xref: /freebsd-11-stable/sys/dev/esp/esp_sbus.c

/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD AND BSD-2-Clause-NetBSD
 *
 * Copyright (c) 2004 Scott Long
 * Copyright (c) 2005 Marius Strobl <marius@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

/*	$NetBSD: esp_sbus.c,v 1.51 2009/09/17 16:28:12 tsutsui Exp $	*/

/*-
 * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles M. Hannum; Jason R. Thorpe of the Numerical Aerospace
 * Simulation Facility, NASA Ames Research Center; Paul Kranenburg.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: stable/11/sys/dev/esp/esp_sbus.c 330897 2018-03-14 03:19:51Z eadler $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/rman.h>

#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/openfirm.h>
#include <machine/bus.h>
#include <machine/ofw_machdep.h>
#include <machine/resource.h>

#include <cam/cam.h>
#include <cam/cam_ccb.h>
#include <cam/scsi/scsi_all.h>
#include <cam/scsi/scsi_message.h>

#include <sparc64/sbus/lsi64854reg.h>
#include <sparc64/sbus/lsi64854var.h>
#include <sparc64/sbus/sbusvar.h>

#include <dev/esp/ncr53c9xreg.h>
#include <dev/esp/ncr53c9xvar.h>

/* #define ESP_SBUS_DEBUG */

struct esp_softc {
	struct ncr53c9x_softc	sc_ncr53c9x;	/* glue to MI code */
	device_t		sc_dev;

	struct resource		*sc_res;

	struct resource		*sc_irqres;
	void			*sc_irq;

	struct lsi64854_softc	*sc_dma;	/* pointer to my DMA */
};

static int	esp_probe(device_t);
static int	esp_dma_attach(device_t);
static int	esp_dma_detach(device_t);
static int	esp_sbus_attach(device_t);
static int	esp_sbus_detach(device_t);
static int	esp_suspend(device_t);
static int	esp_resume(device_t);

static device_method_t esp_dma_methods[] = {
	DEVMETHOD(device_probe,		esp_probe),
	DEVMETHOD(device_attach,	esp_dma_attach),
	DEVMETHOD(device_detach,	esp_dma_detach),
	DEVMETHOD(device_suspend,	esp_suspend),
	DEVMETHOD(device_resume,	esp_resume),

	DEVMETHOD_END
};

static driver_t esp_dma_driver = {
	"esp",
	esp_dma_methods,
	sizeof(struct esp_softc)
};

DRIVER_MODULE(esp, dma, esp_dma_driver, esp_devclass, 0, 0);
MODULE_DEPEND(esp, dma, 1, 1, 1);

static device_method_t esp_sbus_methods[] = {
	DEVMETHOD(device_probe,		esp_probe),
	DEVMETHOD(device_attach,	esp_sbus_attach),
	DEVMETHOD(device_detach,	esp_sbus_detach),
	DEVMETHOD(device_suspend,	esp_suspend),
	DEVMETHOD(device_resume,	esp_resume),

	DEVMETHOD_END
};

static driver_t esp_sbus_driver = {
	"esp",
	esp_sbus_methods,
	sizeof(struct esp_softc)
};

DRIVER_MODULE(esp, sbus, esp_sbus_driver, esp_devclass, 0, 0);
MODULE_DEPEND(esp, sbus, 1, 1, 1);

/*
 * Functions and the switch for the MI code
 */
static uint8_t	esp_read_reg(struct ncr53c9x_softc *sc, int reg);
static void	esp_write_reg(struct ncr53c9x_softc *sc, int reg, uint8_t v);
static int	esp_dma_isintr(struct ncr53c9x_softc *sc);
static void	esp_dma_reset(struct ncr53c9x_softc *sc);
static int	esp_dma_intr(struct ncr53c9x_softc *sc);
static int	esp_dma_setup(struct ncr53c9x_softc *sc, void **addr,
		    size_t *len, int datain, size_t *dmasize);
static void	esp_dma_go(struct ncr53c9x_softc *sc);
static void	esp_dma_stop(struct ncr53c9x_softc *sc);
static int	esp_dma_isactive(struct ncr53c9x_softc *sc);
static int	espattach(struct esp_softc *esc,
		    const struct ncr53c9x_glue *gluep);
static int	espdetach(struct esp_softc *esc);

