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asc.c revision 1.5.6.1
      1  1.5.6.1     tron /*	$NetBSD: asc.c,v 1.5.6.1 2002/11/01 11:13:55 tron Exp $	*/
      2      1.1  reinoud 
      3      1.1  reinoud /*
      4      1.1  reinoud  * Copyright (c) 2001 Richard Earnshaw
      5      1.1  reinoud  * All rights reserved.
      6      1.1  reinoud  *
      7      1.1  reinoud  * 1. Redistributions of source code must retain the above copyright
      8      1.1  reinoud  *    notice, this list of conditions and the following disclaimer.
      9      1.1  reinoud  * 2. Redistributions in binary form must reproduce the above copyright
     10      1.1  reinoud  *    notice, this list of conditions and the following disclaimer in the
     11      1.1  reinoud  *    documentation and/or other materials provided with the distribution.
     12      1.1  reinoud  * 3. The name of the company nor the name of the author may be used to
     13      1.1  reinoud  *    endorse or promote products derived from this software without specific
     14      1.1  reinoud  *    prior written permission.
     15      1.1  reinoud  *
     16      1.1  reinoud  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
     17      1.1  reinoud  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     18      1.1  reinoud  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     19      1.1  reinoud  * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
     20      1.1  reinoud  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     21      1.1  reinoud  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     22      1.1  reinoud  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     23      1.1  reinoud  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     24      1.1  reinoud  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     25      1.1  reinoud  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     26      1.1  reinoud  * POSSIBILITY OF SUCH DAMAGE.
     27      1.1  reinoud  *
     28      1.1  reinoud  *
     29      1.1  reinoud  * Copyright (c) 1996 Mark Brinicombe
     30      1.1  reinoud  * Copyright (c) 1982, 1990 The Regents of the University of California.
     31      1.1  reinoud  * All rights reserved.
     32      1.1  reinoud  *
     33      1.1  reinoud  * Redistribution and use in source and binary forms, with or without
     34      1.1  reinoud  * modification, are permitted provided that the following conditions
     35      1.1  reinoud  * are met:
     36      1.1  reinoud  * 1. Redistributions of source code must retain the above copyright
     37      1.1  reinoud  *    notice, this list of conditions and the following disclaimer.
     38      1.1  reinoud  * 2. Redistributions in binary form must reproduce the above copyright
     39      1.1  reinoud  *    notice, this list of conditions and the following disclaimer in the
     40      1.1  reinoud  *    documentation and/or other materials provided with the distribution.
     41      1.1  reinoud  * 3. All advertising materials mentioning features or use of this software
     42      1.1  reinoud  *    must display the following acknowledgement:
     43      1.1  reinoud  *	This product includes software developed by the University of
     44      1.1  reinoud  *	California, Berkeley and its contributors.
     45      1.1  reinoud  * 4. Neither the name of the University nor the names of its contributors
     46      1.1  reinoud  *    may be used to endorse or promote products derived from this software
     47      1.1  reinoud  *    without specific prior written permission.
     48      1.1  reinoud  *
     49      1.1  reinoud  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     50      1.1  reinoud  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     51      1.1  reinoud  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     52      1.1  reinoud  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     53      1.1  reinoud  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     54      1.1  reinoud  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     55      1.1  reinoud  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     56      1.1  reinoud  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     57      1.1  reinoud  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     58      1.1  reinoud  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     59      1.1  reinoud  * SUCH DAMAGE.
     60      1.1  reinoud  *
     61      1.1  reinoud  *	from:ahsc.c
     62      1.1  reinoud  */
     63      1.1  reinoud 
     64      1.1  reinoud /*
     65      1.1  reinoud  * Driver for the Acorn SCSI card using the SBIC (WD33C93A) generic driver
     66      1.1  reinoud  *
     67      1.1  reinoud  * Thanks to Acorn for supplying programming information on this card.
