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      1  1.22  thorpej /*	$NetBSD: asc.c,v 1.22 2021/08/07 16:18:40 thorpej 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  1.13      agc  * Copyright (c) 1982, 1990 The Regents of the University of California.
     29  1.13      agc  * All rights reserved.
     30  1.13      agc  *
     31  1.13      agc  * Redistribution and use in source and binary forms, with or without
     32  1.13      agc  * modification, are permitted provided that the following conditions
     33  1.13      agc  * are met:
     34  1.13      agc  * 1. Redistributions of source code must retain the above copyright
     35  1.13      agc  *    notice, this list of conditions and the following disclaimer.
     36  1.13      agc  * 2. Redistributions in binary form must reproduce the above copyright
     37  1.13      agc  *    notice, this list of conditions and the following disclaimer in the
     38  1.13      agc  *    documentation and/or other materials provided with the distribution.
     39  1.13      agc  * 3. Neither the name of the University nor the names of its contributors
     40  1.13      agc  *    may be used to endorse or promote products derived from this software
     41  1.13      agc  *    without specific prior written permission.
     42  1.13      agc  *
     43  1.13      agc  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     44  1.13      agc  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     45  1.13      agc  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     46  1.13      agc  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     47  1.13      agc  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     48  1.13      agc  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     49  1.13      agc  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     50  1.13      agc  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     51  1.13      agc  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     52  1.13      agc  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     53  1.13      agc  * SUCH DAMAGE.
     54   1.1  reinoud  *
     55   1.1  reinoud  * Copyright (c) 1996 Mark Brinicombe
     56   1.1  reinoud  *
     57   1.1  reinoud  * Redistribution and use in source and binary forms, with or without
     58   1.1  reinoud  * modification, are permitted provided that the following conditions
     59   1.1  reinoud  * are met:
     60   1.1  reinoud  * 1. Redistributions of source code must retain the above copyright
     61   1.1  reinoud  *    notice, this list of conditions and the following disclaimer.
     62   1.1  reinoud  * 2. Redistributions in binary form must reproduce the above copyright
     63   1.1  reinoud  *    notice, this list of conditions and the following disclaimer in the
     64   1.1  reinoud  *    documentation and/or other materials provided with the distribution.
     65   1.1  reinoud  * 3. All advertising materials mentioning features or use of this software
     66   1.1  reinoud  *    must display the following acknowledgement:
     67   1.1  reinoud  *	This product includes software developed by the University of
     68   1.1  reinoud  *	California, Berkeley and its contributors.
     69   1.1  reinoud  * 4. Neither the name of the University nor the names of its contributors
     70   1.1  reinoud  *    may be used to endorse or promote products derived from this software
     71   1.1  reinoud  *    without specific prior written permission.
     72   1.1  reinoud  *
     73   1.1  reinoud  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     74   1.1  reinoud  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     75   1.1  reinoud  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     76   1.1  reinoud  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     77   1.1  reinoud  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     78   1.1  reinoud  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     79   1.1  reinoud  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     80   1.1  reinoud  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     81   1.1  reinoud  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     82   1.1  reinoud  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     83   1.1  reinoud  * SUCH DAMAGE.
     84   1.1  reinoud  *
     85   1.1  reinoud  *	from:ahsc.c
     86   1.1  reinoud  */
     87   1.1  reinoud 
     88   1.1  reinoud /*
     89   1.1  reinoud  * Driver for the Acorn SCSI card using the SBIC (WD33C93A) generic driver
     90   1.1  reinoud  *
     91   1.1  reinoud  * Thanks to Acorn for supplying programming information on this card.