static const struct ncr53c9x_glue esp_sbus_glue = {
	esp_read_reg,
	esp_write_reg,
	esp_dma_isintr,
	esp_dma_reset,
	esp_dma_intr,
	esp_dma_setup,
	esp_dma_go,
	esp_dma_stop,
	esp_dma_isactive,
};

static int
esp_probe(device_t dev)
{
	const char *name;

	name = ofw_bus_get_name(dev);
	if (strcmp("SUNW,fas", name) == 0) {
		device_set_desc(dev, "Sun FAS366 Fast-Wide SCSI");
	        return (BUS_PROBE_DEFAULT);
	} else if (strcmp("esp", name) == 0) {
		device_set_desc(dev, "Sun ESP SCSI/Sun FAS Fast-SCSI");
	        return (BUS_PROBE_DEFAULT);
	}

	return (ENXIO);
}

static int
esp_sbus_attach(device_t dev)
{
	struct esp_softc *esc;
	struct ncr53c9x_softc *sc;
	struct lsi64854_softc *lsc;
	device_t *children;
	int error, i, nchildren;

	esc = device_get_softc(dev);
	sc = &esc->sc_ncr53c9x;

	lsc = NULL;
	esc->sc_dev = dev;
	sc->sc_freq = sbus_get_clockfreq(dev);

	if (strcmp(ofw_bus_get_name(dev), "SUNW,fas") == 0) {
		/*
		 * Allocate space for DMA, in SUNW,fas there are no
		 * separate DMA devices.
		 */
		lsc = malloc(sizeof (struct lsi64854_softc), M_DEVBUF,
		    M_NOWAIT | M_ZERO);
		if (lsc == NULL) {
			device_printf(dev, "out of memory (lsi64854_softc)\n");
			return (ENOMEM);
		}
		esc->sc_dma = lsc;

		/*
		 * SUNW,fas have 2 register spaces: DMA (lsi64854) and
		 * SCSI core (ncr53c9x).
		 */

		/* Allocate DMA registers. */
		i = 0;
		if ((lsc->sc_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
		    &i, RF_ACTIVE)) == NULL) {
			device_printf(dev, "cannot allocate DMA registers\n");
			error = ENXIO;
			goto fail_sbus_lsc;
		}

		/* Create a parent DMA tag based on this bus. */
		error = bus_dma_tag_create(
		    bus_get_dma_tag(dev),	/* parent */
		    1, 0,			/* alignment, boundary */
		    BUS_SPACE_MAXADDR,		/* lowaddr */
		    BUS_SPACE_MAXADDR,		/* highaddr */
		    NULL, NULL,			/* filter, filterarg */
		    BUS_SPACE_MAXSIZE,		/* maxsize */
		    BUS_SPACE_UNRESTRICTED,	/* nsegments */
		    BUS_SPACE_MAXSIZE,		/* maxsegsize */
		    0,				/* flags */
		    NULL, NULL,			/* no locking */
		    &lsc->sc_parent_dmat);
		if (error != 0) {
			device_printf(dev, "cannot allocate parent DMA tag\n");
			goto fail_sbus_lres;
		}

		i = sbus_get_burstsz(dev);

#ifdef ESP_SBUS_DEBUG
		printf("%s: burst 0x%x\n", __func__, i);
#endif

		lsc->sc_burst = (i & SBUS_BURST_32) ? 32 :
		    (i & SBUS_BURST_16) ? 16 : 0;

		lsc->sc_channel = L64854_CHANNEL_SCSI;
		lsc->sc_client = sc;
		lsc->sc_dev = dev;

