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ata_wdc.c revision 1.105.6.4
      1 /*	$NetBSD: ata_wdc.c,v 1.105.6.4 2017/06/16 20:40:49 jdolecek Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1998, 2001, 2003 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 /*-
     28  * Copyright (c) 1998, 2004 The NetBSD Foundation, Inc.
     29  * All rights reserved.
     30  *
     31  * This code is derived from software contributed to The NetBSD Foundation
     32  * by Charles M. Hannum, by Onno van der Linden and by Manuel Bouyer.
     33  *
     34  * Redistribution and use in source and binary forms, with or without
     35  * modification, are permitted provided that the following conditions
     36  * are met:
     37  * 1. Redistributions of source code must retain the above copyright
     38  *    notice, this list of conditions and the following disclaimer.
     39  * 2. Redistributions in binary form must reproduce the above copyright
     40  *    notice, this list of conditions and the following disclaimer in the
     41  *    documentation and/or other materials provided with the distribution.
     42  *
     43  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     44  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     45  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     46  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     47  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     48  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     49  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     50  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     51  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     52  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     53  * POSSIBILITY OF SUCH DAMAGE.
     54  */
     55 
     56 #include <sys/cdefs.h>
     57 __KERNEL_RCSID(0, "$NetBSD: ata_wdc.c,v 1.105.6.4 2017/06/16 20:40:49 jdolecek Exp $");
     58 
     59 #include "opt_ata.h"
     60 #include "opt_wdc.h"
     61 
     62 #include <sys/param.h>
     63 #include <sys/systm.h>
     64 #include <sys/kernel.h>
     65 #include <sys/file.h>
     66 #include <sys/stat.h>
     67 #include <sys/buf.h>
     68 #include <sys/bufq.h>
     69 #include <sys/malloc.h>
     70 #include <sys/device.h>
     71 #include <sys/disklabel.h>
     72 #include <sys/syslog.h>
     73 #include <sys/proc.h>
     74 
     75 #include <sys/intr.h>
     76 #include <sys/bus.h>
     77 #ifndef __BUS_SPACE_HAS_STREAM_METHODS
     78 #define    bus_space_write_multi_stream_2    bus_space_write_multi_2
     79 #define    bus_space_write_multi_stream_4    bus_space_write_multi_4
     80 #define    bus_space_read_multi_stream_2    bus_space_read_multi_2
     81 #define    bus_space_read_multi_stream_4    bus_space_read_multi_4
     82 #endif /* __BUS_SPACE_HAS_STREAM_METHODS */
     83 
     84 #include <dev/ata/ataconf.h>
     85 #include <dev/ata/atareg.h>
     86 #include <dev/ata/atavar.h>
     87 #include <dev/ic/wdcreg.h>
     88 #include <dev/ic/wdcvar.h>
     89 
     90 #define DEBUG_INTR   0x01
     91 #define DEBUG_XFERS  0x02
     92 #define DEBUG_STATUS 0x04
     93 #define DEBUG_FUNCS  0x08
     94 #define DEBUG_PROBE  0x10
     95 #ifdef ATADEBUG
     96 extern int wdcdebug_wd_mask; /* inited in wd.c */
     97 #define ATADEBUG_PRINT(args, level) \
     98 	if (wdcdebug_wd_mask & (level)) \
     99 		printf args
    100 #else
    101 #define ATADEBUG_PRINT(args, level)
    102 #endif
    103 
    104 #define ATA_DELAY 10000 /* 10s for a drive I/O */
    105 
    106 static int	wdc_ata_bio(struct ata_drive_datas*, struct ata_xfer *);
    107 static void	wdc_ata_bio_start(struct ata_channel *,struct ata_xfer *);
    108 static void	_wdc_ata_bio_start(struct ata_channel *,struct ata_xfer *);
    109 static int	wdc_ata_bio_intr(struct ata_channel *, struct ata_xfer *,
    110 				 int);
    111 static void	wdc_ata_bio_kill_xfer(struct ata_channel *,
    112 				      struct ata_xfer *, int);
    113 static void	wdc_ata_bio_done(struct ata_channel *, struct ata_xfer *);
    114 static int	wdc_ata_err(struct ata_drive_datas *, struct ata_bio *);
    115 #define WDC_ATA_NOERR 0x00 /* Drive doesn't report an error */
    116 #define WDC_ATA_RECOV 0x01 /* There was a recovered error */
    117 #define WDC_ATA_ERR   0x02 /* Drive reports an error */
    118 static int	wdc_ata_addref(struct ata_drive_datas *);
    119 static void	wdc_ata_delref(struct ata_drive_datas *);
    120 
    121 const struct ata_bustype wdc_ata_bustype = {
    122 	SCSIPI_BUSTYPE_ATA,
    123 	wdc_ata_bio,
    124 	wdc_reset_drive,
    125 	wdc_reset_channel,
    126 	wdc_exec_command,
    127 	ata_get_params,
    128 	wdc_ata_addref,
    129 	wdc_ata_delref,
    130 	ata_kill_pending,
    131 };
    132 
    133 /*
    134  * Handle block I/O operation. Return ATACMD_COMPLETE, ATACMD_QUEUED, or
    135  * ATACMD_TRY_AGAIN. Must be called at splbio().