     92   1.1  reinoud  */
     93   1.1  reinoud 
     94   1.1  reinoud /* #define ASC_DMAMAP_DEBUG */
     95   1.1  reinoud /* #define DEBUG */
     96   1.1  reinoud 
     97   1.1  reinoud #include "opt_ddb.h"
     98   1.1  reinoud 
     99   1.1  reinoud #include <sys/param.h>
    100   1.4    bjh21 
    101  1.22  thorpej __KERNEL_RCSID(0, "$NetBSD: asc.c,v 1.22 2021/08/07 16:18:40 thorpej Exp $");
    102   1.4    bjh21 
    103   1.1  reinoud #include <sys/systm.h>
    104   1.1  reinoud #include <sys/kernel.h>
    105   1.1  reinoud #include <sys/device.h>
    106   1.1  reinoud #include <sys/buf.h>
    107  1.18   dyoung #include <sys/bus.h>
    108   1.1  reinoud 
    109   1.1  reinoud #include <uvm/uvm_extern.h>
    110   1.1  reinoud 
    111   1.3  thorpej #include <machine/intr.h>
    112   1.1  reinoud #include <machine/bootconfig.h>		/* asc_poll */
    113   1.1  reinoud 
    114   1.1  reinoud #include <dev/scsipi/scsi_all.h>
    115   1.1  reinoud #include <dev/scsipi/scsipi_all.h>
    116   1.1  reinoud #include <dev/scsipi/scsiconf.h>
    117   1.1  reinoud 
    118   1.1  reinoud #include <dev/podulebus/podules.h>
    119   1.1  reinoud #include <dev/podulebus/powerromreg.h>
    120   1.1  reinoud 
    121   1.1  reinoud #include <acorn32/podulebus/podulebus.h>
    122   1.1  reinoud #include <acorn32/podulebus/sbicreg.h>
    123   1.1  reinoud #include <acorn32/podulebus/sbicvar.h>
    124   1.1  reinoud #include <acorn32/podulebus/ascreg.h>
    125   1.1  reinoud #include <acorn32/podulebus/ascvar.h>
    126   1.1  reinoud 
    127  1.17     matt void ascattach		(device_t, device_t, void *);
    128  1.17     matt int  ascmatch		(device_t, cfdata_t, void *);
    129   1.1  reinoud 
    130   1.1  reinoud void asc_enintr		(struct sbic_softc *);
    131   1.1  reinoud 
    132   1.1  reinoud int  asc_dmaok		(void *, bus_dma_tag_t, struct sbic_acb *);
    133   1.1  reinoud int  asc_dmasetup	(void *, bus_dma_tag_t, struct sbic_acb *, int);
    134   1.1  reinoud int  asc_dmanext	(void *, bus_dma_tag_t, struct sbic_acb *, int);
    135   1.1  reinoud void asc_dmastop	(void *, bus_dma_tag_t, struct sbic_acb *);
    136   1.1  reinoud void asc_dmafinish	(void *, bus_dma_tag_t, struct sbic_acb *);
    137   1.1  reinoud 
    138   1.1  reinoud int  asc_intr		(void *);
    139   1.1  reinoud void asc_minphys	(struct buf *);
    140   1.1  reinoud 
    141   1.4    bjh21 void asc_dump		(void);
    142   1.4    bjh21 
    143   1.1  reinoud #ifdef DEBUG
    144   1.1  reinoud int	asc_dmadebug = 0;
    145   1.1  reinoud #endif
    146   1.1  reinoud 
    147  1.19      chs CFATTACH_DECL_NEW(asc, sizeof(struct asc_softc),
    148  1.11  thorpej     ascmatch, ascattach, NULL, NULL);
    149   1.1  reinoud 
    150   1.1  reinoud extern struct cfdriver asc_cd;
    151   1.1  reinoud 
    152   1.1  reinoud u_long scsi_nosync;
    153   1.1  reinoud int shift_nosync;
    154   1.1  reinoud 
    155   1.1  reinoud #if ASC_POLL > 0
    156   1.1  reinoud int asc_poll = 0;
    157   1.1  reinoud 
    158   1.1  reinoud #endif
    159   1.1  reinoud 
    160   1.1  reinoud int
    161  1.19      chs ascmatch(device_t parent, cfdata_t cf, void *aux)
    162   1.1  reinoud {
