_12m[] = {
141 { 15,2,0xFF,0x1B,80,2400,FDC_500KBPS,2,0x54,1,0,FL_MFM }, /* 1.2M */
142 {  9,2,0xFF,0x23,40, 720,FDC_300KBPS,2,0x50,1,0,FL_MFM|FL_2STEP }, /* 360K */
143 {  9,2,0xFF,0x20,80,1440,FDC_300KBPS,2,0x50,1,0,FL_MFM }, /* 720K */
144 };
145 
146 static struct fd_type fd_searchlist_144m[] = {
147 { 18,2,0xFF,0x1B,80,2880,FDC_500KBPS,2,0x6C,1,0,FL_MFM }, /* 1.44M */
148 {  9,2,0xFF,0x20,80,1440,FDC_250KBPS,2,0x50,1,0,FL_MFM }, /* 720K */
149 };
150 
151 /* We search for 1.44M first since this is the most common case. */
152 static struct fd_type fd_searchlist_288m[] = {
153 { 18,2,0xFF,0x1B,80,2880,FDC_500KBPS,2,0x6C,1,0,FL_MFM }, /* 1.44M */
154 #if 0
155 { 36,2,0xFF,0x1B,80,5760,FDC_1MBPS,  2,0x4C,1,1,FL_MFM|FL_PERPND } /* 2.88M */
156 #endif
157 {  9,2,0xFF,0x20,80,1440,FDC_250KBPS,2,0x50,1,0,FL_MFM }, /* 720K */
158 };
159 
160 #define MAX_SEC_SIZE	(128 << 3)
161 #define MAX_CYLINDER	85	/* some people really stress their drives
162 				 * up to cyl 82 */
163 #define MAX_HEAD	1
164 
165 devclass_t fdc_devclass;
166 
167 /*
168  * Per drive structure (softc).
169  */
170 struct fd_data {
171 	struct	fdc_data *fdc;	/* pointer to controller structure */
172 	int	fdsu;		/* this units number on this controller */
173 	enum	fd_drivetype type; /* drive type */
174 	struct	fd_type *ft;	/* pointer to current type descriptor */
175 	struct	fd_type fts[NUMDENS]; /* type descriptors */
176 	int	flags;
177 #define	FD_OPEN		0x01	/* it's open		*/
178 #define	FD_NONBLOCK	0x02	/* O_NONBLOCK set	*/
179 #define	FD_ACTIVE	0x04	/* it's active		*/
180 #define	FD_MOTOR	0x08	/* motor should be on	*/
181 #define	FD_MOTOR_WAIT	0x10	/* motor coming up	*/
182 #define	FD_UA		0x20	/* force unit attention */
183 	int	skip;
184 	int	hddrv;
185 #define FD_NO_TRACK -2
186 	int	track;		/* where we think the head is */
187 	int	options;	/* user configurable options, see fdcio.h */
188 	struct	callout_handle toffhandle;
189 	struct	callout_handle tohandle;
190 	struct	devstat *device_stats;
191 	struct cdev *masterdev;
192 	device_t dev;
193 	fdu_t	fdu;
194 };
195 
196 struct fdc_ivars {
197 	int	fdunit;
198 	int	fdtype;
199 };
200 
201 static devclass_t fd_devclass;
202 
203 /* configuration flags for fd */
204 #define FD_TYPEMASK	0x0f	/* drive type, matches enum
205 				 * fd_drivetype; on i386 machines, if
206 				 * given as 0, use RTC type for fd0
207 				 * and fd1 */
208 #define FD_DTYPE(flags)	((flags) & FD_TYPEMASK)
209 #define FD_NO_CHLINE	0x10	/* drive does not support changeline
210 				 * aka. unit attention */
211 #define FD_NO_PROBE	0x20	/* don't probe drive (seek test), just
212 				 * assume it is there */
213 
214 /*
215  * Throughout this file the following conventions will be used:
216  *
217  * fd is a pointer to the fd_data struct for the drive in question
218  * fdc is a pointer to the fdc_data struct for the controller
219  * fdu is the floppy drive unit number
220  * fdcu is the floppy controller unit number
221  * fdsu is the floppy drive unit number on that controller. (sub-unit)
222  */
223 
224 /*
225  * Function declarations, same (chaotic) order as they appear in the
226  * file.  Re-ordering is too late now, it would only obfuscate the
227  * diffs against old and offspring versions (like the PC98 one).
228  *
229  * Anyone adding functions here, please keep this sequence the same
230  * as below -- makes locating a particular function in the body much
231  * easier.
232  */
233 static u_int8_t fdsts_rd(fdc_p);
234 static void fddata_wr(fdc_p, u_int8_t);
235 static u_int8_t fddata_rd(fdc_p);
236 #if 0
237 static u_int8_t fdin_rd(fdc_p);
238 #endif
239 static int fdc_err(struct fdc_data *, const char *);
240 static int enable_fifo(fdc_p fdc);
241 static int fd_sense_drive_status(fdc_p, int *);
242 static int fd_sense_int(fdc_p, int *, int *);
243 static int fd_read_status(fdc_p);
244 static int fd_probe(device_t);
245 static int fd_attach(device_t);
246 static int fd_detach(device_t);
247 static void set_motor(struct fdc_data *, int, int);
248 #  define TURNON 1
249 #  define TURNOFF 0
250 static timeout_t fd_turnoff;
251 static timeout_t fd_motor_on;
252 static void fd_turnon(struct fd_data *);
253 static void fdc_reset(fdc_p);
254 static int fd_in(struct fdc_data *, int *);
255 static int out_fdc(struct fdc_data *, int);
256 /*
257  * The open function is named fdopen() to avoid confusion with fdopen()
258  * in fd(4).  The difference is now only meaningful for debuggers.
259  */
260 static	d_open_t	fdopen;
261 static	d_close_t	fdclose;
262 static	d_strategy_t	fdstrategy;
263 static void fdstart(struct fdc_data *);
264 static timeout_t fd_iotimeout;
265 static timeout_t fd_pseudointr;
266 static driver_intr_t fdc_intr;
267 static int fdcpio(fdc_p, long, caddr_t, u_int);
268 static int fdautoselect(struct cdev *);
269 static int fdstate(struct fdc_data *);
270 static int retrier(struct fdc_data *);
271 static void fdbiodone(struct bio *);
272 static int fdmisccmd(struct cdev *, u_int, void *);
273 static	d_ioctl_t	fdioctl;
274 
275 static int fifo_threshold = 8;	/* XXX: should be accessible via sysctl */
276 
277 #ifdef	FDC_DEBUG
278 /* CAUTION: fd_debug causes huge amounts of logging output */
279 static int volatile fd_debug = 0;
280 #define TRACE0(arg) do { if (fd_debug) printf(arg); } while (0)
281 #define TRACE1(arg1, arg2) do { if (fd_debug) printf(arg1, arg2); } while (0)
282 #else /* FDC_DEBUG */
283 #define TRACE0(arg) do { } while (0)
284 #define TRACE1(arg1, arg2) do { } while (0)
285 #endif /* FDC_DEBUG */
286 
287 /*
288  * Bus space handling (access to low-level IO).
289  */
290 void
291 fdout_wr(fdc_p fdc, u_int8_t v)
292 {
293 	bus_space_write_1(fdc->portt, fdc->porth, FDOUT+fdc->port_off, v);
294 }
295 
296 static u_int8_t
297 fdsts_rd(fdc_p fdc)
298 {
299 	return bus_space_read_1(fdc->portt, fdc->porth, FDSTS+fdc->port_off);
300 }
301 
302 static void
303 fddata_wr(fdc_p fdc, u_int8_t v)
304 {
305 	bus_space_write_1(fdc->portt, fdc->porth, FDDATA+fdc->port_off, v);
306 }
307 
308 static u_int8_t
309 fddata_rd(fdc_p fdc)
310 {
311 	return bus_space_read_1(fdc->portt, fdc->porth, FDDATA+fdc->port_off);
312 }
313 
314 static u_int8_t
315 fdin_rd(fdc_p fdc)
316 {
317 	return bus_space_read_1(fdc->portt, fdc->porth, FDIN);
318 }
319 
320 static struct cdevsw fd_cdevsw = {
321 	.d_version =	D_VERSION,
322 	.d_open =	fdopen,
323 	.d_close =	fdclose,
324 	.d_read =	physread,
325 	.d_write =	physwrite,
326 	.d_ioctl =	fdioctl,
327 	.d_strategy =	fdstrategy,
328 	.d_name =	"fd",
329 	.d_flags =	D_DISK | D_NEEDGIANT,
330 };
331 
332 /*
333  * Auxiliary functions.  Well, some only.  Others are scattered
334  * throughout the entire file.
335  */
336 static int
337 fdc_err(struct fdc_data *fdc, const char *s)
338 {
339 	fdc->fdc_errs++;
340 	if (s) {
341 		if (fdc->fdc_errs < FDC_ERRMAX)
342 			device_printf(fdc->fdc_dev, "%s", s);
343 		else if (fdc->fdc_errs == FDC_ERRMAX)
344 			device_printf(fdc->fdc_dev, "too many errors, not "
345 						    "logging any more\n");
346 	}
347 
348 	return FD_FAILED;
349 }
350 
351 /*
352  * fd_cmd: Send a command to the chip.  Takes a varargs with this structure:
353  * Unit number,
354  * # of output bytes, output bytes as ints ...,
355  * # of input bytes, input bytes as ints ...
356  */
357 int
358 fd_cmd(struct fdc_data *fdc, int n_out, ...)
359 {
360 	u_char cmd;
361 	int n_in;
362 	int n;
363 	va_list ap;
364 
365 	va_start(ap, n_out);
366 	cmd = (u_char)(va_arg(ap, int));
367 	va_end(ap);
368 	va_start(ap, n_out);
369 	for (n = 0; n < n_out; n++)
370 	{
371 		if (out_fdc(fdc, va_arg(ap, int)) < 0)
372 		{
373 			char msg[50];
374 			snprintf(msg, sizeof(msg),
375 				"cmd %x failed at out byte %d of %d\n",
376 				cmd, n + 1, n_out);
377 			return fdc_err(fdc, msg);
378 		}
379 	}
380 	n_in = va_arg(ap, int);
381 	for (n = 0; n < n_in; n++)
382 	{
383 		int *ptr = va_arg(ap, int *);
384 		if (fd_in(fdc, ptr) < 0)
385 		{
386 			char msg[50];
387 			snprintf(msg, sizeof(msg),
388 				"cmd %02x failed at in byte %d of %d\n",
389 				cmd, n + 1, n_in);
390 			return fdc_err(fdc, msg);
391 		}
392 	}
393 
394 	return 0;
395 }
396 
397 static int
398 enable_fifo(fdc_p fdc)
399 {
400 	int i, j;
401 
402 	if ((fdc->flags & FDC_HAS_FIFO) == 0) {
403 
404 		/*
405 		 * Cannot use fd_cmd the normal way here, since
406 		 * this might be an invalid command. Thus we send the
407 		 * first byte, and check for an early turn of data directon.
