/*      $OpenBSD: fd.c,v 1.55 2025/11/13 20:59:14 deraadt Exp $ */
/*      $NetBSD: fd.c,v 1.112 2003/08/07 16:29:35 agc Exp $     */

/*-
 * Copyright (c) 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by 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.
 */

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Don Ahn.
 *
 * 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. 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.
 *
 *      @(#)fd.c        7.4 (Berkeley) 5/25/91
 */

/*-
 * Copyright (c) 1993, 1994, 1995 Charles M. Hannum.
 * Copyright (c) 1995 Paul Kranenburg.
 *
 * This code is derived from software contributed to Berkeley by
 * Don Ahn.
 *
 * 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.
 *
 *      @(#)fd.c        7.4 (Berkeley) 5/25/91
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/timeout.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/ioctl.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/disklabel.h>
#include <sys/disk.h>
#include <sys/buf.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <sys/mtio.h>
#include <sys/stat.h>
#include <sys/syslog.h>
#include <sys/queue.h>
#include <sys/dkio.h>

#include <dev/cons.h>

#include <uvm/uvm_extern.h>

#include <machine/autoconf.h>
#include <machine/conf.h>
#include <machine/intr.h>
#include <machine/ioctl_fd.h>

#include <sparc64/dev/auxioreg.h>
#include <sparc64/dev/auxiovar.h>
#include <sparc64/dev/ebusreg.h>
#include <sparc64/dev/ebusvar.h>
#include <sparc64/dev/fdreg.h>
#include <sparc64/dev/fdvar.h>

#define FDUNIT(dev)     ((minor(dev) / MAXPARTITIONSUNIT) / 8)
#define FDTYPE(dev)     ((minor(dev) / MAXPARTITIONSUNIT) % 8)
#define FDPART(dev)     (minor(dev) % MAXPARTITIONSUNIT)

#define FTC_FLIP \
        do { \
                auxio_fd_control(AUXIO_LED_FTC); \
                auxio_fd_control(0); \
        } while (0)

/* XXX misuse a flag to identify format operation */
#define B_FORMAT B_XXX

#ifdef FD_DEBUG
int     fdc_debug = 0;
#endif

enum fdc_state {
        DEVIDLE = 0,
        MOTORWAIT,      /*  1 */
        DOSEEK,         /*  2 */
        SEEKWAIT,       /*  3 */
        SEEKTIMEDOUT,   /*  4 */
        SEEKCOMPLETE,   /*  5 */
        DOIO,           /*  6 */
        IOCOMPLETE,     /*  7 */
        IOTIMEDOUT,     /*  8 */
        IOCLEANUPWAIT,  /*  9 */
        IOCLEANUPTIMEDOUT,/*10 */
        DORESET,        /* 11 */
        RESETCOMPLETE,  /* 12 */
        RESETTIMEDOUT,  /* 13 */
        DORECAL,        /* 14 */
        RECALWAIT,      /* 15 */
        RECALTIMEDOUT,  /* 16 */
        RECALCOMPLETE,  /* 17 */
        DODSKCHG,       /* 18 */
        DSKCHGWAIT,     /* 19 */
        DSKCHGTIMEDOUT, /* 20 */
};

/* software state, per controller */
struct fdc_softc {
        struct device   sc_dev;         /* boilerplate */
        bus_space_tag_t sc_bustag;

        struct timeout fdctimeout_to;
        struct timeout fdcpseudointr_to;

        struct fd_softc *sc_fd[4];      /* pointers to children */
        TAILQ_HEAD(drivehead, fd_softc) sc_drives;
        enum fdc_state  sc_state;
        int             sc_flags;
#define FDC_EBUS                0x01
#define FDC_NEEDHEADSETTLE      0x02
#define FDC_EIS                 0x04
#define FDC_NEEDMOTORWAIT       0x08
#define FDC_NOEJECT             0x10
        int             sc_errors;              /* number of retries so far */
        int             sc_overruns;            /* number of DMA overruns */
        int             sc_cfg;                 /* current configuration */
        struct fdcio    sc_io;
#define sc_handle       sc_io.fdcio_handle
#define sc_itask        sc_io.fdcio_itask
#define sc_istatus      sc_io.fdcio_istatus
#define sc_data         sc_io.fdcio_data
#define sc_tc           sc_io.fdcio_tc
#define sc_nstat        sc_io.fdcio_nstat
#define sc_status       sc_io.fdcio_status

        void            *sc_sicookie;   /* softintr(9) cookie */
};

/* controller driver configuration */
int     fdcmatch_sbus(struct device *, void *, void *);
int     fdcmatch_ebus(struct device *, void *, void *);
void    fdcattach_sbus(struct device *, struct device *, void *);
void    fdcattach_ebus(struct device *, struct device *, void *);

int     fdcattach(struct fdc_softc *, int);

const struct cfattach fdc_sbus_ca = {
        sizeof(struct fdc_softc), fdcmatch_sbus, fdcattach_sbus
};

const struct cfattach fdc_ebus_ca = {
        sizeof(struct fdc_softc), fdcmatch_ebus, fdcattach_ebus
};

struct cfdriver fdc_cd = {
        NULL, "fdc", DV_DULL
};

