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      1 /*	$NetBSD: atapi_wdc.c,v 1.141 2021/10/05 08:01:05 rin Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1998, 2001 Manuel Bouyer.
      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: atapi_wdc.c,v 1.141 2021/10/05 08:01:05 rin Exp $");
     29 
     30 #ifndef ATADEBUG
     31 #define ATADEBUG
     32 #endif /* ATADEBUG */
     33 
     34 #include <sys/param.h>
     35 #include <sys/systm.h>
     36 #include <sys/kernel.h>
     37 #include <sys/file.h>
     38 #include <sys/stat.h>
     39 #include <sys/buf.h>
     40 #include <sys/malloc.h>
     41 #include <sys/device.h>
     42 #include <sys/syslog.h>
     43 #include <sys/proc.h>
     44 #include <sys/dvdio.h>
     45 
     46 #include <sys/intr.h>
     47 #include <sys/bus.h>
     48 
     49 #ifndef __BUS_SPACE_HAS_STREAM_METHODS
     50 #define	bus_space_write_multi_stream_2	bus_space_write_multi_2
     51 #define	bus_space_write_multi_stream_4	bus_space_write_multi_4
     52 #define	bus_space_read_multi_stream_2	bus_space_read_multi_2
     53 #define	bus_space_read_multi_stream_4	bus_space_read_multi_4
     54 #endif /* __BUS_SPACE_HAS_STREAM_METHODS */
     55 
     56 #include <dev/ata/ataconf.h>
     57 #include <dev/ata/atareg.h>
     58 #include <dev/ata/atavar.h>
     59 #include <dev/ic/wdcreg.h>
     60 #include <dev/ic/wdcvar.h>
     61 
     62 #include <dev/scsipi/scsi_all.h> /* for SCSI status */
     63 
     64 #define DEBUG_INTR   0x01
     65 #define DEBUG_XFERS  0x02
     66 #define DEBUG_STATUS 0x04
     67 #define DEBUG_FUNCS  0x08
     68 #define DEBUG_PROBE  0x10
     69 #ifdef ATADEBUG
     70 #ifndef ATADEBUG_ATAPI_MASK
     71 #define ATADEBUG_ATAPI_MASK 0x0
     72 #endif
     73 int wdcdebug_atapi_mask = ATADEBUG_ATAPI_MASK;
     74 #define ATADEBUG_PRINT(args, level) \
     75 	if (wdcdebug_atapi_mask & (level)) \
     76 		printf args
     77 #else
     78 #define ATADEBUG_PRINT(args, level)
     79 #endif
     80 
     81 #define ATAPI_DELAY 10	/* 10 ms, this is used only before sending a cmd */
     82 #define ATAPI_MODE_DELAY 1000	/* 1s, timeout for SET_FEATYRE cmds */
     83 
     84 static int	wdc_atapi_get_params(struct scsipi_channel *, int,
     85 				     struct ataparams *);
     86 static void	wdc_atapi_probe_device(struct atapibus_softc *, int);
     87 static void	wdc_atapi_minphys (struct buf *bp);
     88 static int	wdc_atapi_start(struct ata_channel *,struct ata_xfer *);
     89 static int	wdc_atapi_intr(struct ata_channel *, struct ata_xfer *, int);
     90 static void	wdc_atapi_kill_xfer(struct ata_channel *,
     91 				    struct ata_xfer *, int);
     92 static void	wdc_atapi_phase_complete(struct ata_xfer *, int);
     93 static int	wdc_atapi_poll(struct ata_channel *, struct ata_xfer *);
     94 static void	wdc_atapi_done(struct ata_channel *, struct ata_xfer *);
     95 static void	wdc_atapi_reset(struct ata_channel *, struct ata_xfer *);
     96 static void	wdc_atapi_scsipi_request(struct scsipi_channel *,
     97 					 scsipi_adapter_req_t, void *);
     98 static void	wdc_atapi_kill_pending(struct scsipi_periph *);
     99 static void	wdc_atapi_polldsc(void *arg);
    100 
    101 #define MAX_SIZE MAXPHYS
    102 
    103 static const struct scsipi_bustype wdc_atapi_bustype = {
    104 	.bustype_type = SCSIPI_BUSTYPE_ATAPI,
    105 	.bustype_cmd = atapi_scsipi_cmd,
    106 	.bustype_interpret_sense = atapi_interpret_sense,
    107 	.bustype_printaddr = atapi_print_addr,
    108 	.bustype_kill_pending = wdc_atapi_kill_pending,
    109 	.bustype_async_event_xfer_mode = NULL,
    110 };
    111 
    112 void
    113 wdc_atapibus_attach(struct atabus_softc *ata_sc)
    114 {
    115 	struct ata_channel *chp = ata_sc->sc_chan;
    116 	struct atac_softc *atac = chp->ch_atac;
    117 	struct scsipi_adapter *adapt = &atac->atac_atapi_adapter._generic;
    118 	struct scsipi_channel *chan = &chp->ch_atapi_channel;
    119 
    120 	/*
    121 	 * Fill in the scsipi_adapter.
    122 	 */
    123 	adapt->adapt_dev = atac->atac_dev;
    124 	adapt->adapt_nchannels = atac->atac_nchannels;
    125 	adapt->adapt_request = wdc_atapi_scsipi_request;
    126 	adapt->adapt_minphys = wdc_atapi_minphys;
    127 	if (atac->atac_cap & ATAC_CAP_NOIRQ)
    128 		adapt->adapt_flags |= SCSIPI_ADAPT_POLL_ONLY;
    129 	atac->atac_atapi_adapter.atapi_probe_device = wdc_atapi_probe_device;
    130 
    131 	/*
    132 	 * Fill in the scsipi_channel.
    133 	 */
    134 	memset(chan, 0, sizeof(*chan));
    135 	chan->chan_adapter = adapt;
    136 	chan->chan_bustype = &wdc_atapi_bustype;
    137 	chan->chan_channel = chp->ch_channel;
    138 	chan->chan_flags = SCSIPI_CHAN_OPENINGS;
    139 	chan->chan_openings = 1;
    140 	chan->chan_max_periph = 1;
    141 	chan->chan_ntargets = chp->ch_ndrives;
    142 	chan->chan_nluns = 1;
    143 
    144 	chp->atapibus = config_found(ata_sc->sc_dev, chan, atapiprint,
    145 	    CFARGS(.iattr = "atapi"));
    146 }
    147 
    148 static void
    149 wdc_atapi_minphys(struct buf *bp)
    150 {
    151 
    152 	if (bp->b_bcount > MAX_SIZE)
    153 		bp->b_bcount = MAX_SIZE;
    154 	minphys(bp);
    155 }
    156 
    157 /*
    158  * Kill off all pending xfers for a periph.
