xref: /netbsd-src/sys/arch/hp300/dev/mt.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: mt.c,v 1.52 2014/03/24 19:42:58 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996, 1997 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1992, The University of Utah and
34  * the Computer Systems Laboratory at the University of Utah (CSL).
35  * All rights reserved.
36  *
37  * Permission to use, copy, modify and distribute this software is hereby
38  * granted provided that (1) source code retains these copyright, permission,
39  * and disclaimer notices, and (2) redistributions including binaries
40  * reproduce the notices in supporting documentation, and (3) all advertising
41  * materials mentioning features or use of this software display the following
42  * acknowledgement: ``This product includes software developed by the
43  * Computer Systems Laboratory at the University of Utah.''
44  *
45  * THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS
46  * IS" CONDITION.  THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF
47  * ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
48  *
49  * CSL requests users of this software to return to csl-dist@cs.utah.edu any
50  * improvements that they make and grant CSL redistribution rights.
51  *
52  *	Utah $Hdr: mt.c 1.8 95/09/12$
53  */
54 /*	@(#)mt.c	3.9	90/07/10	mt Xinu
55  *
56  * Magnetic tape driver (7974a, 7978a/b, 7979a, 7980a, 7980xc)
57  * Original version contributed by Mt. Xinu.
58  * Modified for 4.4BSD by Mark Davies and Andrew Vignaux, Department of
59  * Computer Science, Victoria University of Wellington
60  */
61 
62 #include <sys/cdefs.h>
63 __KERNEL_RCSID(0, "$NetBSD: mt.c,v 1.52 2014/03/24 19:42:58 christos Exp $");
64 
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/callout.h>
68 #include <sys/buf.h>
69 #include <sys/bufq.h>
70 #include <sys/ioctl.h>
71 #include <sys/mtio.h>
72 #include <sys/file.h>
73 #include <sys/proc.h>
74 #include <sys/errno.h>
75 #include <sys/syslog.h>
76 #include <sys/tty.h>
77 #include <sys/kernel.h>
78 #include <sys/tprintf.h>
79 #include <sys/device.h>
80 #include <sys/conf.h>
81 
82 #include <hp300/dev/hpibvar.h>
83 
84 #include <hp300/dev/mtreg.h>
85 
86 #include "ioconf.h"
87 
88 static const struct mtinfo {
89 	u_short	hwid;
90 	const char *desc;
91 } mtinfo[] = {
92 	{ MT7978ID,	"7978"	},
93 	{ MT7979AID,	"7979A"	},
94 	{ MT7980ID,	"7980"	},
95 	{ MT7974AID,	"7974A"	},
96 };
97 static const int nmtinfo = sizeof(mtinfo) / sizeof(mtinfo[0]);
98 
99 struct	mt_softc {
100 	device_t sc_dev;
101 	struct	callout sc_start_ch;
102 	struct	callout sc_intr_ch;
103 	int	sc_hpibno;	/* logical HPIB this slave it attached to */
104 	int	sc_slave;	/* HPIB slave address (0-6) */
105 	short	sc_flags;	/* see below */
106 	u_char	sc_lastdsj;	/* place for DSJ in mtreaddsj() */
107 	u_char	sc_lastecmd;	/* place for End Command in mtreaddsj() */
108 	short	sc_recvtimeo;	/* count of hpibsend timeouts to prevent hang */
109 	short	sc_statindex;	/* index for next sc_stat when MTF_STATTIMEO */
110 	struct	mt_stat sc_stat;/* status bytes last read from device */
111 	short	sc_density;	/* current density of tape (mtio.h format) */
112 	short	sc_type;	/* tape drive model (hardware IDs) */
113 	struct	hpibqueue sc_hq; /* HPIB device queue member */
114 	tpr_t	sc_ttyp;
