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wdc_obio.c revision 1.30
      1 /*	$NetBSD: wdc_obio.c,v 1.30 2003/12/03 12:09:32 bouyer 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 1.30 2003/12/03 12:09:32 bouyer 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 
     52 #include <dev/ata/atareg.h>
     53 #include <dev/ata/atavar.h>
     54 #include <dev/ic/wdcvar.h>
     55 
     56 #include <dev/ofw/openfirm.h>
     57 
     58 #include <macppc/dev/dbdma.h>
     59 
     60 #define WDC_REG_NPORTS		8
     61 #define WDC_AUXREG_OFFSET	0x16
     62 #define WDC_DEFAULT_PIO_IRQ	13	/* XXX */
     63 #define WDC_DEFAULT_DMA_IRQ	2	/* XXX */
     64 
     65 #define WDC_OPTIONS_DMA 0x01
     66 
     67 /*
     68  * XXX This code currently doesn't even try to allow 32-bit data port use.
     69  */
     70 
     71 struct wdc_obio_softc {
     72 	struct wdc_softc sc_wdcdev;
     73 	struct channel_softc *wdc_chanptr;
     74 	struct channel_softc wdc_channel;
     75 	dbdma_regmap_t *sc_dmareg;
     76 	dbdma_command_t	*sc_dmacmd;
     77 	u_int sc_dmaconf[2];	/* per target value of CONFIG_REG */
     78 	void *sc_ih;
     79 };
     80 
     81 int wdc_obio_probe __P((struct device *, struct cfdata *, void *));
     82 void wdc_obio_attach __P((struct device *, struct device *, void *));
     83 int wdc_obio_detach __P((struct device *, int));
     84 int wdc_obio_dma_init __P((void *, int, int, void *, size_t, int));
     85 void wdc_obio_dma_start __P((void *, int, int));
     86 int wdc_obio_dma_finish __P((void *, int, int, int));
     87 
     88 static void wdc_obio_select __P((struct channel_softc *, int));
     89 static void adjust_timing __P((struct channel_softc *));
     90 static void ata4_adjust_timing __P((struct channel_softc *));
     91 
     92 CFATTACH_DECL(wdc_obio, sizeof(struct wdc_obio_softc),
     93     wdc_obio_probe, wdc_obio_attach, wdc_obio_detach, wdcactivate);
     94 
     95 int
     96 wdc_obio_probe(parent, match, aux)
     97 	struct device *parent;
     98 	struct cfdata *match;
     99 	void *aux;
    100 {
    101 	struct confargs *ca = aux;
    102 	char compat[32];
    103 
    104 	/* XXX should not use name */
    105 	if (strcmp(ca->ca_name, "ATA") == 0 ||
    106 	    strcmp(ca->ca_name, "ata") == 0 ||
    107 	    strcmp(ca->ca_name, "ata0") == 0 ||
    108 	    strcmp(ca->ca_name, "ide") == 0)
    109 		return 1;
    110 
    111 	memset(compat, 0, sizeof(compat));
    112 	OF_getprop(ca->ca_node, "compatible", compat, sizeof(compat));
    113 	if (strcmp(compat, "heathrow-ata") == 0 ||
    114 	    strcmp(compat, "keylargo-ata") == 0)
    115 		return 1;
    116 
    117 	return 0;
    118 }
    119 
    120 void
    121 wdc_obio_attach(parent, self, aux)
    122 	struct device *parent, *self;
    123 	void *aux;
    124 {
    125 	struct wdc_obio_softc *sc = (void *)self;
    126 	struct confargs *ca = aux;
    127 	struct channel_softc *chp = &sc->wdc_channel;
    128 	int intr, i;
    129 	int use_dma = 0;
    130 	char path[80];
    131 
    132 	if (sc->sc_wdcdev.sc_dev.dv_cfdata->cf_flags & WDC_OPTIONS_DMA) {
    133 		if (ca->ca_nreg >= 16 || ca->ca_nintr == -1)
    134 			use_dma = 1;	/* XXX Don't work yet. */
    135 	}
    136 
    137 	if (ca->ca_nintr >= 4 && ca->ca_nreg >= 8) {
