Import of WGRISC port. (Willowglen R3081 board)

1 files changed, 2096 insertions, 0 deletions

diff --git a/sys/arch/wgrisc/dev/asc.c b/sys/arch/wgrisc/dev/asc.c
new file mode 100644
index 00000000000..13785ab9c0f
--- /dev/null
+++ b/sys/arch/wgrisc/dev/asc.c
@@ -0,0 +1,2096 @@
+/*	$OpenBSD: asc.c,v 1.1 1997/02/06 16:02:42 pefo Exp $	*/
+/*	$NetBSD: asc.c,v 1.10 1994/12/05 19:11:12 dean Exp $	*/
+
+/*-
+ * Copyright (c) 1992, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Ralph Campbell and Rick Macklem.
+ *
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ *
+ *	@(#)asc.c	8.3 (Berkeley) 7/3/94
+ */
+
+/* 
+ * Mach Operating System
+ * Copyright (c) 1991,1990,1989 Carnegie Mellon University
+ * All Rights Reserved.
+ * 
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ * 
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS 
+ * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
+ * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ * 
+ * Carnegie Mellon requests users of this software to return to
+ * 
+ *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
+ *  School of Computer Science
+ *  Carnegie Mellon University
+ *  Pittsburgh PA 15213-3890
+ * 
+ * any improvements or extensions that they make and grant Carnegie the
+ * rights to redistribute these changes.
+ */
+
+/*
+ * HISTORY
+ * Log:	scsi_53C94_hdw.c,v
+ * Revision 2.5  91/02/05  17:45:07  mrt
+ * 	Added author notices
+ * 	[91/02/04  11:18:43  mrt]
+ * 
+ * 	Changed to use new Mach copyright
+ * 	[91/02/02  12:17:20  mrt]
+ * 
+ * Revision 2.4  91/01/08  15:48:24  rpd
+ * 	Added continuation argument to thread_block.
+ * 	[90/12/27            rpd]
+ * 
+ * Revision 2.3  90/12/05  23:34:48  af
+ * 	Recovered from pmax merge.. and from the destruction of a disk.
+ * 	[90/12/03  23:40:40  af]
+ * 
+ * Revision 2.1.1.1  90/11/01  03:39:09  af
+ * 	Created, from the DEC specs:
+ * 	"PMAZ-AA TURBOchannel SCSI Module Functional Specification"
+ * 	Workstation Systems Engineering, Palo Alto, CA. Aug 27, 1990.
+ * 	And from the NCR data sheets
+ * 	"NCR 53C94, 53C95, 53C96 Advances SCSI Controller"
+ * 	[90/09/03            af]
+ */
+
+/*
+ *	File: scsi_53C94_hdw.h
+ * 	Author: Alessandro Forin, Carnegie Mellon University
+ *	Date:	9/90
+ *
+ *	Bottom layer of the SCSI driver: chip-dependent functions
+ *
+ *	This file contains the code that is specific to the NCR 53C94
+ *	SCSI chip (Host Bus Adapter in SCSI parlance): probing, start
+ *	operation, and interrupt routine.
+ */
+
+/*
+ * This layer works based on small simple 'scripts' that are installed
+ * at the start of the command and drive the chip to completion.
+ * The idea comes from the specs of the NCR 53C700 'script' processor.
+ *
+ * There are various reasons for this, mainly
+ * - Performance: identify the common (successful) path, and follow it;
+ *   at interrupt time no code is needed to find the current status
+ * - Code size: it should be easy to compact common operations
+ * - Adaptability: the code skeleton should adapt to different chips without
+ *   terrible complications.
+ * - Error handling: and it is easy to modify the actions performed
+ *   by the scripts to cope with strange but well identified sequences
+ *
+ */
+
+#include <asc.h>
+#if NASC > 0
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/dkstat.h>
+#include <sys/buf.h>
+#include <sys/proc.h>
+#include <sys/conf.h>
+#include <sys/errno.h>
+#include <sys/device.h>
+
+#include <vm/vm.h>
+#include <vm/vm_kern.h>
+#include <vm/vm_page.h>
+
+#include <scsi/scsi_all.h>
+#include <scsi/scsiconf.h>
+
+#include <machine/cpu.h>
+#include <machine/autoconf.h>
+#include <machine/pio.h>
+
+#include <wgrisc/dev/scsi.h>
+#include <wgrisc/dev/ascreg.h>
+#include <wgrisc/dev/dma.h>
+
+#include <wgrisc/riscbus/riscbus.h>
+#include <wgrisc/wgrisc/wgrisctype.h>
+
+#define	readback(a)	{ register int foo; foo = (a); }
+extern int cputype;
+
+/*
+ * In 4ns ticks.
+ */
+int	asc_to_scsi_period[] = {
+	32,
+	33,
+	34,
+	35,
+	5,
+	5,
+	6,
+	7,
+	8,
+	9,
+	10,
+	11,
+	12,
+	13,
+	14,
+	15,
+	16,
+	17,
+	18,
+	19,
+	20,
+	21,
+	22,
+	23,
+	24,
+	25,
+	26,
+	27,
+	28,
+	29,
+	30,
+	31,
+};
+
+/*
+ * Internal forward declarations.
+ */
+static void asc_reset();
+static void asc_startcmd();
+
+#ifdef DEBUG
+int	asc_debug = 1;
+int	asc_debug_cmd;
+int	asc_debug_bn;
+int	asc_debug_sz;
+#define NLOG 16
+struct asc_log {
+	u_int	status;
+	u_char	state;
+	u_char	msg;
+	int	target;
+	int	resid;
+} asc_log[NLOG], *asc_logp = asc_log;
+#define PACK(unit, status, ss, ir) \
+	((unit << 24) | (status << 16) | (ss << 8) | ir)
+#endif
+
+/*
+ * Scripts are entries in a state machine table.
+ * A script has four parts: a pre-condition, an action, a command to the chip,
+ * and an index into asc_scripts for the next state. The first triggers error
+ * handling if not satisfied and in our case it is formed by the
+ * values of the interrupt register and status register, this
+ * basically captures the phase of the bus and the TC and BS
+ * bits.  The action part is just a function pointer, and the
+ * command is what the 53C94 should be told to do at the end
+ * of the action processing.  This command is only issued and the
+ * script proceeds if the action routine returns TRUE.
+ * See asc_intr() for how and where this is all done.
