Home | History | Annotate | Line # | Download | only in ic
ninjaata32.c revision 1.2
      1 /*	$Id: ninjaata32.c,v 1.2 2006/10/01 09:53:09 itohy Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2006 ITOH Yasufumi <itohy (at) NetBSD.org>.
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS''
     17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
     18  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS
     20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
     26  * THE POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 #include <sys/cdefs.h>
     30 __KERNEL_RCSID(0, "$NetBSD: ninjaata32.c,v 1.2 2006/10/01 09:53:09 itohy Exp $");
     31 
     32 #include <sys/param.h>
     33 #include <sys/kernel.h>
     34 #include <sys/device.h>
     35 
     36 #include <machine/bus.h>
     37 #include <machine/intr.h>
     38 
     39 #include <uvm/uvm_extern.h>
     40 
     41 #include <dev/ata/atavar.h>
     42 #include <dev/ic/wdcreg.h>
     43 #include <dev/ic/wdcvar.h>
     44 
     45 #include <dev/ic/ninjaata32reg.h>
     46 #include <dev/ic/ninjaata32var.h>
     47 
     48 #ifdef NJATA32_DEBUG
     49 #define DPRINTF(x)	printf x
     50 #else
     51 #define DPRINTF(x)
     52 #endif
     53 
     54 static void	njata32_init(struct njata32_softc *, int nosleep);
     55 static void	njata32_irqack(struct ata_channel *);
     56 static void	njata32_clearirq(struct ata_channel *, int);
     57 static void	njata32_setup_channel(struct ata_channel *);
     58 static int	njata32_dma_init(void *, int channel, int drive,
     59 		    void *databuf, size_t datalen, int flags);
     60 static void	njata32_piobm_start(void *, int channel, int drive, int skip,
     61 		    int xferlen, int flags);
     62 static int	njata32_dma_finish(void *, int channel, int drive, int force);
     63 static void	njata32_piobm_done(void *, int channel, int drive);
     64 
     65 #if 0	/* ATA DMA is currently unused */
     66 static const uint8_t njata32_timing_dma[NJATA32_MODE_MAX_DMA + 1] = {
     67 	NJATA32_TIMING_DMA0, NJATA32_TIMING_DMA1, NJATA32_TIMING_DMA2
     68 };
     69 #endif
     70 static const uint8_t njata32_timing_pio[NJATA32_MODE_MAX_PIO + 1] = {
     71 	NJATA32_TIMING_PIO0, NJATA32_TIMING_PIO1, NJATA32_TIMING_PIO2,
     72 	NJATA32_TIMING_PIO3, NJATA32_TIMING_PIO4
     73 };
     74 
     75 static void
     76 njata32_init(sc, nosleep)
     77 	struct njata32_softc *sc;
     78 	int nosleep;	/* can't sleep (during cold boot and in interrupt) */
     79 {
     80 
     81 	/* disable interrupts */
     82 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
     83 	    NJATA32_REG_IRQ_SELECT, 0);
     84 
     85 	/* bus reset */
     86 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_AS,
     87 	    NJATA32_AS_WAIT0 | NJATA32_AS_BUS_RESET);
     88 	if (nosleep)
     89 		delay(50000);
     90 	else
     91 		tsleep(sc, PRIBIO, "njaini", mstohz(50));
     92 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_AS,
     93 	    NJATA32_AS_WAIT0);
     94 
     95 	/* initial transfer speed */
     96 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
     97 	    NJATA32_REG_TIMING, NJATA32_TIMING_PIO0 + sc->sc_atawait);
     98 
     99 	/* setup busmaster mode */
    100 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_IOBM,
    101 	    NJATA32_IOBM_DEFAULT);
    102 
    103 	/* enable interrupts */