    138 		intr = ca->ca_intr[0];
    139 		printf(" irq %d", intr);
    140 	} else if (ca->ca_nintr == -1) {
    141 		intr = WDC_DEFAULT_PIO_IRQ;
    142 		printf(" irq property not found; using %d", intr);
    143 	} else {
    144 		printf(": couldn't get irq property\n");
    145 		return;
    146 	}
    147 
    148 	if (use_dma)
    149 		printf(": DMA transfer");
    150 
    151 	printf("\n");
    152 
    153 	chp->cmd_iot = chp->ctl_iot =
    154 		macppc_make_bus_space_tag(ca->ca_baseaddr + ca->ca_reg[0], 4);
    155 
    156 	if (bus_space_map(chp->cmd_iot, 0, WDC_REG_NPORTS, 0,
    157 	    &chp->cmd_baseioh) ||
    158 	    bus_space_subregion(chp->cmd_iot, chp->cmd_baseioh,
    159 			WDC_AUXREG_OFFSET, 1, &chp->ctl_ioh)) {
    160 		printf("%s: couldn't map registers\n",
    161 			sc->sc_wdcdev.sc_dev.dv_xname);
    162 		return;
    163 	}
    164 	for (i = 0; i < WDC_NREG; i++) {
    165 		if (bus_space_subregion(chp->cmd_iot, chp->cmd_baseioh, i,
    166 		    i == 0 ? 4 : 1, &chp->cmd_iohs[i]) != 0) {
    167 			bus_space_unmap(chp->cmd_iot, chp->cmd_baseioh,
    168 			    WDC_REG_NPORTS);
    169 			printf("%s: couldn't subregion registers\n",
    170 			    sc->sc_wdcdev.sc_dev.dv_xname);
    171 			return;
    172 		}
    173 	}
    174 #if 0
    175 	chp->data32iot = chp->cmd_iot;
    176 	chp->data32ioh = chp->cmd_ioh;
    177 #endif
    178 
    179 	sc->sc_ih = intr_establish(intr, IST_LEVEL, IPL_BIO, wdcintr, chp);
    180 
    181 	if (use_dma) {
    182 		sc->sc_dmacmd = dbdma_alloc(sizeof(dbdma_command_t) * 20);
    183 		sc->sc_dmareg = mapiodev(ca->ca_baseaddr + ca->ca_reg[2],
    184 					 ca->ca_reg[3]);
    185 		sc->sc_wdcdev.cap |= WDC_CAPABILITY_DMA;
    186 		sc->sc_wdcdev.DMA_cap = 2;
    187 		if (strcmp(ca->ca_name, "ata-4") == 0) {
    188 			sc->sc_wdcdev.cap |= WDC_CAPABILITY_UDMA;
    189 			sc->sc_wdcdev.UDMA_cap = 4;
    190 			sc->sc_wdcdev.set_modes = ata4_adjust_timing;
    191 		} else {
    192 			sc->sc_wdcdev.set_modes = adjust_timing;
    193 		}
    194 #ifdef notyet
    195 		/* Minimum cycle time is 150ns (DMA MODE 1) on ohare. */
    196 		if (ohare) {
    197 			sc->sc_wdcdev.PIO_cap = 3;
    198 			sc->sc_wdcdev.DMA_cap = 1;
    199 		}
    200 #endif
    201 	} else {
    202 		/* all non-DMA controllers can use adjust_timing */
    203 		sc->sc_wdcdev.set_modes = adjust_timing;
    204 	}
    205 
    206 	sc->sc_wdcdev.PIO_cap = 4;
    207 	sc->sc_wdcdev.cap |= WDC_CAPABILITY_DATA16 | WDC_CAPABILITY_MODE;
    208 	sc->wdc_chanptr = chp;
    209 	sc->sc_wdcdev.channels = &sc->wdc_chanptr;
    210 	sc->sc_wdcdev.nchannels = 1;
    211 	sc->sc_wdcdev.dma_arg = sc;
    212 	sc->sc_wdcdev.dma_init = wdc_obio_dma_init;
    213 	sc->sc_wdcdev.dma_start = wdc_obio_dma_start;
    214 	sc->sc_wdcdev.dma_finish = wdc_obio_dma_finish;
    215 	chp->channel = 0;
    216 	chp->wdc = &sc->sc_wdcdev;
    217 	chp->ch_queue = malloc(sizeof(struct channel_queue),
    218 		M_DEVBUF, M_NOWAIT);
    219 	if (chp->ch_queue == NULL) {
    220 		printf("%s: can't allocate memory for command queue",
    221 		sc->sc_wdcdev.sc_dev.dv_xname);
    222 		return;
    223 	}
    224 
    225 #define OHARE_FEATURE_REG	0xf3000038
    226 
    227 	/* XXX Enable wdc1 by feature reg. */
    228 	memset(path, 0, sizeof(path));
