xref: /netbsd-src/sys/arch/hp300/dev/mt.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*	$NetBSD: mt.c,v 1.45 2008/06/17 21:06:57 he 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 1.45 2008/06/17 21:06:57 he 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 	struct buf sc_bufstore;	/* XXX buffer storage */
118 };
119 
120 #ifdef DEBUG
121 int	mtdebug = 0;
122 #define	dlog	if (mtdebug) log
123 #else
124 #define	dlog	if (0) log
125 #endif
126 
127 #define	UNIT(x)		(minor(x) & 3)
128 
129 #define B_CMD		B_DEVPRIVATE	/* command buf instead of data */
130 #define	b_cmd		b_blkno		/* blkno holds cmd when B_CMD */
131 
132 static int	mtmatch(device_t, cfdata_t, void *);
133 static void	mtattach(device_t, device_t, void *);
134 
135 CFATTACH_DECL_NEW(mt, sizeof(struct mt_softc),
136     mtmatch, mtattach, NULL, NULL);
137 
138 static dev_type_open(mtopen);
139 static dev_type_close(mtclose);
140 static dev_type_read(mtread);
141 static dev_type_write(mtwrite);
142 static dev_type_ioctl(mtioctl);
143 static dev_type_strategy(mtstrategy);
144 
145 const struct bdevsw mt_bdevsw = {
146 	mtopen, mtclose, mtstrategy, mtioctl, nodump, nosize, D_TAPE
147 };
148 
149 const struct cdevsw mt_cdevsw = {
150 	mtopen, mtclose, mtread, mtwrite, mtioctl,
151 	nostop, notty, nopoll, nommap, nokqfilter, D_TAPE
152 };
153 
154 static int	mtident(struct mt_softc *, struct hpibbus_attach_args *);
155 static void	mtustart(struct mt_softc *);
156 static int	mtreaddsj(struct mt_softc *, int);
157 static int	mtcommand(dev_t, int, int);
158 static void	spl_mtintr(void *);
159 static void	spl_mtstart(void *);
160 
161 static void	mtstart(void *);
162 static void	mtgo(void *);
163 static void	mtintr(void *);
164 
165 static int
166 mtmatch(device_t parent, cfdata_t cf, void *aux)
167 {
168 	struct hpibbus_attach_args *ha = aux;
169 
170 	return mtident(NULL, ha);
171 }
172 
173 static void
174 mtattach(device_t parent, device_t self, void *aux)
175 {
176 	struct mt_softc *sc = device_private(self);
177 	struct hpibbus_attach_args *ha = aux;
178 	int unit, hpibno, slave;
179 
180 	sc->sc_dev = self;
181 	if (mtident(sc, ha) == 0) {
182 		aprint_error(": impossible!\n");
183 		return;
184 	}
185 
186 	unit = device_unit(self);
187 	hpibno = device_unit(parent);
188 	slave = ha->ha_slave;
189 
190 	bufq_alloc(&sc->sc_tab, "fcfs", 0);
191 	callout_init(&sc->sc_start_ch, 0);
192 	callout_init(&sc->sc_intr_ch, 0);
193 
194 	sc->sc_hpibno = hpibno;
195 	sc->sc_slave = slave;
196 	sc->sc_flags = MTF_EXISTS;
197 
198 	/* Initialize hpib job queue entry. */
199 	sc->sc_hq.hq_softc = sc;
200 	sc->sc_hq.hq_slave = sc->sc_slave;
201 	sc->sc_hq.hq_start = mtstart;
202 	sc->sc_hq.hq_go = mtgo;
203 	sc->sc_hq.hq_intr = mtintr;
204 }
205 
206 static int
207 mtident(struct mt_softc *sc, struct hpibbus_attach_args *ha)
208 {
209 	int i;
210 
211 	for (i = 0; i < nmtinfo; i++) {
212 		if (ha->ha_id == mtinfo[i].hwid) {
213 			if (sc != NULL) {
214 				sc->sc_type = mtinfo[i].hwid;
215 				aprint_normal(": %s tape\n", mtinfo[i].desc);
216 			}
217 			return 1;
218 		}
219 	}
220 	return 0;
221 }
222 
223 /*
224  * Perform a read of "Device Status Jump" register and update the
225  * status if necessary.  If status is read, the given "ecmd" is also
226  * performed, unless "ecmd" is zero.  Returns DSJ value, -1 on failure
227  * and -2 on "temporary" failure.