    104 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    105 	    NJATA32_REG_IRQ_SELECT, NJATA32_IRQ_XFER | NJATA32_IRQ_DEV);
    106 }
    107 
    108 void
    109 njata32_attach(sc)
    110 	struct njata32_softc *sc;
    111 {
    112 	bus_addr_t dmaaddr;
    113 	int i, devno, error;
    114 	struct wdc_regs *wdr;
    115 
    116 	/*
    117 	 * allocate DMA resource
    118 	 */
    119 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
    120 	    sizeof(struct njata32_dma_page), PAGE_SIZE, 0,
    121 	    &sc->sc_sgt_seg, 1, &sc->sc_sgt_nsegs, BUS_DMA_NOWAIT)) != 0) {
    122 		printf("%s: unable to allocate sgt page, error = %d\n",
    123 		    NJATA32NAME(sc), error);
    124 		return;
    125 	}
    126 	if ((error = bus_dmamem_map(sc->sc_dmat, &sc->sc_sgt_seg,
    127 	    sc->sc_sgt_nsegs, sizeof(struct njata32_dma_page),
    128 	    (caddr_t *)&sc->sc_sgtpg,
    129 	    BUS_DMA_NOWAIT | BUS_DMA_COHERENT)) != 0) {
    130 		printf("%s: unable to map sgt page, error = %d\n",
    131 		    NJATA32NAME(sc), error);
    132 		goto fail1;
    133 	}
    134 	if ((error = bus_dmamap_create(sc->sc_dmat,
    135 	    sizeof(struct njata32_dma_page), 1,
    136 	    sizeof(struct njata32_dma_page), 0, BUS_DMA_NOWAIT,
    137 	    &sc->sc_dmamap_sgt)) != 0) {
    138 		printf("%s: unable to create sgt DMA map, error = %d\n",
    139 		    NJATA32NAME(sc), error);
    140 		goto fail2;
    141 	}
    142 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_dmamap_sgt,
    143 	    sc->sc_sgtpg, sizeof(struct njata32_dma_page),
    144 	    NULL, BUS_DMA_NOWAIT)) != 0) {
    145 		printf("%s: unable to load sgt DMA map, error = %d\n",
    146 		    NJATA32NAME(sc), error);
    147 		goto fail3;
    148 	}
    149 
    150 	dmaaddr = sc->sc_dmamap_sgt->dm_segs[0].ds_addr;
    151 
    152 	for (devno = 0; devno < NJATA32_NUM_DEV; devno++) {
    153 		sc->sc_dev[devno].d_sgt = sc->sc_sgtpg->dp_sg[devno];
    154 		sc->sc_dev[devno].d_sgt_dma = dmaaddr +
    155 		    offsetof(struct njata32_dma_page, dp_sg[devno]);
    156 
    157 		error = bus_dmamap_create(sc->sc_dmat,
    158 		    NJATA32_MAX_XFER,		/* max total map size */
    159 		    NJATA32_NUM_SG,		/* max number of segments */
    160 		    NJATA32_SGT_MAXSEGLEN,	/* max size of a segment */
    161 		    0,				/* boundary */
    162 		    BUS_DMA_NOWAIT | BUS_DMA_ALLOCNOW,
    163 		    &sc->sc_dev[devno].d_dmamap_xfer);
    164 		if (error) {
    165 			printf("%s: failed to create DMA map (error = %d)\n",
    166 			    NJATA32NAME(sc), error);
    167 			goto fail4;
    168 		}
    169 	}
    170 
    171 	/* device properties */
    172 	sc->sc_wdcdev.sc_atac.atac_cap =
    173 	    ATAC_CAP_DATA16 | ATAC_CAP_DATA32 | ATAC_CAP_PIOBM;
    174 	sc->sc_wdcdev.irqack = njata32_irqack;
    175 	sc->sc_wdcdev.sc_atac.atac_channels = sc->sc_wdc_chanarray;
    176 	sc->sc_wdcdev.sc_atac.atac_nchannels = NJATA32_NCHAN;	/* 1 */
    177 	sc->sc_wdcdev.sc_atac.atac_pio_cap = NJATA32_MODE_MAX_PIO;
    178 #if 0	/* ATA DMA is currently unused */
    179 	sc->sc_wdcdev.sc_atac.atac_dma_cap = NJATA32_MODE_MAX_DMA;
    180 #endif
    181 	sc->sc_wdcdev.sc_atac.atac_set_modes = njata32_setup_channel;
    182 
    183 	/* DMA control functions */
    184 	sc->sc_wdcdev.dma_arg = sc;
    185 	sc->sc_wdcdev.dma_init = njata32_dma_init;
    186 	sc->sc_wdcdev.piobm_start = njata32_piobm_start;