    159  *
    160  * Must be called with adapter lock held
    161  */
    162 static void
    163 wdc_atapi_kill_pending(struct scsipi_periph *periph)
    164 {
    165 	struct atac_softc *atac =
    166 	    device_private(periph->periph_channel->chan_adapter->adapt_dev);
    167 	struct ata_channel *chp =
    168 	    atac->atac_channels[periph->periph_channel->chan_channel];
    169 
    170 	ata_kill_pending(&chp->ch_drive[periph->periph_target]);
    171 }
    172 
    173 static void
    174 wdc_atapi_kill_xfer(struct ata_channel *chp, struct ata_xfer *xfer, int reason)
    175 {
    176 	struct scsipi_xfer *sc_xfer = xfer->c_scsipi;
    177 	bool deactivate = true;
    178 
    179 	/* remove this command from xfer queue */
    180 	switch (reason) {
    181 	case KILL_GONE_INACTIVE:
    182 		deactivate = false;
    183 		/* FALLTHROUGH */
    184 	case KILL_GONE:
    185 		sc_xfer->error = XS_DRIVER_STUFFUP;
    186 		break;
    187 	case KILL_RESET:
    188 		sc_xfer->error = XS_RESET;
    189 		break;
    190 	default:
    191 		printf("wdc_ata_bio_kill_xfer: unknown reason %d\n",
    192 		    reason);
    193 		panic("wdc_ata_bio_kill_xfer");
    194 	}
    195 
    196 	if (deactivate)
    197 		ata_deactivate_xfer(chp, xfer);
    198 
    199 	ata_free_xfer(chp, xfer);
    200 	scsipi_done(sc_xfer);
    201 }
    202 
    203 static int
    204 wdc_atapi_get_params(struct scsipi_channel *chan, int drive,
    205     struct ataparams *id)
    206 {
    207 	struct wdc_softc *wdc = device_private(chan->chan_adapter->adapt_dev);
    208 	struct atac_softc *atac = &wdc->sc_atac;
    209 	struct wdc_regs *wdr = &wdc->regs[chan->chan_channel];
    210 	struct ata_channel *chp = atac->atac_channels[chan->chan_channel];
    211 	struct ata_xfer *xfer;
    212 	int rv;
    213 
    214 	xfer = ata_get_xfer(chp, false);
    215 	if (xfer == NULL) {
    216 		printf("wdc_atapi_get_params: no xfer\n");
    217 		return EBUSY;
    218 	}
    219 
    220 	xfer->c_ata_c.r_command = ATAPI_SOFT_RESET;
    221 	xfer->c_ata_c.r_st_bmask = 0;
    222 	xfer->c_ata_c.r_st_pmask = 0;
    223 	xfer->c_ata_c.flags = AT_WAIT | AT_POLL;
    224 	xfer->c_ata_c.timeout = WDC_RESET_WAIT;
    225 
    226 	wdc_exec_command(&chp->ch_drive[drive], xfer);
    227 	ata_wait_cmd(chp, xfer);
    228 
    229 	if (xfer->c_ata_c.flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
    230 		ATADEBUG_PRINT(("wdc_atapi_get_params: ATAPI_SOFT_RESET "
    231 		    "failed for drive %s:%d:%d: error 0x%x\n",
    232 		    device_xname(atac->atac_dev), chp->ch_channel, drive,
    233 		    xfer->c_ata_c.r_error), DEBUG_PROBE);
    234 		rv = -1;
    235 		goto out_xfer;
    236 	}
    237 	chp->ch_drive[drive].state = 0;
    238 
    239 	ata_free_xfer(chp, xfer);
    240 
    241 	(void)bus_space_read_1(wdr->cmd_iot, wdr->cmd_iohs[wd_status], 0);
    242 
    243 	/* Some ATAPI devices need a bit more time after software reset. */
    244 	delay(5000);
    245 	if (ata_get_params(&chp->ch_drive[drive], AT_WAIT, id) != 0) {
    246 		ATADEBUG_PRINT(("wdc_atapi_get_params: ATAPI_IDENTIFY_DEVICE "
    247 		    "failed for drive %s:%d:%d\n",
    248 		    device_xname(atac->atac_dev), chp->ch_channel, drive),
    249 		    DEBUG_PROBE);
    250 		rv = -1;
    251 		goto out;
    252 	}
    253 	rv = 0;
    254 out:
    255 	return rv;
    256 
    257 out_xfer:
    258 	ata_free_xfer(chp, xfer);
    259 	return rv;
    260 }
    261 
    262 static void
    263 wdc_atapi_probe_device(struct atapibus_softc *sc, int target)
    264 {
    265 	struct scsipi_channel *chan = sc->sc_channel;
    266 	struct scsipi_periph *periph;
    267 	struct ataparams ids;
    268 	struct ataparams *id = &ids;
    269 	struct wdc_softc *wdc = device_private(chan->chan_adapter->adapt_dev);
    270 	struct atac_softc *atac = &wdc->sc_atac;
    271 	struct ata_channel *chp = atac->atac_channels[chan->chan_channel];
    272 	struct ata_drive_datas *drvp = &chp->ch_drive[target];
    273 	struct scsipibus_attach_args sa;
    274 	char serial_number[21], model[41], firmware_revision[9];
    275 	int s;
    276 
    277 	/* skip if already attached */
    278 	if (scsipi_lookup_periph(chan, target, 0) != NULL)
    279 		return;
    280 
    281 	/* if no ATAPI device detected at wdc attach time, skip */
    282 	if (drvp->drive_type != ATA_DRIVET_ATAPI) {
    283 		ATADEBUG_PRINT(("wdc_atapi_probe_device: "
    284 		    "drive %d not present\n", target), DEBUG_PROBE);
    285 		return;
    286 	}
    287 
    288 	if (wdc_atapi_get_params(chan, target, id) == 0) {
    289 #ifdef ATAPI_DEBUG_PROBE
    290 		printf("%s drive %d: cmdsz 0x%x drqtype 0x%x\n",
    291 		    device_xname(sc->sc_dev), target,
    292 		    id->atap_config & ATAPI_CFG_CMD_MASK,
    293 		    id->atap_config & ATAPI_CFG_DRQ_MASK);
    294 #endif
    295 		periph = scsipi_alloc_periph(M_WAITOK);
    296 		periph->periph_dev = NULL;
    297 		periph->periph_channel = chan;
    298 		periph->periph_switch = &atapi_probe_periphsw;
    299 		periph->periph_target = target;
    300 		periph->periph_lun = 0;
    301 		periph->periph_quirks = PQUIRK_ONLYBIG;
    302 
    303 #ifdef SCSIPI_DEBUG
    304 		if (SCSIPI_DEBUG_TYPE == SCSIPI_BUSTYPE_ATAPI &&
    305 		    SCSIPI_DEBUG_TARGET == target)
    306 			periph->periph_dbflags |= SCSIPI_DEBUG_FLAGS;
    307 #endif
    308 		periph->periph_type = ATAPI_CFG_TYPE(id->atap_config);
    309 		if (id->atap_config & ATAPI_CFG_REMOV)
    310 			periph->periph_flags |= PERIPH_REMOVABLE;
    311 		if (periph->periph_type == T_SEQUENTIAL) {
    312 			s = splbio();
    313 			drvp->drive_flags |= ATA_DRIVE_ATAPIDSCW;
    314 			splx(s);
    315 		}
    316 
    317 		sa.sa_periph = periph;
    318 		sa.sa_inqbuf.type =  ATAPI_CFG_TYPE(id->atap_config);
    319 		sa.sa_inqbuf.removable = id->atap_config & ATAPI_CFG_REMOV ?
