xref: /netbsd-src/sys/dev/ata/ata.c (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /*	$NetBSD: ata.c,v 1.149 2019/05/25 16:30:18 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1998, 2001 Manuel Bouyer.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __KERNEL_RCSID(0, "$NetBSD: ata.c,v 1.149 2019/05/25 16:30:18 christos Exp $");
29 
30 #include "opt_ata.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/device.h>
36 #include <sys/conf.h>
37 #include <sys/fcntl.h>
38 #include <sys/proc.h>
39 #include <sys/kthread.h>
40 #include <sys/errno.h>
41 #include <sys/ataio.h>
42 #include <sys/kmem.h>
43 #include <sys/intr.h>
44 #include <sys/bus.h>
45 #include <sys/once.h>
46 #include <sys/bitops.h>
47 
48 #define ATABUS_PRIVATE
49 
50 #include <dev/ata/ataconf.h>
51 #include <dev/ata/atareg.h>
52 #include <dev/ata/atavar.h>
53 #include <dev/ic/wdcvar.h>	/* for PIOBM */
54 
55 #include "ioconf.h"
56 #include "locators.h"
57 
58 #include "atapibus.h"
59 #include "ataraid.h"
60 #include "sata_pmp.h"
61 
62 #if NATARAID > 0
63 #include <dev/ata/ata_raidvar.h>
64 #endif
65 #if NSATA_PMP > 0
66 #include <dev/ata/satapmpvar.h>
67 #endif
68 #include <dev/ata/satapmpreg.h>
69 
70 #define DEBUG_FUNCS  0x08
71 #define DEBUG_PROBE  0x10
72 #define DEBUG_DETACH 0x20
73 #define	DEBUG_XFERS  0x40
74 #ifdef ATADEBUG
75 #ifndef ATADEBUG_MASK
76 #define ATADEBUG_MASK 0
77 #endif
78 int atadebug_mask = ATADEBUG_MASK;
79 #define ATADEBUG_PRINT(args, level) \
80 	if (atadebug_mask & (level)) \
81 		printf args
82 #else
83 #define ATADEBUG_PRINT(args, level)
84 #endif
85 
86 static ONCE_DECL(ata_init_ctrl);
87 static struct pool ata_xfer_pool;
88 
89 /*
90  * A queue of atabus instances, used to ensure the same bus probe order
91  * for a given hardware configuration at each boot.  Kthread probing
92  * devices on a atabus.  Only one probing at once.
93  */
94 static TAILQ_HEAD(, atabus_initq)	atabus_initq_head;
95 static kmutex_t				atabus_qlock;
96 static kcondvar_t			atabus_qcv;
97 static lwp_t *				atabus_cfg_lwp;
98 
99 /*****************************************************************************
100  * ATA bus layer.
101  *
102  * ATA controllers attach an atabus instance, which handles probing the bus
103  * for drives, etc.
104  *****************************************************************************/
105 
106 dev_type_open(atabusopen);
107 dev_type_close(atabusclose);
108 dev_type_ioctl(atabusioctl);
109 
110 const struct cdevsw atabus_cdevsw = {
111 	.d_open = atabusopen,
112 	.d_close = atabusclose,
113 	.d_read = noread,
114 	.d_write = nowrite,
115 	.d_ioctl = atabusioctl,
116 	.d_stop = nostop,
117 	.d_tty = notty,
118 	.d_poll = nopoll,
119 	.d_mmap = nommap,
120 	.d_kqfilter = nokqfilter,
121 	.d_discard = nodiscard,
122 	.d_flag = D_OTHER
123 };
124 
125 static void atabus_childdetached(device_t, device_t);
126 static int atabus_rescan(device_t, const char *, const int *);
127 static bool atabus_resume(device_t, const pmf_qual_t *);
128 static bool atabus_suspend(device_t, const pmf_qual_t *);
129 static void atabusconfig_thread(void *);
130 
131 static void ata_channel_idle(struct ata_channel *);
132 static void ata_activate_xfer_locked(struct ata_channel *, struct ata_xfer *);
133 static void ata_channel_freeze_locked(struct ata_channel *);
134 static void ata_thread_wake_locked(struct ata_channel *);
135 
136 /*
137  * atabus_init:
138  *
139  *	Initialize ATA subsystem structures.
140  */
141 static int
142 atabus_init(void)
143 {
144 
145 	pool_init(&ata_xfer_pool, sizeof(struct ata_xfer), 0, 0, 0,
146 	    "ataspl", NULL, IPL_BIO);
147 	TAILQ_INIT(&atabus_initq_head);
148 	mutex_init(&atabus_qlock, MUTEX_DEFAULT, IPL_NONE);
149 	cv_init(&atabus_qcv, "atainitq");
150 	return 0;
151 }
152 
153 /*
154  * atabusprint:
155  *
156  *	Autoconfiguration print routine used by ATA controllers when
157  *	attaching an atabus instance.
158  */
159 int
160 atabusprint(void *aux, const char *pnp)
161 {
162 	struct ata_channel *chan = aux;
163 
164 	if (pnp)
165 		aprint_normal("atabus at %s", pnp);
166 	aprint_normal(" channel %d", chan->ch_channel);
167 
168 	return (UNCONF);
169 }
170 
171 /*
172  * ataprint:
173  *
174  *	Autoconfiguration print routine.
175  */
176 int
177 ataprint(void *aux, const char *pnp)
178 {
179 	struct ata_device *adev = aux;
180 
181 	if (pnp)
182 		aprint_normal("wd at %s", pnp);
183 	aprint_normal(" drive %d", adev->adev_drv_data->drive);
184 
185 	return (UNCONF);
186 }
187 
188 /*
189  * ata_channel_attach:
190  *
191  *	Common parts of attaching an atabus to an ATA controller channel.
192  */
193 void
194 ata_channel_attach(struct ata_channel *chp)
195 {
196 	if (chp->ch_flags & ATACH_DISABLED)
197 		return;
198 
199 	ata_channel_init(chp);
200 
201 	KASSERT(chp->ch_queue != NULL);
202 
203 	chp->atabus = config_found_ia(chp->ch_atac->atac_dev, "ata", chp,
204 		atabusprint);
205 }
206 
207 /*
208  * ata_channel_detach:
209  *
210  *	Common parts of detaching an atabus to an ATA controller channel.
211  */
212 void
213 ata_channel_detach(struct ata_channel *chp)
214 {
215 	if (chp->ch_flags & ATACH_DISABLED)
216 		return;
217 
218 	ata_channel_destroy(chp);
219 
220 	chp->ch_flags |= ATACH_DETACHED;
221 }
222 
223 static void
224 atabusconfig(struct atabus_softc *atabus_sc)
225 {
226 	struct ata_channel *chp = atabus_sc->sc_chan;
227 	struct atac_softc *atac = chp->ch_atac;
228 	struct atabus_initq *atabus_initq = NULL;
229 	int i, error;
230 
231 	/* we are in the atabus's thread context */
232 	ata_channel_lock(chp);
233 	chp->ch_flags |= ATACH_TH_RUN;
234 	ata_channel_unlock(chp);
235 
236 	/*
237 	 * Probe for the drives attached to controller, unless a PMP
238 	 * is already known
239 	 */
240 	/* XXX for SATA devices we will power up all drives at once */
241 	if (chp->ch_satapmp_nports == 0)
242 		(*atac->atac_probe)(chp);
243 
244 	if (chp->ch_ndrives >= 2) {
245 		ATADEBUG_PRINT(("atabusattach: ch_drive_type 0x%x 0x%x\n",
246 		    chp->ch_drive[0].drive_type, chp->ch_drive[1].drive_type),
247 		    DEBUG_PROBE);
248 	}
249 
250 	/* next operations will occurs in a separate thread */
251 	ata_channel_lock(chp);
252 	chp->ch_flags &= ~ATACH_TH_RUN;
253 	ata_channel_unlock(chp);
254 
255 	/* Make sure the devices probe in atabus order to avoid jitter. */
256 	mutex_enter(&atabus_qlock);
257 	for (;;) {
258 		atabus_initq = TAILQ_FIRST(&atabus_initq_head);
259 		if (atabus_initq->atabus_sc == atabus_sc)
260 			break;
261 		cv_wait(&atabus_qcv, &atabus_qlock);
262 	}
263 	mutex_exit(&atabus_qlock);
264 
265 	ata_channel_lock(chp);
266 
267 	/* If no drives, abort here */
268 	if (chp->ch_drive == NULL)
269 		goto out;
270 	KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
271 	for (i = 0; i < chp->ch_ndrives; i++)
272 		if (chp->ch_drive[i].drive_type != ATA_DRIVET_NONE)
273 			break;
274 	if (i == chp->ch_ndrives)
275 		goto out;
276 
277 	/* Shortcut in case we've been shutdown */
278 	if (chp->ch_flags & ATACH_SHUTDOWN)
279 		goto out;
280 
281 	ata_channel_unlock(chp);
282 
283 	if ((error = kthread_create(PRI_NONE, 0, NULL, atabusconfig_thread,
284 	    atabus_sc, &atabus_cfg_lwp,
285 	    "%scnf", device_xname(atac->atac_dev))) != 0)
286 		aprint_error_dev(atac->atac_dev,
287 		    "unable to create config thread: error %d\n", error);
288 	return;
289 
290  out:
291 	ata_channel_unlock(chp);
292 
293 	mutex_enter(&atabus_qlock);
294 	TAILQ_REMOVE(&atabus_initq_head, atabus_initq, atabus_initq);
295 	cv_broadcast(&atabus_qcv);
296 	mutex_exit(&atabus_qlock);
297 
298 	kmem_free(atabus_initq, sizeof(*atabus_initq));
299 
300 	ata_delref(chp);
301 
302 	config_pending_decr(atac->atac_dev);
303 }
304 
305 /*
306  * atabus_configthread: finish attach of atabus's childrens, in a separate
307  * kernel thread.
308  */
309 static void
310 atabusconfig_thread(void *arg)
311 {
312 	struct atabus_softc *atabus_sc = arg;
313 	struct ata_channel *chp = atabus_sc->sc_chan;
314 	struct atac_softc *atac = chp->ch_atac;
315 	struct atabus_initq *atabus_initq = NULL;
316 	int i, s;
317 
318 	/* XXX seems wrong */
319 	mutex_enter(&atabus_qlock);
320 	atabus_initq = TAILQ_FIRST(&atabus_initq_head);
321 	KASSERT(atabus_initq->atabus_sc == atabus_sc);
322 	mutex_exit(&atabus_qlock);
323 
324 	/*
325 	 * First look for a port multiplier
326 	 */
327 	if (chp->ch_ndrives == PMP_MAX_DRIVES &&
328 	    chp->ch_drive[PMP_PORT_CTL].drive_type == ATA_DRIVET_PM) {
329 #if NSATA_PMP > 0
330 		satapmp_attach(chp);
331 #else
332 		aprint_error_dev(atabus_sc->sc_dev,
333 		    "SATA port multiplier not supported\n");
334 		/* no problems going on, all drives are ATA_DRIVET_NONE */
335 #endif
336 	}
337 
338 	/*
339 	 * Attach an ATAPI bus, if needed.