__inline struct fd_type *fd_dev_to_type(struct fd_softc *, dev_t);

/* The order of entries in the following table is important -- BEWARE! */
struct fd_type fd_types[] = {
        { 18,2,36,2,0xff,0xcf,0x1b,0x6c,80,2880,1,FDC_500KBPS, "1.44MB"    }, /* 1.44MB diskette */
        {  9,2,18,2,0xff,0xdf,0x2a,0x50,80,1440,1,FDC_250KBPS, "720KB"    }, /* 3.5" 720kB diskette */
        {  9,2,18,2,0xff,0xdf,0x2a,0x50,40, 720,2,FDC_250KBPS, "360KB/x"  }, /* 360kB in 720kB drive */
        {  8,2,16,3,0xff,0xdf,0x35,0x74,77,1232,1,FDC_500KBPS, "1.2MB/NEC" } /* 1.2 MB japanese format */
};

/* software state, per disk (with up to 4 disks per ctlr) */
struct fd_softc {
        struct device   sc_dv;          /* generic device info */
        struct disk     sc_dk;          /* generic disk info */

        struct fd_type *sc_deftype;     /* default type descriptor */
        struct fd_type *sc_type;        /* current type descriptor */

        struct timeout sc_motoron_to;
        struct timeout sc_motoroff_to;

        daddr_t sc_blkno;       /* starting block number */
        int sc_bcount;          /* byte count left */
        int sc_skip;            /* bytes already transferred */
        int sc_nblks;           /* number of blocks currently transferring */
        int sc_nbytes;          /* number of bytes currently transferring */

        int sc_drive;           /* physical unit number */
        int sc_flags;
#define FD_OPEN         0x01            /* it's open */
#define FD_MOTOR        0x02            /* motor should be on */
#define FD_MOTOR_WAIT   0x04            /* motor coming up */
        int sc_cylin;           /* where we think the head is */
        int sc_opts;            /* user-set options */

        TAILQ_ENTRY(fd_softc) sc_drivechain;
        int sc_ops;             /* I/O ops since last switch */
        struct bufq sc_bufq;    /* pending I/O requests */
        struct buf *sc_bp;      /* current I/O */
};

/* floppy driver configuration */
int     fdmatch(struct device *, void *, void *);
void    fdattach(struct device *, struct device *, void *);
int     fdactivate(struct device *, int);

const struct cfattach fd_ca = {
        sizeof(struct fd_softc), fdmatch, fdattach,
        NULL, fdactivate
};

struct cfdriver fd_cd = {
        NULL, "fd", DV_DISK
};

int fdgetdisklabel(dev_t, struct fd_softc *, struct disklabel *, int);
void fdstrategy(struct buf *);
void fdstart(struct fd_softc *);
int fdprint(void *, const char *);

struct  fd_type *fd_nvtotype(char *, int, int);
void    fd_set_motor(struct fdc_softc *fdc);
void    fd_motor_off(void *arg);
void    fd_motor_on(void *arg);
int     fdcresult(struct fdc_softc *fdc);
int     fdc_wrfifo(struct fdc_softc *fdc, u_char x);
void    fdcstart(struct fdc_softc *fdc);
void    fdcstatus(struct fdc_softc *fdc, char *s);
void    fdc_reset(struct fdc_softc *fdc);
int     fdc_diskchange(struct fdc_softc *fdc);
void    fdctimeout(void *arg);
void    fdcpseudointr(void *arg);
int     fdchwintr(void *);
void    fdcswintr(void *);
int     fdcstate(struct fdc_softc *);
void    fdcretry(struct fdc_softc *fdc);
void    fdfinish(struct fd_softc *fd, struct buf *bp);
int     fdformat(dev_t, struct fd_formb *, struct proc *);
void    fd_do_eject(struct fd_softc *);
static int fdconf(struct fdc_softc *);

int
fdcmatch_sbus(struct device *parent, void *match, void *aux)
{
        struct sbus_attach_args *sa = aux;

        return (strcmp("SUNW,fdtwo", sa->sa_name) == 0);
}

void
fdcattach_sbus(struct device *parent, struct device *self, void *aux)
{
        struct fdc_softc *fdc = (void *)self;
        struct sbus_attach_args *sa = aux;

        if (sa->sa_nintr == 0) {
                printf(": no interrupt line configured\n");
                return;
        }

        if (auxio_fd_control(0) != 0) {
                printf(": can't attach before auxio\n");
                return;
        }

        fdc->sc_bustag = sa->sa_bustag;

        if (sbus_bus_map(sa->sa_bustag,
                         sa->sa_slot, sa->sa_offset, sa->sa_size,
                         BUS_SPACE_MAP_LINEAR, 0, &fdc->sc_handle) != 0) {
                printf(": cannot map control registers\n");
                return;
        }

