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wdc_obio.c revision 1.49
      1 /*	$NetBSD: wdc_obio.c,v 1.49 2008/03/18 20:46:36 cube Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1998, 2003 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Charles M. Hannum and by Onno van der Linden.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *        This product includes software developed by the NetBSD
     21  *        Foundation, Inc. and its contributors.
     22  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  *    contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  * POSSIBILITY OF SUCH DAMAGE.
     37  */
     38 
     39 #include <sys/cdefs.h>
     40 __KERNEL_RCSID(0, "$NetBSD: wdc_obio.c,v 1.49 2008/03/18 20:46:36 cube Exp $");
     41 
     42 #include <sys/param.h>
     43 #include <sys/systm.h>
     44 #include <sys/device.h>
     45 #include <sys/malloc.h>
     46 
     47 #include <uvm/uvm_extern.h>
     48 
     49 #include <machine/bus.h>
     50 #include <machine/autoconf.h>
     51 #include <machine/pio.h>
     52 
     53 #include <dev/ata/atareg.h>
     54 #include <dev/ata/atavar.h>
     55 #include <dev/ic/wdcvar.h>
     56 
     57 #include <dev/ofw/openfirm.h>
     58 
     59 #include <macppc/dev/dbdma.h>
     60 
     61 #define WDC_REG_NPORTS		8
     62 #define WDC_AUXREG_OFFSET	0x16
     63 #define WDC_DEFAULT_PIO_IRQ	13	/* XXX */
     64 #define WDC_DEFAULT_DMA_IRQ	2	/* XXX */
     65 
     66 #define WDC_OPTIONS_DMA 0x01
     67 
     68 /*
     69  * XXX This code currently doesn't even try to allow 32-bit data port use.
     70  */
     71 
     72 struct wdc_obio_softc {
     73 	struct wdc_softc sc_wdcdev;
     74 	struct ata_channel *sc_chanptr;
     75 	struct ata_channel sc_channel;
     76 	struct ata_queue sc_chqueue;
     77 	struct wdc_regs sc_wdc_regs;
     78 	bus_space_handle_t sc_dmaregh;
     79 	dbdma_regmap_t *sc_dmareg;
     80 	dbdma_command_t	*sc_dmacmd;
     81 	u_int sc_dmaconf[2];	/* per target value of CONFIG_REG */
     82 	void *sc_ih;
     83 };
     84 
     85 static int wdc_obio_match(device_t, cfdata_t, void *);
     86 static void wdc_obio_attach(device_t, device_t, void *);
     87 static int wdc_obio_detach(device_t, int);
     88 static int wdc_obio_dma_init(void *, int, int, void *, size_t, int);
     89 static void wdc_obio_dma_start(void *, int, int);
     90 static int wdc_obio_dma_finish(void *, int, int, int);
     91 
     92 static void wdc_obio_select(struct ata_channel *, int);
     93 static void adjust_timing(struct ata_channel *);
     94 static void ata4_adjust_timing(struct ata_channel *);
     95 
     96 CFATTACH_DECL_NEW(wdc_obio, sizeof(struct wdc_obio_softc),
     97     wdc_obio_match, wdc_obio_attach, wdc_obio_detach, wdcactivate);
     98 
     99 static const char * const ata_names[] = {
    100     "heathrow-ata",
    101     "keylargo-ata",
    102     "ohare-ata",
    103     NULL
    104 };
    105 
    106 int
    107 wdc_obio_match(device_t parent, cfdata_t match, void *aux)