228  */
229 static int
230 mtreaddsj(struct mt_softc *sc, int ecmd)
231 {
232 	int retval;
233 
234 	if (sc->sc_flags & MTF_STATTIMEO)
235 		goto getstats;
236 	retval = hpibrecv(sc->sc_hpibno,
237 	    (sc->sc_flags & MTF_DSJTIMEO) ? -1 : sc->sc_slave,
238 	    MTT_DSJ, &(sc->sc_lastdsj), 1);
239 	sc->sc_flags &= ~MTF_DSJTIMEO;
240 	if (retval != 1) {
241 		dlog(LOG_DEBUG, "%s can't hpibrecv DSJ",
242 		    device_xname(sc->sc_dev));
243 		if (sc->sc_recvtimeo == 0)
244 			sc->sc_recvtimeo = hz;
245 		if (--sc->sc_recvtimeo == 0)
246 			return -1;
247 		if (retval == 0)
248 			sc->sc_flags |= MTF_DSJTIMEO;
249 		return -2;
250 	}
251 	sc->sc_recvtimeo = 0;
252 	sc->sc_statindex = 0;
253 	dlog(LOG_DEBUG, "%s readdsj: 0x%x", device_xname(sc->sc_dev),
254 	    sc->sc_lastdsj);
255 	sc->sc_lastecmd = ecmd;
256 	switch (sc->sc_lastdsj) {
257 	    case 0:
258 		if (ecmd & MTE_DSJ_FORCE)
259 			break;
260 		return 0;
261 
262 	    case 2:
263 		sc->sc_lastecmd = MTE_COMPLETE;
264 	    case 1:
265 		break;
266 
267 	    default:
268 		log(LOG_ERR, "%s readdsj: DSJ 0x%x\n", device_xname(sc->sc_dev),
269 		    sc->sc_lastdsj);
270 		return -1;
271 	}
272  getstats:
273 	retval = hpibrecv(sc->sc_hpibno,
274 	    (sc->sc_flags & MTF_STATCONT) ? -1 : sc->sc_slave,
275 	    MTT_STAT, ((char *)&(sc->sc_stat)) + sc->sc_statindex,
276 	    sizeof(sc->sc_stat) - sc->sc_statindex);
277 	sc->sc_flags &= ~(MTF_STATTIMEO | MTF_STATCONT);
278 	if (retval != sizeof(sc->sc_stat) - sc->sc_statindex) {
279 		if (sc->sc_recvtimeo == 0)
280 			sc->sc_recvtimeo = hz;
281 		if (--sc->sc_recvtimeo != 0) {
282 			if (retval >= 0) {
283 				sc->sc_statindex += retval;
284 				sc->sc_flags |= MTF_STATCONT;
285 			}
286 			sc->sc_flags |= MTF_STATTIMEO;
287 			return -2;
288 		}
289 		log(LOG_ERR, "%s readdsj: can't read status",
290 		    device_xname(sc->sc_dev));
291 		return -1;
292 	}
293 	sc->sc_recvtimeo = 0;
294 	sc->sc_statindex = 0;
295 	dlog(LOG_DEBUG, "%s readdsj: status is %x %x %x %x %x %x",
296 	    device_xname(sc->sc_dev),
297 	    sc->sc_stat1, sc->sc_stat2, sc->sc_stat3,
298 	    sc->sc_stat4, sc->sc_stat5, sc->sc_stat6);
299 	if (sc->sc_lastecmd)
300 		(void) hpibsend(sc->sc_hpibno, sc->sc_slave,
301 		    MTL_ECMD, &(sc->sc_lastecmd), 1);
302 	return (int)sc->sc_lastdsj;
303 }
304 
305 static int
306 mtopen(dev_t dev, int flag, int mode, struct lwp *l)
307 {
308 	struct mt_softc *sc;
309 	int req_den;
310 	int error;
311 
312 	sc = device_lookup_private(&mt_cd, UNIT(dev));
313 	if (sc == NULL)
314 		return ENXIO;
315 
316 	if ((sc->sc_flags & MTF_EXISTS) == 0)
317 		return ENXIO;
318 
319 	dlog(LOG_DEBUG, "%s open: flags 0x%x", device_xname(sc->sc_dev),
320 	    sc->sc_flags);
321 	if (sc->sc_flags & MTF_OPEN)
322 		return EBUSY;
323 	sc->sc_flags |= MTF_OPEN;
324 	sc->sc_ttyp = tprintf_open(l->l_proc);