        if (strcmp(getpropstring(sa->sa_node, "status"), "disabled") == 0) {
                printf(": no drives attached\n");
                return;
        }

        if (getproplen(sa->sa_node, "manual") >= 0)
                fdc->sc_flags |= FDC_NOEJECT;

        if (fdcattach(fdc, sa->sa_pri) != 0)
                bus_space_unmap(sa->sa_bustag, fdc->sc_handle, sa->sa_size);
}

int
fdcmatch_ebus(struct device *parent, void *match, void *aux)
{
        struct ebus_attach_args *ea = aux;

        return (strcmp("fdthree", ea->ea_name) == 0);
}

void
fdcattach_ebus(struct device *parent, struct device *self, void *aux)
{
        struct fdc_softc *fdc = (void *)self;
        struct ebus_attach_args *ea = aux;

        if (ea->ea_nintrs == 0) {
                printf(": no interrupt line configured\n");
                return;
        }

        if (ea->ea_nregs < 3) {
                printf(": expected 3 registers, only got %d\n",
                    ea->ea_nregs);
                return;
        }

        if (ea->ea_nvaddrs > 0) {
                if (bus_space_map(ea->ea_memtag, ea->ea_vaddrs[0], 0,
                    BUS_SPACE_MAP_PROMADDRESS, &fdc->sc_handle) != 0) {
                        printf(": can't map control registers\n");
                        return;
                }
                fdc->sc_bustag = ea->ea_memtag;
        } else if (ebus_bus_map(ea->ea_memtag, 0,
            EBUS_PADDR_FROM_REG(&ea->ea_regs[0]),
            ea->ea_regs[0].size, 0, 0, &fdc->sc_handle) == 0) {
                fdc->sc_bustag = ea->ea_memtag;
        } else if (ebus_bus_map(ea->ea_iotag, 0,
            EBUS_PADDR_FROM_REG(&ea->ea_regs[0]),
            ea->ea_regs[0].size, 0, 0, &fdc->sc_handle) == 0) {
                fdc->sc_bustag = ea->ea_iotag;
        } else {
                printf(": can't map control registers\n");
                return;
        }

        if (strcmp(getpropstring(ea->ea_node, "status"), "disabled") == 0) {
                printf(": no drives attached\n");
                return;
        }

        fdc->sc_flags |= FDC_EBUS;

        if (getproplen(ea->ea_node, "manual") >= 0)
                fdc->sc_flags |= FDC_NOEJECT;

        /* XXX unmapping if it fails */
        fdcattach(fdc, ea->ea_intrs[0]);
}

/*
 * Arguments passed between fdcattach and fdprobe.
 */
struct fdc_attach_args {
        int fa_drive;
        struct fd_type *fa_deftype;
};

/*
 * Print the location of a disk drive (called just before attaching the
 * the drive).  If `fdc' is not NULL, the drive was found but was not
 * in the system config file; print the drive name as well.
 * Return QUIET (config_find ignores this if the device was configured) to
 * avoid printing `fdN not configured' messages.
 */
int
fdprint(void *aux, const char *fdc)
{
        register struct fdc_attach_args *fa = aux;

        if (!fdc)
                printf(" drive %d", fa->fa_drive);
        return (QUIET);
}

/*
 * Configure several parameters and features on the FDC.
 * Return 0 on success.
 */
static int
fdconf(struct fdc_softc *fdc)
{
        int     vroom;

        if (fdc_wrfifo(fdc, NE7CMD_DUMPREG) || fdcresult(fdc) != 10)
                return (-1);

        /*
         * dumpreg[7] seems to be a motor-off timeout; set it to whatever
         * the PROM thinks is appropriate.
         */
        if ((vroom = fdc->sc_status[7]) == 0)
                vroom = 0x64;

        /* Configure controller to use FIFO and Implied Seek */
        if (fdc_wrfifo(fdc, NE7CMD_CFG) != 0)
                return (-1);
        if (fdc_wrfifo(fdc, vroom) != 0)
                return (-1);
        if (fdc_wrfifo(fdc, fdc->sc_cfg) != 0)
                return (-1);
        if (fdc_wrfifo(fdc, 0) != 0)    /* PRETRK */
                return (-1);
        /* No result phase for the NE7CMD_CFG command */

        /* Lock configuration across soft resets. */
        if (fdc_wrfifo(fdc, NE7CMD_LOCK | CFG_LOCK) != 0 ||
            fdcresult(fdc) != 1) {
#ifdef FD_DEBUG
                printf("fdconf: CFGLOCK failed");
#endif
                return (-1);
        }

        return (0);
#if 0
        if (fdc_wrfifo(fdc, NE7CMD_VERSION) == 0 &&
            fdcresult(fdc) == 1 && fdc->sc_status[0] == 0x90) {
                if (fdc_debug)
                        printf("[version cmd]");
        }
#endif
}

int
fdcattach(struct fdc_softc *fdc, int pri)
{
        struct fdc_attach_args fa;
        int drive_attached;

        timeout_set(&fdc->fdctimeout_to, fdctimeout, fdc);
        timeout_set(&fdc->fdcpseudointr_to, fdcpseudointr, fdc);

        fdc->sc_state = DEVIDLE;
        fdc->sc_itask = FDC_ITASK_NONE;
        fdc->sc_istatus = FDC_ISTATUS_NONE;
        fdc->sc_flags |= FDC_EIS | FDC_NEEDMOTORWAIT;
        TAILQ_INIT(&fdc->sc_drives);

