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ata.c revision 1.63
      1 /*      $NetBSD: ata.c,v 1.63 2004/11/14 15:25:11 soren 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  * 3. All advertising materials mentioning features or use of this software
     15  *    must display the following acknowledgement:
     16  *  This product includes software developed by Manuel Bouyer.
     17  * 4. The name of the author may not be used to endorse or promote products
     18  *    derived from this software without specific prior written permission.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 __KERNEL_RCSID(0, "$NetBSD: ata.c,v 1.63 2004/11/14 15:25:11 soren Exp $");
     34 
     35 #ifndef ATADEBUG
     36 #define ATADEBUG
     37 #endif /* ATADEBUG */
     38 
     39 #include <sys/param.h>
     40 #include <sys/systm.h>
     41 #include <sys/kernel.h>
     42 #include <sys/malloc.h>
     43 #include <sys/device.h>
     44 #include <sys/conf.h>
     45 #include <sys/fcntl.h>
     46 #include <sys/proc.h>
     47 #include <sys/pool.h>
     48 #include <sys/kthread.h>
     49 #include <sys/errno.h>
     50 #include <sys/ataio.h>
     51 
     52 #include <machine/intr.h>
     53 #include <machine/bus.h>
     54 
     55 #include <dev/ata/atareg.h>
     56 #include <dev/ata/atavar.h>
     57 
     58 #include "locators.h"
     59 
     60 #include "atapibus.h"
     61 #include "ataraid.h"
     62 
     63 #if NATARAID > 0
     64 #include <dev/ata/ata_raidvar.h>
     65 #endif
     66 
     67 #define DEBUG_FUNCS  0x08
     68 #define DEBUG_PROBE  0x10
     69 #define DEBUG_DETACH 0x20
     70 #define	DEBUG_XFERS  0x40
     71 #ifdef ATADEBUG
     72 int atadebug_mask = 0;
     73 #define ATADEBUG_PRINT(args, level) \
     74         if (atadebug_mask & (level)) \
     75 		printf args
     76 #else
     77 #define ATADEBUG_PRINT(args, level)
     78 #endif
     79 
     80 POOL_INIT(ata_xfer_pool, sizeof(struct ata_xfer), 0, 0, 0, "ataspl", NULL);
     81 
     82 /*
     83  * A queue of atabus instances, used to ensure the same bus probe order
     84  * for a given hardware configuration at each boot.
     85  */
     86 struct atabus_initq_head atabus_initq_head =
     87     TAILQ_HEAD_INITIALIZER(atabus_initq_head);
     88 struct simplelock atabus_interlock = SIMPLELOCK_INITIALIZER;
     89 
     90 /*****************************************************************************
     91  * ATA bus layer.
     92  *
     93  * ATA controllers attach an atabus instance, which handles probing the bus
     94  * for drives, etc.
     95  *****************************************************************************/
     96 
     97 dev_type_open(atabusopen);
     98 dev_type_close(atabusclose);
     99 dev_type_ioctl(atabusioctl);
    100 
    101 const struct cdevsw atabus_cdevsw = {
    102 	atabusopen, atabusclose, noread, nowrite, atabusioctl,
    103 	nostop, notty, nopoll, nommap, nokqfilter,
    104 };
    105 
    106 extern struct cfdriver atabus_cd;
    107 
    108 
    109 /*
    110  * atabusprint:
    111  *
    112  *	Autoconfiguration print routine used by ATA controllers when
    113  *	attaching an atabus instance.
    114  */
    115 int
    116 atabusprint(void *aux, const char *pnp)
    117 {
    118 	struct ata_channel *chan = aux;
    119 
    120 	if (pnp)
    121 		aprint_normal("atabus at %s", pnp);
    122 	aprint_normal(" channel %d", chan->ch_channel);
    123 
    124 	return (UNCONF);
    125 }
    126 
    127 /*
    128  * ataprint:
    129  *
    130  *	Autoconfiguration print routine.
    131  */
    132 int
    133 ataprint(void *aux, const char *pnp)
    134 {
    135 	struct ata_device *adev = aux;
    136 
    137 	if (pnp)
    138 		aprint_normal("wd at %s", pnp);
    139 	aprint_normal(" drive %d", adev->adev_drv_data->drive);
    140 
    141 	return (UNCONF);
    142 }
    143 
    144 /*
    145  * ata_channel_attach:
    146  *
    147  *	Common parts of attaching an atabus to an ATA controller channel.
    148  */
    149 void
    150 ata_channel_attach(struct ata_channel *chp)
    151 {
    152 
    153 	if (chp->ch_flags & ATACH_DISABLED)
    154 		return;
    155 
    156 	callout_init(&chp->ch_callout);
    157 
    158 	TAILQ_INIT(&chp->ch_queue->queue_xfer);
    159 	chp->ch_queue->queue_freeze = 0;
    160 	chp->ch_queue->active_xfer = NULL;
    161 
    162 	chp->atabus = config_found(&chp->ch_atac->atac_dev, chp, atabusprint);
    163 }
    164 
    165 static void
    166 atabusconfig(struct atabus_softc *atabus_sc)
    167 {
    168 	struct ata_channel *chp = atabus_sc->sc_chan;
    169 	struct atac_softc *atac = chp->ch_atac;
    170 	int i, s;
    171 	struct atabus_initq *atabus_initq = NULL;
    172 
    173 	/* Probe for the drives. */
    174 	(*atac->atac_probe)(chp);
    175 
    176 	ATADEBUG_PRINT(("atabusattach: ch_drive_flags 0x%x 0x%x\n",
    177 	    chp->ch_drive[0].drive_flags, chp->ch_drive[1].drive_flags),
    178 	    DEBUG_PROBE);
    179 
    180 	/* If no drives, abort here */
    181 	for (i = 0; i < chp->ch_ndrive; i++)
    182 		if ((chp->ch_drive[i].drive_flags & DRIVE) != 0)
    183 			break;
    184 	if (i == chp->ch_ndrive)
    185 		goto out;
    186 
    187 	/* Shortcut in case we've been shutdown */
    188 	if (chp->ch_flags & ATACH_SHUTDOWN)
    189 		goto out;
    190 
    191 	/* Make sure the devices probe in atabus order to avoid jitter. */
    192 	simple_lock(&atabus_interlock);
    193 	while(1) {
    194 		atabus_initq = TAILQ_FIRST(&atabus_initq_head);
    195 		if (atabus_initq->atabus_sc == atabus_sc)
    196 			break;
    197 		ltsleep(&atabus_initq_head, PRIBIO, "ata_initq", 0,
    198 		    &atabus_interlock);
    199 	}
    200 	simple_unlock(&atabus_interlock);
    201 
    202 	/*
    203 	 * Attach an ATAPI bus, if needed.