    108 {
    109 	struct confargs *ca = aux;
    110 
    111 	/* XXX should not use name */
    112 	if (strcmp(ca->ca_name, "ATA") == 0 ||
    113 	    strcmp(ca->ca_name, "ata") == 0 ||
    114 	    strcmp(ca->ca_name, "ata0") == 0 ||
    115 	    strcmp(ca->ca_name, "ide") == 0)
    116 		return 1;
    117 
    118 	if (of_compatible(ca->ca_node, ata_names) >= 0)
    119 		return 1;
    120 
    121 	return 0;
    122 }
    123 
    124 void
    125 wdc_obio_attach(device_t parent, device_t self, void *aux)
    126 {
    127 	struct wdc_obio_softc *sc = device_private(self);
    128 	struct wdc_regs *wdr;
    129 	struct confargs *ca = aux;
    130 	struct ata_channel *chp = &sc->sc_channel;
    131 	int intr, i, type = IST_EDGE;
    132 	int use_dma = 0;
    133 	char path[80];
    134 
    135 	sc->sc_wdcdev.sc_atac.atac_dev = self;
    136 	if (device_cfdata(sc->sc_wdcdev.sc_atac.atac_dev)->cf_flags &
    137 	    WDC_OPTIONS_DMA) {
    138 		if (ca->ca_nreg >= 16 || ca->ca_nintr == -1)
    139 			use_dma = 1;	/* XXX Don't work yet. */
    140 	}
    141 
    142 	if (ca->ca_nintr >= 4 && ca->ca_nreg >= 8) {
    143 		intr = ca->ca_intr[0];
    144 		aprint_normal(" irq %d", intr);
    145 		if (ca->ca_nintr > 8) {
    146 			type = ca->ca_intr[1] ? IST_LEVEL : IST_EDGE;
    147 		}
    148 		aprint_normal(", %s triggered", (type == IST_EDGE) ? "edge" : "level");
    149 	} else if (ca->ca_nintr == -1) {
    150 		intr = WDC_DEFAULT_PIO_IRQ;
    151 		aprint_normal(" irq property not found; using %d", intr);
    152 	} else {
    153 		aprint_error(": couldn't get irq property\n");
    154 		return;
    155 	}
    156 
    157 	if (use_dma)
    158 		aprint_normal(": DMA transfer");
    159 
    160 	aprint_normal("\n");
    161 
    162 	sc->sc_wdcdev.regs = wdr = &sc->sc_wdc_regs;
    163 
    164 	wdr->cmd_iot = wdr->ctl_iot = ca->ca_tag;
    165 
    166 	if (bus_space_map(wdr->cmd_iot, ca->ca_baseaddr + ca->ca_reg[0],
    167 	    WDC_REG_NPORTS << 4, 0, &wdr->cmd_baseioh) ||
    168 	    bus_space_subregion(wdr->cmd_iot, wdr->cmd_baseioh,
    169 			WDC_AUXREG_OFFSET << 4, 1, &wdr->ctl_ioh)) {
    170 		aprint_error_dev(self, "couldn't map registers\n");
    171 		return;
    172 	}
    173 
    174 	for (i = 0; i < WDC_NREG; i++) {
    175 		if (bus_space_subregion(wdr->cmd_iot, wdr->cmd_baseioh, i << 4,
    176 		    i == 0 ? 4 : 1, &wdr->cmd_iohs[i]) != 0) {
    177 			bus_space_unmap(wdr->cmd_iot, wdr->cmd_baseioh,
    178 			    WDC_REG_NPORTS << 4);
    179 			aprint_error_dev(self,
    180 			    "couldn't subregion registers\n");
    181 			return;
    182 		}
    183 	}
    184 #if 0
    185 	wdr->data32iot = wdr->cmd_iot;
    186 	wdr->data32ioh = wdr->cmd_ioh;
    187 #endif
    188 
    189 	sc->sc_ih = intr_establish(intr, type, IPL_BIO, wdcintr, chp);
    190 
    191 	if (use_dma) {
    192 		sc->sc_dmacmd = dbdma_alloc(sizeof(dbdma_command_t) * 20);
    193 		/*
    194 		 * XXX
    195 		 * we don't use ca->ca_reg[3] for size here because at least