408 		 */
409 
410 		if (out_fdc(fdc, I8207X_CONFIGURE) < 0)
411 			return fdc_err(fdc, "Enable FIFO failed\n");
412 
413 		/* If command is invalid, return */
414 		j = FDSTS_TIMEOUT;
415 		while ((i = fdsts_rd(fdc) & (NE7_DIO | NE7_RQM))
416 		       != NE7_RQM && j-- > 0) {
417 			if (i == (NE7_DIO | NE7_RQM)) {
418 				fdc_reset(fdc);
419 				return FD_FAILED;
420 			}
421 			DELAY(1);
422 		}
423 		if (j<0 ||
424 		    fd_cmd(fdc, 3,
425 			   0, (fifo_threshold - 1) & 0xf, 0, 0) < 0) {
426 			fdc_reset(fdc);
427 			return fdc_err(fdc, "Enable FIFO failed\n");
428 		}
429 		fdc->flags |= FDC_HAS_FIFO;
430 		return 0;
431 	}
432 	if (fd_cmd(fdc, 4,
433 		   I8207X_CONFIGURE, 0, (fifo_threshold - 1) & 0xf, 0, 0) < 0)
434 		return fdc_err(fdc, "Re-enable FIFO failed\n");
435 	return 0;
436 }
437 
438 static int
439 fd_sense_drive_status(fdc_p fdc, int *st3p)
440 {
441 	int st3;
442 
443 	if (fd_cmd(fdc, 2, NE7CMD_SENSED, fdc->fdu, 1, &st3))
444 	{
445 		return fdc_err(fdc, "Sense Drive Status failed\n");
446 	}
447 	if (st3p)
448 		*st3p = st3;
449 
450 	return 0;
451 }
452 
453 static int
454 fd_sense_int(fdc_p fdc, int *st0p, int *cylp)
455 {
456 	int cyl, st0, ret;
457 
458 	ret = fd_cmd(fdc, 1, NE7CMD_SENSEI, 1, &st0);
459 	if (ret) {
460 		(void)fdc_err(fdc,
461 			      "sense intr err reading stat reg 0\n");
462 		return ret;
463 	}
464 
465 	if (st0p)
466 		*st0p = st0;
467 
468 	if ((st0 & NE7_ST0_IC) == NE7_ST0_IC_IV) {
469 		/*
470 		 * There doesn't seem to have been an interrupt.
471 		 */
472 		return FD_NOT_VALID;
473 	}
474 
475 	if (fd_in(fdc, &cyl) < 0) {
476 		return fdc_err(fdc, "can't get cyl num\n");
477 	}
478 
479 	if (cylp)
480 		*cylp = cyl;
481 
482 	return 0;
483 }
484 
485 
486 static int
487 fd_read_status(fdc_p fdc)
488 {
489 	int i, ret;
490 
491 	for (i = ret = 0; i < 7; i++) {
492 		/*
493 		 * XXX types are poorly chosen.  Only bytes can be read
494 		 * from the hardware, but fdc->status[] wants u_ints and
495 		 * fd_in() gives ints.
496 		 */
497 		int status;
498 
499 		ret = fd_in(fdc, &status);
500 		fdc->status[i] = status;
501 		if (ret != 0)
502 			break;
503 	}
504 
505 	if (ret == 0)
506 		fdc->flags |= FDC_STAT_VALID;
507 	else
508 		fdc->flags &= ~FDC_STAT_VALID;
509 
510 	return ret;
511 }
512 
513 void
514 fdc_release_resources(struct fdc_data *fdc)
515 {
516 	device_t dev;
517 
518 	dev = fdc->fdc_dev;
519 	if (fdc->fdc_intr) {
520 		BUS_TEARDOWN_INTR(device_get_parent(dev), dev, fdc->res_irq,
521 		    fdc->fdc_intr);
522 		fdc->fdc_intr = NULL;
523 	}
524 	if (fdc->res_irq != 0) {
525 		bus_deactivate_resource(dev, SYS_RES_IRQ, fdc->rid_irq,
526 					fdc->res_irq);
527 		bus_release_resource(dev, SYS_RES_IRQ, fdc->rid_irq,
528 				     fdc->res_irq);
529 		fdc->res_irq = NULL;
530 	}
531 	if (fdc->res_ctl != 0) {
532 		bus_deactivate_resource(dev, SYS_RES_IOPORT, fdc->rid_ctl,
533 					fdc->res_ctl);
534 		bus_release_resource(dev, SYS_RES_IOPORT, fdc->rid_ctl,
535 				     fdc->res_ctl);
536 		fdc->res_ctl = NULL;
537 	}
538 	if (fdc->res_ioport != 0) {
539 		bus_deactivate_resource(dev, SYS_RES_IOPORT, fdc->rid_ioport,
540 					fdc->res_ioport);
541 		bus_release_resource(dev, SYS_RES_IOPORT, fdc->rid_ioport,
542 				     fdc->res_ioport);
543 		fdc->res_ioport = NULL;
544 	}
545 	if (fdc->res_drq != 0) {
546 		bus_deactivate_resource(dev, SYS_RES_DRQ, fdc->rid_drq,
547 					fdc->res_drq);
548 		bus_release_resource(dev, SYS_RES_DRQ, fdc->rid_drq,
549 				     fdc->res_drq);
550 		fdc->res_ioport = NULL;
551 	}
552 }
553 
554 /*
555  * Configuration/initialization stuff, per controller.
556  */
557 
558 int
559 fdc_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
560 {
561 	struct fdc_ivars *ivars = device_get_ivars(child);
562 
563 	switch (which) {
564 	case FDC_IVAR_FDUNIT:
565 		*result = ivars->fdunit;
566 		break;
567 	case FDC_IVAR_FDTYPE:
568 		*result = ivars->fdtype;
569 		break;
570 	default:
571 		return (ENOENT);
572 	}
573 	return (0);
574 }
575 
576 int
577 fdc_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
578 {
579 	struct fdc_ivars *ivars = device_get_ivars(child);
580 
581 	switch (which) {
582 	case FDC_IVAR_FDUNIT:
583 		ivars->fdunit = value;
584 		break;
585 	case FDC_IVAR_FDTYPE:
586 		ivars->fdtype = value;
587 		break;
588 	default:
589 		return (ENOENT);
590 	}
591 	return (0);
592 }
593 
594 int
595 fdc_initial_reset(struct fdc_data *fdc)
596 {
597 	/* First, reset the floppy controller. */
598 	fdout_wr(fdc, 0);
599 	DELAY(100);
600 	fdout_wr(fdc, FDO_FRST);
601 
602 	/* Then, see if it can handle a command. */
603 	if (fd_cmd(fdc, 3, NE7CMD_SPECIFY, NE7_SPEC_1(3, 240),
604 	    NE7_SPEC_2(2, 0), 0))
605 		return (ENXIO);
606 	return (0);
607 }
608 
609 int
610 fdc_detach(device_t dev)
611 {
612 	struct	fdc_data *fdc;
613 	int	error;
614 
615 	fdc = device_get_softc(dev);
616 
617 	/* have our children detached first */
618 	if ((error = bus_generic_detach(dev)))
619 		return (error);
620 
621 	/* reset controller, turn motor off */
622 	fdout_wr(fdc, 0);
623 
624 	fdc_release_resources(fdc);
625 	return (0);
626 }
627 
628 /*
629  * Add a child device to the fdc controller.  It will then be probed etc.
630  */
631 device_t
632 fdc_add_child(device_t dev, const char *name, int unit)
633 {
634 	int flags;
635 	struct fdc_ivars *ivar;
636 	device_t child;
637 
638 	ivar = malloc(sizeof *ivar, M_DEVBUF /* XXX */, M_NOWAIT | M_ZERO);
639 	if (ivar == NULL)
640 		return (NULL);
641 	child = device_add_child(dev, name, unit);
642 	if (child == NULL) {
643 		free(ivar, M_DEVBUF);
644 		return (NULL);
645 	}
646 	device_set_ivars(child, ivar);
647 	ivar->fdunit = unit;
648 	ivar->fdtype = FDT_NONE;
649 	if (resource_int_value(name, unit, "flags", &flags) == 0)
650 		device_set_flags(child, flags);
651 	if (resource_disabled(name, unit))
652 		device_disable(child);
653 	return (child);
654 }
655 
656 int
657 fdc_attach(device_t dev)
658 {
659 	struct	fdc_data *fdc;
660 	int	error;
661 
662 	fdc = device_get_softc(dev);
663 	fdc->fdc_dev = dev;
664 	error = BUS_SETUP_INTR(device_get_parent(dev), dev, fdc->res_irq,
665 			       INTR_TYPE_BIO | INTR_ENTROPY, fdc_intr, fdc,
666 			       &fdc->fdc_intr);
667 	if (error) {
668 		device_printf(dev, "cannot setup interrupt\n");
669 		return error;
670 	}
671 	fdc->fdcu = device_get_unit(dev);
672 	fdc->flags |= FDC_NEEDS_RESET;
673 
674 	fdc->state = DEVIDLE;
675 
676 	/* reset controller, turn motor off, clear fdout mirror reg */
677 	fdout_wr(fdc, fdc->fdout = 0);
678 	bioq_init(&fdc->head);
679 
680 	return (0);
681 }
682 
683 int
684 fdc_hints_probe(device_t dev)
685 {
686 	const char *name, *dname;
687 	int i, error, dunit;
688 
689 	/*
690 	 * Probe and attach any children.  We should probably detect
691 	 * devices from the BIOS unless overridden.
692 	 */
693 	name = device_get_nameunit(dev);
694 	i = 0;
695 	while ((resource_find_match(&i, &dname, &dunit, "at", name)) == 0) {
696 		resource_int_value(dname, dunit, "drive", &dunit);
697 		fdc_add_child(dev, dname, dunit);
698 	}
699 
700 	if ((error = bus_generic_attach(dev)) != 0)
701 		return (error);
702 	return (0);
703 }
704 
705 int
706 fdc_print_child(device_t me, device_t child)
707 {
708 	int retval = 0, flags;
709 
710 	retval += bus_print_child_header(me, child);
711 	retval += printf(" on %s drive %d", device_get_nameunit(me),
712 	       fdc_get_fdunit(child));
713 	if ((flags = device_get_flags(me)) != 0)
714 		retval += printf(" flags %#x", flags);
715 	retval += printf("\n");
716 
717 	return (retval);
718 }
719 
720 /*
721  * Configuration/initialization, per drive.