    136  */
    137 static int
    138 wdc_ata_bio(struct ata_drive_datas *drvp, struct ata_xfer *xfer)
    139 {
    140 	struct ata_channel *chp = drvp->chnl_softc;
    141 	struct atac_softc *atac = chp->ch_atac;
    142 	struct ata_bio *ata_bio = &xfer->c_bio;
    143 
    144 	if (atac->atac_cap & ATAC_CAP_NOIRQ)
    145 		ata_bio->flags |= ATA_POLL;
    146 	if (ata_bio->flags & ATA_POLL)
    147 		xfer->c_flags |= C_POLL;
    148 #if NATA_DMA
    149 	if ((drvp->drive_flags & (ATA_DRIVE_DMA | ATA_DRIVE_UDMA)) &&
    150 	    (ata_bio->flags & ATA_SINGLE) == 0)
    151 		xfer->c_flags |= C_DMA;
    152 #endif
    153 #if NATA_DMA && NATA_PIOBM
    154 	else
    155 #endif
    156 #if NATA_PIOBM
    157 	if (atac->atac_cap & ATAC_CAP_PIOBM)
    158 		xfer->c_flags |= C_PIOBM;
    159 #endif
    160 	xfer->c_drive = drvp->drive;
    161 	xfer->c_databuf = ata_bio->databuf;
    162 	xfer->c_bcount = ata_bio->bcount;
    163 	xfer->c_start = wdc_ata_bio_start;
    164 	xfer->c_intr = wdc_ata_bio_intr;
    165 	xfer->c_kill_xfer = wdc_ata_bio_kill_xfer;
    166 	ata_exec_xfer(chp, xfer);
    167 	return (ata_bio->flags & ATA_ITSDONE) ? ATACMD_COMPLETE : ATACMD_QUEUED;
    168 }
    169 
    170 static void
    171 wdc_ata_bio_start(struct ata_channel *chp, struct ata_xfer *xfer)
    172 {
    173 	struct atac_softc *atac = chp->ch_atac;
    174 	struct wdc_softc *wdc = CHAN_TO_WDC(chp);
    175 	struct wdc_regs *wdr = &wdc->regs[chp->ch_channel];
    176 	struct ata_bio *ata_bio = &xfer->c_bio;
    177 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->c_drive];
    178 	int wait_flags;
    179 	const char *errstring;
    180 #ifdef WDC_NO_IDS
    181 	wait_flags = AT_POLL;
    182 #else
    183 	wait_flags = (xfer->c_flags & C_POLL) ? AT_POLL : 0;
    184 #endif
    185 
    186 	ATADEBUG_PRINT(("wdc_ata_bio_start %s:%d:%d state %d drive_flags 0x%x "
    187 	    "c_flags 0x%x ch_flags 0x%x\n",
    188 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
    189 	    drvp->state, drvp->drive_flags, xfer->c_flags, chp->ch_flags),
    190 	    DEBUG_XFERS);
    191 
    192 	/* Do control operations specially. */
    193 	if (__predict_false(drvp->state < READY)) {
    194 		/*
    195 		 * Actually, we want to be careful not to mess with the control
    196 		 * state if the device is currently busy, but we can assume
    197 		 * that we never get to this point if that's the case.
    198 		 */
    199 		/* If it's not a polled command, we need the kernel thread */
    200 		if ((xfer->c_flags & C_POLL) == 0 &&
    201 		    (chp->ch_flags & ATACH_TH_RUN) == 0) {
    202 			chp->ch_queue->queue_freeze++;
    203 			wakeup(&chp->ch_thread);
    204 			return;
    205 		}
    206 		/*
    207 		 * disable interrupts, all commands here should be quick
    208 		 * enough to be able to poll, and we don't go here that often
    209 		 */
    210 		if (! (wdc->cap & WDC_CAPABILITY_NO_AUXCTL))
    211 			bus_space_write_1(wdr->ctl_iot, wdr->ctl_ioh,
    212 			    wd_aux_ctlr, WDCTL_4BIT | WDCTL_IDS);
    213 		if (wdc->select)
    214 			wdc->select(chp, xfer->c_drive);
    215 		bus_space_write_1(wdr->cmd_iot, wdr->cmd_iohs[wd_sdh], 0,
    216 		    WDSD_IBM | (xfer->c_drive << 4));
    217 		DELAY(10);
    218 		errstring = "wait";
    219 		if (wdcwait(chp, WDCS_DRDY, WDCS_DRDY, ATA_DELAY, wait_flags))
    220 			goto ctrltimeout;
    221 		wdccommandshort(chp, xfer->c_drive, WDCC_RECAL);
    222 		/* Wait for at last 400ns for status bit to be valid */
    223 		DELAY(1);
    224 		errstring = "recal";
    225 		if (wdcwait(chp, WDCS_DRDY, WDCS_DRDY, ATA_DELAY, wait_flags))
    226 			goto ctrltimeout;
    227 		if (chp->ch_status & (WDCS_ERR | WDCS_DWF))
    228 			goto ctrlerror;
    229 		/* Don't try to set modes if controller can't be adjusted */
    230 		if (atac->atac_set_modes == NULL)
    231 			goto geometry;
    232 		/* Also don't try if the drive didn't report its mode */
    233 		if ((drvp->drive_flags & ATA_DRIVE_MODE) == 0)
    234 			goto geometry;
    235 		wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
    236 		    0x08 | drvp->PIO_mode, WDSF_SET_MODE);
    237 		errstring = "piomode";
    238 		if (wdcwait(chp, WDCS_DRDY, WDCS_DRDY, ATA_DELAY, wait_flags))
    239 			goto ctrltimeout;