340 	 */
341 	KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
342 	for (i = 0; i < chp->ch_ndrives && chp->atapibus == NULL; i++) {
343 		if (chp->ch_drive[i].drive_type == ATA_DRIVET_ATAPI) {
344 #if NATAPIBUS > 0
345 			(*atac->atac_atapibus_attach)(atabus_sc);
346 #else
347 			/*
348 			 * Fake the autoconfig "not configured" message
349 			 */
350 			aprint_normal("atapibus at %s not configured\n",
351 			    device_xname(atac->atac_dev));
352 			chp->atapibus = NULL;
353 			s = splbio();
354 			for (i = 0; i < chp->ch_ndrives; i++) {
355 				if (chp->ch_drive[i].drive_type == ATA_DRIVET_ATAPI)
356 					chp->ch_drive[i].drive_type = ATA_DRIVET_NONE;
357 			}
358 			splx(s);
359 #endif
360 			break;
361 		}
362 	}
363 
364 	for (i = 0; i < chp->ch_ndrives; i++) {
365 		struct ata_device adev;
366 		if (chp->ch_drive[i].drive_type != ATA_DRIVET_ATA &&
367 		    chp->ch_drive[i].drive_type != ATA_DRIVET_OLD) {
368 			continue;
369 		}
370 		if (chp->ch_drive[i].drv_softc != NULL)
371 			continue;
372 		memset(&adev, 0, sizeof(struct ata_device));
373 		adev.adev_bustype = atac->atac_bustype_ata;
374 		adev.adev_channel = chp->ch_channel;
375 		adev.adev_drv_data = &chp->ch_drive[i];
376 		chp->ch_drive[i].drv_softc = config_found_ia(atabus_sc->sc_dev,
377 		    "ata_hl", &adev, ataprint);
378 		if (chp->ch_drive[i].drv_softc != NULL) {
379 			ata_probe_caps(&chp->ch_drive[i]);
380 		} else {
381 			s = splbio();
382 			chp->ch_drive[i].drive_type = ATA_DRIVET_NONE;
383 			splx(s);
384 		}
385 	}
386 
387 	/* now that we know the drives, the controller can set its modes */
388 	if (atac->atac_set_modes) {
389 		(*atac->atac_set_modes)(chp);
390 		ata_print_modes(chp);
391 	}
392 #if NATARAID > 0
393 	if (atac->atac_cap & ATAC_CAP_RAID) {
394 		for (i = 0; i < chp->ch_ndrives; i++) {
395 			if (chp->ch_drive[i].drive_type == ATA_DRIVET_ATA) {
396 				ata_raid_check_component(
397 				    chp->ch_drive[i].drv_softc);
398 			}
399 		}
400 	}
401 #endif /* NATARAID > 0 */
402 
403 	/*
404 	 * reset drive_flags for unattached devices, reset state for attached
405 	 * ones
406 	 */
407 	s = splbio();
408 	for (i = 0; i < chp->ch_ndrives; i++) {
409 		if (chp->ch_drive[i].drive_type == ATA_DRIVET_PM)
410 			continue;
411 		if (chp->ch_drive[i].drv_softc == NULL) {
412 			chp->ch_drive[i].drive_flags = 0;
413 			chp->ch_drive[i].drive_type = ATA_DRIVET_NONE;
414 		} else
415 			chp->ch_drive[i].state = 0;
416 	}
417 	splx(s);
418 
419 	mutex_enter(&atabus_qlock);
420 	TAILQ_REMOVE(&atabus_initq_head, atabus_initq, atabus_initq);
421 	cv_broadcast(&atabus_qcv);
422 	mutex_exit(&atabus_qlock);
423 
424 	kmem_free(atabus_initq, sizeof(*atabus_initq));
425 
426 	ata_delref(chp);
427 
428 	config_pending_decr(atac->atac_dev);
429 	kthread_exit(0);
430 }
431 
432 /*
433  * atabus_thread:
434  *
435  *	Worker thread for the ATA bus.
436  */
437 static void
438 atabus_thread(void *arg)
439 {
440 	struct atabus_softc *sc = arg;
441 	struct ata_channel *chp = sc->sc_chan;
442 	struct ata_queue *chq = chp->ch_queue;
443 	struct ata_xfer *xfer;
444 	int i, rv;
445 
446 	ata_channel_lock(chp);
447 	chp->ch_flags |= ATACH_TH_RUN;
448 
449 	/*
450 	 * Probe the drives.  Reset type to indicate to controllers
451 	 * that can re-probe that all drives must be probed..
452 	 *
453 	 * Note: ch_ndrives may be changed during the probe.
454 	 */
455 	KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
456 	for (i = 0; i < chp->ch_ndrives; i++) {
457 		chp->ch_drive[i].drive_flags = 0;
458 		chp->ch_drive[i].drive_type = ATA_DRIVET_NONE;
459 	}
460 	ata_channel_unlock(chp);
461 
462 	atabusconfig(sc);
463 
464 	ata_channel_lock(chp);
465 	for (;;) {
466 		if ((chp->ch_flags & (ATACH_TH_RESET | ATACH_TH_DRIVE_RESET
467 		    | ATACH_TH_RECOVERY | ATACH_SHUTDOWN)) == 0 &&
468 		    (chq->queue_active == 0 || chq->queue_freeze == 0)) {
469 			chp->ch_flags &= ~ATACH_TH_RUN;
470 			cv_wait(&chp->ch_thr_idle, &chp->ch_lock);
471 			chp->ch_flags |= ATACH_TH_RUN;
472 		}
473 		if (chp->ch_flags & ATACH_SHUTDOWN) {
474 			break;
475 		}
476 		if (chp->ch_flags & ATACH_TH_RESCAN) {
477 			chp->ch_flags &= ~ATACH_TH_RESCAN;
478 			ata_channel_unlock(chp);
479 			atabusconfig(sc);
480 			ata_channel_lock(chp);
481 		}
482 		if (chp->ch_flags & ATACH_TH_RESET) {
483 			/* this will unfreeze the channel */
484 			ata_thread_run(chp, AT_WAIT,
485 			    ATACH_TH_RESET, ATACH_NODRIVE);
486 		} else if (chp->ch_flags & ATACH_TH_DRIVE_RESET) {
487 			/* this will unfreeze the channel */
488 			for (i = 0; i < chp->ch_ndrives; i++) {
489 				struct ata_drive_datas *drvp;
490 
491 				drvp = &chp->ch_drive[i];
492 
493 				if (drvp->drive_flags & ATA_DRIVE_TH_RESET) {
494 					ata_thread_run(chp,
495 					    AT_WAIT, ATACH_TH_DRIVE_RESET, i);
496 				}
497 			}
498 			chp->ch_flags &= ~ATACH_TH_DRIVE_RESET;
499 		} else if (chp->ch_flags & ATACH_TH_RECOVERY) {
500 			/*
501 			 * This will unfreeze the channel; drops locks during
502 			 * run, so must wrap in splbio()/splx() to avoid
503 			 * spurious interrupts. XXX MPSAFE
504 			 */
505 			int s = splbio();
506 			ata_thread_run(chp, AT_WAIT, ATACH_TH_RECOVERY,
507 			    chp->recovery_tfd);
508 			splx(s);
509 		} else if (chq->queue_active > 0 && chq->queue_freeze == 1) {
510 			/*
511 			 * Caller has bumped queue_freeze, decrease it. This
512 			 * flow shalt never be executed for NCQ commands.
513 			 */
514 			KASSERT((chp->ch_flags & ATACH_NCQ) == 0);
515 			KASSERT(chq->queue_active == 1);
516 
517 			ata_channel_thaw_locked(chp);
518 			xfer = ata_queue_get_active_xfer_locked(chp);
519 
520 			KASSERT(xfer != NULL);
521 			KASSERT((xfer->c_flags & C_POLL) == 0);
522 
523 			switch ((rv = ata_xfer_start(xfer))) {
524 			case ATASTART_STARTED:
525 			case ATASTART_POLL:
526 			case ATASTART_ABORT:
527 				break;
528 			case ATASTART_TH:
529 			default:
530 				panic("%s: ata_xfer_start() unexpected rv %d",
531 				    __func__, rv);
532 				/* NOTREACHED */
533 			}
534 		} else if (chq->queue_freeze > 1)
535 			panic("%s: queue_freeze", __func__);
536 
537 		/* Try to run down the queue once channel is unfrozen */
538 		if (chq->queue_freeze == 0) {
539 			ata_channel_unlock(chp);
540 			atastart(chp);
541 			ata_channel_lock(chp);
542 		}
543 	}
544 	chp->ch_thread = NULL;
545 	cv_signal(&chp->ch_thr_idle);
546 	ata_channel_unlock(chp);
547 	kthread_exit(0);
548 }
549 
550 static void
551 ata_thread_wake_locked(struct ata_channel *chp)
552 {
553 	KASSERT(mutex_owned(&chp->ch_lock));
554 	ata_channel_freeze_locked(chp);
555 	cv_signal(&chp->ch_thr_idle);
556 }
557 
558 /*
559  * atabus_match:
560  *
561  *	Autoconfiguration match routine.
562  */
563 static int
564 atabus_match(device_t parent, cfdata_t cf, void *aux)
565 {
566 	struct ata_channel *chp = aux;
567 
568 	if (chp == NULL)
569 		return (0);
570 
571 	if (cf->cf_loc[ATACF_CHANNEL] != chp->ch_channel &&
572 	    cf->cf_loc[ATACF_CHANNEL] != ATACF_CHANNEL_DEFAULT)
573 		return (0);
574 
575 	return (1);
576 }
577 
578 /*
579  * atabus_attach:
580  *
581  *	Autoconfiguration attach routine.
582  */
583 static void
584 atabus_attach(device_t parent, device_t self, void *aux)
585 {
586 	struct atabus_softc *sc = device_private(self);
587 	struct ata_channel *chp = aux;
588 	struct atabus_initq *initq;
589 	int error;
590 
591 	sc->sc_chan = chp;
592 
593 	aprint_normal("\n");
594 	aprint_naive("\n");
595 
596 	sc->sc_dev = self;
597 
598 	if (ata_addref(chp))
599 		return;
600 
601 	RUN_ONCE(&ata_init_ctrl, atabus_init);
602 
603 	initq = kmem_zalloc(sizeof(*initq), KM_SLEEP);
604 	initq->atabus_sc = sc;
605 	mutex_enter(&atabus_qlock);
606 	TAILQ_INSERT_TAIL(&atabus_initq_head, initq, atabus_initq);
607 	mutex_exit(&atabus_qlock);
608 	config_pending_incr(sc->sc_dev);
609 
610 	/* XXX MPSAFE - no KTHREAD_MPSAFE, so protected by KERNEL_LOCK() */
611 	if ((error = kthread_create(PRI_NONE, 0, NULL, atabus_thread, sc,
612 	    &chp->ch_thread, "%s", device_xname(self))) != 0)
613 		aprint_error_dev(self,
614 		    "unable to create kernel thread: error %d\n", error);
615 
616 	if (!pmf_device_register(self, atabus_suspend, atabus_resume))
617 		aprint_error_dev(self, "couldn't establish power handler\n");
618 }
619 
620 /*
621  * atabus_detach:
622  *
623  *	Autoconfiguration detach routine.
624  */
625 static int
626 atabus_detach(device_t self, int flags)
627 {
628 	struct atabus_softc *sc = device_private(self);
629 	struct ata_channel *chp = sc->sc_chan;
630 	device_t dev = NULL;
631 	int i, error = 0;
632 
633 	/*
634 	 * Detach atapibus and its children.
635 	 */
636 	if ((dev = chp->atapibus) != NULL) {
637 		ATADEBUG_PRINT(("atabus_detach: %s: detaching %s\n",
638 		    device_xname(self), device_xname(dev)), DEBUG_DETACH);
639 
640 		error = config_detach(dev, flags);
641 		if (error)
642 			goto out;
643 		KASSERT(chp->atapibus == NULL);
644 	}
645 
646 	KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
647 
648 	/*
649 	 * Detach our other children.