    229 	OF_package_to_path(ca->ca_node, path, sizeof(path));
    230 	if (strcmp(path, "/bandit@F2000000/ohare@10/ata@21000") == 0) {
    231 		u_int x;
    232 
    233 		x = in32rb(OHARE_FEATURE_REG);
    234 		x |= 8;
    235 		out32rb(OHARE_FEATURE_REG, x);
    236 	}
    237 
    238 	wdcattach(chp);
    239 }
    240 
    241 /* Multiword DMA transfer timings */
    242 struct ide_timings {
    243 	int cycle;	/* minimum cycle time [ns] */
    244 	int active;	/* minimum command active time [ns] */
    245 };
    246 static struct ide_timings pio_timing[5] = {
    247 	{ 600, 180 },    /* Mode 0 */
    248 	{ 390, 150 },    /*      1 */
    249 	{ 240, 105 },    /*      2 */
    250 	{ 180,  90 },    /*      3 */
    251 	{ 120,  75 }     /*      4 */
    252 };
    253 static struct ide_timings dma_timing[3] = {
    254 	{ 480, 240 },	/* Mode 0 */
    255 	{ 165,  90 },	/* Mode 1 */
    256 	{ 120,  75 }	/* Mode 2 */
    257 };
    258 
    259 static struct ide_timings udma_timing[5] = {
    260 	{120, 180},	/* Mode 0 */
    261 	{ 90, 150},	/* Mode 1 */
    262 	{ 60, 120},	/* Mode 2 */
    263 	{ 45, 90},	/* Mode 3 */
    264 	{ 30, 90}	/* Mode 4 */
    265 };
    266 
    267 #define TIME_TO_TICK(time) howmany((time), 30)
    268 #define PIO_REC_OFFSET 4
    269 #define PIO_REC_MIN 1
    270 #define PIO_ACT_MIN 1
    271 #define DMA_REC_OFFSET 1
    272 #define DMA_REC_MIN 1
    273 #define DMA_ACT_MIN 1
    274 
    275 #define ATA4_TIME_TO_TICK(time)  howmany((time), 15) /* 15 ns clock */
    276 
    277 #define CONFIG_REG (0x200 >> 4)		/* IDE access timing register */
    278 
    279 void
    280 wdc_obio_select(chp, drive)
    281 	struct channel_softc *chp;
    282 	int drive;
    283 {
    284 	struct wdc_obio_softc *sc = (struct wdc_obio_softc *)chp->wdc;
    285 	bus_space_write_4(chp->cmd_iot, chp->cmd_baseioh,
    286 			CONFIG_REG, sc->sc_dmaconf[drive]);
    287 }
    288 
    289 void
    290 adjust_timing(chp)
    291 	struct channel_softc *chp;
    292 {
    293 	struct wdc_obio_softc *sc = (struct wdc_obio_softc *)chp->wdc;
    294 	int drive;
    295 	int min_cycle, min_active;
    296 	int cycle_tick, act_tick, inact_tick, half_tick;
    297 
    298 	for (drive = 0; drive < 2; drive++) {
    299 		u_int conf = 0;
    300 		struct ata_drive_datas *drvp;
    301 
    302 		drvp = &chp->ch_drive[drive];
    303 		/* set up pio mode timings */
    304 		if (drvp->drive_flags & DRIVE) {
    305 			int piomode = drvp->PIO_mode;
    306 			min_cycle = pio_timing[piomode].cycle;
    307 			min_active = pio_timing[piomode].active;
    308 
    309 			cycle_tick = TIME_TO_TICK(min_cycle);
    310 			act_tick = TIME_TO_TICK(min_active);
    311 			if (act_tick < PIO_ACT_MIN)
    312 				act_tick = PIO_ACT_MIN;
    313 			inact_tick = cycle_tick - act_tick - PIO_REC_OFFSET;
    314 			if (inact_tick < PIO_REC_MIN)
    315 				inact_tick = PIO_REC_MIN;
    316 			/* mask: 0x000007ff */
    317 			conf |= (inact_tick << 5) | act_tick;
    318 		}
    319 		/* Set up DMA mode timings */
    320 		if (drvp->drive_flags & DRIVE_DMA) {
    321 			int dmamode = drvp->DMA_mode;
    322 			min_cycle = dma_timing[dmamode].cycle;
    323 			min_active = dma_timing[dmamode].active;
    324 			cycle_tick = TIME_TO_TICK(min_cycle);
    325 			act_tick = TIME_TO_TICK(min_active);
