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hcsc.c revision 1.7.2.3
      1  1.7.2.3  jdolecek /*	$NetBSD: hcsc.c,v 1.7.2.3 2002/10/10 18:41:34 jdolecek Exp $	*/
      2      1.1     bjh21 
      3      1.1     bjh21 /*
      4      1.2     bjh21  * Copyright (c) 2001 Ben Harris
      5      1.1     bjh21  * Copyright (c) 1998 The NetBSD Foundation, Inc.
      6      1.1     bjh21  * All rights reserved.
      7      1.1     bjh21  *
      8      1.1     bjh21  * This code is derived from software contributed to The NetBSD Foundation
      9      1.1     bjh21  * by Mark Brinicombe of Causality Limited.
     10      1.1     bjh21  *
     11      1.1     bjh21  * Redistribution and use in source and binary forms, with or without
     12      1.1     bjh21  * modification, are permitted provided that the following conditions
     13      1.1     bjh21  * are met:
     14      1.1     bjh21  * 1. Redistributions of source code must retain the above copyright
     15      1.1     bjh21  *    notice, this list of conditions and the following disclaimer.
     16      1.1     bjh21  * 2. Redistributions in binary form must reproduce the above copyright
     17      1.1     bjh21  *    notice, this list of conditions and the following disclaimer in the
     18      1.1     bjh21  *    documentation and/or other materials provided with the distribution.
     19      1.1     bjh21  * 3. All advertising materials mentioning features or use of this software
     20      1.1     bjh21  *    must display the following acknowledgement:
     21      1.1     bjh21  *	This product includes software developed by the NetBSD
     22      1.1     bjh21  *	Foundation, Inc. and its contributors.
     23      1.1     bjh21  * 4. Neither the name of The NetBSD Foundation nor the names of its
     24      1.1     bjh21  *    contributors may be used to endorse or promote products derived
     25      1.1     bjh21  *    from this software without specific prior written permission.
     26      1.1     bjh21  *
     27      1.1     bjh21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     28      1.1     bjh21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     29      1.1     bjh21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     30      1.1     bjh21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     31      1.1     bjh21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     32      1.1     bjh21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     33      1.1     bjh21  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     34      1.1     bjh21  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     35      1.1     bjh21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     36      1.1     bjh21  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     37      1.1     bjh21  * POSSIBILITY OF SUCH DAMAGE.
     38      1.1     bjh21  */
     39      1.2     bjh21 /*
     40      1.2     bjh21  * Copyright (c) 1996, 1997 Matthias Pfaller.
     41      1.2     bjh21  * All rights reserved.
     42      1.2     bjh21  *
     43      1.2     bjh21  * Redistribution and use in source and binary forms, with or without
     44      1.2     bjh21  * modification, are permitted provided that the following conditions
     45      1.2     bjh21  * are met:
     46      1.2     bjh21  * 1. Redistributions of source code must retain the above copyright
     47      1.2     bjh21  *    notice, this list of conditions and the following disclaimer.
     48      1.2     bjh21  * 2. Redistributions in binary form must reproduce the above copyright
     49      1.2     bjh21  *    notice, this list of conditions and the following disclaimer in the
     50      1.2     bjh21  *    documentation and/or other materials provided with the distribution.
     51      1.2     bjh21  * 3. All advertising materials mentioning features or use of this software
     52      1.2     bjh21  *    must display the following acknowledgement:
     53      1.2     bjh21  *	This product includes software developed by Matthias Pfaller.
     54      1.2     bjh21  * 4. The name of the author may not be used to endorse or promote products
     55      1.2     bjh21  *    derived from this software without specific prior written permission
     56      1.2     bjh21  *
     57      1.2     bjh21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     58      1.2     bjh21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     59      1.2     bjh21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     60      1.2     bjh21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     61      1.2     bjh21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     62      1.2     bjh21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     63      1.2     bjh21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     64      1.2     bjh21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     65      1.2     bjh21  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     66      1.2     bjh21  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     67      1.2     bjh21  */
     68      1.1     bjh21 
     69      1.1     bjh21 /*
     70      1.1     bjh21  * HCCS 8-bit SCSI driver using the generic NCR5380 driver
     71      1.6     bjh21  *
     72      1.6     bjh21  * Andy Armstrong gives some details of the HCCS SCSI cards at
     73      1.6     bjh21  * <URL:http://www.armlinux.org/~webmail/linux-arm/1997-08/msg00042.html>.