650 	 */
651 	for (i = 0; i < chp->ch_ndrives; i++) {
652 		if (chp->ch_drive[i].drive_type == ATA_DRIVET_ATAPI)
653 			continue;
654 		if (chp->ch_drive[i].drive_type == ATA_DRIVET_PM)
655 			chp->ch_drive[i].drive_type = ATA_DRIVET_NONE;
656 		if ((dev = chp->ch_drive[i].drv_softc) != NULL) {
657 			ATADEBUG_PRINT(("%s.%d: %s: detaching %s\n", __func__,
658 			    __LINE__, device_xname(self), device_xname(dev)),
659 			    DEBUG_DETACH);
660 			error = config_detach(dev, flags);
661 			if (error)
662 				goto out;
663 			KASSERT(chp->ch_drive[i].drv_softc == NULL);
664 			KASSERT(chp->ch_drive[i].drive_type == 0);
665 		}
666 	}
667 
668 	/* Shutdown the channel. */
669 	ata_channel_lock(chp);
670 	chp->ch_flags |= ATACH_SHUTDOWN;
671 	while (chp->ch_thread != NULL) {
672 		cv_signal(&chp->ch_thr_idle);
673 		cv_wait(&chp->ch_thr_idle, &chp->ch_lock);
674 	}
675 	ata_channel_unlock(chp);
676 
677 	atabus_free_drives(chp);
678 
679  out:
680 #ifdef ATADEBUG
681 	if (dev != NULL && error != 0)
682 		ATADEBUG_PRINT(("%s: %s: error %d detaching %s\n", __func__,
683 		    device_xname(self), error, device_xname(dev)),
684 		    DEBUG_DETACH);
685 #endif /* ATADEBUG */
686 
687 	return (error);
688 }
689 
690 void
691 atabus_childdetached(device_t self, device_t child)
692 {
693 	bool found = false;
694 	struct atabus_softc *sc = device_private(self);
695 	struct ata_channel *chp = sc->sc_chan;
696 	int i;
697 
698 	KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
699 	/*
700 	 * atapibus detached.
701 	 */
702 	if (child == chp->atapibus) {
703 		chp->atapibus = NULL;
704 		found = true;
705 		for (i = 0; i < chp->ch_ndrives; i++) {
706 			if (chp->ch_drive[i].drive_type != ATA_DRIVET_ATAPI)
707 				continue;
708 			KASSERT(chp->ch_drive[i].drv_softc != NULL);
709 			chp->ch_drive[i].drv_softc = NULL;
710 			chp->ch_drive[i].drive_flags = 0;
711 			chp->ch_drive[i].drive_type = ATA_DRIVET_NONE;
712 		}
713 	}
714 
715 	/*
716 	 * Detach our other children.
717 	 */
718 	for (i = 0; i < chp->ch_ndrives; i++) {
719 		if (chp->ch_drive[i].drive_type == ATA_DRIVET_ATAPI)
720 			continue;
721 		if (child == chp->ch_drive[i].drv_softc) {
722 			chp->ch_drive[i].drv_softc = NULL;
723 			chp->ch_drive[i].drive_flags = 0;
724 			if (chp->ch_drive[i].drive_type == ATA_DRIVET_PM)
725 				chp->ch_satapmp_nports = 0;
726 			chp->ch_drive[i].drive_type = ATA_DRIVET_NONE;
727 			found = true;
728 		}
729 	}
730 
731 	if (!found)
732 		panic("%s: unknown child %p", device_xname(self),
733 		    (const void *)child);
734 }
735 
736 CFATTACH_DECL3_NEW(atabus, sizeof(struct atabus_softc),
737     atabus_match, atabus_attach, atabus_detach, NULL, atabus_rescan,
738     atabus_childdetached, DVF_DETACH_SHUTDOWN);
739 
740 /*****************************************************************************
741  * Common ATA bus operations.
742  *****************************************************************************/
743 
744 /* allocate/free the channel's ch_drive[] array */
745 int
746 atabus_alloc_drives(struct ata_channel *chp, int ndrives)
747 {
748 	int i;
749 	if (chp->ch_ndrives != ndrives)
750 		atabus_free_drives(chp);
751 	if (chp->ch_drive == NULL) {
752 		chp->ch_drive = kmem_zalloc(
753 		    sizeof(struct ata_drive_datas) * ndrives, KM_NOSLEEP);
754 	}
755 	if (chp->ch_drive == NULL) {
756 	    aprint_error_dev(chp->ch_atac->atac_dev,
757 		"can't alloc drive array\n");
758 	    chp->ch_ndrives = 0;
759 	    return ENOMEM;
760 	};
761 	for (i = 0; i < ndrives; i++) {
762 		chp->ch_drive[i].chnl_softc = chp;
763 		chp->ch_drive[i].drive = i;
764 	}
765 	chp->ch_ndrives = ndrives;
766 	return 0;
767 }
768 
769 void
770 atabus_free_drives(struct ata_channel *chp)
771 {
772 #ifdef DIAGNOSTIC
773 	int i;
774 	int dopanic = 0;
775 	KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
776 	for (i = 0; i < chp->ch_ndrives; i++) {
777 		if (chp->ch_drive[i].drive_type != ATA_DRIVET_NONE) {
778 			printf("%s: ch_drive[%d] type %d != ATA_DRIVET_NONE\n",
779 			    device_xname(chp->atabus), i,
780 			    chp->ch_drive[i].drive_type);
781 			dopanic = 1;
782 		}
783 		if (chp->ch_drive[i].drv_softc != NULL) {
784 			printf("%s: ch_drive[%d] attached to %s\n",
785 			    device_xname(chp->atabus), i,
786 			    device_xname(chp->ch_drive[i].drv_softc));
787 			dopanic = 1;
788 		}
789 	}
790 	if (dopanic)
791 		panic("atabus_free_drives");
792 #endif
793 
794 	if (chp->ch_drive == NULL)
795 		return;
796 	kmem_free(chp->ch_drive,
797 	    sizeof(struct ata_drive_datas) * chp->ch_ndrives);
798 	chp->ch_ndrives = 0;
799 	chp->ch_drive = NULL;
800 }
801 
802 /* Get the disk's parameters */
803 int
804 ata_get_params(struct ata_drive_datas *drvp, uint8_t flags,
805     struct ataparams *prms)
806 {
807 	struct ata_xfer *xfer;
808 	struct ata_channel *chp = drvp->chnl_softc;
809 	struct atac_softc *atac = chp->ch_atac;
810 	char *tb;
811 	int i, rv;
812 	uint16_t *p;
813 
814 	ATADEBUG_PRINT(("%s\n", __func__), DEBUG_FUNCS);
815 
816 	xfer = ata_get_xfer(chp, false);
817 	if (xfer == NULL) {
818 		ATADEBUG_PRINT(("%s: no xfer\n", __func__),
819 		    DEBUG_FUNCS|DEBUG_PROBE);
820 		return CMD_AGAIN;
821 	}
822 
823 	tb = kmem_zalloc(ATA_BSIZE, KM_SLEEP);
824 	memset(prms, 0, sizeof(struct ataparams));
825 
826 	if (drvp->drive_type == ATA_DRIVET_ATA) {
827 		xfer->c_ata_c.r_command = WDCC_IDENTIFY;
828 		xfer->c_ata_c.r_st_bmask = WDCS_DRDY;
829 		xfer->c_ata_c.r_st_pmask = WDCS_DRQ;
830 		xfer->c_ata_c.timeout = 3000; /* 3s */
831 	} else if (drvp->drive_type == ATA_DRIVET_ATAPI) {
832 		xfer->c_ata_c.r_command = ATAPI_IDENTIFY_DEVICE;
833 		xfer->c_ata_c.r_st_bmask = 0;
834 		xfer->c_ata_c.r_st_pmask = WDCS_DRQ;
835 		xfer->c_ata_c.timeout = 10000; /* 10s */
836 	} else {
837 		ATADEBUG_PRINT(("ata_get_parms: no disks\n"),
838 		    DEBUG_FUNCS|DEBUG_PROBE);
839 		rv = CMD_ERR;
840 		goto out;
841 	}
842 	xfer->c_ata_c.flags = AT_READ | flags;
843 	xfer->c_ata_c.data = tb;
844 	xfer->c_ata_c.bcount = ATA_BSIZE;
845 	if ((*atac->atac_bustype_ata->ata_exec_command)(drvp,
846 						xfer) != ATACMD_COMPLETE) {
847 		ATADEBUG_PRINT(("ata_get_parms: wdc_exec_command failed\n"),
848 		    DEBUG_FUNCS|DEBUG_PROBE);
849 		rv = CMD_AGAIN;
850 		goto out;
851 	}
852 	if (xfer->c_ata_c.flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
853 		ATADEBUG_PRINT(("ata_get_parms: ata_c.flags=0x%x\n",
854 		    xfer->c_ata_c.flags), DEBUG_FUNCS|DEBUG_PROBE);
855 		rv = CMD_ERR;
856 		goto out;
857 	}
858 	/* if we didn't read any data something is wrong */
859 	if ((xfer->c_ata_c.flags & AT_XFDONE) == 0) {
860 		rv = CMD_ERR;
861 		goto out;
862 	}
863 
864 	/* Read in parameter block. */
865 	memcpy(prms, tb, sizeof(struct ataparams));
866 
867 	/*
868 	 * Shuffle string byte order.
869 	 * ATAPI NEC, Mitsumi and Pioneer drives and
870 	 * old ATA TDK CompactFlash cards
871 	 * have different byte order.
872 	 */
873 #if BYTE_ORDER == BIG_ENDIAN
874 # define M(n)	prms->atap_model[(n) ^ 1]
875 #else
876 # define M(n)	prms->atap_model[n]
877 #endif
878 	if (
879 #if BYTE_ORDER == BIG_ENDIAN
880 	    !
881 #endif
882 	    ((drvp->drive_type == ATA_DRIVET_ATAPI) ?
883 	     ((M(0) == 'N' && M(1) == 'E') ||
884 	      (M(0) == 'F' && M(1) == 'X') ||
885 	      (M(0) == 'P' && M(1) == 'i')) :
886 	     ((M(0) == 'T' && M(1) == 'D' && M(2) == 'K')))) {
887 		rv = CMD_OK;
888 		goto out;
889 	     }
890 #undef M
891 	for (i = 0; i < sizeof(prms->atap_model); i += 2) {
892 		p = (uint16_t *)(prms->atap_model + i);
893 		*p = bswap16(*p);
894 	}
895 	for (i = 0; i < sizeof(prms->atap_serial); i += 2) {
896 		p = (uint16_t *)(prms->atap_serial + i);
897 		*p = bswap16(*p);
898 	}
899 	for (i = 0; i < sizeof(prms->atap_revision); i += 2) {
900 		p = (uint16_t *)(prms->atap_revision + i);
901 		*p = bswap16(*p);
902 	}
903 
904 	rv = CMD_OK;
905  out:
906 	kmem_free(tb, ATA_BSIZE);
907 	ata_free_xfer(chp, xfer);
908 	return rv;
909 }
910 
911 int
912 ata_set_mode(struct ata_drive_datas *drvp, uint8_t mode, uint8_t flags)
913 {
914 	struct ata_xfer *xfer;
915 	int rv;
916 	struct ata_channel *chp = drvp->chnl_softc;
917 	struct atac_softc *atac = chp->ch_atac;
918 
919 	ATADEBUG_PRINT(("ata_set_mode=0x%x\n", mode), DEBUG_FUNCS);
920 
921 	xfer = ata_get_xfer(chp, false);
922 	if (xfer == NULL) {
923 		ATADEBUG_PRINT(("%s: no xfer\n", __func__),
924 		    DEBUG_FUNCS|DEBUG_PROBE);
925 		return CMD_AGAIN;
926 	}
927 
928 	xfer->c_ata_c.r_command = SET_FEATURES;
929 	xfer->c_ata_c.r_st_bmask = 0;
930 	xfer->c_ata_c.r_st_pmask = 0;
931 	xfer->c_ata_c.r_features = WDSF_SET_MODE;
932 	xfer->c_ata_c.r_count = mode;
933 	xfer->c_ata_c.flags = flags;
934 	xfer->c_ata_c.timeout = 1000; /* 1s */
935 	if ((*atac->atac_bustype_ata->ata_exec_command)(drvp,
936 						xfer) != ATACMD_COMPLETE) {
937 		rv = CMD_AGAIN;
938 		goto out;
939 	}
940 	if (xfer->c_ata_c.flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
941 		rv = CMD_ERR;
942 		goto out;
943 	}
944 
945 	rv = CMD_OK;
946 
947 out:
948 	ata_free_xfer(chp, xfer);
949 	return rv;
950 }
951 
952 #if NATA_DMA
953 void
954 ata_dmaerr(struct ata_drive_datas *drvp, int flags)
955 {
956 	ata_channel_lock_owned(drvp->chnl_softc);
957 
958 	/*
959 	 * Downgrade decision: if we get NERRS_MAX in NXFER.