        /*
         * Configure controller; enable FIFO, Implied seek, no POLL mode?.
         * Note: CFG_EFIFO is active-low, initial threshold value: 8
         */
        fdc->sc_cfg = CFG_EIS|/*CFG_EFIFO|*/CFG_POLL|(8 & CFG_THRHLD_MASK);
        if (fdconf(fdc) != 0) {
                printf("\n%s: no drives attached\n", fdc->sc_dev.dv_xname);
                return (-1);
        }

        if (bus_intr_establish(fdc->sc_bustag, pri, IPL_BIO,
            0, fdchwintr, fdc, fdc->sc_dev.dv_xname) == NULL) {
                printf("\n%s: cannot register interrupt handler\n",
                        fdc->sc_dev.dv_xname);
                return (-1);
        }

        fdc->sc_sicookie = softintr_establish_raw(IPL_BIO, fdcswintr, fdc);
        if (fdc->sc_sicookie == NULL) {
                printf("\n%s: cannot register soft interrupt handler\n",
                        fdc->sc_dev.dv_xname);
                return (-1);
        }

        if (fdc->sc_flags & FDC_NOEJECT)
                printf(": manual eject");
        printf("\n");

        /* physical limit: four drives per controller. */
        drive_attached = 0;
        for (fa.fa_drive = 0; fa.fa_drive < 4; fa.fa_drive++) {
                fa.fa_deftype = NULL;           /* unknown */
                fa.fa_deftype = &fd_types[0];   /* XXX */
                if (config_found(&fdc->sc_dev, (void *)&fa, fdprint) != NULL)
                        drive_attached = 1;
        }

        if (drive_attached == 0) {
                /* XXX - dis-establish interrupts here */
                /* return (-1); */
        }

        return (0);
}

int
fdmatch(struct device *parent, void *match, void *aux)
{
        struct fdc_softc *fdc = (void *)parent;
        bus_space_tag_t t = fdc->sc_bustag;
        bus_space_handle_t h = fdc->sc_handle;
        struct fdc_attach_args *fa = aux;
        int drive = fa->fa_drive;
        int n, ok;

        if (drive > 0)
                /* XXX - for now, punt on more than one drive */
                return (0);

        /* select drive and turn on motor */
        bus_space_write_1(t, h, FDREG77_DOR,
            drive | FDO_FRST | FDO_MOEN(drive));
        /* wait for motor to spin up */
        delay(250000);

        fdc->sc_nstat = 0;
        fdc_wrfifo(fdc, NE7CMD_RECAL);
        fdc_wrfifo(fdc, drive);

        /* Wait for recalibration to complete */
        for (n = 0; n < 10000; n++) {
                u_int8_t v;

                delay(1000);
                v = bus_space_read_1(t, h, FDREG77_MSR);
                if ((v & (NE7_RQM|NE7_DIO|NE7_CB)) == NE7_RQM) {
                        /* wait a bit longer till device *really* is ready */
                        delay(100000);
                        if (fdc_wrfifo(fdc, NE7CMD_SENSEI))
                                break;
                        if (fdcresult(fdc) == 1 && fdc->sc_status[0] == 0x80)
                                /*
                                 * Got `invalid command'; we interpret it
                                 * to mean that the re-calibrate hasn't in
                                 * fact finished yet
                                 */
                                continue;
                        break;
                }
        }
        n = fdc->sc_nstat;
#ifdef FD_DEBUG
        if (fdc_debug) {
                int i;
                printf("fdprobe: %d stati:", n);
                for (i = 0; i < n; i++)
                        printf(" 0x%x", fdc->sc_status[i]);
                printf("\n");
        }
#endif
        ok = (n == 2 && (fdc->sc_status[0] & 0xf8) == 0x20) ? 1 : 0;

        /* deselect drive and turn motor off */
        bus_space_write_1(t, h, FDREG77_DOR, FDO_FRST | FDO_DS);

        return (ok);
}

/*
 * Controller is working, and drive responded.  Attach it.
 */
void
fdattach(struct device *parent, struct device *self, void *aux)
{
        struct fdc_softc *fdc = (void *)parent;
        struct fd_softc *fd = (void *)self;
        struct fdc_attach_args *fa = aux;
        struct fd_type *type = fa->fa_deftype;
        int drive = fa->fa_drive;

        timeout_set(&fd->sc_motoron_to, fd_motor_on, fd);
        timeout_set(&fd->sc_motoroff_to, fd_motor_off, fd);