    196 		 * on the PB3400c it says 0x200 for both IDE channels ( the
    197 		 * one on the mainboard and the other on the mediabay ) but
    198 		 * their start addresses are only 0x100 apart. Since those
    199 		 * DMA registers are always 0x100 or less we don't really
    200 		 * have to care though
    201 		 */
    202 		if (bus_space_map(wdr->cmd_iot, ca->ca_baseaddr + ca->ca_reg[2],
    203 		    0x100, BUS_SPACE_MAP_LINEAR, &sc->sc_dmaregh)) {
    204 
    205 			aprint_error_dev(self,
    206 			    "unable to map DMA registers (%08x)\n",
    207 			    ca->ca_reg[2]);
    208 			/* should unmap stuff here */
    209 			return;
    210 		}
    211 		sc->sc_dmareg = bus_space_vaddr(wdr->cmd_iot, sc->sc_dmaregh);
    212 
    213 		sc->sc_wdcdev.sc_atac.atac_cap |= ATAC_CAP_DMA;
    214 		sc->sc_wdcdev.sc_atac.atac_dma_cap = 2;
    215 		if (strcmp(ca->ca_name, "ata-4") == 0) {
    216 			sc->sc_wdcdev.sc_atac.atac_cap |= ATAC_CAP_UDMA;
    217 			sc->sc_wdcdev.sc_atac.atac_udma_cap = 4;
    218 			sc->sc_wdcdev.sc_atac.atac_set_modes =
    219 			    ata4_adjust_timing;
    220 		} else {
    221 			sc->sc_wdcdev.sc_atac.atac_set_modes = adjust_timing;
    222 		}
    223 #ifdef notyet
    224 		/* Minimum cycle time is 150ns (DMA MODE 1) on ohare. */
    225 		if (ohare) {
    226 			sc->sc_wdcdev.sc_atac.atac_pio_cap = 3;
    227 			sc->sc_wdcdev.sc_atac.atac_dma_cap = 1;
    228 		}
    229 #endif
    230 	} else {
    231 		/* all non-DMA controllers can use adjust_timing */
    232 		sc->sc_wdcdev.sc_atac.atac_set_modes = adjust_timing;
    233 	}
    234 
    235 	sc->sc_wdcdev.sc_atac.atac_pio_cap = 4;
    236 	sc->sc_wdcdev.sc_atac.atac_cap |= ATAC_CAP_DATA16;
    237 	sc->sc_chanptr = chp;
    238 	sc->sc_wdcdev.sc_atac.atac_channels = &sc->sc_chanptr;
    239 	sc->sc_wdcdev.sc_atac.atac_nchannels = 1;
    240 	sc->sc_wdcdev.dma_arg = sc;
    241 	sc->sc_wdcdev.dma_init = wdc_obio_dma_init;
    242 	sc->sc_wdcdev.dma_start = wdc_obio_dma_start;
    243 	sc->sc_wdcdev.dma_finish = wdc_obio_dma_finish;
    244 	chp->ch_channel = 0;
    245 	chp->ch_atac = &sc->sc_wdcdev.sc_atac;
    246 	chp->ch_queue = &sc->sc_chqueue;
    247 	chp->ch_ndrive = 2;
    248 
    249 	wdc_init_shadow_regs(chp);
    250 
    251 #define OHARE_FEATURE_REG	0xf3000038
    252 
    253 	/* XXX Enable wdc1 by feature reg. */
    254 	memset(path, 0, sizeof(path));
    255 	OF_package_to_path(ca->ca_node, path, sizeof(path));
    256 	if (strcmp(path, "/bandit@F2000000/ohare@10/ata@21000") == 0) {
    257 		u_int x;
    258 
    259 		x = in32rb(OHARE_FEATURE_REG);
    260 		x |= 8;
    261 		out32rb(OHARE_FEATURE_REG, x);
    262 	}
    263 
    264 	wdcattach(chp);
    265 }
    266 
    267 /* Multiword DMA transfer timings */
    268 struct ide_timings {
    269 	int cycle;	/* minimum cycle time [ns] */
    270 	int active;	/* minimum command active time [ns] */
    271 };
    272 static const struct ide_timings pio_timing[5] = {
    273 	{ 600, 180 },    /* Mode 0 */