    187 	sc->sc_wdcdev.dma_finish = njata32_dma_finish;
    188 	sc->sc_wdcdev.piobm_done = njata32_piobm_done;
    189 
    190 	sc->sc_wdcdev.cap |= WDC_CAPABILITY_NO_EXTRA_RESETS;
    191 
    192 	sc->sc_wdcdev.regs = wdr = &sc->sc_wdc_regs;
    193 
    194 	/* only one channel */
    195 	sc->sc_wdc_chanarray[0] = &sc->sc_ch[0].ch_ata_channel;
    196 	sc->sc_ch[0].ch_ata_channel.ch_channel = 0;
    197 	sc->sc_ch[0].ch_ata_channel.ch_atac = &sc->sc_wdcdev.sc_atac;
    198 	sc->sc_ch[0].ch_ata_channel.ch_queue = &sc->sc_wdc_chqueue;
    199 	sc->sc_ch[0].ch_ata_channel.ch_ndrive = 2; /* max number of drives */
    200 
    201 	/* map ATA registers */
    202 	for (i = 0; i < WDC_NREG; i++) {
    203 		if (bus_space_subregion(NJATA32_REGT(sc), NJATA32_REGH(sc),
    204 		    NJATA32_OFFSET_WDCREGS + i,
    205 		    i == wd_data ? 4 : 1, &wdr->cmd_iohs[i]) != 0) {
    206 			aprint_error("%s: couldn't subregion cmd regs\n",
    207 			    NJATA32NAME(sc));
    208 			goto fail4;
    209 		}
    210 	}
    211 	wdc_init_shadow_regs(&sc->sc_ch[0].ch_ata_channel);
    212 	wdr->data32iot = NJATA32_REGT(sc);
    213 	wdr->data32ioh = wdr->cmd_iohs[wd_data];
    214 
    215 	/* map ATA ctl reg */
    216 	wdr->ctl_iot = NJATA32_REGT(sc);
    217 	if (bus_space_subregion(NJATA32_REGT(sc), NJATA32_REGH(sc),
    218 	    NJATA32_REG_WD_ALTSTATUS, 1, &wdr->ctl_ioh) != 0) {
    219 		aprint_error("%s: couldn't subregion ctl regs\n",
    220 		    NJATA32NAME(sc));
    221 		goto fail4;
    222 	}
    223 
    224 	sc->sc_flags |= NJATA32_CMDPG_MAPPED;
    225 
    226 	/* use flags value as busmaster wait */
    227 	if ((sc->sc_atawait =
    228 	    (uint8_t)device_cfdata(&sc->sc_wdcdev.sc_atac.atac_dev)->cf_flags))
    229 		aprint_normal("%s: ATA wait = %#x\n",
    230 		    NJATA32NAME(sc), sc->sc_atawait);
    231 
    232 	njata32_init(sc, cold);
    233 
    234 	wdcattach(&sc->sc_ch[0].ch_ata_channel);
    235 
    236 	return;
    237 
    238 	/*
    239 	 * cleanup
    240 	 */
    241 fail4:	while (--devno >= 0) {
    242 		bus_dmamap_destroy(sc->sc_dmat,
    243 		    sc->sc_dev[devno].d_dmamap_xfer);
    244 	}
    245 	bus_dmamap_unload(sc->sc_dmat, sc->sc_dmamap_sgt);
    246 fail3:	bus_dmamap_destroy(sc->sc_dmat, sc->sc_dmamap_sgt);
    247 fail2:	bus_dmamem_unmap(sc->sc_dmat, (caddr_t)sc->sc_sgtpg,
    248 	    sizeof(struct njata32_dma_page));
    249 fail1:	bus_dmamem_free(sc->sc_dmat, &sc->sc_sgt_seg, sc->sc_sgt_nsegs);
    250 }
    251 
    252 int
    253 njata32_detach(sc, flags)
    254 	struct njata32_softc *sc;
    255 	int flags;
    256 {
    257 	int rv, devno;
    258 
    259 	if (sc->sc_flags & NJATA32_CMDPG_MAPPED) {
    260 		if ((rv = wdcdetach(&sc->sc_wdcdev.sc_atac.atac_dev, flags)))
    261 			return rv;
    262 
    263 		/* free DMA resource */
    264 		for (devno = 0; devno < NJATA32_NUM_DEV; devno++) {
    265 			bus_dmamap_destroy(sc->sc_dmat,
    266 			    sc->sc_dev[devno].d_dmamap_xfer);
    267 		}
    268 		bus_dmamap_unload(sc->sc_dmat, sc->sc_dmamap_sgt);
    269 		bus_dmamap_destroy(sc->sc_dmat, sc->sc_dmamap_sgt);
    270 		bus_dmamem_unmap(sc->sc_dmat, (caddr_t)sc->sc_sgtpg,
    271 		    sizeof(struct njata32_dma_page));
    272 		bus_dmamem_free(sc->sc_dmat, &sc->sc_sgt_seg, sc->sc_sgt_nsegs);
    273 	}
    274 
    275 	return 0;
    276 }
    277 
    278 static void
    279 njata32_irqack(chp)
