initial import of NetBSD tree

1 files changed, 1058 insertions, 0 deletions

diff --git a/sys/dev/isa/wt.c b/sys/dev/isa/wt.c
new file mode 100644
index 00000000000..e770b00661e
--- /dev/null
+++ b/sys/dev/isa/wt.c
@@ -0,0 +1,1058 @@
+/*	$NetBSD: wt.c,v 1.26 1995/07/04 07:23:58 mycroft Exp $	*/
+
+/*
+ * Streamer tape driver.
+ * Supports Archive and Wangtek compatible QIC-02/QIC-36 boards.
+ *
+ * Copyright (C) 1993 by:
+ *	Sergey Ryzhkov <sir@kiae.su>
+ *	Serge Vakulenko <vak@zebub.msk.su>
+ *
+ * This software is distributed with NO WARRANTIES, not even the implied
+ * warranties for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Authors grant any other persons or organisations permission to use
+ * or modify this software as long as this message is kept with the software,
+ * all derivative works or modified versions.
+ *
+ * This driver is derived from the old 386bsd Wangtek streamer tape driver,
+ * made by Robert Baron at CMU, based on Intel sources.
+ */
+
+/*
+ * Copyright (c) 1989 Carnegie-Mellon University.
+ * All rights reserved.
+ *
+ * Authors: Robert Baron
+ * 
+ * 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 "AS IS" 
+ * 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.
+ */
+
+/*
+ *  Copyright 1988, 1989 by Intel Corporation
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/buf.h>
+#include <sys/fcntl.h>
+#include <sys/malloc.h>
+#include <sys/ioctl.h>
+#include <sys/mtio.h>
+#include <sys/device.h>
+
+#include <vm/vm_param.h>
+
+#include <machine/pio.h>
+
+#include <dev/isa/isavar.h>
+#include <dev/isa/isadmavar.h>
+#include <dev/isa/wtreg.h>
+
+/*
+ * Uncomment this to enable internal device tracing.
+ */
+#define DEBUG(x)		/* printf x */
+
+#define WTPRI			(PZERO+10)	/* sleep priority */
+
+/*
+ * Wangtek controller ports
+ */
+#define WT_CTLPORT(base)	((base)+0)	/* control, write only */
+#define WT_STATPORT(base)	((base)+0)	/* status, read only */
+#define WT_CMDPORT(base)	((base)+1)	/* command, write only */
+#define WT_DATAPORT(base)	((base)+1)	/* data, read only */
+#define WT_NPORT		2		/* 2 i/o ports */
+
+/* status port bits */
+#define WT_BUSY			0x01		/* not ready bit define */
+#define WT_NOEXCEP		0x02		/* no exception bit define */
+#define WT_RESETMASK		0x07		/* to check after reset */
+#define WT_RESETVAL		0x05		/* state after reset */
+
+/* control port bits */
+#define WT_ONLINE		0x01		/* device selected */
+#define WT_RESET		0x02		/* reset command */
+#define WT_REQUEST		0x04		/* request command */
+#define WT_IEN			0x08		/* enable dma */
+
+/*
+ * Archive controller ports
+ */
+#define AV_DATAPORT(base)	((base)+0)	/* data, read only */
+#define AV_CMDPORT(base)	((base)+0)	/* command, write only */
+#define AV_STATPORT(base)	((base)+1)	/* status, read only */
+#define AV_CTLPORT(base)	((base)+1)	/* control, write only */
+#define AV_SDMAPORT(base)	((base)+2)	/* start dma */
+#define AV_RDMAPORT(base)	((base)+3)	/* reset dma */
+#define AV_NPORT		4		/* 4 i/o ports */
+
+/* status port bits */
+#define AV_BUSY			0x40		/* not ready bit define */
+#define AV_NOEXCEP		0x20		/* no exception bit define */
+#define AV_RESETMASK		0xf8		/* to check after reset */
+#define AV_RESETVAL		0x50		/* state after reset */
+
+/* control port bits */
+#define AV_RESET		0x80		/* reset command */
+#define AV_REQUEST		0x40		/* request command */
+#define AV_IEN			0x20		/* enable interrupts */
+
+enum wttype {