115 	struct bufq_state *sc_tab;/* buf queue */
116 	int	sc_active;
117 };
118 
119 #ifdef DEBUG
120 int	mtdebug = 0;
121 #define	dlog	if (mtdebug) log
122 #else
123 #define	dlog	if (0) log
124 #endif
125 
126 #define	UNIT(x)		(minor(x) & 3)
127 
128 #define B_CMD		B_DEVPRIVATE	/* command buf instead of data */
129 #define	b_cmd		b_blkno		/* blkno holds cmd when B_CMD */
130 
131 static int	mtmatch(device_t, cfdata_t, void *);
132 static void	mtattach(device_t, device_t, void *);
133 
134 CFATTACH_DECL_NEW(mt, sizeof(struct mt_softc),
135     mtmatch, mtattach, NULL, NULL);
136 
137 static dev_type_open(mtopen);
138 static dev_type_close(mtclose);
139 static dev_type_read(mtread);
140 static dev_type_write(mtwrite);
141 static dev_type_ioctl(mtioctl);
142 static dev_type_strategy(mtstrategy);
143 
144 const struct bdevsw mt_bdevsw = {
145 	.d_open = mtopen,
146 	.d_close = mtclose,
147 	.d_strategy = mtstrategy,
148 	.d_ioctl = mtioctl,
149 	.d_dump = nodump,
150 	.d_psize = nosize,
151 	.d_flag = D_TAPE
152 };
153 
154 const struct cdevsw mt_cdevsw = {
155 	.d_open = mtopen,
156 	.d_close = mtclose,
157 	.d_read = mtread,
158 	.d_write = mtwrite,
159 	.d_ioctl = mtioctl,
160 	.d_stop = nostop,
161 	.d_tty = notty,
162 	.d_poll = nopoll,
163 	.d_mmap = nommap,
164 	.d_kqfilter = nokqfilter,
165 	.d_flag = D_TAPE
166 };
167 
168 static int	mtident(struct mt_softc *, struct hpibbus_attach_args *);
169 static void	mtustart(struct mt_softc *);
170 static int	mtreaddsj(struct mt_softc *, int);
171 static int	mtcommand(dev_t, int, int);
172 static void	spl_mtintr(void *);
173 static void	spl_mtstart(void *);
174 
175 static void	mtstart(void *);
176 static void	mtgo(void *);
177 static void	mtintr(void *);
178 
179 static int
180 mtmatch(device_t parent, cfdata_t cf, void *aux)
181 {
182 	struct hpibbus_attach_args *ha = aux;
183 
184 	return mtident(NULL, ha);
185 }
186 
187 static void
188 mtattach(device_t parent, device_t self, void *aux)
189 {
190 	struct mt_softc *sc = device_private(self);
191 	struct hpibbus_attach_args *ha = aux;
192 	int hpibno, slave;
193 
194 	sc->sc_dev = self;
195 	if (mtident(sc, ha) == 0) {
196 		aprint_error(": impossible!\n");
197 		return;
198 	}
199 
200 	hpibno = device_unit(parent);
201 	slave = ha->ha_slave;
202 
203 	bufq_alloc(&sc->sc_tab, "fcfs", 0);
204 	callout_init(&sc->sc_start_ch, 0);
205 	callout_init(&sc->sc_intr_ch, 0);
206 
207 	sc->sc_hpibno = hpibno;
208 	sc->sc_slave = slave;
209 	sc->sc_flags = MTF_EXISTS;
210 
211 	/* Initialize hpib job queue entry. */
212 	sc->sc_hq.hq_softc = sc;
213 	sc->sc_hq.hq_slave = sc->sc_slave;
214 	sc->sc_hq.hq_start = mtstart;
215 	sc->sc_hq.hq_go = mtgo;
216 	sc->sc_hq.hq_intr = mtintr;
217 }
218 
219 static int
220 mtident(struct mt_softc *sc, struct hpibbus_attach_args *ha)
221 {
222 	int i;
223 
224 	for (i = 0; i < nmtinfo; i++) {
225 		if (ha->ha_id == mtinfo[i].hwid) {
226 			if (sc != NULL) {
227 				sc->sc_type = mtinfo[i].hwid;
228 				aprint_normal(": %s tape\n", mtinfo[i].desc);
229 			}
230 			return 1;
231 		}
232 	}
233 	return 0;
234 }
235 
236 /*
237  * Perform a read of "Device Status Jump" register and update the
238  * status if necessary.  If status is read, the given "ecmd" is also
239  * performed, unless "ecmd" is zero.  Returns DSJ value, -1 on failure
240  * and -2 on "temporary" failure.