+ */
+typedef struct script {
+	int		condition;	/* expected state at interrupt time */
+	int		(*action)();	/* extra operations */
+	int		command;	/* command to the chip */
+	struct script	*next;		/* index into asc_scripts for next state */
+} script_t;
+
+/* Matching on the condition value */
+#define	SCRIPT_MATCH(ir, csr)		((ir) | (((csr) & 0x67) << 8))
+
+/* forward decls of script actions */
+static int script_nop();		/* when nothing needed */
+static int asc_end();			/* all come to an end */
+static int asc_get_status();		/* get status from target */
+static int asc_dma_in();		/* start reading data from target */
+static int asc_last_dma_in();		/* cleanup after all data is read */
+static int asc_resume_in();		/* resume data in after a message */
+static int asc_resume_dma_in();		/* resume DMA after a disconnect */
+static int asc_dma_out();		/* send data to target via dma */
+static int asc_last_dma_out();		/* cleanup after all data is written */
+static int asc_resume_out();		/* resume data out after a message */
+static int asc_resume_dma_out();	/* resume DMA after a disconnect */
+static int asc_sendsync();		/* negotiate sync xfer */
+static int asc_replysync();		/* negotiate sync xfer */
+static int asc_msg_in();		/* process a message byte */
+static int asc_disconnect();		/* process an expected disconnect */
+
+/* Define the index into asc_scripts for various state transitions */
+#define	SCRIPT_DATA_IN		0
+#define	SCRIPT_CONTINUE_IN	2
+#define	SCRIPT_DATA_OUT		3
+#define	SCRIPT_CONTINUE_OUT	5
+#define	SCRIPT_SIMPLE		6
+#define	SCRIPT_GET_STATUS	7
+#define	SCRIPT_DONE		8
+#define	SCRIPT_MSG_IN		9
+#define	SCRIPT_REPLY_SYNC	11
+#define	SCRIPT_TRY_SYNC		12
+#define	SCRIPT_DISCONNECT	15
+#define	SCRIPT_RESEL		16
+#define	SCRIPT_RESUME_IN	17
+#define	SCRIPT_RESUME_DMA_IN	18
+#define	SCRIPT_RESUME_OUT	19
+#define	SCRIPT_RESUME_DMA_OUT	20
+#define	SCRIPT_RESUME_NO_DATA	21
+
+/*
+ * Scripts
+ */
+script_t asc_scripts[] = {
+	/* start data in */
+	{SCRIPT_MATCH(ASC_INT_FC | ASC_INT_BS, ASC_PHASE_DATAI),	/*  0 */
+		asc_dma_in, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_DATA_IN + 1]},
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_STATUS),			/*  1 */
+		asc_last_dma_in, ASC_CMD_I_COMPLETE,
+		&asc_scripts[SCRIPT_GET_STATUS]},
+
+	/* continue data in after a chunk is finished */
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_DATAI),			/*  2 */
+		asc_dma_in, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_DATA_IN + 1]},
+
+	/* start data out */
+	{SCRIPT_MATCH(ASC_INT_FC | ASC_INT_BS, ASC_PHASE_DATAO),	/*  3 */
+		asc_dma_out, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_DATA_OUT + 1]},
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_STATUS),			/*  4 */
+		asc_last_dma_out, ASC_CMD_I_COMPLETE,
+		&asc_scripts[SCRIPT_GET_STATUS]},
+
+	/* continue data out after a chunk is finished */
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_DATAO),			/*  5 */
+		asc_dma_out, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_DATA_OUT + 1]},
+
+	/* simple command with no data transfer */
+	{SCRIPT_MATCH(ASC_INT_FC | ASC_INT_BS, ASC_PHASE_STATUS),	/*  6 */
+		script_nop, ASC_CMD_I_COMPLETE,
+		&asc_scripts[SCRIPT_GET_STATUS]},
+
+	/* get status and finish command */
+	{SCRIPT_MATCH(ASC_INT_FC, ASC_PHASE_MSG_IN),			/*  7 */
+		asc_get_status, ASC_CMD_MSG_ACPT,
+		&asc_scripts[SCRIPT_DONE]},
+	{SCRIPT_MATCH(ASC_INT_DISC, 0),					/*  8 */
+		asc_end, ASC_CMD_NOP,
+		&asc_scripts[SCRIPT_DONE]},
+
+	/* message in */
+	{SCRIPT_MATCH(ASC_INT_FC, ASC_PHASE_MSG_IN),			/*  9 */
+		asc_msg_in, ASC_CMD_MSG_ACPT,
+		&asc_scripts[SCRIPT_MSG_IN + 1]},
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_MSG_IN),			/* 10 */
+		script_nop, ASC_CMD_XFER_INFO,
+		&asc_scripts[SCRIPT_MSG_IN]},
+
+	/* send synchonous negotiation reply */
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_MSG_OUT),			/* 11 */
+		asc_replysync, ASC_CMD_XFER_INFO,
+		&asc_scripts[SCRIPT_REPLY_SYNC]},
+
+	/* try to negotiate synchonous transfer parameters */
+	{SCRIPT_MATCH(ASC_INT_FC | ASC_INT_BS, ASC_PHASE_MSG_OUT),	/* 12 */
+		asc_sendsync, ASC_CMD_XFER_INFO,
+		&asc_scripts[SCRIPT_TRY_SYNC + 1]},
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_MSG_IN),			/* 13 */
+		script_nop, ASC_CMD_XFER_INFO,
+		&asc_scripts[SCRIPT_MSG_IN]},
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_COMMAND),			/* 14 */
+		script_nop, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_RESUME_NO_DATA]},
+
+	/* handle a disconnect */
+	{SCRIPT_MATCH(ASC_INT_DISC, ASC_PHASE_DATAO),			/* 15 */
+		asc_disconnect, ASC_CMD_ENABLE_SEL,
+		&asc_scripts[SCRIPT_RESEL]},
+
+	/* reselect sequence: this is just a placeholder so match fails */
+	{SCRIPT_MATCH(0, ASC_PHASE_MSG_IN),				/* 16 */
+		script_nop, ASC_CMD_MSG_ACPT,
+		&asc_scripts[SCRIPT_RESEL]},
+
+	/* resume data in after a message */
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_DATAI),			/* 17 */
+		asc_resume_in, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_DATA_IN + 1]},
+
+	/* resume partial DMA data in after a message */
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_DATAI),			/* 18 */
+		asc_resume_dma_in, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_DATA_IN + 1]},
+
+	/* resume data out after a message */
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_DATAO),			/* 19 */
+		asc_resume_out, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_DATA_OUT + 1]},
+
+	/* resume partial DMA data out after a message */
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_DATAO),			/* 20 */
+		asc_resume_dma_out, ASC_CMD_XFER_INFO | ASC_CMD_DMA,
+		&asc_scripts[SCRIPT_DATA_OUT + 1]},
+
+	/* resume after a message when there is no more data */
+	{SCRIPT_MATCH(ASC_INT_BS, ASC_PHASE_STATUS),			/* 21 */
+		script_nop, ASC_CMD_I_COMPLETE,
+		&asc_scripts[SCRIPT_GET_STATUS]},
+};
+
+/*
+ * State kept for each active SCSI device.
+ */
+typedef struct scsi_state {
+	script_t *script;	/* saved script while processing error */
+	struct scsi_generic cmd;/* storage for scsi command */
+	int	statusByte;	/* status byte returned during STATUS_PHASE */
+	u_int	dmaBufSize;	/* DMA buffer size */
+	int	dmalen;		/* amount to transfer in this chunk */
+	int	dmaresid;	/* amount not transfered if chunk suspended */
+	int	cmdlen;		/* length of command in cmd */
+	int	buflen;		/* total remaining amount of data to transfer */
+	vm_offset_t buf;	/* current pointer within scsicmd->buf */
+	int	flags;		/* see below */
+	int	msglen;		/* number of message bytes to read */
+	int	msgcnt;		/* number of message bytes received */
+	u_char	sync_period;	/* DMA synchronous period */
+	u_char	sync_offset;	/* DMA synchronous xfer offset or 0 if async */
+	u_char	msg_out;	/* next MSG_OUT byte to send */
+	u_char	msg_in[16];	/* buffer for multibyte messages */
+} State;
+
+/* state flags */
+#define DISCONN		0x001	/* true if currently disconnected from bus */
+#define DMA_IN_PROGRESS	0x002	/* true if data DMA started */
+#define DMA_IN		0x004	/* true if reading from SCSI device */
+#define DMA_OUT		0x010	/* true if writing to SCSI device */
+#define DID_SYNC	0x020	/* true if synchronous offset was negotiated */
+#define TRY_SYNC	0x040	/* true if try neg. synchronous offset */
+#define PARITY_ERR	0x080	/* true if parity error seen */
+#define	CHECK_SENSE	0x100	/* true if doing sense command */
+
+struct dma_softc_t;
+/*
+ * State kept for each active SCSI host interface (53C94).
+ */
+struct asc_softc {
+	struct device	sc_dev;		/* use as a device */
+	asc_regmap_t	*regs;		/* chip address */
+	dma_softc_t	dma;		/* dma control structure */
+	int		sc_id;		/* SCSI ID of this interface */
+	int		myidmask;	/* ~(1 << myid) */
+	int		state;		/* current SCSI connection state */
+	int		target;		/* target SCSI ID if busy */
+	script_t	*script;	/* next expected interrupt & action */
+	struct scsi_xfer *cmdq[ASC_NCMD];/* Pointer to queued commands */
+	struct scsi_xfer *cmd[ASC_NCMD];/* Pointer to current active command */
+	State		st[ASC_NCMD];	/* state info for each active command */
+	int		min_period;	/* Min transfer period clk/byte */
+	int		max_period;	/* Max transfer period clk/byte */
+	int		ccf;		/* CCF, whatever that really is? */
+	int		timeout_250;	/* 250ms timeout */
+	int		tb_ticks;	/* 4ns. ticks/tb channel ticks */
+	struct scsi_link sc_link;	/* scsi link struct */
+};
+
+#define	ASC_STATE_IDLE		0	/* idle state */
+#define	ASC_STATE_BUSY		1	/* selecting or currently connected */
+#define ASC_STATE_TARGET	2	/* currently selected as target */
+#define ASC_STATE_RESEL		3	/* currently waiting for reselect */
+
+typedef struct asc_softc *asc_softc_t;
+
+static char dma_buffer[MAXPHYS];	/*yieek*/ /*XXX*/
+
+/*
+ * Autoconfiguration data for config.