+	UNKNOWN = 0,	/* unknown type, driver disabled */
+	ARCHIVE,	/* Archive Viper SC499, SC402 etc */
+	WANGTEK,	/* Wangtek */
+};
+
+struct wt_softc {
+	struct device sc_dev;
+	void *sc_ih;
+
+	enum wttype type;	/* type of controller */
+	int sc_iobase;		/* base i/o port */
+	int chan;		/* dma channel number, 1..3 */
+	int flags;		/* state of tape drive */
+	unsigned dens;		/* tape density */
+	int bsize;		/* tape block size */
+	void *buf;		/* internal i/o buffer */
+
+	void *dmavaddr;		/* virtual address of dma i/o buffer */
+	size_t dmatotal;	/* size of i/o buffer */
+	int dmaflags;		/* i/o direction, B_READ or B_WRITE */
+	size_t dmacount;	/* resulting length of dma i/o */
+
+	u_short error;		/* code for error encountered */
+	u_short ercnt;		/* number of error blocks */
+	u_short urcnt;		/* number of underruns */
+
+	int DATAPORT, CMDPORT, STATPORT, CTLPORT, SDMAPORT, RDMAPORT;
+	u_char BUSY, NOEXCEP, RESETMASK, RESETVAL, ONLINE, RESET, REQUEST, IEN;
+};
+
+int wtwait __P((struct wt_softc *sc, int catch, char *msg));
+int wtcmd __P((struct wt_softc *sc, int cmd));
+int wtstart __P((struct wt_softc *sc, int flag, void *vaddr, size_t len));
+void wtdma __P((struct wt_softc *sc));
+void wttimer __P((void *arg));
+void wtclock __P((struct wt_softc *sc));
+int wtreset __P((struct wt_softc *sc));
+int wtsense __P((struct wt_softc *sc, int verbose, int ignore));
+int wtstatus __P((struct wt_softc *sc));
+void wtrewind __P((struct wt_softc *sc));
+int wtreadfm __P((struct wt_softc *sc));
+int wtwritefm __P((struct wt_softc *sc));
+u_char wtpoll __P((struct wt_softc *sc, int mask, int bits));
+
+int wtprobe __P((struct device *, void *, void *));
+void wtattach __P((struct device *, struct device *, void *));
+int wtintr __P((void *sc));
+
+struct cfdriver wtcd = {
+	NULL, "wt", wtprobe, wtattach, DV_TAPE, sizeof(struct wt_softc)
+};
+
+/*
+ * Probe for the presence of the device.
+ */
+int
+wtprobe(parent, match, aux)
+	struct device *parent;
+	void *match, *aux;
+{
+	struct wt_softc *sc = match;
+	struct isa_attach_args *ia = aux;
+	int iobase;
+
+	sc->chan = ia->ia_drq;
+	sc->sc_iobase = iobase = ia->ia_iobase;
+	if (sc->chan < 1 || sc->chan > 3) {
+		printf("%s: Bad drq=%d, should be 1..3\n", sc->sc_dev.dv_xname,
+		    sc->chan);
+		return 0;
+	}
+
+	/* Try Wangtek. */
+	sc->type = WANGTEK;
+	sc->CTLPORT = WT_CTLPORT(iobase);
+	sc->STATPORT = WT_STATPORT(iobase);
+	sc->CMDPORT = WT_CMDPORT(iobase);
+	sc->DATAPORT = WT_DATAPORT(iobase);
+	sc->SDMAPORT = sc->RDMAPORT = 0;
+	sc->BUSY = WT_BUSY;		sc->NOEXCEP = WT_NOEXCEP;
+	sc->RESETMASK = WT_RESETMASK;	sc->RESETVAL = WT_RESETVAL;
+	sc->ONLINE = WT_ONLINE;		sc->RESET = WT_RESET;
+	sc->REQUEST = WT_REQUEST;	sc->IEN = WT_IEN;
+	if (wtreset(sc)) {
+		ia->ia_iosize = WT_NPORT;
+		return 1;
+	}
+
+	/* Try Archive. */
+	sc->type = ARCHIVE;
+	sc->CTLPORT = AV_CTLPORT(iobase);
+	sc->STATPORT = AV_STATPORT(iobase);
+	sc->CMDPORT = AV_CMDPORT(iobase);
+	sc->DATAPORT = AV_DATAPORT(iobase);
+	sc->SDMAPORT = AV_SDMAPORT(iobase);
+	sc->RDMAPORT = AV_RDMAPORT(iobase);
+	sc->BUSY = AV_BUSY;		sc->NOEXCEP = AV_NOEXCEP;
+	sc->RESETMASK = AV_RESETMASK;	sc->RESETVAL = AV_RESETVAL;
+	sc->ONLINE = 0;			sc->RESET = AV_RESET;
+	sc->REQUEST = AV_REQUEST;	sc->IEN = AV_IEN;
+	if (wtreset(sc)) {
+		ia->ia_iosize = AV_NPORT;
+		return 1;
+	}
+
+	/* Tape controller not found. */
+	sc->type = UNKNOWN;
+	return 0;
+}
+
+/*
+ * Device is found, configure it.
