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ata.c revision 1.150
      1 /*	$NetBSD: ata.c,v 1.150 2019/08/21 04:51:41 msaitoh 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 1.150 2019/08/21 04:51:41 msaitoh 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 controller.
   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