    320 		    T_REMOV : T_FIXED;
    321 		strnvisx(model, sizeof(model), id->atap_model,
    322 		    sizeof(id->atap_model), VIS_TRIM|VIS_SAFE|VIS_OCTAL);
    323 		strnvisx(serial_number, sizeof(serial_number),
    324 		    id->atap_serial, sizeof(id->atap_serial),
    325 		    VIS_TRIM|VIS_SAFE|VIS_OCTAL);
    326 		strnvisx(firmware_revision, sizeof(firmware_revision),
    327 		    id->atap_revision, sizeof(id->atap_revision),
    328 		    VIS_TRIM|VIS_SAFE|VIS_OCTAL);
    329 		sa.sa_inqbuf.vendor = model;
    330 		sa.sa_inqbuf.product = serial_number;
    331 		sa.sa_inqbuf.revision = firmware_revision;
    332 
    333 		/*
    334 		 * Determine the operating mode capabilities of the device.
    335 		 */
    336 		if ((id->atap_config & ATAPI_CFG_CMD_MASK) == ATAPI_CFG_CMD_16)
    337 			periph->periph_cap |= PERIPH_CAP_CMD16;
    338 		/* XXX This is gross. */
    339 		periph->periph_cap |= (id->atap_config & ATAPI_CFG_DRQ_MASK);
    340 
    341 		drvp->drv_softc = atapi_probe_device(sc, target, periph, &sa);
    342 
    343 		if (drvp->drv_softc)
    344 			ata_probe_caps(drvp);
    345 		else {
    346 			s = splbio();
    347 			drvp->drive_type = ATA_DRIVET_NONE;
    348 			splx(s);
    349 		}
    350 	} else {
    351 		s = splbio();
    352 		drvp->drive_type = ATA_DRIVET_NONE;
    353 		splx(s);
    354 	}
    355 }
    356 
    357 static const struct ata_xfer_ops wdc_atapi_xfer_ops = {
    358 	.c_start = wdc_atapi_start,
    359 	.c_intr = wdc_atapi_intr,
    360 	.c_poll = wdc_atapi_poll,
    361 	.c_abort = wdc_atapi_reset,
    362 	.c_kill_xfer = wdc_atapi_kill_xfer,
    363 };
    364 
    365 static void
    366 wdc_atapi_scsipi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
    367     void *arg)
    368 {
    369 	struct scsipi_adapter *adapt = chan->chan_adapter;
    370 	struct scsipi_periph *periph;
    371 	struct scsipi_xfer *sc_xfer;
    372 	struct wdc_softc *wdc = device_private(adapt->adapt_dev);
    373 	struct atac_softc *atac = &wdc->sc_atac;
    374 	struct ata_xfer *xfer;
    375 	int channel = chan->chan_channel;
    376 	int drive, s;
    377 
    378 	switch (req) {
    379 	case ADAPTER_REQ_RUN_XFER:
    380 		sc_xfer = arg;
    381 		periph = sc_xfer->xs_periph;
    382 		drive = periph->periph_target;
    383 
    384 		ATADEBUG_PRINT(("wdc_atapi_scsipi_request %s:%d:%d\n",
    385 		    device_xname(atac->atac_dev), channel, drive),
    386 		    DEBUG_XFERS);
    387 		if (!device_is_active(atac->atac_dev)) {
    388 			sc_xfer->error = XS_DRIVER_STUFFUP;
    389 			scsipi_done(sc_xfer);
    390 			return;
    391 		}
    392 
    393 		xfer = ata_get_xfer(atac->atac_channels[channel], false);
    394 		if (xfer == NULL) {
    395 			sc_xfer->error = XS_RESOURCE_SHORTAGE;
    396 			scsipi_done(sc_xfer);
    397 			return;
    398 		}
    399 
    400 		if (sc_xfer->xs_control & XS_CTL_POLL)
    401 			xfer->c_flags |= C_POLL;
    402 #if NATA_DMA
    403 		if ((atac->atac_channels[channel]->ch_drive[drive].drive_flags &
    404 		    (ATA_DRIVE_DMA | ATA_DRIVE_UDMA)) && sc_xfer->datalen > 0)
    405 			xfer->c_flags |= C_DMA;
    406 #endif
    407 #if NATA_DMA && NATA_PIOBM
    408 		else
    409 #endif
    410 #if NATA_PIOBM
    411 		if ((atac->atac_cap & ATAC_CAP_PIOBM) &&
    412 		    sc_xfer->datalen > 0)
    413 			xfer->c_flags |= C_PIOBM;
    414 #endif
    415 		xfer->c_drive = drive;
    416 		xfer->c_flags |= C_ATAPI;
    417 #if NATA_DMA
    418 		if (sc_xfer->cmd->opcode == GPCMD_REPORT_KEY ||
    419 		    sc_xfer->cmd->opcode == GPCMD_SEND_KEY ||
    420 		    sc_xfer->cmd->opcode == GPCMD_READ_DVD_STRUCTURE) {
    421 			/*
    422 			 * DVD authentication commands must always be done in
    423 			 * PIO mode.
    424 			 */
    425 			xfer->c_flags &= ~C_DMA;
    426 		}
    427 
    428 		/*
    429 		 * DMA normally can't deal with transfers which are not a
    430 		 * multiple of its databus width. It's a bug to request odd
    431 		 * length transfers for ATAPI.
    432 		 *
    433 		 * Some devices also can't cope with unaligned DMA xfers
    434 		 * either. Also some devices seem to not handle DMA xfers of
    435 		 * less than 4 bytes.
    436 		 *
    437 		 * By enforcing at least 4 byte aligned offset and length for
    438 		 * DMA, we might use PIO where DMA could be allowed but better
    439 		 * safe than sorry as recent problems proved.
    440 		 *
    441 		 * Offending structures that are thus done by PIO instead of
    442 		 * DMA are normally small structures since all bulkdata is
    443 		 * aligned. But as the request may come from userland, we have
    444 		 * to protect against it anyway.
    445 		 *
    446 		 * XXX check for the 32 bit wide flag?