325 	if ((sc->sc_flags & MTF_ALIVE) == 0) {
326 		error = mtcommand(dev, MTRESET, 0);
327 		if (error != 0 || (sc->sc_flags & MTF_ALIVE) == 0)
328 			goto errout;
329 		if ((sc->sc_stat1 & (SR1_BOT | SR1_ONLINE)) == SR1_ONLINE)
330 			(void) mtcommand(dev, MTREW, 0);
331 	}
332 	for (;;) {
333 		if ((error = mtcommand(dev, MTNOP, 0)) != 0)
334 			goto errout;
335 		if (!(sc->sc_flags & MTF_REW))
336 			break;
337 		if (tsleep((void *) &lbolt, PCATCH | (PZERO + 1),
338 		    "mt", 0) != 0) {
339 			error = EINTR;
340 			goto errout;
341 		}
342 	}
343 	if ((flag & FWRITE) && (sc->sc_stat1 & SR1_RO)) {
344 		error = EROFS;
345 		goto errout;
346 	}
347 	if (!(sc->sc_stat1 & SR1_ONLINE)) {
348 		uprintf("%s: not online\n", device_xname(sc->sc_dev));
349 		error = EIO;
350 		goto errout;
351 	}
352 	/*
353 	 * Select density:
354 	 *  - find out what density the drive is set to
355 	 *	(i.e. the density of the current tape)
356 	 *  - if we are going to write
357 	 *    - if we're not at the beginning of the tape
358 	 *      - complain if we want to change densities
359 	 *    - otherwise, select the mtcommand to set the density
360 	 *
361 	 * If the drive doesn't support it then don't change the recorded
362 	 * density.
363 	 *
364 	 * The original MOREbsd code had these additional conditions
365 	 * for the mid-tape change
366 	 *
367 	 *	req_den != T_BADBPI &&
368 	 *	sc->sc_density != T_6250BPI
369 	 *
370 	 * which suggests that it would be possible to write multiple
371 	 * densities if req_den == T_BAD_BPI or the current tape
372 	 * density was 6250.  Testing of our 7980 suggests that the
373 	 * device cannot change densities mid-tape.
374 	 *
375 	 * ajv@comp.vuw.ac.nz
376 	 */
377 	sc->sc_density = (sc->sc_stat2 & SR2_6250) ? T_6250BPI : (
378 			 (sc->sc_stat3 & SR3_1600) ? T_1600BPI : (
379 			 (sc->sc_stat3 & SR3_800) ? T_800BPI : -1));
380 	req_den = (dev & T_DENSEL);
381 
382 	if (flag & FWRITE) {
383 		if (!(sc->sc_stat1 & SR1_BOT)) {
384 			if (sc->sc_density != req_den) {
385 				uprintf("%s: can't change density mid-tape\n",
386 				    device_xname(sc->sc_dev));
387 				error = EIO;
388 				goto errout;
389 			}
390 		}
391 		else {
392 			int mtset_density =
393 			    (req_den == T_800BPI  ? MTSET800BPI : (
394 			     req_den == T_1600BPI ? MTSET1600BPI : (
395 			     req_den == T_6250BPI ? MTSET6250BPI : (
396 			     sc->sc_type == MT7980ID
397 						  ? MTSET6250DC
398 						  : MTSET6250BPI))));
399 			if (mtcommand(dev, mtset_density, 0) == 0)
400 				sc->sc_density = req_den;
401 		}
402 	}
403 	return 0;
404 errout:
405 	sc->sc_flags &= ~MTF_OPEN;
406 	return error;
407 }
408 
409 static int
410 mtclose(dev_t dev, int flag, int fmt, struct lwp *l)
411 {
412 	struct mt_softc *sc = device_lookup_private(&mt_cd,UNIT(dev));
413 
414 	if (sc->sc_flags & MTF_WRT) {