    204 	 */
    205 	for (i = 0; i < chp->ch_ndrive; i++) {
    206 		if (chp->ch_drive[i].drive_flags & DRIVE_ATAPI) {
    207 #if NATAPIBUS > 0
    208 			(*atac->atac_atapibus_attach)(atabus_sc);
    209 #else
    210 			/*
    211 			 * Fake the autoconfig "not configured" message
    212 			 */
    213 			aprint_normal("atapibus at %s not configured\n",
    214 			    atac->atac_dev.dv_xname);
    215 			chp->atapibus = NULL;
    216 			s = splbio();
    217 			for (i = 0; i < chp->ch_ndrive; i++)
    218 				chp->ch_drive[i].drive_flags &= ~DRIVE_ATAPI;
    219 			splx(s);
    220 #endif
    221 			break;
    222 		}
    223 	}
    224 
    225 	for (i = 0; i < chp->ch_ndrive; i++) {
    226 		struct ata_device adev;
    227 		if ((chp->ch_drive[i].drive_flags &
    228 		    (DRIVE_ATA | DRIVE_OLD)) == 0) {
    229 			continue;
    230 		}
    231 		memset(&adev, 0, sizeof(struct ata_device));
    232 		adev.adev_bustype = atac->atac_bustype_ata;
    233 		adev.adev_channel = chp->ch_channel;
    234 		adev.adev_openings = 1;
    235 		adev.adev_drv_data = &chp->ch_drive[i];
    236 		chp->ata_drives[i] = config_found(&atabus_sc->sc_dev,
    237 		    &adev, ataprint);
    238 		if (chp->ata_drives[i] != NULL)
    239 			ata_probe_caps(&chp->ch_drive[i]);
    240 		else {
    241 			s = splbio();
    242 			chp->ch_drive[i].drive_flags &=
    243 			    ~(DRIVE_ATA | DRIVE_OLD);
    244 			splx(s);
    245 		}
    246 	}
    247 
    248 	/* now that we know the drives, the controller can set its modes */
    249 	if (atac->atac_set_modes) {
    250 		(*atac->atac_set_modes)(chp);
    251 		ata_print_modes(chp);
    252 	}
    253 #if NATARAID > 0
    254 	if (atac->atac_cap & ATAC_CAP_RAID)
    255 		for (i = 0; i < chp->ch_ndrive; i++)
    256 			if (chp->ata_drives[i] != NULL)
    257 				ata_raid_check_component(chp->ata_drives[i]);
    258 #endif /* NATARAID > 0 */
    259 
    260 	/*
    261 	 * reset drive_flags for unattached devices, reset state for attached
    262 	 * ones
    263 	 */
    264 	s = splbio();
    265 	for (i = 0; i < chp->ch_ndrive; i++) {
    266 		if (chp->ch_drive[i].drv_softc == NULL)
    267 			chp->ch_drive[i].drive_flags = 0;
    268 		else
    269 			chp->ch_drive[i].state = 0;
    270 	}
    271 	splx(s);
    272 
    273  out:
    274 	if (atabus_initq == NULL) {
    275 		simple_lock(&atabus_interlock);
    276 		while(1) {
    277 			atabus_initq = TAILQ_FIRST(&atabus_initq_head);
    278 			if (atabus_initq->atabus_sc == atabus_sc)
    279 				break;
    280 			ltsleep(&atabus_initq_head, PRIBIO, "ata_initq", 0,
    281 			    &atabus_interlock);
    282 		}
    283 		simple_unlock(&atabus_interlock);
    284 	}
    285         simple_lock(&atabus_interlock);
    286         TAILQ_REMOVE(&atabus_initq_head, atabus_initq, atabus_initq);
    287         simple_unlock(&atabus_interlock);
    288 
    289         free(atabus_initq, M_DEVBUF);
    290         wakeup(&atabus_initq_head);
    291 
    292 	ata_delref(chp);
    293 
    294 	config_pending_decr();
    295 }
    296 
    297 /*
    298  * atabus_thread:
    299  *
    300  *	Worker thread for the ATA bus.
    301  */
    302 static void
    303 atabus_thread(void *arg)
    304 {
    305 	struct atabus_softc *sc = arg;
    306 	struct ata_channel *chp = sc->sc_chan;
    307 	struct ata_xfer *xfer;
    308 	int i, s;
    309 
    310 	s = splbio();
    311 	chp->ch_flags |= ATACH_TH_RUN;
    312 
    313 	/*
    314 	 * Probe the drives.  Reset all flags to 0 to indicate to controllers
    315 	 * that can re-probe that all drives must be probed..
    316 	 *
    317 	 * Note: ch_ndrive may be changed during the probe.
    318 	 */
    319 	for (i = 0; i < ATA_MAXDRIVES; i++)
    320 		chp->ch_drive[i].drive_flags = 0;
    321 	splx(s);
    322 
    323 	/* Configure the devices on the bus. */
    324 	atabusconfig(sc);
    325 
    326 	for (;;) {
    327 		s = splbio();
    328 		if ((chp->ch_flags & (ATACH_TH_RESET | ATACH_SHUTDOWN)) == 0 &&
    329 		    (chp->ch_queue->active_xfer == NULL ||
    330 		     chp->ch_queue->queue_freeze == 0)) {
    331 			chp->ch_flags &= ~ATACH_TH_RUN;
    332 			(void) tsleep(&chp->ch_thread, PRIBIO, "atath", 0);
    333 			chp->ch_flags |= ATACH_TH_RUN;
    334 		}
    335 		if (chp->ch_flags & ATACH_SHUTDOWN) {
    336 			splx(s);
    337 			break;
    338 		}
    339 		if (chp->ch_flags & ATACH_TH_RESET) {
    340 			/*
    341 			 * ata_reset_channel() will freeze 2 times, so
    342 			 * unfreeze one time. Not a problem as we're at splbio
    343 			 */
    344 			chp->ch_queue->queue_freeze--;
    345 			ata_reset_channel(chp, AT_WAIT | chp->ch_reset_flags);
    346 		} else if (chp->ch_queue->active_xfer != NULL &&
    347 			   chp->ch_queue->queue_freeze == 1) {
    348 			/*
    349 			 * Caller has bumped queue_freeze, decrease it.
    350 			 */
    351 			chp->ch_queue->queue_freeze--;
    352 			xfer = chp->ch_queue->active_xfer;
    353 			KASSERT(xfer != NULL);
    354 			(*xfer->c_start)(xfer->c_chp, xfer);
    355 		} else if (chp->ch_queue->queue_freeze > 1)
    356 			panic("ata_thread: queue_freeze");
    357 		splx(s);
    358 	}
    359 	chp->ch_thread = NULL;
    360 	wakeup((void *)&chp->ch_flags);
    361 	kthread_exit(0);
    362 }
    363 
    364 /*
    365  * atabus_create_thread:
    366  *
    367  *	Helper routine to create the ATA bus worker thread.
    368  */
    369 static void
    370 atabus_create_thread(void *arg)
    371 {
    372 	struct atabus_softc *sc = arg;
    373 	struct ata_channel *chp = sc->sc_chan;
    374 	int error;
    375 
    376 	if ((error = kthread_create1(atabus_thread, sc, &chp->ch_thread,
    377 				     "%s", sc->sc_dev.dv_xname)) != 0)
    378 		aprint_error("%s: unable to create kernel thread: error %d\n",
    379 		    sc->sc_dev.dv_xname, error);
    380 }
    381 
    382 /*
    383  * atabus_match:
    384  *
    385  *	Autoconfiguration match routine.