        /* XXX Allow `flags' to override device type? */

        if (type)
                printf(": %s %d cyl, %d head, %d sec\n", type->name,
                    type->tracks, type->heads, type->sectrac);
        else
                printf(": density unknown\n");

        fd->sc_cylin = -1;
        fd->sc_drive = drive;
        fd->sc_deftype = type;
        fdc->sc_fd[drive] = fd;

        fdc_wrfifo(fdc, NE7CMD_SPECIFY);
        fdc_wrfifo(fdc, type->steprate);
        /* XXX head load time == 6ms */
        fdc_wrfifo(fdc, 6 | NE7_SPECIFY_NODMA);

        /*
         * Initialize and attach the disk structure.
         */
        fd->sc_dk.dk_flags = DKF_NOLABELREAD;
        fd->sc_dk.dk_name = fd->sc_dv.dv_xname;
        bufq_init(&fd->sc_bufq, BUFQ_DEFAULT);
        disk_attach(&fd->sc_dv, &fd->sc_dk);
}

int
fdactivate(struct device *self, int act)
{
        int ret = 0;

        switch (act) {
        case DVACT_POWERDOWN:
                /* Make sure the drive motor gets turned off at shutdown time. */
                fd_motor_off(self);
                break;
        }

        return (ret);
}

__inline struct fd_type *
fd_dev_to_type(struct fd_softc *fd, dev_t dev)
{
        int type = FDTYPE(dev);

        if (type > (sizeof(fd_types) / sizeof(fd_types[0])))
                return (NULL);
        return (type ? &fd_types[type - 1] : fd->sc_deftype);
}

void
fdstrategy(struct buf *bp)
{
        struct fd_softc *fd;
        int unit = FDUNIT(bp->b_dev);
        int sz;
        int s;

        /* Valid unit, controller, and request? */
        if (unit >= fd_cd.cd_ndevs ||
            (fd = fd_cd.cd_devs[unit]) == 0 ||
            bp->b_blkno < 0 ||
            (((bp->b_bcount % FD_BSIZE(fd)) != 0 ||
              (bp->b_blkno * DEV_BSIZE) % FD_BSIZE(fd) != 0) &&
             (bp->b_flags & B_FORMAT) == 0)) {
                bp->b_error = EINVAL;
                goto bad;
        }

        /* If it's a null transfer, return immediately. */
        if (bp->b_bcount == 0)
                goto done;

        bp->b_resid = bp->b_bcount;
        sz = howmany(bp->b_bcount, DEV_BSIZE);

        if (bp->b_blkno + sz > (fd->sc_type->size * DEV_BSIZE) / FD_BSIZE(fd)) {
                sz = (fd->sc_type->size * DEV_BSIZE) / FD_BSIZE(fd)
                     - bp->b_blkno;
                if (sz == 0) {
                        /* If exactly at end of disk, return EOF. */
                        goto done;
                }
                if (sz < 0) {
                        /* If past end of disk, return EINVAL. */
                        bp->b_error = EINVAL;
                        goto bad;
                }
                /* Otherwise, truncate request. */
                bp->b_bcount = sz << DEV_BSHIFT;
        }

#ifdef FD_DEBUG
        if (fdc_debug > 1)
            printf("fdstrategy: b_blkno %lld b_bcount %d blkno %lld\n",
                    (long long)bp->b_blkno, bp->b_bcount,
                    (long long)fd->sc_blkno);
#endif

        /* Queue transfer */
        bufq_queue(&fd->sc_bufq, bp);

        /* Queue transfer on drive, activate drive and controller if idle. */
        s = splbio();
        timeout_del(&fd->sc_motoroff_to);               /* a good idea */
        if (fd->sc_bp == NULL)
                fdstart(fd);
#ifdef DIAGNOSTIC
        else {
                struct fdc_softc *fdc = (void *)fd->sc_dv.dv_parent;
                if (fdc->sc_state == DEVIDLE) {
                        printf("fdstrategy: controller inactive\n");
                        fdcstart(fdc);
                }
        }
#endif
        splx(s);
        return;

bad:
        bp->b_flags |= B_ERROR;
done:
        /* Toss transfer; we're done early. */
        s = splbio();
        biodone(bp);
        splx(s);
}

void
fdstart(struct fd_softc *fd)
{
        struct fdc_softc *fdc = (void *)fd->sc_dv.dv_parent;
        int active = !TAILQ_EMPTY(&fdc->sc_drives);

        /* Link into controller queue. */
        fd->sc_bp = bufq_dequeue(&fd->sc_bufq);
        TAILQ_INSERT_TAIL(&fdc->sc_drives, fd, sc_drivechain);

        /* If controller not already active, start it. */
        if (!active)
                fdcstart(fdc);
}

void
fdfinish(struct fd_softc *fd, struct buf *bp)
{
        struct fdc_softc *fdc = (void *)fd->sc_dv.dv_parent;

        fd->sc_skip = 0;
        fd->sc_bp = bufq_dequeue(&fd->sc_bufq);