415 		(void) mtcommand(dev, MTWEOF, 2);
416 		(void) mtcommand(dev, MTBSF, 0);
417 	}
418 	if ((minor(dev) & T_NOREWIND) == 0)
419 		(void) mtcommand(dev, MTREW, 0);
420 	sc->sc_flags &= ~MTF_OPEN;
421 	tprintf_close(sc->sc_ttyp);
422 	return 0;
423 }
424 
425 static int
426 mtcommand(dev_t dev, int cmd, int cnt)
427 {
428 	struct mt_softc *sc = device_lookup_private(&mt_cd,UNIT(dev));
429 	struct buf *bp = &sc->sc_bufstore;
430 	int error = 0;
431 
432 #if 1
433 	if (bp->b_cflags & BC_BUSY)
434 		return EBUSY;
435 #endif
436 	bp->b_cmd = cmd;
437 	bp->b_dev = dev;
438 	do {
439 		bp->b_cflags = BC_BUSY;
440 		bp->b_flags = B_CMD;
441 		mtstrategy(bp);
442 		biowait(bp);
443 		if (bp->b_error != 0) {
444 			error = bp->b_error;
445 			break;
446 		}
447 	} while (--cnt > 0);
448 #if 0
449 	bp->b_flags = 0 /*&= ~BC_BUSY*/;
450 #else
451 	bp->b_flags &= ~BC_BUSY;
452 #endif
453 	return error;
454 }
455 
456 /*
457  * Only thing to check here is for legal record lengths (writes only).
458  */
459 static void
460 mtstrategy(struct buf *bp)
461 {
462 	struct mt_softc *sc;
463 	int s;
464 
465 	sc = device_lookup_private(&mt_cd,UNIT(bp->b_dev));
466 	dlog(LOG_DEBUG, "%s strategy", device_xname(sc->sc_dev));
467 	if ((bp->b_flags & (B_CMD | B_READ)) == 0) {
468 #define WRITE_BITS_IGNORED	8
469 #if 0
470 		if (bp->b_bcount & ((1 << WRITE_BITS_IGNORED) - 1)) {
471 			tprintf(sc->sc_ttyp,
472 			    "%s: write record must be multiple of %d\n",
473 			    device_xname(sc->sc_dev), 1 << WRITE_BITS_IGNORED);
474 			goto error;
475 		}
476 #endif
477 		s = 16 * 1024;
478 		if (sc->sc_stat2 & SR2_LONGREC) {
479 			switch (sc->sc_density) {
480 			    case T_1600BPI:
481 				s = 32 * 1024;
482 				break;
483 
484 			    case T_6250BPI:
485 			    case T_BADBPI:
486 				s = 60 * 1024;
487 				break;
488 			}
489 		}
490 		if (bp->b_bcount > s) {
491 			tprintf(sc->sc_ttyp,
492 			    "%s: write record (%d) too big: limit (%d)\n",
493 			    device_xname(sc->sc_dev), bp->b_bcount, s);
494 #if 0 /* XXX see above */
495 	    error:
496 #endif
497 			bp->b_error = EIO;
498 			biodone(bp);
499 			return;
500 		}
501 	}
502 	s = splbio();
503 	BUFQ_PUT(sc->sc_tab, bp);
504 	if (sc->sc_active == 0) {
505 		sc->sc_active = 1;
506 		mtustart(sc);
507 	}
508 	splx(s);
509 }
510 
511 static void
512 mtustart(struct mt_softc *sc)
513 {
514 
515 	dlog(LOG_DEBUG, "%s ustart", device_xname(sc->sc_dev));
516 	if (hpibreq(device_parent(sc->sc_dev), &sc->sc_hq))
517 		mtstart(sc);
518 }
519 
520 static void
521 spl_mtintr(void *arg)
522 {
523 	struct mt_softc *sc = arg;
524 	int s = splbio();
525 
526 	hpibppclear(sc->sc_hpibno);
527 	mtintr(sc);
528 	splx(s);
529 }
530 
531 static void
532 spl_mtstart(void *arg)
533 {
534 	int s = splbio();
535 
536 	mtstart(arg);
537 	splx(s);
538 }
539 
540 static void