960 	 * We start with n_dmaerrs set to NERRS_MAX-1 so that the
961 	 * first error within the first NXFER ops will immediatly trigger
962 	 * a downgrade.
963 	 * If we got an error and n_xfers is bigger than NXFER reset counters.
964 	 */
965 	drvp->n_dmaerrs++;
966 	if (drvp->n_dmaerrs >= NERRS_MAX && drvp->n_xfers <= NXFER) {
967 		ata_downgrade_mode(drvp, flags);
968 		drvp->n_dmaerrs = NERRS_MAX-1;
969 		drvp->n_xfers = 0;
970 		return;
971 	}
972 	if (drvp->n_xfers > NXFER) {
973 		drvp->n_dmaerrs = 1; /* just got an error */
974 		drvp->n_xfers = 1; /* restart counting from this error */
975 	}
976 }
977 #endif	/* NATA_DMA */
978 
979 /*
980  * freeze the queue and wait for the controller to be idle. Caller has to
981  * unfreeze/restart the queue
982  */
983 static void
984 ata_channel_idle(struct ata_channel *chp)
985 {
986 	ata_channel_lock(chp);
987 	ata_channel_freeze_locked(chp);
988 	while (chp->ch_queue->queue_active > 0) {
989 		chp->ch_queue->queue_flags |= QF_IDLE_WAIT;
990 		cv_timedwait(&chp->ch_queue->queue_idle, &chp->ch_lock, 1);
991 	}
992 	ata_channel_unlock(chp);
993 }
994 
995 /*
996  * Add a command to the queue and start controller.
997  *
998  * MUST BE CALLED AT splbio()!
999  */
1000 void
1001 ata_exec_xfer(struct ata_channel *chp, struct ata_xfer *xfer)
1002 {
1003 
1004 	ATADEBUG_PRINT(("ata_exec_xfer %p channel %d drive %d\n", xfer,
1005 	    chp->ch_channel, xfer->c_drive), DEBUG_XFERS);
1006 
1007 	/* complete xfer setup */
1008 	xfer->c_chp = chp;
1009 
1010 	ata_channel_lock(chp);
1011 
1012 	/*
1013 	 * Standard commands are added to the end of command list, but
1014 	 * recovery commands must be run immediatelly.
1015 	 */
1016 	if ((xfer->c_flags & C_SKIP_QUEUE) == 0)
1017 		SIMPLEQ_INSERT_TAIL(&chp->ch_queue->queue_xfer, xfer,
1018 		    c_xferchain);
1019 	else
1020 		SIMPLEQ_INSERT_HEAD(&chp->ch_queue->queue_xfer, xfer,
1021 		    c_xferchain);
1022 
1023 	/*
1024 	 * if polling and can sleep, wait for the xfer to be at head of queue
1025 	 */
1026 	if ((xfer->c_flags & (C_POLL | C_WAIT)) ==  (C_POLL | C_WAIT)) {
1027 		while (chp->ch_queue->queue_active > 0 ||
1028 		    SIMPLEQ_FIRST(&chp->ch_queue->queue_xfer) != xfer) {
1029 			xfer->c_flags |= C_WAITACT;
1030 			cv_wait(&chp->ch_queue->c_active, &chp->ch_lock);
1031 			xfer->c_flags &= ~C_WAITACT;
1032 		}
1033 
1034 		/*
1035 		 * Free xfer now if it there was attempt to free it
1036 		 * while we were waiting.
1037 		 */
1038 		if ((xfer->c_flags & (C_FREE|C_WAITTIMO)) == C_FREE) {
1039 			ata_channel_unlock(chp);
1040 
1041 			ata_free_xfer(chp, xfer);
1042 			return;
1043 		}
1044 	}
1045 
1046 	ata_channel_unlock(chp);
1047 
1048 	ATADEBUG_PRINT(("atastart from ata_exec_xfer, flags 0x%x\n",
1049 	    chp->ch_flags), DEBUG_XFERS);
1050 	atastart(chp);
1051 }
1052 
1053 /*
1054  * Start I/O on a controller, for the given channel.
1055  * The first xfer may be not for our channel if the channel queues
1056  * are shared.
1057  *
1058  * MUST BE CALLED AT splbio()!
1059  *
1060  * XXX FIS-based switching with PMP
1061  * Currently atastart() never schedules concurrent NCQ transfers to more than
1062  * one drive, even when channel has several SATA drives attached via PMP.
1063  * To support concurrent transfers to different drives with PMP, it would be
1064  * necessary to implement FIS-based switching support in controller driver,
1065  * and then adjust error handling and recovery to stop assuming at most
1066  * one active drive.
1067  */
1068 void
1069 atastart(struct ata_channel *chp)
1070 {
1071 	struct atac_softc *atac = chp->ch_atac;
1072 	struct ata_queue *chq = chp->ch_queue;
1073 	struct ata_xfer *xfer, *axfer;
1074 	bool skipq;
1075 
1076 #ifdef ATA_DEBUG
1077 	int spl1, spl2;
1078 
1079 	spl1 = splbio();
1080 	spl2 = splbio();
1081 	if (spl2 != spl1) {
1082 		printf("atastart: not at splbio()\n");
1083 		panic("atastart");
1084 	}
1085 	splx(spl2);
1086 	splx(spl1);
1087 #endif /* ATA_DEBUG */
1088 
1089 	ata_channel_lock(chp);
1090 
1091 again:
1092 	/* is there a xfer ? */
1093 	if ((xfer = SIMPLEQ_FIRST(&chp->ch_queue->queue_xfer)) == NULL) {
1094 		ATADEBUG_PRINT(("%s(chp=%p): channel %d queue_xfer is empty\n",
1095 		    __func__, chp, chp->ch_channel), DEBUG_XFERS);
1096 		goto out;
1097 	}
1098 
1099 	/*
1100 	 * if someone is waiting for the command to be active, wake it up
1101 	 * and let it process the command
1102 	 */
1103 	if (__predict_false(xfer->c_flags & C_WAITACT)) {
1104 		ATADEBUG_PRINT(("atastart: xfer %p channel %d drive %d "
1105 		    "wait active\n", xfer, chp->ch_channel, xfer->c_drive),
1106 		    DEBUG_XFERS);
1107 		cv_broadcast(&chp->ch_queue->c_active);
1108 		goto out;
1109 	}
1110 
1111 	skipq = ISSET(xfer->c_flags, C_SKIP_QUEUE);
1112 
1113 	/* is the queue frozen? */
1114 	if (__predict_false(!skipq && chq->queue_freeze > 0)) {
1115 		if (chq->queue_flags & QF_IDLE_WAIT) {
1116 			chq->queue_flags &= ~QF_IDLE_WAIT;
1117 			cv_signal(&chp->ch_queue->queue_idle);
1118 		}
1119 		ATADEBUG_PRINT(("%s(chp=%p): channel %d drive %d "
1120 		    "queue frozen: %d\n",
1121 		    __func__, chp, chp->ch_channel, xfer->c_drive,
1122 		    chq->queue_freeze),
1123 		    DEBUG_XFERS);
1124 		goto out;
1125 	}
1126 
1127 	/* all xfers on same queue must belong to the same channel */
1128 	KASSERT(xfer->c_chp == chp);
1129 
1130 	/*
1131 	 * Can only take the command if there are no current active
1132 	 * commands, or if the command is NCQ and the active commands are also
1133 	 * NCQ. If PM is in use and HBA driver doesn't support/use FIS-based
1134 	 * switching, can only send commands to single drive.
1135 	 * Need only check first xfer.
1136 	 * XXX FIS-based switching - revisit
1137 	 */
1138 	if (!skipq && (axfer = TAILQ_FIRST(&chp->ch_queue->active_xfers))) {
1139 		if (!ISSET(xfer->c_flags, C_NCQ) ||
1140 		    !ISSET(axfer->c_flags, C_NCQ) ||
1141 		    xfer->c_drive != axfer->c_drive)
1142 			goto out;
1143 	}
1144 
1145 	struct ata_drive_datas * const drvp = &chp->ch_drive[xfer->c_drive];
1146 
1147 	/*
1148 	 * Are we on limit of active xfers ? If the queue has more
1149 	 * than 1 openings, we keep one slot reserved for recovery or dump.
1150 	 */
1151 	KASSERT(chq->queue_active <= chq->queue_openings);
1152 	const uint8_t chq_openings = (!skipq && chq->queue_openings > 1)
1153 	    ? (chq->queue_openings - 1) : chq->queue_openings;
1154 	const uint8_t drv_openings = ISSET(xfer->c_flags, C_NCQ)
1155 	    ? drvp->drv_openings : ATA_MAX_OPENINGS;
1156 	if (chq->queue_active >= MIN(chq_openings, drv_openings)) {
1157 		if (skipq) {
1158 			panic("%s: channel %d busy, xfer not possible",
1159 			    __func__, chp->ch_channel);
1160 		}
1161 
1162 		ATADEBUG_PRINT(("%s(chp=%p): channel %d completely busy\n",
1163 		    __func__, chp, chp->ch_channel), DEBUG_XFERS);
1164 		goto out;
1165 	}
1166 
1167 	/* Slot allocation can fail if drv_openings < ch_openings */
1168 	if (!ata_queue_alloc_slot(chp, &xfer->c_slot, drv_openings))
1169 		goto out;
1170 
1171 	if (__predict_false(atac->atac_claim_hw)) {
1172 		if (!atac->atac_claim_hw(chp, 0)) {
1173 			ata_queue_free_slot(chp, xfer->c_slot);
1174 			goto out;
1175 		}
1176 	}
1177 
1178 	/* Now committed to start the xfer */
1179 
1180 	ATADEBUG_PRINT(("%s(chp=%p): xfer %p channel %d drive %d\n",
1181 	    __func__, chp, xfer, chp->ch_channel, xfer->c_drive), DEBUG_XFERS);
1182 	if (drvp->drive_flags & ATA_DRIVE_RESET) {
1183 		drvp->drive_flags &= ~ATA_DRIVE_RESET;
1184 		drvp->state = 0;
1185 	}
1186 
1187 	if (ISSET(xfer->c_flags, C_NCQ))
1188 		SET(chp->ch_flags, ATACH_NCQ);
1189 	else
1190 		CLR(chp->ch_flags, ATACH_NCQ);
1191 
1192 	SIMPLEQ_REMOVE_HEAD(&chq->queue_xfer, c_xferchain);
1193 
1194 	ata_activate_xfer_locked(chp, xfer);
1195 
1196 	if (atac->atac_cap & ATAC_CAP_NOIRQ)
1197 		KASSERT(xfer->c_flags & C_POLL);
1198 
1199 	switch (ata_xfer_start(xfer)) {
1200 	case ATASTART_TH:
1201 	case ATASTART_ABORT:
1202 		/* don't start any further commands in this case */
1203 		goto out;
1204 	default:
1205 		/* nothing to do */
1206 		break;
1207 	}
1208 
1209 	/* Queue more commands if possible, but not during recovery or dump */
1210 	if (!skipq && chq->queue_active < chq->queue_openings)
1211 		goto again;
1212 
1213 out:
1214 	ata_channel_unlock(chp);
1215 }
1216 
1217 int
1218 ata_xfer_start(struct ata_xfer *xfer)
1219 {
1220 	struct ata_channel *chp = xfer->c_chp;
1221 	int rv;
1222 
1223 	KASSERT(mutex_owned(&chp->ch_lock));
1224 
1225 	rv = xfer->ops->c_start(chp, xfer);
1226 	switch (rv) {
1227 	case ATASTART_STARTED:
1228 		/* nothing to do */
1229 		break;
1230 	case ATASTART_TH:
1231 		/* postpone xfer to thread */
1232 		ata_thread_wake_locked(chp);
1233 		break;
1234 	case ATASTART_POLL:
1235 		/* can happen even in thread context for some ATAPI devices */
1236 		ata_channel_unlock(chp);
1237 		KASSERT(xfer->ops != NULL && xfer->ops->c_poll != NULL);
1238 		xfer->ops->c_poll(chp, xfer);
1239 		ata_channel_lock(chp);
1240 		break;
1241 	case ATASTART_ABORT:
1242 		ata_channel_unlock(chp);
1243 		KASSERT(xfer->ops != NULL && xfer->ops->c_abort != NULL);
1244 		xfer->ops->c_abort(chp, xfer);
1245 		ata_channel_lock(chp);
1246 		break;
1247 	}
1248 
1249 	return rv;
1250 }
1251 
1252 static void
1253 ata_activate_xfer_locked(struct ata_channel *chp, struct ata_xfer *xfer)
1254 {
1255 	struct ata_queue * const chq = chp->ch_queue;
1256 
1257 	KASSERT(mutex_owned(&chp->ch_lock));
1258 	KASSERT((chq->active_xfers_used & __BIT(xfer->c_slot)) == 0);
1259 
1260 	if ((xfer->c_flags & C_SKIP_QUEUE) == 0)
1261 		TAILQ_INSERT_TAIL(&chq->active_xfers, xfer, c_activechain);
1262 	else {
1263 		/*
1264 		 * Must go to head, so that ata_queue_get_active_xfer()
1265 		 * returns the recovery command, and not some other
1266 		 * random active transfer.