    163  1.19      chs 	struct podule_attach_args *pa = aux;
    164   1.1  reinoud 
    165   1.1  reinoud 	/* Look for the card */
    166   1.1  reinoud 
    167   1.1  reinoud 	/* Standard ROM, skipping the MCS card that used the same ID. */
    168   1.6    bjh21 	if (pa->pa_product == PODULE_ACORN_SCSI &&
    169   1.1  reinoud 	    strncmp(pa->pa_podule->description, "MCS", 3) != 0)
    170   1.1  reinoud 		return 1;
    171   1.1  reinoud 
    172   1.1  reinoud 	/* PowerROM */
    173   1.1  reinoud         if (pa->pa_product == PODULE_ALSYSTEMS_SCSI &&
    174   1.1  reinoud             podulebus_initloader(pa) == 0 &&
    175   1.1  reinoud             podloader_callloader(pa, 0, 0) == PRID_ACORN_SCSI1)
    176   1.1  reinoud                 return 1;
    177   1.1  reinoud 
    178   1.1  reinoud 	return 0;
    179   1.1  reinoud }
    180   1.1  reinoud 
    181   1.1  reinoud void
    182  1.19      chs ascattach(device_t parent, device_t self, void *aux)
    183   1.1  reinoud {
    184   1.1  reinoud 	/* volatile struct sdmac *rp;*/
    185   1.1  reinoud 	struct asc_softc *sc;
    186   1.1  reinoud 	struct sbic_softc *sbic;
    187   1.1  reinoud 	struct podule_attach_args *pa;
    188   1.1  reinoud 
    189  1.19      chs 	sc = device_private(self);
    190  1.19      chs 	pa = aux;
    191   1.1  reinoud 
    192   1.1  reinoud 	if (pa->pa_podule_number == -1)
    193   1.1  reinoud 		panic("Podule has disappeared !");
    194   1.1  reinoud 
    195   1.1  reinoud 	sc->sc_podule_number = pa->pa_podule_number;
    196   1.1  reinoud 	sc->sc_podule = pa->pa_podule;
    197   1.1  reinoud 	podules[sc->sc_podule_number].attached = 1;
    198   1.1  reinoud 
    199   1.1  reinoud 	sbic = &sc->sc_softc;
    200   1.1  reinoud 
    201  1.19      chs 	sbic->sc_dev = self;
    202   1.1  reinoud 	sbic->sc_enintr = asc_enintr;
    203   1.1  reinoud 	sbic->sc_dmaok = asc_dmaok;
    204   1.1  reinoud 	sbic->sc_dmasetup = asc_dmasetup;
    205   1.1  reinoud 	sbic->sc_dmanext = asc_dmanext;
    206   1.1  reinoud 	sbic->sc_dmastop = asc_dmastop;
    207   1.1  reinoud 	sbic->sc_dmafinish = asc_dmafinish;
    208   1.1  reinoud 
    209   1.1  reinoud 	/* Map sbic */
    210   1.1  reinoud 	sbic->sc_sbicp.sc_sbiciot = pa->pa_iot;
    211   1.1  reinoud 	if (bus_space_map (sbic->sc_sbicp.sc_sbiciot,
    212   1.1  reinoud 	    sc->sc_podule->mod_base + ASC_SBIC, ASC_SBIC_SPACE, 0,
    213   1.1  reinoud 	    &sbic->sc_sbicp.sc_sbicioh))
    214  1.19      chs 		panic("%s: Cannot map SBIC", device_xname(self));
    215   1.1  reinoud 
    216   1.1  reinoud 	sbic->sc_clkfreq = sbic_clock_override ? sbic_clock_override : 143;
    217   1.1  reinoud 
    218  1.19      chs 	sbic->sc_adapter.adapt_dev = self;
    219   1.1  reinoud 	sbic->sc_adapter.adapt_nchannels = 1;
    220   1.1  reinoud 	sbic->sc_adapter.adapt_openings = 7;
    221   1.1  reinoud 	sbic->sc_adapter.adapt_max_periph = 1;
    222   1.1  reinoud 	sbic->sc_adapter.adapt_ioctl = NULL;
    223   1.1  reinoud 	sbic->sc_adapter.adapt_minphys = asc_minphys;
    224   1.7    bjh21 	sbic->sc_adapter.adapt_request = sbic_scsi_request;
    225   1.1  reinoud 
    226   1.1  reinoud 	sbic->sc_channel.chan_adapter = &sbic->sc_adapter;