     74      1.1     bjh21  */
     75      1.1     bjh21 
     76  1.7.2.1   thorpej #include <sys/cdefs.h>
     77  1.7.2.3  jdolecek __KERNEL_RCSID(0, "$NetBSD: hcsc.c,v 1.7.2.3 2002/10/10 18:41:34 jdolecek Exp $");
     78      1.1     bjh21 
     79  1.7.2.1   thorpej #include <sys/param.h>
     80      1.1     bjh21 
     81      1.1     bjh21 #include <sys/systm.h>
     82      1.1     bjh21 #include <sys/kernel.h>
     83      1.1     bjh21 #include <sys/device.h>
     84      1.1     bjh21 #include <sys/buf.h>
     85      1.1     bjh21 #include <dev/scsipi/scsi_all.h>
     86      1.1     bjh21 #include <dev/scsipi/scsipi_all.h>
     87      1.1     bjh21 #include <dev/scsipi/scsiconf.h>
     88      1.1     bjh21 
     89      1.1     bjh21 #include <dev/ic/ncr5380reg.h>
     90      1.1     bjh21 #include <dev/ic/ncr5380var.h>
     91      1.1     bjh21 
     92      1.1     bjh21 #include <machine/bootconfig.h>
     93      1.1     bjh21 
     94      1.1     bjh21 #include <dev/podulebus/podulebus.h>
     95      1.1     bjh21 #include <dev/podulebus/podules.h>
     96      1.7     bjh21 #include <dev/podulebus/powerromreg.h>
     97      1.1     bjh21 
     98      1.5     bjh21 #include <dev/podulebus/hcscreg.h>
     99      1.5     bjh21 
    100      1.1     bjh21 void hcsc_attach (struct device *, struct device *, void *);
    101      1.1     bjh21 int  hcsc_match  (struct device *, struct cfdata *, void *);
    102      1.1     bjh21 
    103      1.2     bjh21 static int hcsc_pdma_in(struct ncr5380_softc *, int, int, u_char *);
    104      1.2     bjh21 static int hcsc_pdma_out(struct ncr5380_softc *, int, int, u_char *);
    105      1.2     bjh21 
    106      1.2     bjh21 
    107      1.1     bjh21 /*
    108      1.1     bjh21  * HCCS 8-bit SCSI softc structure.
    109      1.1     bjh21  *
    110      1.1     bjh21  * Contains the generic ncr5380 device node, podule information and
    111      1.1     bjh21  * global information required by the driver.
    112      1.1     bjh21  */
    113      1.1     bjh21 
    114      1.1     bjh21 struct hcsc_softc {
    115      1.1     bjh21 	struct ncr5380_softc	sc_ncr5380;
    116      1.2     bjh21 	bus_space_tag_t		sc_pdmat;
    117      1.2     bjh21 	bus_space_handle_t	sc_pdmah;
    118      1.1     bjh21 	void		*sc_ih;
    119      1.1     bjh21 	struct evcnt	sc_intrcnt;
    120      1.1     bjh21 };
    121      1.1     bjh21 
    122  1.7.2.3  jdolecek CFATTACH_DECL(hcsc, sizeof(struct hcsc_softc),
    123  1.7.2.3  jdolecek     hcsc_match, hcsc_attach, NULL, NULL);
    124      1.1     bjh21 
    125      1.1     bjh21 /*
    126      1.1     bjh21  * Card probe function
    127      1.1     bjh21  *
    128      1.1     bjh21  * Just match the manufacturer and podule ID's
    129      1.1     bjh21  */
    130      1.1     bjh21 
    131      1.1     bjh21 int
    132      1.1     bjh21 hcsc_match(struct device *parent, struct cfdata *cf, void *aux)
    133      1.1     bjh21 {
    134      1.1     bjh21 	struct podulebus_attach_args *pa = aux;
    135      1.1     bjh21 
    136      1.7     bjh21 	/* Normal ROM */
    137      1.4     bjh21 	if (pa->pa_product == PODULE_HCCS_IDESCSI &&
    138      1.4     bjh21 	    strncmp(pa->pa_descr, "SCSI", 4) == 0)
    139      1.7     bjh21 		return 1;
    140      1.7     bjh21 	/* PowerROM */
    141      1.7     bjh21 	if (pa->pa_product == PODULE_ALSYSTEMS_SCSI &&
    142      1.7     bjh21 	    podulebus_initloader(pa) == 0 &&