541 mtstart(void *arg)
542 {
543 	struct mt_softc *sc = arg;
544 	struct buf *bp;
545 	short	cmdcount = 1;
546 	u_char	cmdbuf[2];
547 
548 	dlog(LOG_DEBUG, "%s start", device_xname(sc->sc_dev));
549 	sc->sc_flags &= ~MTF_WRT;
550 	bp = BUFQ_PEEK(sc->sc_tab);
551 	if ((sc->sc_flags & MTF_ALIVE) == 0 &&
552 	    ((bp->b_flags & B_CMD) == 0 || bp->b_cmd != MTRESET))
553 		goto fatalerror;
554 
555 	if (sc->sc_flags & MTF_REW) {
556 		if (!hpibpptest(sc->sc_hpibno, sc->sc_slave))
557 			goto stillrew;
558 		switch (mtreaddsj(sc, MTE_DSJ_FORCE|MTE_COMPLETE|MTE_IDLE)) {
559 		    case 0:
560 		    case 1:
561 		stillrew:
562 			if ((sc->sc_stat1 & SR1_BOT) ||
563 			    !(sc->sc_stat1 & SR1_ONLINE)) {
564 				sc->sc_flags &= ~MTF_REW;
565 				break;
566 			}
567 		    case -2:
568 			/*
569 			 * -2 means "timeout" reading DSJ, which is probably
570 			 * temporary.  This is considered OK when doing a NOP,
571 			 * but not otherwise.
572 			 */
573 			if (sc->sc_flags & (MTF_DSJTIMEO | MTF_STATTIMEO)) {
574 				callout_reset(&sc->sc_start_ch, hz >> 5,
575 				    spl_mtstart, sc);
576 				return;
577 			}
578 		    case 2:
579 			if (bp->b_cmd != MTNOP || !(bp->b_flags & B_CMD)) {
580 				bp->b_error = EBUSY;
581 				goto done;
582 			}
583 			goto done;
584 
585 		    default:
586 			goto fatalerror;
587 		}
588 	}
589 	if (bp->b_flags & B_CMD) {
590 		if (sc->sc_flags & MTF_PASTEOT) {
591 			switch(bp->b_cmd) {
592 			    case MTFSF:
593 			    case MTWEOF:
594 			    case MTFSR:
595 				bp->b_error = ENOSPC;
596 				goto done;
597 
598 			    case MTBSF:
599 			    case MTOFFL:
600 			    case MTBSR:
601 			    case MTREW:
602 				sc->sc_flags &= ~(MTF_PASTEOT | MTF_ATEOT);
603 				break;
604 			}
605 		}
606 		switch(bp->b_cmd) {
607 		    case MTFSF:
608 			if (sc->sc_flags & MTF_HITEOF)
609 				goto done;
610 			cmdbuf[0] = MTTC_FSF;
611 			break;
612 
613 		    case MTBSF:
614 			if (sc->sc_flags & MTF_HITBOF)
615 				goto done;
616 			cmdbuf[0] = MTTC_BSF;
617 			break;
618 
619 		    case MTOFFL:
620 			sc->sc_flags |= MTF_REW;
621 			cmdbuf[0] = MTTC_REWOFF;
622 			break;
623 
624 		    case MTWEOF:
625 			cmdbuf[0] = MTTC_WFM;
626 			break;
627 
628 		    case MTBSR:
629 			cmdbuf[0] = MTTC_BSR;
630 			break;
631 
632 		    case MTFSR:
633 			cmdbuf[0] = MTTC_FSR;
634 			break;
635 
636 		    case MTREW:
637 			sc->sc_flags |= MTF_REW;
638 			cmdbuf[0] = MTTC_REW;
639 			break;
640 
641 		    case MTNOP:
642 			/*
643 			 * NOP is supposed to set status bits.
644 			 * Force readdsj to do it.
645 			 */
646 			switch (mtreaddsj(sc,
647 			  MTE_DSJ_FORCE | MTE_COMPLETE | MTE_IDLE)) {
648 			    default:
649 				goto done;
650 
651 			    case -1:
652 				/*
653 				 * If this fails, perform a device clear
654 				 * to fix any protocol problems and (most
655 				 * likely) get the status.