241  */
242 static int
243 mtreaddsj(struct mt_softc *sc, int ecmd)
244 {
245 	int retval;
246 
247 	if (sc->sc_flags & MTF_STATTIMEO)
248 		goto getstats;
249 	retval = hpibrecv(sc->sc_hpibno,
250 	    (sc->sc_flags & MTF_DSJTIMEO) ? -1 : sc->sc_slave,
251 	    MTT_DSJ, &(sc->sc_lastdsj), 1);
252 	sc->sc_flags &= ~MTF_DSJTIMEO;
253 	if (retval != 1) {
254 		dlog(LOG_DEBUG, "%s can't hpibrecv DSJ",
255 		    device_xname(sc->sc_dev));
256 		if (sc->sc_recvtimeo == 0)
257 			sc->sc_recvtimeo = hz;
258 		if (--sc->sc_recvtimeo == 0)
259 			return -1;
260 		if (retval == 0)
261 			sc->sc_flags |= MTF_DSJTIMEO;
262 		return -2;
263 	}
264 	sc->sc_recvtimeo = 0;
265 	sc->sc_statindex = 0;
266 	dlog(LOG_DEBUG, "%s readdsj: 0x%x", device_xname(sc->sc_dev),
267 	    sc->sc_lastdsj);
268 	sc->sc_lastecmd = ecmd;
269 	switch (sc->sc_lastdsj) {
270 	    case 0:
271 		if (ecmd & MTE_DSJ_FORCE)
272 			break;
273 		return 0;
274 
275 	    case 2:
276 		sc->sc_lastecmd = MTE_COMPLETE;
277 	    case 1:
278 		break;
279 
280 	    default:
281 		log(LOG_ERR, "%s readdsj: DSJ 0x%x\n", device_xname(sc->sc_dev),
282 		    sc->sc_lastdsj);
283 		return -1;
284 	}
285  getstats:
286 	retval = hpibrecv(sc->sc_hpibno,
287 	    (sc->sc_flags & MTF_STATCONT) ? -1 : sc->sc_slave,
288 	    MTT_STAT, ((char *)&(sc->sc_stat)) + sc->sc_statindex,
289 	    sizeof(sc->sc_stat) - sc->sc_statindex);
290 	sc->sc_flags &= ~(MTF_STATTIMEO | MTF_STATCONT);
291 	if (retval != sizeof(sc->sc_stat) - sc->sc_statindex) {
292 		if (sc->sc_recvtimeo == 0)
293 			sc->sc_recvtimeo = hz;
294 		if (--sc->sc_recvtimeo != 0) {
295 			if (retval >= 0) {
296 				sc->sc_statindex += retval;
297 				sc->sc_flags |= MTF_STATCONT;
298 			}
299 			sc->sc_flags |= MTF_STATTIMEO;
300 			return -2;
301 		}
302 		log(LOG_ERR, "%s readdsj: can't read status",
303 		    device_xname(sc->sc_dev));
304 		return -1;
305 	}
306 	sc->sc_recvtimeo = 0;
307 	sc->sc_statindex = 0;
308 	dlog(LOG_DEBUG, "%s readdsj: status is %x %x %x %x %x %x",
309 	    device_xname(sc->sc_dev),
310 	    sc->sc_stat1, sc->sc_stat2, sc->sc_stat3,
311 	    sc->sc_stat4, sc->sc_stat5, sc->sc_stat6);
312 	if (sc->sc_lastecmd)
313 		(void) hpibsend(sc->sc_hpibno, sc->sc_slave,
314 		    MTL_ECMD, &(sc->sc_lastecmd), 1);
315 	return (int)sc->sc_lastdsj;
316 }
317 
318 static int
319 mtopen(dev_t dev, int flag, int mode, struct lwp *l)
320 {
321 	struct mt_softc *sc;
322 	int req_den;
323 	int error;
324 
325 	sc = device_lookup_private(&mt_cd, UNIT(dev));
326 	if (sc == NULL)
327 		return ENXIO;
328 
329 	if ((sc->sc_flags & MTF_EXISTS) == 0)
330 		return ENXIO;
331 
332 	dlog(LOG_DEBUG, "%s open: flags 0x%x", device_xname(sc->sc_dev),
333 	    sc->sc_flags);
334 	if (sc->sc_flags & MTF_OPEN)
335 		return EBUSY;
336 	sc->sc_flags |= MTF_OPEN;
337 	sc->sc_ttyp = tprintf_open(l->l_proc);
338 	if ((sc->sc_flags & MTF_ALIVE) == 0) {
339 		error = mtcommand(dev, MTRESET, 0);
340 		if (error != 0 || (sc->sc_flags & MTF_ALIVE) == 0)
341 			goto errout;
342 		if ((sc->sc_stat1 & (SR1_BOT | SR1_ONLINE)) == SR1_ONLINE)
343 			(void) mtcommand(dev, MTREW, 0);
344 	}
345 	for (;;) {
346 		if ((error = mtcommand(dev, MTNOP, 0)) != 0)
347 			goto errout;
348 		if (!(sc->sc_flags & MTF_REW))
349 			break;
350 		error = kpause("mt", true, hz, NULL);
351 		if (error != 0 && error != EWOULDBLOCK) {
352 			error = EINTR;
353 			goto errout;
354 		}
355 	}
356 	if ((flag & FWRITE) && (sc->sc_stat1 & SR1_RO)) {
357 		error = EROFS;
358 		goto errout;
359 	}
360 	if (!(sc->sc_stat1 & SR1_ONLINE)) {
361 		uprintf("%s: not online\n", device_xname(sc->sc_dev));
362 		error = EIO;
363 		goto errout;
364 	}
365 	/*
366 	 * Select density:
367 	 *  - find out what density the drive is set to
368 	 *	(i.e. the density of the current tape)
369 	 *  - if we are going to write
370 	 *    - if we're not at the beginning of the tape
371 	 *      - complain if we want to change densities
372 	 *    - otherwise, select the mtcommand to set the density
373 	 *
374 	 * If the drive doesn't support it then don't change the recorded
375 	 * density.