+ */
+void
+wtattach(parent, self, aux)
+	struct device *parent, *self;
+	void *aux;
+{
+	struct wt_softc *sc = (void *)self;
+	struct isa_attach_args *ia = aux;
+
+	if (sc->type == ARCHIVE) {
+		printf(": type <Archive>\n");
+		/* Reset DMA. */
+		outb(sc->RDMAPORT, 0);
+	} else
+		printf(": type <Wangtek>\n");
+	sc->flags = TPSTART;		/* tape is rewound */
+	sc->dens = -1;			/* unknown density */
+
+	sc->sc_ih = isa_intr_establish(ia->ia_irq, ISA_IST_EDGE, ISA_IPL_BIO,
+	    wtintr, sc);
+}
+
+int
+wtdump(dev, blkno, va, size)
+	dev_t dev;
+	daddr_t blkno;
+	caddr_t va;
+	size_t size;
+{
+
+	/* Not implemented. */
+	return ENXIO;
+}
+
+int
+wtsize(dev)
+	dev_t dev;
+{
+
+	/* Not implemented. */
+	return -1;
+}
+
+/*
+ * Open routine, called on every device open.
+ */
+int
+wtopen(dev, flag)
+	dev_t dev;
+	int flag;
+{
+	int unit = minor(dev) & T_UNIT;
+	struct wt_softc *sc;
+	int error;
+
+	if (unit >= wtcd.cd_ndevs)
+		return ENXIO;
+	sc = wtcd.cd_devs[unit];
+	if (!sc)
+		return ENXIO;
+
+	/* Check that device is not in use */
+	if (sc->flags & TPINUSE)
+		return EBUSY;
+
+	/* If the tape is in rewound state, check the status and set density. */
+	if (sc->flags & TPSTART) {
+		/* If rewind is going on, wait */
+		if (error = wtwait(sc, PCATCH, "wtrew"))
+			return error;
+
+		/* Check the controller status */
+		if (!wtsense(sc, 0, (flag & FWRITE) ? 0 : TP_WRP)) {
+			/* Bad status, reset the controller. */
+			if (!wtreset(sc))
+				return EIO;
+			if (!wtsense(sc, 1, (flag & FWRITE) ? 0 : TP_WRP))
+				return EIO;
+		}
+
+		/* Set up tape density. */
+		if (sc->dens != (minor(dev) & WT_DENSEL)) {
+			int d = 0;
+
+			switch (minor(dev) & WT_DENSEL) {
+			case WT_DENSDFLT:
+			default:
+				break;			/* default density */
+			case WT_QIC11:
+				d = QIC_FMT11;  break;	/* minor 010 */
+			case WT_QIC24:
+				d = QIC_FMT24;  break;	/* minor 020 */
+			case WT_QIC120:
+				d = QIC_FMT120; break;	/* minor 030 */
+			case WT_QIC150:
+				d = QIC_FMT150; break;	/* minor 040 */
+			case WT_QIC300:
+				d = QIC_FMT300; break;	/* minor 050 */
+			case WT_QIC600:
+				d = QIC_FMT600; break;	/* minor 060 */
+			}
+			if (d) {
+				/* Change tape density. */
+				if (!wtcmd(sc, d))
+					return EIO;
+				if (!wtsense(sc, 1, TP_WRP | TP_ILL))
+					return EIO;
+
+				/* Check the status of the controller. */
+				if (sc->error & TP_ILL) {
+					printf("%s: invalid tape density\n",
+					    sc->sc_dev.dv_xname);
+					return ENODEV;
+				}
+			}
+			sc->dens = minor(dev) & WT_DENSEL;
+		}
+		sc->flags &= ~TPSTART;
+	} else if (sc->dens != (minor(dev) & WT_DENSEL))
+		return ENXIO;
+
+	sc->bsize = (minor(dev) & WT_BSIZE) ? 1024 : 512;
+	sc->buf = malloc(sc->bsize, M_TEMP, M_WAITOK);
+
+	sc->flags = TPINUSE;
+	if (flag & FREAD)
+		sc->flags |= TPREAD;
+	if (flag & FWRITE)
+		sc->flags |= TPWRITE;
+	return 0;
+}
+
+/*
+ * Close routine, called on last device close.