    240 		if (chp->ch_status & (WDCS_ERR | WDCS_DWF))
    241 			goto ctrlerror;
    242 #if NATA_DMA
    243 #if NATA_UDMA
    244 		if (drvp->drive_flags & ATA_DRIVE_UDMA) {
    245 			wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
    246 			    0x40 | drvp->UDMA_mode, WDSF_SET_MODE);
    247 		} else
    248 #endif
    249 		if (drvp->drive_flags & ATA_DRIVE_DMA) {
    250 			wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
    251 			    0x20 | drvp->DMA_mode, WDSF_SET_MODE);
    252 		} else {
    253 			goto geometry;
    254 		}
    255 		errstring = "dmamode";
    256 		if (wdcwait(chp, WDCS_DRDY, WDCS_DRDY, ATA_DELAY, wait_flags))
    257 			goto ctrltimeout;
    258 		if (chp->ch_status & (WDCS_ERR | WDCS_DWF))
    259 			goto ctrlerror;
    260 #endif	/* NATA_DMA */
    261 geometry:
    262 		if (ata_bio->flags & ATA_LBA)
    263 			goto multimode;
    264 		wdccommand(chp, xfer->c_drive, WDCC_IDP,
    265 		    drvp->lp->d_ncylinders,
    266 		    drvp->lp->d_ntracks - 1, 0, drvp->lp->d_nsectors,
    267 		    (drvp->lp->d_type == DKTYPE_ST506) ?
    268 			drvp->lp->d_precompcyl / 4 : 0);
    269 		errstring = "geometry";
    270 		if (wdcwait(chp, WDCS_DRDY, WDCS_DRDY, ATA_DELAY, wait_flags))
    271 			goto ctrltimeout;
    272 		if (chp->ch_status & (WDCS_ERR | WDCS_DWF))
    273 			goto ctrlerror;
    274 multimode:
    275 		if (drvp->multi == 1)
    276 			goto ready;
    277 		wdccommand(chp, xfer->c_drive, WDCC_SETMULTI, 0, 0, 0,
    278 		    drvp->multi, 0);
    279 		errstring = "setmulti";
    280 		if (wdcwait(chp, WDCS_DRDY, WDCS_DRDY, ATA_DELAY, wait_flags))
    281 			goto ctrltimeout;
    282 		if (chp->ch_status & (WDCS_ERR | WDCS_DWF))
    283 			goto ctrlerror;
    284 ready:
    285 		drvp->state = READY;
    286 		/*
    287 		 * The drive is usable now
    288 		 */
    289 		if (! (wdc->cap & WDC_CAPABILITY_NO_AUXCTL))
    290 			bus_space_write_1(wdr->ctl_iot, wdr->ctl_ioh,
    291 			    wd_aux_ctlr, WDCTL_4BIT);
    292 		delay(10); /* some drives need a little delay here */
    293 	}
    294 
    295 	_wdc_ata_bio_start(chp, xfer);
    296 	return;
    297 ctrltimeout:
    298 	printf("%s:%d:%d: %s timed out\n",
    299 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
    300 	    errstring);
    301 	ata_bio->error = TIMEOUT;
    302 	goto ctrldone;
    303 ctrlerror:
    304 	printf("%s:%d:%d: %s ",
    305 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
    306 	    errstring);
    307 	if (chp->ch_status & WDCS_DWF) {
    308 		printf("drive fault\n");
    309 		ata_bio->error = ERR_DF;
    310 	} else {
    311 		printf("error (%x)\n", chp->ch_error);
    312 		ata_bio->r_error = chp->ch_error;
    313 		ata_bio->error = ERROR;
    314 	}
    315 ctrldone:
    316 	drvp->state = 0;
    317 	wdc_ata_bio_done(chp, xfer);
    318 
    319 	if (! (wdc->cap & WDC_CAPABILITY_NO_AUXCTL))
    320 		bus_space_write_1(wdr->ctl_iot, wdr->ctl_ioh, wd_aux_ctlr,
    321 		    WDCTL_4BIT);
    322 	return;
    323 }
    324 
    325 static void
    326 _wdc_ata_bio_start(struct ata_channel *chp, struct ata_xfer *xfer)
    327 {
    328 	struct atac_softc *atac = chp->ch_atac;
    329 	struct wdc_softc *wdc = CHAN_TO_WDC(chp);
    330 	struct wdc_regs *wdr = &wdc->regs[chp->ch_channel];
    331 	struct ata_bio *ata_bio = &xfer->c_bio;
    332 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->c_drive];
    333 	int wait_flags = (xfer->c_flags & C_POLL) ? AT_POLL : 0;
    334 	uint16_t cyl;
    335 	uint8_t head, sect, cmd = 0;
    336 	int nblks;
    337 #if NATA_DMA || NATA_PIOBM
    338 	int error, dma_flags = 0;
    339 #endif
    340 
    341 	ATADEBUG_PRINT(("_wdc_ata_bio_start %s:%d:%d\n",
    342 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive),
    343 	    DEBUG_INTR | DEBUG_XFERS);
    344 
    345 #if NATA_DMA || NATA_PIOBM
    346 	if (xfer->c_flags & (C_DMA | C_PIOBM)) {
    347 #if NATA_DMA
    348 		if (drvp->n_xfers <= NXFER)
    349 			drvp->n_xfers++;
    350 #endif
    351 		dma_flags = (ata_bio->flags & ATA_READ) ?  WDC_DMA_READ : 0;
    352 		if (ata_bio->flags & ATA_LBA48)
    353 			dma_flags |= WDC_DMA_LBA48;
    354 	}
    355 #endif
    356 again:
    357 	/*
    358 	 *
    359 	 * When starting a multi-sector transfer, or doing single-sector
    360 	 * transfers...