656 				 */
657 				bp->b_cmd = MTRESET;
658 				break;
659 
660 			    case -2:
661 				callout_reset(&sc->sc_start_ch, hz >> 5,
662 				    spl_mtstart, sc);
663 				return;
664 			}
665 
666 		    case MTRESET:
667 			/*
668 			 * 1) selected device clear (send with "-2" secondary)
669 			 * 2) set timeout, then wait for "service request"
670 			 * 3) interrupt will read DSJ (and END COMPLETE-IDLE)
671 			 */
672 			if (hpibsend(sc->sc_hpibno, sc->sc_slave, -2, NULL, 0)){
673 				log(LOG_ERR, "%s can't reset",
674 				    device_xname(sc->sc_dev));
675 				goto fatalerror;
676 			}
677 			callout_reset(&sc->sc_intr_ch, 4 * hz, spl_mtintr, sc);
678 			hpibawait(sc->sc_hpibno);
679 			return;
680 
681 		    case MTSET800BPI:
682 			cmdbuf[0] = MTTC_800;
683 			break;
684 
685 		    case MTSET1600BPI:
686 			cmdbuf[0] = MTTC_1600;
687 			break;
688 
689 		    case MTSET6250BPI:
690 			cmdbuf[0] = MTTC_6250;
691 			break;
692 
693 		    case MTSET6250DC:
694 			cmdbuf[0] = MTTC_DC6250;
695 			break;
696 		}
697 	} else {
698 		if (sc->sc_flags & MTF_PASTEOT) {
699 			bp->b_error = ENOSPC;
700 			goto done;
701 		}
702 		if (bp->b_flags & B_READ) {
703 			sc->sc_flags |= MTF_IO;
704 			cmdbuf[0] = MTTC_READ;
705 		} else {
706 			sc->sc_flags |= MTF_WRT | MTF_IO;
707 			cmdbuf[0] = MTTC_WRITE;
708 			cmdbuf[1] = (bp->b_bcount + ((1 << WRITE_BITS_IGNORED) - 1)) >> WRITE_BITS_IGNORED;
709 			cmdcount = 2;
710 		}
711 	}
712 	if (hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_TCMD, cmdbuf, cmdcount)
713 	    == cmdcount) {
714 		if (sc->sc_flags & MTF_REW)
715 			goto done;
716 		hpibawait(sc->sc_hpibno);
717 		return;
718 	}
719 fatalerror:
720 	/*
721 	 * If anything fails, the drive is probably hosed, so mark it not
722 	 * "ALIVE" (but it EXISTS and is OPEN or we wouldn't be here, and
723 	 * if, last we heard, it was REWinding, remember that).
724 	 */
725 	sc->sc_flags &= MTF_EXISTS | MTF_OPEN | MTF_REW;
726 	bp->b_error = EIO;
727 done:
728 	sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF);
729 	(void)BUFQ_GET(sc->sc_tab);
730 	biodone(bp);
731 	hpibfree(device_parent(sc->sc_dev), &sc->sc_hq);
732 	if ((bp = BUFQ_PEEK(sc->sc_tab)) == NULL)
733 		sc->sc_active = 0;
734 	else
735 		mtustart(sc);
736 }
737 
738 /*
739  * The Utah code had a bug which meant that the driver was unable to read.
740  * "rw" was initialized to bp->b_flags & B_READ before "bp" was initialized.
741  *   -- ajv@comp.vuw.ac.nz
742  */
743 static void
744 mtgo(void *arg)
745 {
746 	struct mt_softc *sc = arg;
747 	struct buf *bp;
748 	int rw;
749 
750 	dlog(LOG_DEBUG, "%s go", device_xname(sc->sc_dev));
751 	bp = BUFQ_PEEK(sc->sc_tab);
752 	rw = bp->b_flags & B_READ;
753 	hpibgo(sc->sc_hpibno, sc->sc_slave, rw ? MTT_READ : MTL_WRITE,
754 	    bp->b_data, bp->b_bcount, rw, rw != 0);
755 }
756 
757 static void
758 mtintr(void *arg)
759 {
760 	struct mt_softc *sc = arg;
761 	struct buf *bp;
762 	int i;
763 	u_char cmdbuf[4];
764 
765 	bp = BUFQ_PEEK(sc->sc_tab);
766 	if (bp == NULL) {
767 		log(LOG_ERR, "%s intr: bp == NULL", device_xname(sc->sc_dev));
768 		return;
769 	}
770 
771 	dlog(LOG_DEBUG, "%s intr", device_xname(sc->sc_dev));
772 
773 	/*
774 	 * Some operation completed.  Read status bytes and report errors.