		/*
		 * Allocate SCSI core registers.
		 */
		i = 1;
		if ((esc->sc_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
		    &i, RF_ACTIVE)) == NULL) {
			device_printf(dev,
			    "cannot allocate SCSI core registers\n");
			error = ENXIO;
			goto fail_sbus_lpdma;
		}
	} else {
		/*
		 * Search accompanying DMA engine.  It should have been
		 * already attached otherwise there isn't much we can do.
		 */
		if (device_get_children(device_get_parent(dev), &children,
		    &nchildren) != 0) {
			device_printf(dev, "cannot determine siblings\n");
			return (ENXIO);
		}
		for (i = 0; i < nchildren; i++) {
			if (device_is_attached(children[i]) &&
			    sbus_get_slot(children[i]) ==
			    sbus_get_slot(dev) &&
			    strcmp(ofw_bus_get_name(children[i]),
			    "dma") == 0) {
				/* XXX hackery */
				esc->sc_dma = (struct lsi64854_softc *)
				    device_get_softc(children[i]);
				break;
			}
		}
		free(children, M_TEMP);
		if (esc->sc_dma == NULL) {
			device_printf(dev, "cannot find DMA engine\n");
			return (ENXIO);
		}
		esc->sc_dma->sc_client = sc;

		/*
		 * Allocate SCSI core registers.
		 */
		i = 0;
		if ((esc->sc_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
		    &i, RF_ACTIVE)) == NULL) {
			device_printf(dev,
			    "cannot allocate SCSI core registers\n");
			return (ENXIO);
		}
	}

	error = espattach(esc, &esp_sbus_glue);
	if (error != 0) {
		device_printf(dev, "espattach failed\n");
		goto fail_sbus_eres;
	}

	return (0);

 fail_sbus_eres:
	bus_release_resource(dev, SYS_RES_MEMORY, rman_get_rid(esc->sc_res),
	    esc->sc_res);
	if (strcmp(ofw_bus_get_name(dev), "SUNW,fas") != 0)
		return (error);
 fail_sbus_lpdma:
	bus_dma_tag_destroy(lsc->sc_parent_dmat);
 fail_sbus_lres:
	bus_release_resource(dev, SYS_RES_MEMORY, rman_get_rid(lsc->sc_res),
	    lsc->sc_res);
 fail_sbus_lsc:
	free(lsc, M_DEVBUF);
	return (error);
}

static int
esp_sbus_detach(device_t dev)
{
	struct esp_softc *esc;
	struct lsi64854_softc *lsc;
	int error;

	esc = device_get_softc(dev);
	lsc = esc->sc_dma;

	error = espdetach(esc);
	if (error != 0)
		return (error);
	bus_release_resource(dev, SYS_RES_MEMORY, rman_get_rid(esc->sc_res),
		esc->sc_res);
	if (strcmp(ofw_bus_get_name(dev), "SUNW,fas") != 0)
		return (0);
	bus_dma_tag_destroy(lsc->sc_parent_dmat);
	bus_release_resource(dev, SYS_RES_MEMORY, rman_get_rid(lsc->sc_res),
	    lsc->sc_res);
	free(lsc, M_DEVBUF);

	return (0);
}

static int
esp_dma_attach(device_t dev)
{
	struct esp_softc *esc;
	struct ncr53c9x_softc *sc;
	int error, i;

	esc = device_get_softc(dev);
	sc = &esc->sc_ncr53c9x;

	esc->sc_dev = dev;
	if (OF_getprop(ofw_bus_get_node(dev), "clock-frequency",
	    &sc->sc_freq, sizeof(sc->sc_freq)) == -1) {
		printf("failed to query OFW for clock-frequency\n");
		return (ENXIO);
	}

	/* XXX hackery */
	esc->sc_dma = (struct lsi64854_softc *)
	    device_get_softc(device_get_parent(dev));
	esc->sc_dma->sc_client = sc;