     68      1.1  reinoud  */
     69      1.1  reinoud 
     70      1.1  reinoud /* #define ASC_DMAMAP_DEBUG */
     71      1.1  reinoud /* #define DEBUG */
     72      1.1  reinoud 
     73      1.1  reinoud #include "opt_ddb.h"
     74      1.1  reinoud 
     75      1.1  reinoud #include <sys/param.h>
     76      1.4    bjh21 
     77  1.5.6.1     tron __KERNEL_RCSID(0, "$NetBSD: asc.c,v 1.5.6.1 2002/11/01 11:13:55 tron Exp $");
     78      1.4    bjh21 
     79      1.1  reinoud #include <sys/systm.h>
     80      1.1  reinoud #include <sys/kernel.h>
     81      1.1  reinoud #include <sys/device.h>
     82      1.1  reinoud #include <sys/buf.h>
     83      1.1  reinoud 
     84      1.1  reinoud #include <uvm/uvm_extern.h>
     85      1.1  reinoud 
     86      1.1  reinoud #include <machine/bus.h>
     87      1.3  thorpej #include <machine/intr.h>
     88      1.1  reinoud #include <machine/bootconfig.h>		/* asc_poll */
     89      1.1  reinoud 
     90      1.1  reinoud #include <dev/scsipi/scsi_all.h>
     91      1.1  reinoud #include <dev/scsipi/scsipi_all.h>
     92      1.1  reinoud #include <dev/scsipi/scsiconf.h>
     93      1.1  reinoud 
     94      1.2  thorpej #include <arm/arm32/katelib.h>
     95      1.1  reinoud 
     96      1.1  reinoud #include <dev/podulebus/podules.h>
     97      1.1  reinoud #include <dev/podulebus/powerromreg.h>
     98      1.1  reinoud 
     99      1.1  reinoud #include <acorn32/podulebus/podulebus.h>
    100      1.1  reinoud #include <acorn32/podulebus/sbicreg.h>
    101      1.1  reinoud #include <acorn32/podulebus/sbicvar.h>
    102      1.1  reinoud #include <acorn32/podulebus/ascreg.h>
    103      1.1  reinoud #include <acorn32/podulebus/ascvar.h>
    104      1.1  reinoud 
    105      1.1  reinoud void ascattach		(struct device *, struct device *, void *);
    106      1.1  reinoud int  ascmatch		(struct device *, struct cfdata *, void *);
    107      1.1  reinoud 
    108      1.1  reinoud void asc_enintr		(struct sbic_softc *);
    109      1.1  reinoud 
    110      1.1  reinoud int  asc_dmaok		(void *, bus_dma_tag_t, struct sbic_acb *);
    111      1.1  reinoud int  asc_dmasetup	(void *, bus_dma_tag_t, struct sbic_acb *, int);
    112      1.1  reinoud int  asc_dmanext	(void *, bus_dma_tag_t, struct sbic_acb *, int);
    113      1.1  reinoud void asc_dmastop	(void *, bus_dma_tag_t, struct sbic_acb *);
    114      1.1  reinoud void asc_dmafinish	(void *, bus_dma_tag_t, struct sbic_acb *);
    115      1.1  reinoud 
    116      1.1  reinoud void asc_scsi_request	(struct scsipi_channel *,
    117      1.1  reinoud 			 scsipi_adapter_req_t, void *);
    118      1.1  reinoud int  asc_intr		(void *);
    119      1.1  reinoud void asc_minphys	(struct buf *);
    120      1.1  reinoud 
    121      1.4    bjh21 void asc_dump		(void);
    122      1.4    bjh21 
    123      1.1  reinoud #ifdef DEBUG
    124      1.1  reinoud int	asc_dmadebug = 0;
    125      1.1  reinoud #endif
    126      1.1  reinoud 
    127      1.1  reinoud struct cfattach asc_ca = {
    128      1.1  reinoud 	sizeof(struct asc_softc), ascmatch, ascattach
    129      1.1  reinoud };
    130      1.1  reinoud 
    131      1.1  reinoud extern struct cfdriver asc_cd;
    132      1.1  reinoud 
    133      1.1  reinoud u_long scsi_nosync;
    134      1.1  reinoud int shift_nosync;
    135      1.1  reinoud 
    136      1.1  reinoud #if ASC_POLL > 0
    137      1.1  reinoud int asc_poll = 0;
    138      1.1  reinoud 
    139      1.1  reinoud #endif
    140      1.1  reinoud 
    141      1.1  reinoud int
    142      1.1  reinoud ascmatch(struct device *pdp, struct cfdata *cf, void *auxp)
    143      1.1  reinoud {
    144      1.1  reinoud 	struct podule_attach_args *pa = (struct podule_attach_args *)auxp;