+ */
+int	ascmatch __P((struct device *, void *, void *));
+void	ascattach __P((struct device *, struct device *, void *));
+int	ascprint(void *, const char *);
+
+struct cfattach asc_ca = {
+	sizeof(struct asc_softc), ascmatch, ascattach
+};
+struct cfdriver asc_cd = {
+	NULL, "asc", DV_DULL, NULL, 0
+};
+
+/*
+ *  Glue to the machine dependent scsi
+ */
+int asc_scsi_cmd __P((struct scsi_xfer *));
+void asc_minphys __P((struct buf *));
+
+struct scsi_adapter asc_switch = {
+	asc_scsi_cmd,
+	asc_minphys,
+	NULL,
+	NULL,
+};
+
+struct scsi_device asc_dev = {
+/*XXX*/	NULL,		/* Use default error handler */
+/*XXX*/	NULL,		/* have a queue, served by this */
+/*XXX*/	NULL,		/* have no async handler */
+/*XXX*/	NULL,		/* Use default 'done' routine */
+};
+
+static void	asc_start();
+static int	asc_intr();
+
+/*
+ * Match driver based on name
+ */
+int
+ascmatch(parent, match, aux)
+	struct device *parent;
+	void *match;
+	void *aux;
+{
+	struct cfdata *cf = match;
+	struct confargs *ca = aux;
+
+	if(!BUS_MATCHNAME(ca, "asc"))
+		return(0);
+	return(1);
+}
+
+void
+ascattach(parent, self, aux)
+	struct device *parent;
+	struct device *self;
+	void *aux;
+{
+	register struct confargs *ca = aux;
+	register asc_softc_t asc = (void *)self;
+	register asc_regmap_t *regs;
+	int id, s, i;
+	int bufsiz;
+
+	/*
+	 * Initialize hw descriptor, cache some pointers
+	 */
+	asc->regs = (asc_regmap_t *)BUS_CVTADDR(ca);
+
+	/*
+	 * Set up machine dependencies.
+	 * 1) how to do dma
+	 * 2) timing based on chip clock frequency
+	 */
+	switch (cputype) {
+	case WGRISC9100:
+		bufsiz = MAXPHYS;	/* Scatter gather in software */
+		break;
+	default:
+		bufsiz = 64 * 1024;
+	};
+	/*
+	 * Now for timing. WGRISC has a 20Mhz
+	 */
+	switch (cputype) {
+	case WGRISC9100:
+		asc->min_period = ASC_MIN_PERIOD20;
+		asc->max_period = ASC_MAX_PERIOD20;
+		asc->ccf = ASC_CCF(20);
+		asc->timeout_250 = ASC_TIMEOUT_250(20, asc->ccf);
+		asc->tb_ticks = 10;
+		asc->dma.dma_ch = DMA_CH0;
+		break;
+	default:
+		asc->min_period = ASC_MIN_PERIOD12;
+		asc->max_period = ASC_MAX_PERIOD12;
+		asc->ccf = ASC_CCF(13);
+		asc->timeout_250 = ASC_TIMEOUT_250(13, asc->ccf);
+		asc->tb_ticks = 20;
+		break;
+	};
+
+	asc->state = ASC_STATE_IDLE;
+	asc->target = -1;
+
+	regs = asc->regs;
+
+	/*
+	 * Reset chip, fully.  Note that interrupts are already enabled.
+	 */
+	s = splbio();
+
+	/* preserve our ID for now */
+#if 0
+	asc->sc_id = regs->asc_cnfg1 & ASC_CNFG1_MY_BUS_ID;
+#else
+	asc->sc_id = 7;	/* XXX Until boot roms set up scsi id */
+#endif
+	asc->myidmask = ~(1 << asc->sc_id);
+
+	asc_reset(asc, regs);
+
+	/*
+	 * Our SCSI id on the bus.
+	 * The user can set this via the prom on 3maxen/picaen.
+	 * If this changes it is easy to fix: make a default that
+	 * can be changed as boot arg.
+	 */
+#ifdef	unneeded
+	regs->asc_cnfg1 = (regs->asc_cnfg1 & ~ASC_CNFG1_MY_BUS_ID) |
+			      (scsi_initiator_id[unit] & 0x7);
+	asc->sc_id = regs->asc_cnfg1 & ASC_CNFG1_MY_BUS_ID;
+#endif
+	id = asc->sc_id;
+	splx(s);
+
+	/*
+	 * Give each target its DMA buffer region.
+	 * The buffer address is the same for all targets,
+	 * the allocated dma viritual scatter/gather space.
+	 */
+	for (i = 0; i < ASC_NCMD; i++) {
+		asc->st[i].dmaBufSize = bufsiz;
+	}
+
+	/*
+	 * Set up interrupt handler.
+         */
+	BUS_INTR_ESTABLISH(ca, asc_intr, (void *)asc);
+
+	printf(": NCR53C94, target %d\n", id);
+
+	/*
+	 * Fill in the prototype scsi link.
+	 */
+	asc->sc_link.adapter_softc = asc;
+	asc->sc_link.adapter_target = asc->sc_id;
+	asc->sc_link.adapter = &asc_switch;
+	asc->sc_link.device = &asc_dev;
+	asc->sc_link.openings = 2;
+
+	/*
+	 * Now try to attach all the sub devices.
+	 */
+	config_found(self, &asc->sc_link, ascprint);
+}
+
+int
+ascprint(aux, name)
+	void *aux;
+	const char *name;
+{
+}
+
+/*
+ *  Driver breaks down request transfer size.
+ */
+void
+asc_minphys(bp)
+	struct buf *bp;
+{
+	minphys(bp);
+}
+
+/*
+ * Start activity on a SCSI device.
+ * We maintain information on each device separately since devices can
+ * connect/disconnect during an operation.
+ */
+int
+asc_scsi_cmd(xs)
+	struct scsi_xfer *xs;
+{
+	struct scsi_link *sc_link = xs->sc_link;
+	struct asc_softc *asc = sc_link->adapter_softc;
+	State *state = &asc->st[sc_link->target];
+
+	int flags, s;
+
+	flags = xs->flags;
+
+	/*
+	 *  Flush caches for any data buffer
+	 */
+	if(xs->datalen != 0) {
+#ifdef R4K
+		R4K_HitFlushDCache(xs->data, xs->datalen);
+#else
+		R3K_FlushDCache();
+#endif
+	}
+	/*
+	 *  The hack on the next few lines are to avoid buffers
+	 *  mapped to UADDR. Realloc to the kva uarea address.
+	 */
+	if((u_int)(xs->data) >= UADDR) {
+		xs->data = ((u_int)(xs->data) & ~UADDR) + (u_char *)(curproc->p_addr);
+	}
+
+	/*
+	 * Check if another command is already in progress.
+	 * We may have to change this if we allow SCSI devices with
+	 * separate LUNs.
+	 */
+	s = splbio();
+	if (asc->cmd[sc_link->target]) {
+		if (asc->cmdq[sc_link->target]) {
+			splx(s);
+			printf("asc_scsi_cmd: called when target busy");
+			xs->error = XS_DRIVER_STUFFUP;
+			return TRY_AGAIN_LATER;
+		}
+		asc->cmdq[sc_link->target] = xs;
+		splx(s);
+		return SUCCESSFULLY_QUEUED;
+	}
+	asc->cmd[sc_link->target] = xs;
+
+	/*
+	 *  Going to launch.
+	 *  Make a local copy of the command and some pointers.
+	 */
+	asc_startcmd(asc, sc_link->target);
+
+	/*
+	 *  If in startup, interrupts not usable yet.
+	 */
+	if(flags & SCSI_POLL) {
+		return(asc_poll(asc,sc_link->target));
+	}
+	splx(s);
+	return SUCCESSFULLY_QUEUED;
+}
+
+int
+asc_poll(asc, target)
+	struct asc_softc *asc;
+	int target;
+{
+	struct scsi_xfer *scsicmd = asc->cmd[target];
+	int count = scsicmd->timeout * 10;
+
+	while(count) {
+		if(asc->regs->asc_status &ASC_CSR_INT) {
+			asc_intr(asc);
+		}
+		if(scsicmd->flags & ITSDONE)
+			break;
+		DELAY(5);
+		count--;
+	}
+	if(count == 0) {
+		scsicmd->error = XS_TIMEOUT;
+		asc_end(asc, 0, 0, 0);
+	}
+	return COMPLETE;
+}
+
+static void
+asc_reset(asc, regs)
+	asc_softc_t asc;
+	asc_regmap_t *regs;
+{
+	int i;
+
+	/*
+	 * Reset chip and SCSI bus. Put everything in a known state.
+	 */
+	regs->asc_cmd = ASC_CMD_RESET;
+	wbflush(); DELAY(25);
+	regs->asc_cmd = ASC_CMD_NOP;
+	wbflush(); DELAY(25);
+	regs->asc_cmd = ASC_CMD_BUS_RESET;
+	wbflush();
+	while(!(regs->asc_status & ASC_CSR_INT)) {
+		/*void*/
+	}
+	regs->asc_cmd = ASC_CMD_RESET;
+	wbflush(); DELAY(25);
+	regs->asc_cmd = ASC_CMD_NOP;
+	wbflush(); DELAY(25);
+
+	/*
+	 * Set up various chip parameters
+	 */
+	regs->asc_ccf = asc->ccf;
+	wbflush(); DELAY(25);
+	regs->asc_sel_timo = asc->timeout_250;
+	/* restore our ID */
+	regs->asc_cnfg1 = asc->sc_id | ASC_CNFG1_P_CHECK;
+	/* include ASC_CNFG2_SCSI2 if you want to allow SCSI II commands */
+	regs->asc_cnfg2 = /* ASC_CNFG2_RFB | ASC_CNFG2_SCSI2 | */ ASC_CNFG2_EPL;
+	regs->asc_cnfg3 = 0;
+	/* zero anything else */
+	ASC_TC_PUT(regs, 0);
+	regs->asc_syn_p = asc->min_period;
+	regs->asc_syn_o = 0;	/* async for now */
+	wbflush();
+}
+
+/*
+ * Start a SCSI command on a target.