	/*
	 * Allocate SCSI core registers.
	 */
	i = 0;
	if ((esc->sc_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
	    &i, RF_ACTIVE)) == NULL) {
		device_printf(dev, "cannot allocate SCSI core registers\n");
		return (ENXIO);
	}

	error = espattach(esc, &esp_sbus_glue);
	if (error != 0) {
		device_printf(dev, "espattach failed\n");
		goto fail_dma_eres;
	}

	return (0);

 fail_dma_eres:
	bus_release_resource(dev, SYS_RES_MEMORY, rman_get_rid(esc->sc_res),
	    esc->sc_res);
	return (error);
}

static int
esp_dma_detach(device_t dev)
{
	struct esp_softc *esc;
	int error;

	esc = device_get_softc(dev);

	error = espdetach(esc);
	if (error != 0)
		return (error);
	bus_release_resource(dev, SYS_RES_MEMORY, rman_get_rid(esc->sc_res),
	    esc->sc_res);

	return (0);
}

static int
esp_suspend(device_t dev)
{

	return (ENXIO);
}

static int
esp_resume(device_t dev)
{

	return (ENXIO);
}

static int
espattach(struct esp_softc *esc, const struct ncr53c9x_glue *gluep)
{
	struct ncr53c9x_softc *sc = &esc->sc_ncr53c9x;
	unsigned int uid = 0;
	int error, i;

	NCR_LOCK_INIT(sc);

	sc->sc_id = OF_getscsinitid(esc->sc_dev);

#ifdef ESP_SBUS_DEBUG
	device_printf(esc->sc_dev, "%s: sc_id %d, freq %d\n",
	    __func__, sc->sc_id, sc->sc_freq);
#endif

	/*
	 * The `ESC' DMA chip must be reset before we can access
	 * the ESP registers.
	 */
	if (esc->sc_dma->sc_rev == DMAREV_ESC)
		DMA_RESET(esc->sc_dma);

	/*
	 * Set up glue for MI code early; we use some of it here.
	 */
	sc->sc_glue = gluep;

	/* gimme MHz */
	sc->sc_freq /= 1000000;

	/*
	 * XXX More of this should be in ncr53c9x_attach(), but
	 * XXX should we really poke around the chip that much in
	 * XXX the MI code?  Think about this more...
	 */

	/*
	 * Read the part-unique ID code of the SCSI chip.  The contained
	 * value is only valid if all of the following conditions are met:
	 * - After power-up or chip reset.
	 * - Before any value is written to this register.
	 * - The NCRCFG2_FE bit is set.
	 * - A (NCRCMD_NOP | NCRCMD_DMA) command has been issued.
	 */
	NCRCMD(sc, NCRCMD_RSTCHIP);
	NCRCMD(sc, NCRCMD_NOP);
	sc->sc_cfg2 = NCRCFG2_FE;
	NCR_WRITE_REG(sc, NCR_CFG2, sc->sc_cfg2);
	NCRCMD(sc, NCRCMD_NOP | NCRCMD_DMA);
	uid = NCR_READ_REG(sc, NCR_UID);

	/*
	 * It is necessary to try to load the 2nd config register here,
	 * to find out what rev the esp chip is, else the ncr53c9x_reset
	 * will not set up the defaults correctly.
	 */
	sc->sc_cfg1 = sc->sc_id | NCRCFG1_PARENB;
	NCR_WRITE_REG(sc, NCR_CFG1, sc->sc_cfg1);
	sc->sc_cfg2 = 0;
	NCR_WRITE_REG(sc, NCR_CFG2, sc->sc_cfg2);
	sc->sc_cfg2 = NCRCFG2_SCSI2 | NCRCFG2_RPE;
	NCR_WRITE_REG(sc, NCR_CFG2, sc->sc_cfg2);