1267 		 */
1268 		TAILQ_INSERT_HEAD(&chq->active_xfers, xfer, c_activechain);
1269 	}
1270 	chq->active_xfers_used |= __BIT(xfer->c_slot);
1271 	chq->queue_active++;
1272 }
1273 
1274 /*
1275  * Does it's own locking, does not require splbio().
1276  * flags - whether to block waiting for free xfer
1277  */
1278 struct ata_xfer *
1279 ata_get_xfer(struct ata_channel *chp, bool waitok)
1280 {
1281 	return pool_get(&ata_xfer_pool,
1282 	    PR_ZERO | (waitok ? PR_WAITOK : PR_NOWAIT));
1283 }
1284 
1285 /*
1286  * ata_deactivate_xfer() must be always called prior to ata_free_xfer()
1287  */
1288 void
1289 ata_free_xfer(struct ata_channel *chp, struct ata_xfer *xfer)
1290 {
1291 	struct ata_queue *chq = chp->ch_queue;
1292 
1293 	ata_channel_lock(chp);
1294 
1295 	if (__predict_false(xfer->c_flags & (C_WAITACT|C_WAITTIMO))) {
1296 		/* Someone is waiting for this xfer, so we can't free now */
1297 		xfer->c_flags |= C_FREE;
1298 		cv_broadcast(&chq->c_active);
1299 		ata_channel_unlock(chp);
1300 		return;
1301 	}
1302 
1303 	/* XXX move PIOBM and free_gw to deactivate? */
1304 #if NATA_PIOBM		/* XXX wdc dependent code */
1305 	if (__predict_false(xfer->c_flags & C_PIOBM)) {
1306 		struct wdc_softc *wdc = CHAN_TO_WDC(chp);
1307 
1308 		/* finish the busmastering PIO */
1309 		(*wdc->piobm_done)(wdc->dma_arg,
1310 		    chp->ch_channel, xfer->c_drive);
1311 		chp->ch_flags &= ~(ATACH_DMA_WAIT | ATACH_PIOBM_WAIT | ATACH_IRQ_WAIT);
1312 	}
1313 #endif
1314 
1315 	if (__predict_false(chp->ch_atac->atac_free_hw))
1316 		chp->ch_atac->atac_free_hw(chp);
1317 
1318 	ata_channel_unlock(chp);
1319 
1320 	if (__predict_true(!ISSET(xfer->c_flags, C_PRIVATE_ALLOC)))
1321 		pool_put(&ata_xfer_pool, xfer);
1322 }
1323 
1324 void
1325 ata_deactivate_xfer(struct ata_channel *chp, struct ata_xfer *xfer)
1326 {
1327 	struct ata_queue * const chq = chp->ch_queue;
1328 
1329 	ata_channel_lock(chp);
1330 
1331 	KASSERT(chq->queue_active > 0);
1332 	KASSERT((chq->active_xfers_used & __BIT(xfer->c_slot)) != 0);
1333 
1334 	/* Stop only when this is last active xfer */
1335 	if (chq->queue_active == 1)
1336 		callout_stop(&chp->c_timo_callout);
1337 
1338 	if (callout_invoking(&chp->c_timo_callout))
1339 		xfer->c_flags |= C_WAITTIMO;
1340 
1341 	TAILQ_REMOVE(&chq->active_xfers, xfer, c_activechain);
1342 	chq->active_xfers_used &= ~__BIT(xfer->c_slot);
1343 	chq->queue_active--;
1344 
1345 	ata_queue_free_slot(chp, xfer->c_slot);
1346 
1347 	if (xfer->c_flags & C_WAIT)
1348 		cv_broadcast(&chq->c_cmd_finish);
1349 
1350 	ata_channel_unlock(chp);
1351 }
1352 
1353 /*
1354  * Called in c_intr hook. Must be called before before any deactivations
1355  * are done - if there is drain pending, it calls c_kill_xfer hook which
1356  * deactivates the xfer.
1357  * Calls c_kill_xfer with channel lock free.
1358  * Returns true if caller should just exit without further processing.
1359  * Caller must not further access any part of xfer or any related controller
1360  * structures in that case, it should just return.
1361  */
1362 bool
1363 ata_waitdrain_xfer_check(struct ata_channel *chp, struct ata_xfer *xfer)
1364 {
1365 	int drive = xfer->c_drive;
1366 	bool draining = false;
1367 
1368 	ata_channel_lock(chp);
1369 
1370 	if (chp->ch_drive[drive].drive_flags & ATA_DRIVE_WAITDRAIN) {
1371 		ata_channel_unlock(chp);
1372 
1373 		xfer->ops->c_kill_xfer(chp, xfer, KILL_GONE);
1374 
1375 		ata_channel_lock(chp);
1376 		chp->ch_drive[drive].drive_flags &= ~ATA_DRIVE_WAITDRAIN;
1377 		cv_signal(&chp->ch_queue->queue_drain);
1378 		draining = true;
1379 	}
1380 
1381 	ata_channel_unlock(chp);
1382 
1383 	return draining;
1384 }
1385 
1386 /*
1387  * Check for race of normal transfer handling vs. timeout.
1388  */
1389 bool
1390 ata_timo_xfer_check(struct ata_xfer *xfer)
1391 {
1392 	struct ata_channel *chp = xfer->c_chp;
1393 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->c_drive];
1394 
1395 	ata_channel_lock(chp);
1396 
1397 	if (xfer->c_flags & C_WAITTIMO) {
1398 		xfer->c_flags &= ~C_WAITTIMO;
1399 
1400 		/* Handle race vs. ata_free_xfer() */
1401 		if (xfer->c_flags & C_FREE) {
1402 			xfer->c_flags &= ~C_FREE;
1403 			ata_channel_unlock(chp);
1404 
1405 	    		device_printf(drvp->drv_softc,
1406 			    "xfer %"PRIxPTR" freed while invoking timeout\n",
1407 			    (intptr_t)xfer & PAGE_MASK);
1408 
1409 			ata_free_xfer(chp, xfer);
1410 			return true;
1411 		}
1412 
1413 		/* Race vs. callout_stop() in ata_deactivate_xfer() */
1414 		ata_channel_unlock(chp);
1415 
1416 	    	device_printf(drvp->drv_softc,
1417 		    "xfer %"PRIxPTR" deactivated while invoking timeout\n",
1418 		    (intptr_t)xfer & PAGE_MASK);
1419 		return true;
1420 	}
1421 
1422 	ata_channel_unlock(chp);
1423 
1424 	/* No race, proceed with timeout handling */
1425 	return false;
1426 }
1427 
1428 /*
1429  * Kill off all active xfers for a ata_channel.
1430  *
1431  * Must be called with channel lock held.
1432  */
1433 void
1434 ata_kill_active(struct ata_channel *chp, int reason, int flags)
1435 {
1436 	struct ata_queue * const chq = chp->ch_queue;
1437 	struct ata_xfer *xfer, *xfernext;
1438 
1439 	KASSERT(mutex_owned(&chp->ch_lock));
1440 
1441 	TAILQ_FOREACH_SAFE(xfer, &chq->active_xfers, c_activechain, xfernext) {
1442 		ata_channel_unlock(chp);
1443 		xfer->ops->c_kill_xfer(xfer->c_chp, xfer, reason);
1444 		ata_channel_lock(chp);
1445 	}
1446 }
1447 
1448 /*
1449  * Kill off all pending xfers for a drive.
1450  */
1451 void
1452 ata_kill_pending(struct ata_drive_datas *drvp)
1453 {
1454 	struct ata_channel * const chp = drvp->chnl_softc;
1455 	struct ata_queue * const chq = chp->ch_queue;
1456 	struct ata_xfer *xfer;
1457 
1458 	ata_channel_lock(chp);
1459 
1460 	/* Kill all pending transfers */
1461 	while ((xfer = SIMPLEQ_FIRST(&chq->queue_xfer))) {
1462 		KASSERT(xfer->c_chp == chp);
1463 
1464 		if (xfer->c_drive != drvp->drive)
1465 			continue;
1466 
1467 		SIMPLEQ_REMOVE_HEAD(&chp->ch_queue->queue_xfer, c_xferchain);
1468 
1469 		/*
1470 		 * Keep the lock, so that we get deadlock (and 'locking against
1471 		 * myself' with LOCKDEBUG), instead of silent
1472 		 * data corruption, if the hook tries to call back into
1473 		 * middle layer for inactive xfer.
1474 		 */
1475 		xfer->ops->c_kill_xfer(chp, xfer, KILL_GONE_INACTIVE);
1476 	}
1477 
1478 	/* Wait until all active transfers on the drive finish */
1479 	while (chq->queue_active > 0) {
1480 		bool drv_active = false;
1481 
1482 		TAILQ_FOREACH(xfer, &chq->active_xfers, c_activechain) {
1483 			KASSERT(xfer->c_chp == chp);
1484 
1485 			if (xfer->c_drive == drvp->drive) {
1486 				drv_active = true;
1487 				break;
1488 			}
1489 		}
1490 
1491 		if (!drv_active) {
1492 			/* all finished */
1493 			break;
1494 		}
1495 
1496 		drvp->drive_flags |= ATA_DRIVE_WAITDRAIN;
1497 		cv_wait(&chq->queue_drain, &chp->ch_lock);
1498 	}
1499 
1500 	ata_channel_unlock(chp);
1501 }
1502 
1503 static void
1504 ata_channel_freeze_locked(struct ata_channel *chp)
1505 {
1506 	chp->ch_queue->queue_freeze++;
1507 
1508 	ATADEBUG_PRINT(("%s(chp=%p) -> %d\n", __func__, chp,
1509 	    chp->ch_queue->queue_freeze), DEBUG_FUNCS | DEBUG_XFERS);
1510 }
1511 
1512 void
1513 ata_channel_freeze(struct ata_channel *chp)
1514 {
1515 	ata_channel_lock(chp);
1516 	ata_channel_freeze_locked(chp);
1517 	ata_channel_unlock(chp);
1518 }
1519 
1520 void
1521 ata_channel_thaw_locked(struct ata_channel *chp)
1522 {
1523 	KASSERT(mutex_owned(&chp->ch_lock));
1524 	KASSERT(chp->ch_queue->queue_freeze > 0);
1525 
1526 	chp->ch_queue->queue_freeze--;
1527 
1528 	ATADEBUG_PRINT(("%s(chp=%p) -> %d\n", __func__, chp,
1529 	    chp->ch_queue->queue_freeze), DEBUG_FUNCS | DEBUG_XFERS);
1530 }
1531 
1532 /*
1533  * ata_thread_run:
1534  *
1535  *	Reset and ATA channel. Channel lock must be held. arg is type-specific.