+ */
+static void
+asc_startcmd(asc, target)
+	asc_softc_t asc;
+	int target;
+{
+	asc_regmap_t *regs;
+	State *state;
+	struct scsi_xfer *scsicmd;
+	int i, len;
+
+	/*
+	 * See if another target is currently selected on this SCSI bus.
+	 */
+	if (asc->target >= 0)
+		return;
+
+	regs = asc->regs;
+
+	/*
+	 * If a reselection is in progress, it is Ok to ignore it since
+	 * the ASC will automatically cancel the command and flush
+	 * the FIFO if the ASC is reselected before the command starts.
+	 * If we try to use ASC_CMD_DISABLE_SEL, we can hang the system if
+	 * a reselect occurs before starting the command.
+	 */
+
+	asc->state = ASC_STATE_BUSY;
+	asc->target = target;
+
+	/* cache some pointers */
+	scsicmd = asc->cmd[target];
+	state = &asc->st[target];
+
+	/*
+	 * Init the chip and target state.
+	 */
+	state->flags = state->flags & (DID_SYNC | CHECK_SENSE);
+	state->script = (script_t *)0;
+	state->msg_out = SCSI_NO_OP;
+
+	/*
+	 * Set up for DMA of command output. Also need to flush cache.
+	 */
+	if(!(state->flags & CHECK_SENSE)) {
+		bcopy(scsicmd->cmd, &state->cmd, scsicmd->cmdlen);
+		state->cmdlen = scsicmd->cmdlen;
+		state->buf = (vm_offset_t)scsicmd->data;
+		state->buflen = scsicmd->datalen;
+	}
+	len = state->cmdlen;
+	state->dmalen = len;
+	
+#ifdef DEBUG
+	if (asc_debug > 1) {
+		printf("asc_startcmd: %s target %d cmd %x len %d\n",
+			asc->sc_dev.dv_xname, target,
+			state->cmd.opcode, state->buflen);
+	}
+#endif
+
+	/* check for simple SCSI command with no data transfer */
+	if(state->flags & CHECK_SENSE) {
+		asc->script = &asc_scripts[SCRIPT_DATA_IN];
+		state->flags |= DMA_IN;
+	}
+	else if (scsicmd->flags & SCSI_DATA_OUT) {
+		asc->script = &asc_scripts[SCRIPT_DATA_OUT];
+		state->flags |= DMA_OUT;
+	}
+	else if (scsicmd->flags & SCSI_DATA_IN) {
+		asc->script = &asc_scripts[SCRIPT_DATA_IN];
+		state->flags |= DMA_IN;
+	}
+	else if (state->buflen == 0) {
+		/* check for sync negotiation */
+		if ((scsicmd->flags & /* SCSICMD_USE_SYNC */ 0) &&
+		    !(state->flags & DID_SYNC)) {
+			asc->script = &asc_scripts[SCRIPT_TRY_SYNC];
+			state->flags |= TRY_SYNC;
+		} else
+			asc->script = &asc_scripts[SCRIPT_SIMPLE];
+		state->buf = (vm_offset_t)0;
+	}
+
+#ifdef DEBUG
+	asc_debug_cmd = state->cmd.opcode;
+	if (state->cmd.opcode == SCSI_READ_EXT) {
+		asc_debug_bn = (state->cmd.bytes[1] << 24) |
+			(state->cmd.bytes[2] << 16) |
+			(state->cmd.bytes[3] << 8) |
+			 state->cmd.bytes[4];
+		asc_debug_sz = (state->cmd.bytes[6] << 8) | state->cmd.bytes[7];
+	}
+	asc_logp->status = PACK(asc->sc_dev.dv_unit, 0, 0, asc_debug_cmd);
+	asc_logp->target = asc->target;
+	asc_logp->state = asc->script - asc_scripts;
+	asc_logp->msg = SCSI_DIS_REC_IDENTIFY;
+	asc_logp->resid = scsicmd->datalen;
+	if (++asc_logp >= &asc_log[NLOG])
+		asc_logp = asc_log;
+#endif
+
+	/* preload the FIFO with the message and command to be sent */
+	regs->asc_fifo = SCSI_DIS_REC_IDENTIFY | (scsicmd->sc_link->lun & 0x07);
+
+	for( i = 0; i < len; i++ ) {
+		regs->asc_fifo = ((caddr_t)&state->cmd)[i];
+	}
+	ASC_TC_PUT(regs, 0);
+	readback(regs->asc_cmd);
+	regs->asc_cmd = ASC_CMD_DMA;
+	readback(regs->asc_cmd);
+
+	regs->asc_dbus_id = target;
+	readback(regs->asc_dbus_id);
+	regs->asc_syn_p = state->sync_period;
+	readback(regs->asc_syn_p);
+	regs->asc_syn_o = state->sync_offset;
+	readback(regs->asc_syn_o);
+
+/*XXX PEFO */
+/* we are not using sync transfer now, need to check this if we will */
+
+	if (state->flags & TRY_SYNC)
+		regs->asc_cmd = ASC_CMD_SEL_ATN_STOP;
+	else
+		regs->asc_cmd = ASC_CMD_SEL_ATN;
+	readback(regs->asc_cmd);
+}
+
+/*
+ * Interrupt routine
+ *	Take interrupts from the chip
+ *
+ * Implementation:
+ *	Move along the current command's script if
+ *	all is well, invoke error handler if not.
+ */
+int
+asc_intr(sc)
+	void *sc;
+{
+	asc_softc_t asc = sc;
+	asc_regmap_t *regs = asc->regs;
+	State *state;
+	script_t *scpt;
+	int ss, ir, status;
+
+	/* collect ephemeral information */
+	status = regs->asc_status;
+	ss = regs->asc_ss;
+
+	if ((status & ASC_CSR_INT) == 0) /* Make sure it's a real interrupt */
+		 return;
+
+	ir = regs->asc_intr;	/* this resets the previous two */
+	scpt = asc->script;
+
+#ifdef DEBUG
+	asc_logp->status = PACK(asc->sc_dev.dv_unit, status, ss, ir);
+	asc_logp->target = (asc->state == ASC_STATE_BUSY) ? asc->target : -1;
+	asc_logp->state = scpt - asc_scripts;
+	asc_logp->msg = -1;
+	asc_logp->resid = 0;
+	if (++asc_logp >= &asc_log[NLOG])
+		asc_logp = asc_log;
+	if (asc_debug > 2)
+		printf("asc_intr: status %x ss %x ir %x cond %d:%x\n",
+			status, ss, ir, scpt - asc_scripts, scpt->condition);
+#endif
+
+	/* check the expected state */
+	if (SCRIPT_MATCH(ir, status) == scpt->condition) {
+		/*
+		 * Perform the appropriate operation, then proceed.
+		 */
+		if ((*scpt->action)(asc, status, ss, ir)) {
+			regs->asc_cmd = scpt->command;
+			readback(regs->asc_cmd);
+			asc->script = scpt->next;
+		}
+		goto done;
+	}
+
+	/*
+	 * Check for parity error.
+	 * Hardware will automatically set ATN
+	 * to request the device for a MSG_OUT phase.
+	 */
+	if (status & ASC_CSR_PE) {
+		printf("%s: SCSI device %d: incomming parity error seen\n",
+			asc->sc_dev.dv_xname, asc->target);
+		asc->st[asc->target].flags |= PARITY_ERR;
+	}
+
+	/*
+	 * Check for gross error.
+	 * Probably a bug in a device driver.
+	 */
+	if (status & ASC_CSR_GE) {
+		printf("%s: SCSI device %d: gross error\n",
+			asc->sc_dev.dv_xname, asc->target);
+		goto abort;
+	}
+
+	/* check for message in or out */
+	if ((ir & ~ASC_INT_FC) == ASC_INT_BS) {
+		register int len, fifo;
+
+		state = &asc->st[asc->target];
+		switch (ASC_PHASE(status)) {
+		case ASC_PHASE_DATAI:
+		case ASC_PHASE_DATAO:
+			ASC_TC_GET(regs, len);
+			fifo = regs->asc_flags & ASC_FLAGS_FIFO_CNT;
+			printf("asc_intr: data overrun: buflen %d dmalen %d tc %d fifo %d\n",
+				state->buflen, state->dmalen, len, fifo);
+			goto abort;
+
+		case ASC_PHASE_MSG_IN:
+			break;
+
+		case ASC_PHASE_MSG_OUT:
+			/*
+			 * Check for parity error.