376 	 *
377 	 * The original MOREbsd code had these additional conditions
378 	 * for the mid-tape change
379 	 *
380 	 *	req_den != T_BADBPI &&
381 	 *	sc->sc_density != T_6250BPI
382 	 *
383 	 * which suggests that it would be possible to write multiple
384 	 * densities if req_den == T_BAD_BPI or the current tape
385 	 * density was 6250.  Testing of our 7980 suggests that the
386 	 * device cannot change densities mid-tape.
387 	 *
388 	 * ajv@comp.vuw.ac.nz
389 	 */
390 	sc->sc_density = (sc->sc_stat2 & SR2_6250) ? T_6250BPI : (
391 			 (sc->sc_stat3 & SR3_1600) ? T_1600BPI : (
392 			 (sc->sc_stat3 & SR3_800) ? T_800BPI : -1));
393 	req_den = (dev & T_DENSEL);
394 
395 	if (flag & FWRITE) {
396 		if (!(sc->sc_stat1 & SR1_BOT)) {
397 			if (sc->sc_density != req_den) {
398 				uprintf("%s: can't change density mid-tape\n",
399 				    device_xname(sc->sc_dev));
400 				error = EIO;
401 				goto errout;
402 			}
403 		}
404 		else {
405 			int mtset_density =
406 			    (req_den == T_800BPI  ? MTSET800BPI : (
407 			     req_den == T_1600BPI ? MTSET1600BPI : (
408 			     req_den == T_6250BPI ? MTSET6250BPI : (
409 			     sc->sc_type == MT7980ID
410 						  ? MTSET6250DC
411 						  : MTSET6250BPI))));
412 			if (mtcommand(dev, mtset_density, 0) == 0)
413 				sc->sc_density = req_den;
414 		}
415 	}
416 	return 0;
417 errout:
418 	sc->sc_flags &= ~MTF_OPEN;
419 	return error;
420 }
421 
422 static int
423 mtclose(dev_t dev, int flag, int fmt, struct lwp *l)
424 {
425 	struct mt_softc *sc = device_lookup_private(&mt_cd,UNIT(dev));
426 
427 	if (sc->sc_flags & MTF_WRT) {
428 		(void) mtcommand(dev, MTWEOF, 2);
429 		(void) mtcommand(dev, MTBSF, 0);
430 	}
431 	if ((minor(dev) & T_NOREWIND) == 0)
432 		(void) mtcommand(dev, MTREW, 0);
433 	sc->sc_flags &= ~MTF_OPEN;
434 	tprintf_close(sc->sc_ttyp);
435 	return 0;
436 }
437 
438 static int
439 mtcommand(dev_t dev, int cmd, int cnt)
440 {
441 	int error = 0;
442 	buf_t *bp;
443 
444 	bp = getiobuf(NULL, true);
445 	bp->b_cmd = cmd;
446 	bp->b_dev = dev;
447 	do {
448 		bp->b_cflags = BC_BUSY;
449 		bp->b_flags = B_CMD;
450 		bp->b_oflags = 0;
451 		mtstrategy(bp);
452 		biowait(bp);
453 		if (bp->b_error != 0) {
454 			error = bp->b_error;
455 			break;
456 		}
457 	} while (--cnt > 0);
458 	putiobuf(bp);
459 
460 	return error;
461 }
462 
463 /*
464  * Only thing to check here is for legal record lengths (writes only).