    143      1.7     bjh21 	    podloader_callloader(pa, 0, 0) == PRID_HCCS_SCSI1)
    144      1.4     bjh21 		return 1;
    145      1.4     bjh21 	return 0;
    146      1.1     bjh21 }
    147      1.1     bjh21 
    148      1.1     bjh21 /*
    149      1.1     bjh21  * Card attach function
    150      1.1     bjh21  *
    151      1.1     bjh21  */
    152      1.1     bjh21 
    153      1.1     bjh21 void
    154      1.1     bjh21 hcsc_attach(struct device *parent, struct device *self, void *aux)
    155      1.1     bjh21 {
    156      1.1     bjh21 	struct hcsc_softc *sc = (struct hcsc_softc *)self;
    157      1.1     bjh21 	struct podulebus_attach_args *pa = aux;
    158  1.7.2.2  jdolecek #ifndef NCR5380_USE_BUS_SPACE
    159      1.1     bjh21 	u_char *iobase;
    160  1.7.2.2  jdolecek #endif
    161      1.1     bjh21 	char hi_option[sizeof(sc->sc_ncr5380.sc_dev.dv_xname) + 8];
    162      1.1     bjh21 
    163      1.1     bjh21 	sc->sc_ncr5380.sc_min_dma_len = 0;
    164      1.3     bjh21 	sc->sc_ncr5380.sc_no_disconnect = 0;
    165      1.3     bjh21 	sc->sc_ncr5380.sc_parity_disable = 0;
    166      1.1     bjh21 
    167      1.1     bjh21 	sc->sc_ncr5380.sc_dma_alloc = NULL;
    168      1.1     bjh21 	sc->sc_ncr5380.sc_dma_free = NULL;
    169      1.1     bjh21 	sc->sc_ncr5380.sc_dma_poll = NULL;
    170      1.1     bjh21 	sc->sc_ncr5380.sc_dma_setup = NULL;
    171      1.1     bjh21 	sc->sc_ncr5380.sc_dma_start = NULL;
    172      1.1     bjh21 	sc->sc_ncr5380.sc_dma_eop = NULL;
    173      1.1     bjh21 	sc->sc_ncr5380.sc_dma_stop = NULL;
    174      1.1     bjh21 	sc->sc_ncr5380.sc_intr_on = NULL;
    175      1.1     bjh21 	sc->sc_ncr5380.sc_intr_off = NULL;
    176      1.1     bjh21 
    177      1.1     bjh21 #ifdef NCR5380_USE_BUS_SPACE
    178      1.1     bjh21 	sc->sc_ncr5380.sc_regt = pa->pa_fast_t;
    179      1.5     bjh21 	bus_space_map(sc->sc_ncr5380.sc_regt,
    180      1.5     bjh21 	    pa->pa_fast_base + HCSC_DP8490_OFFSET, 8, 0,
    181      1.1     bjh21 	    &sc->sc_ncr5380.sc_regh);
    182      1.1     bjh21 	sc->sc_ncr5380.sci_r0 = 0;
    183      1.1     bjh21 	sc->sc_ncr5380.sci_r1 = 1;
    184      1.1     bjh21 	sc->sc_ncr5380.sci_r2 = 2;
    185      1.1     bjh21 	sc->sc_ncr5380.sci_r3 = 3;
    186      1.1     bjh21 	sc->sc_ncr5380.sci_r4 = 4;
    187      1.1     bjh21 	sc->sc_ncr5380.sci_r5 = 5;
    188      1.1     bjh21 	sc->sc_ncr5380.sci_r6 = 6;
    189      1.1     bjh21 	sc->sc_ncr5380.sci_r7 = 7;
    190      1.1     bjh21 #else
    191      1.5     bjh21 	iobase = (u_char *)pa->pa_fast_base + HCSC_DP8490_OFFSET;
    192      1.1     bjh21 	sc->sc_ncr5380.sci_r0 = iobase + 0;
    193      1.1     bjh21 	sc->sc_ncr5380.sci_r1 = iobase + 4;
    194      1.1     bjh21 	sc->sc_ncr5380.sci_r2 = iobase + 8;
    195      1.1     bjh21 	sc->sc_ncr5380.sci_r3 = iobase + 12;
    196      1.1     bjh21 	sc->sc_ncr5380.sci_r4 = iobase + 16;
    197      1.1     bjh21 	sc->sc_ncr5380.sci_r5 = iobase + 20;
    198      1.1     bjh21 	sc->sc_ncr5380.sci_r6 = iobase + 24;
    199      1.1     bjh21 	sc->sc_ncr5380.sci_r7 = iobase + 28;
    200      1.1     bjh21 #endif
    201      1.2     bjh21 	sc->sc_pdmat = pa->pa_mod_t;
    202      1.5     bjh21 	bus_space_map(sc->sc_pdmat, pa->pa_mod_base + HCSC_PDMA_OFFSET, 1, 0,
    203      1.5     bjh21 	    &sc->sc_pdmah);
    204      1.1     bjh21 
    205      1.1     bjh21 	sc->sc_ncr5380.sc_rev = NCR_VARIANT_DP8490;