+			 * Hardware will automatically set ATN
+			 * to request the device for a MSG_OUT phase.
+			 */
+			if (state->flags & PARITY_ERR) {
+				state->flags &= ~PARITY_ERR;
+				state->msg_out = SCSI_MESSAGE_PARITY_ERROR;
+				/* reset message in counter */
+				state->msglen = 0;
+			} else
+				state->msg_out = SCSI_NO_OP;
+			regs->asc_fifo = state->msg_out;
+			regs->asc_cmd = ASC_CMD_XFER_INFO;
+			readback(regs->asc_cmd);
+			goto done;
+
+		case ASC_PHASE_STATUS:
+			/* probably an error in the SCSI command */
+			asc->script = &asc_scripts[SCRIPT_GET_STATUS];
+			regs->asc_cmd = ASC_CMD_I_COMPLETE;
+			readback(regs->asc_cmd);
+			goto done;
+
+		default:
+			goto abort;
+		}
+
+		if (state->script)
+			goto abort;
+
+		/*
+		 * OK, message coming in clean up whatever is going on.
+		 * Get number of bytes left to transfered from byte counter
+		 * counter decrements when data is trf on the SCSI bus
+		 */
+		ASC_TC_GET(regs, len);
+		fifo = regs->asc_flags & ASC_FLAGS_FIFO_CNT;
+		/* flush any data in the FIFO */
+		if (fifo && !(state->flags & DMA_IN_PROGRESS)) {
+printf("asc_intr: fifo flush %d len %d fifo %x\n", fifo, len, regs->asc_fifo);
+			regs->asc_cmd = ASC_CMD_FLUSH;
+			readback(regs->asc_cmd);
+			DELAY(2);
+		}
+		else if (fifo && state->flags & DMA_IN_PROGRESS) {	
+			if (state->flags & DMA_OUT) {
+				len += fifo; /* Bytes dma'ed but not sent */
+			}
+			else if (state->flags & DMA_IN) {
+				u_char *cp;
+
+				printf("asc_intr: IN: dmalen %d len %d fifo %d\n",
+					state->dmalen, len, fifo); /* XXX */
+			}
+			regs->asc_cmd = ASC_CMD_FLUSH;
+			readback(regs->asc_cmd);
+			DELAY(2);
+		}
+		if (len && (state->flags & DMA_IN_PROGRESS)) {
+			/* save number of bytes still to be sent or received */
+			state->dmaresid = len;
+			state->flags &= ~DMA_IN_PROGRESS;
+			ASC_TC_PUT(regs, 0);
+#ifdef DEBUG
+			if (asc_logp == asc_log)
+				asc_log[NLOG - 1].resid = len;
+			else
+				asc_logp[-1].resid = len;
+#endif
+			/* setup state to resume to */
+			if (state->flags & DMA_IN) {
+				/*
+				 * Since the ASC_CNFG3_SRB bit of the
+				 * cnfg3 register bit is not set,
+				 * we just transferred an extra byte.
+				 * Since we can't resume on an odd byte
+				 * boundary, we copy the valid data out
+				 * and resume DMA at the start address.
+				 */
+				if (len & 1) {
+					printf("asc_intr: msg in len %d (fifo %d)\n",
+						len, fifo); /* XXX */
+					len = state->dmalen - len;
+					goto do_in;
+				}
+				state->script =
+					&asc_scripts[SCRIPT_RESUME_DMA_IN];
+			} else if (state->flags & DMA_OUT)
+				state->script =
+					&asc_scripts[SCRIPT_RESUME_DMA_OUT];
+			else
+				state->script = asc->script;
+		} else if (state->flags & DMA_IN) {
+			if (len) {
+#ifdef DEBUG
+				printf("asc_intr: 1: bn %d len %d (fifo %d)\n",
+					asc_debug_bn, len, fifo); /* XXX */
+#endif
+				goto abort;
+			}
+			/* setup state to resume to */
+			if (state->flags & DMA_IN_PROGRESS) {
+				len = state->dmalen;
+				state->flags &= ~DMA_IN_PROGRESS;
+			do_in:
+				DMA_END(&asc->dma);
+				state->buf += len;
+				state->buflen -= len;
+			}
+			if (state->buflen)
+				state->script =
+				    &asc_scripts[SCRIPT_RESUME_IN];
+			else
+				state->script =
+				    &asc_scripts[SCRIPT_RESUME_NO_DATA];
+		} else if (state->flags & DMA_OUT) {
+			if (len) {
+				printf("asc_intr: 2: len %d (fifo %d)\n", len,
+					fifo); /* XXX */
+/* XXX THEO */
+#if 1 
+				regs->asc_cmd = ASC_CMD_FLUSH;
+				readback(regs->asc_cmd);
+				DELAY(2);
+				len = 0;
+#else                                   
+				goto abort;
+#endif
+			}
+			/*
+			 * If this is the last chunk, the next expected
+			 * state is to get status.
+			 */
+			if (state->flags & DMA_IN_PROGRESS) {
+				state->flags &= ~DMA_IN_PROGRESS;
+				DMA_END(&asc->dma);
+				len = state->dmalen;
+				state->buf += len;
+				state->buflen -= len;
+			}
+			if (state->buflen)
+				state->script =
+				    &asc_scripts[SCRIPT_RESUME_OUT];
+			else
+				state->script =
+				    &asc_scripts[SCRIPT_RESUME_NO_DATA];
+		} else if (asc->script == &asc_scripts[SCRIPT_SIMPLE])
+			state->script = &asc_scripts[SCRIPT_RESUME_NO_DATA];
+		else
+			state->script = asc->script;
+
+		/* setup to receive a message */
+		asc->script = &asc_scripts[SCRIPT_MSG_IN];
+		state->msglen = 0;
+		regs->asc_cmd = ASC_CMD_XFER_INFO;
+		readback(regs->asc_cmd);
+		goto done;
+	}
+
+	/* check for SCSI bus reset */
+	if (ir & ASC_INT_RESET) {
+		register int i;
+
+		printf("%s: SCSI bus reset!!\n", asc->sc_dev.dv_xname);
+		/* need to flush any pending commands */
+		for (i = 0; i < ASC_NCMD; i++) {
+			if (!asc->cmd[i])
+				continue;
+			asc->cmd[i]->error = XS_DRIVER_STUFFUP;
+			asc_end(asc, 0, 0, 0);
+		}
+		/* rearbitrate synchronous offset */
+		for (i = 0; i < ASC_NCMD; i++) {
+			asc->st[i].sync_offset = 0;
+			asc->st[i].flags = 0;
+		}
+		asc->target = -1;
+		return;
+	}
+
+	/* check for command errors */
+	if (ir & ASC_INT_ILL)
+		goto abort;
+
+	/* check for disconnect */
+	if (ir & ASC_INT_DISC) {
+		state = &asc->st[asc->target];
+		switch (asc->script - asc_scripts) {
+		case SCRIPT_DONE:
+		case SCRIPT_DISCONNECT:
+			/*
+			 * Disconnects can happen normally when the
+			 * command is complete with the phase being
+			 * either ASC_PHASE_DATAO or ASC_PHASE_MSG_IN.
+			 * The SCRIPT_MATCH() only checks for one phase
+			 * so we can wind up here.
+			 * Perform the appropriate operation, then proceed.
+			 */
+			if ((*scpt->action)(asc, status, ss, ir)) {
+				regs->asc_cmd = scpt->command;
+				readback(regs->asc_cmd);
+				asc->script = scpt->next;
+			}
+			goto done;
+
+		case SCRIPT_TRY_SYNC:
+		case SCRIPT_SIMPLE:
+		case SCRIPT_DATA_IN:
+		case SCRIPT_DATA_OUT: /* one of the starting scripts */
+			if (ASC_SS(ss) == 0) {
+				/* device did not respond */
+				if (regs->asc_flags & ASC_FLAGS_FIFO_CNT) {
+					regs->asc_cmd = ASC_CMD_FLUSH;
+					readback(regs->asc_cmd);
+				}
+				asc->cmd[asc->target]->error = XS_DRIVER_STUFFUP;
+				asc_end(asc, status, ss, ir);
+				return;
+			}
+			/* FALLTHROUGH */
+
+		default:
+			printf("%s: SCSI device %d: unexpected disconnect\n",
+				asc->sc_dev.dv_xname, asc->target);
+#ifdef DEBUG
+			asc_DumpLog("asc_disc");
+#endif
+			/*
+			 * On rare occasions my RZ24 does a disconnect during
+			 * data in phase and the following seems to keep it
+			 * happy.