    386  */
    387 static int
    388 atabus_match(struct device *parent, struct cfdata *cf, void *aux)
    389 {
    390 	struct ata_channel *chp = aux;
    391 
    392 	if (chp == NULL)
    393 		return (0);
    394 
    395 	if (cf->cf_loc[ATACF_CHANNEL] != chp->ch_channel &&
    396 	    cf->cf_loc[ATACF_CHANNEL] != ATACF_CHANNEL_DEFAULT)
    397 	    	return (0);
    398 
    399 	return (1);
    400 }
    401 
    402 /*
    403  * atabus_attach:
    404  *
    405  *	Autoconfiguration attach routine.
    406  */
    407 static void
    408 atabus_attach(struct device *parent, struct device *self, void *aux)
    409 {
    410 	struct atabus_softc *sc = (void *) self;
    411 	struct ata_channel *chp = aux;
    412 	struct atabus_initq *initq;
    413 
    414 	sc->sc_chan = chp;
    415 
    416 	aprint_normal("\n");
    417 	aprint_naive("\n");
    418 
    419         if (ata_addref(chp))
    420                 return;
    421 
    422 	initq = malloc(sizeof(*initq), M_DEVBUF, M_WAITOK);
    423 	initq->atabus_sc = sc;
    424 	TAILQ_INSERT_TAIL(&atabus_initq_head, initq, atabus_initq);
    425 	config_pending_incr();
    426 	kthread_create(atabus_create_thread, sc);
    427 }
    428 
    429 /*
    430  * atabus_activate:
    431  *
    432  *	Autoconfiguration activation routine.
    433  */
    434 static int
    435 atabus_activate(struct device *self, enum devact act)
    436 {
    437 	struct atabus_softc *sc = (void *) self;
    438 	struct ata_channel *chp = sc->sc_chan;
    439 	struct device *dev = NULL;
    440 	int s, i, error = 0;
    441 
    442 	s = splbio();
    443 	switch (act) {
    444 	case DVACT_ACTIVATE:
    445 		error = EOPNOTSUPP;
    446 		break;
    447 
    448 	case DVACT_DEACTIVATE:
    449 		/*
    450 		 * We might deactivate the children of atapibus twice
    451 		 * (once bia atapibus, once directly), but since the
    452 		 * generic autoconfiguration code maintains the DVF_ACTIVE
    453 		 * flag, it's safe.
    454 		 */
    455 		if ((dev = chp->atapibus) != NULL) {
    456 			error = config_deactivate(dev);
    457 			if (error)
    458 				goto out;
    459 		}
    460 
    461 		for (i = 0; i < chp->ch_ndrive; i++) {
    462 			if ((dev = chp->ch_drive[i].drv_softc) != NULL) {
    463 				ATADEBUG_PRINT(("atabus_activate: %s: "
    464 				    "deactivating %s\n", sc->sc_dev.dv_xname,
    465 				    dev->dv_xname),
    466 				    DEBUG_DETACH);
    467 				error = config_deactivate(dev);
    468 				if (error)
    469 					goto out;
    470 			}
    471 		}
    472 		break;
    473 	}
    474  out:
    475 	splx(s);
    476 
    477 #ifdef ATADEBUG
    478 	if (dev != NULL && error != 0)
    479 		ATADEBUG_PRINT(("atabus_activate: %s: "
    480 		    "error %d deactivating %s\n", sc->sc_dev.dv_xname,
    481 		    error, dev->dv_xname), DEBUG_DETACH);
    482 #endif /* ATADEBUG */
    483 
    484 	return (error);
    485 }
    486 
    487 /*
    488  * atabus_detach:
    489  *
    490  *	Autoconfiguration detach routine.
    491  */
    492 static int
    493 atabus_detach(struct device *self, int flags)
    494 {
    495 	struct atabus_softc *sc = (void *) self;
    496 	struct ata_channel *chp = sc->sc_chan;
    497 	struct device *dev = NULL;
    498 	int s, i, error = 0;
    499 
    500 	/* Shutdown the channel. */
    501 	s = splbio();		/* XXX ALSO NEED AN INTERLOCK HERE. */
    502 	chp->ch_flags |= ATACH_SHUTDOWN;
    503 	splx(s);
    504 	wakeup(&chp->ch_thread);
    505 	while (chp->ch_thread != NULL)
    506 		(void) tsleep((void *)&chp->ch_flags, PRIBIO, "atadown", 0);
    507 
    508 	/*
    509 	 * Detach atapibus and its children.
    510 	 */
    511 	if ((dev = chp->atapibus) != NULL) {
    512 		ATADEBUG_PRINT(("atabus_detach: %s: detaching %s\n",
    513 		    sc->sc_dev.dv_xname, dev->dv_xname), DEBUG_DETACH);
    514 		error = config_detach(dev, flags);
    515 		if (error)
    516 			goto out;
    517 	}
    518 
    519 	/*
    520 	 * Detach our other children.
    521 	 */
    522 	for (i = 0; i < chp->ch_ndrive; i++) {
    523 		if (chp->ch_drive[i].drive_flags & DRIVE_ATAPI)
    524 			continue;
    525 		if ((dev = chp->ch_drive[i].drv_softc) != NULL) {
    526 			ATADEBUG_PRINT(("atabus_detach: %s: detaching %s\n",
    527 			    sc->sc_dev.dv_xname, dev->dv_xname),
    528 			    DEBUG_DETACH);
    529 			error = config_detach(dev, flags);
    530 			if (error)
    531 				goto out;
    532 		}
    533 	}
    534 
    535  out:
    536 #ifdef ATADEBUG
    537 	if (dev != NULL && error != 0)
    538 		ATADEBUG_PRINT(("atabus_detach: %s: error %d detaching %s\n",
    539 		    sc->sc_dev.dv_xname, error, dev->dv_xname),
    540 		    DEBUG_DETACH);
    541 #endif /* ATADEBUG */
    542 
    543 	return (error);
    544 }
    545 
    546 CFATTACH_DECL(atabus, sizeof(struct atabus_softc),
    547     atabus_match, atabus_attach, atabus_detach, atabus_activate);
    548 
    549 /*****************************************************************************
    550  * Common ATA bus operations.