    280 	struct ata_channel *chp;
    281 {
    282 	struct njata32_softc *sc = (void *)chp->ch_atac;
    283 
    284 	/* disable busmaster */
    285 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    286 	    NJATA32_REG_BM, NJATA32_BM_WAIT0);
    287 }
    288 
    289 static void
    290 njata32_clearirq(chp, irq)
    291 	struct ata_channel *chp;
    292 	int irq;
    293 {
    294 	struct njata32_softc *sc = (void *)chp->ch_atac;
    295 
    296 	printf("%s: unhandled intr: irq %#x, bm %#x, ",
    297 	    NJATA32NAME(sc), irq,
    298 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    299 		NJATA32_REG_BM));
    300 
    301 	/* disable busmaster */
    302 	njata32_irqack(chp);
    303 
    304 	/* clear device interrupt */
    305 	printf("err %#x, seccnt %#x, cyl %#x, sdh %#x, ",
    306 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    307 		NJATA32_REG_WD_ERROR),
    308 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    309 		NJATA32_REG_WD_SECCNT),
    310 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    311 		NJATA32_REG_WD_CYL_LO) |
    312 	    (bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    313 		NJATA32_REG_WD_CYL_HI) << 8),
    314 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    315 		NJATA32_REG_WD_SDH));
    316 	printf("status %#x\n",
    317 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    318 	    NJATA32_REG_WD_STATUS));
    319 }
    320 
    321 static void
    322 njata32_setup_channel(chp)
    323 	struct ata_channel *chp;
    324 {
    325 	struct njata32_softc *sc = (void *)chp->ch_atac;
    326 	struct ata_drive_datas *drvp;
    327 	int drive;
    328 	uint8_t mode;
    329 
    330 	KASSERT(chp->ch_ndrive != 0);
    331 
    332 	sc->sc_timing_pio = 0;
    333 #if 0	/* ATA DMA is currently unused */
    334 	sc->sc_timing_dma = 0;
    335 #endif
    336 
    337 	for (drive = 0; drive < chp->ch_ndrive; drive++) {
    338 		drvp = &chp->ch_drive[drive];
    339 		if ((drvp->drive_flags & DRIVE) == 0)
    340 			continue;	/* no drive */
    341 
    342 #if 0	/* ATA DMA is currently unused */
    343 		if ((drvp->drive_flags & DRIVE_DMA) != 0) {
    344 			/*
    345 			 * Multiword DMA
    346 			 */
    347 			if ((mode = drvp->DMA_mode) > NJATA32_MODE_MAX_DMA)
    348 				mode = NJATA32_MODE_MAX_DMA;
    349 			if (sc->sc_timing_dma < njata32_timing_dma[mode])
    350 				sc->sc_timing_dma = njata32_timing_dma[mode];
    351 		}
    352 #endif
    353 		/*
    354 		 * PIO
    355 		 */
    356 		if ((mode = drvp->PIO_mode) > NJATA32_MODE_MAX_PIO)
    357 			mode = NJATA32_MODE_MAX_PIO;
    358 		if (sc->sc_timing_pio < njata32_timing_pio[mode])
    359 			sc->sc_timing_pio = njata32_timing_pio[mode];
    360 	}
    361 
    362 	sc->sc_timing_pio += sc->sc_atawait;
    363 
    364 	/* set timing for PIO */
    365 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    366 	    NJATA32_REG_TIMING, sc->sc_timing_pio);
    367 }
    368 
    369 /*
    370  * map DMA buffer
    371  */
    372 int
    373 njata32_dma_init(v, channel, drive, databuf, datalen, flags)
    374 	void *v;
    375 	int channel, drive;
    376 	void *databuf;
    377 	size_t datalen;
    378 	int flags;
    379 {
    380 	struct njata32_softc *sc = v;
    381 	int error;
    382 	struct njata32_device *dev = &sc->sc_dev[drive];
    383 
    384 	KASSERT(channel == 0);