    145      1.1  reinoud 
    146      1.1  reinoud 	/* Look for the card */
    147      1.1  reinoud 
    148      1.1  reinoud 	/* Standard ROM, skipping the MCS card that used the same ID. */
    149  1.5.6.1     tron 	if (pa->pa_product == PODULE_ACORN_SCSI &&
    150      1.1  reinoud 	    strncmp(pa->pa_podule->description, "MCS", 3) != 0)
    151      1.1  reinoud 		return 1;
    152      1.1  reinoud 
    153      1.1  reinoud 	/* PowerROM */
    154      1.1  reinoud         if (pa->pa_product == PODULE_ALSYSTEMS_SCSI &&
    155      1.1  reinoud             podulebus_initloader(pa) == 0 &&
    156      1.1  reinoud             podloader_callloader(pa, 0, 0) == PRID_ACORN_SCSI1)
    157      1.1  reinoud                 return 1;
    158      1.1  reinoud 
    159      1.1  reinoud 	return 0;
    160      1.1  reinoud }
    161      1.1  reinoud 
    162      1.1  reinoud void
    163      1.1  reinoud ascattach(struct device *pdp, struct device *dp, void *auxp)
    164      1.1  reinoud {
    165      1.1  reinoud 	/* volatile struct sdmac *rp;*/
    166      1.1  reinoud 	struct asc_softc *sc;
    167      1.1  reinoud 	struct sbic_softc *sbic;
    168      1.1  reinoud 	struct podule_attach_args *pa;
    169      1.1  reinoud 
    170      1.1  reinoud 	sc = (struct asc_softc *)dp;
    171      1.1  reinoud 	pa = (struct podule_attach_args *)auxp;
    172      1.1  reinoud 
    173      1.1  reinoud 	if (pa->pa_podule_number == -1)
    174      1.1  reinoud 		panic("Podule has disappeared !");
    175      1.1  reinoud 
    176      1.1  reinoud 	sc->sc_podule_number = pa->pa_podule_number;
    177      1.1  reinoud 	sc->sc_podule = pa->pa_podule;
    178      1.1  reinoud 	podules[sc->sc_podule_number].attached = 1;
    179      1.1  reinoud 
    180      1.1  reinoud 	sbic = &sc->sc_softc;
    181      1.1  reinoud 
    182      1.1  reinoud 	sbic->sc_enintr = asc_enintr;
    183      1.1  reinoud 	sbic->sc_dmaok = asc_dmaok;
    184      1.1  reinoud 	sbic->sc_dmasetup = asc_dmasetup;
    185      1.1  reinoud 	sbic->sc_dmanext = asc_dmanext;
    186      1.1  reinoud 	sbic->sc_dmastop = asc_dmastop;
    187      1.1  reinoud 	sbic->sc_dmafinish = asc_dmafinish;
    188      1.1  reinoud 
    189      1.1  reinoud 	/* Map sbic */
    190      1.1  reinoud 	sbic->sc_sbicp.sc_sbiciot = pa->pa_iot;
    191      1.1  reinoud 	if (bus_space_map (sbic->sc_sbicp.sc_sbiciot,
    192      1.1  reinoud 	    sc->sc_podule->mod_base + ASC_SBIC, ASC_SBIC_SPACE, 0,
    193      1.1  reinoud 	    &sbic->sc_sbicp.sc_sbicioh))
    194      1.1  reinoud 		panic("%s: Cannot map SBIC\n", dp->dv_xname);
    195      1.1  reinoud 
    196      1.1  reinoud 	sbic->sc_clkfreq = sbic_clock_override ? sbic_clock_override : 143;
    197      1.1  reinoud 
    198      1.1  reinoud 	sbic->sc_adapter.adapt_dev = &sbic->sc_dev;
    199      1.1  reinoud 	sbic->sc_adapter.adapt_nchannels = 1;
    200      1.1  reinoud 	sbic->sc_adapter.adapt_openings = 7;
    201      1.1  reinoud 	sbic->sc_adapter.adapt_max_periph = 1;
    202      1.1  reinoud 	sbic->sc_adapter.adapt_ioctl = NULL;
    203      1.1  reinoud 	sbic->sc_adapter.adapt_minphys = asc_minphys;
    204      1.1  reinoud 	sbic->sc_adapter.adapt_request = asc_scsi_request;
    205      1.1  reinoud 
    206      1.1  reinoud 	sbic->sc_channel.chan_adapter = &sbic->sc_adapter;
    207      1.1  reinoud 	sbic->sc_channel.chan_bustype = &scsi_bustype;
    208      1.1  reinoud 	sbic->sc_channel.chan_channel = 0;
    209      1.1  reinoud 	sbic->sc_channel.chan_ntargets = 8;
    210      1.1  reinoud 	sbic->sc_channel.chan_nluns = 8;
    211      1.1  reinoud 	sbic->sc_channel.chan_id = 7;
    212      1.1  reinoud 
    213      1.1  reinoud 	/* Provide an override for the host id */