    551  *****************************************************************************/
    552 
    553 /* Get the disk's parameters */
    554 int
    555 ata_get_params(struct ata_drive_datas *drvp, u_int8_t flags,
    556     struct ataparams *prms)
    557 {
    558 	char tb[DEV_BSIZE];
    559 	struct ata_command ata_c;
    560 	struct ata_channel *chp = drvp->chnl_softc;
    561 	struct atac_softc *atac = chp->ch_atac;
    562 
    563 #if BYTE_ORDER == LITTLE_ENDIAN
    564 	int i;
    565 	u_int16_t *p;
    566 #endif
    567 
    568 	ATADEBUG_PRINT(("ata_get_parms\n"), DEBUG_FUNCS);
    569 
    570 	memset(tb, 0, DEV_BSIZE);
    571 	memset(prms, 0, sizeof(struct ataparams));
    572 	memset(&ata_c, 0, sizeof(struct ata_command));
    573 
    574 	if (drvp->drive_flags & DRIVE_ATA) {
    575 		ata_c.r_command = WDCC_IDENTIFY;
    576 		ata_c.r_st_bmask = WDCS_DRDY;
    577 		ata_c.r_st_pmask = 0;
    578 		ata_c.timeout = 3000; /* 3s */
    579 	} else if (drvp->drive_flags & DRIVE_ATAPI) {
    580 		ata_c.r_command = ATAPI_IDENTIFY_DEVICE;
    581 		ata_c.r_st_bmask = 0;
    582 		ata_c.r_st_pmask = 0;
    583 		ata_c.timeout = 10000; /* 10s */
    584 	} else {
    585 		ATADEBUG_PRINT(("ata_get_parms: no disks\n"),
    586 		    DEBUG_FUNCS|DEBUG_PROBE);
    587 		return CMD_ERR;
    588 	}
    589 	ata_c.flags = AT_READ | flags;
    590 	ata_c.data = tb;
    591 	ata_c.bcount = DEV_BSIZE;
    592 	if ((*atac->atac_bustype_ata->ata_exec_command)(drvp,
    593 						&ata_c) != ATACMD_COMPLETE) {
    594 		ATADEBUG_PRINT(("ata_get_parms: wdc_exec_command failed\n"),
    595 		    DEBUG_FUNCS|DEBUG_PROBE);
    596 		return CMD_AGAIN;
    597 	}
    598 	if (ata_c.flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
    599 		ATADEBUG_PRINT(("ata_get_parms: ata_c.flags=0x%x\n",
    600 		    ata_c.flags), DEBUG_FUNCS|DEBUG_PROBE);
    601 		return CMD_ERR;
    602 	} else {
    603 		/* if we didn't read any data something is wrong */
    604 		if ((ata_c.flags & AT_XFDONE) == 0)
    605 			return CMD_ERR;
    606 		/* Read in parameter block. */
    607 		memcpy(prms, tb, sizeof(struct ataparams));
    608 #if BYTE_ORDER == LITTLE_ENDIAN
    609 		/*
    610 		 * Shuffle string byte order.
    611 		 * ATAPI Mitsumi and NEC drives don't need this.
    612 		 */
    613 		if ((prms->atap_config & WDC_CFG_ATAPI_MASK) ==
    614 		    WDC_CFG_ATAPI &&
    615 		    ((prms->atap_model[0] == 'N' &&
    616 			prms->atap_model[1] == 'E') ||
    617 		     (prms->atap_model[0] == 'F' &&
    618 			 prms->atap_model[1] == 'X')))
    619 			return 0;
    620 		for (i = 0; i < sizeof(prms->atap_model); i += 2) {
    621 			p = (u_short *)(prms->atap_model + i);
    622 			*p = ntohs(*p);
    623 		}
    624 		for (i = 0; i < sizeof(prms->atap_serial); i += 2) {
    625 			p = (u_short *)(prms->atap_serial + i);
    626 			*p = ntohs(*p);
    627 		}
    628 		for (i = 0; i < sizeof(prms->atap_revision); i += 2) {
    629 			p = (u_short *)(prms->atap_revision + i);
    630 			*p = ntohs(*p);
    631 		}
    632 #endif
    633 		return CMD_OK;
    634 	}
    635 }
    636 
    637 int
    638 ata_set_mode(struct ata_drive_datas *drvp, u_int8_t mode, u_int8_t flags)
    639 {
    640 	struct ata_command ata_c;
    641 	struct ata_channel *chp = drvp->chnl_softc;
    642 	struct atac_softc *atac = chp->ch_atac;
    643 
    644 	ATADEBUG_PRINT(("ata_set_mode=0x%x\n", mode), DEBUG_FUNCS);
    645 	memset(&ata_c, 0, sizeof(struct ata_command));
    646 
    647 	ata_c.r_command = SET_FEATURES;
    648 	ata_c.r_st_bmask = 0;
    649 	ata_c.r_st_pmask = 0;
    650 	ata_c.r_features = WDSF_SET_MODE;
    651 	ata_c.r_count = mode;
    652 	ata_c.flags = flags;
    653 	ata_c.timeout = 1000; /* 1s */
    654 	if ((*atac->atac_bustype_ata->ata_exec_command)(drvp,
    655 						&ata_c) != ATACMD_COMPLETE)
    656 		return CMD_AGAIN;
    657 	if (ata_c.flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
    658 		return CMD_ERR;
    659 	}
    660 	return CMD_OK;
    661 }
    662 
    663 void
    664 ata_dmaerr(struct ata_drive_datas *drvp, int flags)
    665 {
    666 	/*
    667 	 * Downgrade decision: if we get NERRS_MAX in NXFER.
    668 	 * We start with n_dmaerrs set to NERRS_MAX-1 so that the
    669 	 * first error within the first NXFER ops will immediatly trigger
    670 	 * a downgrade.
    671 	 * If we got an error and n_xfers is bigger than NXFER reset counters.
    672 	 */
    673 	drvp->n_dmaerrs++;
    674 	if (drvp->n_dmaerrs >= NERRS_MAX && drvp->n_xfers <= NXFER) {
    675 		ata_downgrade_mode(drvp, flags);
    676 		drvp->n_dmaerrs = NERRS_MAX-1;
    677 		drvp->n_xfers = 0;
    678 		return;
    679 	}
    680 	if (drvp->n_xfers > NXFER) {
    681 		drvp->n_dmaerrs = 1; /* just got an error */
    682 		drvp->n_xfers = 1; /* restart counting from this error */
    683 	}
    684 }
    685 
    686 /*
    687  * Add a command to the queue and start controller.
    688  *
    689  * MUST BE CALLED AT splbio()!
    690  */
    691 void
    692 ata_exec_xfer(struct ata_channel *chp, struct ata_xfer *xfer)
    693 {
    694 
    695 	ATADEBUG_PRINT(("ata_exec_xfer %p channel %d drive %d\n", xfer,
    696 	    chp->ch_channel, xfer->c_drive), DEBUG_XFERS);
    697 
    698 	/* complete xfer setup */
    699 	xfer->c_chp = chp;
    700 
    701 	/* insert at the end of command list */
    702 	TAILQ_INSERT_TAIL(&chp->ch_queue->queue_xfer, xfer, c_xferchain);
    703 	ATADEBUG_PRINT(("atastart from ata_exec_xfer, flags 0x%x\n",
    704 	    chp->ch_flags), DEBUG_XFERS);
    705 	/*
    706 	 * if polling and can sleep, wait for the xfer to be at head of queue
    707 	 */
    708 	if ((xfer->c_flags & (C_POLL | C_WAIT)) ==  (C_POLL | C_WAIT)) {
    709 		while (chp->ch_queue->active_xfer != NULL ||
    710 		    TAILQ_FIRST(&chp->ch_queue->queue_xfer) != xfer) {
    711 			xfer->c_flags |= C_WAITACT;
    712 			tsleep(xfer, PRIBIO, "ataact", 0);
    713 			xfer->c_flags &= ~C_WAITACT;
    714 			if (xfer->c_flags & C_FREE) {
    715 				ata_free_xfer(chp, xfer);
    716 				return;
    717 			}
    718 		}
    719 	}
    720 	atastart(chp);
    721 }
    722 
    723 /*
    724  * Start I/O on a controller, for the given channel.
    725  * The first xfer may be not for our channel if the channel queues
    726  * are shared.
    727  *
    728  * MUST BE CALLED AT splbio()!