+ */
+int
+wtclose(dev)
+	dev_t dev;
+{
+	int unit = minor(dev) & T_UNIT;
+	struct wt_softc *sc = wtcd.cd_devs[unit];
+
+	/* If rewind is pending, do nothing */
+	if (sc->flags & TPREW)
+		goto done;
+
+	/* If seek forward is pending and no rewind on close, do nothing */
+	if (sc->flags & TPRMARK) {
+		if (minor(dev) & T_NOREWIND)
+			goto done;
+
+		/* If read file mark is going on, wait */
+		wtwait(sc, 0, "wtrfm");
+	}
+
+	if (sc->flags & TPWANY) {
+		/* Tape was written.  Write file mark. */
+		wtwritefm(sc);
+	}
+
+	if ((minor(dev) & T_NOREWIND) == 0) {
+		/* Rewind to beginning of tape. */
+		/* Don't wait until rewind, though. */
+		wtrewind(sc);
+		goto done;
+	}
+	if ((sc->flags & TPRANY) && (sc->flags & (TPVOL | TPWANY)) == 0) {
+		/* Space forward to after next file mark if no writing done. */
+		/* Don't wait for completion. */
+		wtreadfm(sc);
+	}
+
+done:
+	sc->flags &= TPREW | TPRMARK | TPSTART | TPTIMER;
+	free(sc->buf, M_TEMP);
+	return 0;
+}
+
+/*
+ * Ioctl routine.  Compatible with BSD ioctls.
+ * Direct QIC-02 commands ERASE and RETENSION added.
+ * There are three possible ioctls:
+ * ioctl(int fd, MTIOCGET, struct mtget *buf)	-- get status
+ * ioctl(int fd, MTIOCTOP, struct mtop *buf)	-- do BSD-like op
+ * ioctl(int fd, WTQICMD, int qicop)		-- do QIC op
+ */
+int
+wtioctl(dev, cmd, addr, flag)
+	dev_t dev;
+	u_long cmd;
+	void *addr;
+	int flag;
+{
+	int unit = minor(dev) & T_UNIT;
+	struct wt_softc *sc = wtcd.cd_devs[unit];
+	int error, count, op;
+
+	switch (cmd) {
+	default:
+		return EINVAL;
+	case WTQICMD:	/* direct QIC command */
+		op = *(int *)addr;
+		switch (op) {
+		default:
+			return EINVAL;
+		case QIC_ERASE:		/* erase the whole tape */
+			if ((sc->flags & TPWRITE) == 0 || (sc->flags & TPWP))
+				return EACCES;
+			if (error = wtwait(sc, PCATCH, "wterase"))
+				return error;
+			break;
+		case QIC_RETENS:	/* retension the tape */
+			if (error = wtwait(sc, PCATCH, "wtretens"))
+				return error;
+			break;
+		}
+		/* Both ERASE and RETENS operations work like REWIND. */
+		/* Simulate the rewind operation here. */
+		sc->flags &= ~(TPRO | TPWO | TPVOL);
+		if (!wtcmd(sc, op))
+			return EIO;
+		sc->flags |= TPSTART | TPREW;
+		if (op == QIC_ERASE)
+			sc->flags |= TPWANY;
+		wtclock(sc);
+		return 0;
+	case MTIOCIEOT:	/* ignore EOT errors */
+	case MTIOCEEOT:	/* enable EOT errors */
+		return 0;
+	case MTIOCGET:
+		((struct mtget*)addr)->mt_type =
+			sc->type == ARCHIVE ? MT_ISVIPER1 : 0x11;
+		((struct mtget*)addr)->mt_dsreg = sc->flags;	/* status */
+		((struct mtget*)addr)->mt_erreg = sc->error;	/* errors */
+		((struct mtget*)addr)->mt_resid = 0;
+		((struct mtget*)addr)->mt_fileno = 0;		/* file */
+		((struct mtget*)addr)->mt_blkno = 0;		/* block */
+		return 0;
+	case MTIOCTOP:
+		break;
+	}
+
+	switch ((short)((struct mtop*)addr)->mt_op) {
+	default:
+#if 0
+	case MTFSR:	/* forward space record */
+	case MTBSR:	/* backward space record */
+	case MTBSF:	/* backward space file */
+#endif
+		return EINVAL;
+	case MTNOP:	/* no operation, sets status only */
+	case MTCACHE:	/* enable controller cache */
+	case MTNOCACHE:	/* disable controller cache */
+		return 0;
+	case MTREW:	/* rewind */
+	case MTOFFL:	/* rewind and put the drive offline */
+		if (sc->flags & TPREW)   /* rewind is running */
+			return 0;
+		if (error = wtwait(sc, PCATCH, "wtorew"))
+			return error;
+		wtrewind(sc);
+		return 0;
+	case MTFSF:	/* forward space file */
+		for (count = ((struct mtop*)addr)->mt_count; count > 0;
+		    --count) {
+			if (error = wtwait(sc, PCATCH, "wtorfm"))
+				return error;
+			if (error = wtreadfm(sc))
+				return error;
+		}
+		return 0;
+	case MTWEOF:	/* write an end-of-file record */
+		if ((sc->flags & TPWRITE) == 0 || (sc->flags & TPWP))
+			return EACCES;
+		if (error = wtwait(sc, PCATCH, "wtowfm"))
+			return error;
+		if (error = wtwritefm(sc))
+			return error;
+		return 0;
+	}
+
+#ifdef DIAGNOSTIC
+	panic("wtioctl: impossible");
+#endif
+}
+
+/*
+ * Strategy routine.