    361 	 */
    362 	if (xfer->c_skip == 0 || (ata_bio->flags & ATA_SINGLE) != 0) {
    363 		if (ata_bio->flags & ATA_SINGLE)
    364 			nblks = 1;
    365 		else
    366 			nblks = xfer->c_bcount / drvp->lp->d_secsize;
    367 		/* Check for bad sectors and adjust transfer, if necessary. */
    368 		if ((drvp->lp->d_flags & D_BADSECT) != 0) {
    369 			long blkdiff;
    370 			int i;
    371 			for (i = 0; (blkdiff = drvp->badsect[i]) != -1;
    372 			    i++) {
    373 				blkdiff -= ata_bio->blkno;
    374 				if (blkdiff < 0)
    375 					continue;
    376 				if (blkdiff == 0) {
    377 					/* Replace current block of transfer. */
    378 					ata_bio->blkno =
    379 					    drvp->lp->d_secperunit -
    380 					    drvp->lp->d_nsectors - i - 1;
    381 				}
    382 				if (blkdiff < nblks) {
    383 					/* Bad block inside transfer. */
    384 					ata_bio->flags |= ATA_SINGLE;
    385 					nblks = 1;
    386 				}
    387 				break;
    388 			}
    389 		/* Transfer is okay now. */
    390 		}
    391 		if (ata_bio->flags & ATA_LBA48) {
    392 			sect = 0;
    393 			cyl =  0;
    394 			head = 0;
    395 		} else if (ata_bio->flags & ATA_LBA) {
    396 			sect = (ata_bio->blkno >> 0) & 0xff;
    397 			cyl = (ata_bio->blkno >> 8) & 0xffff;
    398 			head = (ata_bio->blkno >> 24) & 0x0f;
    399 			head |= WDSD_LBA;
    400 		} else {
    401 			int blkno = ata_bio->blkno;
    402 			sect = blkno % drvp->lp->d_nsectors;
    403 			sect++;    /* Sectors begin with 1, not 0. */
    404 			blkno /= drvp->lp->d_nsectors;
    405 			head = blkno % drvp->lp->d_ntracks;
    406 			blkno /= drvp->lp->d_ntracks;
    407 			cyl = blkno;
    408 			head |= WDSD_CHS;
    409 		}
    410 #if NATA_DMA
    411 		if (xfer->c_flags & C_DMA) {
    412 			uint16_t count = nblks, features = 0;
    413 
    414 			ata_bio->nblks = nblks;
    415 			ata_bio->nbytes = xfer->c_bcount;
    416 			cmd = (ata_bio->flags & ATA_READ) ?
    417 			    WDCC_READDMA : WDCC_WRITEDMA;
    418 	    		/* Init the DMA channel. */
    419 			error = (*wdc->dma_init)(wdc->dma_arg,
    420 			    chp->ch_channel, xfer->c_drive,
    421 			    (char *)xfer->c_databuf + xfer->c_skip,
    422 			    ata_bio->nbytes, dma_flags);
    423 			if (error) {
    424 				if (error == EINVAL) {
    425 					/*
    426 					 * We can't do DMA on this transfer
    427 					 * for some reason.  Fall back to
    428 					 * PIO.