722  */
723 static int
724 fd_probe(device_t dev)
725 {
726 	int	i;
727 	u_int	st0, st3;
728 	struct	fd_data *fd;
729 	struct	fdc_data *fdc;
730 	fdsu_t	fdsu;
731 	int	flags, type;
732 
733 	fdsu = fdc_get_fdunit(dev);
734 	fd = device_get_softc(dev);
735 	fdc = device_get_softc(device_get_parent(dev));
736 	flags = device_get_flags(dev);
737 
738 	fd->dev = dev;
739 	fd->fdc = fdc;
740 	fd->fdsu = fdsu;
741 	fd->fdu = device_get_unit(dev);
742 
743 	/* Auto-probe if fdinfo is present, but always allow override. */
744 	type = FD_DTYPE(flags);
745 	if (type == FDT_NONE && (type = fdc_get_fdtype(dev)) != FDT_NONE) {
746 		fd->type = type;
747 		goto done;
748 	} else {
749 		/* make sure fdautoselect() will be called */
750 		fd->flags = FD_UA;
751 		fd->type = type;
752 	}
753 
754 /*
755  * XXX I think using __i386__ is wrong here since we actually want to probe
756  * for the machine type, not the CPU type (so non-PC arch's like the PC98 will
757  * fail the probe).  However, for whatever reason, testing for _MACHINE_ARCH
758  * == i386 breaks the test on FreeBSD/Alpha.
759  */
760 #if defined(__i386__) || defined(__amd64__)
761 	if (fd->type == FDT_NONE && (fd->fdu == 0 || fd->fdu == 1)) {
762 		/* Look up what the BIOS thinks we have. */
763 		if (fd->fdu == 0) {
764 			if ((fdc->flags & FDC_ISPCMCIA))
765 				/*
766 				 * Somewhat special.  No need to force the
767 				 * user to set device flags, since the Y-E
768 				 * Data PCMCIA floppy is always a 1.44 MB
769 				 * device.
770 				 */
771 				fd->type = FDT_144M;
772 			else
773 				fd->type = (rtcin(RTC_FDISKETTE) & 0xf0) >> 4;
774 		} else {
775 			fd->type = rtcin(RTC_FDISKETTE) & 0x0f;
776 		}
777 		if (fd->type == FDT_288M_1)
778 			fd->type = FDT_288M;
779 	}
780 #endif /* __i386__ || __amd64__ */
781 	/* is there a unit? */
782 	if (fd->type == FDT_NONE)
783 		return (ENXIO);
784 
785 	/* select it */
786 	set_motor(fdc, fdsu, TURNON);
787 	fdc_reset(fdc);		/* XXX reset, then unreset, etc. */
788 	DELAY(1000000);	/* 1 sec */
789 
790 	if ((flags & FD_NO_PROBE) == 0) {
791 		/* If we're at track 0 first seek inwards. */
792 		if ((fd_sense_drive_status(fdc, &st3) == 0) &&
793 		    (st3 & NE7_ST3_T0)) {
794 			/* Seek some steps... */
795 			if (fd_cmd(fdc, 3, NE7CMD_SEEK, fdsu, 10, 0) == 0) {
796 				/* ...wait a moment... */
797 				DELAY(300000);
798 				/* make ctrlr happy: */
799 				fd_sense_int(fdc, 0, 0);
800 			}
801 		}
802 
803 		for (i = 0; i < 2; i++) {
804 			/*
805 			 * we must recalibrate twice, just in case the
806 			 * heads have been beyond cylinder 76, since
807 			 * most FDCs still barf when attempting to
808 			 * recalibrate more than 77 steps
809 			 */
810 			/* go back to 0: */
811 			if (fd_cmd(fdc, 2, NE7CMD_RECAL, fdsu, 0) == 0) {
812 				/* a second being enough for full stroke seek*/
813 				DELAY(i == 0 ? 1000000 : 300000);
814 
815 				/* anything responding? */
816 				if (fd_sense_int(fdc, &st0, 0) == 0 &&
817 				    (st0 & NE7_ST0_EC) == 0)
818 					break; /* already probed succesfully */
819 			}
820 		}
821 	}
822 
823 	set_motor(fdc, fdsu, TURNOFF);
824 
825 	if ((flags & FD_NO_PROBE) == 0 &&
826 	    (st0 & NE7_ST0_EC) != 0) /* no track 0 -> no drive present */
827 		return (ENXIO);
828 
829 done:
830 	/* This doesn't work before the first reset. */
831 	if ((fdc->flags & FDC_HAS_FIFO) == 0 &&
832 	    fdc->fdct == FDC_ENHANCED &&
833 	    (device_get_flags(fdc->fdc_dev) & FDC_NO_FIFO) == 0 &&
834 	    enable_fifo(fdc) == 0) {
835 		device_printf(device_get_parent(dev),
836 		    "FIFO enabled, %d bytes threshold\n", fifo_threshold);
837 	}
838 
839 	switch (fd->type) {
840 	case FDT_12M:
841 		device_set_desc(dev, "1200-KB 5.25\" drive");
842 		break;
843 	case FDT_144M:
844 		device_set_desc(dev, "1440-KB 3.5\" drive");
845 		break;
846 	case FDT_288M:
847 		device_set_desc(dev, "2880-KB 3.5\" drive (in 1440-KB mode)");
848 		break;
849 	case FDT_360K:
850 		device_set_desc(dev, "360-KB 5.25\" drive");
851 		break;
852 	case FDT_720K:
853 		device_set_desc(dev, "720-KB 3.5\" drive");
854 		break;
855 	default:
856 		return (ENXIO);
857 	}
858 	fd->track = FD_NO_TRACK;
859 	fd->fdc = fdc;
860 	fd->fdsu = fdsu;
861 	fd->options = 0;
862 	callout_handle_init(&fd->toffhandle);
863 	callout_handle_init(&fd->tohandle);
864 
865 	/* initialize densities for subdevices */
866 	for (i = 0; i < NUMDENS; i++)
867 		memcpy(fd->fts + i, fd_native_types + fd->type,
868 		       sizeof(struct fd_type));
869 	return (0);
870 }
871 
872 static int
873 fd_attach(device_t dev)
874 {
875 	struct	fd_data *fd;
876 
877 	fd = device_get_softc(dev);
878 	fd->masterdev = make_dev(&fd_cdevsw, fd->fdu,
879 				 UID_ROOT, GID_OPERATOR, 0640, "fd%d", fd->fdu);
880 	fd->masterdev->si_drv1 = fd;
881 	fd->device_stats = devstat_new_entry(device_get_name(dev),
882 			  device_get_unit(dev), 0, DEVSTAT_NO_ORDERED_TAGS,
883 			  DEVSTAT_TYPE_FLOPPY | DEVSTAT_TYPE_IF_OTHER,
884 			  DEVSTAT_PRIORITY_FD);
885 	return (0);
886 }
887 
888 static int
889 fd_detach(device_t dev)
890 {
891 	struct	fd_data *fd;
892 
893 	fd = device_get_softc(dev);
894 	untimeout(fd_turnoff, fd, fd->toffhandle);
895 	devstat_remove_entry(fd->device_stats);
896 	destroy_dev(fd->masterdev);
897 
898 	return (0);
899 }
900 
901 static device_method_t fd_methods[] = {
902 	/* Device interface */
903 	DEVMETHOD(device_probe,		fd_probe),
904 	DEVMETHOD(device_attach,	fd_attach),
905 	DEVMETHOD(device_detach,	fd_detach),
906 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
907 	DEVMETHOD(device_suspend,	bus_generic_suspend), /* XXX */
908 	DEVMETHOD(device_resume,	bus_generic_resume), /* XXX */
909 
910 	{ 0, 0 }
911 };
912 
913 static driver_t fd_driver = {
914 	"fd",
915 	fd_methods,
916 	sizeof(struct fd_data)
917 };
918 
919 DRIVER_MODULE(fd, fdc, fd_driver, fd_devclass, 0, 0);
920 
921 /*
922  * More auxiliary functions.
923  */
924 /*
925  * Motor control stuff.
926  * Remember to not deselect the drive we're working on.
927  */
928 static void
929 set_motor(struct fdc_data *fdc, int fdsu, int turnon)
930 {
931 	int fdout;
932 
933 	fdout = fdc->fdout;
934 	if (turnon) {
935 		fdout &= ~FDO_FDSEL;
936 		fdout |= (FDO_MOEN0 << fdsu) | FDO_FDMAEN | FDO_FRST | fdsu;
937 	} else
938 		fdout &= ~(FDO_MOEN0 << fdsu);
939 	fdc->fdout = fdout;
940 	fdout_wr(fdc, fdout);
941 	TRACE1("[0x%x->FDOUT]", fdout);
942 }
943 
944 static void
945 fd_turnoff(void *xfd)
946 {
947 	int	s;
948 	fd_p fd = xfd;
949 
950 	TRACE1("[fd%d: turnoff]", fd->fdu);
951 
952 	s = splbio();
953 	/*
954 	 * Don't turn off the motor yet if the drive is active.
955 	 *
956 	 * If we got here, this could only mean we missed an interrupt.
957 	 * This can e. g. happen on the Y-E Date PCMCIA floppy controller
958 	 * after a controller reset.  Just schedule a pseudo-interrupt
959 	 * so the state machine gets re-entered.
960 	 */
961 	if (fd->fdc->state != DEVIDLE && fd->fdc->fdu == fd->fdu) {
962 		fdc_intr(fd->fdc);
963 		splx(s);
964 		return;
965 	}
966 
967 	fd->flags &= ~FD_MOTOR;
968 	set_motor(fd->fdc, fd->fdsu, TURNOFF);
969 	splx(s);
970 }
971 
972 static void
973 fd_motor_on(void *xfd)
974 {
975 	int	s;
976 	fd_p fd = xfd;
977 
978 	s = splbio();
979 	fd->flags &= ~FD_MOTOR_WAIT;
980 	if((fd->fdc->fd == fd) && (fd->fdc->state == MOTORWAIT))
981 	{
982 		fdc_intr(fd->fdc);
983 	}
984 	splx(s);
985 }
986 
987 static void
988 fd_turnon(fd_p fd)
989 {
990 	if(!(fd->flags & FD_MOTOR))
991 	{
992 		fd->flags |= (FD_MOTOR + FD_MOTOR_WAIT);
993 		set_motor(fd->fdc, fd->fdsu, TURNON);
994 		timeout(fd_motor_on, fd, hz); /* in 1 sec its ok */
995 	}
996 }
997 
998 static void
999 fdc_reset(fdc_p fdc)
1000 {
1001 	/* Try a reset, keep motor on */
1002 	fdout_wr(fdc, fdc->fdout & ~(FDO_FRST|FDO_FDMAEN));
1003 	TRACE1("[0x%x->FDOUT]", fdc->fdout & ~(FDO_FRST|FDO_FDMAEN));
1004 	DELAY(100);
1005 	/* enable FDC, but defer interrupts a moment */
1006 	fdout_wr(fdc, fdc->fdout & ~FDO_FDMAEN);
1007 	TRACE1("[0x%x->FDOUT]", fdc->fdout & ~FDO_FDMAEN);
1008 	DELAY(100);
1009 	fdout_wr(fdc, fdc->fdout);
1010 	TRACE1("[0x%x->FDOUT]", fdc->fdout);
1011 
1012 	/* XXX after a reset, silently believe the FDC will accept commands */
1013 	(void)fd_cmd(fdc, 3, NE7CMD_SPECIFY,
1014 		     NE7_SPEC_1(3, 240), NE7_SPEC_2(2, 0),
1015 		     0);
1016 	if (fdc->flags & FDC_HAS_FIFO)
1017 		(void) enable_fifo(fdc);
1018 }
1019 
1020 /*
1021  * FDC IO functions, take care of the main status register, timeout
1022  * in case the desired status bits are never set.