+ */
+void
+wtstrategy(bp)
+	struct buf *bp;
+{
+	int unit = minor(bp->b_dev) & T_UNIT;
+	struct wt_softc *sc = wtcd.cd_devs[unit];
+	int s;
+
+	bp->b_resid = bp->b_bcount;
+
+	/* at file marks and end of tape, we just return '0 bytes available' */
+	if (sc->flags & TPVOL)
+		goto xit;
+
+	if (bp->b_flags & B_READ) {
+		/* Check read access and no previous write to this tape. */
+		if ((sc->flags & TPREAD) == 0 || (sc->flags & TPWANY))
+			goto errxit;
+
+		/* For now, we assume that all data will be copied out */
+		/* If read command outstanding, just skip down */
+		if ((sc->flags & TPRO) == 0) {
+			if (!wtsense(sc, 1, TP_WRP)) {
+				/* Clear status. */
+				goto errxit;
+			}
+			if (!wtcmd(sc, QIC_RDDATA)) {
+				/* Set read mode. */
+				wtsense(sc, 1, TP_WRP);
+				goto errxit;
+			}
+			sc->flags |= TPRO | TPRANY;
+		}
+	} else {
+		/* Check write access and write protection. */
+		/* No previous read from this tape allowed. */
+		if ((sc->flags & TPWRITE) == 0 || (sc->flags & (TPWP | TPRANY)))
+			goto errxit;
+
+		/* If write command outstanding, just skip down */
+		if ((sc->flags & TPWO) == 0) {
+			if (!wtsense(sc, 1, 0)) {
+				/* Clear status. */
+				goto errxit;
+			}
+			if (!wtcmd(sc, QIC_WRTDATA)) {
+				/* Set write mode. */
+				wtsense(sc, 1, 0);
+				goto errxit;
+			}
+			sc->flags |= TPWO | TPWANY;
+		}
+	}
+
+	if (bp->b_bcount == 0)
+		goto xit;
+
+	sc->flags &= ~TPEXCEP;
+	s = splbio();
+	if (wtstart(sc, bp->b_flags, bp->b_data, bp->b_bcount)) {
+		wtwait(sc, 0, (bp->b_flags & B_READ) ? "wtread" : "wtwrite");
+		bp->b_resid -= sc->dmacount;
+	}
+	splx(s);
+
+	if (sc->flags & TPEXCEP) {
+errxit:
+		bp->b_flags |= B_ERROR;
+		bp->b_error = EIO;
+	}
+xit:
+	biodone(bp);
+	return;
+}
+
+int
+wtread(dev, uio)
+	dev_t dev;
+	struct uio *uio;
+{
+
+	return (physio(wtstrategy, NULL, dev, B_READ, minphys, uio));
+}
+
+int
+wtwrite(dev, uio)
+	dev_t dev;
+	struct uio *uio;
+{
+
+	return (physio(wtstrategy, NULL, dev, B_WRITE, minphys, uio));
+}
+
+/*
+ * Interrupt routine.
+ */
+int
+wtintr(arg)
+	void *arg;
+{
+	struct wt_softc *sc = arg;
+	u_char x;
+
+	x = inb(sc->STATPORT);			/* get status */
+	DEBUG(("wtintr() status=0x%x -- ", x));
+	if ((x & (sc->BUSY | sc->NOEXCEP)) == (sc->BUSY | sc->NOEXCEP)) {
+		DEBUG(("busy\n"));
+		return 0;			/* device is busy */
+	}
+
+	/*
+	 * Check if rewind finished.
+	 */
+	if (sc->flags & TPREW) {
+		DEBUG(((x & (sc->BUSY | sc->NOEXCEP)) == (sc->BUSY | sc->NOEXCEP) ?
+		    "rewind busy?\n" : "rewind finished\n"));
+		sc->flags &= ~TPREW;		/* rewind finished */
+		wtsense(sc, 1, TP_WRP);
+		wakeup((caddr_t)sc);
+		return 1;
+	}
+
+	/*
+	 * Check if writing/reading of file mark finished.
+	 */
+	if (sc->flags & (TPRMARK | TPWMARK)) {
+		DEBUG(((x & (sc->BUSY | sc->NOEXCEP)) == (sc->BUSY | sc->NOEXCEP) ?
+		    "marker r/w busy?\n" : "marker r/w finished\n"));
+		if ((x & sc->NOEXCEP) == 0)	/* operation failed */
+			wtsense(sc, 1, (sc->flags & TPRMARK) ? TP_WRP : 0);
+		sc->flags &= ~(TPRMARK | TPWMARK); /* operation finished */
+		wakeup((caddr_t)sc);
+		return 1;
+	}
+
+	/*
+	 * Do we started any i/o?  If no, just return.