    429 					 */
    430 					xfer->c_flags &= ~C_DMA;
    431 					error = 0;
    432 					goto do_pio;
    433 				}
    434 				ata_bio->error = ERR_DMA;
    435 				ata_bio->r_error = 0;
    436 				wdc_ata_bio_done(chp, xfer);
    437 				return;
    438 			}
    439 			/* Initiate command */
    440 			if (wdc->select)
    441 				wdc->select(chp, xfer->c_drive);
    442 			bus_space_write_1(wdr->cmd_iot, wdr->cmd_iohs[wd_sdh],
    443 			    0, WDSD_IBM | (xfer->c_drive << 4));
    444 			switch(wdc_wait_for_ready(chp, ATA_DELAY, wait_flags)) {
    445 			case WDCWAIT_OK:
    446 				break;
    447 			case WDCWAIT_TOUT:
    448 				goto timeout;
    449 			case WDCWAIT_THR:
    450 				return;
    451 			}
    452 			if (ata_bio->flags & ATA_LBA48) {
    453 			    uint8_t device = WDSD_LBA;
    454 			    cmd = atacmd_to48(cmd);
    455 
    456 			    atacmd_toncq(xfer, &cmd, &count, &features,
    457 			        &device);
    458 
    459 			    wdccommandext(chp, xfer->c_drive, cmd,
    460 				ata_bio->blkno, count, features, device);
    461 			} else {
    462 			    wdccommand(chp, xfer->c_drive, cmd, cyl,
    463 				head, sect, count, features);
    464 			}
    465 			/* start the DMA channel */
    466 			(*wdc->dma_start)(wdc->dma_arg,
    467 			    chp->ch_channel, xfer->c_drive);
    468 			chp->ch_flags |= ATACH_DMA_WAIT;
    469 			/* start timeout machinery */
    470 			if ((xfer->c_flags & C_POLL) == 0)
    471 				callout_reset(&xfer->c_timo_callout,
    472 				    ATA_DELAY / 1000 * hz, wdctimeout, xfer);
    473 			/* wait for irq */
    474 			goto intr;
    475 		} /* else not DMA */
    476  do_pio:
    477 #endif	/* NATA_DMA */
    478 #if NATA_PIOBM
    479 		if ((xfer->c_flags & C_PIOBM) && xfer->c_skip == 0) {
    480 			if (ata_bio->flags & ATA_POLL) {
    481 				/* XXX not supported yet --- fall back to PIO */
    482 				xfer->c_flags &= ~C_PIOBM;
    483 			} else {
    484 				/* Init the DMA channel. */
    485 				error = (*wdc->dma_init)(wdc->dma_arg,
    486 				    chp->ch_channel, xfer->c_drive,
    487 				    (char *)xfer->c_databuf + xfer->c_skip,
    488 				    xfer->c_bcount,
    489 				    dma_flags | WDC_DMA_PIOBM_ATA);
    490 				if (error) {
    491 					if (error == EINVAL) {
    492 						/*
    493 						 * We can't do DMA on this
    494 						 * transfer for some reason.
    495 						 * Fall back to PIO.
    496 						 */
    497 						xfer->c_flags &= ~C_PIOBM;
    498 						error = 0;
    499 					} else {
    500 						ata_bio->error = ERR_DMA;
    501 						ata_bio->r_error = 0;
    502 						wdc_ata_bio_done(chp, xfer);
    503 						return;
    504 					}
    505 				}
    506 			}
    507 		}
    508 #endif
    509 		ata_bio->nblks = min(nblks, drvp->multi);
    510 		ata_bio->nbytes = ata_bio->nblks * drvp->lp->d_secsize;
    511 		KASSERT(nblks == 1 || (ata_bio->flags & ATA_SINGLE) == 0);
    512 		if (ata_bio->nblks > 1) {
    513 			cmd = (ata_bio->flags & ATA_READ) ?
    514 			    WDCC_READMULTI : WDCC_WRITEMULTI;
    515 		} else {
    516 			cmd = (ata_bio->flags & ATA_READ) ?
    517 			    WDCC_READ : WDCC_WRITE;
    518 		}
    519 		/* Initiate command! */
    520 		if (wdc->select)
    521 			wdc->select(chp, xfer->c_drive);
    522 		bus_space_write_1(wdr->cmd_iot, wdr->cmd_iohs[wd_sdh], 0,
    523 		    WDSD_IBM | (xfer->c_drive << 4));
    524 		switch(wdc_wait_for_ready(chp, ATA_DELAY, wait_flags)) {
    525 		case WDCWAIT_OK:
    526 			break;
    527 		case WDCWAIT_TOUT:
    528 			goto timeout;
    529 		case WDCWAIT_THR:
    530 			return;
    531 		}
    532 		if (ata_bio->flags & ATA_LBA48) {
    533 		    wdccommandext(chp, xfer->c_drive, atacmd_to48(cmd),
    534 			ata_bio->blkno, nblks, 0, WDSD_LBA);
    535 		} else {
    536 		    wdccommand(chp, xfer->c_drive, cmd, cyl,
    537 			head, sect, nblks,
    538 			(drvp->lp->d_type == DKTYPE_ST506) ?
    539 			drvp->lp->d_precompcyl / 4 : 0);
    540 		}
    541 		/* start timeout machinery */
    542 		if ((xfer->c_flags & C_POLL) == 0)
    543 			callout_reset(&xfer->c_timo_callout,
    544 			    ATA_DELAY / 1000 * hz, wdctimeout, xfer);
    545 	} else if (ata_bio->nblks > 1) {
    546 		/* The number of blocks in the last stretch may be smaller. */
    547 		nblks = xfer->c_bcount / drvp->lp->d_secsize;
    548 		if (ata_bio->nblks > nblks) {
    549 		ata_bio->nblks = nblks;
    550 		ata_bio->nbytes = xfer->c_bcount;
    551 		}
    552 	}
    553 	/* If this was a write and not using DMA, push the data. */
    554 	if ((ata_bio->flags & ATA_READ) == 0) {
    555 		/*
    556 		 * we have to busy-wait here, we can't rely on running in
    557 		 * thread context.