        /*
         * Move this drive to the end of the queue to give others a `fair'
         * chance.  We only force a switch if N operations are completed while
         * another drive is waiting to be serviced, since there is a long motor
         * startup delay whenever we switch.
         */
        if (TAILQ_NEXT(fd, sc_drivechain) != NULL && ++fd->sc_ops >= 8) {
                fd->sc_ops = 0;
                TAILQ_REMOVE(&fdc->sc_drives, fd, sc_drivechain);
                if (fd->sc_bp != NULL)
                        TAILQ_INSERT_TAIL(&fdc->sc_drives, fd, sc_drivechain);
        }

        biodone(bp);
        /* turn off motor 5s from now */
        timeout_add_sec(&fd->sc_motoroff_to, 5);
        fdc->sc_state = DEVIDLE;
}

void
fdc_reset(struct fdc_softc *fdc)
{
        bus_space_tag_t t = fdc->sc_bustag;
        bus_space_handle_t h = fdc->sc_handle;

        bus_space_write_1(t, h, FDREG77_DOR, FDO_FDMAEN | FDO_MOEN(0));

        bus_space_write_1(t, h, FDREG77_DRS, DRS_RESET);
        delay(10);
        bus_space_write_1(t, h, FDREG77_DRS, 0);

        bus_space_write_1(t, h, FDREG77_DOR,
            FDO_FRST | FDO_FDMAEN | FDO_DS);
#ifdef FD_DEBUG
        if (fdc_debug)
                printf("fdc reset\n");
#endif
}

void
fd_set_motor(struct fdc_softc *fdc)
{
        struct fd_softc *fd;
        u_char status;
        int n;

        status = FDO_FRST | FDO_FDMAEN;
        if ((fd = TAILQ_FIRST(&fdc->sc_drives)) != NULL)
                status |= fd->sc_drive;

        for (n = 0; n < 4; n++)
                if ((fd = fdc->sc_fd[n]) && (fd->sc_flags & FD_MOTOR))
                        status |= FDO_MOEN(n);
        bus_space_write_1(fdc->sc_bustag, fdc->sc_handle,
            FDREG77_DOR, status);
}

void
fd_motor_off(void *arg)
{
        struct fd_softc *fd = arg;
        int s;

        s = splbio();
        fd->sc_flags &= ~(FD_MOTOR | FD_MOTOR_WAIT);
        fd_set_motor((struct fdc_softc *)fd->sc_dv.dv_parent);
        splx(s);
}

void
fd_motor_on(void *arg)
{
        struct fd_softc *fd = arg;
        struct fdc_softc *fdc = (void *)fd->sc_dv.dv_parent;
        int s;

        s = splbio();
        fd->sc_flags &= ~FD_MOTOR_WAIT;
        if (fd == TAILQ_FIRST(&fdc->sc_drives) && fdc->sc_state == MOTORWAIT)
                (void) fdcstate(fdc);
        splx(s);
}

/*
 * Get status bytes off the FDC after a command has finished
 * Returns the number of status bytes read; -1 on error.
 * The return value is also stored in `sc_nstat'.
 */
int
fdcresult(struct fdc_softc *fdc)
{
        bus_space_tag_t t = fdc->sc_bustag;
        bus_space_handle_t h = fdc->sc_handle;
        int j, n = 0;

        for (j = 100000; j; j--) {
                u_int8_t v = bus_space_read_1(t, h, FDREG77_MSR);
                v &= (NE7_DIO | NE7_RQM | NE7_CB);
                if (v == NE7_RQM)
                        return (fdc->sc_nstat = n);
                if (v == (NE7_DIO | NE7_RQM | NE7_CB)) {
                        if (n >= sizeof(fdc->sc_status)) {
                                log(LOG_ERR, "fdcresult: overrun\n");
                                return (-1);
                        }
                        fdc->sc_status[n++] =
                            bus_space_read_1(t, h, FDREG77_FIFO);
                } else
                        delay(1);
        }

        log(LOG_ERR, "fdcresult: timeout\n");
        return (fdc->sc_nstat = -1);
}

/*
 * Write a command byte to the FDC.
 * Returns 0 on success; -1 on failure (i.e. timeout)
 */
int
fdc_wrfifo(struct fdc_softc *fdc, u_int8_t x)
{
        bus_space_tag_t t = fdc->sc_bustag;
        bus_space_handle_t h = fdc->sc_handle;
        int i;

        for (i = 100000; i-- != 0;) {
                u_int8_t v = bus_space_read_1(t, h, FDREG77_MSR);
                if ((v & (NE7_DIO|NE7_RQM)) == NE7_RQM) {
                        /* The chip is ready */
                        bus_space_write_1(t, h, FDREG77_FIFO, x);
                        return (0);
                }
                delay(1);
        }
        return (-1);
}

int
fdc_diskchange(struct fdc_softc *fdc)
{
        bus_space_tag_t t = fdc->sc_bustag;
        bus_space_handle_t h = fdc->sc_handle;

        u_int8_t v = bus_space_read_1(t, h, FDREG77_DIR);
        return ((v & FDI_DCHG) != 0);
}

int
fdopen(dev_t dev, int flags, int fmt, struct proc *p)
{
        int unit, pmask;
        struct fd_softc *fd;
        struct fd_type *type;

        unit = FDUNIT(dev);
        if (unit >= fd_cd.cd_ndevs)
                return (ENXIO);
        fd = fd_cd.cd_devs[unit];
        if (fd == NULL)
                return (ENXIO);
        type = fd_dev_to_type(fd, dev);
        if (type == NULL)
                return (ENXIO);

        if ((fd->sc_flags & FD_OPEN) != 0 &&
            fd->sc_type != type)
                return (EBUSY);

        fd->sc_type = type;
        fd->sc_cylin = -1;
        fd->sc_flags |= FD_OPEN;