    447 		 */
    448 
    449 		if (((uintptr_t) sc_xfer->data) & 0x03)
    450 			xfer->c_flags &= ~C_DMA;
    451 		if ((sc_xfer->datalen < 4) || (sc_xfer->datalen & 0x03))
    452 			xfer->c_flags &= ~C_DMA;
    453 #endif	/* NATA_DMA */
    454 
    455 		xfer->c_databuf = sc_xfer->data;
    456 		xfer->c_bcount = sc_xfer->datalen;
    457 		xfer->ops = &wdc_atapi_xfer_ops;
    458 		xfer->c_scsipi = sc_xfer;
    459 		xfer->c_atapi.c_dscpoll = 0;
    460 		s = splbio();
    461 		ata_exec_xfer(atac->atac_channels[channel], xfer);
    462 #ifdef DIAGNOSTIC
    463 		if ((sc_xfer->xs_control & XS_CTL_POLL) != 0 &&
    464 		    (sc_xfer->xs_status & XS_STS_DONE) == 0)
    465 			panic("wdc_atapi_scsipi_request: polled command "
    466 			    "not done");
    467 #endif
    468 		splx(s);
    469 		return;
    470 
    471 	default:
    472 		/* Not supported, nothing to do. */
    473 		;
    474 	}
    475 }
    476 
    477 static int
    478 wdc_atapi_start(struct ata_channel *chp, struct ata_xfer *xfer)
    479 {
    480 	struct atac_softc *atac = chp->ch_atac;
    481 	struct wdc_softc *wdc = CHAN_TO_WDC(chp);
    482 	struct wdc_regs *wdr = &wdc->regs[chp->ch_channel];
    483 	struct scsipi_xfer *sc_xfer = xfer->c_scsipi;
    484 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->c_drive];
    485 	int wait_flags = (sc_xfer->xs_control & XS_CTL_POLL) ? AT_POLL : 0;
    486 	int tfd;
    487 	const char *errstring;
    488 
    489 	ATADEBUG_PRINT(("wdc_atapi_start %s:%d:%d, scsi flags 0x%x \n",
    490 	    device_xname(atac->atac_dev), chp->ch_channel, drvp->drive,
    491 	    sc_xfer->xs_control), DEBUG_XFERS);
    492 
    493 	ata_channel_lock_owned(chp);
    494 
    495 #if NATA_DMA
    496 	if ((xfer->c_flags & C_DMA) && (drvp->n_xfers <= NXFER))
    497 		drvp->n_xfers++;
    498 #endif
    499 	/* Do control operations specially. */
    500 	if (__predict_false(drvp->state < READY)) {
    501 		/* If it's not a polled command, we need the kernel thread */
    502 		if ((sc_xfer->xs_control & XS_CTL_POLL) == 0
    503 		    && !ata_is_thread_run(chp))
    504 			return ATASTART_TH;
    505 		/*
    506 		 * disable interrupts, all commands here should be quick
    507 		 * enough to be able to poll, and we don't go here that often
    508 		 */
    509 		bus_space_write_1(wdr->ctl_iot, wdr->ctl_ioh, wd_aux_ctlr,
    510 		     WDCTL_4BIT | WDCTL_IDS);
    511 		if (wdc->select)
    512 			wdc->select(chp, xfer->c_drive);
    513 		bus_space_write_1(wdr->cmd_iot, wdr->cmd_iohs[wd_sdh], 0,
    514 		    WDSD_IBM | (xfer->c_drive << 4));
    515 		/* Don't try to set mode if controller can't be adjusted */
    516 		if (atac->atac_set_modes == NULL)
    517 			goto ready;
    518 		/* Also don't try if the drive didn't report its mode */
    519 		if ((drvp->drive_flags & ATA_DRIVE_MODE) == 0)
    520 			goto ready;
    521 		errstring = "unbusy";
    522 		if (wdc_wait_for_unbusy(chp, ATAPI_DELAY, wait_flags, &tfd))
    523 			goto timeout;
    524 		wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
    525 		    0x08 | drvp->PIO_mode, WDSF_SET_MODE);
    526 		errstring = "piomode";
    527 		if (wdc_wait_for_unbusy(chp, ATAPI_MODE_DELAY, wait_flags,
    528 		    &tfd))
    529 			goto timeout;
    530 		if (ATACH_ST(tfd) & WDCS_ERR) {
    531 			if (ATACH_ST(tfd) == WDCE_ABRT) {
    532 				/*
    533 				 * Some ATAPI drives reject PIO settings.
    534 				 * Fall back to PIO mode 3 since that's the
    535 				 * minimum for ATAPI.
    536 				 */
    537 				printf("%s:%d:%d: PIO mode %d rejected, "
    538 				    "falling back to PIO mode 3\n",
    539 				    device_xname(atac->atac_dev),
    540 				    chp->ch_channel, xfer->c_drive,
    541 				    drvp->PIO_mode);
    542 				if (drvp->PIO_mode > 3)
    543 					drvp->PIO_mode = 3;
    544 			} else
    545 				goto error;
    546 		}
    547 #if NATA_DMA
    548 #if NATA_UDMA
    549 		if (drvp->drive_flags & ATA_DRIVE_UDMA) {
    550 			wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
    551 			    0x40 | drvp->UDMA_mode, WDSF_SET_MODE);
    552 		} else
    553 #endif
    554 		if (drvp->drive_flags & ATA_DRIVE_DMA) {
    555 			wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
    556 			    0x20 | drvp->DMA_mode, WDSF_SET_MODE);
    557 		} else {
    558 			goto ready;
    559 		}
    560 		errstring = "dmamode";
    561 		if (wdc_wait_for_unbusy(chp, ATAPI_MODE_DELAY, wait_flags,
    562 		    &tfd))
    563 			goto timeout;
    564 		if (ATACH_ST(tfd) & WDCS_ERR) {
    565 			if (ATACH_ERR(tfd) == WDCE_ABRT) {
    566 #if NATA_UDMA
    567 				if (drvp->drive_flags & ATA_DRIVE_UDMA)
    568 					goto error;
    569 				else
    570 #endif
    571 				{
    572 					/*
    573 					 * The drive rejected our DMA setting.
    574 					 * Fall back to mode 1.
    575 					 */
    576 					printf("%s:%d:%d: DMA mode %d rejected, "
    577 					    "falling back to DMA mode 0\n",
    578 					    device_xname(atac->atac_dev),
    579 					    chp->ch_channel, xfer->c_drive,
    580 					    drvp->DMA_mode);
    581 					if (drvp->DMA_mode > 0)
    582 						drvp->DMA_mode = 0;
    583 				}
    584 			} else
    585 				goto error;
    586 		}
    587 #endif	/* NATA_DMA */
    588 ready:
    589 		drvp->state = READY;
    590 		bus_space_write_1(wdr->ctl_iot, wdr->ctl_ioh, wd_aux_ctlr,
    591 		    WDCTL_4BIT);
    592 		delay(10); /* some drives need a little delay here */
    593 	}
    594 	/* start timeout machinery */
    595 	if ((sc_xfer->xs_control & XS_CTL_POLL) == 0)
    596 		callout_reset(&chp->c_timo_callout, mstohz(sc_xfer->timeout),
    597 		    wdctimeout, chp);
    598 
    599 	if (wdc->select)
    600 		wdc->select(chp, xfer->c_drive);
    601 	bus_space_write_1(wdr->cmd_iot, wdr->cmd_iohs[wd_sdh], 0,
    602 	    WDSD_IBM | (xfer->c_drive << 4));
    603 	switch (wdc_wait_for_unbusy(chp, ATAPI_DELAY, wait_flags, &tfd)) {
    604 	case WDCWAIT_OK:
    605 		break;
    606 	case WDCWAIT_TOUT:
    607 		printf("wdc_atapi_start: not ready, st = %02x\n",
    608 		    ATACH_ST(tfd));
    609 		sc_xfer->error = XS_TIMEOUT;
    610 		return ATASTART_ABORT;
    611 	case WDCWAIT_THR:
    612 		return ATASTART_TH;
    613 	}
    614 
    615 	/*
    616 	 * Even with WDCS_ERR, the device should accept a command packet
    617 	 * Limit length to what can be stuffed into the cylinder register
    618 	 * (16 bits).  Some CD-ROMs seem to interpret '0' as 65536,
    619 	 * but not all devices do that and it's not obvious from the
    620 	 * ATAPI spec that that behaviour should be expected.  If more
    621 	 * data is necessary, multiple data transfer phases will be done.