    558 		 */
    559 		if (wdc_wait_for_drq(chp, ATA_DELAY, AT_POLL) != 0) {
    560 			printf("%s:%d:%d: timeout waiting for DRQ, "
    561 			    "st=0x%02x, err=0x%02x\n",
    562 			    device_xname(atac->atac_dev), chp->ch_channel,
    563 			    xfer->c_drive, chp->ch_status, chp->ch_error);
    564 			if (wdc_ata_err(drvp, ata_bio) != WDC_ATA_ERR)
    565 				ata_bio->error = TIMEOUT;
    566 			wdc_ata_bio_done(chp, xfer);
    567 			return;
    568 		}
    569 		if (wdc_ata_err(drvp, ata_bio) == WDC_ATA_ERR) {
    570 			wdc_ata_bio_done(chp, xfer);
    571 			return;
    572 		}
    573 #if NATA_PIOBM
    574 		if (xfer->c_flags & C_PIOBM) {
    575 			/* start the busmastering PIO */
    576 			(*wdc->piobm_start)(wdc->dma_arg,
    577 			    chp->ch_channel, xfer->c_drive,
    578 			    xfer->c_skip, ata_bio->nbytes, 0);
    579 			chp->ch_flags |= ATACH_DMA_WAIT;
    580 		} else
    581 #endif
    582 
    583 		wdc->dataout_pio(chp, drvp->drive_flags,
    584 		    (char *)xfer->c_databuf + xfer->c_skip, ata_bio->nbytes);
    585 	}
    586 
    587 #if NATA_DMA
    588 intr:
    589 #endif
    590 	/* Wait for IRQ (either real or polled) */
    591 	if ((ata_bio->flags & ATA_POLL) == 0) {
    592 		chp->ch_flags |= ATACH_IRQ_WAIT;
    593 	} else {
    594 		/* Wait for at last 400ns for status bit to be valid */
    595 		delay(1);
    596 #if NATA_DMA
    597 		if (chp->ch_flags & ATACH_DMA_WAIT) {
    598 			wdc_dmawait(chp, xfer, ATA_DELAY);
    599 			chp->ch_flags &= ~ATACH_DMA_WAIT;
    600 		}
    601 #endif
    602 		wdc_ata_bio_intr(chp, xfer, 0);
    603 		if ((ata_bio->flags & ATA_ITSDONE) == 0)
    604 			goto again;
    605 	}
    606 	return;
    607 timeout:
    608 	printf("%s:%d:%d: not ready, st=0x%02x, err=0x%02x\n",
    609 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
    610 	    chp->ch_status, chp->ch_error);
    611 	if (wdc_ata_err(drvp, ata_bio) != WDC_ATA_ERR)
    612 		ata_bio->error = TIMEOUT;
    613 	wdc_ata_bio_done(chp, xfer);
    614 	return;
    615 }
    616 
    617 static int
    618 wdc_ata_bio_intr(struct ata_channel *chp, struct ata_xfer *xfer, int irq)
    619 {
    620 	struct atac_softc *atac = chp->ch_atac;
    621 	struct wdc_softc *wdc = CHAN_TO_WDC(chp);
    622 	struct ata_bio *ata_bio = &xfer->c_bio;
    623 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->c_drive];
    624 	int drv_err;
    625 
    626 	ATADEBUG_PRINT(("wdc_ata_bio_intr %s:%d:%d\n",
    627 	    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive),
    628 	    DEBUG_INTR | DEBUG_XFERS);
    629 
    630 
    631 	/* Is it not a transfer, but a control operation? */
    632 	if (drvp->state < READY) {
    633 		printf("%s:%d:%d: bad state %d in wdc_ata_bio_intr\n",
    634 		    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
    635 		    drvp->state);
    636 		panic("wdc_ata_bio_intr: bad state");
    637 	}
    638 
    639 	/*
    640 	 * if we missed an interrupt in a PIO transfer, reset and restart.
    641 	 * Don't try to continue transfer, we may have missed cycles.