1536  */
1537 void
1538 ata_thread_run(struct ata_channel *chp, int flags, int type, int arg)
1539 {
1540 	struct atac_softc *atac = chp->ch_atac;
1541 	bool threset = false;
1542 	struct ata_drive_datas *drvp;
1543 
1544 	ata_channel_lock_owned(chp);
1545 
1546 	/*
1547 	 * If we can poll or wait it's OK, otherwise wake up the
1548 	 * kernel thread to do it for us.
1549 	 */
1550 	ATADEBUG_PRINT(("%s flags 0x%x ch_flags 0x%x\n",
1551 	    __func__, flags, chp->ch_flags), DEBUG_FUNCS | DEBUG_XFERS);
1552 	if ((flags & (AT_POLL | AT_WAIT)) == 0) {
1553 		switch (type) {
1554 		case ATACH_TH_RESET:
1555 			if (chp->ch_flags & ATACH_TH_RESET) {
1556 				/* No need to schedule another reset */
1557 				return;
1558 			}
1559 			break;
1560 		case ATACH_TH_DRIVE_RESET:
1561 		    {
1562 			int drive = arg;
1563 
1564 			KASSERT(drive <= chp->ch_ndrives);
1565 			drvp = &chp->ch_drive[drive];
1566 
1567 			if (drvp->drive_flags & ATA_DRIVE_TH_RESET) {
1568 				/* No need to schedule another reset */
1569 				return;
1570 			}
1571 			drvp->drive_flags |= ATA_DRIVE_TH_RESET;
1572 			break;
1573 		    }
1574 		case ATACH_TH_RECOVERY:
1575 		    {
1576 			uint32_t tfd = (uint32_t)arg;
1577 
1578 			KASSERT((chp->ch_flags & ATACH_RECOVERING) == 0);
1579 			chp->recovery_tfd = tfd;
1580 			break;
1581 		    }
1582 		default:
1583 			panic("%s: unknown type: %x", __func__, type);
1584 			/* NOTREACHED */
1585 		}
1586 
1587 		/*
1588 		 * Block execution of other commands while reset is scheduled
1589 		 * to a thread.
1590 		 */
1591 		ata_channel_freeze_locked(chp);
1592 		chp->ch_flags |= type;
1593 
1594 		cv_signal(&chp->ch_thr_idle);
1595 		return;
1596 	}
1597 
1598 	/* Block execution of other commands during reset */
1599 	ata_channel_freeze_locked(chp);
1600 
1601 	/*
1602 	 * If reset has been scheduled to a thread, then clear
1603 	 * the flag now so that the thread won't try to execute it if
1604 	 * we happen to sleep, and thaw one more time after the reset.
1605 	 */
1606 	if (chp->ch_flags & type) {
1607 		chp->ch_flags &= ~type;
1608 		threset = true;
1609 	}
1610 
1611 	switch (type) {
1612 	case ATACH_TH_RESET:
1613 		(*atac->atac_bustype_ata->ata_reset_channel)(chp, flags);
1614 
1615 		KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
1616 		for (int drive = 0; drive < chp->ch_ndrives; drive++)
1617 			chp->ch_drive[drive].state = 0;
1618 		break;
1619 
1620 	case ATACH_TH_DRIVE_RESET:
1621 	    {
1622 		int drive = arg;
1623 
1624 		KASSERT(drive <= chp->ch_ndrives);
1625 		drvp = &chp->ch_drive[drive];
1626 		(*atac->atac_bustype_ata->ata_reset_drive)(drvp, flags, NULL);
1627 		drvp->state = 0;
1628 		break;
1629 	    }
1630 
1631 	case ATACH_TH_RECOVERY:
1632 	    {
1633 		uint32_t tfd = (uint32_t)arg;
1634 
1635 		KASSERT((chp->ch_flags & ATACH_RECOVERING) == 0);
1636 		KASSERT(atac->atac_bustype_ata->ata_recovery != NULL);
1637 
1638 		SET(chp->ch_flags, ATACH_RECOVERING);
1639 		(*atac->atac_bustype_ata->ata_recovery)(chp, flags, tfd);
1640 		CLR(chp->ch_flags, ATACH_RECOVERING);
1641 		break;
1642 	    }
1643 
1644 	default:
1645 		panic("%s: unknown type: %x", __func__, type);
1646 		/* NOTREACHED */
1647 	}
1648 
1649 	/*
1650 	 * Thaw one extra time to clear the freeze done when the reset has
1651 	 * been scheduled to the thread.
1652 	 */
1653 	if (threset)
1654 		ata_channel_thaw_locked(chp);
1655 
1656 	/* Allow commands to run again */
1657 	ata_channel_thaw_locked(chp);
1658 
1659 	/* Signal the thread in case there is an xfer to run */
1660 	cv_signal(&chp->ch_thr_idle);
1661 }
1662 
1663 int
1664 ata_addref(struct ata_channel *chp)
1665 {
1666 	struct atac_softc *atac = chp->ch_atac;
1667 	struct scsipi_adapter *adapt = &atac->atac_atapi_adapter._generic;
1668 	int s, error = 0;
1669 
1670 	s = splbio();
1671 	if (adapt->adapt_refcnt++ == 0 &&
1672 	    adapt->adapt_enable != NULL) {
1673 		error = (*adapt->adapt_enable)(atac->atac_dev, 1);
1674 		if (error)
1675 			adapt->adapt_refcnt--;
1676 	}
1677 	splx(s);
1678 	return (error);
1679 }
1680 
1681 void
1682 ata_delref(struct ata_channel *chp)
1683 {
1684 	struct atac_softc *atac = chp->ch_atac;
1685 	struct scsipi_adapter *adapt = &atac->atac_atapi_adapter._generic;
1686 	int s;
1687 
1688 	s = splbio();
1689 	if (adapt->adapt_refcnt-- == 1 &&
1690 	    adapt->adapt_enable != NULL)
1691 		(void) (*adapt->adapt_enable)(atac->atac_dev, 0);
1692 	splx(s);
1693 }
1694 
1695 void
1696 ata_print_modes(struct ata_channel *chp)
1697 {
1698 	struct atac_softc *atac = chp->ch_atac;
1699 	int drive;
1700 	struct ata_drive_datas *drvp;
1701 
1702 	KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
1703 	for (drive = 0; drive < chp->ch_ndrives; drive++) {
1704 		drvp = &chp->ch_drive[drive];
1705 		if (drvp->drive_type == ATA_DRIVET_NONE ||
1706 		    drvp->drv_softc == NULL)
1707 			continue;
1708 		aprint_verbose("%s(%s:%d:%d): using PIO mode %d",
1709 			device_xname(drvp->drv_softc),
1710 			device_xname(atac->atac_dev),
1711 			chp->ch_channel, drvp->drive, drvp->PIO_mode);
1712 #if NATA_DMA
1713 		if (drvp->drive_flags & ATA_DRIVE_DMA)
1714 			aprint_verbose(", DMA mode %d", drvp->DMA_mode);
1715 #if NATA_UDMA
1716 		if (drvp->drive_flags & ATA_DRIVE_UDMA) {
1717 			aprint_verbose(", Ultra-DMA mode %d", drvp->UDMA_mode);
1718 			if (drvp->UDMA_mode == 2)
1719 				aprint_verbose(" (Ultra/33)");
1720 			else if (drvp->UDMA_mode == 4)
1721 				aprint_verbose(" (Ultra/66)");
1722 			else if (drvp->UDMA_mode == 5)
1723 				aprint_verbose(" (Ultra/100)");
1724 			else if (drvp->UDMA_mode == 6)
1725 				aprint_verbose(" (Ultra/133)");
1726 		}
1727 #endif	/* NATA_UDMA */
1728 #endif	/* NATA_DMA */
1729 #if NATA_DMA || NATA_PIOBM
1730 		if (0
1731 #if NATA_DMA
1732 		    || (drvp->drive_flags & (ATA_DRIVE_DMA | ATA_DRIVE_UDMA))
1733 #endif
1734 #if NATA_PIOBM
1735 		    /* PIOBM capable controllers use DMA for PIO commands */
1736 		    || (atac->atac_cap & ATAC_CAP_PIOBM)
1737 #endif
1738 		    )
1739 			aprint_verbose(" (using DMA)");
1740 
1741 		if (drvp->drive_flags & ATA_DRIVE_NCQ) {
1742 			aprint_verbose(", NCQ (%d tags)%s",
1743 			    ATA_REAL_OPENINGS(chp->ch_queue->queue_openings),
1744 			    (drvp->drive_flags & ATA_DRIVE_NCQ_PRIO)
1745 			    ? " w/PRIO" : "");
1746 		} else if (drvp->drive_flags & ATA_DRIVE_WFUA)
1747 			aprint_verbose(", WRITE DMA FUA EXT");
1748 
1749 #endif	/* NATA_DMA || NATA_PIOBM */
1750 		aprint_verbose("\n");
1751 	}
1752 }
1753 
1754 #if NATA_DMA
1755 /*
1756  * downgrade the transfer mode of a drive after an error. return 1 if
1757  * downgrade was possible, 0 otherwise.
1758  *
1759  * MUST BE CALLED AT splbio()!
1760  */
1761 int
1762 ata_downgrade_mode(struct ata_drive_datas *drvp, int flags)
1763 {
1764 	struct ata_channel *chp = drvp->chnl_softc;
1765 	struct atac_softc *atac = chp->ch_atac;
1766 	device_t drv_dev = drvp->drv_softc;
1767 	int cf_flags = device_cfdata(drv_dev)->cf_flags;
1768 
1769 	ata_channel_lock_owned(drvp->chnl_softc);
1770 
1771 	/* if drive or controller don't know its mode, we can't do much */
1772 	if ((drvp->drive_flags & ATA_DRIVE_MODE) == 0 ||
1773 	    (atac->atac_set_modes == NULL))
1774 		return 0;
1775 	/* current drive mode was set by a config flag, let it this way */
1776 	if ((cf_flags & ATA_CONFIG_PIO_SET) ||
1777 	    (cf_flags & ATA_CONFIG_DMA_SET) ||
1778 	    (cf_flags & ATA_CONFIG_UDMA_SET))
1779 		return 0;
1780 
1781 #if NATA_UDMA
1782 	/*
1783 	 * If we were using Ultra-DMA mode, downgrade to the next lower mode.
1784 	 */
1785 	if ((drvp->drive_flags & ATA_DRIVE_UDMA) && drvp->UDMA_mode >= 2) {
1786 		drvp->UDMA_mode--;
1787 		aprint_error_dev(drv_dev,
1788 		    "transfer error, downgrading to Ultra-DMA mode %d\n",
1789 		    drvp->UDMA_mode);
1790 	}
1791 #endif
1792 
1793 	/*
1794 	 * If we were using ultra-DMA, don't downgrade to multiword DMA.