    227   1.1  reinoud 	sbic->sc_channel.chan_bustype = &scsi_bustype;
    228   1.1  reinoud 	sbic->sc_channel.chan_channel = 0;
    229   1.1  reinoud 	sbic->sc_channel.chan_ntargets = 8;
    230   1.1  reinoud 	sbic->sc_channel.chan_nluns = 8;
    231   1.1  reinoud 	sbic->sc_channel.chan_id = 7;
    232   1.1  reinoud 
    233   1.1  reinoud 	/* Provide an override for the host id */
    234   1.1  reinoud 	(void)get_bootconf_option(boot_args, "asc.hostid",
    235   1.1  reinoud 	    BOOTOPT_TYPE_INT, &sbic->sc_channel.chan_id);
    236   1.1  reinoud 
    237   1.1  reinoud 	printf(": hostid=%d", sbic->sc_channel.chan_id);
    238   1.1  reinoud 
    239   1.1  reinoud #if ASC_POLL > 0
    240   1.1  reinoud         if (boot_args)
    241   1.1  reinoud 		get_bootconf_option(boot_args, "ascpoll", BOOTOPT_TYPE_BOOLEAN,
    242   1.1  reinoud 		    &asc_poll);
    243   1.1  reinoud 
    244   1.7    bjh21 	if (asc_poll) {
    245   1.7    bjh21 		sbic->sc_adapter.adapt_flags |= SCSIPI_ADAPT_POLL_ONLY;
    246   1.1  reinoud 		printf(" polling");
    247   1.7    bjh21 	}
    248   1.1  reinoud #endif
    249   1.1  reinoud 	printf("\n");
    250   1.1  reinoud 
    251   1.1  reinoud 	sc->sc_pagereg = sc->sc_podule->fast_base + ASC_PAGEREG;
    252   1.1  reinoud         sc->sc_intstat = sc->sc_podule->fast_base + ASC_INTSTATUS;
    253   1.1  reinoud 
    254   1.1  reinoud 	/* Reset the card */
    255   1.1  reinoud 
    256   1.1  reinoud 	WriteByte(sc->sc_pagereg, 0x80);
    257   1.1  reinoud 	DELAY(500000);
    258   1.1  reinoud 	WriteByte(sc->sc_pagereg, 0x00);
    259   1.1  reinoud 	DELAY(250000);
    260   1.1  reinoud 
    261   1.1  reinoud 	sbicinit(sbic);
    262   1.1  reinoud 
    263   1.1  reinoud 	/* If we are polling only, we don't need a interrupt handler.  */
    264   1.1  reinoud 
    265   1.1  reinoud #ifdef ASC_POLL
    266   1.1  reinoud 	if (!asc_poll)
    267   1.1  reinoud #endif
    268   1.1  reinoud 	{
    269   1.1  reinoud 		evcnt_attach_dynamic(&sc->sc_intrcnt, EVCNT_TYPE_INTR, NULL,
    270  1.19      chs 		    device_xname(self), "intr");
    271   1.1  reinoud 		sc->sc_ih = podulebus_irq_establish(pa->pa_ih, IPL_BIO,
    272   1.1  reinoud 		    asc_intr, sc, &sc->sc_intrcnt);
    273   1.1  reinoud 		if (sc->sc_ih == NULL)
    274  1.19      chs 			panic("%s: Cannot claim podule IRQ", device_xname(self));
    275   1.1  reinoud 	}
    276   1.1  reinoud 
    277   1.1  reinoud 	/*
    278   1.1  reinoud 	 * attach all scsi units on us
    279   1.1  reinoud 	 */
    280  1.22  thorpej 	config_found(self, &sbic->sc_channel, scsiprint, CFARGS_NONE);
    281   1.1  reinoud }
    282   1.1  reinoud 
    283   1.1  reinoud 
    284   1.1  reinoud void
    285   1.1  reinoud asc_enintr(struct sbic_softc *sbicsc)
    286   1.1  reinoud {
    287   1.1  reinoud 	struct asc_softc *sc = (struct asc_softc *)sbicsc;
    288   1.1  reinoud 
    289   1.1  reinoud 	sbicsc->sc_flags |= SBICF_INTR;
    290   1.1  reinoud 	WriteByte(sc->sc_pagereg, 0x40);
    291   1.1  reinoud }
    292   1.1  reinoud 
    293   1.1  reinoud int
    294   1.1  reinoud asc_dmaok (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb)
    295   1.1  reinoud {
    296   1.1  reinoud 	return 0;