    642 	 */
    643 	if ((xfer->c_flags & (C_TIMEOU | C_DMA)) == C_TIMEOU) {
    644 		ata_bio->error = TIMEOUT;
    645 		wdc_ata_bio_done(chp, xfer);
    646 		return 1;
    647 	}
    648 
    649 #if NATA_PIOBM
    650 	/* Transfer-done interrupt for busmastering PIO read */
    651 	if ((xfer->c_flags & C_PIOBM) && (chp->ch_flags & ATACH_PIOBM_WAIT)) {
    652 		chp->ch_flags &= ~ATACH_PIOBM_WAIT;
    653 		goto end;
    654 	}
    655 #endif
    656 
    657 	/* Ack interrupt done by wdc_wait_for_unbusy */
    658 	if (wdc_wait_for_unbusy(chp, (irq == 0) ? ATA_DELAY : 0, AT_POLL) < 0) {
    659 		if (irq && (xfer->c_flags & C_TIMEOU) == 0)
    660 			return 0; /* IRQ was not for us */
    661 		printf("%s:%d:%d: device timeout, c_bcount=%d, c_skip%d\n",
    662 		    device_xname(atac->atac_dev), chp->ch_channel, xfer->c_drive,
    663 		    xfer->c_bcount, xfer->c_skip);
    664 		ata_bio->error = TIMEOUT;
    665 		wdc_ata_bio_done(chp, xfer);
    666 		return 1;
    667 	}
    668 	if (wdc->irqack)
    669 		wdc->irqack(chp);
    670 
    671 	drv_err = wdc_ata_err(drvp, ata_bio);
    672 
    673 #if NATA_DMA
    674 	/* If we were using DMA, Turn off the DMA channel and check for error */
    675 	if (xfer->c_flags & C_DMA) {
    676 		if (ata_bio->flags & ATA_POLL) {
    677 			/*
    678 			 * IDE drives deassert WDCS_BSY before transfer is
    679 			 * complete when using DMA. Polling for DRQ to deassert
    680 			 * is not enough DRQ is not required to be
    681 			 * asserted for DMA transfers, so poll for DRDY.
    682 			 */
    683 			if (wdcwait(chp, WDCS_DRDY | WDCS_DRQ, WDCS_DRDY,
    684 			    ATA_DELAY, ATA_POLL) == WDCWAIT_TOUT) {
    685 				printf("%s:%d:%d: polled transfer timed out "
    686 				    "(st=0x%x)\n",
    687 				    device_xname(atac->atac_dev),
    688 				    chp->ch_channel, xfer->c_drive,
    689 				    chp->ch_status);
    690 				ata_bio->error = TIMEOUT;
    691 				drv_err = WDC_ATA_ERR;
    692 			}
    693 		}
    694 		if (wdc->dma_status != 0) {
    695 			if (drv_err != WDC_ATA_ERR) {
    696 				ata_bio->error = ERR_DMA;
    697 				drv_err = WDC_ATA_ERR;
    698 			}
    699 		}
    700 		if (chp->ch_status & WDCS_DRQ) {
    701 			if (drv_err != WDC_ATA_ERR) {
    702 				printf("%s:%d:%d: intr with DRQ (st=0x%x)\n",
    703 				    device_xname(atac->atac_dev),
    704 				    chp->ch_channel,
    705 				    xfer->c_drive, chp->ch_status);
    706 				ata_bio->error = TIMEOUT;
    707 				drv_err = WDC_ATA_ERR;
    708 			}
    709 		}
    710 		if (drv_err != WDC_ATA_ERR)
    711 			goto end;
    712 		if (ata_bio->r_error & WDCE_CRC || ata_bio->error == ERR_DMA)
    713 			ata_dmaerr(drvp, (xfer->c_flags & C_POLL) ? AT_POLL : 0);
    714 	}
    715 #endif	/* NATA_DMA */
    716 
    717 	/* if we had an error, end */
    718 	if (drv_err == WDC_ATA_ERR) {
    719 		wdc_ata_bio_done(chp, xfer);
    720 		return 1;
    721 	}
    722 
    723 	/* If this was a read and not using DMA, fetch the data. */
    724 	if ((ata_bio->flags & ATA_READ) != 0) {
    725 		if ((chp->ch_status & WDCS_DRQ) != WDCS_DRQ) {
    726 			printf("%s:%d:%d: read intr before drq\n",
    727 			    device_xname(atac->atac_dev), chp->ch_channel,
    728 			    xfer->c_drive);
    729 			ata_bio->error = TIMEOUT;
    730 			wdc_ata_bio_done(chp, xfer);
    731 			return 1;
    732 		}
    733 #if NATA_PIOBM
    734 		if (xfer->c_flags & C_PIOBM) {
    735 			/* start the busmastering PIO */
    736 			(*wdc->piobm_start)(wdc->dma_arg,
    737 			    chp->ch_channel, xfer->c_drive,
    738 			    xfer->c_skip, ata_bio->nbytes,
    739 			    WDC_PIOBM_XFER_IRQ);
    740 			chp->ch_flags |= ATACH_DMA_WAIT | ATACH_PIOBM_WAIT | ATACH_IRQ_WAIT;
    741 			return 1;
    742 		} else
    743 #endif
    744 		wdc->datain_pio(chp, drvp->drive_flags,
    745 		    (char *)xfer->c_databuf + xfer->c_skip, ata_bio->nbytes);
    746 	}
    747 
    748 #if NATA_DMA || NATA_PIOBM