	if ((NCR_READ_REG(sc, NCR_CFG2) & ~NCRCFG2_RSVD) !=
	    (NCRCFG2_SCSI2 | NCRCFG2_RPE))
		sc->sc_rev = NCR_VARIANT_ESP100;
	else {
		sc->sc_cfg2 = NCRCFG2_SCSI2;
		NCR_WRITE_REG(sc, NCR_CFG2, sc->sc_cfg2);
		sc->sc_cfg3 = 0;
		NCR_WRITE_REG(sc, NCR_CFG3, sc->sc_cfg3);
		sc->sc_cfg3 = (NCRCFG3_CDB | NCRCFG3_FCLK);
		NCR_WRITE_REG(sc, NCR_CFG3, sc->sc_cfg3);
		if (NCR_READ_REG(sc, NCR_CFG3) !=
		    (NCRCFG3_CDB | NCRCFG3_FCLK))
			sc->sc_rev = NCR_VARIANT_ESP100A;
		else {
			/* NCRCFG2_FE enables > 64K transfers. */
			sc->sc_cfg2 |= NCRCFG2_FE;
			sc->sc_cfg3 = 0;
			NCR_WRITE_REG(sc, NCR_CFG3, sc->sc_cfg3);
			if (sc->sc_freq <= 25)
				sc->sc_rev = NCR_VARIANT_ESP200;
			else {
				switch ((uid & 0xf8) >> 3) {
				case 0x00:
					sc->sc_rev = NCR_VARIANT_FAS100A;
					break;

				case 0x02:
					if ((uid & 0x07) == 0x02)
						sc->sc_rev =
						    NCR_VARIANT_FAS216;
					else
						sc->sc_rev =
						    NCR_VARIANT_FAS236;
					break;

				case 0x0a:
					sc->sc_rev = NCR_VARIANT_FAS366;
					break;

				default:
					/*
					 * We could just treat unknown chips
					 * as ESP200 but then we would most
					 * likely drive them out of specs.
					 */
					device_printf(esc->sc_dev,
					    "Unknown chip\n");
					error = ENXIO;
					goto fail_lock;
				}
			}
		}
	}

#ifdef ESP_SBUS_DEBUG
	printf("%s: revision %d, uid 0x%x\n", __func__, sc->sc_rev, uid);
#endif

	/*
	 * This is the value used to start sync negotiations
	 * Note that the NCR register "SYNCTP" is programmed
	 * in "clocks per byte", and has a minimum value of 4.
	 * The SCSI period used in negotiation is one-fourth
	 * of the time (in nanoseconds) needed to transfer one byte.
	 * Since the chip's clock is given in MHz, we have the following
	 * formula: 4 * period = (1000 / freq) * 4
	 */
	sc->sc_minsync = 1000 / sc->sc_freq;

	/*
	 * Except for some variants the maximum transfer size is 64k.
	 */
	sc->sc_maxxfer = 64 * 1024;
	sc->sc_maxoffset = 15;
	sc->sc_extended_geom = 1;

	/*
	 * Alas, we must now modify the value a bit, because it's
	 * only valid when we can switch on FASTCLK and FASTSCSI bits
	 * in the config register 3...
	 */
	switch (sc->sc_rev) {
	case NCR_VARIANT_ESP100:
		sc->sc_maxwidth = MSG_EXT_WDTR_BUS_8_BIT;
		sc->sc_minsync = 0;	/* No synch on old chip? */
		break;

	case NCR_VARIANT_ESP100A:
	case NCR_VARIANT_ESP200:
		sc->sc_maxwidth = MSG_EXT_WDTR_BUS_8_BIT;
		/* Min clocks/byte is 5 */
		sc->sc_minsync = ncr53c9x_cpb2stp(sc, 5);
		break;

	case NCR_VARIANT_FAS100A:
	case NCR_VARIANT_FAS216:
	case NCR_VARIANT_FAS236:
		/*
		 * The onboard SCSI chips in Sun Ultra 1 are actually
		 * documented to be NCR53C9X which use NCRCFG3_FCLK and
		 * NCRCFG3_FSCSI.  BSD/OS however probes these chips as
		 * FAS100A and uses NCRF9XCFG3_FCLK and NCRF9XCFG3_FSCSI
		 * instead which seems to be correct as otherwise sync
		 * negotiation just doesn't work.  Using NCRF9XCFG3_FCLK
		 * and NCRF9XCFG3_FSCSI with these chips in fact also
		 * yields Fast-SCSI speed.
		 */
		sc->sc_features = NCR_F_FASTSCSI;
		sc->sc_cfg3 = NCRF9XCFG3_FCLK;
		sc->sc_cfg3_fscsi = NCRF9XCFG3_FSCSI;
		sc->sc_maxwidth = MSG_EXT_WDTR_BUS_8_BIT;
		sc->sc_maxxfer = 16 * 1024 * 1024;
		break;

	case NCR_VARIANT_FAS366:
		sc->sc_maxwidth = MSG_EXT_WDTR_BUS_16_BIT;
		sc->sc_maxxfer = 16 * 1024 * 1024;
		break;
	}