    385 	KASSERT((dev->d_flags & NJATA32_DEV_DMA_MAPPED) == 0);
    386 	KASSERT((dev->d_flags & NJATA32_DEV_DMA_STARTED) == 0);
    387 
    388 	KASSERT(flags & (WDC_DMA_PIOBM_ATA | WDC_DMA_PIOBM_ATAPI));
    389 
    390 	/* use PIO for short transfer */
    391 	if (datalen < 64 /* needs tune */) {
    392 		DPRINTF(("%s: njata32_dma_init: short transfer (%u)\n",
    393 		    NJATA32NAME(sc), (unsigned)datalen));
    394 		bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    395 		    NJATA32_REG_TIMING, sc->sc_timing_pio);
    396 		return EINVAL;
    397 	}
    398 
    399 	/* use PIO for unaligned transfer (word alignment seems OK) */
    400 	if (((uintptr_t)databuf & 1) || (datalen & 1)) {
    401 		DPRINTF(("%s: njata32_dma_init: unaligned: buf %p, len %u\n",
    402 		    NJATA32NAME(sc), databuf, (unsigned)datalen));
    403 		return EINVAL;
    404 	}
    405 
    406 	DPRINTF(("%s: njata32_dma_init: %s: databuf %p, datalen %u\n",
    407 	    NJATA32NAME(sc), (flags & WDC_DMA_READ) ? "read" : "write",
    408 	    databuf, (unsigned)datalen));
    409 
    410 	error = bus_dmamap_load(sc->sc_dmat, dev->d_dmamap_xfer,
    411 	    databuf, datalen, NULL, BUS_DMA_NOWAIT | BUS_DMA_STREAMING |
    412 	    ((flags & WDC_DMA_READ) ? BUS_DMA_READ : BUS_DMA_WRITE));
    413 	if (error) {
    414 		printf("%s: load xfer failed, error %d\n",
    415 		    NJATA32NAME(sc), error);
    416 		return error;
    417 	}
    418 
    419 	bus_dmamap_sync(sc->sc_dmat, dev->d_dmamap_xfer, 0,
    420 	    dev->d_dmamap_xfer->dm_mapsize,
    421 	    (flags & WDC_DMA_READ) ?
    422 		BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
    423 
    424 	dev->d_flags =
    425 	    ((flags & WDC_DMA_READ) ? NJATA32_DEV_DMA_READ : 0) |
    426 	    ((flags & WDC_DMA_PIOBM_ATAPI) ? NJATA32_DEV_DMA_ATAPI : 0) |
    427 	    NJATA32_DEV_DMA_MAPPED;
    428 
    429 	return 0;
    430 }
    431 
    432 /*
    433  * start DMA
    434  *
    435  * top:  databuf + skip
    436  * size: xferlen
    437  */
    438 void
    439 njata32_piobm_start(v, channel, drive, skip, xferlen, flags)
    440 	void *v;
    441 	int channel, drive;
    442 	int skip, xferlen;	/* offset/size in mapped DMA buffer */
    443 	int flags;
    444 {
    445 	struct njata32_softc *sc = v;
    446 	struct njata32_device *dev = &sc->sc_dev[drive];
    447 	int i, nsegs, seglen;
    448 	uint8_t bmreg;
    449 
    450 	DPRINTF(("%s: njata32_piobm_start: ch%d, dv%d, skip %d, xferlen %d\n",
    451 	    NJATA32NAME(sc), channel, drive, skip, xferlen));
    452 
    453 	KASSERT(channel == 0);
    454 	KASSERT(dev->d_flags & NJATA32_DEV_DMA_MAPPED);
    455 	KASSERT((dev->d_flags & NJATA32_DEV_DMA_STARTED) == 0);
    456 
    457 	/*
    458 	 * create scatter/gather table
    459 	 * XXX this code may be slow
    460 	 */
    461 	for (i = nsegs = 0;
    462 	    i < dev->d_dmamap_xfer->dm_nsegs && xferlen > 0; i++) {
    463 		if (dev->d_dmamap_xfer->dm_segs[i].ds_len <= skip) {
    464 			skip -= dev->d_dmamap_xfer->dm_segs[i].ds_len;
    465 			continue;
    466 		}
    467 
    468 		seglen = dev->d_dmamap_xfer->dm_segs[i].ds_len - skip;
    469 		if (seglen > xferlen)
    470 			seglen = xferlen;
    471 
    472 		dev->d_sgt[nsegs].sg_addr =
    473 		    htole32(dev->d_dmamap_xfer->dm_segs[i].ds_addr + skip);
    474 		dev->d_sgt[nsegs].sg_len = htole32(seglen);
    475 
    476 		xferlen -= seglen;