    749 end:
    750 #endif
    751 	ata_bio->blkno += ata_bio->nblks;
    752 	ata_bio->blkdone += ata_bio->nblks;
    753 	xfer->c_skip += ata_bio->nbytes;
    754 	xfer->c_bcount -= ata_bio->nbytes;
    755 	/* See if this transfer is complete. */
    756 	if (xfer->c_bcount > 0) {
    757 		if ((ata_bio->flags & ATA_POLL) == 0) {
    758 			/* Start the next operation */
    759 			_wdc_ata_bio_start(chp, xfer);
    760 		} else {
    761 			/* Let _wdc_ata_bio_start do the loop */
    762 			return 1;
    763 		}
    764 	} else { /* Done with this transfer */
    765 		ata_bio->error = NOERROR;
    766 		wdc_ata_bio_done(chp, xfer);
    767 	}
    768 	return 1;
    769 }
    770 
    771 static void
    772 wdc_ata_bio_kill_xfer(struct ata_channel *chp, struct ata_xfer *xfer,
    773     int reason)
    774 {
    775 	struct ata_bio *ata_bio = &xfer->c_bio;
    776 	int drive = xfer->c_drive;
    777 
    778 	ata_deactivate_xfer(chp, xfer);
    779 
    780 	ata_bio->flags |= ATA_ITSDONE;
    781 	switch (reason) {
    782 	case KILL_GONE:
    783 		ata_bio->error = ERR_NODEV;
    784 		break;
    785 	case KILL_RESET:
    786 		ata_bio->error = ERR_RESET;
    787 		break;
    788 	default:
    789 		printf("wdc_ata_bio_kill_xfer: unknown reason %d\n",
    790 		    reason);
    791 		panic("wdc_ata_bio_kill_xfer");
    792 	}
    793 	ata_bio->r_error = WDCE_ABRT;
    794 	ATADEBUG_PRINT(("wdc_ata_bio_kill_xfer: drv_done\n"), DEBUG_XFERS);
    795 	(*chp->ch_drive[drive].drv_done)(chp->ch_drive[drive].drv_softc, xfer);
    796 }
    797 
    798 static void
    799 wdc_ata_bio_done(struct ata_channel *chp, struct ata_xfer *xfer)
    800 {
    801 	struct ata_bio *ata_bio = &xfer->c_bio;
    802 	int drive = xfer->c_drive;
    803 
    804 	ATADEBUG_PRINT(("wdc_ata_bio_done %s:%d:%d: flags 0x%x\n",
    805 	    device_xname(chp->ch_atac->atac_dev), chp->ch_channel,
    806 	    xfer->c_drive, (u_int)xfer->c_flags),
    807 	    DEBUG_XFERS);
    808 
    809 	callout_stop(&xfer->c_timo_callout);
    810 
    811 	/* feed back residual bcount to our caller */
    812 	ata_bio->bcount = xfer->c_bcount;
    813 
    814 	/* mark controller inactive and free xfer */
    815 	ata_deactivate_xfer(chp, xfer);
    816 
    817 	if (ata_waitdrain_check(chp, drive)) {
    818 		ata_bio->error = ERR_NODEV;
    819 	}
    820 	ata_bio->flags |= ATA_ITSDONE;
    821 	ATADEBUG_PRINT(("wdc_ata_done: drv_done\n"), DEBUG_XFERS);
    822 	(*chp->ch_drive[drive].drv_done)(chp->ch_drive[drive].drv_softc, xfer);
    823 	ATADEBUG_PRINT(("atastart from wdc_ata_done, flags 0x%x\n",
    824 	    chp->ch_flags), DEBUG_XFERS);
    825 	atastart(chp);
    826 }
    827 
    828 static int
    829 wdc_ata_err(struct ata_drive_datas *drvp, struct ata_bio *ata_bio)
    830 {
    831 	struct ata_channel *chp = drvp->chnl_softc;
    832 	ata_bio->error = 0;
    833 	if (chp->ch_status & WDCS_BSY) {
    834 		ata_bio->error = TIMEOUT;
    835 		return WDC_ATA_ERR;
    836 	}
    837 
    838 	if (chp->ch_status & WDCS_DWF) {
    839 		ata_bio->error = ERR_DF;
    840 		return WDC_ATA_ERR;
    841 	}
    842 
    843 	if (chp->ch_status & WDCS_ERR) {
    844 		ata_bio->error = ERROR;
    845 		ata_bio->r_error = chp->ch_error;
    846 		if (ata_bio->r_error & (WDCE_BBK | WDCE_UNC | WDCE_IDNF |
    847 		    WDCE_ABRT | WDCE_TK0NF | WDCE_AMNF))
    848 			return WDC_ATA_ERR;
    849 		return WDC_ATA_NOERR;
    850 	}
    851 
    852 	if (chp->ch_status & WDCS_CORR)
    853 		ata_bio->flags |= ATA_CORR;
    854 	return WDC_ATA_NOERR;
    855 }
    856 
    857 static int
    858 wdc_ata_addref(struct ata_drive_datas *drvp)
    859 {
    860 	struct ata_channel *chp = drvp->chnl_softc;
    861 
    862 	return (ata_addref(chp));
    863 }
    864 
    865 static void
    866 wdc_ata_delref(struct ata_drive_datas *drvp)
    867 {
    868 	struct ata_channel *chp = drvp->chnl_softc;
    869 
    870 	ata_delref(chp);
    871 }
    872