    326 			inact_tick = cycle_tick - act_tick - DMA_REC_OFFSET;
    327 			if (inact_tick < DMA_REC_MIN)
    328 				inact_tick = DMA_REC_MIN;
    329 			half_tick = 0;	/* XXX */
    330 			/* mask: 0xfffff800 */
    331 			conf |=
    332 					(half_tick << 21) |
    333 					(inact_tick << 16) | (act_tick << 11);
    334 		}
    335 #ifdef DEBUG
    336 		if (conf) {
    337 			printf("conf[%d] = 0x%x, cyc = %d (%d ns), act = %d (%d ns), inact = %d\n",
    338 					drive, conf, cycle_tick, min_cycle, act_tick, min_active, inact_tick);
    339 		}
    340 #endif
    341 		sc->sc_dmaconf[drive] = conf;
    342 	}
    343 	sc->sc_wdcdev.cap &= ~WDC_CAPABILITY_SELECT;
    344 	sc->sc_wdcdev.select = 0;
    345 	if (sc->sc_dmaconf[0]) {
    346 		wdc_obio_select(chp,0);
    347 		if (sc->sc_dmaconf[1] && (sc->sc_dmaconf[0] != sc->sc_dmaconf[1])) {
    348 			sc->sc_wdcdev.select = wdc_obio_select;
    349 			sc->sc_wdcdev.cap |= WDC_CAPABILITY_SELECT;
    350 		}
    351 	} else if (sc->sc_dmaconf[1]) {
    352 		wdc_obio_select(chp,1);
    353 	}
    354 }
    355 
    356 void
    357 ata4_adjust_timing(chp)
    358 	struct channel_softc *chp;
    359 {
    360 	struct wdc_obio_softc *sc = (struct wdc_obio_softc *)chp->wdc;
    361 	int drive;
    362 	int min_cycle, min_active;
    363 	int cycle_tick, act_tick, inact_tick;
    364 
    365 	for (drive = 0; drive < 2; drive++) {
    366 		u_int conf = 0;
    367 		struct ata_drive_datas *drvp;
    368 
    369 		drvp = &chp->ch_drive[drive];
    370 		/* set up pio mode timings */
    371 
    372 		if (drvp->drive_flags & DRIVE) {
    373 			int piomode = drvp->PIO_mode;
    374 			min_cycle = pio_timing[piomode].cycle;
    375 			min_active = pio_timing[piomode].active;
    376 
    377 			cycle_tick = ATA4_TIME_TO_TICK(min_cycle);
    378 			act_tick = ATA4_TIME_TO_TICK(min_active);
    379 			inact_tick = cycle_tick - act_tick;
    380 			/* mask: 0x000003ff */
    381 			conf |= (inact_tick << 5) | act_tick;
    382 		}
    383 		/* set up dma mode timings */
    384 		if (drvp->drive_flags & DRIVE_DMA) {
    385 			int dmamode = drvp->DMA_mode;
    386 			min_cycle = dma_timing[dmamode].cycle;
    387 			min_active = dma_timing[dmamode].active;
    388 			cycle_tick = ATA4_TIME_TO_TICK(min_cycle);
    389 			act_tick = ATA4_TIME_TO_TICK(min_active);
    390 			inact_tick = cycle_tick - act_tick;
    391 			/* mask: 0x001ffc00 */
    392 			conf |= (act_tick << 10) | (inact_tick << 15);
    393 		}
    394 		/* set up udma mode timings */
    395 		if (drvp->drive_flags & DRIVE_UDMA) {
    396 			int udmamode = drvp->UDMA_mode;
    397 			min_cycle = udma_timing[udmamode].cycle;
    398 			min_active = udma_timing[udmamode].active;
    399 			act_tick = ATA4_TIME_TO_TICK(min_active);
    400 			cycle_tick = ATA4_TIME_TO_TICK(min_cycle);
    401 			/* mask: 0x1ff00000 */
    402 			conf |= (cycle_tick << 21) | (act_tick << 25) | 0x100000;
    403 		}
    404 #ifdef DEBUG
    405 		if (conf) {
    406 			printf("ata4 conf[%d] = 0x%x, cyc = %d (%d ns), act = %d (%d ns), inact = %d\n",
    407 					drive, conf, cycle_tick, min_cycle, act_tick, min_active, inact_tick);
    408 		}
    409 #endif
    410 		sc->sc_dmaconf[drive] = conf;
    411 	}
    412 	sc->sc_wdcdev.cap &= ~WDC_CAPABILITY_SELECT;