465  */
466 static void
467 mtstrategy(struct buf *bp)
468 {
469 	struct mt_softc *sc;
470 	int s;
471 
472 	sc = device_lookup_private(&mt_cd,UNIT(bp->b_dev));
473 	dlog(LOG_DEBUG, "%s strategy", device_xname(sc->sc_dev));
474 	if ((bp->b_flags & (B_CMD | B_READ)) == 0) {
475 #define WRITE_BITS_IGNORED	8
476 #if 0
477 		if (bp->b_bcount & ((1 << WRITE_BITS_IGNORED) - 1)) {
478 			tprintf(sc->sc_ttyp,
479 			    "%s: write record must be multiple of %d\n",
480 			    device_xname(sc->sc_dev), 1 << WRITE_BITS_IGNORED);
481 			goto error;
482 		}
483 #endif
484 		s = 16 * 1024;
485 		if (sc->sc_stat2 & SR2_LONGREC) {
486 			switch (sc->sc_density) {
487 			    case T_1600BPI:
488 				s = 32 * 1024;
489 				break;
490 
491 			    case T_6250BPI:
492 			    case T_BADBPI:
493 				s = 60 * 1024;
494 				break;
495 			}
496 		}
497 		if (bp->b_bcount > s) {
498 			tprintf(sc->sc_ttyp,
499 			    "%s: write record (%d) too big: limit (%d)\n",
500 			    device_xname(sc->sc_dev), bp->b_bcount, s);
501 #if 0 /* XXX see above */
502 	    error:
503 #endif
504 			bp->b_error = EIO;
505 			biodone(bp);
506 			return;
507 		}
508 	}
509 	s = splbio();
510 	bufq_put(sc->sc_tab, bp);
511 	if (sc->sc_active == 0) {
512 		sc->sc_active = 1;
513 		mtustart(sc);
514 	}
515 	splx(s);
516 }
517 
518 static void
519 mtustart(struct mt_softc *sc)
520 {
521 
522 	dlog(LOG_DEBUG, "%s ustart", device_xname(sc->sc_dev));
523 	if (hpibreq(device_parent(sc->sc_dev), &sc->sc_hq))
524 		mtstart(sc);
525 }
526 
527 static void
528 spl_mtintr(void *arg)
529 {
530 	struct mt_softc *sc = arg;
531 	int s = splbio();
532 
533 	hpibppclear(sc->sc_hpibno);
534 	mtintr(sc);
535 	splx(s);
536 }
537 
538 static void
539 spl_mtstart(void *arg)
540 {
541 	int s = splbio();
542 
543 	mtstart(arg);
544 	splx(s);
545 }
546 
547 static void
548 mtstart(void *arg)
549 {
550 	struct mt_softc *sc = arg;
551 	struct buf *bp;
552 	short	cmdcount = 1;
553 	u_char	cmdbuf[2];
554 
555 	dlog(LOG_DEBUG, "%s start", device_xname(sc->sc_dev));
556 	sc->sc_flags &= ~MTF_WRT;
557 	bp = bufq_peek(sc->sc_tab);
558 	if ((sc->sc_flags & MTF_ALIVE) == 0 &&
559 	    ((bp->b_flags & B_CMD) == 0 || bp->b_cmd != MTRESET))
560 		goto fatalerror;
561 
562 	if (sc->sc_flags & MTF_REW) {
563 		if (!hpibpptest(sc->sc_hpibno, sc->sc_slave))
564 			goto stillrew;
565 		switch (mtreaddsj(sc, MTE_DSJ_FORCE|MTE_COMPLETE|MTE_IDLE)) {
566 		    case 0:
567 		    case 1:
568 		stillrew:
569 			if ((sc->sc_stat1 & SR1_BOT) ||
570 			    !(sc->sc_stat1 & SR1_ONLINE)) {
571 				sc->sc_flags &= ~MTF_REW;
572 				break;
573 			}
574 		    case -2:
575 			/*
576 			 * -2 means "timeout" reading DSJ, which is probably
577 			 * temporary.  This is considered OK when doing a NOP,
578 			 * but not otherwise.
579 			 */
580 			if (sc->sc_flags & (MTF_DSJTIMEO | MTF_STATTIMEO)) {
581 				callout_reset(&sc->sc_start_ch, hz >> 5,
582 				    spl_mtstart, sc);
583 				return;
584 			}
585 		    case 2:
586 			if (bp->b_cmd != MTNOP || !(bp->b_flags & B_CMD)) {
587 				bp->b_error = EBUSY;
588 				goto done;
589 			}
590 			goto done;
591 
592 		    default:
593 			goto fatalerror;
594 		}
595 	}
596 	if (bp->b_flags & B_CMD) {
597 		if (sc->sc_flags & MTF_PASTEOT) {
598 			switch(bp->b_cmd) {
599 			    case MTFSF:
600 			    case MTWEOF:
601 			    case MTFSR:
602 				bp->b_error = ENOSPC;
603 				goto done;
604 
605 			    case MTBSF:
606 			    case MTOFFL:
607 			    case MTBSR:
608 			    case MTREW:
609 				sc->sc_flags &= ~(MTF_PASTEOT | MTF_ATEOT);
610 				break;
611 			}
612 		}
613 		switch(bp->b_cmd) {
614 		    case MTFSF:
615 			if (sc->sc_flags & MTF_HITEOF)
616 				goto done;
617 			cmdbuf[0] = MTTC_FSF;
618 			break;
619 
620 		    case MTBSF:
621 			if (sc->sc_flags & MTF_HITBOF)
622 				goto done;
623 			cmdbuf[0] = MTTC_BSF;
624 			break;
625 
626 		    case MTOFFL:
627 			sc->sc_flags |= MTF_REW;
628 			cmdbuf[0] = MTTC_REWOFF;
629 			break;
630 
631 		    case MTWEOF:
632 			cmdbuf[0] = MTTC_WFM;
633 			break;
634 
635 		    case MTBSR:
636 			cmdbuf[0] = MTTC_BSR;
637 			break;
638 
639 		    case MTFSR:
640 			cmdbuf[0] = MTTC_FSR;
641 			break;
642 
643 		    case MTREW:
644 			sc->sc_flags |= MTF_REW;
645 			cmdbuf[0] = MTTC_REW;
646 			break;
647 
648 		    case MTNOP:
649 			/*
650 			 * NOP is supposed to set status bits.