    622 	 */
    623 
    624 	wdccommand(chp, xfer->c_drive, ATAPI_PKT_CMD,
    625 	    xfer->c_bcount <= 0xffff ? xfer->c_bcount : 0xffff,
    626 	    0, 0, 0,
    627 #if NATA_DMA
    628 	    (xfer->c_flags & C_DMA) ? ATAPI_PKT_CMD_FTRE_DMA :
    629 #endif
    630 	    0
    631 	    );
    632 
    633 #if NATA_PIOBM
    634 	if (xfer->c_flags & C_PIOBM) {
    635 		int error;
    636 		int dma_flags = (sc_xfer->xs_control & XS_CTL_DATA_IN)
    637 		    ?  WDC_DMA_READ : 0;
    638 		if (xfer->c_flags & C_POLL) {
    639 			/* XXX not supported yet --- fall back to PIO */
    640 			xfer->c_flags &= ~C_PIOBM;
    641 		} else {
    642 			/* Init the DMA channel. */
    643 			error = (*wdc->dma_init)(wdc->dma_arg,
    644 			    chp->ch_channel, xfer->c_drive,
    645 			    (char *)xfer->c_databuf,
    646 			    xfer->c_bcount,
    647 			    dma_flags | WDC_DMA_PIOBM_ATAPI);
    648 			if (error) {
    649 				if (error == EINVAL) {
    650 					/*
    651 					 * We can't do DMA on this transfer
    652 					 * for some reason.  Fall back to
    653 					 * PIO.
    654 					 */
    655 					xfer->c_flags &= ~C_PIOBM;
    656 					error = 0;
    657 				} else {
    658 					sc_xfer->error = XS_DRIVER_STUFFUP;
    659 					errstring = "piobm";
    660 					goto error;
    661 				}
    662 			}
    663 		}
    664 	}
    665 #endif
    666 	/*
    667 	 * If there is no interrupt for CMD input, busy-wait for it (done in
    668 	 * the interrupt routine. Poll routine will exit early in this case.
    669 	 */
    670 	if ((sc_xfer->xs_periph->periph_cap & ATAPI_CFG_DRQ_MASK) !=
    671 	    ATAPI_CFG_IRQ_DRQ || (sc_xfer->xs_control & XS_CTL_POLL))
    672 		return ATASTART_POLL;
    673 	else {
    674 		chp->ch_flags |= ATACH_IRQ_WAIT;
    675 		return ATASTART_STARTED;
    676 	}
    677 
    678 timeout:
    679 	printf("%s:%d:%d: %s timed out\n",
    680 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
    681 	    errstring);
    682 	sc_xfer->error = XS_TIMEOUT;
    683 	bus_space_write_1(wdr->ctl_iot, wdr->ctl_ioh, wd_aux_ctlr, WDCTL_4BIT);
    684 	delay(10); /* some drives need a little delay here */
    685 	return ATASTART_ABORT;
    686 
    687 error:
    688 	printf("%s:%d:%d: %s ",
    689 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
    690 	    errstring);
    691 	printf("error (0x%x)\n", ATACH_ERR(tfd));
    692 	sc_xfer->error = XS_SHORTSENSE;
    693 	sc_xfer->sense.atapi_sense = ATACH_ERR(tfd);
    694 	bus_space_write_1(wdr->ctl_iot, wdr->ctl_ioh, wd_aux_ctlr, WDCTL_4BIT);
    695 	delay(10); /* some drives need a little delay here */
    696 	return ATASTART_ABORT;
    697 }
    698 
    699 static int
    700 wdc_atapi_poll(struct ata_channel *chp, struct ata_xfer *xfer)
    701 {
    702 	/*
    703 	 * If there is no interrupt for CMD input, busy-wait for it (done in
    704 	 * the interrupt routine. If it is a polled command, call the interrupt
    705 	 * routine until command is done.
    706 	 */
    707 	const bool poll = ((xfer->c_scsipi->xs_control & XS_CTL_POLL) != 0);
    708 
    709 	/* Wait for at last 400ns for status bit to be valid */
    710 	DELAY(1);
    711 	wdc_atapi_intr(chp, xfer, 0);
    712 
    713 	if (!poll)
    714 		return ATAPOLL_DONE;
    715 
    716 #if NATA_DMA
    717 	if (chp->ch_flags & ATACH_DMA_WAIT) {
    718 		wdc_dmawait(chp, xfer, xfer->c_scsipi->timeout);
    719 		chp->ch_flags &= ~ATACH_DMA_WAIT;
    720 	}
    721 #endif
    722 	while ((xfer->c_scsipi->xs_status & XS_STS_DONE) == 0) {
    723 		/* Wait for at last 400ns for status bit to be valid */
    724 		DELAY(1);
    725 		wdc_atapi_intr(chp, xfer, 0);
    726 	}
    727 
    728 	return ATAPOLL_DONE;
    729 }
    730 
    731 static int
    732 wdc_atapi_intr(struct ata_channel *chp, struct ata_xfer *xfer, int irq)
    733 {
    734 	struct atac_softc *atac = chp->ch_atac;
    735 	struct wdc_softc *wdc = CHAN_TO_WDC(chp);
    736 	struct wdc_regs *wdr = &wdc->regs[chp->ch_channel];
    737 	struct scsipi_xfer *sc_xfer = xfer->c_scsipi;
    738 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->c_drive];
    739 	int len, phase, i, retries=0;
    740 	int ire, tfd;
    741 #if NATA_DMA
    742 	int error;
    743 #endif
    744 #if NATA_DMA || NATA_PIOBM
    745 	int dma_flags = 0;
    746 #endif
    747 	void *cmd;
    748 
    749 	ATADEBUG_PRINT(("wdc_atapi_intr %s:%d:%d\n",
    750 	    device_xname(atac->atac_dev), chp->ch_channel, drvp->drive),
    751 	    DEBUG_INTR);
    752 
    753 	ata_channel_lock(chp);
    754 
    755 	/* Is it not a transfer, but a control operation? */
    756 	if (drvp->state < READY) {
    757 		printf("%s:%d:%d: bad state %d in wdc_atapi_intr\n",
    758 		    device_xname(atac->atac_dev), chp->ch_channel,
    759 		    xfer->c_drive, drvp->state);
    760 		panic("wdc_atapi_intr: bad state");
    761 	}
    762 	/*
    763 	 * If we missed an interrupt in a PIO transfer, reset and restart.
    764 	 * Don't try to continue transfer, we may have missed cycles.