1023  *
1024  * These PIO loops initially start out with short delays between
1025  * each iteration in the expectation that the required condition
1026  * is usually met quickly, so it can be handled immediately.  After
1027  * about 1 ms, stepping is increased to achieve a better timing
1028  * accuracy in the calls to DELAY().
1029  */
1030 static int
1031 fd_in(struct fdc_data *fdc, int *ptr)
1032 {
1033 	int i, j, step;
1034 
1035 	for (j = 0, step = 1;
1036 	    (i = fdsts_rd(fdc) & (NE7_DIO|NE7_RQM)) != (NE7_DIO|NE7_RQM) &&
1037 	    j < FDSTS_TIMEOUT;
1038 	    j += step) {
1039 		if (i == NE7_RQM)
1040 			return (fdc_err(fdc, "ready for output in input\n"));
1041 		if (j == 1000)
1042 			step = 1000;
1043 		DELAY(step);
1044 	}
1045 	if (j >= FDSTS_TIMEOUT)
1046 		return (fdc_err(fdc, bootverbose? "input ready timeout\n": 0));
1047 #ifdef	FDC_DEBUG
1048 	i = fddata_rd(fdc);
1049 	TRACE1("[FDDATA->0x%x]", (unsigned char)i);
1050 	*ptr = i;
1051 	return (0);
1052 #else	/* !FDC_DEBUG */
1053 	i = fddata_rd(fdc);
1054 	if (ptr)
1055 		*ptr = i;
1056 	return (0);
1057 #endif	/* FDC_DEBUG */
1058 }
1059 
1060 static int
1061 out_fdc(struct fdc_data *fdc, int x)
1062 {
1063 	int i, j, step;
1064 
1065 	for (j = 0, step = 1;
1066 	    (i = fdsts_rd(fdc) & (NE7_DIO|NE7_RQM)) != NE7_RQM &&
1067 	    j < FDSTS_TIMEOUT;
1068 	    j += step) {
1069 		if (i == (NE7_DIO|NE7_RQM))
1070 			return (fdc_err(fdc, "ready for input in output\n"));
1071 		if (j == 1000)
1072 			step = 1000;
1073 		DELAY(step);
1074 	}
1075 	if (j >= FDSTS_TIMEOUT)
1076 		return (fdc_err(fdc, bootverbose? "output ready timeout\n": 0));
1077 
1078 	/* Send the command and return */
1079 	fddata_wr(fdc, x);
1080 	TRACE1("[0x%x->FDDATA]", x);
1081 	return (0);
1082 }
1083 
1084 /*
1085  * Block device driver interface functions (interspersed with even more
1086  * auxiliary functions).
1087  */
1088 static int
1089 fdopen(struct cdev *dev, int flags, int mode, struct thread *td)
1090 {
1091 	fd_p	fd;
1092 	fdc_p	fdc;
1093  	int rv, unitattn, dflags;
1094 
1095 	fd = dev->si_drv1;
1096 	if (fd == NULL)
1097 		return (ENXIO);
1098 	fdc = fd->fdc;
1099 	if ((fdc == NULL) || (fd->type == FDT_NONE))
1100 		return (ENXIO);
1101 	dflags = device_get_flags(fd->dev);
1102 	/*
1103 	 * This is a bit bogus.  It's still possible that e. g. a
1104 	 * descriptor gets inherited to a child, but then it's at
1105 	 * least for the same subdevice.  By checking FD_OPEN here, we
1106 	 * can ensure that a device isn't attempted to be opened with
1107 	 * different densities at the same time where the second open
1108 	 * could clobber the settings from the first one.
1109 	 */
1110 	if (fd->flags & FD_OPEN)
1111 		return (EBUSY);
1112 
1113 	if (flags & FNONBLOCK) {
1114 		/*
1115 		 * Unfortunately, physio(9) discards its ioflag
1116 		 * argument, thus preventing us from seeing the
1117 		 * IO_NDELAY bit.  So we need to keep track
1118 		 * ourselves.
1119 		 */
1120 		fd->flags |= FD_NONBLOCK;
1121 		fd->ft = 0;
1122 	} else {
1123 		/*
1124 		 * Figure out a unit attention condition.
1125 		 *
1126 		 * If UA has been forced, proceed.
1127 		 *
1128 		 * If the drive has no changeline support,
1129 		 * or if the drive parameters have been lost
1130 		 * due to previous non-blocking access,
1131 		 * assume a forced UA condition.
1132 		 *
1133 		 * If motor is off, turn it on for a moment
1134 		 * and select our drive, in order to read the
1135 		 * UA hardware signal.
1136 		 *
1137 		 * If motor is on, and our drive is currently
1138 		 * selected, just read the hardware bit.
1139 		 *
1140 		 * If motor is on, but active for another
1141 		 * drive on that controller, we are lost.  We
1142 		 * cannot risk to deselect the other drive, so
1143 		 * we just assume a forced UA condition to be
1144 		 * on the safe side.
1145 		 */
1146 		unitattn = 0;
1147 		if ((dflags & FD_NO_CHLINE) != 0 ||
1148 		    (fd->flags & FD_UA) != 0 ||
1149 		    fd->ft == 0) {
1150 			unitattn = 1;
1151 			fd->flags &= ~FD_UA;
1152 		} else if (fdc->fdout & (FDO_MOEN0 | FDO_MOEN1 |
1153 					 FDO_MOEN2 | FDO_MOEN3)) {
1154 			if ((fdc->fdout & FDO_FDSEL) == fd->fdsu)
1155 				unitattn = fdin_rd(fdc) & FDI_DCHG;
1156 			else
1157 				unitattn = 1;
1158 		} else {
1159 			set_motor(fdc, fd->fdsu, TURNON);
1160 			unitattn = fdin_rd(fdc) & FDI_DCHG;
1161 			set_motor(fdc, fd->fdsu, TURNOFF);
1162 		}
1163 		if (unitattn && (rv = fdautoselect(dev)) != 0)
1164 			return (rv);
1165 	}
1166 	fd->flags |= FD_OPEN;
1167 
1168 	if ((fdc->flags & FDC_NODMA) == 0) {
1169 		if (fdc->dmacnt++ == 0) {
1170 			isa_dma_acquire(fdc->dmachan);
1171 			isa_dmainit(fdc->dmachan, MAX_SEC_SIZE);
1172 		}
1173 	}
1174 
1175 	/*
1176 	 * Clearing the DMA overrun counter at open time is a bit messy.
1177 	 * Since we're only managing one counter per controller, opening
1178 	 * the second drive could mess it up.  Anyway, if the DMA overrun
1179 	 * condition is really persistent, it will eventually time out
1180 	 * still.  OTOH, clearing it here will ensure we'll at least start
1181 	 * trying again after a previous (maybe even long ago) failure.
1182 	 * Also, this is merely a stop-gap measure only that should not
1183 	 * happen during normal operation, so we can tolerate it to be a
1184 	 * bit sloppy about this.
1185 	 */
1186 	fdc->dma_overruns = 0;
1187 
1188 	return 0;
1189 }
1190 
1191 static int
1192 fdclose(struct cdev *dev, int flags, int mode, struct thread *td)
1193 {
1194 	struct fd_data *fd;
1195  	fdc_p	fdc;
1196 
1197 	fd = dev->si_drv1;
1198 	fdc = fd->fdc;
1199 	fd->flags &= ~(FD_OPEN | FD_NONBLOCK);
1200 	fd->options &= ~(FDOPT_NORETRY | FDOPT_NOERRLOG | FDOPT_NOERROR);
1201 
1202 	if ((fdc->flags & FDC_NODMA) == 0)
1203 		if (--fdc->dmacnt == 0)
1204 			isa_dma_release(fdc->dmachan);
1205 
1206 	return (0);
1207 }
1208 
1209 static void
1210 fdstrategy(struct bio *bp)
1211 {
1212 	long blknum, nblocks;
1213  	int	s;
1214  	fdu_t	fdu;
1215  	fdc_p	fdc;
1216  	fd_p	fd;
1217 	size_t	fdblk;
1218 
1219 	fd = bp->bio_dev->si_drv1;
1220  	fdu = fd->fdu;
1221 	fdc = fd->fdc;
1222 	bp->bio_resid = bp->bio_bcount;
1223 	if (fd->type == FDT_NONE || fd->ft == 0) {
1224 		if (fd->type != FDT_NONE && (fd->flags & FD_NONBLOCK))
1225 			bp->bio_error = EAGAIN;
1226 		else
1227 			bp->bio_error = ENXIO;
1228 		bp->bio_flags |= BIO_ERROR;
1229 		goto bad;
1230 	}
1231 	fdblk = 128 << (fd->ft->secsize);
1232 	if (bp->bio_cmd != FDBIO_FORMAT && bp->bio_cmd != FDBIO_RDSECTID) {
1233 		if (fd->flags & FD_NONBLOCK) {
1234 			bp->bio_error = EAGAIN;
1235 			bp->bio_flags |= BIO_ERROR;
1236 			goto bad;
1237 		}
1238 		if (bp->bio_offset < 0) {
1239 			printf(
1240 		"fd%d: fdstrat: bad request offset = %ju, bcount = %ld\n",
1241 			       fdu, (intmax_t)bp->bio_offset, bp->bio_bcount);
1242 			bp->bio_error = EINVAL;
1243 			bp->bio_flags |= BIO_ERROR;
1244 			goto bad;
1245 		}
1246 		if ((bp->bio_bcount % fdblk) != 0) {
1247 			bp->bio_error = EINVAL;
1248 			bp->bio_flags |= BIO_ERROR;
1249 			goto bad;
1250 		}
1251 	}
1252 
1253 	/*
1254 	 * Set up block calculations.