+	 */
+	if ((sc->flags & TPACTIVE) == 0) {
+		DEBUG(("unexpected interrupt\n"));
+		return 0;
+	}
+	sc->flags &= ~TPACTIVE;
+	sc->dmacount += sc->bsize;		/* increment counter */
+
+	/*
+	 * Clean up dma.
+	 */
+	if ((sc->dmaflags & B_READ) &&
+	    (sc->dmatotal - sc->dmacount) < sc->bsize) {
+		/* If reading short block, copy the internal buffer
+		 * to the user memory. */
+		isa_dmadone(sc->dmaflags, sc->buf, sc->bsize, sc->chan);
+		bcopy(sc->buf, sc->dmavaddr, sc->dmatotal - sc->dmacount);
+	} else
+		isa_dmadone(sc->dmaflags, sc->dmavaddr, sc->bsize, sc->chan);
+
+	/*
+	 * On exception, check for end of file and end of volume.
+	 */
+	if ((x & sc->NOEXCEP) == 0) {
+		DEBUG(("i/o exception\n"));
+		wtsense(sc, 1, (sc->dmaflags & B_READ) ? TP_WRP : 0);
+		if (sc->error & (TP_EOM | TP_FIL))
+			sc->flags |= TPVOL;	/* end of file */
+		else
+			sc->flags |= TPEXCEP;	/* i/o error */
+		wakeup((caddr_t)sc);
+		return 1;
+	}
+
+	if (sc->dmacount < sc->dmatotal) {
+		/* Continue I/O. */
+		sc->dmavaddr += sc->bsize;
+		wtdma(sc);
+		DEBUG(("continue i/o, %d\n", sc->dmacount));
+		return 1;
+	}
+	if (sc->dmacount > sc->dmatotal)	/* short last block */
+		sc->dmacount = sc->dmatotal;
+	/* Wake up user level. */
+	wakeup((caddr_t)sc);
+	DEBUG(("i/o finished, %d\n", sc->dmacount));
+	return 1;
+}
+
+/* start the rewind operation */
+void
+wtrewind(sc)
+	struct wt_softc *sc;
+{
+	int rwmode = sc->flags & (TPRO | TPWO);
+
+	sc->flags &= ~(TPRO | TPWO | TPVOL);
+	/*
+	 * Wangtek strictly follows QIC-02 standard:
+	 * clearing ONLINE in read/write modes causes rewind.
+	 * REWIND command is not allowed in read/write mode
+	 * and gives `illegal command' error.
+	 */
+	if (sc->type == WANGTEK && rwmode) {
+		outb(sc->CTLPORT, 0);
+	} else if (!wtcmd(sc, QIC_REWIND))
+		return;
+	sc->flags |= TPSTART | TPREW;
+	wtclock(sc);
+}
+
+/*
+ * Start the `read marker' operation.
+ */
+int
+wtreadfm(sc)
+	struct wt_softc *sc;
+{
+
+	sc->flags &= ~(TPRO | TPWO | TPVOL);
+	if (!wtcmd(sc, QIC_READFM)) {
+		wtsense(sc, 1, TP_WRP);
+		return EIO;
+	}
+	sc->flags |= TPRMARK | TPRANY;
+	wtclock(sc);
+	/* Don't wait for completion here. */
+	return 0;
+}
+
+/*
+ * Write marker to the tape.
+ */
+int
+wtwritefm(sc)
+	struct wt_softc *sc;
+{
+
+	tsleep((caddr_t)wtwritefm, WTPRI, "wtwfm", hz);
+	sc->flags &= ~(TPRO | TPWO);
+	if (!wtcmd(sc, QIC_WRITEFM)) {
+		wtsense(sc, 1, 0);
+		return EIO;
+	}
+	sc->flags |= TPWMARK | TPWANY;
+	wtclock(sc);
+	return wtwait(sc, 0, "wtwfm");
+}
+
+/*
+ * While controller status & mask == bits continue waiting.
+ */
+u_char
+wtpoll(sc, mask, bits)
+	struct wt_softc *sc;
+	int mask, bits;
+{
+	u_char x;
+	int i;
+
+	/* Poll status port, waiting for specified bits. */
+	for (i = 0; i < 1000; ++i) {	/* up to 1 msec */
+		x = inb(sc->STATPORT);
+		if ((x & mask) != bits)
+			return x;
+		delay(1);
+	}
+	for (i = 0; i < 100; ++i) {	/* up to 10 msec */
+		x = inb(sc->STATPORT);
+		if ((x & mask) != bits)
+			return x;
+		delay(100);
+	}
+	for (;;) {			/* forever */
+		x = inb(sc->STATPORT);
+		if ((x & mask) != bits)
+			return x;
+		tsleep((caddr_t)wtpoll, WTPRI, "wtpoll", 1);
+	}
+}
+
+/*
+ * Execute QIC command.