    477 		nsegs++;
    478 		skip = 0;
    479 	}
    480 	sc->sc_piobm_nsegs = nsegs;
    481 	/* end mark */
    482 	dev->d_sgt[nsegs - 1].sg_len |= htole32(NJATA32_SGT_ENDMARK);
    483 
    484 #ifdef DIAGNOSTIC
    485 	if (xferlen)
    486 		panic("%s: njata32_piobm_start: xferlen residue %d\n",
    487 		    NJATA32NAME(sc), xferlen);
    488 #endif
    489 
    490 	bus_dmamap_sync(sc->sc_dmat, sc->sc_dmamap_sgt,
    491 	    (char *)dev->d_sgt - (char *)sc->sc_sgtpg,
    492 	    sizeof(struct njata32_sgtable) * nsegs,
    493 	    BUS_DMASYNC_PREWRITE);
    494 
    495 	/* set timing for PIO */
    496 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    497 	    NJATA32_REG_TIMING, sc->sc_timing_pio);
    498 
    499 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_IOBM,
    500 	    NJATA32_IOBM_DEFAULT);
    501 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_AS,
    502 	    NJATA32_AS_WAIT0);
    503 
    504 	/*
    505 	 * interrupt configuration
    506 	 */
    507 	if ((dev->d_flags & (NJATA32_DEV_DMA_READ | NJATA32_DEV_DMA_ATAPI)) ==
    508 	    NJATA32_DEV_DMA_READ) {
    509 		/*
    510 		 * ATA piobm read is executed while device interrupt is active,
    511 		 * so disable device interrupt here
    512 		 */
    513 		bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    514 		    NJATA32_REG_IRQ_SELECT, NJATA32_IRQ_XFER);
    515 	}
    516 
    517 	/* enable scatter/gather busmaster transfer */
    518 	bmreg = NJATA32_BM_EN | NJATA32_BM_SG | NJATA32_BM_WAIT0 |
    519 	    ((dev->d_flags & NJATA32_DEV_DMA_READ) ? NJATA32_BM_RD : 0);
    520 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_BM,
    521 	    bmreg);
    522 
    523 	/* load scatter/gather table */
    524 	bus_space_write_4(NJATA32_REGT(sc), NJATA32_REGH(sc),
    525 	    NJATA32_REG_DMAADDR, dev->d_sgt_dma);
    526 	bus_space_write_4(NJATA32_REGT(sc), NJATA32_REGH(sc),
    527 	    NJATA32_REG_DMALENGTH, sizeof(struct njata32_sgtable) * nsegs);
    528 
    529 	/* start transfer */
    530 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_BM,
    531 	    (bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    532 		NJATA32_REG_BM)
    533 	     & ~(NJATA32_BM_RD|NJATA32_BM_SG|NJATA32_BM_WAIT_MASK)) |
    534 	    bmreg | NJATA32_BM_GO);
    535 
    536 	sc->sc_devflags = dev->d_flags;
    537 	if (flags & WDC_PIOBM_XFER_IRQ)
    538 		sc->sc_devflags |= NJATA32_DEV_XFER_INTR;
    539 #ifdef DIAGNOSTIC
    540 	dev->d_flags |= NJATA32_DEV_DMA_STARTED;
    541 #endif
    542 }
    543 
    544 /*
    545  * end of DMA
    546  */
    547 int
    548 njata32_dma_finish(v, channel, drive, force)
    549 	void *v;
    550 	int channel, drive;
    551 	int force;
    552 {
    553 	struct njata32_softc *sc = v;
    554 	int bm;
    555 	int error = 0;
    556 
    557 	DPRINTF(("%s: njata32_dma_finish: bm = %#x\n", NJATA32NAME(sc),
    558 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    559 		NJATA32_REG_BM)));
    560 
    561 	KASSERT(channel == 0);
    562 	KASSERT(sc->sc_dev[drive].d_flags & NJATA32_DEV_DMA_MAPPED);
    563 	KASSERT(sc->sc_dev[drive].d_flags & NJATA32_DEV_DMA_STARTED);
    564 
    565 	bm = bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    566 	    NJATA32_REG_BM);
    567 
    568 #ifdef NJATA32_DEBUG
    569 	printf("%s: irq %#x, bm %#x, 18 %#x, 1c %#x\n", NJATA32NAME(sc),