651 			 * Force readdsj to do it.
652 			 */
653 			switch (mtreaddsj(sc,
654 			  MTE_DSJ_FORCE | MTE_COMPLETE | MTE_IDLE)) {
655 			    default:
656 				goto done;
657 
658 			    case -1:
659 				/*
660 				 * If this fails, perform a device clear
661 				 * to fix any protocol problems and (most
662 				 * likely) get the status.
663 				 */
664 				bp->b_cmd = MTRESET;
665 				break;
666 
667 			    case -2:
668 				callout_reset(&sc->sc_start_ch, hz >> 5,
669 				    spl_mtstart, sc);
670 				return;
671 			}
672 
673 		    case MTRESET:
674 			/*
675 			 * 1) selected device clear (send with "-2" secondary)
676 			 * 2) set timeout, then wait for "service request"
677 			 * 3) interrupt will read DSJ (and END COMPLETE-IDLE)
678 			 */
679 			if (hpibsend(sc->sc_hpibno, sc->sc_slave, -2, NULL, 0)){
680 				log(LOG_ERR, "%s can't reset",
681 				    device_xname(sc->sc_dev));
682 				goto fatalerror;
683 			}
684 			callout_reset(&sc->sc_intr_ch, 4 * hz, spl_mtintr, sc);
685 			hpibawait(sc->sc_hpibno);
686 			return;
687 
688 		    case MTSET800BPI:
689 			cmdbuf[0] = MTTC_800;
690 			break;
691 
692 		    case MTSET1600BPI:
693 			cmdbuf[0] = MTTC_1600;
694 			break;
695 
696 		    case MTSET6250BPI:
697 			cmdbuf[0] = MTTC_6250;
698 			break;
699 
700 		    case MTSET6250DC:
701 			cmdbuf[0] = MTTC_DC6250;
702 			break;
703 		}
704 	} else {
705 		if (sc->sc_flags & MTF_PASTEOT) {
706 			bp->b_error = ENOSPC;
707 			goto done;
708 		}
709 		if (bp->b_flags & B_READ) {
710 			sc->sc_flags |= MTF_IO;
711 			cmdbuf[0] = MTTC_READ;
712 		} else {
713 			sc->sc_flags |= MTF_WRT | MTF_IO;
714 			cmdbuf[0] = MTTC_WRITE;
715 			cmdbuf[1] = (bp->b_bcount + ((1 << WRITE_BITS_IGNORED) - 1)) >> WRITE_BITS_IGNORED;
716 			cmdcount = 2;
717 		}
718 	}
719 	if (hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_TCMD, cmdbuf, cmdcount)
720 	    == cmdcount) {
721 		if (sc->sc_flags & MTF_REW)
722 			goto done;
723 		hpibawait(sc->sc_hpibno);
724 		return;
725 	}
726 fatalerror:
727 	/*
728 	 * If anything fails, the drive is probably hosed, so mark it not
729 	 * "ALIVE" (but it EXISTS and is OPEN or we wouldn't be here, and
730 	 * if, last we heard, it was REWinding, remember that).
731 	 */
732 	sc->sc_flags &= MTF_EXISTS | MTF_OPEN | MTF_REW;
733 	bp->b_error = EIO;
734 done:
735 	sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF);
736 	(void)bufq_get(sc->sc_tab);
737 	biodone(bp);
738 	hpibfree(device_parent(sc->sc_dev), &sc->sc_hq);
739 	if ((bp = bufq_peek(sc->sc_tab)) == NULL)
740 		sc->sc_active = 0;
741 	else
742 		mtustart(sc);
743 }
744 
745 /*
746  * The Utah code had a bug which meant that the driver was unable to read.