    413 	sc->sc_wdcdev.select = 0;
    414 	if (sc->sc_dmaconf[0]) {
    415 		wdc_obio_select(chp,0);
    416 		if (sc->sc_dmaconf[1] && (sc->sc_dmaconf[0] != sc->sc_dmaconf[1])) {
    417 			sc->sc_wdcdev.select = wdc_obio_select;
    418 			sc->sc_wdcdev.cap |= WDC_CAPABILITY_SELECT;
    419 		}
    420 	} else if (sc->sc_dmaconf[1]) {
    421 		wdc_obio_select(chp,1);
    422 	}
    423 }
    424 
    425 int
    426 wdc_obio_detach(self, flags)
    427 	struct device *self;
    428 	int flags;
    429 {
    430 	struct wdc_obio_softc *sc = (void *)self;
    431 	int error;
    432 
    433 	if ((error = wdcdetach(self, flags)) != 0)
    434 		return error;
    435 
    436 	intr_disestablish(sc->sc_ih);
    437 
    438 	free(sc->wdc_channel.ch_queue, M_DEVBUF);
    439 
    440 	/* Unmap our i/o space. */
    441 	bus_space_unmap(chp->cmd_iot, chp->cmd_ioh, WDC_REG_NPORTS);
    442 
    443 	/* Unmap DMA registers. */
    444 	/* XXX unmapiodev(sc->sc_dmareg); */
    445 	/* XXX free(sc->sc_dmacmd); */
    446 
    447 	return 0;
    448 }
    449 
    450 int
    451 wdc_obio_dma_init(v, channel, drive, databuf, datalen, flags)
    452 	void *v;
    453 	void *databuf;
    454 	size_t datalen;
    455 	int flags;
    456 {
    457 	struct wdc_obio_softc *sc = v;
    458 	vaddr_t va = (vaddr_t)databuf;
    459 	dbdma_command_t *cmdp;
    460 	u_int cmd, offset;
    461 	int read = flags & WDC_DMA_READ;
    462 
    463 	cmdp = sc->sc_dmacmd;
    464 	cmd = read ? DBDMA_CMD_IN_MORE : DBDMA_CMD_OUT_MORE;
    465 
    466 	offset = va & PGOFSET;
    467 
    468 	/* if va is not page-aligned, setup the first page */
    469 	if (offset != 0) {
    470 		int rest = PAGE_SIZE - offset;	/* the rest of the page */
    471 
    472 		if (datalen > rest) {		/* if continues to next page */
    473 			DBDMA_BUILD(cmdp, cmd, 0, rest, vtophys(va),
    474 				DBDMA_INT_NEVER, DBDMA_WAIT_NEVER,
    475 				DBDMA_BRANCH_NEVER);
    476 			datalen -= rest;
    477 			va += rest;
    478 			cmdp++;
    479 		}
    480 	}
    481 
    482 	/* now va is page-aligned */
    483 	while (datalen > PAGE_SIZE) {
    484 		DBDMA_BUILD(cmdp, cmd, 0, PAGE_SIZE, vtophys(va),
    485 			DBDMA_INT_NEVER, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
    486 		datalen -= PAGE_SIZE;
    487 		va += PAGE_SIZE;
    488 		cmdp++;
    489 	}
    490 
    491 	/* the last page (datalen <= PAGE_SIZE here) */
    492 	cmd = read ? DBDMA_CMD_IN_LAST : DBDMA_CMD_OUT_LAST;
    493 	DBDMA_BUILD(cmdp, cmd, 0, datalen, vtophys(va),
    494 		DBDMA_INT_NEVER, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
    495 	cmdp++;
    496 
    497 	DBDMA_BUILD(cmdp, DBDMA_CMD_STOP, 0, 0, 0,
    498 		DBDMA_INT_NEVER, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
    499 
    500 	return 0;
    501 }
    502 
    503 void
    504 wdc_obio_dma_start(v, channel, drive)
    505 	void *v;
    506 	int channel, drive;
    507 {
    508 	struct wdc_obio_softc *sc = v;
    509 
    510 	dbdma_start(sc->sc_dmareg, sc->sc_dmacmd);
    511 }
    512 
    513 int
    514 wdc_obio_dma_finish(v, channel, drive, read)
    515 	void *v;
    516 	int channel, drive;
    517 	int read;
    518 {
    519 	struct wdc_obio_softc *sc = v;
    520 
    521 	dbdma_stop(sc->sc_dmareg);
    522 	return 0;
    523 }
    524