+			 * XXX Should a scsi disk ever do this??
+			 */
+			asc->script = &asc_scripts[SCRIPT_RESEL];
+			asc->state = ASC_STATE_RESEL;
+			state->flags |= DISCONN;
+			regs->asc_cmd = ASC_CMD_ENABLE_SEL;
+			readback(regs->asc_cmd);
+			return;
+		}
+	}
+
+	/* check for reselect */
+	if (ir & ASC_INT_RESEL) {
+		unsigned fifo, id, msg;
+
+		fifo = regs->asc_flags & ASC_FLAGS_FIFO_CNT;
+		if (fifo < 2)
+			goto abort;
+		/* read unencoded SCSI ID and convert to binary */
+		msg = regs->asc_fifo & asc->myidmask;
+		for (id = 0; (msg & 1) == 0; id++)
+			msg >>= 1;
+		/* read identify message */
+		msg = regs->asc_fifo;
+#ifdef DEBUG
+		if (asc_logp == asc_log)
+			asc_log[NLOG - 1].msg = msg;
+		else
+			asc_logp[-1].msg = msg;
+#endif
+		asc->state = ASC_STATE_BUSY;
+		asc->target = id;
+		state = &asc->st[id];
+		asc->script = state->script;
+		state->script = (script_t *)0;
+		if (!(state->flags & DISCONN))
+			goto abort;
+		state->flags &= ~DISCONN;
+		regs->asc_syn_p = state->sync_period;
+		regs->asc_syn_o = state->sync_offset;
+		regs->asc_cmd = ASC_CMD_MSG_ACPT;
+		readback(regs->asc_cmd);
+		goto done;
+	}
+
+	/* check if we are being selected as a target */
+	if (ir & (ASC_INT_SEL | ASC_INT_SEL_ATN))
+		goto abort;
+
+	/*
+	 * 'ir' must be just ASC_INT_FC.
+	 * This is normal if canceling an ASC_ENABLE_SEL.
+	 */
+
+done:
+	wbflush();
+	/*
+	 * If the next interrupt comes in immediatly the interrupt
+	 * dispatcher (which we are returning to) will catch it
+	 * before returning to the interrupted code.
+	 */
+	return;
+
+abort:
+#ifdef DEBUG
+	asc_DumpLog("asc_intr");
+#endif
+#if 0
+	panic("asc_intr");
+#else
+	boot(4); /* XXX */
+#endif
+}
+
+/*
+ * All the many little things that the interrupt
+ * routine might switch to.
+ */
+
+/* ARGSUSED */
+static int
+script_nop(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_get_status(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register int data;
+
+	/*
+	 * Get the last two bytes in the FIFO.
+	 */
+	if ((data = regs->asc_flags & ASC_FLAGS_FIFO_CNT) != 2) {
+		printf("asc_get_status: cmdreg %x, fifo cnt %d\n",
+		       regs->asc_cmd, data); /* XXX */
+#ifdef DEBUG
+		asc_DumpLog("get_status"); /* XXX */
+#endif
+		if (data < 2) {
+			asc->regs->asc_cmd = ASC_CMD_MSG_ACPT;
+			readback(asc->regs->asc_cmd);
+			return (0);
+		}
+		do {
+			data = regs->asc_fifo;
+		} while ((regs->asc_flags & ASC_FLAGS_FIFO_CNT) > 2);
+	}
+
+	/* save the status byte */
+	asc->st[asc->target].statusByte = data = regs->asc_fifo;
+#ifdef DEBUG
+	if (asc_logp == asc_log)
+		asc_log[NLOG - 1].msg = data;
+	else
+		asc_logp[-1].msg = data;
+#endif
+
+	/* get the (presumed) command_complete message */
+	if ((data = regs->asc_fifo) == SCSI_COMMAND_COMPLETE)
+		return (1);
+
+#ifdef DEBUG
+	printf("asc_get_status: status %x cmd %x\n",
+		asc->st[asc->target].statusByte, data);
+	asc_DumpLog("asc_get_status");
+#endif
+	return (0);
+}
+
+/* ARGSUSED */
+static int
+asc_end(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	struct scsi_xfer *scsicmd;
+	struct scsi_link *sc_link;
+	State *state;
+	int i, target;
+
+	asc->state = ASC_STATE_IDLE;
+	target = asc->target;
+	asc->target = -1;
+	scsicmd = asc->cmd[target];
+	sc_link = scsicmd->sc_link;
+	asc->cmd[target] = (struct scsi_xfer *)0;
+	state = &asc->st[target];
+
+#ifdef DEBUG
+	if (asc_debug > 1) {
+		printf("asc_end: %s target %d cmd %x err %d resid %d\n",
+			asc->sc_dev.dv_xname, target,
+			state->cmd.opcode, scsicmd->error, state->buflen);
+	}
+#endif
+#ifdef DIAGNOSTIC
+	if (target < 0 || !scsicmd)
+		panic("asc_end");
+#endif
+
+	/* look for disconnected devices */
+	for (i = 0; i < ASC_NCMD; i++) {
+		if (!asc->cmd[i] || !(asc->st[i].flags & DISCONN))
+			continue;
+		asc->regs->asc_cmd = ASC_CMD_ENABLE_SEL;
+		readback(asc->regs->asc_cmd);
+		asc->state = ASC_STATE_RESEL;
+		asc->script = &asc_scripts[SCRIPT_RESEL];
+		break;
+	}
+
+	if(scsicmd->error == XS_NOERROR && !(state->flags & CHECK_SENSE)) {
+		if((state->statusByte & ST_MASK) == SCSI_CHECK) {
+			struct scsi_sense *ss = (void *)&state->cmd;
+			/* Save return values */
+			scsicmd->resid = state->buflen;
+			scsicmd->status = state->statusByte;
+			/* Set up sense request command */
+			bzero(ss, sizeof(*ss));
+			ss->opcode = REQUEST_SENSE;
+			ss->byte2 = sc_link->lun << 5;
+			ss->length = sizeof(struct scsi_sense_data);
+			state->cmdlen = sizeof(*ss);
+			state->buf = (vm_offset_t)&scsicmd->sense;
+			state->buflen = sizeof(struct scsi_sense_data);
+			state->flags |= CHECK_SENSE;
+#ifdef R4K
+			R4K_HitFlushDCache(state->buf, state->buflen);
+#else
+			R3K_FlushDCache();
+#endif
+			asc->cmd[target] = scsicmd;
+			asc_startcmd(asc, target);
+			return(0);
+		}
+	}
+
+	if(scsicmd->error == XS_NOERROR && (state->flags & CHECK_SENSE)) {
+		scsicmd->error = XS_SENSE;
+	}
+	else {
+		scsicmd->resid = state->buflen;
+	}
+	state->flags &= ~CHECK_SENSE;
+
+	/*
+	 * Look for another device that is ready.
+	 * May want to keep last one started and increment for fairness
+	 * rather than always starting at zero.
+	 */
+	for (i = 0; i < ASC_NCMD; i++) {
+		if (asc->cmd[i] == 0 && asc->cmdq[i] != 0) {
+			asc->cmd[i] = asc->cmdq[i];
+			asc->cmdq[i] = 0;
+		}
+	}
+	for (i = 0; i < ASC_NCMD; i++) {
+		/* don't restart a disconnected command */
+		if (!asc->cmd[i] || (asc->st[i].flags & DISCONN))
+			continue;
+		asc_startcmd(asc, i);
+		break;
+	}
+
+	/* signal device driver that the command is done */
+	scsicmd->flags |= ITSDONE;
+	scsi_done(scsicmd);
+
+	return (0);
+}
+
+/* ARGSUSED */
+static int
+asc_dma_in(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int len;
+
+	/* check for previous chunk in buffer */
+	if (state->flags & DMA_IN_PROGRESS) {
+		/*
+		 * Only count bytes that have been copied to memory.
+		 * There may be some bytes in the FIFO if synchonous transfers
+		 * are in progress.