+ */
+int
+wtcmd(sc, cmd)
+	struct wt_softc *sc;
+	int cmd;
+{
+	u_char x;
+	int s;
+
+	DEBUG(("wtcmd() cmd=0x%x\n", cmd));
+	s = splbio();
+	x = wtpoll(sc, sc->BUSY | sc->NOEXCEP, sc->BUSY | sc->NOEXCEP); /* ready? */
+	if ((x & sc->NOEXCEP) == 0) {			/* error */
+		splx(s);
+		return 0;
+	}
+	
+	outb(sc->CMDPORT, cmd);				/* output the command */
+
+	outb(sc->CTLPORT, sc->REQUEST | sc->ONLINE);	/* set request */
+	wtpoll(sc, sc->BUSY, sc->BUSY);			/* wait for ready */
+	outb(sc->CTLPORT, sc->IEN | sc->ONLINE);	/* reset request */
+	wtpoll(sc, sc->BUSY, 0);			/* wait for not ready */
+	splx(s);
+	return 1;
+}
+
+/* wait for the end of i/o, seeking marker or rewind operation */
+int
+wtwait(sc, catch, msg)
+	struct wt_softc *sc;
+	int catch;
+	char *msg;
+{
+	int error;
+
+	DEBUG(("wtwait() `%s'\n", msg));
+	while (sc->flags & (TPACTIVE | TPREW | TPRMARK | TPWMARK))
+		if (error = tsleep((caddr_t)sc, WTPRI | catch, msg, 0))
+			return error;
+	return 0;
+}
+
+/* initialize dma for the i/o operation */
+void
+wtdma(sc)
+	struct wt_softc *sc;
+{
+
+	sc->flags |= TPACTIVE;
+	wtclock(sc);
+
+	if (sc->type == ARCHIVE) {
+		/* Set DMA. */
+		outb(sc->SDMAPORT, 0);
+	}
+
+	if ((sc->dmaflags & B_READ) &&
+	    (sc->dmatotal - sc->dmacount) < sc->bsize) {
+		/* Reading short block; do it through the internal buffer. */
+		isa_dmastart(sc->dmaflags, sc->buf, sc->bsize, sc->chan);
+	} else
+		isa_dmastart(sc->dmaflags, sc->dmavaddr, sc->bsize, sc->chan);
+}
+
+/* start i/o operation */
+int
+wtstart(sc, flag, vaddr, len)
+	struct wt_softc *sc;
+	int flag;
+	void *vaddr;
+	size_t len;
+{
+	u_char x;
+
+	DEBUG(("wtstart()\n"));
+	x = wtpoll(sc, sc->BUSY | sc->NOEXCEP, sc->BUSY | sc->NOEXCEP); /* ready? */
+	if ((x & sc->NOEXCEP) == 0) {
+		sc->flags |= TPEXCEP;	/* error */
+		return 0;
+	}
+	sc->flags &= ~TPEXCEP;		/* clear exception flag */
+	sc->dmavaddr = vaddr;
+	sc->dmatotal = len;
+	sc->dmacount = 0;
+	sc->dmaflags = flag;
+	wtdma(sc);
+	return 1;
+}
+
+/*
+ * Start timer.
+ */
+void
+wtclock(sc)
+	struct wt_softc *sc;
+{
+
+	if (sc->flags & TPTIMER)
+		return;
+	sc->flags |= TPTIMER;
+	/*
+	 * Some controllers seem to lose dma interrupts too often.  To make the
+	 * tape stream we need 1 tick timeout.
+	 */
+	timeout(wttimer, sc, (sc->flags & TPACTIVE) ? 1 : hz);
+}
+
+/*
+ * Simulate an interrupt periodically while i/o is going.
+ * This is necessary in case interrupts get eaten due to
+ * multiple devices on a single IRQ line.
+ */
+void
+wttimer(arg)
+	void *arg;
+{
+	struct wt_softc *sc = (struct wt_softc *)arg;
+	int s;
+
+	sc->flags &= ~TPTIMER;
+	if ((sc->flags & (TPACTIVE | TPREW | TPRMARK | TPWMARK)) == 0)
+		return;
+
+	/* If i/o going, simulate interrupt. */
+	s = splbio();
+	if ((inb(sc->STATPORT) & (sc->BUSY | sc->NOEXCEP)) != (sc->BUSY | sc->NOEXCEP)) {
+		DEBUG(("wttimer() -- "));
+		wtintr(sc);
+	}
+	splx(s);
+
+	/* Restart timer if i/o pending. */
+	if (sc->flags & (TPACTIVE | TPREW | TPRMARK | TPWMARK))
+		wtclock(sc);
+}
+
+/*
+ * Perform QIC-02 and QIC-36 compatible reset sequence.