    297   1.1  reinoud }
    298   1.1  reinoud 
    299   1.1  reinoud int
    300   1.1  reinoud asc_dmasetup (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb, int dir)
    301   1.1  reinoud {
    302   1.1  reinoud 	printf("asc_dmasetup()");
    303   1.1  reinoud #ifdef DDB
    304   1.1  reinoud 	Debugger();
    305   1.1  reinoud #else
    306   1.8   provos 	panic("Hit a brick wall");
    307   1.1  reinoud #endif
    308   1.1  reinoud 	return 0;
    309   1.1  reinoud }
    310   1.1  reinoud 
    311   1.1  reinoud int
    312   1.1  reinoud asc_dmanext (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb, int dir)
    313   1.1  reinoud {
    314   1.1  reinoud 	printf("asc_dmanext()");
    315   1.1  reinoud #ifdef DDB
    316   1.1  reinoud 	Debugger();
    317   1.1  reinoud #else
    318   1.8   provos 	panic("Hit a brick wall");
    319   1.1  reinoud #endif
    320   1.1  reinoud 	return 0;
    321   1.1  reinoud }
    322   1.1  reinoud 
    323   1.1  reinoud void
    324   1.1  reinoud asc_dmastop (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb)
    325   1.1  reinoud {
    326   1.1  reinoud 	printf("asc_dmastop\n");
    327   1.1  reinoud }
    328   1.1  reinoud 
    329   1.1  reinoud void
    330   1.1  reinoud asc_dmafinish (void *dma_h, bus_dma_tag_t dma_t, struct sbic_acb *acb)
    331   1.1  reinoud {
    332   1.1  reinoud 	printf("asc_dmafinish\n");
    333   1.1  reinoud }
    334   1.1  reinoud 
    335   1.1  reinoud void
    336   1.1  reinoud asc_dump(void)
    337   1.1  reinoud {
    338   1.1  reinoud 	int i;
    339  1.19      chs 	struct asc_softc *sc;
    340   1.1  reinoud 
    341  1.15   cegger 	for (i = 0; i < asc_cd.cd_ndevs; ++i) {
    342  1.15   cegger 		sc = device_lookup_private(&asc_cd, i);
    343  1.15   cegger 		if (sc != NULL)
    344  1.19      chs 			sbic_dump(&sc->sc_softc);
    345  1.15   cegger 	}
    346   1.1  reinoud }
    347   1.1  reinoud 
    348   1.1  reinoud int
    349   1.1  reinoud asc_intr(void *arg)
    350   1.1  reinoud {
    351   1.1  reinoud 	struct asc_softc *sc = arg;
    352   1.1  reinoud 	int intr;
    353   1.1  reinoud 
    354   1.1  reinoud 	/* printf("ascintr:");*/
    355   1.1  reinoud        	intr = ReadByte(sc->sc_intstat);
    356   1.1  reinoud 	/* printf("%02x\n", intr);*/
    357   1.1  reinoud 
    358   1.1  reinoud 	if (intr & IS_SBIC_IRQ)
    359   1.1  reinoud 		sbicintr((struct sbic_softc *)sc);
    360   1.1  reinoud 
    361   1.1  reinoud 	return 0;	/* Pass interrupt on down the chain */
    362   1.1  reinoud }
    363   1.1  reinoud 
    364   1.1  reinoud /*
    365   1.1  reinoud  * limit the transfer as required.
    366   1.1  reinoud  */
    367   1.1  reinoud void
    368   1.1  reinoud asc_minphys(struct buf *bp)
    369   1.1  reinoud {
    370   1.1  reinoud #if 0
    371   1.1  reinoud 	/*
    372   1.1  reinoud 	 * We must limit the DMA xfer size
    373   1.1  reinoud 	 */
    374   1.1  reinoud 	if (bp->b_bcount > MAX_DMA_LEN) {
    375  1.12      wiz 		printf("asc: Reducing DMA length\n");
    376   1.1  reinoud 		bp->b_bcount = MAX_DMA_LEN;
    377   1.1  reinoud 	}
    378   1.1  reinoud #endif
    379   1.1  reinoud 	minphys(bp);
    380   1.1  reinoud }
    381