    729  */
    730 void
    731 atastart(struct ata_channel *chp)
    732 {
    733 	struct atac_softc *atac = chp->ch_atac;
    734 	struct ata_xfer *xfer;
    735 
    736 #ifdef ATA_DEBUG
    737 	int spl1, spl2;
    738 
    739 	spl1 = splbio();
    740 	spl2 = splbio();
    741 	if (spl2 != spl1) {
    742 		printf("atastart: not at splbio()\n");
    743 		panic("atastart");
    744 	}
    745 	splx(spl2);
    746 	splx(spl1);
    747 #endif /* ATA_DEBUG */
    748 
    749 	/* is there a xfer ? */
    750 	if ((xfer = TAILQ_FIRST(&chp->ch_queue->queue_xfer)) == NULL)
    751 		return;
    752 
    753 	/* adjust chp, in case we have a shared queue */
    754 	chp = xfer->c_chp;
    755 
    756 	if (chp->ch_queue->active_xfer != NULL) {
    757 		return; /* channel aleady active */
    758 	}
    759 	if (__predict_false(chp->ch_queue->queue_freeze > 0)) {
    760 		return; /* queue froozen */
    761 	}
    762 	/*
    763 	 * if someone is waiting for the command to be active, wake it up
    764 	 * and let it process the command
    765 	 */
    766 	if (xfer->c_flags & C_WAITACT) {
    767 		ATADEBUG_PRINT(("atastart: xfer %p channel %d drive %d "
    768 		    "wait active\n", xfer, chp->ch_channel, xfer->c_drive),
    769 		    DEBUG_XFERS);
    770 		wakeup(xfer);
    771 		return;
    772 	}
    773 #ifdef DIAGNOSTIC
    774 	if ((chp->ch_flags & ATACH_IRQ_WAIT) != 0)
    775 		panic("atastart: channel waiting for irq");
    776 #endif
    777 	if (atac->atac_claim_hw)
    778 		if (!(*atac->atac_claim_hw)(chp, 0))
    779 			return;
    780 
    781 	ATADEBUG_PRINT(("atastart: xfer %p channel %d drive %d\n", xfer,
    782 	    chp->ch_channel, xfer->c_drive), DEBUG_XFERS);
    783 	if (chp->ch_drive[xfer->c_drive].drive_flags & DRIVE_RESET) {
    784 		chp->ch_drive[xfer->c_drive].drive_flags &= ~DRIVE_RESET;
    785 		chp->ch_drive[xfer->c_drive].state = 0;
    786 	}
    787 	chp->ch_queue->active_xfer = xfer;
    788 	TAILQ_REMOVE(&chp->ch_queue->queue_xfer, xfer, c_xferchain);
    789 
    790 	if (atac->atac_cap & ATAC_CAP_NOIRQ)
    791 		KASSERT(xfer->c_flags & C_POLL);
    792 
    793 	xfer->c_start(chp, xfer);
    794 }
    795 
    796 struct ata_xfer *
    797 ata_get_xfer(int flags)
    798 {
    799 	struct ata_xfer *xfer;
    800 	int s;
    801 
    802 	s = splbio();
    803 	xfer = pool_get(&ata_xfer_pool,
    804 	    ((flags & ATAXF_NOSLEEP) != 0 ? PR_NOWAIT : PR_WAITOK));
    805 	splx(s);
    806 	if (xfer != NULL) {
    807 		memset(xfer, 0, sizeof(struct ata_xfer));
    808 	}
    809 	return xfer;
    810 }
    811 
    812 void
    813 ata_free_xfer(struct ata_channel *chp, struct ata_xfer *xfer)
    814 {
    815 	struct atac_softc *atac = chp->ch_atac;
    816 	int s;
    817 
    818 	if (xfer->c_flags & C_WAITACT) {
    819 		/* Someone is waiting for this xfer, so we can't free now */
    820 		xfer->c_flags |= C_FREE;
    821 		wakeup(xfer);
    822 		return;
    823 	}
    824 
    825 	if (atac->atac_free_hw)
    826 		(*atac->atac_free_hw)(chp);
    827 	s = splbio();
    828 	pool_put(&ata_xfer_pool, xfer);
    829 	splx(s);
    830 }
    831 
    832 /*
    833  * Kill off all pending xfers for a ata_channel.
    834  *
    835  * Must be called at splbio().
    836  */
    837 void
    838 ata_kill_pending(struct ata_drive_datas *drvp)
    839 {
    840 	struct ata_channel *chp = drvp->chnl_softc;
    841 	struct ata_xfer *xfer, *next_xfer;
    842 	int s = splbio();
    843 
    844 	for (xfer = TAILQ_FIRST(&chp->ch_queue->queue_xfer);
    845 	    xfer != NULL; xfer = next_xfer) {
    846 		next_xfer = TAILQ_NEXT(xfer, c_xferchain);
    847 		if (xfer->c_chp != chp || xfer->c_drive != drvp->drive)
    848 			continue;
    849 		TAILQ_REMOVE(&chp->ch_queue->queue_xfer, xfer, c_xferchain);
    850 		(*xfer->c_kill_xfer)(chp, xfer, KILL_GONE);
    851 	}
    852 
    853 	while ((xfer = chp->ch_queue->active_xfer) != NULL) {
    854 		if (xfer->c_chp == chp && xfer->c_drive == drvp->drive) {
    855 			drvp->drive_flags |= DRIVE_WAITDRAIN;
    856 			(void) tsleep(&chp->ch_queue->active_xfer,
    857 			    PRIBIO, "atdrn", 0);
    858 		} else {
    859 			/* no more xfer for us */
    860 			break;
    861 		}
    862 	}
    863 	splx(s);
    864 }
    865 
    866 /*
    867  * ata_reset_channel:
    868  *
    869  *	Reset and ATA channel.
    870  *
    871  *	MUST BE CALLED AT splbio()!
    872  */
    873 void
    874 ata_reset_channel(struct ata_channel *chp, int flags)
    875 {
    876 	struct atac_softc *atac = chp->ch_atac;
    877 	int drive;
    878 
    879 #ifdef ATA_DEBUG
    880 	int spl1, spl2;
    881 
    882 	spl1 = splbio();
    883 	spl2 = splbio();
    884 	if (spl2 != spl1) {
    885 		printf("ata_reset_channel: not at splbio()\n");
    886 		panic("ata_reset_channel");
    887 	}
    888 	splx(spl2);
    889 	splx(spl1);
    890 #endif /* ATA_DEBUG */
    891 
    892 	chp->ch_queue->queue_freeze++;
    893 
    894 	/*
    895 	 * If we can poll or wait it's OK, otherwise wake up the
    896 	 * kernel thread to do it for us.