+ */
+int
+wtreset(sc)
+	struct wt_softc *sc;
+{
+	u_char x;
+	int i;
+
+	outb(sc->CTLPORT, sc->RESET | sc->ONLINE); /* send reset */
+	delay(30);
+	outb(sc->CTLPORT, sc->ONLINE);	/* turn off reset */
+	delay(30);
+
+	/* Read the controller status. */
+	x = inb(sc->STATPORT);
+	if (x == 0xff)			/* no port at this address? */
+		return 0;
+
+	/* Wait 3 sec for reset to complete. Needed for QIC-36 boards? */
+	for (i = 0; i < 3000; ++i) {
+		if ((x & sc->BUSY) == 0 || (x & sc->NOEXCEP) == 0)
+			break;
+		delay(1000);
+		x = inb(sc->STATPORT);
+	}
+	return (x & sc->RESETMASK) == sc->RESETVAL;
+}
+
+/*
+ * Get controller status information.  Return 0 if user i/o request should
+ * receive an i/o error code.
+ */
+int
+wtsense(sc, verbose, ignore)
+	struct wt_softc *sc;
+	int verbose, ignore;
+{
+	char *msg = 0;
+	int error;
+
+	DEBUG(("wtsense() ignore=0x%x\n", ignore));
+	sc->flags &= ~(TPRO | TPWO);
+	if (!wtstatus(sc))
+		return 0;
+	if ((sc->error & TP_ST0) == 0)
+		sc->error &= ~TP_ST0MASK;
+	if ((sc->error & TP_ST1) == 0)
+		sc->error &= ~TP_ST1MASK;
+	sc->error &= ~ignore;	/* ignore certain errors */
+	error = sc->error & (TP_FIL | TP_BNL | TP_UDA | TP_EOM | TP_WRP |
+	    TP_USL | TP_CNI | TP_MBD | TP_NDT | TP_ILL);
+	if (!error)
+		return 1;
+	if (!verbose)
+		return 0;
+
+	/* lifted from tdriver.c from Wangtek */
+	if (error & TP_USL)
+		msg = "Drive not online";
+	else if (error & TP_CNI)
+		msg = "No cartridge";
+	else if ((error & TP_WRP) && (sc->flags & TPWP) == 0) {
+		msg = "Tape is write protected";
+		sc->flags |= TPWP;
+	} else if (error & TP_FIL)
+		msg = 0 /*"Filemark detected"*/;
+	else if (error & TP_EOM)
+		msg = 0 /*"End of tape"*/;
+	else if (error & TP_BNL)
+		msg = "Block not located";
+	else if (error & TP_UDA)
+		msg = "Unrecoverable data error";
+	else if (error & TP_NDT)
+		msg = "No data detected";
+	else if (error & TP_ILL)
+		msg = "Illegal command";
+	if (msg)
+		printf("%s: %s\n", sc->sc_dev.dv_xname, msg);
+	return 0;
+}
+
+/*
+ * Get controller status information.
+ */
+int
+wtstatus(sc)
+	struct wt_softc *sc;
+{
+	char *p;
+	int s;
+
+	s = splbio();
+	wtpoll(sc, sc->BUSY | sc->NOEXCEP, sc->BUSY | sc->NOEXCEP); /* ready? */
+	outb(sc->CMDPORT, QIC_RDSTAT);	/* send `read status' command */
+
+	outb(sc->CTLPORT, sc->REQUEST | sc->ONLINE);	/* set request */
+	wtpoll(sc, sc->BUSY, sc->BUSY);			/* wait for ready */
+	outb(sc->CTLPORT, sc->ONLINE);			/* reset request */
+	wtpoll(sc, sc->BUSY, 0);			/* wait for not ready */
+
+	p = (char *)&sc->error;
+	while (p < (char *)&sc->error + 6) {
+		u_char x = wtpoll(sc, sc->BUSY | sc->NOEXCEP, sc->BUSY | sc->NOEXCEP);
+		if ((x & sc->NOEXCEP) == 0) {	/* error */
+			splx(s);
+			return 0;
+		}
+
+		*p++ = inb(sc->DATAPORT);	/* read status byte */
+
+		outb(sc->CTLPORT, sc->REQUEST | sc->ONLINE); /* set request */
+		wtpoll(sc, sc->BUSY, 0);	/* wait for not ready */
+		outb(sc->CTLPORT, sc->ONLINE);	/* unset request */
+	}
+	splx(s);
+	return 1;
+}