    206      1.1     bjh21 
    207      1.2     bjh21 	sc->sc_ncr5380.sc_pio_in = hcsc_pdma_in;
    208      1.2     bjh21 	sc->sc_ncr5380.sc_pio_out = hcsc_pdma_out;
    209      1.1     bjh21 
    210      1.1     bjh21 	/* Provide an override for the host id */
    211      1.1     bjh21 	sc->sc_ncr5380.sc_channel.chan_id = 7;
    212      1.1     bjh21 	sprintf(hi_option, "%s.hostid", sc->sc_ncr5380.sc_dev.dv_xname);
    213      1.1     bjh21 	(void)get_bootconf_option(boot_args, hi_option,
    214      1.1     bjh21 	    BOOTOPT_TYPE_INT, &sc->sc_ncr5380.sc_channel.chan_id);
    215      1.1     bjh21 	sc->sc_ncr5380.sc_adapter.adapt_minphys = minphys;
    216      1.1     bjh21 
    217      1.2     bjh21 	printf(": host ID %d\n", sc->sc_ncr5380.sc_channel.chan_id);
    218      1.1     bjh21 
    219      1.1     bjh21 	evcnt_attach_dynamic(&sc->sc_intrcnt, EVCNT_TYPE_INTR, NULL,
    220      1.1     bjh21 	    self->dv_xname, "intr");
    221      1.1     bjh21 	sc->sc_ih = podulebus_irq_establish(pa->pa_ih, IPL_BIO, ncr5380_intr,
    222      1.1     bjh21 	    sc, &sc->sc_intrcnt);
    223      1.1     bjh21 
    224      1.1     bjh21 	ncr5380_attach(&sc->sc_ncr5380);
    225      1.2     bjh21 }
    226      1.2     bjh21 
    227      1.2     bjh21 #ifndef HCSC_TSIZE_OUT
    228      1.2     bjh21 #define HCSC_TSIZE_OUT	512
    229      1.2     bjh21 #endif
    230      1.2     bjh21 
    231      1.2     bjh21 #ifndef HCSC_TSIZE_IN
    232      1.2     bjh21 #define HCSC_TSIZE_IN	512
    233      1.2     bjh21 #endif
    234      1.2     bjh21 
    235      1.2     bjh21 #define TIMEOUT 1000000
    236      1.2     bjh21 
    237      1.2     bjh21 static __inline int
    238      1.2     bjh21 hcsc_ready(struct ncr5380_softc *sc)
    239      1.2     bjh21 {
    240      1.2     bjh21 	int i;
    241      1.2     bjh21 
    242      1.2     bjh21 	for (i = TIMEOUT; i > 0; i--) {
    243      1.2     bjh21 		if ((NCR5380_READ(sc,sci_csr) &
    244      1.2     bjh21 		    (SCI_CSR_DREQ | SCI_CSR_PHASE_MATCH)) ==
    245      1.2     bjh21 		    (SCI_CSR_DREQ | SCI_CSR_PHASE_MATCH))
    246      1.2     bjh21 		    	return(1);
    247      1.2     bjh21 
    248      1.2     bjh21 		if ((NCR5380_READ(sc, sci_csr) & SCI_CSR_PHASE_MATCH) == 0 ||
    249      1.2     bjh21 		    SCI_BUSY(sc) == 0)
    250      1.2     bjh21 			return(0);
    251      1.2     bjh21 	}
    252      1.2     bjh21 	printf("%s: ready timeout\n", sc->sc_dev.dv_xname);
    253      1.2     bjh21 	return(0);
    254      1.2     bjh21 }
    255      1.2     bjh21 
    256      1.2     bjh21 
    257      1.2     bjh21 
    258      1.2     bjh21 /* Return zero on success. */
    259      1.2     bjh21 static __inline void hcsc_wait_not_req(struct ncr5380_softc *sc)
    260      1.2     bjh21 {
    261      1.2     bjh21 	int timo;
    262      1.2     bjh21 	for (timo = TIMEOUT; timo; timo--) {
    263      1.2     bjh21 		if ((NCR5380_READ(sc, sci_bus_csr) & SCI_BUS_REQ) == 0 ||
    264      1.2     bjh21 		    (NCR5380_READ(sc, sci_csr) & SCI_CSR_PHASE_MATCH) == 0 ||
    265      1.2     bjh21 		    SCI_BUSY(sc) == 0) {
    266      1.2     bjh21 			return;
    267      1.2     bjh21 		}
    268      1.2     bjh21 	}
    269      1.2     bjh21 	printf("%s: pdma not_req timeout\n", sc->sc_dev.dv_xname);
    270      1.2     bjh21 }
    271      1.2     bjh21 
    272      1.2     bjh21 static int
    273      1.2     bjh21 hcsc_pdma_in(struct ncr5380_softc *ncr_sc, int phase, int datalen,