775 	 * Clear EOF flags here `cause they're set once on specific conditions
776 	 * below when a command succeeds.
777 	 * A DSJ of 2 always means keep waiting.  If the command was READ
778 	 * (and we're in data DMA phase) stop data transfer first.
779 	 */
780 	sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF);
781 	if ((bp->b_flags & (B_CMD|B_READ)) == B_READ &&
782 	    !(sc->sc_flags & (MTF_IO | MTF_STATTIMEO | MTF_DSJTIMEO))){
783 		cmdbuf[0] = MTE_STOP;
784 		(void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD,cmdbuf,1);
785 	}
786 	switch (mtreaddsj(sc, 0)) {
787 	    case 0:
788 		break;
789 
790 	    case 1:
791 		/*
792 		 * If we're in the middle of a READ/WRITE and have yet to
793 		 * start the data transfer, a DSJ of one should terminate it.
794 		 */
795 		sc->sc_flags &= ~MTF_IO;
796 		break;
797 
798 	    case 2:
799 		(void) hpibawait(sc->sc_hpibno);
800 		return;
801 
802 	    case -2:
803 		/*
804 		 * -2 means that the drive failed to respond quickly enough
805 		 * to the request for DSJ.  It's probably just "busy" figuring
806 		 * it out and will know in a little bit...
807 		 */
808 		callout_reset(&sc->sc_intr_ch, hz >> 5, spl_mtintr, sc);
809 		return;
810 
811 	    default:
812 		log(LOG_ERR, "%s intr: can't get drive stat",
813 		    device_xname(sc->sc_dev));
814 		goto error;
815 	}
816 	if (sc->sc_stat1 & (SR1_ERR | SR1_REJECT)) {
817 		i = sc->sc_stat4 & SR4_ERCLMASK;
818 		log(LOG_ERR, "%s: %s error, retry %d, SR2/3 %x/%x, code %d",
819 			device_xname(sc->sc_dev), i == SR4_DEVICE ? "device" :
820 			(i == SR4_PROTOCOL ? "protocol" :
821 			(i == SR4_SELFTEST ? "selftest" : "unknown")),
822 			sc->sc_stat4 & SR4_RETRYMASK, sc->sc_stat2,
823 			sc->sc_stat3, sc->sc_stat5);
824 
825 		if ((bp->b_flags & B_CMD) && bp->b_cmd == MTRESET)
826 			callout_stop(&sc->sc_intr_ch);
827 		if (sc->sc_stat3 & SR3_POWERUP)
828 			sc->sc_flags &= MTF_OPEN | MTF_EXISTS;
829 		goto error;
830 	}
831 	/*
832 	 * Report and clear any soft errors.
833 	 */
834 	if (sc->sc_stat1 & SR1_SOFTERR) {
835 		log(LOG_WARNING, "%s: soft error, retry %d\n",
836 		    device_xname(sc->sc_dev), sc->sc_stat4 & SR4_RETRYMASK);
837 		sc->sc_stat1 &= ~SR1_SOFTERR;
838 	}
839 	/*
840 	 * We've initiated a read or write, but haven't actually started to
841 	 * DMA the data yet.  At this point, the drive's ready.
842 	 */
843 	if (sc->sc_flags & MTF_IO) {
844 		sc->sc_flags &= ~MTF_IO;
845 		if (hpibustart(sc->sc_hpibno))
846 			mtgo(sc);
847 		return;
848 	}
849 	/*
850 	 * Check for End Of Tape - we're allowed to hit EOT and then write (or
851 	 * read) one more record.  If we get here and have not already hit EOT,
852 	 * return ENOSPC to inform the process that it's hit it.  If we get
853 	 * here and HAVE already hit EOT, don't allow any more operations that
854 	 * move the tape forward.