    214      1.1  reinoud 	(void)get_bootconf_option(boot_args, "asc.hostid",
    215      1.1  reinoud 	    BOOTOPT_TYPE_INT, &sbic->sc_channel.chan_id);
    216      1.1  reinoud 
    217      1.1  reinoud 	printf(": hostid=%d", sbic->sc_channel.chan_id);
    218      1.1  reinoud 
    219      1.1  reinoud #if ASC_POLL > 0
    220      1.1  reinoud         if (boot_args)
    221      1.1  reinoud 		get_bootconf_option(boot_args, "ascpoll", BOOTOPT_TYPE_BOOLEAN,
    222      1.1  reinoud 		    &asc_poll);
    223      1.1  reinoud 
    224      1.1  reinoud 	if (asc_poll)
    225      1.1  reinoud 		printf(" polling");
    226      1.1  reinoud #endif
    227      1.1  reinoud 	printf("\n");
    228      1.1  reinoud 
    229      1.1  reinoud 	sc->sc_pagereg = sc->sc_podule->fast_base + ASC_PAGEREG;
    230      1.1  reinoud         sc->sc_intstat = sc->sc_podule->fast_base + ASC_INTSTATUS;
    231      1.1  reinoud 
    232      1.1  reinoud 	/* Reset the card */
    233      1.1  reinoud 
    234      1.1  reinoud 	WriteByte(sc->sc_pagereg, 0x80);
    235      1.1  reinoud 	DELAY(500000);
    236      1.1  reinoud 	WriteByte(sc->sc_pagereg, 0x00);
    237      1.1  reinoud 	DELAY(250000);
    238      1.1  reinoud 
    239      1.1  reinoud 	sbicinit(sbic);
    240      1.1  reinoud 
    241      1.1  reinoud 	/* If we are polling only, we don't need a interrupt handler.  */
    242      1.1  reinoud 
    243      1.1  reinoud #ifdef ASC_POLL
    244      1.1  reinoud 	if (!asc_poll)
    245      1.1  reinoud #endif
    246      1.1  reinoud 	{
    247      1.1  reinoud 		evcnt_attach_dynamic(&sc->sc_intrcnt, EVCNT_TYPE_INTR, NULL,
    248      1.1  reinoud 		    dp->dv_xname, "intr");
    249      1.1  reinoud 		sc->sc_ih = podulebus_irq_establish(pa->pa_ih, IPL_BIO,
    250      1.1  reinoud 		    asc_intr, sc, &sc->sc_intrcnt);
    251      1.1  reinoud 		if (sc->sc_ih == NULL)
    252      1.1  reinoud 			panic("%s: Cannot claim podule IRQ\n", dp->dv_xname);
    253      1.1  reinoud 	}
    254      1.1  reinoud 
    255      1.1  reinoud 	/*
    256      1.1  reinoud 	 * attach all scsi units on us
    257      1.1  reinoud 	 */
    258      1.1  reinoud 	config_found(dp, &sbic->sc_channel, scsiprint);
    259      1.1  reinoud }
    260      1.1  reinoud 
    261      1.1  reinoud 
    262      1.1  reinoud void
    263      1.1  reinoud asc_enintr(struct sbic_softc *sbicsc)
    264      1.1  reinoud {
    265      1.1  reinoud 	struct asc_softc *sc = (struct asc_softc *)sbicsc;
    266      1.1  reinoud 
    267      1.1  reinoud 	sbicsc->sc_flags |= SBICF_INTR;
    268      1.1  reinoud 	WriteByte(sc->sc_pagereg, 0x40);
    269      1.1  reinoud }
    270      1.1  reinoud 
    271      1.1  reinoud int
    272      1.1  reinoud asc_dmaok (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb)
    273      1.1  reinoud {
    274      1.1  reinoud 	return 0;
    275      1.1  reinoud }
    276      1.1  reinoud 
    277      1.1  reinoud int
    278      1.1  reinoud asc_dmasetup (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb, int dir)
    279      1.1  reinoud {
    280      1.1  reinoud 	printf("asc_dmasetup()");
    281      1.1  reinoud #ifdef DDB
    282      1.1  reinoud 	Debugger();
    283      1.1  reinoud #else
    284      1.1  reinoud 	panic("Hit a brick wall\n");
    285      1.1  reinoud #endif
    286      1.1  reinoud 	return 0;
    287      1.1  reinoud }
    288      1.1  reinoud 
    289      1.1  reinoud int
    290      1.1  reinoud asc_dmanext (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb, int dir)
    291      1.1  reinoud {
    292      1.1  reinoud 	printf("asc_dmanext()");
    293      1.1  reinoud #ifdef DDB
    294      1.1  reinoud 	Debugger();
    295      1.1  reinoud #else
    296      1.1  reinoud 	panic("Hit a brick wall\n");