    897 	 */
    898 	if ((flags & (AT_POLL | AT_WAIT)) == 0) {
    899 		if (chp->ch_flags & ATACH_TH_RESET) {
    900 			/* No need to schedule a reset more than one time. */
    901 			chp->ch_queue->queue_freeze--;
    902 			return;
    903 		}
    904 		chp->ch_flags |= ATACH_TH_RESET;
    905 		chp->ch_reset_flags = flags & (AT_RST_EMERG | AT_RST_NOCMD);
    906 		wakeup(&chp->ch_thread);
    907 		return;
    908 	}
    909 
    910 	(*atac->atac_bustype_ata->ata_reset_channel)(chp, flags);
    911 
    912 	for (drive = 0; drive < chp->ch_ndrive; drive++)
    913 		chp->ch_drive[drive].state = 0;
    914 
    915 	chp->ch_flags &= ~ATACH_TH_RESET;
    916 	if ((flags & AT_RST_EMERG) == 0)  {
    917 		chp->ch_queue->queue_freeze--;
    918 		atastart(chp);
    919 	} else {
    920 		/* make sure that we can use polled commands */
    921 		TAILQ_INIT(&chp->ch_queue->queue_xfer);
    922 		chp->ch_queue->queue_freeze = 0;
    923 		chp->ch_queue->active_xfer = NULL;
    924 	}
    925 }
    926 
    927 int
    928 ata_addref(struct ata_channel *chp)
    929 {
    930 	struct atac_softc *atac = chp->ch_atac;
    931 	struct scsipi_adapter *adapt = &atac->atac_atapi_adapter._generic;
    932 	int s, error = 0;
    933 
    934 	s = splbio();
    935 	if (adapt->adapt_refcnt++ == 0 &&
    936 	    adapt->adapt_enable != NULL) {
    937 		error = (*adapt->adapt_enable)(&atac->atac_dev, 1);
    938 		if (error)
    939 			adapt->adapt_refcnt--;
    940 	}
    941 	splx(s);
    942 	return (error);
    943 }
    944 
    945 void
    946 ata_delref(struct ata_channel *chp)
    947 {
    948 	struct atac_softc *atac = chp->ch_atac;
    949 	struct scsipi_adapter *adapt = &atac->atac_atapi_adapter._generic;
    950 	int s;
    951 
    952 	s = splbio();
    953 	if (adapt->adapt_refcnt-- == 1 &&
    954 	    adapt->adapt_enable != NULL)
    955 		(void) (*adapt->adapt_enable)(&atac->atac_dev, 0);
    956 	splx(s);
    957 }
    958 
    959 void
    960 ata_print_modes(struct ata_channel *chp)
    961 {
    962 	struct atac_softc *atac = chp->ch_atac;
    963 	int drive;
    964 	struct ata_drive_datas *drvp;
    965 
    966 	for (drive = 0; drive < 2; drive++) {
    967 		drvp = &chp->ch_drive[drive];
    968 		if ((drvp->drive_flags & DRIVE) == 0)
    969 			continue;
    970 		aprint_normal("%s(%s:%d:%d): using PIO mode %d",
    971 			drvp->drv_softc->dv_xname,
    972 			atac->atac_dev.dv_xname,
    973 			chp->ch_channel, drive, drvp->PIO_mode);
    974 		if (drvp->drive_flags & DRIVE_DMA)
    975 			aprint_normal(", DMA mode %d", drvp->DMA_mode);
    976 		if (drvp->drive_flags & DRIVE_UDMA) {
    977 			aprint_normal(", Ultra-DMA mode %d", drvp->UDMA_mode);
    978 			if (drvp->UDMA_mode == 2)
    979 				aprint_normal(" (Ultra/33)");
    980 			else if (drvp->UDMA_mode == 4)
    981 				aprint_normal(" (Ultra/66)");
    982 			else if (drvp->UDMA_mode == 5)
    983 				aprint_normal(" (Ultra/100)");
    984 			else if (drvp->UDMA_mode == 6)
    985 				aprint_normal(" (Ultra/133)");
    986 		}
    987 		if (drvp->drive_flags & (DRIVE_DMA | DRIVE_UDMA))
    988 			aprint_normal(" (using DMA)");
    989 		aprint_normal("\n");
    990 	}
    991 }
    992 
    993 /*
    994  * downgrade the transfer mode of a drive after an error. return 1 if
    995  * downgrade was possible, 0 otherwise.
    996  *
    997  * MUST BE CALLED AT splbio()!
    998  */
    999 int
   1000 ata_downgrade_mode(struct ata_drive_datas *drvp, int flags)
   1001 {
   1002 	struct ata_channel *chp = drvp->chnl_softc;
   1003 	struct atac_softc *atac = chp->ch_atac;
   1004 	struct device *drv_dev = drvp->drv_softc;
   1005 	int cf_flags = drv_dev->dv_cfdata->cf_flags;
   1006 
   1007 	/* if drive or controller don't know its mode, we can't do much */
   1008 	if ((drvp->drive_flags & DRIVE_MODE) == 0 ||
   1009 	    (atac->atac_set_modes == NULL))
   1010 		return 0;
   1011 	/* current drive mode was set by a config flag, let it this way */
   1012 	if ((cf_flags & ATA_CONFIG_PIO_SET) ||
   1013 	    (cf_flags & ATA_CONFIG_DMA_SET) ||
   1014 	    (cf_flags & ATA_CONFIG_UDMA_SET))
   1015 		return 0;
   1016 
   1017 	/*
   1018 	 * If we were using Ultra-DMA mode, downgrade to the next lower mode.
   1019 	 */
   1020 	if ((drvp->drive_flags & DRIVE_UDMA) && drvp->UDMA_mode >= 2) {
   1021 		drvp->UDMA_mode--;
   1022 		printf("%s: transfer error, downgrading to Ultra-DMA mode %d\n",
   1023 		    drv_dev->dv_xname, drvp->UDMA_mode);
   1024 	}
   1025 
   1026 	/*
   1027 	 * If we were using ultra-DMA, don't downgrade to multiword DMA.
   1028 	 */
   1029 	else if (drvp->drive_flags & (DRIVE_DMA | DRIVE_UDMA)) {
   1030 		drvp->drive_flags &= ~(DRIVE_DMA | DRIVE_UDMA);
   1031 		drvp->PIO_mode = drvp->PIO_cap;
   1032 		printf("%s: transfer error, downgrading to PIO mode %d\n",
   1033 		    drv_dev->dv_xname, drvp->PIO_mode);
   1034 	} else /* already using PIO, can't downgrade */
   1035 		return 0;
   1036 
   1037 	(*atac->atac_set_modes)(chp);
   1038 	ata_print_modes(chp);
   1039 	/* reset the channel, which will shedule all drives for setup */
   1040 	ata_reset_channel(chp, flags | AT_RST_NOCMD);
   1041 	return 1;
   1042 }
   1043 
   1044 /*
   1045  * Probe drive's capabilities, for use by the controller later
   1046  * Assumes drvp points to an existing drive.
   1047  */
   1048 void
   1049 ata_probe_caps(struct ata_drive_datas *drvp)
   1050 {
   1051 	struct ataparams params, params2;
   1052 	struct ata_channel *chp = drvp->chnl_softc;
   1053 	struct atac_softc *atac = chp->ch_atac;
   1054 	struct device *drv_dev = drvp->drv_softc;
   1055 	int i, printed, s;
   1056 	char *sep = "";
   1057 	int cf_flags;
   1058 
   1059 	if (ata_get_params(drvp, AT_WAIT, &params) != CMD_OK) {
   1060 		/* IDENTIFY failed. Can't tell more about the device */
   1061 		return;
   1062 	}
   1063 	if ((atac->atac_cap & (ATAC_CAP_DATA16 | ATAC_CAP_DATA32)) ==
   1064 	    (ATAC_CAP_DATA16 | ATAC_CAP_DATA32)) {
   1065 		/*
   1066 		 * Controller claims 16 and 32 bit transfers.