+		 */
+		DMA_END(&asc->dma);
+		ASC_TC_GET(regs, len);
+		len = state->dmalen - len;
+		state->buf += len;
+		state->buflen -= len;
+	}
+
+	/* setup to start reading the next chunk */
+	len = state->buflen;
+#ifdef DEBUG
+	if (asc_logp == asc_log)
+		asc_log[NLOG - 1].resid = len;
+	else
+		asc_logp[-1].resid = len;
+#endif
+	if (len > state->dmaBufSize)
+		len = state->dmaBufSize;
+	state->dmalen = len;
+	DMA_START(&asc->dma, (caddr_t)state->buf, len, DMA_FROM_DEV);
+	ASC_TC_PUT(regs, len);
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_dma_in: buflen %d, len %d\n", state->buflen, len);
+#endif
+
+	/* check for next chunk */
+	state->flags |= DMA_IN_PROGRESS;
+	if (len != state->buflen) {
+		regs->asc_cmd = ASC_CMD_XFER_INFO | ASC_CMD_DMA;
+		readback(regs->asc_cmd);
+		asc->script = &asc_scripts[SCRIPT_CONTINUE_IN];
+		return (0);
+	}
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_last_dma_in(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int len, fifo;
+
+	DMA_END(&asc->dma);
+	ASC_TC_GET(regs, len);
+	fifo = regs->asc_flags & ASC_FLAGS_FIFO_CNT;
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_last_dma_in: buflen %d dmalen %d tc %d fifo %d\n",
+			state->buflen, state->dmalen, len, fifo);
+#endif
+	if (fifo) {
+		/* device must be trying to send more than we expect */
+		regs->asc_cmd = ASC_CMD_FLUSH;
+		readback(regs->asc_cmd);
+	}
+	state->flags &= ~DMA_IN_PROGRESS;
+	len = state->dmalen - len;
+	state->buflen -= len;
+
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_resume_in(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int len;
+
+	/* setup to start reading the next chunk */
+	len = state->buflen;
+#ifdef DEBUG
+	if (asc_logp == asc_log)
+		asc_log[NLOG - 1].resid = len;
+	else
+		asc_logp[-1].resid = len;
+#endif
+	if (len > state->dmaBufSize)
+		len = state->dmaBufSize;
+	state->dmalen = len;
+#ifdef DEBUG
+	if (asc_logp == asc_log)
+		asc_log[NLOG - 1].resid = len;
+	else
+		asc_logp[-1].resid = len;
+#endif
+	DMA_START(&asc->dma, (caddr_t)state->buf, len, DMA_FROM_DEV);
+	ASC_TC_PUT(regs, len);
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_resume_in: buflen %d, len %d\n", state->buflen,
+			len);
+#endif
+
+	/* check for next chunk */
+	state->flags |= DMA_IN_PROGRESS;
+	if (len != state->buflen) {
+		regs->asc_cmd = ASC_CMD_XFER_INFO | ASC_CMD_DMA;
+		readback(regs->asc_cmd);
+		asc->script = &asc_scripts[SCRIPT_CONTINUE_IN];
+		return (0);
+	}
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_resume_dma_in(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int len, off;
+
+	/* setup to finish reading the current chunk */
+	len = state->dmaresid;
+	off = state->dmalen - len;
+	if ((off & 1) && state->sync_offset) {
+		printf("asc_resume_dma_in: odd xfer dmalen %d len %d off %d\n",
+			state->dmalen, len, off); /* XXX */
+		regs->asc_res_fifo = ((u_char *)state->buf)[off];
+/*XXX Need to flush cache ? */
+	}
+	DMA_START(&asc->dma, (caddr_t)state->buf + off, len, DMA_FROM_DEV);
+	ASC_TC_PUT(regs, len);
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_resume_dma_in: buflen %d dmalen %d len %d off %d\n",
+			state->dmalen, state->buflen, len, off);
+#endif
+
+	/* check for next chunk */
+	state->flags |= DMA_IN_PROGRESS;
+	if (state->dmalen != state->buflen) {
+		regs->asc_cmd = ASC_CMD_XFER_INFO | ASC_CMD_DMA;
+		readback(regs->asc_cmd);
+		asc->script = &asc_scripts[SCRIPT_CONTINUE_IN];
+		return (0);
+	}
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_dma_out(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int len, fifo;
+
+	if (state->flags & DMA_IN_PROGRESS) {
+		/* check to be sure previous chunk was finished */
+		ASC_TC_GET(regs, len);
+		fifo = regs->asc_flags & ASC_FLAGS_FIFO_CNT;
+		if (len || fifo)
+			printf("asc_dma_out: buflen %d dmalen %d tc %d fifo %d\n",
+				state->buflen, state->dmalen, len, fifo); /* XXX */
+		len += fifo;
+		len = state->dmalen - len;
+		state->buf += len;
+		state->buflen -= len;
+	}
+
+	/* setup for this chunk */
+	len = state->buflen;
+#ifdef DEBUG
+	if (asc_logp == asc_log)
+		asc_log[NLOG - 1].resid = len;
+	else
+		asc_logp[-1].resid = len;
+#endif
+	if (len > state->dmaBufSize)
+		len = state->dmaBufSize;
+	state->dmalen = len;
+	DMA_START(&asc->dma, (caddr_t)state->buf, len, DMA_TO_DEV);
+	ASC_TC_PUT(regs, len);
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_dma_out: buflen %d, len %d\n", state->buflen, len);
+#endif
+
+	/* check for next chunk */
+	state->flags |= DMA_IN_PROGRESS;
+	if (len != state->buflen) {
+		regs->asc_cmd = ASC_CMD_XFER_INFO | ASC_CMD_DMA;
+		readback(regs->asc_cmd);
+		asc->script = &asc_scripts[SCRIPT_CONTINUE_OUT];
+		return (0);
+	}
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_last_dma_out(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int len, fifo;
+
+	ASC_TC_GET(regs, len);
+	fifo = regs->asc_flags & ASC_FLAGS_FIFO_CNT;
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_last_dma_out: buflen %d dmalen %d tc %d fifo %d\n",
+			state->buflen, state->dmalen, len, fifo);
+#endif
+	if (fifo) {
+		len += fifo;
+		regs->asc_cmd = ASC_CMD_FLUSH;
+		readback(regs->asc_cmd);
+	}
+	state->flags &= ~DMA_IN_PROGRESS;
+	len = state->dmalen - len;
+	state->buflen -= len;
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_resume_out(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int len;
+
+	/* setup for this chunk */
+	len = state->buflen;
+#ifdef DEBUG
+	if (asc_logp == asc_log)
+		asc_log[NLOG - 1].resid = len;
+	else
+		asc_logp[-1].resid = len;
+#endif
+	if (len > state->dmaBufSize)
+		len = state->dmaBufSize;
+	state->dmalen = len;
+#ifdef DEBUG
+ 	if (asc_logp == asc_log)
+		asc_log[NLOG - 1].resid = len;
+	else
+		asc_logp[-1].resid = len;
+#endif
+	DMA_START(&asc->dma, (caddr_t)state->buf, len, DMA_TO_DEV);
+	ASC_TC_PUT(regs, len);
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_resume_out: buflen %d, len %d\n", state->buflen,
+			len);
+#endif
+
+	/* check for next chunk */
+	state->flags |= DMA_IN_PROGRESS;
+	if (len != state->buflen) {
+		regs->asc_cmd = ASC_CMD_XFER_INFO | ASC_CMD_DMA;
+		readback(regs->asc_cmd);
+		asc->script = &asc_scripts[SCRIPT_CONTINUE_OUT];
+		return (0);
+	}
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_resume_dma_out(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int len, off;
+
+	/* setup to finish writing this chunk */
+	len = state->dmaresid;
+	off = state->dmalen - len;
+	if (off & 1) {
+		printf("asc_resume_dma_out: odd xfer dmalen %d len %d off %d\n",
+			state->dmalen, len, off); /* XXX */
+		regs->asc_fifo = ((u_char *)state->buf)[off];
+/*XXX Need to flush Cache ? */
+		off++;
+		len--;
+	}
+	DMA_START(&asc->dma, (caddr_t)state->buf + off, len, DMA_TO_DEV);
+	ASC_TC_PUT(regs, len);
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_resume_dma_out: buflen %d dmalen %d len %d off %d\n",
+			state->dmalen, state->buflen, len, off);
+#endif
+
+	/* check for next chunk */
+	state->flags |= DMA_IN_PROGRESS;
+	if (state->dmalen != state->buflen) {
+		regs->asc_cmd = ASC_CMD_XFER_INFO | ASC_CMD_DMA;
+		readback(regs->asc_cmd);
+		asc->script = &asc_scripts[SCRIPT_CONTINUE_OUT];