    274 	{ 390, 150 },    /*      1 */
    275 	{ 240, 105 },    /*      2 */
    276 	{ 180,  90 },    /*      3 */
    277 	{ 120,  75 }     /*      4 */
    278 };
    279 static const struct ide_timings dma_timing[3] = {
    280 	{ 480, 240 },	/* Mode 0 */
    281 	{ 165,  90 },	/* Mode 1 */
    282 	{ 120,  75 }	/* Mode 2 */
    283 };
    284 
    285 static const struct ide_timings udma_timing[5] = {
    286 	{ 120, 180 },	/* Mode 0 */
    287 	{  90, 150 },	/* Mode 1 */
    288 	{  60, 120 },	/* Mode 2 */
    289 	{  45,  90 },	/* Mode 3 */
    290 	{  30,  90 }	/* Mode 4 */
    291 };
    292 
    293 #define TIME_TO_TICK(time) howmany((time), 30)
    294 #define PIO_REC_OFFSET 4
    295 #define PIO_REC_MIN 1
    296 #define PIO_ACT_MIN 1
    297 #define DMA_REC_OFFSET 1
    298 #define DMA_REC_MIN 1
    299 #define DMA_ACT_MIN 1
    300 
    301 #define ATA4_TIME_TO_TICK(time)  howmany((time), 15) /* 15 ns clock */
    302 
    303 #define CONFIG_REG (0x200)		/* IDE access timing register */
    304 
    305 void
    306 wdc_obio_select(struct ata_channel *chp, int drive)
    307 {
    308 	struct wdc_obio_softc *sc = (struct wdc_obio_softc *)chp->ch_atac;
    309 	struct wdc_regs *wdr = CHAN_TO_WDC_REGS(chp);
    310 
    311 	bus_space_write_4(wdr->cmd_iot, wdr->cmd_baseioh,
    312 			CONFIG_REG, sc->sc_dmaconf[drive]);
    313 }
    314 
    315 void
    316 adjust_timing(struct ata_channel *chp)
    317 {
    318 	struct wdc_obio_softc *sc = (struct wdc_obio_softc *)chp->ch_atac;
    319 	int drive;
    320 	int min_cycle = 0, min_active = 0;
    321 	int cycle_tick = 0, act_tick = 0, inact_tick = 0, half_tick;
    322 
    323 	for (drive = 0; drive < 2; drive++) {
    324 		u_int conf = 0;
    325 		struct ata_drive_datas *drvp;
    326 
    327 		drvp = &chp->ch_drive[drive];
    328 		/* set up pio mode timings */
    329 		if (drvp->drive_flags & DRIVE) {
    330 			int piomode = drvp->PIO_mode;
    331 			min_cycle = pio_timing[piomode].cycle;
    332 			min_active = pio_timing[piomode].active;
    333 
    334 			cycle_tick = TIME_TO_TICK(min_cycle);
    335 			act_tick = TIME_TO_TICK(min_active);
    336 			if (act_tick < PIO_ACT_MIN)
    337 				act_tick = PIO_ACT_MIN;
    338 			inact_tick = cycle_tick - act_tick - PIO_REC_OFFSET;
    339 			if (inact_tick < PIO_REC_MIN)
    340 				inact_tick = PIO_REC_MIN;
    341 			/* mask: 0x000007ff */
    342 			conf |= (inact_tick << 5) | act_tick;
    343 		}
    344 		/* Set up DMA mode timings */
    345 		if (drvp->drive_flags & DRIVE_DMA) {
    346 			int dmamode = drvp->DMA_mode;
    347 			min_cycle = dma_timing[dmamode].cycle;
    348 			min_active = dma_timing[dmamode].active;
    349 			cycle_tick = TIME_TO_TICK(min_cycle);
    350 			act_tick = TIME_TO_TICK(min_active);
    351 			inact_tick = cycle_tick - act_tick - DMA_REC_OFFSET;
    352 			if (inact_tick < DMA_REC_MIN)
    353 				inact_tick = DMA_REC_MIN;
    354 			half_tick = 0;	/* XXX */
    355 			/* mask: 0xfffff800 */
    356 			conf |=