	/*
	 * Given that we allocate resources based on sc->sc_maxxfer it doesn't
	 * make sense to supply a value higher than the maximum actually used.
	 */
	sc->sc_maxxfer = min(sc->sc_maxxfer, MAXPHYS);

	/* Attach the DMA engine. */
	error = lsi64854_attach(esc->sc_dma);
	if (error != 0) {
		device_printf(esc->sc_dev, "lsi64854_attach failed\n");
		goto fail_lock;
	}

	/* Establish interrupt channel. */
	i = 0;
	if ((esc->sc_irqres = bus_alloc_resource_any(esc->sc_dev, SYS_RES_IRQ,
	    &i, RF_SHAREABLE|RF_ACTIVE)) == NULL) {
		device_printf(esc->sc_dev, "cannot allocate interrupt\n");
		goto fail_lsi;
	}
	if (bus_setup_intr(esc->sc_dev, esc->sc_irqres,
	    INTR_MPSAFE | INTR_TYPE_CAM, NULL, ncr53c9x_intr, sc,
	    &esc->sc_irq)) {
		device_printf(esc->sc_dev, "cannot set up interrupt\n");
		error = ENXIO;
		goto fail_ires;
	}

	/* Turn on target selection using the `DMA' method. */
	if (sc->sc_rev != NCR_VARIANT_FAS366)
		sc->sc_features |= NCR_F_DMASELECT;

	/* Do the common parts of attachment. */
	sc->sc_dev = esc->sc_dev;
	error = ncr53c9x_attach(sc);
	if (error != 0) {
		device_printf(esc->sc_dev, "ncr53c9x_attach failed\n");
		goto fail_intr;
	}

	return (0);

 fail_intr:
	bus_teardown_intr(esc->sc_dev, esc->sc_irqres, esc->sc_irq);
 fail_ires:
	bus_release_resource(esc->sc_dev, SYS_RES_IRQ,
	    rman_get_rid(esc->sc_irqres), esc->sc_irqres);
 fail_lsi:
	lsi64854_detach(esc->sc_dma);
 fail_lock:
	NCR_LOCK_DESTROY(sc);
	return (error);
}

static int
espdetach(struct esp_softc *esc)
{
	struct ncr53c9x_softc *sc = &esc->sc_ncr53c9x;
	int error;

	bus_teardown_intr(esc->sc_dev, esc->sc_irqres, esc->sc_irq);
	error = ncr53c9x_detach(sc);
	if (error != 0)
		return (error);
	error = lsi64854_detach(esc->sc_dma);
	if (error != 0)
		return (error);
	NCR_LOCK_DESTROY(sc);
	bus_release_resource(esc->sc_dev, SYS_RES_IRQ,
	    rman_get_rid(esc->sc_irqres), esc->sc_irqres);

	return (0);
}

/*
 * Glue functions
 */

#ifdef ESP_SBUS_DEBUG
static int esp_sbus_debug = 0;

static const struct {
	const char *r_name;
	int r_flag;
} const esp__read_regnames [] = {
	{ "TCL", 0},			/* 0/00 */
	{ "TCM", 0},			/* 1/04 */
	{ "FIFO", 0},			/* 2/08 */
	{ "CMD", 0},			/* 3/0c */
	{ "STAT", 0},			/* 4/10 */
	{ "INTR", 0},			/* 5/14 */
	{ "STEP", 0},			/* 6/18 */
	{ "FFLAGS", 1},			/* 7/1c */
	{ "CFG1", 1},			/* 8/20 */
	{ "STAT2", 0},			/* 9/24 */
	{ "CFG4", 1},			/* a/28 */
	{ "CFG2", 1},			/* b/2c */
	{ "CFG3", 1},			/* c/30 */
	{ "-none", 1},			/* d/34 */
	{ "TCH", 1},			/* e/38 */
	{ "TCX", 1},			/* f/3c */
};