    274      1.2     bjh21     u_char *data)
    275      1.2     bjh21 {
    276      1.2     bjh21 	struct hcsc_softc *sc = (void *)ncr_sc;
    277      1.2     bjh21 	bus_space_tag_t pdmat = sc->sc_pdmat;
    278      1.2     bjh21 	bus_space_handle_t pdmah = sc->sc_pdmah;
    279      1.2     bjh21 	int s, resid, len;
    280      1.2     bjh21 
    281      1.2     bjh21 	s = splbio();
    282      1.2     bjh21 
    283      1.2     bjh21 	NCR5380_WRITE(ncr_sc, sci_mode,
    284      1.2     bjh21 	    NCR5380_READ(ncr_sc, sci_mode) | SCI_MODE_DMA);
    285      1.2     bjh21 	NCR5380_WRITE(ncr_sc, sci_irecv, 0);
    286      1.2     bjh21 
    287      1.2     bjh21 	resid = datalen;
    288      1.2     bjh21 	while (resid > 0) {
    289      1.2     bjh21 		len = min(resid, HCSC_TSIZE_IN);
    290      1.2     bjh21 		if (hcsc_ready(ncr_sc) == 0)
    291      1.2     bjh21 			goto interrupt;
    292      1.2     bjh21 		bus_space_read_multi_1(pdmat, pdmah, 0, data, len);
    293      1.2     bjh21 		data += len;
    294      1.2     bjh21 		resid -= len;
    295      1.2     bjh21 	}
    296      1.2     bjh21 
    297      1.2     bjh21 	hcsc_wait_not_req(ncr_sc);
    298      1.2     bjh21 
    299      1.2     bjh21 interrupt:
    300      1.2     bjh21 	SCI_CLR_INTR(ncr_sc);
    301      1.2     bjh21 	NCR5380_WRITE(ncr_sc, sci_mode,
    302      1.2     bjh21 	    NCR5380_READ(ncr_sc, sci_mode) & ~SCI_MODE_DMA);
    303      1.2     bjh21 	splx(s);
    304      1.2     bjh21 	return datalen - resid;
    305      1.2     bjh21 }
    306      1.2     bjh21 
    307      1.2     bjh21 static int
    308      1.2     bjh21 hcsc_pdma_out(struct ncr5380_softc *ncr_sc, int phase, int datalen,
    309      1.2     bjh21     u_char *data)
    310      1.2     bjh21 {
    311      1.2     bjh21 	struct hcsc_softc *sc = (void *)ncr_sc;
    312      1.2     bjh21 	bus_space_tag_t pdmat = sc->sc_pdmat;
    313      1.2     bjh21 	bus_space_handle_t pdmah = sc->sc_pdmah;
    314      1.2     bjh21 	int i, s, icmd, resid;
    315      1.2     bjh21 
    316      1.2     bjh21 	s = splbio();
    317      1.2     bjh21 	icmd = NCR5380_READ(ncr_sc, sci_icmd) & SCI_ICMD_RMASK;
    318      1.2     bjh21 	NCR5380_WRITE(ncr_sc, sci_icmd, icmd | SCI_ICMD_DATA);
    319      1.2     bjh21 	NCR5380_WRITE(ncr_sc, sci_mode,
    320      1.2     bjh21 	    NCR5380_READ(ncr_sc, sci_mode) | SCI_MODE_DMA);
    321      1.2     bjh21 	NCR5380_WRITE(ncr_sc, sci_dma_send, 0);
    322      1.2     bjh21 
    323      1.2     bjh21 	resid = datalen;
    324      1.2     bjh21 	if (hcsc_ready(ncr_sc) == 0)
    325      1.2     bjh21 		goto interrupt;
    326      1.2     bjh21 
    327      1.2     bjh21 	if (resid > HCSC_TSIZE_OUT) {
    328      1.2     bjh21 		/*
    329      1.2     bjh21 		 * Because of the chips DMA prefetch, phase changes
    330      1.2     bjh21 		 * etc, won't be detected until we have written at
    331      1.2     bjh21 		 * least one byte more. We pre-write 4 bytes so
    332      1.2     bjh21 		 * subsequent transfers will be aligned to a 4 byte
    333      1.2     bjh21 		 * boundary. Assuming disconects will only occur on
    334      1.2     bjh21 		 * block boundaries, we then correct for the pre-write
    335      1.2     bjh21 		 * when and if we get a phase change. If the chip had
    336      1.2     bjh21 		 * DMA byte counting hardware, the assumption would not
    337      1.2     bjh21 		 * be necessary.