        /*
         * Only update the disklabel if we're not open anywhere else.
         */
        if (fd->sc_dk.dk_openmask == 0)
                fdgetdisklabel(dev, fd, fd->sc_dk.dk_label, 0);

        pmask = (1 << FDPART(dev));

        switch (fmt) {
        case S_IFCHR:
                fd->sc_dk.dk_copenmask |= pmask;
                break;

        case S_IFBLK:
                fd->sc_dk.dk_bopenmask |= pmask;
                break;
        }
        fd->sc_dk.dk_openmask =
            fd->sc_dk.dk_copenmask | fd->sc_dk.dk_bopenmask;

        return (0);
}

int
fdclose(dev_t dev, int flags, int fmt, struct proc *p)
{
        struct fd_softc *fd = fd_cd.cd_devs[FDUNIT(dev)];
        int pmask = (1 << FDPART(dev));

        fd->sc_flags &= ~FD_OPEN;
        fd->sc_opts &= ~(FDOPT_NORETRY|FDOPT_SILENT);

        switch (fmt) {
        case S_IFCHR:
                fd->sc_dk.dk_copenmask &= ~pmask;
                break;

        case S_IFBLK:
                fd->sc_dk.dk_bopenmask &= ~pmask;
                break;
        }
        fd->sc_dk.dk_openmask =
            fd->sc_dk.dk_copenmask | fd->sc_dk.dk_bopenmask;

        return (0);
}

int
fdread(dev_t dev, struct uio *uio, int flag)
{

        return (physio(fdstrategy, dev, B_READ, minphys, uio));
}

int
fdwrite(dev_t dev, struct uio *uio, int flag)
{

        return (physio(fdstrategy, dev, B_WRITE, minphys, uio));
}

void
fdcstart(struct fdc_softc *fdc)
{

#ifdef DIAGNOSTIC
        /* only got here if controller's drive queue was inactive; should
           be in idle state */
        if (fdc->sc_state != DEVIDLE) {
                printf("fdcstart: not idle\n");
                return;
        }
#endif
        (void) fdcstate(fdc);
}

void
fdcstatus(struct fdc_softc *fdc, char *s)
{
        struct fd_softc *fd = TAILQ_FIRST(&fdc->sc_drives);
        int n;

        /* Just print last status */
        n = fdc->sc_nstat;

#if 0
        if (n == 0) {
                fdc_wrfifo(fdc, NE7CMD_SENSEI);
                (void) fdcresult(fdc);
                n = 2;
        }
#endif

        printf("%s: %s: state %d",
                fd ? fd->sc_dv.dv_xname : "fdc", s, fdc->sc_state);

        switch (n) {
        case 0:
                printf("\n");
                break;
        case 2:
                printf(" (st0 %b cyl %d)\n",
                    fdc->sc_status[0], NE7_ST0BITS,
                    fdc->sc_status[1]);
                break;
        case 7:
                printf(" (st0 %b st1 %b st2 %b cyl %d head %d sec %d)\n",
                    fdc->sc_status[0], NE7_ST0BITS,
                    fdc->sc_status[1], NE7_ST1BITS,
                    fdc->sc_status[2], NE7_ST2BITS,
                    fdc->sc_status[3], fdc->sc_status[4], fdc->sc_status[5]);
                break;
#ifdef DIAGNOSTIC
        default:
                printf(" fdcstatus: weird size: %d\n", n);
                break;
#endif
        }
}

void
fdctimeout(void *arg)
{
        struct fdc_softc *fdc = arg;
        struct fd_softc *fd;
        int s;

        s = splbio();
        fd = TAILQ_FIRST(&fdc->sc_drives);
        if (fd == NULL) {
                printf("%s: timeout but no I/O pending: state %d, istatus=%d\n",
                    fdc->sc_dev.dv_xname, fdc->sc_state, fdc->sc_istatus);
                fdc->sc_state = DEVIDLE;
                goto out;
        }

        if (fd->sc_bp != NULL)
                fdc->sc_state++;
        else
                fdc->sc_state = DEVIDLE;

        (void) fdcstate(fdc);
out:
        splx(s);

}

void
fdcpseudointr(void *arg)
{
        struct fdc_softc *fdc = arg;
        int s;

        /* Just ensure it has the right spl. */
        s = splbio();
        (void) fdcstate(fdc);
        splx(s);
}