1255 	 */
1256 	if (bp->bio_offset >= ((off_t)128 << fd->ft->secsize) * fd->ft->size) {
1257 		bp->bio_error = EINVAL;
1258 		bp->bio_flags |= BIO_ERROR;
1259 		goto bad;
1260 	}
1261 	blknum = bp->bio_offset / fdblk;
1262  	nblocks = fd->ft->size;
1263 	if (blknum + bp->bio_bcount / fdblk > nblocks) {
1264 		if (blknum >= nblocks) {
1265 			if (bp->bio_cmd != BIO_READ) {
1266 				bp->bio_error = ENOSPC;
1267 				bp->bio_flags |= BIO_ERROR;
1268 			}
1269 			goto bad;	/* not always bad, but EOF */
1270 		}
1271 		bp->bio_bcount = (nblocks - blknum) * fdblk;
1272 	}
1273  	bp->bio_pblkno = blknum;
1274 	s = splbio();
1275 	bioq_disksort(&fdc->head, bp);
1276 	untimeout(fd_turnoff, fd, fd->toffhandle); /* a good idea */
1277 	devstat_start_transaction_bio(fd->device_stats, bp);
1278 	device_busy(fd->dev);
1279 	fdstart(fdc);
1280 	splx(s);
1281 	return;
1282 
1283 bad:
1284 	biodone(bp);
1285 }
1286 
1287 /*
1288  * fdstart
1289  *
1290  * We have just queued something.  If the controller is not busy
1291  * then simulate the case where it has just finished a command
1292  * So that it (the interrupt routine) looks on the queue for more
1293  * work to do and picks up what we just added.
1294  *
1295  * If the controller is already busy, we need do nothing, as it
1296  * will pick up our work when the present work completes.
1297  */
1298 static void
1299 fdstart(struct fdc_data *fdc)
1300 {
1301 	int s;
1302 
1303 	s = splbio();
1304 	if(fdc->state == DEVIDLE)
1305 	{
1306 		fdc_intr(fdc);
1307 	}
1308 	splx(s);
1309 }
1310 
1311 static void
1312 fd_iotimeout(void *xfdc)
1313 {
1314  	fdc_p fdc;
1315 	int s;
1316 
1317 	fdc = xfdc;
1318 	TRACE1("fd%d[fd_iotimeout()]", fdc->fdu);
1319 
1320 	/*
1321 	 * Due to IBM's brain-dead design, the FDC has a faked ready
1322 	 * signal, hardwired to ready == true. Thus, any command
1323 	 * issued if there's no diskette in the drive will _never_
1324 	 * complete, and must be aborted by resetting the FDC.
1325 	 * Many thanks, Big Blue!
1326 	 * The FDC must not be reset directly, since that would
1327 	 * interfere with the state machine.  Instead, pretend that
1328 	 * the command completed but was invalid.  The state machine
1329 	 * will reset the FDC and retry once.
1330 	 */
1331 	s = splbio();
1332 	fdc->status[0] = NE7_ST0_IC_IV;
1333 	fdc->flags &= ~FDC_STAT_VALID;
1334 	fdc->state = IOTIMEDOUT;
1335 	fdc_intr(fdc);
1336 	splx(s);
1337 }
1338 
1339 /* Just ensure it has the right spl. */
1340 static void
1341 fd_pseudointr(void *xfdc)
1342 {
1343 	int	s;
1344 
1345 	s = splbio();
1346 	fdc_intr(xfdc);
1347 	splx(s);
1348 }
1349 
1350 /*
1351  * fdc_intr
1352  *
1353  * Keep calling the state machine until it returns a 0.
1354  * Always called at splbio.
1355  */
1356 static void
1357 fdc_intr(void *xfdc)
1358 {
1359 	fdc_p fdc = xfdc;
1360 	while(fdstate(fdc))
1361 		;
1362 }
1363 
1364 /*
1365  * Magic pseudo-DMA initialization for YE FDC. Sets count and
1366  * direction.
1367  */
1368 #define SET_BCDR(fdc,wr,cnt,port) \
1369 	bus_space_write_1(fdc->portt, fdc->porth, fdc->port_off + port,	 \
1370 	    ((cnt)-1) & 0xff);						 \
1371 	bus_space_write_1(fdc->portt, fdc->porth, fdc->port_off + port + 1, \
1372 	    ((wr ? 0x80 : 0) | ((((cnt)-1) >> 8) & 0x7f)));
1373 
1374 /*
1375  * fdcpio(): perform programmed IO read/write for YE PCMCIA floppy.
1376  */
1377 static int
1378 fdcpio(fdc_p fdc, long flags, caddr_t addr, u_int count)
1379 {
1380 	u_char *cptr = (u_char *)addr;
1381 
1382 	if (flags == BIO_READ) {
1383 		if (fdc->state != PIOREAD) {
1384 			fdc->state = PIOREAD;
1385 			return(0);
1386 		}
1387 		SET_BCDR(fdc, 0, count, 0);
1388 		bus_space_read_multi_1(fdc->portt, fdc->porth, fdc->port_off +
1389 		    FDC_YE_DATAPORT, cptr, count);
1390 	} else {
1391 		bus_space_write_multi_1(fdc->portt, fdc->porth, fdc->port_off +
1392 		    FDC_YE_DATAPORT, cptr, count);
1393 		SET_BCDR(fdc, 0, count, 0);
1394 	}
1395 	return(1);
1396 }
1397 
1398 /*
1399  * Try figuring out the density of the media present in our device.
1400  */
1401 static int
1402 fdautoselect(struct cdev *dev)
1403 {
1404  	fd_p fd;
1405 	struct fd_type *fdtp;
1406 	struct fdc_readid id;
1407 	int i, n, oopts, rv;
1408 
1409 	fd = dev->si_drv1;
1410 
1411 	switch (fd->type) {
1412 	default:
1413 		return (ENXIO);
1414 
1415 	case FDT_360K:
1416 	case FDT_720K:
1417 		/* no autoselection on those drives */
1418 		fd->ft = fd_native_types + fd->type;
1419 		return (0);
1420 
1421 	case FDT_12M:
1422 		fdtp = fd_searchlist_12m;
1423 		n = sizeof fd_searchlist_12m / sizeof(struct fd_type);
1424 		break;
1425 
1426 	case FDT_144M:
1427 		fdtp = fd_searchlist_144m;
1428 		n = sizeof fd_searchlist_144m / sizeof(struct fd_type);
1429 		break;
1430 
1431 	case FDT_288M:
1432 		fdtp = fd_searchlist_288m;
1433 		n = sizeof fd_searchlist_288m / sizeof(struct fd_type);
1434 		break;
1435 	}
1436 
1437 	/*
1438 	 * Try reading sector ID fields, first at cylinder 0, head 0,
1439 	 * then at cylinder 2, head N.  We don't probe cylinder 1,
1440 	 * since for 5.25in DD media in a HD drive, there are no data
1441 	 * to read (2 step pulses per media cylinder required).  For
1442 	 * two-sided media, the second probe always goes to head 1, so
1443 	 * we can tell them apart from single-sided media.  As a
1444 	 * side-effect this means that single-sided media should be
1445 	 * mentioned in the search list after two-sided media of an
1446 	 * otherwise identical density.  Media with a different number
1447 	 * of sectors per track but otherwise identical parameters
1448 	 * cannot be distinguished at all.
1449 	 *
1450 	 * If we successfully read an ID field on both cylinders where
1451 	 * the recorded values match our expectation, we are done.
1452 	 * Otherwise, we try the next density entry from the table.
1453 	 *
1454 	 * Stepping to cylinder 2 has the side-effect of clearing the
1455 	 * unit attention bit.
1456 	 */
1457 	oopts = fd->options;
1458 	fd->options |= FDOPT_NOERRLOG | FDOPT_NORETRY;
1459 	for (i = 0; i < n; i++, fdtp++) {
1460 		fd->ft = fdtp;
1461 
1462 		id.cyl = id.head = 0;
1463 		rv = fdmisccmd(dev, FDBIO_RDSECTID, &id);
1464 		if (rv != 0)
1465 			continue;
1466 		if (id.cyl != 0 || id.head != 0 ||
1467 		    id.secshift != fdtp->secsize)
1468 			continue;
1469 		id.cyl = 2;
1470 		id.head = fd->ft->heads - 1;
1471 		rv = fdmisccmd(dev, FDBIO_RDSECTID, &id);
1472 		if (id.cyl != 2 || id.head != fdtp->heads - 1 ||
1473 		    id.secshift != fdtp->secsize)
1474 			continue;
1475 		if (rv == 0)
1476 			break;
1477 	}
1478 
1479 	fd->options = oopts;
1480 	if (i == n) {
1481 		if (bootverbose)
1482 			device_printf(fd->dev, "autoselection failed\n");
1483 		fd->ft = 0;
1484 		return (EIO);
1485 	} else {
1486 		if (bootverbose)
1487 			device_printf(fd->dev, "autoselected %d KB medium\n",
1488 				      fd->ft->size / 2);
1489 		return (0);
1490 	}
1491 }
1492 
1493 
1494 /*
1495  * The controller state machine.
1496  *
1497  * If it returns a non zero value, it should be called again immediately.
1498  */
1499 static int
1500 fdstate(fdc_p fdc)
1501 {
1502 	struct fdc_readid *idp;
1503 	int read, format, rdsectid, cylinder, head, i, sec = 0, sectrac;
1504 	int st0, cyl, st3, idf, ne7cmd, mfm, steptrac;
1505 	unsigned long blknum;
1506 	fdu_t fdu = fdc->fdu;
1507 	fd_p fd;
1508 	register struct bio *bp;
1509 	struct fd_formb *finfo = NULL;
1510 	size_t fdblk;
1511 
1512 	bp = fdc->bp;
1513 	if (bp == NULL) {
1514 		bp = bioq_first(&fdc->head);
1515 		if (bp != NULL) {
1516 			bioq_remove(&fdc->head, bp);
1517 			fdc->bp = bp;
1518 		}
1519 	}
1520 	if (bp == NULL) {
1521 		/*
1522 		 * Nothing left for this controller to do,
1523 		 * force into the IDLE state.