   1067 		 * Re-do an IDENTIFY with 32-bit transfers,
   1068 		 * and compare results.
   1069 		 */
   1070 		s = splbio();
   1071 		drvp->drive_flags |= DRIVE_CAP32;
   1072 		splx(s);
   1073 		ata_get_params(drvp, AT_WAIT, &params2);
   1074 		if (memcmp(&params, &params2, sizeof(struct ataparams)) != 0) {
   1075 			/* Not good. fall back to 16bits */
   1076 			s = splbio();
   1077 			drvp->drive_flags &= ~DRIVE_CAP32;
   1078 			splx(s);
   1079 		} else {
   1080 			aprint_normal("%s: 32-bit data port\n",
   1081 			    drv_dev->dv_xname);
   1082 		}
   1083 	}
   1084 #if 0 /* Some ultra-DMA drives claims to only support ATA-3. sigh */
   1085 	if (params.atap_ata_major > 0x01 &&
   1086 	    params.atap_ata_major != 0xffff) {
   1087 		for (i = 14; i > 0; i--) {
   1088 			if (params.atap_ata_major & (1 << i)) {
   1089 				aprint_normal("%s: ATA version %d\n",
   1090 				    drv_dev->dv_xname, i);
   1091 				drvp->ata_vers = i;
   1092 				break;
   1093 			}
   1094 		}
   1095 	}
   1096 #endif
   1097 
   1098 	/* An ATAPI device is at last PIO mode 3 */
   1099 	if (drvp->drive_flags & DRIVE_ATAPI)
   1100 		drvp->PIO_mode = 3;
   1101 
   1102 	/*
   1103 	 * It's not in the specs, but it seems that some drive
   1104 	 * returns 0xffff in atap_extensions when this field is invalid
   1105 	 */
   1106 	if (params.atap_extensions != 0xffff &&
   1107 	    (params.atap_extensions & WDC_EXT_MODES)) {
   1108 		printed = 0;
   1109 		/*
   1110 		 * XXX some drives report something wrong here (they claim to
   1111 		 * support PIO mode 8 !). As mode is coded on 3 bits in
   1112 		 * SET FEATURE, limit it to 7 (so limit i to 4).
   1113 		 * If higher mode than 7 is found, abort.
   1114 		 */
   1115 		for (i = 7; i >= 0; i--) {
   1116 			if ((params.atap_piomode_supp & (1 << i)) == 0)
   1117 				continue;
   1118 			if (i > 4)
   1119 				return;
   1120 			/*
   1121 			 * See if mode is accepted.
   1122 			 * If the controller can't set its PIO mode,
   1123 			 * assume the defaults are good, so don't try
   1124 			 * to set it
   1125 			 */
   1126 			if (atac->atac_set_modes)
   1127 				/*
   1128 				 * It's OK to pool here, it's fast enouth
   1129 				 * to not bother waiting for interrupt
   1130 				 */
   1131 				if (ata_set_mode(drvp, 0x08 | (i + 3),
   1132 				   AT_WAIT) != CMD_OK)
   1133 					continue;
   1134 			if (!printed) {
   1135 				aprint_normal("%s: drive supports PIO mode %d",
   1136 				    drv_dev->dv_xname, i + 3);
   1137 				sep = ",";
   1138 				printed = 1;
   1139 			}
   1140 			/*
   1141 			 * If controller's driver can't set its PIO mode,
   1142 			 * get the highter one for the drive.
   1143 			 */
   1144 			if (atac->atac_set_modes == NULL ||
   1145 			    atac->atac_pio_cap >= i + 3) {
   1146 				drvp->PIO_mode = i + 3;
   1147 				drvp->PIO_cap = i + 3;
   1148 				break;
   1149 			}
   1150 		}
   1151 		if (!printed) {
   1152 			/*
   1153 			 * We didn't find a valid PIO mode.
   1154 			 * Assume the values returned for DMA are buggy too
   1155 			 */
   1156 			return;
   1157 		}
   1158 		s = splbio();
   1159 		drvp->drive_flags |= DRIVE_MODE;
   1160 		splx(s);
   1161 		printed = 0;
   1162 		for (i = 7; i >= 0; i--) {
   1163 			if ((params.atap_dmamode_supp & (1 << i)) == 0)
   1164 				continue;
   1165 			if ((atac->atac_cap & ATAC_CAP_DMA) &&
   1166 			    atac->atac_set_modes != NULL)
   1167 				if (ata_set_mode(drvp, 0x20 | i, AT_WAIT)
   1168 				    != CMD_OK)
   1169 					continue;
   1170 			if (!printed) {
   1171 				aprint_normal("%s DMA mode %d", sep, i);
   1172 				sep = ",";
   1173 				printed = 1;
   1174 			}
   1175 			if (atac->atac_cap & ATAC_CAP_DMA) {
   1176 				if (atac->atac_set_modes != NULL &&
   1177 				    atac->atac_dma_cap < i)
   1178 					continue;
   1179 				drvp->DMA_mode = i;
   1180 				drvp->DMA_cap = i;
   1181 				s = splbio();
   1182 				drvp->drive_flags |= DRIVE_DMA;
   1183 				splx(s);
   1184 			}
   1185 			break;
   1186 		}
   1187 		if (params.atap_extensions & WDC_EXT_UDMA_MODES) {
   1188 			printed = 0;
   1189 			for (i = 7; i >= 0; i--) {
   1190 				if ((params.atap_udmamode_supp & (1 << i))
   1191 				    == 0)
   1192 					continue;
   1193 				if (atac->atac_set_modes != NULL &&
   1194 				    (atac->atac_cap & ATAC_CAP_UDMA))
   1195 					if (ata_set_mode(drvp, 0x40 | i,
   1196 					    AT_WAIT) != CMD_OK)
   1197 						continue;
   1198 				if (!printed) {
   1199 					aprint_normal("%s Ultra-DMA mode %d",
   1200 					    sep, i);
   1201 					if (i == 2)
   1202 						aprint_normal(" (Ultra/33)");
   1203 					else if (i == 4)
   1204 						aprint_normal(" (Ultra/66)");
   1205 					else if (i == 5)
   1206 						aprint_normal(" (Ultra/100)");
   1207 					else if (i == 6)
   1208 						aprint_normal(" (Ultra/133)");
   1209 					sep = ",";
   1210 					printed = 1;
   1211 				}
   1212 				if (atac->atac_cap & ATAC_CAP_UDMA) {
   1213 					if (atac->atac_set_modes != NULL &&
   1214 					    atac->atac_udma_cap < i)
   1215 						continue;
   1216 					drvp->UDMA_mode = i;
   1217 					drvp->UDMA_cap = i;
   1218 					s = splbio();
   1219 					drvp->drive_flags |= DRIVE_UDMA;
   1220 					splx(s);
   1221 				}
   1222 				break;
   1223 			}
   1224 		}
   1225 		aprint_normal("\n");
   1226 	}
   1227 
   1228 	s = splbio();
   1229 	drvp->drive_flags &= ~DRIVE_NOSTREAM;