    570 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    571 		NJATA32_REG_IRQ_STAT),
    572 	    bm,
    573 	    bus_space_read_4(NJATA32_REGT(sc), NJATA32_REGH(sc), 0x18),
    574 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc), 0x1c));
    575 #endif
    576 
    577 	/* check if DMA is active */
    578 	if (bm & NJATA32_BM_GO) {
    579 		error = WDC_DMAST_NOIRQ;
    580 
    581 		switch (force) {
    582 		case WDC_DMAEND_END:
    583 			return error;
    584 
    585 		case WDC_DMAEND_ABRT:
    586 			printf("%s: aborting DMA\n", NJATA32NAME(sc));
    587 			break;
    588 		}
    589 	}
    590 
    591 	/*
    592 	 * ???
    593 	 * For unknown reason, PIOBM transfer sometimes fails in the middle,
    594 	 * in which case the bit #7 of BM register becomes 0.
    595 	 * Increasing the wait value seems to improve the situation.
    596 	 *
    597 	 * XXX
    598 	 * PIO transfer may also fail, but it seems it can't be detected.
    599 	 */
    600 	if ((bm & NJATA32_BM_DONE) == 0) {
    601 		error |= WDC_DMAST_ERR;
    602 		printf("%s: busmaster error", NJATA32NAME(sc));
    603 		if (sc->sc_atawait < 0x11) {
    604 			if ((sc->sc_atawait & 0xf) == 0)
    605 				sc->sc_atawait++;
    606 			else
    607 				sc->sc_atawait += 0x10;
    608 			printf(", new ATA wait = %#x", sc->sc_atawait);
    609 			njata32_setup_channel(&sc->sc_ch[0].ch_ata_channel);
    610 		}
    611 		printf("\n");
    612 	}
    613 
    614 	/* stop command */
    615 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_AS,
    616 	    NJATA32_AS_WAIT0);
    617 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc), NJATA32_REG_BM,
    618 	    NJATA32_BM_WAIT0);
    619 
    620 	/* set timing for PIO */
    621 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    622 	    NJATA32_REG_TIMING, sc->sc_timing_pio);
    623 
    624 	/*
    625 	 * reenable device interrupt in case it was disabled for
    626 	 * this transfer
    627 	 */
    628 	bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    629 	    NJATA32_REG_IRQ_SELECT, NJATA32_IRQ_XFER | NJATA32_IRQ_DEV);
    630 
    631 #if 1	/* should be? */
    632 	if ((sc->sc_devflags & NJATA32_DEV_GOT_XFER_INTR) == 0)
    633 		error |= WDC_DMAST_ERR;
    634 #endif
    635 	sc->sc_devflags = 0;
    636 
    637 #ifdef DIAGNOSTIC
    638 	sc->sc_dev[drive].d_flags &= ~NJATA32_DEV_DMA_STARTED;
    639 #endif
    640 
    641 	return error;
    642 }
    643 
    644 /*
    645  * unmap DMA buffer
    646  */
    647 void
    648 njata32_piobm_done(v, channel, drive)
    649 	void *v;
    650 	int channel, drive;
    651 {
    652 	struct njata32_softc *sc = v;
    653 	struct njata32_device *dev = &sc->sc_dev[drive];
    654 
    655 	DPRINTF(("%s: njata32_piobm_done: ch%d dv%d\n",
    656 	    NJATA32NAME(sc), channel, drive));
    657 
    658 	KASSERT(channel == 0);
    659 	KASSERT(dev->d_flags & NJATA32_DEV_DMA_MAPPED);
    660 	KASSERT((dev->d_flags & NJATA32_DEV_DMA_STARTED) == 0);
    661 
    662 	bus_dmamap_sync(sc->sc_dmat, sc->sc_dmamap_sgt,
    663 	    (char *)dev->d_sgt - (char *)sc->sc_sgtpg,
    664 	    sizeof(struct njata32_sgtable) * sc->sc_piobm_nsegs,
    665 	    BUS_DMASYNC_POSTWRITE);
    666 
    667 	/* unload dma map */
    668 	bus_dmamap_sync(sc->sc_dmat, dev->d_dmamap_xfer,
    669 	    0, dev->d_dmamap_xfer->dm_mapsize,
    670 	    (dev->d_flags & NJATA32_DEV_DMA_READ) ?