    765 	 */
    766 	if ((xfer->c_flags & (C_TIMEOU | C_DMA)) == C_TIMEOU) {
    767 		ata_channel_unlock(chp);
    768 		sc_xfer->error = XS_TIMEOUT;
    769 		wdc_atapi_reset(chp, xfer);
    770 		return 1;
    771 	}
    772 
    773 #if NATA_PIOBM
    774 	/* Transfer-done interrupt for busmastering PIO operation */
    775 	if ((xfer->c_flags & C_PIOBM) && (chp->ch_flags & ATACH_PIOBM_WAIT)) {
    776 		chp->ch_flags &= ~ATACH_PIOBM_WAIT;
    777 
    778 		/* restore transfer length */
    779 		len = xfer->c_bcount;
    780 		if (xfer->c_atapi.c_lenoff < 0)
    781 			len += xfer->c_atapi.c_lenoff;
    782 
    783 		if (sc_xfer->xs_control & XS_CTL_DATA_IN)
    784 			goto end_piobm_datain;
    785 		else
    786 			goto end_piobm_dataout;
    787 	}
    788 #endif
    789 
    790 	/* Ack interrupt done in wdc_wait_for_unbusy */
    791 	if (wdc->select)
    792 		wdc->select(chp, xfer->c_drive);
    793 	bus_space_write_1(wdr->cmd_iot, wdr->cmd_iohs[wd_sdh], 0,
    794 	    WDSD_IBM | (xfer->c_drive << 4));
    795 	if (wdc_wait_for_unbusy(chp,
    796 	    (irq == 0) ? sc_xfer->timeout : 0, AT_POLL, &tfd) == WDCWAIT_TOUT) {
    797 		if (irq && (xfer->c_flags & C_TIMEOU) == 0) {
    798 			ata_channel_unlock(chp);
    799 			return 0; /* IRQ was not for us */
    800 		}
    801 		printf("%s:%d:%d: device timeout, c_bcount=%d, c_skip=%d\n",
    802 		    device_xname(atac->atac_dev), chp->ch_channel,
    803 		    xfer->c_drive, xfer->c_bcount, xfer->c_skip);
    804 #if NATA_DMA
    805 		if (xfer->c_flags & C_DMA) {
    806 			ata_dmaerr(drvp,
    807 			    (xfer->c_flags & C_POLL) ? AT_POLL : 0);
    808 		}
    809 #endif
    810 		sc_xfer->error = XS_TIMEOUT;
    811 		ata_channel_unlock(chp);
    812 		wdc_atapi_reset(chp, xfer);
    813 		return 1;
    814 	}
    815 	if (wdc->irqack)
    816 		wdc->irqack(chp);
    817 
    818 #if NATA_DMA
    819 	/*
    820 	 * If we missed an IRQ and were using DMA, flag it as a DMA error
    821 	 * and reset device.
    822 	 */
    823 	if ((xfer->c_flags & C_TIMEOU) && (xfer->c_flags & C_DMA)) {
    824 		ata_dmaerr(drvp, (xfer->c_flags & C_POLL) ? AT_POLL : 0);
    825 		sc_xfer->error = XS_RESET;
    826 		ata_channel_unlock(chp);
    827 		wdc_atapi_reset(chp, xfer);
    828 		return (1);
    829 	}
    830 #endif
    831 	/*
    832 	 * if the request sense command was aborted, report the short sense
    833 	 * previously recorded, else continue normal processing
    834 	 */
    835 
    836 #if NATA_DMA || NATA_PIOBM
    837 	if (xfer->c_flags & (C_DMA | C_PIOBM))
    838 		dma_flags = (sc_xfer->xs_control & XS_CTL_DATA_IN)
    839 		    ?  WDC_DMA_READ : 0;
    840 #endif
    841 again:
    842 	len = bus_space_read_1(wdr->cmd_iot, wdr->cmd_iohs[wd_cyl_lo], 0) +
    843 	    256 * bus_space_read_1(wdr->cmd_iot, wdr->cmd_iohs[wd_cyl_hi], 0);
    844 	ire = bus_space_read_1(wdr->cmd_iot, wdr->cmd_iohs[wd_ireason], 0);
    845 	phase = (ire & (WDCI_CMD | WDCI_IN)) | (ATACH_ST(tfd) & WDCS_DRQ);
    846 	ATADEBUG_PRINT(("wdc_atapi_intr: c_bcount %d len %d st 0x%x err 0x%x "
    847 	    "ire 0x%x :", xfer->c_bcount,
    848 	    len, ATACH_ST(tfd), ATACH_ERR(tfd), ire), DEBUG_INTR);
    849 
    850 	switch (phase) {
    851 	case PHASE_CMDOUT:
    852 		cmd = sc_xfer->cmd;
    853 		ATADEBUG_PRINT(("PHASE_CMDOUT\n"), DEBUG_INTR);
    854 #if NATA_DMA
    855 		/* Init the DMA channel if necessary */
    856 		if (xfer->c_flags & C_DMA) {
    857 			error = (*wdc->dma_init)(wdc->dma_arg,
    858 			    chp->ch_channel, xfer->c_drive,
    859 			    xfer->c_databuf, xfer->c_bcount, dma_flags);
    860 			if (error) {
    861 				if (error == EINVAL) {
    862 					/*
    863 					 * We can't do DMA on this transfer
    864 					 * for some reason.  Fall back to
    865 					 * PIO.
    866 					 */
    867 					xfer->c_flags &= ~C_DMA;
    868 					error = 0;
    869 				} else {
    870 					sc_xfer->error = XS_DRIVER_STUFFUP;
    871 					break;
    872 				}
    873 			}
    874 		}
    875 #endif
    876 
    877 		/* send packet command */
    878 		/* Commands are 12 or 16 bytes long. It's 32-bit aligned */
    879 		wdc->dataout_pio(chp, drvp->drive_flags, cmd, sc_xfer->cmdlen);
    880 
    881 #if NATA_DMA
    882 		/* Start the DMA channel if necessary */
    883 		if (xfer->c_flags & C_DMA) {
    884 			(*wdc->dma_start)(wdc->dma_arg,
    885 			    chp->ch_channel, xfer->c_drive);
    886 			chp->ch_flags |= ATACH_DMA_WAIT;
    887 		}
    888 #endif
    889 
    890 		if ((sc_xfer->xs_control & XS_CTL_POLL) == 0) {
    891 			chp->ch_flags |= ATACH_IRQ_WAIT;
    892 		}
    893 
    894 		ata_channel_unlock(chp);
    895 		return 1;
    896 
    897 	 case PHASE_DATAOUT:
    898 		/* write data */
    899 		ATADEBUG_PRINT(("PHASE_DATAOUT\n"), DEBUG_INTR);
    900 #if NATA_DMA
    901 		if ((sc_xfer->xs_control & XS_CTL_DATA_OUT) == 0 ||
    902 		    (xfer->c_flags & C_DMA) != 0) {
    903 			printf("wdc_atapi_intr: bad data phase DATAOUT\n");
    904 			if (xfer->c_flags & C_DMA) {
    905 				ata_dmaerr(drvp,
    906 				    (xfer->c_flags & C_POLL) ? AT_POLL : 0);
    907 			}
    908 			sc_xfer->error = XS_TIMEOUT;
    909 			ata_channel_unlock(chp);
    910 			wdc_atapi_reset(chp, xfer);
    911 			return 1;
    912 		}
    913 #endif
    914 		xfer->c_atapi.c_lenoff = len - xfer->c_bcount;
    915 		if (xfer->c_bcount < len) {
    916 			printf("wdc_atapi_intr: warning: write only "
    917 			    "%d of %d requested bytes\n", xfer->c_bcount, len);
    918 			len = xfer->c_bcount;
    919 		}
    920 
    921 #if NATA_PIOBM
    922 		if (xfer->c_flags & C_PIOBM) {
    923 			/* start the busmastering PIO */
    924 			(*wdc->piobm_start)(wdc->dma_arg,
    925 			    chp->ch_channel, xfer->c_drive,
    926 			    xfer->c_skip, len, WDC_PIOBM_XFER_IRQ);
    927 			chp->ch_flags |= ATACH_DMA_WAIT | ATACH_IRQ_WAIT |
    928 			    ATACH_PIOBM_WAIT;