   1230 	if (drvp->drive_flags & DRIVE_ATAPI) {
   1231 		if (atac->atac_cap & ATAC_CAP_ATAPI_NOSTREAM)
   1232 			drvp->drive_flags |= DRIVE_NOSTREAM;
   1233 	} else {
   1234 		if (atac->atac_cap & ATAC_CAP_ATA_NOSTREAM)
   1235 			drvp->drive_flags |= DRIVE_NOSTREAM;
   1236 	}
   1237 	splx(s);
   1238 
   1239 	/* Try to guess ATA version here, if it didn't get reported */
   1240 	if (drvp->ata_vers == 0) {
   1241 		if (drvp->drive_flags & DRIVE_UDMA)
   1242 			drvp->ata_vers = 4; /* should be at last ATA-4 */
   1243 		else if (drvp->PIO_cap > 2)
   1244 			drvp->ata_vers = 2; /* should be at last ATA-2 */
   1245 	}
   1246 	cf_flags = drv_dev->dv_cfdata->cf_flags;
   1247 	if (cf_flags & ATA_CONFIG_PIO_SET) {
   1248 		s = splbio();
   1249 		drvp->PIO_mode =
   1250 		    (cf_flags & ATA_CONFIG_PIO_MODES) >> ATA_CONFIG_PIO_OFF;
   1251 		drvp->drive_flags |= DRIVE_MODE;
   1252 		splx(s);
   1253 	}
   1254 	if ((atac->atac_cap & ATAC_CAP_DMA) == 0) {
   1255 		/* don't care about DMA modes */
   1256 		return;
   1257 	}
   1258 	if (cf_flags & ATA_CONFIG_DMA_SET) {
   1259 		s = splbio();
   1260 		if ((cf_flags & ATA_CONFIG_DMA_MODES) ==
   1261 		    ATA_CONFIG_DMA_DISABLE) {
   1262 			drvp->drive_flags &= ~DRIVE_DMA;
   1263 		} else {
   1264 			drvp->DMA_mode = (cf_flags & ATA_CONFIG_DMA_MODES) >>
   1265 			    ATA_CONFIG_DMA_OFF;
   1266 			drvp->drive_flags |= DRIVE_DMA | DRIVE_MODE;
   1267 		}
   1268 		splx(s);
   1269 	}
   1270 	if ((atac->atac_cap & ATAC_CAP_UDMA) == 0) {
   1271 		/* don't care about UDMA modes */
   1272 		return;
   1273 	}
   1274 	if (cf_flags & ATA_CONFIG_UDMA_SET) {
   1275 		s = splbio();
   1276 		if ((cf_flags & ATA_CONFIG_UDMA_MODES) ==
   1277 		    ATA_CONFIG_UDMA_DISABLE) {
   1278 			drvp->drive_flags &= ~DRIVE_UDMA;
   1279 		} else {
   1280 			drvp->UDMA_mode = (cf_flags & ATA_CONFIG_UDMA_MODES) >>
   1281 			    ATA_CONFIG_UDMA_OFF;
   1282 			drvp->drive_flags |= DRIVE_UDMA | DRIVE_MODE;
   1283 		}
   1284 		splx(s);
   1285 	}
   1286 }
   1287 
   1288 /* management of the /dev/atabus* devices */
   1289 int
   1290 atabusopen(dev_t dev, int flag, int fmt, struct proc *p)
   1291 {
   1292         struct atabus_softc *sc;
   1293         int error, unit = minor(dev);
   1294 
   1295         if (unit >= atabus_cd.cd_ndevs ||
   1296             (sc = atabus_cd.cd_devs[unit]) == NULL)
   1297                 return (ENXIO);
   1298 
   1299         if (sc->sc_flags & ATABUSCF_OPEN)
   1300                 return (EBUSY);
   1301 
   1302         if ((error = ata_addref(sc->sc_chan)) != 0)
   1303                 return (error);
   1304 
   1305         sc->sc_flags |= ATABUSCF_OPEN;
   1306 
   1307         return (0);
   1308 }
   1309 
   1310 
   1311 int
   1312 atabusclose(dev_t dev, int flag, int fmt, struct proc *p)
   1313 {
   1314         struct atabus_softc *sc = atabus_cd.cd_devs[minor(dev)];
   1315 
   1316         ata_delref(sc->sc_chan);
   1317 
   1318         sc->sc_flags &= ~ATABUSCF_OPEN;
   1319 
   1320         return (0);
   1321 }
   1322 
   1323 int
   1324 atabusioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
   1325 {
   1326         struct atabus_softc *sc = atabus_cd.cd_devs[minor(dev)];
   1327 	struct ata_channel *chp = sc->sc_chan;
   1328 	int min_drive, max_drive, drive;
   1329         int error;
   1330 	int s;
   1331 
   1332         /*
   1333          * Enforce write permission for ioctls that change the
   1334          * state of the bus.  Host adapter specific ioctls must
   1335          * be checked by the adapter driver.
   1336          */
   1337         switch (cmd) {
   1338         case ATABUSIOSCAN:
   1339         case ATABUSIODETACH:
   1340         case ATABUSIORESET:
   1341                 if ((flag & FWRITE) == 0)
   1342                         return (EBADF);
   1343         }
   1344 
   1345         switch (cmd) {
   1346         case ATABUSIORESET:
   1347 		s = splbio();
   1348 		ata_reset_channel(sc->sc_chan, AT_WAIT | AT_POLL);
   1349 		splx(s);
   1350 		error = 0;
   1351 		break;
   1352 	case ATABUSIOSCAN:
   1353 	{
   1354 #if 0
   1355 		struct atabusioscan_args *a=
   1356 		    (struct atabusioscan_args *)addr;
   1357 #endif
   1358 		if ((chp->ch_drive[0].drive_flags & DRIVE_OLD) ||
   1359 		    (chp->ch_drive[1].drive_flags & DRIVE_OLD))
   1360 			return (EOPNOTSUPP);
   1361 		return (EOPNOTSUPP);
   1362 	}
   1363 	case ATABUSIODETACH:
   1364 	{
   1365 		struct atabusioscan_args *a=
   1366 		    (struct atabusioscan_args *)addr;
   1367 		if ((chp->ch_drive[0].drive_flags & DRIVE_OLD) ||
   1368 		    (chp->ch_drive[1].drive_flags & DRIVE_OLD))
   1369 			return (EOPNOTSUPP);
   1370 		switch (a->at_dev) {
   1371 		case -1:
   1372 			min_drive = 0;
   1373 			max_drive = 1;
   1374 			break;
   1375 		case 0:
   1376 		case 1:
   1377 			min_drive = max_drive = a->at_dev;
   1378 			break;
   1379 		default:
   1380 			return (EINVAL);
   1381 		}
   1382 		for (drive = min_drive; drive <= max_drive; drive++) {
   1383 			if (chp->ch_drive[drive].drv_softc != NULL) {
   1384 				error = config_detach(
   1385 				    chp->ch_drive[drive].drv_softc, 0);
   1386 				if (error)
   1387 					return (error);
   1388 				chp->ch_drive[drive].drv_softc = NULL;
   1389 			}
   1390 		}
   1391 		error = 0;
   1392 		break;
   1393 	}
   1394 	default:
   1395 		error = ENOTTY;
   1396 	}
   1397 	return (error);
   1398 };
   1399