1524 		 */
1525 		fdc->state = DEVIDLE;
1526 		if (fdc->fd) {
1527 			device_printf(fdc->fdc_dev,
1528 			    "unexpected valid fd pointer\n");
1529 			fdc->fd = (fd_p) 0;
1530 			fdc->fdu = -1;
1531 		}
1532 		TRACE1("[fdc%d IDLE]", fdc->fdcu);
1533  		return (0);
1534 	}
1535 	fd = bp->bio_dev->si_drv1;
1536 	fdu = fd->fdu;
1537 	fdblk = 128 << fd->ft->secsize;
1538 	if (fdc->fd && (fd != fdc->fd))
1539 		device_printf(fd->dev, "confused fd pointers\n");
1540 	read = bp->bio_cmd == BIO_READ;
1541 	mfm = (fd->ft->flags & FL_MFM)? NE7CMD_MFM: 0;
1542 	steptrac = (fd->ft->flags & FL_2STEP)? 2: 1;
1543 	if (read)
1544 		idf = ISADMA_READ;
1545 	else
1546 		idf = ISADMA_WRITE;
1547 	format = bp->bio_cmd == FDBIO_FORMAT;
1548 	rdsectid = bp->bio_cmd == FDBIO_RDSECTID;
1549 	if (format)
1550 		finfo = (struct fd_formb *)bp->bio_data;
1551 	TRACE1("fd%d", fdu);
1552 	TRACE1("[%s]", fdstates[fdc->state]);
1553 	TRACE1("(0x%x)", fd->flags);
1554 	untimeout(fd_turnoff, fd, fd->toffhandle);
1555 	fd->toffhandle = timeout(fd_turnoff, fd, 4 * hz);
1556 	switch (fdc->state)
1557 	{
1558 	case DEVIDLE:
1559 	case FINDWORK:	/* we have found new work */
1560 		fdc->retry = 0;
1561 		fd->skip = 0;
1562 		fdc->fd = fd;
1563 		fdc->fdu = fdu;
1564 		fdc->fdctl_wr(fdc, fd->ft->trans);
1565 		TRACE1("[0x%x->FDCTL]", fd->ft->trans);
1566 		/*
1567 		 * If the next drive has a motor startup pending, then
1568 		 * it will start up in its own good time.
1569 		 */
1570 		if(fd->flags & FD_MOTOR_WAIT) {
1571 			fdc->state = MOTORWAIT;
1572 			return (0); /* will return later */
1573 		}
1574 		/*
1575 		 * Maybe if it's not starting, it SHOULD be starting.
1576 		 */
1577 		if (!(fd->flags & FD_MOTOR))
1578 		{
1579 			fdc->state = MOTORWAIT;
1580 			fd_turnon(fd);
1581 			return (0); /* will return later */
1582 		}
1583 		else	/* at least make sure we are selected */
1584 		{
1585 			set_motor(fdc, fd->fdsu, TURNON);
1586 		}
1587 		if (fdc->flags & FDC_NEEDS_RESET) {
1588 			fdc->state = RESETCTLR;
1589 			fdc->flags &= ~FDC_NEEDS_RESET;
1590 		} else
1591 			fdc->state = DOSEEK;
1592 		return (1);	/* will return immediately */
1593 
1594 	case DOSEEK:
1595 		blknum = bp->bio_pblkno + fd->skip / fdblk;
1596 		cylinder = blknum / (fd->ft->sectrac * fd->ft->heads);
1597 		if (cylinder == fd->track)
1598 		{
1599 			fdc->state = SEEKCOMPLETE;
1600 			return (1); /* will return immediately */
1601 		}
1602 		if (fd_cmd(fdc, 3, NE7CMD_SEEK,
1603 			   fd->fdsu, cylinder * steptrac, 0))
1604 		{
1605 			/*
1606 			 * Seek command not accepted, looks like
1607 			 * the FDC went off to the Saints...
1608 			 */
1609 			fdc->retry = 6;	/* try a reset */
1610 			return(retrier(fdc));
1611 		}
1612 		fd->track = FD_NO_TRACK;
1613 		fdc->state = SEEKWAIT;
1614 		return(0);	/* will return later */
1615 
1616 	case SEEKWAIT:
1617 		/* allow heads to settle */
1618 		timeout(fd_pseudointr, fdc, hz / 16);
1619 		fdc->state = SEEKCOMPLETE;
1620 		return(0);	/* will return later */
1621 
1622 	case SEEKCOMPLETE : /* seek done, start DMA */
1623 		blknum = bp->bio_pblkno + fd->skip / fdblk;
1624 		cylinder = blknum / (fd->ft->sectrac * fd->ft->heads);
1625 
1626 		/* Make sure seek really happened. */
1627 		if(fd->track == FD_NO_TRACK) {
1628 			int descyl = cylinder * steptrac;
1629 			do {
1630 				/*
1631 				 * This might be a "ready changed" interrupt,
1632 				 * which cannot really happen since the
1633 				 * RDY pin is hardwired to + 5 volts.  This
1634 				 * generally indicates a "bouncing" intr
1635 				 * line, so do one of the following:
1636 				 *
1637 				 * When running on an enhanced FDC that is
1638 				 * known to not go stuck after responding
1639 				 * with INVALID, fetch all interrupt states
1640 				 * until seeing either an INVALID or a
1641 				 * real interrupt condition.
1642 				 *
1643 				 * When running on a dumb old NE765, give
1644 				 * up immediately.  The controller will
1645 				 * provide up to four dummy RC interrupt
1646 				 * conditions right after reset (for the
1647 				 * corresponding four drives), so this is
1648 				 * our only chance to get notice that it
1649 				 * was not the FDC that caused the interrupt.
1650 				 */
1651 				if (fd_sense_int(fdc, &st0, &cyl)
1652 				    == FD_NOT_VALID)
1653 					return (0); /* will return later */
1654 				if(fdc->fdct == FDC_NE765
1655 				   && (st0 & NE7_ST0_IC) == NE7_ST0_IC_RC)
1656 					return (0); /* hope for a real intr */
1657 			} while ((st0 & NE7_ST0_IC) == NE7_ST0_IC_RC);
1658 
1659 			if (0 == descyl) {
1660 				int failed = 0;
1661 				/*
1662 				 * seek to cyl 0 requested; make sure we are
1663 				 * really there
1664 				 */
1665 				if (fd_sense_drive_status(fdc, &st3))
1666 					failed = 1;
1667 				if ((st3 & NE7_ST3_T0) == 0) {
1668 					printf(
1669 		"fd%d: Seek to cyl 0, but not really there (ST3 = %b)\n",
1670 					       fdu, st3, NE7_ST3BITS);
1671 					failed = 1;
1672 				}
1673 
1674 				if (failed) {
1675 					if(fdc->retry < 3)
1676 						fdc->retry = 3;
1677 					return (retrier(fdc));
1678 				}
1679 			}
1680 
1681 			if (cyl != descyl) {
1682 				printf(
1683 		"fd%d: Seek to cyl %d failed; am at cyl %d (ST0 = 0x%x)\n",
1684 				       fdu, descyl, cyl, st0);
1685 				if (fdc->retry < 3)
1686 					fdc->retry = 3;
1687 				return (retrier(fdc));
1688 			}
1689 		}
1690 
1691 		fd->track = cylinder;
1692 		if (format)
1693 			fd->skip = (char *)&(finfo->fd_formb_cylno(0))
1694 			    - (char *)finfo;
1695 		if (!rdsectid && !(fdc->flags & FDC_NODMA))
1696 			isa_dmastart(idf, bp->bio_data+fd->skip,
1697 				format ? bp->bio_bcount : fdblk, fdc->dmachan);
1698 		blknum = bp->bio_pblkno + fd->skip / fdblk;
1699 		sectrac = fd->ft->sectrac;
1700 		sec = blknum %  (sectrac * fd->ft->heads);
1701 		head = sec / sectrac;
1702 		sec = sec % sectrac + 1;
1703 		if (head != 0 && fd->ft->offset_side2 != 0)
1704 			sec += fd->ft->offset_side2;
1705 		fd->hddrv = ((head&1)<<2)+fdu;
1706 
1707 		if(format || !(read || rdsectid))
1708 		{
1709 			/* make sure the drive is writable */
1710 			if(fd_sense_drive_status(fdc, &st3) != 0)
1711 			{
1712 				/* stuck controller? */
1713 				if (!(fdc->flags & FDC_NODMA))
1714 					isa_dmadone(idf,
1715 						    bp->bio_data + fd->skip,
1716 						    format ? bp->bio_bcount : fdblk,
1717 						    fdc->dmachan);
1718 				fdc->retry = 6;	/* reset the beast */
1719 				return (retrier(fdc));
1720 			}
1721 			if(st3 & NE7_ST3_WP)
1722 			{
1723 				/*
1724 				 * XXX YES! this is ugly.
1725 				 * in order to force the current operation
1726 				 * to fail, we will have to fake an FDC
1727 				 * error - all error handling is done
1728 				 * by the retrier()
1729 				 */
1730 				fdc->status[0] = NE7_ST0_IC_AT;
1731 				fdc->status[1] = NE7_ST1_NW;
1732 				fdc->status[2] = 0;
1733 				fdc->status[3] = fd->track;
1734 				fdc->status[4] = head;
1735 				fdc->status[5] = sec;
1736 				fdc->retry = 8;	/* break out immediately */
1737 				fdc->state = IOTIMEDOUT; /* not really... */
1738 				return (1); /* will return immediately */
1739 			}
1740 		}
1741 
1742 		if (format) {
1743 			ne7cmd = NE7CMD_FORMAT | mfm;
1744 			if (fdc->flags & FDC_NODMA) {
1745 				/*
1746 				 * This seems to be necessary for
1747 				 * whatever obscure reason; if we omit
1748 				 * it, we end up filling the sector ID
1749 				 * fields of the newly formatted track
1750 				 * entirely with garbage, causing
1751 				 * `wrong cylinder' errors all over
1752 				 * the place when trying to read them
1753 				 * back.
1754 				 *
1755 				 * Umpf.
1756 				 */
1757 				SET_BCDR(fdc, 1, bp->bio_bcount, 0);
1758 
1759 				(void)fdcpio(fdc,bp->bio_cmd,
1760 					bp->bio_data+fd->skip,
1761 					bp->bio_bcount);
1762 
1763 			}
1764 			/* formatting */
1765 			if(fd_cmd(fdc, 6,  ne7cmd, head << 2 | fdu,
1766 				  finfo->fd_formb_secshift,
1767 				  finfo->fd_formb_nsecs,
1768 				  finfo->fd_formb_gaplen,
1769 				  finfo->fd_formb_fillbyte, 0)) {
1770 				/* controller fell over */
1771 				if (!(fdc->flags & FDC_NODMA))
1772 					isa_dmadone(idf,
1773 						    bp->bio_data + fd->skip,
1774 						    format ? bp->bio_bcount : fdblk,
1775 						    fdc->dmachan);
1776 				fdc->retry = 6;
1777 				return (retrier(fdc));
1778 			}
1779 		} else if (rdsectid) {
1780 			ne7cmd = NE7CMD_READID | mfm;
1781 			if (fd_cmd(fdc, 2, ne7cmd, head << 2 | fdu, 0)) {
1782 				/* controller jamming */
1783 				fdc->retry = 6;
1784 				return (retrier(fdc));
1785 			}
1786 		} else {
1787 			/* read or write operation */
1788 			ne7cmd = (read ? NE7CMD_READ | NE7CMD_SK : NE7CMD_WRITE) | mfm;
1789 			if (fdc->flags & FDC_NODMA) {
1790 				/*
1791 				 * This seems to be necessary even when
1792 				 * reading data.