    297      1.1  reinoud #endif
    298      1.1  reinoud 	return 0;
    299      1.1  reinoud }
    300      1.1  reinoud 
    301      1.1  reinoud void
    302      1.1  reinoud asc_dmastop (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb)
    303      1.1  reinoud {
    304      1.1  reinoud 	printf("asc_dmastop\n");
    305      1.1  reinoud }
    306      1.1  reinoud 
    307      1.1  reinoud void
    308      1.1  reinoud asc_dmafinish (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb)
    309      1.1  reinoud {
    310      1.1  reinoud 	printf("asc_dmafinish\n");
    311      1.1  reinoud }
    312      1.1  reinoud 
    313      1.1  reinoud void
    314      1.1  reinoud asc_dump(void)
    315      1.1  reinoud {
    316      1.1  reinoud 	int i;
    317      1.1  reinoud 
    318      1.1  reinoud 	for (i = 0; i < asc_cd.cd_ndevs; ++i)
    319      1.1  reinoud 		if (asc_cd.cd_devs[i])
    320      1.1  reinoud 			sbic_dump(asc_cd.cd_devs[i]);
    321      1.1  reinoud }
    322      1.1  reinoud 
    323      1.1  reinoud void
    324      1.1  reinoud asc_scsi_request(struct scsipi_channel *chan, scsipi_adapter_req_t req,
    325      1.1  reinoud     void *arg)
    326      1.1  reinoud {
    327      1.1  reinoud 	struct scsipi_xfer *xs;
    328      1.1  reinoud 
    329      1.1  reinoud 	switch (req) {
    330      1.1  reinoud 	case ADAPTER_REQ_RUN_XFER:
    331      1.1  reinoud 		xs = arg;
    332      1.1  reinoud 
    333      1.1  reinoud #if ASC_POLL > 0
    334      1.1  reinoud 		/* ensure command is polling for the moment */
    335      1.1  reinoud 
    336      1.1  reinoud 		if (asc_poll)
    337      1.1  reinoud 			xs->xs_control |= XS_CTL_POLL;
    338      1.1  reinoud #endif
    339      1.1  reinoud 
    340      1.1  reinoud /*		printf("id=%d lun=%dcmdlen=%d datalen=%d opcode=%02x flags=%08x status=%02x blk=%02x %02x\n",
    341      1.1  reinoud 		    xs->xs_periph->periph_target, xs->xs_periph->periph_lun, xs->cmdlen, xs->datalen, xs->cmd->opcode,
    342      1.1  reinoud 		    xs->xs_control, xs->status, xs->cmd->bytes[0], xs->cmd->bytes[1]);*/
    343      1.1  reinoud 
    344      1.1  reinoud 	default:
    345      1.1  reinoud 	}
    346      1.1  reinoud 	sbic_scsi_request(chan, req, arg);
    347      1.1  reinoud }
    348      1.1  reinoud 
    349      1.1  reinoud 
    350      1.1  reinoud int
    351      1.1  reinoud asc_intr(void *arg)
    352      1.1  reinoud {
    353      1.1  reinoud 	struct asc_softc *sc = arg;
    354      1.1  reinoud 	int intr;
    355      1.1  reinoud 
    356      1.1  reinoud 	/* printf("ascintr:");*/
    357      1.1  reinoud        	intr = ReadByte(sc->sc_intstat);
    358      1.1  reinoud 	/* printf("%02x\n", intr);*/
    359      1.1  reinoud 
    360      1.1  reinoud 	if (intr & IS_SBIC_IRQ)
    361      1.1  reinoud 		sbicintr((struct sbic_softc *)sc);
    362      1.1  reinoud 
    363      1.1  reinoud 	return 0;	/* Pass interrupt on down the chain */
    364      1.1  reinoud }
    365      1.1  reinoud 
    366      1.1  reinoud /*
    367      1.1  reinoud  * limit the transfer as required.
    368      1.1  reinoud  */
    369      1.1  reinoud void
    370      1.1  reinoud asc_minphys(struct buf *bp)
    371      1.1  reinoud {
    372      1.1  reinoud #if 0
    373      1.1  reinoud 	/*
    374      1.1  reinoud 	 * We must limit the DMA xfer size
    375      1.1  reinoud 	 */
    376      1.1  reinoud 	if (bp->b_bcount > MAX_DMA_LEN) {
    377      1.1  reinoud 		printf("asc: Reducing dma length\n");
    378      1.1  reinoud 		bp->b_bcount = MAX_DMA_LEN;
    379      1.1  reinoud 	}
    380      1.1  reinoud #endif
    381      1.1  reinoud 	minphys(bp);
    382      1.1  reinoud }
    383      1.1  reinoud 
    384