    929 			ata_channel_unlock(chp);
    930 			return 1;
    931 		}
    932 #endif
    933 		wdc->dataout_pio(chp, drvp->drive_flags,
    934 		    (char *)xfer->c_databuf + xfer->c_skip, len);
    935 
    936 #if NATA_PIOBM
    937 	end_piobm_dataout:
    938 #endif
    939 		for (i = xfer->c_atapi.c_lenoff; i > 0; i -= 2)
    940 			bus_space_write_2(wdr->cmd_iot,
    941 			    wdr->cmd_iohs[wd_data], 0, 0);
    942 
    943 		xfer->c_skip += len;
    944 		xfer->c_bcount -= len;
    945 		if ((sc_xfer->xs_control & XS_CTL_POLL) == 0) {
    946 			chp->ch_flags |= ATACH_IRQ_WAIT;
    947 		}
    948 		ata_channel_unlock(chp);
    949 		return 1;
    950 
    951 	case PHASE_DATAIN:
    952 		/* Read data */
    953 		ATADEBUG_PRINT(("PHASE_DATAIN\n"), DEBUG_INTR);
    954 #if NATA_DMA
    955 		if ((sc_xfer->xs_control & XS_CTL_DATA_IN) == 0 ||
    956 		    (xfer->c_flags & C_DMA) != 0) {
    957 			printf("wdc_atapi_intr: bad data phase DATAIN\n");
    958 			if (xfer->c_flags & C_DMA) {
    959 				ata_dmaerr(drvp,
    960 				    (xfer->c_flags & C_POLL) ? AT_POLL : 0);
    961 			}
    962 			sc_xfer->error = XS_TIMEOUT;
    963 			ata_channel_unlock(chp);
    964 			wdc_atapi_reset(chp, xfer);
    965 			return 1;
    966 		}
    967 #endif
    968 		xfer->c_atapi.c_lenoff = len - xfer->c_bcount;
    969 		if (xfer->c_bcount < len) {
    970 			printf("wdc_atapi_intr: warning: reading only "
    971 			    "%d of %d bytes\n", xfer->c_bcount, len);
    972 			len = xfer->c_bcount;
    973 		}
    974 
    975 #if NATA_PIOBM
    976 		if (xfer->c_flags & C_PIOBM) {
    977 			/* start the busmastering PIO */
    978 			(*wdc->piobm_start)(wdc->dma_arg,
    979 			    chp->ch_channel, xfer->c_drive,
    980 			    xfer->c_skip, len, WDC_PIOBM_XFER_IRQ);
    981 			chp->ch_flags |= ATACH_DMA_WAIT | ATACH_IRQ_WAIT |
    982 			    ATACH_PIOBM_WAIT;
    983 			ata_channel_unlock(chp);
    984 			return 1;
    985 		}
    986 #endif
    987 		wdc->datain_pio(chp, drvp->drive_flags,
    988 		    (char *)xfer->c_databuf + xfer->c_skip, len);
    989 
    990 #if NATA_PIOBM
    991 	end_piobm_datain:
    992 #endif
    993 		if (xfer->c_atapi.c_lenoff > 0)
    994 			wdcbit_bucket(chp, xfer->c_atapi.c_lenoff);
    995 
    996 		xfer->c_skip += len;
    997 		xfer->c_bcount -= len;
    998 		if ((sc_xfer->xs_control & XS_CTL_POLL) == 0) {
    999 			chp->ch_flags |= ATACH_IRQ_WAIT;
   1000 		}
   1001 		ata_channel_unlock(chp);
   1002 		return 1;
   1003 
   1004 	case PHASE_ABORTED:
   1005 	case PHASE_COMPLETED:
   1006 		ATADEBUG_PRINT(("PHASE_COMPLETED\n"), DEBUG_INTR);
   1007 #if NATA_DMA
   1008 		if (xfer->c_flags & C_DMA) {
   1009 			xfer->c_bcount -= sc_xfer->datalen;
   1010 		}
   1011 #endif
   1012 		sc_xfer->resid = xfer->c_bcount;
   1013 		/* this will unlock channel lock too */
   1014 		wdc_atapi_phase_complete(xfer, tfd);
   1015 		return(1);
   1016 
   1017 	default:
   1018 		if (++retries<500) {
   1019 			DELAY(100);
   1020 			tfd = ATACH_ERR_ST(
   1021 			    bus_space_read_1(wdr->cmd_iot,
   1022 				wdr->cmd_iohs[wd_error], 0),
   1023 			    bus_space_read_1(wdr->cmd_iot,
   1024 				wdr->cmd_iohs[wd_status], 0)
   1025 			);
   1026 			goto again;
   1027 		}
   1028 		printf("wdc_atapi_intr: unknown phase 0x%x\n", phase);
   1029 		if (ATACH_ST(tfd) & WDCS_ERR) {
   1030 			sc_xfer->error = XS_SHORTSENSE;
   1031 			sc_xfer->sense.atapi_sense = ATACH_ERR(tfd);
   1032 		} else {
   1033 #if NATA_DMA
   1034 			if (xfer->c_flags & C_DMA) {
   1035 				ata_dmaerr(drvp,
   1036 				    (xfer->c_flags & C_POLL) ? AT_POLL : 0);
   1037 			}
   1038 #endif
   1039 			sc_xfer->error = XS_RESET;
   1040 			ata_channel_unlock(chp);
   1041 			wdc_atapi_reset(chp, xfer);
   1042 			return (1);
   1043 		}
   1044 	}
   1045 	ATADEBUG_PRINT(("wdc_atapi_intr: wdc_atapi_done() (end), error 0x%x "
   1046 	    "sense 0x%x\n", sc_xfer->error, sc_xfer->sense.atapi_sense),
   1047 	    DEBUG_INTR);
   1048 	ata_channel_unlock(chp);
   1049 	wdc_atapi_done(chp, xfer);
   1050 	return (1);
   1051 }
   1052 
   1053 static void
   1054 wdc_atapi_phase_complete(struct ata_xfer *xfer, int tfd)
   1055 {
   1056 	struct ata_channel *chp = xfer->c_chp;
   1057 	struct atac_softc *atac = chp->ch_atac;
   1058 #if NATA_DMA || NATA_PIOBM
   1059 	struct wdc_softc *wdc = CHAN_TO_WDC(chp);
   1060 #endif
   1061 	struct scsipi_xfer *sc_xfer = xfer->c_scsipi;
   1062 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->c_drive];
   1063 
   1064 	ata_channel_lock_owned(chp);
   1065 
   1066 	/* wait for DSC if needed */
   1067 	if (drvp->drive_flags & ATA_DRIVE_ATAPIDSCW) {
   1068 		ATADEBUG_PRINT(("wdc_atapi_phase_complete(%s:%d:%d) "
   1069 		    "polldsc %d\n", device_xname(atac->atac_dev),
   1070 		    chp->ch_channel,
   1071 		    xfer->c_drive, xfer->c_atapi.c_dscpoll), DEBUG_XFERS);
   1072 #if 1
   1073 		if (cold)
   1074 			panic("wdc_atapi_phase_complete: cold");
   1075 #endif
   1076 		if (wdcwait(chp, WDCS_DSC, WDCS_DSC, 10,
   1077 		    AT_POLL, &tfd) == WDCWAIT_TOUT) {
   1078 			/* 10ms not enough, try again in 1 tick */
   1079 			if (xfer->c_atapi.c_dscpoll++ >
   1080 			    mstohz(sc_xfer->timeout)) {
   1081 				printf("%s:%d:%d: wait_for_dsc "
   1082 				    "failed\n",
   1083 				    device_xname(atac->atac_dev),
   1084 				    chp->ch_channel, xfer->c_drive);
   1085 				ata_channel_unlock(chp);
   1086 				sc_xfer->error = XS_TIMEOUT;
   1087 				wdc_atapi_reset(chp, xfer);
   1088 			} else {
   1089 				callout_reset(&chp->c_timo_callout, 1,
   1090 				    wdc_atapi_polldsc, chp);
   1091 				ata_channel_unlock(chp);
   1092 			}
   1093 			return;
   1094 		}
   1095 	}
   1096 
   1097 	/*
   1098 	 * Some drive occasionally set WDCS_ERR with
   1099 	 * "ATA illegal length indication" in the error
   1100 	 * register. If we read some data the sense is valid
   1101 	 * anyway, so don't report the error.