1793 				 */
1794 				SET_BCDR(fdc, 1, fdblk, 0);
1795 
1796 				/*
1797 				 * Perform the write pseudo-DMA before
1798 				 * the WRITE command is sent.
1799 				 */
1800 				if (!read)
1801 					(void)fdcpio(fdc,bp->bio_cmd,
1802 					    bp->bio_data+fd->skip,
1803 					    fdblk);
1804 			}
1805 			if (fd_cmd(fdc, 9,
1806 				   ne7cmd,
1807 				   head << 2 | fdu,  /* head & unit */
1808 				   fd->track,        /* track */
1809 				   head,
1810 				   sec,              /* sector + 1 */
1811 				   fd->ft->secsize,  /* sector size */
1812 				   sectrac,          /* sectors/track */
1813 				   fd->ft->gap,      /* gap size */
1814 				   fd->ft->datalen,  /* data length */
1815 				   0)) {
1816 				/* the beast is sleeping again */
1817 				if (!(fdc->flags & FDC_NODMA))
1818 					isa_dmadone(idf,
1819 						    bp->bio_data + fd->skip,
1820 						    format ? bp->bio_bcount : fdblk,
1821 						    fdc->dmachan);
1822 				fdc->retry = 6;
1823 				return (retrier(fdc));
1824 			}
1825 		}
1826 		if (!rdsectid && (fdc->flags & FDC_NODMA))
1827 			/*
1828 			 * If this is a read, then simply await interrupt
1829 			 * before performing PIO.
1830 			 */
1831 			if (read && !fdcpio(fdc,bp->bio_cmd,
1832 			    bp->bio_data+fd->skip,fdblk)) {
1833 				fd->tohandle = timeout(fd_iotimeout, fdc, hz);
1834 				return(0);      /* will return later */
1835 			}
1836 
1837 		/*
1838 		 * Write (or format) operation will fall through and
1839 		 * await completion interrupt.
1840 		 */
1841 		fdc->state = IOCOMPLETE;
1842 		fd->tohandle = timeout(fd_iotimeout, fdc, hz);
1843 		return (0);	/* will return later */
1844 
1845 	case PIOREAD:
1846 		/*
1847 		 * Actually perform the PIO read.  The IOCOMPLETE case
1848 		 * removes the timeout for us.
1849 		 */
1850 		(void)fdcpio(fdc,bp->bio_cmd,bp->bio_data+fd->skip,fdblk);
1851 		fdc->state = IOCOMPLETE;
1852 		/* FALLTHROUGH */
1853 	case IOCOMPLETE: /* IO done, post-analyze */
1854 		untimeout(fd_iotimeout, fdc, fd->tohandle);
1855 
1856 		if (fd_read_status(fdc)) {
1857 			if (!rdsectid && !(fdc->flags & FDC_NODMA))
1858 				isa_dmadone(idf, bp->bio_data + fd->skip,
1859 					    format ? bp->bio_bcount : fdblk,
1860 					    fdc->dmachan);
1861 			if (fdc->retry < 6)
1862 				fdc->retry = 6;	/* force a reset */
1863 			return (retrier(fdc));
1864   		}
1865 
1866 		fdc->state = IOTIMEDOUT;
1867 
1868 		/* FALLTHROUGH */
1869 	case IOTIMEDOUT:
1870 		if (!rdsectid && !(fdc->flags & FDC_NODMA))
1871 			isa_dmadone(idf, bp->bio_data + fd->skip,
1872 				format ? bp->bio_bcount : fdblk, fdc->dmachan);
1873 		if (fdc->status[0] & NE7_ST0_IC) {
1874                         if ((fdc->status[0] & NE7_ST0_IC) == NE7_ST0_IC_AT
1875 			    && fdc->status[1] & NE7_ST1_OR) {
1876                                 /*
1877 				 * DMA overrun. Someone hogged the bus and
1878 				 * didn't release it in time for the next
1879 				 * FDC transfer.
1880 				 *
1881 				 * We normally restart this without bumping
1882 				 * the retry counter.  However, in case
1883 				 * something is seriously messed up (like
1884 				 * broken hardware), we rather limit the
1885 				 * number of retries so the IO operation
1886 				 * doesn't block indefinately.
1887 				 */
1888 				if (fdc->dma_overruns++ < FDC_DMAOV_MAX) {
1889 					fdc->state = SEEKCOMPLETE;
1890 					return (1);/* will return immediately */
1891 				} /* else fall through */
1892                         }
1893 			if((fdc->status[0] & NE7_ST0_IC) == NE7_ST0_IC_IV
1894 				&& fdc->retry < 6)
1895 				fdc->retry = 6;	/* force a reset */
1896 			else if((fdc->status[0] & NE7_ST0_IC) == NE7_ST0_IC_AT
1897 				&& fdc->status[2] & NE7_ST2_WC
1898 				&& fdc->retry < 3)
1899 				fdc->retry = 3;	/* force recalibrate */
1900 			return (retrier(fdc));
1901 		}
1902 		/* All OK */
1903 		if (rdsectid) {
1904 			/* copy out ID field contents */
1905 			idp = (struct fdc_readid *)bp->bio_data;
1906 			idp->cyl = fdc->status[3];
1907 			idp->head = fdc->status[4];
1908 			idp->sec = fdc->status[5];
1909 			idp->secshift = fdc->status[6];
1910 		}
1911 		/* Operation successful, retry DMA overruns again next time. */
1912 		fdc->dma_overruns = 0;
1913 		fd->skip += fdblk;
1914 		if (!rdsectid && !format && fd->skip < bp->bio_bcount) {
1915 			/* set up next transfer */
1916 			fdc->state = DOSEEK;
1917 		} else {
1918 			/* ALL DONE */
1919 			fd->skip = 0;
1920 			bp->bio_resid = 0;
1921 			fdc->bp = NULL;
1922 			device_unbusy(fd->dev);
1923 			biofinish(bp, fd->device_stats, 0);
1924 			fdc->fd = (fd_p) 0;
1925 			fdc->fdu = -1;
1926 			fdc->state = FINDWORK;
1927 		}
1928 		return (1);	/* will return immediately */
1929 
1930 	case RESETCTLR:
1931 		fdc_reset(fdc);
1932 		fdc->retry++;
1933 		fdc->state = RESETCOMPLETE;
1934 		return (0);	/* will return later */
1935 
1936 	case RESETCOMPLETE:
1937 		/*
1938 		 * Discard all the results from the reset so that they
1939 		 * can't cause an unexpected interrupt later.
1940 		 */
1941 		for (i = 0; i < 4; i++)
1942 			(void)fd_sense_int(fdc, &st0, &cyl);
1943 		fdc->state = STARTRECAL;
1944 		/* FALLTHROUGH */
1945 	case STARTRECAL:
1946 		if(fd_cmd(fdc, 2, NE7CMD_RECAL, fdu, 0)) {
1947 			/* arrgl */
1948 			fdc->retry = 6;
1949 			return (retrier(fdc));
1950 		}
1951 		fdc->state = RECALWAIT;
1952 		return (0);	/* will return later */
1953 
1954 	case RECALWAIT:
1955 		/* allow heads to settle */
1956 		timeout(fd_pseudointr, fdc, hz / 8);
1957 		fdc->state = RECALCOMPLETE;
1958 		return (0);	/* will return later */
1959 
1960 	case RECALCOMPLETE:
1961 		do {
1962 			/*
1963 			 * See SEEKCOMPLETE for a comment on this:
1964 			 */
1965 			if (fd_sense_int(fdc, &st0, &cyl) == FD_NOT_VALID)
1966 				return (0); /* will return later */
1967 			if(fdc->fdct == FDC_NE765
1968 			   && (st0 & NE7_ST0_IC) == NE7_ST0_IC_RC)
1969 				return (0); /* hope for a real intr */
1970 		} while ((st0 & NE7_ST0_IC) == NE7_ST0_IC_RC);
1971 		if ((st0 & NE7_ST0_IC) != NE7_ST0_IC_NT || cyl != 0)
1972 		{
1973 			if(fdc->retry > 3)
1974 				/*
1975 				 * A recalibrate from beyond cylinder 77
1976 				 * will "fail" due to the FDC limitations;
1977 				 * since people used to complain much about
1978 				 * the failure message, try not logging
1979 				 * this one if it seems to be the first
1980 				 * time in a line.