static const const struct {
	const char *r_name;
	int r_flag;
} const esp__write_regnames[] = {
	{ "TCL", 1},			/* 0/00 */
	{ "TCM", 1},			/* 1/04 */
	{ "FIFO", 0},			/* 2/08 */
	{ "CMD", 0},			/* 3/0c */
	{ "SELID", 1},			/* 4/10 */
	{ "TIMEOUT", 1},		/* 5/14 */
	{ "SYNCTP", 1},			/* 6/18 */
	{ "SYNCOFF", 1},		/* 7/1c */
	{ "CFG1", 1},			/* 8/20 */
	{ "CCF", 1},			/* 9/24 */
	{ "TEST", 1},			/* a/28 */
	{ "CFG2", 1},			/* b/2c */
	{ "CFG3", 1},			/* c/30 */
	{ "-none", 1},			/* d/34 */
	{ "TCH", 1},			/* e/38 */
	{ "TCX", 1},			/* f/3c */
};
#endif

static uint8_t
esp_read_reg(struct ncr53c9x_softc *sc, int reg)
{
	struct esp_softc *esc = (struct esp_softc *)sc;
	uint8_t v;

	v = bus_read_1(esc->sc_res, reg * 4);

#ifdef ESP_SBUS_DEBUG
	if (esp_sbus_debug && (reg < 0x10) && esp__read_regnames[reg].r_flag)
		printf("RD:%x <%s> %x\n", reg * 4, ((unsigned)reg < 0x10) ?
		    esp__read_regnames[reg].r_name : "<***>", v);
#endif

	return (v);
}

static void
esp_write_reg(struct ncr53c9x_softc *sc, int reg, uint8_t v)
{
	struct esp_softc *esc = (struct esp_softc *)sc;

#ifdef ESP_SBUS_DEBUG
	if (esp_sbus_debug && (reg < 0x10) && esp__write_regnames[reg].r_flag)
		printf("WR:%x <%s> %x\n", reg * 4, ((unsigned)reg < 0x10) ?
		    esp__write_regnames[reg].r_name : "<***>", v);
#endif

	bus_write_1(esc->sc_res, reg * 4, v);
}

static int
esp_dma_isintr(struct ncr53c9x_softc *sc)
{
	struct esp_softc *esc = (struct esp_softc *)sc;

	return (DMA_ISINTR(esc->sc_dma));
}

static void
esp_dma_reset(struct ncr53c9x_softc *sc)
{
	struct esp_softc *esc = (struct esp_softc *)sc;

	DMA_RESET(esc->sc_dma);
}

static int
esp_dma_intr(struct ncr53c9x_softc *sc)
{
	struct esp_softc *esc = (struct esp_softc *)sc;

	return (DMA_INTR(esc->sc_dma));
}

static int
esp_dma_setup(struct ncr53c9x_softc *sc, void **addr, size_t *len,
    int datain, size_t *dmasize)
{
	struct esp_softc *esc = (struct esp_softc *)sc;

	return (DMA_SETUP(esc->sc_dma, addr, len, datain, dmasize));
}

static void
esp_dma_go(struct ncr53c9x_softc *sc)
{
	struct esp_softc *esc = (struct esp_softc *)sc;

	DMA_GO(esc->sc_dma);
}

static void
esp_dma_stop(struct ncr53c9x_softc *sc)
{
	struct esp_softc *esc = (struct esp_softc *)sc;

	L64854_SCSR(esc->sc_dma, L64854_GCSR(esc->sc_dma) & ~D_EN_DMA);
}

static int
esp_dma_isactive(struct ncr53c9x_softc *sc)
{
	struct esp_softc *esc = (struct esp_softc *)sc;

	return (DMA_ISACTIVE(esc->sc_dma));
}