1795 	 */
1796 	else if (drvp->drive_flags & (ATA_DRIVE_DMA | ATA_DRIVE_UDMA)) {
1797 		drvp->drive_flags &= ~(ATA_DRIVE_DMA | ATA_DRIVE_UDMA);
1798 		drvp->PIO_mode = drvp->PIO_cap;
1799 		aprint_error_dev(drv_dev,
1800 		    "transfer error, downgrading to PIO mode %d\n",
1801 		    drvp->PIO_mode);
1802 	} else /* already using PIO, can't downgrade */
1803 		return 0;
1804 
1805 	(*atac->atac_set_modes)(chp);
1806 	ata_print_modes(chp);
1807 	/* reset the channel, which will schedule all drives for setup */
1808 	ata_thread_run(chp, flags, ATACH_TH_RESET, ATACH_NODRIVE);
1809 	return 1;
1810 }
1811 #endif	/* NATA_DMA */
1812 
1813 /*
1814  * Probe drive's capabilities, for use by the controller later
1815  * Assumes drvp points to an existing drive.
1816  */
1817 void
1818 ata_probe_caps(struct ata_drive_datas *drvp)
1819 {
1820 	struct ataparams params, params2;
1821 	struct ata_channel *chp = drvp->chnl_softc;
1822 	struct atac_softc *atac = chp->ch_atac;
1823 	device_t drv_dev = drvp->drv_softc;
1824 	int i, printed = 0;
1825 	const char *sep = "";
1826 	int cf_flags;
1827 
1828 	if (ata_get_params(drvp, AT_WAIT, &params) != CMD_OK) {
1829 		/* IDENTIFY failed. Can't tell more about the device */
1830 		return;
1831 	}
1832 	if ((atac->atac_cap & (ATAC_CAP_DATA16 | ATAC_CAP_DATA32)) ==
1833 	    (ATAC_CAP_DATA16 | ATAC_CAP_DATA32)) {
1834 		/*
1835 		 * Controller claims 16 and 32 bit transfers.
1836 		 * Re-do an IDENTIFY with 32-bit transfers,
1837 		 * and compare results.
1838 		 */
1839 		ata_channel_lock(chp);
1840 		drvp->drive_flags |= ATA_DRIVE_CAP32;
1841 		ata_channel_unlock(chp);
1842 		ata_get_params(drvp, AT_WAIT, &params2);
1843 		if (memcmp(&params, &params2, sizeof(struct ataparams)) != 0) {
1844 			/* Not good. fall back to 16bits */
1845 			ata_channel_lock(chp);
1846 			drvp->drive_flags &= ~ATA_DRIVE_CAP32;
1847 			ata_channel_unlock(chp);
1848 		} else {
1849 			aprint_verbose_dev(drv_dev, "32-bit data port\n");
1850 		}
1851 	}
1852 #if 0 /* Some ultra-DMA drives claims to only support ATA-3. sigh */
1853 	if (params.atap_ata_major > 0x01 &&
1854 	    params.atap_ata_major != 0xffff) {
1855 		for (i = 14; i > 0; i--) {
1856 			if (params.atap_ata_major & (1 << i)) {
1857 				aprint_verbose_dev(drv_dev,
1858 				    "ATA version %d\n", i);
1859 				drvp->ata_vers = i;
1860 				break;
1861 			}
1862 		}
1863 	}
1864 #endif
1865 
1866 	/* An ATAPI device is at last PIO mode 3 */
1867 	if (drvp->drive_type == ATA_DRIVET_ATAPI)
1868 		drvp->PIO_mode = 3;
1869 
1870 	/*
1871 	 * It's not in the specs, but it seems that some drive
1872 	 * returns 0xffff in atap_extensions when this field is invalid
1873 	 */
1874 	if (params.atap_extensions != 0xffff &&
1875 	    (params.atap_extensions & WDC_EXT_MODES)) {
1876 		/*
1877 		 * XXX some drives report something wrong here (they claim to
1878 		 * support PIO mode 8 !). As mode is coded on 3 bits in
1879 		 * SET FEATURE, limit it to 7 (so limit i to 4).
1880 		 * If higher mode than 7 is found, abort.
1881 		 */
1882 		for (i = 7; i >= 0; i--) {
1883 			if ((params.atap_piomode_supp & (1 << i)) == 0)
1884 				continue;
1885 			if (i > 4)
1886 				return;
1887 			/*
1888 			 * See if mode is accepted.
1889 			 * If the controller can't set its PIO mode,
1890 			 * assume the defaults are good, so don't try
1891 			 * to set it
1892 			 */
1893 			if (atac->atac_set_modes)
1894 				/*
1895 				 * It's OK to pool here, it's fast enough
1896 				 * to not bother waiting for interrupt
1897 				 */
1898 				if (ata_set_mode(drvp, 0x08 | (i + 3),
1899 				   AT_WAIT) != CMD_OK)
1900 					continue;
1901 			if (!printed) {
1902 				aprint_verbose_dev(drv_dev,
1903 				    "drive supports PIO mode %d", i + 3);
1904 				sep = ",";
1905 				printed = 1;
1906 			}
1907 			/*
1908 			 * If controller's driver can't set its PIO mode,
1909 			 * get the highter one for the drive.
1910 			 */
1911 			if (atac->atac_set_modes == NULL ||
1912 			    atac->atac_pio_cap >= i + 3) {
1913 				drvp->PIO_mode = i + 3;
1914 				drvp->PIO_cap = i + 3;
1915 				break;
1916 			}
1917 		}
1918 		if (!printed) {
1919 			/*
1920 			 * We didn't find a valid PIO mode.
1921 			 * Assume the values returned for DMA are buggy too
1922 			 */
1923 			return;
1924 		}
1925 		ata_channel_lock(chp);
1926 		drvp->drive_flags |= ATA_DRIVE_MODE;
1927 		ata_channel_unlock(chp);
1928 		printed = 0;
1929 		for (i = 7; i >= 0; i--) {
1930 			if ((params.atap_dmamode_supp & (1 << i)) == 0)
1931 				continue;
1932 #if NATA_DMA
1933 			if ((atac->atac_cap & ATAC_CAP_DMA) &&
1934 			    atac->atac_set_modes != NULL)
1935 				if (ata_set_mode(drvp, 0x20 | i, AT_WAIT)
1936 				    != CMD_OK)
1937 					continue;
1938 #endif
1939 			if (!printed) {
1940 				aprint_verbose("%s DMA mode %d", sep, i);
1941 				sep = ",";
1942 				printed = 1;
1943 			}
1944 #if NATA_DMA
1945 			if (atac->atac_cap & ATAC_CAP_DMA) {
1946 				if (atac->atac_set_modes != NULL &&
1947 				    atac->atac_dma_cap < i)
1948 					continue;
1949 				drvp->DMA_mode = i;
1950 				drvp->DMA_cap = i;
1951 				ata_channel_lock(chp);
1952 				drvp->drive_flags |= ATA_DRIVE_DMA;
1953 				ata_channel_unlock(chp);
1954 			}
1955 #endif
1956 			break;
1957 		}
1958 		if (params.atap_extensions & WDC_EXT_UDMA_MODES) {
1959 			printed = 0;
1960 			for (i = 7; i >= 0; i--) {
1961 				if ((params.atap_udmamode_supp & (1 << i))
1962 				    == 0)
1963 					continue;
1964 #if NATA_UDMA
1965 				if (atac->atac_set_modes != NULL &&
1966 				    (atac->atac_cap & ATAC_CAP_UDMA))
1967 					if (ata_set_mode(drvp, 0x40 | i,
1968 					    AT_WAIT) != CMD_OK)
1969 						continue;
1970 #endif
1971 				if (!printed) {
1972 					aprint_verbose("%s Ultra-DMA mode %d",
1973 					    sep, i);
1974 					if (i == 2)
1975 						aprint_verbose(" (Ultra/33)");
1976 					else if (i == 4)
1977 						aprint_verbose(" (Ultra/66)");
1978 					else if (i == 5)
1979 						aprint_verbose(" (Ultra/100)");
1980 					else if (i == 6)
1981 						aprint_verbose(" (Ultra/133)");
1982 					sep = ",";
1983 					printed = 1;
1984 				}
1985 #if NATA_UDMA
1986 				if (atac->atac_cap & ATAC_CAP_UDMA) {
1987 					if (atac->atac_set_modes != NULL &&
1988 					    atac->atac_udma_cap < i)
1989 						continue;
1990 					drvp->UDMA_mode = i;
1991 					drvp->UDMA_cap = i;
1992 					ata_channel_lock(chp);
1993 					drvp->drive_flags |= ATA_DRIVE_UDMA;
1994 					ata_channel_unlock(chp);
1995 				}
1996 #endif
1997 				break;
1998 			}
1999 		}
2000 	}
2001 
2002 	ata_channel_lock(chp);
2003 	drvp->drive_flags &= ~ATA_DRIVE_NOSTREAM;
2004 	if (drvp->drive_type == ATA_DRIVET_ATAPI) {
2005 		if (atac->atac_cap & ATAC_CAP_ATAPI_NOSTREAM)
2006 			drvp->drive_flags |= ATA_DRIVE_NOSTREAM;
2007 	} else {
2008 		if (atac->atac_cap & ATAC_CAP_ATA_NOSTREAM)
2009 			drvp->drive_flags |= ATA_DRIVE_NOSTREAM;
2010 	}
2011 	ata_channel_unlock(chp);
2012 
2013 	/* Try to guess ATA version here, if it didn't get reported */
2014 	if (drvp->ata_vers == 0) {
2015 #if NATA_UDMA
2016 		if (drvp->drive_flags & ATA_DRIVE_UDMA)
2017 			drvp->ata_vers = 4; /* should be at last ATA-4 */
2018 		else
2019 #endif
2020 		if (drvp->PIO_cap > 2)
2021 			drvp->ata_vers = 2; /* should be at last ATA-2 */
2022 	}
2023 	cf_flags = device_cfdata(drv_dev)->cf_flags;
2024 	if (cf_flags & ATA_CONFIG_PIO_SET) {
2025 		ata_channel_lock(chp);
2026 		drvp->PIO_mode =
2027 		    (cf_flags & ATA_CONFIG_PIO_MODES) >> ATA_CONFIG_PIO_OFF;
2028 		drvp->drive_flags |= ATA_DRIVE_MODE;
2029 		ata_channel_unlock(chp);
2030 	}
2031 #if NATA_DMA
2032 	if ((atac->atac_cap & ATAC_CAP_DMA) == 0) {
2033 		/* don't care about DMA modes */
2034 		if (*sep != '\0')
2035 			aprint_verbose("\n");
2036 		return;
2037 	}
2038 	if (cf_flags & ATA_CONFIG_DMA_SET) {
2039 		ata_channel_lock(chp);
2040 		if ((cf_flags & ATA_CONFIG_DMA_MODES) ==
2041 		    ATA_CONFIG_DMA_DISABLE) {
2042 			drvp->drive_flags &= ~ATA_DRIVE_DMA;
2043 		} else {
2044 			drvp->DMA_mode = (cf_flags & ATA_CONFIG_DMA_MODES) >>
2045 			    ATA_CONFIG_DMA_OFF;
2046 			drvp->drive_flags |= ATA_DRIVE_DMA | ATA_DRIVE_MODE;
2047 		}
2048 		ata_channel_unlock(chp);
2049 	}
2050 
2051 	/*
2052 	 * Probe WRITE DMA FUA EXT. Support is mandatory for devices
2053 	 * supporting LBA48, but nevertheless confirm with the feature flag.