    671 		BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
    672 
    673 	bus_dmamap_sync(sc->sc_dmat, sc->sc_dmamap_sgt,
    674 	    (char *)dev->d_sgt - (char *)sc->sc_sgtpg,
    675 	    sizeof(struct njata32_sgtable) * NJATA32_NUM_SG,
    676 	    BUS_DMASYNC_POSTWRITE);
    677 
    678 	bus_dmamap_unload(sc->sc_dmat, dev->d_dmamap_xfer);
    679 	dev->d_flags &= ~NJATA32_DEV_DMA_MAPPED;
    680 }
    681 
    682 int
    683 njata32_intr(arg)
    684 	void *arg;
    685 {
    686 	struct njata32_softc *sc = arg;
    687 	struct ata_channel *chp;
    688 	int irq;
    689 
    690 	irq = bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    691 	    NJATA32_REG_IRQ_STAT);
    692 	if ((irq & (NJATA32_IRQ_XFER | NJATA32_IRQ_DEV)) == 0)
    693 		return 0;	/* not mine */
    694 
    695 	DPRINTF(("%s: njata32_intr: irq = %#x, altstatus = %#x\n",
    696 	    NJATA32NAME(sc), irq,
    697 	    bus_space_read_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    698 		NJATA32_REG_WD_ALTSTATUS)));
    699 
    700 	chp = &sc->sc_ch[0].ch_ata_channel;
    701 
    702 	if (irq & NJATA32_IRQ_XFER)
    703 		sc->sc_devflags |= NJATA32_DEV_GOT_XFER_INTR;
    704 
    705 	if ((irq & (NJATA32_IRQ_XFER | NJATA32_IRQ_DEV)) == NJATA32_IRQ_XFER &&
    706 	    (sc->sc_devflags & NJATA32_DEV_XFER_INTR) == 0) {
    707 		/*
    708 		 * transfer done, wait for device interrupt
    709 		 */
    710 		bus_space_write_1(NJATA32_REGT(sc), NJATA32_REGH(sc),
    711 		    NJATA32_REG_BM, NJATA32_BM_WAIT0);
    712 		return 1;
    713 	}
    714 
    715 	/*
    716 	 * If both transfer done interrupt and device interrupt are
    717 	 * active for ATAPI transfer, call wdcintr() twice.
    718 	 */
    719 	if ((sc->sc_devflags & NJATA32_DEV_DMA_ATAPI) &&
    720 	    (irq & (NJATA32_IRQ_XFER | NJATA32_IRQ_DEV)) ==
    721 		(NJATA32_IRQ_XFER | NJATA32_IRQ_DEV) &&
    722 	    (sc->sc_devflags & NJATA32_DEV_XFER_INTR)) {
    723 		if (wdcintr(chp) == 0) {
    724 			njata32_clearirq(&sc->sc_ch[0].ch_ata_channel, irq);
    725 		}
    726 	}
    727 
    728 	if (wdcintr(chp) == 0) {
    729 		njata32_clearirq(&sc->sc_ch[0].ch_ata_channel, irq);
    730 	}
    731 
    732 	return 1;
    733 }
    734