747  * "rw" was initialized to bp->b_flags & B_READ before "bp" was initialized.
748  *   -- ajv@comp.vuw.ac.nz
749  */
750 static void
751 mtgo(void *arg)
752 {
753 	struct mt_softc *sc = arg;
754 	struct buf *bp;
755 	int rw;
756 
757 	dlog(LOG_DEBUG, "%s go", device_xname(sc->sc_dev));
758 	bp = bufq_peek(sc->sc_tab);
759 	rw = bp->b_flags & B_READ;
760 	hpibgo(sc->sc_hpibno, sc->sc_slave, rw ? MTT_READ : MTL_WRITE,
761 	    bp->b_data, bp->b_bcount, rw, rw != 0);
762 }
763 
764 static void
765 mtintr(void *arg)
766 {
767 	struct mt_softc *sc = arg;
768 	struct buf *bp;
769 	int i;
770 	u_char cmdbuf[4];
771 
772 	bp = bufq_peek(sc->sc_tab);
773 	if (bp == NULL) {
774 		log(LOG_ERR, "%s intr: bp == NULL", device_xname(sc->sc_dev));
775 		return;
776 	}
777 
778 	dlog(LOG_DEBUG, "%s intr", device_xname(sc->sc_dev));
779 
780 	/*
781 	 * Some operation completed.  Read status bytes and report errors.
782 	 * Clear EOF flags here `cause they're set once on specific conditions
783 	 * below when a command succeeds.
784 	 * A DSJ of 2 always means keep waiting.  If the command was READ
785 	 * (and we're in data DMA phase) stop data transfer first.
786 	 */
787 	sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF);
788 	if ((bp->b_flags & (B_CMD|B_READ)) == B_READ &&
789 	    !(sc->sc_flags & (MTF_IO | MTF_STATTIMEO | MTF_DSJTIMEO))){
790 		cmdbuf[0] = MTE_STOP;
791 		(void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD,cmdbuf,1);
792 	}
793 	switch (mtreaddsj(sc, 0)) {
794 	    case 0:
795 		break;
796 
797 	    case 1:
798 		/*
799 		 * If we're in the middle of a READ/WRITE and have yet to
800 		 * start the data transfer, a DSJ of one should terminate it.
801 		 */
802 		sc->sc_flags &= ~MTF_IO;
803 		break;
804 
805 	    case 2:
806 		(void) hpibawait(sc->sc_hpibno);
807 		return;
808 
809 	    case -2:
810 		/*
811 		 * -2 means that the drive failed to respond quickly enough
812 		 * to the request for DSJ.  It's probably just "busy" figuring
813 		 * it out and will know in a little bit...
814 		 */
815 		callout_reset(&sc->sc_intr_ch, hz >> 5, spl_mtintr, sc);
816 		return;
817 
818 	    default:
819 		log(LOG_ERR, "%s intr: can't get drive stat",
820 		    device_xname(sc->sc_dev));
821 		goto error;
822 	}
823 	if (sc->sc_stat1 & (SR1_ERR | SR1_REJECT)) {
824 		i = sc->sc_stat4 & SR4_ERCLMASK;
825 		log(LOG_ERR, "%s: %s error, retry %d, SR2/3 %x/%x, code %d",
826 			device_xname(sc->sc_dev), i == SR4_DEVICE ? "device" :
827 			(i == SR4_PROTOCOL ? "protocol" :
828 			(i == SR4_SELFTEST ? "selftest" : "unknown")),
829 			sc->sc_stat4 & SR4_RETRYMASK, sc->sc_stat2,
830 			sc->sc_stat3, sc->sc_stat5);
831 
832 		if ((bp->b_flags & B_CMD) && bp->b_cmd == MTRESET)
833 			callout_stop(&sc->sc_intr_ch);
834 		if (sc->sc_stat3 & SR3_POWERUP)
835 			sc->sc_flags &= MTF_OPEN | MTF_EXISTS;
836 		goto error;
837 	}
838 	/*
839 	 * Report and clear any soft errors.
840 	 */
841 	if (sc->sc_stat1 & SR1_SOFTERR) {
842 		log(LOG_WARNING, "%s: soft error, retry %d\n",
843 		    device_xname(sc->sc_dev), sc->sc_stat4 & SR4_RETRYMASK);
844 		sc->sc_stat1 &= ~SR1_SOFTERR;
845 	}
846 	/*
847 	 * We've initiated a read or write, but haven't actually started to
848 	 * DMA the data yet.  At this point, the drive's ready.