    357 					(half_tick << 21) |
    358 					(inact_tick << 16) | (act_tick << 11);
    359 		}
    360 #ifdef DEBUG
    361 		if (conf) {
    362 			printf("conf[%d] = 0x%x, cyc = %d (%d ns), act = %d (%d ns), inact = %d\n",
    363 					drive, conf, cycle_tick, min_cycle, act_tick, min_active, inact_tick);
    364 		}
    365 #endif
    366 		sc->sc_dmaconf[drive] = conf;
    367 	}
    368 	sc->sc_wdcdev.select = 0;
    369 	if (sc->sc_dmaconf[0]) {
    370 		wdc_obio_select(chp,0);
    371 		if (sc->sc_dmaconf[1] &&
    372 		    (sc->sc_dmaconf[0] != sc->sc_dmaconf[1])) {
    373 			sc->sc_wdcdev.select = wdc_obio_select;
    374 		}
    375 	} else if (sc->sc_dmaconf[1]) {
    376 		wdc_obio_select(chp,1);
    377 	}
    378 }
    379 
    380 void
    381 ata4_adjust_timing(struct ata_channel *chp)
    382 {
    383 	struct wdc_obio_softc *sc = (struct wdc_obio_softc *)chp->ch_atac;
    384 	int drive;
    385 	int min_cycle = 0, min_active = 0;
    386 	int cycle_tick = 0, act_tick = 0, inact_tick = 0;
    387 
    388 	for (drive = 0; drive < 2; drive++) {
    389 		u_int conf = 0;
    390 		struct ata_drive_datas *drvp;
    391 
    392 		drvp = &chp->ch_drive[drive];
    393 		/* set up pio mode timings */
    394 
    395 		if (drvp->drive_flags & DRIVE) {
    396 			int piomode = drvp->PIO_mode;
    397 			min_cycle = pio_timing[piomode].cycle;
    398 			min_active = pio_timing[piomode].active;
    399 
    400 			cycle_tick = ATA4_TIME_TO_TICK(min_cycle);
    401 			act_tick = ATA4_TIME_TO_TICK(min_active);
    402 			inact_tick = cycle_tick - act_tick;
    403 			/* mask: 0x000003ff */
    404 			conf |= (inact_tick << 5) | act_tick;
    405 		}
    406 		/* set up dma mode timings */
    407 		if (drvp->drive_flags & DRIVE_DMA) {
    408 			int dmamode = drvp->DMA_mode;
    409 			min_cycle = dma_timing[dmamode].cycle;
    410 			min_active = dma_timing[dmamode].active;
    411 			cycle_tick = ATA4_TIME_TO_TICK(min_cycle);
    412 			act_tick = ATA4_TIME_TO_TICK(min_active);
    413 			inact_tick = cycle_tick - act_tick;
    414 			/* mask: 0x001ffc00 */
    415 			conf |= (act_tick << 10) | (inact_tick << 15);
    416 		}
    417 		/* set up udma mode timings */
    418 		if (drvp->drive_flags & DRIVE_UDMA) {
    419 			int udmamode = drvp->UDMA_mode;
    420 			min_cycle = udma_timing[udmamode].cycle;
    421 			min_active = udma_timing[udmamode].active;
    422 			act_tick = ATA4_TIME_TO_TICK(min_active);
    423 			cycle_tick = ATA4_TIME_TO_TICK(min_cycle);
    424 			/* mask: 0x1ff00000 */
    425 			conf |= (cycle_tick << 21) | (act_tick << 25) | 0x100000;
    426 		}
    427 #ifdef DEBUG
    428 		if (conf) {
    429 			printf("ata4 conf[%d] = 0x%x, cyc = %d (%d ns), act = %d (%d ns), inact = %d\n",
    430 					drive, conf, cycle_tick, min_cycle, act_tick, min_active, inact_tick);
    431 		}
    432 #endif
    433 		sc->sc_dmaconf[drive] = conf;
    434 	}
    435 	sc->sc_wdcdev.select = 0;
    436 	if (sc->sc_dmaconf[0]) {
    437 		wdc_obio_select(chp,0);