855 	 */
856 	if (sc->sc_stat1 & SR1_EOT) {
857 		if (sc->sc_flags & MTF_ATEOT)
858 			sc->sc_flags |= MTF_PASTEOT;
859 		else {
860 			bp->b_error = ENOSPC;
861 			sc->sc_flags |= MTF_ATEOT;
862 		}
863 	}
864 	/*
865 	 * If a motion command was being executed, check for Tape Marks.
866 	 * If we were doing data, make sure we got the right amount, and
867 	 * check for hitting tape marks on reads.
868 	 */
869 	if (bp->b_flags & B_CMD) {
870 		if (sc->sc_stat1 & SR1_EOF) {
871 			if (bp->b_cmd == MTFSR)
872 				sc->sc_flags |= MTF_HITEOF;
873 			if (bp->b_cmd == MTBSR)
874 				sc->sc_flags |= MTF_HITBOF;
875 		}
876 		if (bp->b_cmd == MTRESET) {
877 			callout_stop(&sc->sc_intr_ch);
878 			sc->sc_flags |= MTF_ALIVE;
879 		}
880 	} else {
881 		i = hpibrecv(sc->sc_hpibno, sc->sc_slave, MTT_BCNT, cmdbuf, 2);
882 		if (i != 2) {
883 			log(LOG_ERR, "%s intr: can't get xfer length\n",
884 			    device_xname(sc->sc_dev));
885 			goto error;
886 		}
887 		i = (int) *((u_short *) cmdbuf);
888 		if (i <= bp->b_bcount) {
889 			if (i == 0)
890 				sc->sc_flags |= MTF_HITEOF;
891 			bp->b_resid = bp->b_bcount - i;
892 			dlog(LOG_DEBUG, "%s intr: bcount %d, resid %d",
893 			    device_xname(sc->sc_dev), bp->b_bcount,
894 			    bp->b_resid);
895 		} else {
896 			tprintf(sc->sc_ttyp,
897 				"%s: record (%d) larger than wanted (%d)\n",
898 				device_xname(sc->sc_dev), i, bp->b_bcount);
899  error:
900 			sc->sc_flags &= ~MTF_IO;
901 			bp->b_error = EIO;
902 		}
903 	}
904 	/*
905 	 * The operation is completely done.
906 	 * Let the drive know with an END command.
907 	 */
908 	cmdbuf[0] = MTE_COMPLETE | MTE_IDLE;
909 	(void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD, cmdbuf, 1);
910 	bp->b_flags &= ~B_CMD;
911 	(void)BUFQ_GET(sc->sc_tab);
912 	biodone(bp);
913 	hpibfree(device_parent(sc->sc_dev), &sc->sc_hq);
914 	if (BUFQ_PEEK(sc->sc_tab) == NULL)
915 		sc->sc_active = 0;
916 	else
917 		mtustart(sc);
918 }
919 
920 static int
921 mtread(dev_t dev, struct uio *uio, int flags)
922 {
923 	struct mt_softc *sc = device_lookup_private(&mt_cd,UNIT(dev));
924 
925 	return physio(mtstrategy, &sc->sc_bufstore,
926 	    dev, B_READ, minphys, uio);
927 }
928 
929 static int
930 mtwrite(dev_t dev, struct uio *uio, int flags)
931 {
932 	struct mt_softc *sc = device_lookup_private(&mt_cd,UNIT(dev));
933 
934 	return physio(mtstrategy, &sc->sc_bufstore,
935 	    dev, B_WRITE, minphys, uio);
936 }
937 
938 static int
939 mtioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
940 {
941 	struct mtop *op;
942 	int cnt;
943 
944 	switch (cmd) {
945 	    case MTIOCTOP:
946 		op = (struct mtop *)data;
947 		switch(op->mt_op) {
948 		    case MTWEOF:
949 		    case MTFSF:
950 		    case MTBSR:
951 		    case MTBSF:
952 		    case MTFSR:
953 			cnt = op->mt_count;
954 			break;
955 
956 		    case MTOFFL:
957 		    case MTREW:
958 		    case MTNOP:
959 			cnt = 0;
960 			break;
961 
962 		    default:
963 			return EINVAL;
964 		}
965 		return mtcommand(dev, op->mt_op, cnt);
966 
967 	    case MTIOCGET:
968 		break;
969 
970 	    default:
971 		return EINVAL;
972 	}
973 	return 0;
974 }
975