2054 	 */
2055 	if (drvp->drive_flags & ATA_DRIVE_DMA) {
2056 		if ((params.atap_cmd2_en & ATA_CMD2_LBA48) != 0
2057 		    && (params.atap_cmd_def & ATA_CMDE_WFE)) {
2058 			drvp->drive_flags |= ATA_DRIVE_WFUA;
2059 			aprint_verbose("%s WRITE DMA FUA", sep);
2060 			sep = ",";
2061 		}
2062 	}
2063 
2064 	/* Probe NCQ support - READ/WRITE FPDMA QUEUED command support */
2065 	ata_channel_lock(chp);
2066 	drvp->drv_openings = 1;
2067 	if (params.atap_sata_caps & SATA_NATIVE_CMDQ) {
2068 		if (atac->atac_cap & ATAC_CAP_NCQ)
2069 			drvp->drive_flags |= ATA_DRIVE_NCQ;
2070 		drvp->drv_openings =
2071 		    (params.atap_queuedepth & WDC_QUEUE_DEPTH_MASK) + 1;
2072 		aprint_verbose("%s NCQ (%d tags)", sep, drvp->drv_openings);
2073 		sep = ",";
2074 
2075 		if (params.atap_sata_caps & SATA_NCQ_PRIO) {
2076 			drvp->drive_flags |= ATA_DRIVE_NCQ_PRIO;
2077 			aprint_verbose(" w/PRIO");
2078 		}
2079 	}
2080 	ata_channel_unlock(chp);
2081 
2082 	if (*sep != '\0')
2083 		aprint_verbose("\n");
2084 
2085 #if NATA_UDMA
2086 	if ((atac->atac_cap & ATAC_CAP_UDMA) == 0) {
2087 		/* don't care about UDMA modes */
2088 		return;
2089 	}
2090 	if (cf_flags & ATA_CONFIG_UDMA_SET) {
2091 		ata_channel_lock(chp);
2092 		if ((cf_flags & ATA_CONFIG_UDMA_MODES) ==
2093 		    ATA_CONFIG_UDMA_DISABLE) {
2094 			drvp->drive_flags &= ~ATA_DRIVE_UDMA;
2095 		} else {
2096 			drvp->UDMA_mode = (cf_flags & ATA_CONFIG_UDMA_MODES) >>
2097 			    ATA_CONFIG_UDMA_OFF;
2098 			drvp->drive_flags |= ATA_DRIVE_UDMA | ATA_DRIVE_MODE;
2099 		}
2100 		ata_channel_unlock(chp);
2101 	}
2102 #endif	/* NATA_UDMA */
2103 #endif	/* NATA_DMA */
2104 }
2105 
2106 /* management of the /dev/atabus* devices */
2107 int
2108 atabusopen(dev_t dev, int flag, int fmt, struct lwp *l)
2109 {
2110 	struct atabus_softc *sc;
2111 	int error;
2112 
2113 	sc = device_lookup_private(&atabus_cd, minor(dev));
2114 	if (sc == NULL)
2115 		return (ENXIO);
2116 
2117 	if (sc->sc_flags & ATABUSCF_OPEN)
2118 		return (EBUSY);
2119 
2120 	if ((error = ata_addref(sc->sc_chan)) != 0)
2121 		return (error);
2122 
2123 	sc->sc_flags |= ATABUSCF_OPEN;
2124 
2125 	return (0);
2126 }
2127 
2128 
2129 int
2130 atabusclose(dev_t dev, int flag, int fmt, struct lwp *l)
2131 {
2132 	struct atabus_softc *sc =
2133 	    device_lookup_private(&atabus_cd, minor(dev));
2134 
2135 	ata_delref(sc->sc_chan);
2136 
2137 	sc->sc_flags &= ~ATABUSCF_OPEN;
2138 
2139 	return (0);
2140 }
2141 
2142 int
2143 atabusioctl(dev_t dev, u_long cmd, void *addr, int flag, struct lwp *l)
2144 {
2145 	struct atabus_softc *sc =
2146 	    device_lookup_private(&atabus_cd, minor(dev));
2147 	struct ata_channel *chp = sc->sc_chan;
2148 	int min_drive, max_drive, drive;
2149 	int error;
2150 
2151 	/*
2152 	 * Enforce write permission for ioctls that change the
2153 	 * state of the bus.  Host adapter specific ioctls must
2154 	 * be checked by the adapter driver.
2155 	 */
2156 	switch (cmd) {
2157 	case ATABUSIOSCAN:
2158 	case ATABUSIODETACH:
2159 	case ATABUSIORESET:
2160 		if ((flag & FWRITE) == 0)
2161 			return (EBADF);
2162 	}
2163 
2164 	switch (cmd) {
2165 	case ATABUSIORESET:
2166 		ata_channel_lock(chp);
2167 		ata_thread_run(sc->sc_chan, AT_WAIT | AT_POLL,
2168 		    ATACH_TH_RESET, ATACH_NODRIVE);
2169 		ata_channel_unlock(chp);
2170 		return 0;
2171 	case ATABUSIOSCAN:
2172 	{
2173 #if 0
2174 		struct atabusioscan_args *a=
2175 		    (struct atabusioscan_args *)addr;
2176 #endif
2177 		if ((chp->ch_drive[0].drive_type == ATA_DRIVET_OLD) ||
2178 		    (chp->ch_drive[1].drive_type == ATA_DRIVET_OLD))
2179 			return (EOPNOTSUPP);
2180 		return (EOPNOTSUPP);
2181 	}
2182 	case ATABUSIODETACH:
2183 	{
2184 		struct atabusiodetach_args *a=
2185 		    (struct atabusiodetach_args *)addr;
2186 		if ((chp->ch_drive[0].drive_type == ATA_DRIVET_OLD) ||
2187 		    (chp->ch_drive[1].drive_type == ATA_DRIVET_OLD))
2188 			return (EOPNOTSUPP);
2189 		switch (a->at_dev) {
2190 		case -1:
2191 			min_drive = 0;
2192 			max_drive = 1;
2193 			break;
2194 		case 0:
2195 		case 1:
2196 			min_drive = max_drive = a->at_dev;
2197 			break;
2198 		default:
2199 			return (EINVAL);
2200 		}
2201 		for (drive = min_drive; drive <= max_drive; drive++) {
2202 			if (chp->ch_drive[drive].drv_softc != NULL) {
2203 				error = config_detach(
2204 				    chp->ch_drive[drive].drv_softc, 0);
2205 				if (error)
2206 					return (error);
2207 				KASSERT(chp->ch_drive[drive].drv_softc == NULL);
2208 			}
2209 		}
2210 		return 0;
2211 	}
2212 	default:
2213 		return ENOTTY;
2214 	}
2215 }
2216 
2217 static bool
2218 atabus_suspend(device_t dv, const pmf_qual_t *qual)
2219 {
2220 	struct atabus_softc *sc = device_private(dv);
2221 	struct ata_channel *chp = sc->sc_chan;
2222 
2223 	ata_channel_idle(chp);
2224 
2225 	return true;
2226 }
2227 
2228 static bool
2229 atabus_resume(device_t dv, const pmf_qual_t *qual)
2230 {
2231 	struct atabus_softc *sc = device_private(dv);
2232 	struct ata_channel *chp = sc->sc_chan;
2233 
2234 	/*
2235 	 * XXX joerg: with wdc, the first channel unfreezes the controler.
2236 	 * Move this the reset and queue idling into wdc.
2237 	 */
2238 	ata_channel_lock(chp);
2239 	if (chp->ch_queue->queue_freeze == 0) {
2240 		ata_channel_unlock(chp);
2241 		goto out;
2242 	}
2243 
2244 	/* unfreeze the queue and reset drives */
2245 	ata_channel_thaw_locked(chp);
2246 
2247 	/* reset channel only if there are drives attached */
2248 	if (chp->ch_ndrives > 0)
2249 		ata_thread_run(chp, AT_WAIT, ATACH_TH_RESET, ATACH_NODRIVE);
2250 
2251 	ata_channel_unlock(chp);
2252 
2253 out:
2254 	return true;
2255 }
2256 
2257 static int
2258 atabus_rescan(device_t self, const char *ifattr, const int *locators)
2259 {
2260 	struct atabus_softc *sc = device_private(self);
2261 	struct ata_channel *chp = sc->sc_chan;
2262 	struct atabus_initq *initq;
2263 	int i;
2264 
2265 	/*
2266 	 * we can rescan a port multiplier atabus, even if some devices are
2267 	 * still attached
2268 	 */
2269 	if (chp->ch_satapmp_nports == 0) {
2270 		if (chp->atapibus != NULL) {
2271 			return EBUSY;
2272 		}
2273 
2274 		KASSERT(chp->ch_ndrives == 0 || chp->ch_drive != NULL);
2275 		for (i = 0; i < chp->ch_ndrives; i++) {
2276 			if (chp->ch_drive[i].drv_softc != NULL) {
2277 				return EBUSY;
2278 			}
2279 		}
2280 	}
2281 
2282 	initq = kmem_zalloc(sizeof(*initq), KM_SLEEP);
2283 	initq->atabus_sc = sc;
2284 	mutex_enter(&atabus_qlock);
2285 	TAILQ_INSERT_TAIL(&atabus_initq_head, initq, atabus_initq);
2286 	mutex_exit(&atabus_qlock);
2287 	config_pending_incr(sc->sc_dev);
2288 
2289 	ata_channel_lock(chp);
2290 	chp->ch_flags |= ATACH_TH_RESCAN;
2291 	cv_signal(&chp->ch_thr_idle);
2292 	ata_channel_unlock(chp);
2293 
2294 	return 0;
2295 }
2296 
2297 void
2298 ata_delay(struct ata_channel *chp, int ms, const char *msg, int flags)
2299 {
2300 	KASSERT(mutex_owned(&chp->ch_lock));
2301 
2302 	if ((flags & (AT_WAIT | AT_POLL)) == AT_POLL) {
2303 		/*
2304 		 * can't use kpause(), we may be in interrupt context
2305 		 * or taking a crash dump
2306 		 */
2307 		delay(ms * 1000);
2308 	} else {
2309 		int pause = mstohz(ms);
2310 
2311 		kpause(msg, false, pause > 0 ? pause : 1, &chp->ch_lock);
2312 	}
2313 }
2314 
2315 void
2316 atacmd_toncq(struct ata_xfer *xfer, uint8_t *cmd, uint16_t *count,
2317     uint16_t *features, uint8_t *device)
2318 {
2319 	if ((xfer->c_flags & C_NCQ) == 0) {
2320 		/* FUA handling for non-NCQ drives */
2321 		if (xfer->c_bio.flags & ATA_FUA
2322 		    && *cmd == WDCC_WRITEDMA_EXT)
2323 			*cmd = WDCC_WRITEDMA_FUA_EXT;
2324 
2325 		return;
2326 	}
2327 
2328 	*cmd = (xfer->c_bio.flags & ATA_READ) ?
2329 	    WDCC_READ_FPDMA_QUEUED : WDCC_WRITE_FPDMA_QUEUED;
2330 
2331 	/* for FPDMA the block count is in features */
2332 	*features = *count;
2333 
2334 	/* NCQ tag */
2335 	*count = (xfer->c_slot << 3);
2336 
2337 	if (xfer->c_bio.flags & ATA_PRIO_HIGH)
2338 		*count |= WDSC_PRIO_HIGH;
2339 
2340 	/* other device flags */
2341 	if (xfer->c_bio.flags & ATA_FUA)
2342 		*device |= WDSD_FUA;
2343 }
2344 
2345 void
2346 ata_wait_cmd(struct ata_channel *chp, struct ata_xfer *xfer)
2347 {
2348 	struct ata_queue *chq = chp->ch_queue;
2349 	struct ata_command *ata_c = &xfer->c_ata_c;
2350 
2351 	ata_channel_lock(chp);
2352 
2353 	while ((ata_c->flags & AT_DONE) == 0)
2354 		cv_wait(&chq->c_cmd_finish, &chp->ch_lock);
2355 
2356 	ata_channel_unlock(chp);
2357 
2358 	KASSERT((ata_c->flags & AT_DONE) != 0);
2359 }
2360