    438 		if (sc->sc_dmaconf[1] &&
    439 		    (sc->sc_dmaconf[0] != sc->sc_dmaconf[1])) {
    440 			sc->sc_wdcdev.select = wdc_obio_select;
    441 		}
    442 	} else if (sc->sc_dmaconf[1]) {
    443 		wdc_obio_select(chp,1);
    444 	}
    445 }
    446 
    447 int
    448 wdc_obio_detach(device_t self, int flags)
    449 {
    450 	struct wdc_obio_softc *sc = device_private(self);
    451 	int error;
    452 
    453 	if ((error = wdcdetach(self, flags)) != 0)
    454 		return error;
    455 
    456 	intr_disestablish(sc->sc_ih);
    457 
    458 	/* Unmap our i/o space. */
    459 	bus_space_unmap(sc->sc_wdcdev.regs->cmd_iot,
    460 			sc->sc_wdcdev.regs->cmd_baseioh, WDC_REG_NPORTS << 4);
    461 
    462 	/* Unmap DMA registers. */
    463 	/* XXX unmapiodev(sc->sc_dmareg); */
    464 	/* XXX free(sc->sc_dmacmd); */
    465 
    466 	return 0;
    467 }
    468 
    469 int
    470 wdc_obio_dma_init(void *v, int channel, int drive, void *databuf,
    471 	size_t datalen, int flags)
    472 {
    473 	struct wdc_obio_softc *sc = v;
    474 	vaddr_t va = (vaddr_t)databuf;
    475 	dbdma_command_t *cmdp;
    476 	u_int cmd, offset;
    477 	int read = flags & WDC_DMA_READ;
    478 
    479 	cmdp = sc->sc_dmacmd;
    480 	cmd = read ? DBDMA_CMD_IN_MORE : DBDMA_CMD_OUT_MORE;
    481 
    482 	offset = va & PGOFSET;
    483 
    484 	/* if va is not page-aligned, setup the first page */
    485 	if (offset != 0) {
    486 		int rest = PAGE_SIZE - offset;	/* the rest of the page */
    487 
    488 		if (datalen > rest) {		/* if continues to next page */
    489 			DBDMA_BUILD(cmdp, cmd, 0, rest, vtophys(va),
    490 				DBDMA_INT_NEVER, DBDMA_WAIT_NEVER,
    491 				DBDMA_BRANCH_NEVER);
    492 			datalen -= rest;
    493 			va += rest;
    494 			cmdp++;
    495 		}
    496 	}
    497 
    498 	/* now va is page-aligned */
    499 	while (datalen > PAGE_SIZE) {
    500 		DBDMA_BUILD(cmdp, cmd, 0, PAGE_SIZE, vtophys(va),
    501 			DBDMA_INT_NEVER, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
    502 		datalen -= PAGE_SIZE;
    503 		va += PAGE_SIZE;
    504 		cmdp++;
    505 	}
    506 
    507 	/* the last page (datalen <= PAGE_SIZE here) */
    508 	cmd = read ? DBDMA_CMD_IN_LAST : DBDMA_CMD_OUT_LAST;
    509 	DBDMA_BUILD(cmdp, cmd, 0, datalen, vtophys(va),
    510 		DBDMA_INT_NEVER, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
    511 	cmdp++;
    512 
    513 	DBDMA_BUILD(cmdp, DBDMA_CMD_STOP, 0, 0, 0,
    514 		DBDMA_INT_NEVER, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
    515 
    516 	return 0;
    517 }
    518 
    519 void
    520 wdc_obio_dma_start(void *v, int channel, int drive)
    521 {
    522 	struct wdc_obio_softc *sc = v;
    523 
    524 	dbdma_start(sc->sc_dmareg, sc->sc_dmacmd);
    525 }
    526 
    527 int
    528 wdc_obio_dma_finish(void *v, int channel, int drive, int read)
    529 {
    530 	struct wdc_obio_softc *sc = v;
    531 
    532 	dbdma_stop(sc->sc_dmareg);
    533 	return 0;
    534 }
    535