   1102 	 */
   1103 	if (ATACH_ST(tfd) & WDCS_ERR &&
   1104 	    ((sc_xfer->xs_control & XS_CTL_REQSENSE) == 0 ||
   1105 	    sc_xfer->resid == sc_xfer->datalen)) {
   1106 		/* save the short sense */
   1107 		sc_xfer->error = XS_SHORTSENSE;
   1108 		sc_xfer->sense.atapi_sense = ATACH_ERR(tfd);
   1109 		if ((sc_xfer->xs_periph->periph_quirks &
   1110 		    PQUIRK_NOSENSE) == 0) {
   1111 			/* ask scsipi to send a REQUEST_SENSE */
   1112 			sc_xfer->error = XS_BUSY;
   1113 			sc_xfer->status = SCSI_CHECK;
   1114 		}
   1115 #if NATA_DMA || NATA_PIOBM
   1116 		else if (wdc->dma_status &
   1117 		    (WDC_DMAST_NOIRQ | WDC_DMAST_ERR)) {
   1118 #if NATA_DMA
   1119 			ata_dmaerr(drvp,
   1120 			    (xfer->c_flags & C_POLL) ? AT_POLL : 0);
   1121 #endif
   1122 			sc_xfer->error = XS_RESET;
   1123 			ata_channel_unlock(chp);
   1124 			wdc_atapi_reset(chp, xfer);
   1125 			return;
   1126 		}
   1127 #endif
   1128 	}
   1129 	if (xfer->c_bcount != 0) {
   1130 		ATADEBUG_PRINT(("wdc_atapi_intr: bcount value is "
   1131 		    "%d after io\n", xfer->c_bcount), DEBUG_XFERS);
   1132 	}
   1133 #ifdef DIAGNOSTIC
   1134 	if (xfer->c_bcount < 0) {
   1135 		printf("wdc_atapi_intr warning: bcount value "
   1136 		    "is %d after io\n", xfer->c_bcount);
   1137 	}
   1138 #endif
   1139 	ATADEBUG_PRINT(("wdc_atapi_phase_complete: wdc_atapi_done(), "
   1140 	    "error 0x%x sense 0x%x\n", sc_xfer->error,
   1141 	    sc_xfer->sense.atapi_sense), DEBUG_INTR);
   1142 	ata_channel_unlock(chp);
   1143 	wdc_atapi_done(chp, xfer);
   1144 }
   1145 
   1146 static void
   1147 wdc_atapi_done(struct ata_channel *chp, struct ata_xfer *xfer)
   1148 {
   1149 	struct atac_softc *atac = chp->ch_atac;
   1150 	struct scsipi_xfer *sc_xfer = xfer->c_scsipi;
   1151 
   1152 	ATADEBUG_PRINT(("wdc_atapi_done %s:%d:%d: flags 0x%x\n",
   1153 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
   1154 	    (u_int)xfer->c_flags), DEBUG_XFERS);
   1155 
   1156 	if (ata_waitdrain_xfer_check(chp, xfer))
   1157 		return;
   1158 
   1159 	ata_deactivate_xfer(chp, xfer);
   1160 	ata_free_xfer(chp, xfer);
   1161 
   1162 	ATADEBUG_PRINT(("wdc_atapi_done: scsipi_done\n"), DEBUG_XFERS);
   1163 	scsipi_done(sc_xfer);
   1164 	ATADEBUG_PRINT(("atastart from wdc_atapi_done, flags 0x%x\n",
   1165 	    chp->ch_flags), DEBUG_XFERS);
   1166 	atastart(chp);
   1167 }
   1168 
   1169 static void
   1170 wdc_atapi_reset(struct ata_channel *chp, struct ata_xfer *xfer)
   1171 {
   1172 	struct atac_softc *atac = chp->ch_atac;
   1173 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->c_drive];
   1174 	struct scsipi_xfer *sc_xfer = xfer->c_scsipi;
   1175 	int tfd;
   1176 
   1177 	ata_channel_lock(chp);
   1178 	wdccommandshort(chp, xfer->c_drive, ATAPI_SOFT_RESET);
   1179 	drvp->state = 0;
   1180 	if (wdc_wait_for_unbusy(chp, WDC_RESET_WAIT, AT_POLL, &tfd) != 0) {
   1181 		printf("%s:%d:%d: reset failed\n",
   1182 		    device_xname(atac->atac_dev), chp->ch_channel,
   1183 		    xfer->c_drive);
   1184 		sc_xfer->error = XS_SELTIMEOUT;
   1185 	}
   1186 	ata_channel_unlock(chp);
   1187 	wdc_atapi_done(chp, xfer);
   1188 	return;
   1189 }
   1190 
   1191 static void
   1192 wdc_atapi_polldsc(void *arg)
   1193 {
   1194 	struct ata_channel *chp = arg;
   1195 	struct ata_xfer *xfer = ata_queue_get_active_xfer(chp);
   1196 
   1197 	KASSERT(xfer != NULL);
   1198 
   1199 	ata_channel_lock(chp);
   1200 
   1201 	/* this will unlock channel lock too */
   1202 	wdc_atapi_phase_complete(xfer, 0);
   1203 }
   1204