849 	 */
850 	if (sc->sc_flags & MTF_IO) {
851 		sc->sc_flags &= ~MTF_IO;
852 		if (hpibustart(sc->sc_hpibno))
853 			mtgo(sc);
854 		return;
855 	}
856 	/*
857 	 * Check for End Of Tape - we're allowed to hit EOT and then write (or
858 	 * read) one more record.  If we get here and have not already hit EOT,
859 	 * return ENOSPC to inform the process that it's hit it.  If we get
860 	 * here and HAVE already hit EOT, don't allow any more operations that
861 	 * move the tape forward.
862 	 */
863 	if (sc->sc_stat1 & SR1_EOT) {
864 		if (sc->sc_flags & MTF_ATEOT)
865 			sc->sc_flags |= MTF_PASTEOT;
866 		else {
867 			bp->b_error = ENOSPC;
868 			sc->sc_flags |= MTF_ATEOT;
869 		}
870 	}
871 	/*
872 	 * If a motion command was being executed, check for Tape Marks.
873 	 * If we were doing data, make sure we got the right amount, and
874 	 * check for hitting tape marks on reads.
875 	 */
876 	if (bp->b_flags & B_CMD) {
877 		if (sc->sc_stat1 & SR1_EOF) {
878 			if (bp->b_cmd == MTFSR)
879 				sc->sc_flags |= MTF_HITEOF;
880 			if (bp->b_cmd == MTBSR)
881 				sc->sc_flags |= MTF_HITBOF;
882 		}
883 		if (bp->b_cmd == MTRESET) {
884 			callout_stop(&sc->sc_intr_ch);
885 			sc->sc_flags |= MTF_ALIVE;
886 		}
887 	} else {
888 		i = hpibrecv(sc->sc_hpibno, sc->sc_slave, MTT_BCNT, cmdbuf, 2);
889 		if (i != 2) {
890 			log(LOG_ERR, "%s intr: can't get xfer length\n",
891 			    device_xname(sc->sc_dev));
892 			goto error;
893 		}
894 		i = (int) *((u_short *) cmdbuf);
895 		if (i <= bp->b_bcount) {
896 			if (i == 0)
897 				sc->sc_flags |= MTF_HITEOF;
898 			bp->b_resid = bp->b_bcount - i;
899 			dlog(LOG_DEBUG, "%s intr: bcount %d, resid %d",
900 			    device_xname(sc->sc_dev), bp->b_bcount,
901 			    bp->b_resid);
902 		} else {
903 			tprintf(sc->sc_ttyp,
904 				"%s: record (%d) larger than wanted (%d)\n",
905 				device_xname(sc->sc_dev), i, bp->b_bcount);
906  error:
907 			sc->sc_flags &= ~MTF_IO;
908 			bp->b_error = EIO;
909 		}
910 	}
911 	/*
912 	 * The operation is completely done.
913 	 * Let the drive know with an END command.
914 	 */
915 	cmdbuf[0] = MTE_COMPLETE | MTE_IDLE;
916 	(void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD, cmdbuf, 1);
917 	bp->b_flags &= ~B_CMD;
918 	(void)bufq_get(sc->sc_tab);
919 	biodone(bp);
920 	hpibfree(device_parent(sc->sc_dev), &sc->sc_hq);
921 	if (bufq_peek(sc->sc_tab) == NULL)
922 		sc->sc_active = 0;
923 	else
924 		mtustart(sc);
925 }
926 
927 static int
928 mtread(dev_t dev, struct uio *uio, int flags)
929 {
930 
931 	return physio(mtstrategy, NULL, dev, B_READ, minphys, uio);
932 }
933 
934 static int
935 mtwrite(dev_t dev, struct uio *uio, int flags)
936 {
937 
938 	return physio(mtstrategy, NULL, dev, B_WRITE, minphys, uio);
939 }
940 
941 static int
942 mtioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
943 {
944 	struct mtop *op;
945 	int cnt;
946 
947 	switch (cmd) {
948 	    case MTIOCTOP:
949 		op = (struct mtop *)data;
950 		switch(op->mt_op) {
951 		    case MTWEOF:
952 		    case MTFSF:
953 		    case MTBSR:
954 		    case MTBSF:
955 		    case MTFSR:
956 			cnt = op->mt_count;
957 			break;
958 
959 		    case MTOFFL:
960 		    case MTREW:
961 		    case MTNOP:
962 			cnt = 0;
963 			break;
964 
965 		    default:
966 			return EINVAL;
967 		}
968 		return mtcommand(dev, op->mt_op, cnt);
969 
970 	    case MTIOCGET:
971 		break;
972 
973 	    default:
974 		return EINVAL;
975 	}
976 	return 0;
977 }
978