+		return (0);
+	}
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_sendsync(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+
+	/* send the extended synchronous negotiation message */
+	regs->asc_fifo = SCSI_EXTENDED_MSG;
+	wbflush();
+	regs->asc_fifo = 3;
+	wbflush();
+	regs->asc_fifo = SCSI_SYNCHRONOUS_XFER;
+	wbflush();
+	regs->asc_fifo = SCSI_MIN_PERIOD;
+	wbflush();
+	regs->asc_fifo = ASC_MAX_OFFSET;
+	/* state to resume after we see the sync reply message */
+	state->script = asc->script + 2;
+	state->msglen = 0;
+	return (1);
+}
+
+/* ARGSUSED */
+static int
+asc_replysync(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_replysync: %x %x\n",
+			asc_to_scsi_period[state->sync_period] * asc->tb_ticks,
+			state->sync_offset);
+#endif
+	/* send synchronous transfer in response to a request */
+	regs->asc_fifo = SCSI_EXTENDED_MSG;
+	wbflush();
+	regs->asc_fifo = 3;
+	wbflush();
+	regs->asc_fifo = SCSI_SYNCHRONOUS_XFER;
+	wbflush();
+	regs->asc_fifo = asc_to_scsi_period[state->sync_period] * asc->tb_ticks;
+	wbflush();
+	regs->asc_fifo = state->sync_offset;
+	regs->asc_cmd = ASC_CMD_XFER_INFO;
+	readback(regs->asc_cmd);
+
+	/* return to the appropriate script */
+	if (!state->script) {
+#ifdef DEBUG
+		asc_DumpLog("asc_replsync");
+#endif
+		panic("asc_replysync");
+	}
+	asc->script = state->script;
+	state->script = (script_t *)0;
+	return (0);
+}
+
+/* ARGSUSED */
+static int
+asc_msg_in(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register asc_regmap_t *regs = asc->regs;
+	register State *state = &asc->st[asc->target];
+	register int msg;
+	int i;
+
+	/* read one message byte */
+	msg = regs->asc_fifo;
+#ifdef DEBUG
+	if (asc_logp == asc_log)
+		asc_log[NLOG - 1].msg = msg;
+	else
+		asc_logp[-1].msg = msg;
+#endif
+
+	/* check for multi-byte message */
+	if (state->msglen != 0) {
+		/* first byte is the message length */
+		if (state->msglen < 0) {
+			state->msglen = msg;
+			return (1);
+		}
+		if (state->msgcnt >= state->msglen)
+			goto abort;
+		state->msg_in[state->msgcnt++] = msg;
+
+		/* did we just read the last byte of the message? */
+		if (state->msgcnt != state->msglen)
+			return (1);
+
+		/* process an extended message */
+#ifdef DEBUG
+		if (asc_debug > 2)
+			printf("asc_msg_in: msg %x %x %x\n",
+				state->msg_in[0],
+				state->msg_in[1],
+				state->msg_in[2]);
+#endif
+		switch (state->msg_in[0]) {
+		case SCSI_SYNCHRONOUS_XFER:
+			state->flags |= DID_SYNC;
+			state->sync_offset = state->msg_in[2];
+
+			/* convert SCSI period to ASC period */
+			i = state->msg_in[1] / asc->tb_ticks;
+			if (i < asc->min_period)
+				i = asc->min_period;
+			else if (i >= asc->max_period) {
+				/* can't do sync transfer, period too long */
+				printf("%s: SCSI device %d: sync xfer period too long (%d)\n",
+					asc->sc_dev.dv_xname, asc->target, i);
+				i = asc->max_period;
+				state->sync_offset = 0;
+			}
+			if ((i * asc->tb_ticks) != state->msg_in[1])
+				i++;
+			state->sync_period = i & 0x1F;
+
+			/*
+			 * If this is a request, check minimums and
+			 * send back an acknowledge.
+			 */
+			if (!(state->flags & TRY_SYNC)) {
+				regs->asc_cmd = ASC_CMD_SET_ATN;
+				readback(regs->asc_cmd);
+
+				if (state->sync_period < asc->min_period)
+					state->sync_period =
+						asc->min_period;
+				if (state->sync_offset > ASC_MAX_OFFSET)
+					state->sync_offset =
+						ASC_MAX_OFFSET;
+				asc->script = &asc_scripts[SCRIPT_REPLY_SYNC];
+				regs->asc_syn_p = state->sync_period;
+				readback(regs->asc_syn_p);
+				regs->asc_syn_o = state->sync_offset;
+				readback(regs->asc_syn_o);
+				regs->asc_cmd = ASC_CMD_MSG_ACPT;
+				readback(regs->asc_cmd);
+				return (0);
+			}
+
+			regs->asc_syn_p = state->sync_period;
+			readback(regs->asc_syn_p);
+			regs->asc_syn_o = state->sync_offset;
+			readback(regs->asc_syn_o);
+			goto done;
+
+		default:
+			printf("%s: SCSI device %d: rejecting extended message 0x%x\n",
+				 asc->sc_dev.dv_xname, asc->target,
+				state->msg_in[0]);
+			goto reject;
+		}
+	}
+
+	/* process first byte of a message */
+#ifdef DEBUG
+	if (asc_debug > 2)
+		printf("asc_msg_in: msg %x\n", msg);
+#endif
+	switch (msg) {
+#if 0
+	case SCSI_MESSAGE_REJECT:
+		printf(" did not like SYNCH xfer "); /* XXX */
+		state->flags |= DID_SYNC;
+		regs->asc_cmd = ASC_CMD_MSG_ACPT;
+		readback(regs->asc_cmd);
+		status = asc_wait(regs, ASC_CSR_INT);
+		ir = regs->asc_intr;
+		/* some just break out here, some dont */
+		if (ASC_PHASE(status) == ASC_PHASE_MSG_OUT) {
+			regs->asc_fifo = SCSI_ABORT;
+			regs->asc_cmd = ASC_CMD_XFER_INFO;
+			readback(regs->asc_cmd);
+			status = asc_wait(regs, ASC_CSR_INT);
+			ir = regs->asc_intr;
+		}
+		if (ir & ASC_INT_DISC) {
+			asc_end(asc, status, 0, ir);
+			return (0);
+		}
+		goto status;
+#endif /* 0 */
+
+	case SCSI_EXTENDED_MSG: /* read an extended message */
+		/* setup to read message length next */
+		state->msglen = -1;
+		state->msgcnt = 0;
+		return (1);
+
+	case SCSI_NO_OP:
+		break;
+
+	case SCSI_SAVE_DATA_POINTER:
+		/* expect another message */
+		return (1);
+
+	case SCSI_RESTORE_POINTERS:
+		/*
+		 * Need to do the following if resuming synchonous data in
+		 * on an odd byte boundary.
+		regs->asc_cnfg2 |= ASC_CNFG2_RFB;
+		 */
+		break;
+
+	case SCSI_DISCONNECT:
+		if (state->flags & DISCONN)
+			goto abort;
+		state->flags |= DISCONN;
+		regs->asc_cmd = ASC_CMD_MSG_ACPT;
+		readback(regs->asc_cmd);
+		asc->script = &asc_scripts[SCRIPT_DISCONNECT];
+		return (0);
+
+	default:
+		printf("%s: SCSI device %d: rejecting message 0x%x\n",
+			asc->sc_dev.dv_xname, asc->target, msg);
+	reject:
+		/* request a message out before acknowledging this message */
+		state->msg_out = SCSI_MESSAGE_REJECT;
+		regs->asc_cmd = ASC_CMD_SET_ATN;
+		readback(regs->asc_cmd);
+	}
+
+done:
+	/* return to original script */
+	regs->asc_cmd = ASC_CMD_MSG_ACPT;
+	readback(regs->asc_cmd);
+	if (!state->script) {
+	abort:
+#ifdef DEBUG
+		asc_DumpLog("asc_msg_in");
+#endif
+		panic("asc_msg_in");
+	}
+	asc->script = state->script;
+	state->script = (script_t *)0;
+	return (0);
+}
+
+/* ARGSUSED */
+static int
+asc_disconnect(asc, status, ss, ir)
+	register asc_softc_t asc;
+	register int status, ss, ir;
+{
+	register State *state = &asc->st[asc->target];
+
+#ifdef DIAGNOSTIC
+	if (!(state->flags & DISCONN)) {
+		printf("asc_disconnect: device %d: DISCONN not set!\n",
+			asc->target);
+	}
+#endif /* DIAGNOSTIC */
+	asc->target = -1;
+	asc->state = ASC_STATE_RESEL;
+	return (1);
+}
+
+#ifdef DEBUG
+/*
+ * Dump the log buffer.
+ */
+asc_DumpLog(str)
+	char *str;
+{
+	register struct asc_log *lp;
+	register u_int status;
+
+	printf("asc: %s: cmd %x bn %d cnt %d\n", str, asc_debug_cmd,
+		asc_debug_bn, asc_debug_sz);
+	lp = asc_logp;
+	do {
+		status = lp->status;
+		printf("asc%d tgt %d status %x ss %x ir %x cond %d:%x msg %x resid %d\n",
+			status >> 24,
+			lp->target,
+			(status >> 16) & 0xFF,
+			(status >> 8) & 0xFF,
+			status & 0XFF,
+			lp->state,
+			asc_scripts[lp->state].condition,
+			lp->msg, lp->resid);
+		if (++lp >= &asc_log[NLOG])
+			lp = asc_log;
+	} while (lp != asc_logp);
+}
+#endif	/* DEBUG */
+
+#endif	/* NASC > 0 */