1981 				 */
1982 				printf("fd%d: recal failed ST0 %b cyl %d\n",
1983 				       fdu, st0, NE7_ST0BITS, cyl);
1984 			if(fdc->retry < 3) fdc->retry = 3;
1985 			return (retrier(fdc));
1986 		}
1987 		fd->track = 0;
1988 		/* Seek (probably) necessary */
1989 		fdc->state = DOSEEK;
1990 		return (1);	/* will return immediately */
1991 
1992 	case MOTORWAIT:
1993 		if(fd->flags & FD_MOTOR_WAIT)
1994 		{
1995 			return (0); /* time's not up yet */
1996 		}
1997 		if (fdc->flags & FDC_NEEDS_RESET) {
1998 			fdc->state = RESETCTLR;
1999 			fdc->flags &= ~FDC_NEEDS_RESET;
2000 		} else
2001 			fdc->state = DOSEEK;
2002 		return (1);	/* will return immediately */
2003 
2004 	default:
2005 		device_printf(fdc->fdc_dev, "unexpected FD int->");
2006 		if (fd_read_status(fdc) == 0)
2007 			printf("FDC status :%x %x %x %x %x %x %x   ",
2008 			       fdc->status[0],
2009 			       fdc->status[1],
2010 			       fdc->status[2],
2011 			       fdc->status[3],
2012 			       fdc->status[4],
2013 			       fdc->status[5],
2014 			       fdc->status[6] );
2015 		else
2016 			printf("No status available   ");
2017 		if (fd_sense_int(fdc, &st0, &cyl) != 0)
2018 		{
2019 			printf("[controller is dead now]\n");
2020 			return (0); /* will return later */
2021 		}
2022 		printf("ST0 = %x, PCN = %x\n", st0, cyl);
2023 		return (0);	/* will return later */
2024 	}
2025 	/* noone should ever get here */
2026 }
2027 
2028 static int
2029 retrier(struct fdc_data *fdc)
2030 {
2031 	struct bio *bp;
2032 	struct fd_data *fd;
2033 	int fdu;
2034 
2035 	bp = fdc->bp;
2036 
2037 	/* XXX shouldn't this be cached somewhere?  */
2038 	fd = bp->bio_dev->si_drv1;
2039 	fdu = fd->fdu;
2040 	if (fd->options & FDOPT_NORETRY)
2041 		goto fail;
2042 
2043 	switch (fdc->retry) {
2044 	case 0: case 1: case 2:
2045 		fdc->state = SEEKCOMPLETE;
2046 		break;
2047 	case 3: case 4: case 5:
2048 		fdc->state = STARTRECAL;
2049 		break;
2050 	case 6:
2051 		fdc->state = RESETCTLR;
2052 		break;
2053 	case 7:
2054 		break;
2055 	default:
2056 	fail:
2057 		if ((fd->options & FDOPT_NOERRLOG) == 0) {
2058 			disk_err(bp, "hard error",
2059 			    fdc->fd->skip / DEV_BSIZE, 0);
2060 			if (fdc->flags & FDC_STAT_VALID) {
2061 				printf(
2062 				" (ST0 %b ST1 %b ST2 %b cyl %u hd %u sec %u)\n",
2063 				       fdc->status[0], NE7_ST0BITS,
2064 				       fdc->status[1], NE7_ST1BITS,
2065 				       fdc->status[2], NE7_ST2BITS,
2066 				       fdc->status[3], fdc->status[4],
2067 				       fdc->status[5]);
2068 			}
2069 			else
2070 				printf(" (No status)\n");
2071 		}
2072 		if ((fd->options & FDOPT_NOERROR) == 0) {
2073 			bp->bio_flags |= BIO_ERROR;
2074 			bp->bio_error = EIO;
2075 			bp->bio_resid = bp->bio_bcount - fdc->fd->skip;
2076 		} else
2077 			bp->bio_resid = 0;
2078 		fdc->bp = NULL;
2079 		fdc->fd->skip = 0;
2080 		device_unbusy(fd->dev);
2081 		biofinish(bp, fdc->fd->device_stats, 0);
2082 		fdc->state = FINDWORK;
2083 		fdc->flags |= FDC_NEEDS_RESET;
2084 		fdc->fd = (fd_p) 0;
2085 		fdc->fdu = -1;
2086 		return (1);
2087 	}
2088 	fdc->retry++;
2089 	return (1);
2090 }
2091 
2092 static void
2093 fdbiodone(struct bio *bp)
2094 {
2095 	wakeup(bp);
2096 }
2097 
2098 static int
2099 fdmisccmd(struct cdev *dev, u_int cmd, void *data)
2100 {
2101  	fdu_t fdu;
2102  	fd_p fd;
2103 	struct bio *bp;
2104 	struct fd_formb *finfo;
2105 	struct fdc_readid *idfield;
2106 	size_t fdblk;
2107 	int error;
2108 
2109 	fd = dev->si_drv1;
2110  	fdu = fd->fdu;
2111 	fdblk = 128 << fd->ft->secsize;
2112 	finfo = (struct fd_formb *)data;
2113 	idfield = (struct fdc_readid *)data;
2114 
2115 	bp = malloc(sizeof(struct bio), M_TEMP, M_WAITOK | M_ZERO);
2116 
2117 	/*
2118 	 * Set up a bio request for fdstrategy().  bio_offset is faked
2119 	 * so that fdstrategy() will seek to the the requested
2120 	 * cylinder, and use the desired head.
2121 	 */
2122 	bp->bio_cmd = cmd;
2123 	if (cmd == FDBIO_FORMAT) {
2124 		bp->bio_offset =
2125 		    (finfo->cyl * (fd->ft->sectrac * fd->ft->heads) +
2126 		     finfo->head * fd->ft->sectrac) * fdblk;
2127 		bp->bio_bcount = sizeof(struct fd_idfield_data) *
2128 		    finfo->fd_formb_nsecs;
2129 	} else if (cmd == FDBIO_RDSECTID) {
2130 		bp->bio_offset =
2131 		    (idfield->cyl * (fd->ft->sectrac * fd->ft->heads) +
2132 		     idfield->head * fd->ft->sectrac) * fdblk;
2133 		bp->bio_bcount = sizeof(struct fdc_readid);
2134 	} else
2135 		panic("wrong cmd in fdmisccmd()");
2136 	bp->bio_data = data;
2137 	bp->bio_dev = dev;
2138 	bp->bio_done = fdbiodone;
2139 	bp->bio_flags = 0;
2140 
2141 	/* Now run the command. */
2142 	fdstrategy(bp);
2143 	error = biowait(bp, "fdcmd");
2144 
2145 	free(bp, M_TEMP);
2146 	return (error);
2147 }
2148 
2149 static int
2150 fdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
2151 {
2152  	fdu_t fdu;
2153  	fd_p fd;
2154 	struct fdc_status *fsp;
2155 	struct fdc_readid *rid;
2156 	int error;
2157 
2158  	fd = dev->si_drv1;
2159  	fdu = fd->fdu;
2160 
2161 	/*
2162 	 * First, handle everything that could be done with
2163 	 * FD_NONBLOCK still being set.
2164 	 */
2165 	switch (cmd) {
2166 
2167 	case DIOCGMEDIASIZE:
2168 		if (fd->ft == 0)
2169 			return ((fd->flags & FD_NONBLOCK) ? EAGAIN : ENXIO);
2170 		*(off_t *)addr = (128 << (fd->ft->secsize)) * fd->ft->size;
2171 		return (0);
2172 
2173 	case DIOCGSECTORSIZE:
2174 		if (fd->ft == 0)
2175 			return ((fd->flags & FD_NONBLOCK) ? EAGAIN : ENXIO);
2176 		*(u_int *)addr = 128 << (fd->ft->secsize);
2177 		return (0);
2178 
2179 	case FIONBIO:
2180 		if (*(int *)addr != 0)
2181 			fd->flags |= FD_NONBLOCK;
2182 		else {
2183 			if (fd->ft == 0) {
2184 				/*
2185 				 * No drive type has been selected yet,
2186 				 * cannot turn FNONBLOCK off.
2187 				 */
2188 				return (EINVAL);
2189 			}
2190 			fd->flags &= ~FD_NONBLOCK;
2191 		}
2192 		return (0);
2193 
2194 	case FIOASYNC:
2195 		/* keep the generic fcntl() code happy */
2196 		return (0);
2197 
2198 	case FD_GTYPE:                  /* get drive type */
2199 		if (fd->ft == 0)
2200 			/* no type known yet, return the native type */
2201 			*(struct fd_type *)addr = fd_native_types[fd->type];
2202 		else
2203 			*(struct fd_type *)addr = *fd->ft;
2204 		return (0);
2205 
2206 	case FD_STYPE:                  /* set drive type */
2207 		/*
2208 		 * Allow setting drive type temporarily iff
2209 		 * currently unset.  Used for fdformat so any
2210 		 * user can set it, and then start formatting.
2211 		 */
2212 		if (fd->ft)
2213 			return (EINVAL); /* already set */
2214 		fd->fts[0] = *(struct fd_type *)addr;
2215 		fd->ft = &fd->fts[0];
2216 		fd->flags |= FD_UA;
2217 		return (0);
2218 
2219 	case FD_GOPTS:			/* get drive options */
2220 		*(int *)addr = fd->options + FDOPT_AUTOSEL;
2221 		return (0);
2222 
2223 	case FD_SOPTS:			/* set drive options */
2224 		fd->options = *(int *)addr & ~FDOPT_AUTOSEL;
2225 		return (0);
2226 
2227 #ifdef FDC_DEBUG
2228 	case FD_DEBUG:
2229 		if ((fd_debug != 0) != (*(int *)addr != 0)) {
2230 			fd_debug = (*(int *)addr != 0);
2231 			printf("fd%d: debugging turned %s\n",
2232 			    fd->fdu, fd_debug ? "on" : "off");
2233 		}
2234 		return (0);
2235 #endif
2236 
2237 	case FD_CLRERR:
2238 		if (suser(td) != 0)
2239 			return (EPERM);
2240 		fd->fdc->fdc_errs = 0;
2241 		return (0);
2242 
2243 	case FD_GSTAT:
2244 		fsp = (struct fdc_status *)addr;
2245 		if ((fd->fdc->flags & FDC_STAT_VALID) == 0)
2246 			return (EINVAL);
2247 		memcpy(fsp->status, fd->fdc->status, 7 * sizeof(u_int));
2248 		return (0);
2249 
2250 	case FD_GDTYPE:
2251 		*(enum fd_drivetype *)addr = fd->type;
2252 		return (0);
2253 	}
2254 
2255 	/*
2256 	 * Now handle everything else.  Make sure we have a valid
2257 	 * drive type.
2258 	 */
2259 	if (fd->flags & FD_NONBLOCK)
2260 		return (EAGAIN);
2261 	if (fd->ft == 0)
2262 		return (ENXIO);
2263 	error = 0;
2264 
2265 	switch (cmd) {
2266 
2267 	case FD_FORM:
2268 		if ((flag & FWRITE) == 0)
2269 			return (EBADF);	/* must be opened for writing */
2270 		if (((struct fd_formb *)addr)->format_version !=
2271 		    FD_FORMAT_VERSION)
2272 			return (EINVAL); /* wrong version of formatting prog */
2273 		error = fdmisccmd(dev, FDBIO_FORMAT, addr);
2274 		break;
2275 
2276 	case FD_GTYPE:                  /* get drive type */
2277 		*(struct fd_type *)addr = *fd->ft;
2278 		break;
2279 
2280 	case FD_STYPE:                  /* set drive type */
2281 		/* this is considered harmful; only allow for superuser */
2282 		if (suser(td) != 0)
2283 			return (EPERM);
2284 		*fd->ft = *(struct fd_type *)addr;
2285 		break;
2286 
2287 	case FD_GOPTS:			/* get drive options */
2288 		*(int *)addr = fd->options;
2289 		break;
2290 
2291 	case FD_SOPTS:			/* set drive options */
2292 		fd->options = *(int *)addr;
2293 		break;
2294 
2295 #ifdef FDC_DEBUG
2296 	case FD_DEBUG:
2297 		if ((fd_debug != 0) != (*(int *)addr != 0)) {
2298 			fd_debug = (*(int *)addr != 0);
2299 			printf("fd%d: debugging turned %s\n",
2300 			    fd->fdu, fd_debug ? "on" : "off");
2301 		}
2302 		break;
2303 #endif
2304 
2305 	case FD_CLRERR:
2306 		if (suser(td) != 0)
2307 			return (EPERM);
2308 		fd->fdc->fdc_errs = 0;
2309 		break;
2310 
2311 	case FD_GSTAT:
2312 		fsp = (struct fdc_status *)addr;
2313 		if ((fd->fdc->flags & FDC_STAT_VALID) == 0)
2314 			return (EINVAL);
2315 		memcpy(fsp->status, fd->fdc->status, 7 * sizeof(u_int));
2316 		break;
2317 
2318 	case FD_READID:
2319 		rid = (struct fdc_readid *)addr;
2320 		if (rid->cyl > MAX_CYLINDER || rid->head > MAX_HEAD)
2321 			return (EINVAL);
2322 		error = fdmisccmd(dev, FDBIO_RDSECTID, addr);
2323 		break;
2324 
2325 	default:
2326 		error = ENOTTY;
2327 		break;
2328 	}
2329 	return (error);
2330 }
2331