    338      1.2     bjh21 		 */
    339      1.2     bjh21 		bus_space_write_multi_1(pdmat, pdmah, 0, data, 4);
    340      1.2     bjh21 		data += 4;
    341      1.2     bjh21 		resid -= 4;
    342      1.2     bjh21 
    343      1.2     bjh21 		for (; resid >= HCSC_TSIZE_OUT; resid -= HCSC_TSIZE_OUT) {
    344      1.2     bjh21 			if (hcsc_ready(ncr_sc) == 0) {
    345      1.2     bjh21 				resid += 4; /* Overshot */
    346      1.2     bjh21 				goto interrupt;
    347      1.2     bjh21 			}
    348      1.2     bjh21 			bus_space_write_multi_1(pdmat, pdmah, 0, data,
    349      1.2     bjh21 			    HCSC_TSIZE_OUT);
    350      1.2     bjh21 			data += HCSC_TSIZE_OUT;
    351      1.2     bjh21 		}
    352      1.2     bjh21 		if (hcsc_ready(ncr_sc) == 0) {
    353      1.2     bjh21 			resid += 4; /* Overshot */
    354      1.2     bjh21 			goto interrupt;
    355      1.2     bjh21 		}
    356      1.2     bjh21 	}
    357      1.2     bjh21 
    358      1.2     bjh21 	if (resid) {
    359      1.2     bjh21 		bus_space_write_multi_1(pdmat, pdmah, 0, data, resid);
    360      1.2     bjh21 		resid = 0;
    361      1.2     bjh21 	}
    362      1.2     bjh21 	for (i = TIMEOUT; i > 0; i--) {
    363      1.2     bjh21 		if ((NCR5380_READ(ncr_sc, sci_csr)
    364      1.2     bjh21 		    & (SCI_CSR_DREQ|SCI_CSR_PHASE_MATCH))
    365      1.2     bjh21 		    != SCI_CSR_DREQ)
    366      1.2     bjh21 			break;
    367      1.2     bjh21 	}
    368      1.2     bjh21 	if (i != 0)
    369      1.2     bjh21 		bus_space_write_1(pdmat, pdmah, 0, 0);
    370      1.2     bjh21 	else
    371      1.2     bjh21 		printf("%s: timeout waiting for final SCI_DSR_DREQ.\n",
    372      1.2     bjh21 			ncr_sc->sc_dev.dv_xname);
    373      1.2     bjh21 
    374      1.2     bjh21 	hcsc_wait_not_req(ncr_sc);
    375      1.2     bjh21 interrupt:
    376      1.2     bjh21 	SCI_CLR_INTR(ncr_sc);
    377      1.2     bjh21 	NCR5380_WRITE(ncr_sc, sci_mode,
    378      1.2     bjh21 	    NCR5380_READ(ncr_sc, sci_mode) & ~SCI_MODE_DMA);
    379      1.2     bjh21 	NCR5380_WRITE(ncr_sc, sci_icmd, icmd);
    380      1.2     bjh21 	splx(s);
    381      1.2     bjh21 	return(datalen - resid);
    382      1.1     bjh21 }
    383