/*
 * Hardware interrupt entry point.
 * Unfortunately, we have no reliable way to determine that the
 * interrupt really came from the floppy controller; just hope
 * that the other devices that share this interrupt can do better..
 */
int
fdchwintr(void *arg)
{
        struct fdc_softc *fdc = arg;
        bus_space_tag_t t = fdc->sc_bustag;
        bus_space_handle_t h = fdc->sc_handle;

        switch (fdc->sc_itask) {
        case FDC_ITASK_NONE:
                return (0);
        case FDC_ITASK_SENSEI:
                if (fdc_wrfifo(fdc, NE7CMD_SENSEI) != 0 || fdcresult(fdc) == -1)
                        fdc->sc_istatus = FDC_ISTATUS_ERROR;
                else
                        fdc->sc_istatus = FDC_ISTATUS_DONE;
                softintr_schedule_raw(fdc->sc_sicookie);
                return (1);
        case FDC_ITASK_RESULT:
                if (fdcresult(fdc) == -1)
                        fdc->sc_istatus = FDC_ISTATUS_ERROR;
                else
                        fdc->sc_istatus = FDC_ISTATUS_DONE;
                softintr_schedule_raw(fdc->sc_sicookie);
                return (1);
        case FDC_ITASK_DMA:
                /* Proceed with pseudo-DMA below */
                break;
        default:
                printf("fdc: stray hard interrupt: itask=%d\n", fdc->sc_itask);
                fdc->sc_istatus = FDC_ISTATUS_SPURIOUS;
                softintr_schedule_raw(fdc->sc_sicookie);
                return (1);
        }

        /*
         * Pseudo DMA in progress
         */
        for (;;) {
                u_int8_t msr;

                msr = bus_space_read_1(t, h, FDREG77_MSR);

                if ((msr & NE7_RQM) == 0)
                        /* That's all this round */
                        break;

                if ((msr & NE7_NDM) == 0) {
                        fdcresult(fdc);
                        fdc->sc_istatus = FDC_ISTATUS_DONE;
                        softintr_schedule_raw(fdc->sc_sicookie);
#ifdef FD_DEBUG
                        if (fdc_debug > 1)
                                printf("fdc: overrun: msr = %x, tc = %d\n",
                                    msr, fdc->sc_tc);
#endif
                        break;
                }

                /* Another byte can be transferred */
                if ((msr & NE7_DIO) != 0)
                        *fdc->sc_data =
                             bus_space_read_1(t, h, FDREG77_FIFO);
                else
                        bus_space_write_1(t, h, FDREG77_FIFO,
                            *fdc->sc_data);

                fdc->sc_data++;
                if (--fdc->sc_tc == 0) {
                        fdc->sc_istatus = FDC_ISTATUS_DONE;
                        FTC_FLIP;
                        fdcresult(fdc);
                        softintr_schedule_raw(fdc->sc_sicookie);
                        break;
                }
        }
        return (1);
}

void
fdcswintr(void *arg)
{
        struct fdc_softc *fdc = arg;
        int s;

        if (fdc->sc_istatus == FDC_ISTATUS_NONE)
                /* This (software) interrupt is not for us */
                return;

        switch (fdc->sc_istatus) {
        case FDC_ISTATUS_ERROR:
                printf("fdc: ierror status: state %d\n", fdc->sc_state);
                break;
        case FDC_ISTATUS_SPURIOUS:
                printf("fdc: spurious interrupt: state %d\n", fdc->sc_state);
                break;
        }

        s = splbio();
        fdcstate(fdc);
        splx(s);
        return;
}

int
fdcstate(struct fdc_softc *fdc)
{
#define st0     fdc->sc_status[0]
#define st1     fdc->sc_status[1]
#define cyl     fdc->sc_status[1]
#define FDC_WRFIFO(fdc, c) \
        do {                                            \
                if (fdc_wrfifo(fdc, (c))) {             \
                        goto xxx;                       \
                }                                       \
        } while(0)

        struct fd_softc *fd;
        struct buf *bp;
        int read, head, sec, nblks, cylin;
        struct fd_type *type;
        struct fd_formb *finfo = NULL;

        if (fdc->sc_istatus == FDC_ISTATUS_ERROR) {
                /* Prevent loop if the reset sequence produces errors */
                if (fdc->sc_state != RESETCOMPLETE &&
                    fdc->sc_state != RECALWAIT &&
                    fdc->sc_state != RECALCOMPLETE)
                        fdc->sc_state = DORESET;
        }

        /* Clear I task/status field */
        fdc->sc_istatus = FDC_ISTATUS_NONE;
        fdc->sc_itask = FDC_ITASK_NONE;

loop:
        /* Is there a drive for the controller to do a transfer with? */
        fd = TAILQ_FIRST(&fdc->sc_drives);
        if (fd == NULL) {
                fdc->sc_state = DEVIDLE;
                return (0);
        }

        /* Is there a transfer to this drive?  If not, deactivate drive. */
        bp = fd->sc_bp;
        if (bp == NULL) {
                fd->sc_ops = 0;
                TAILQ_REMOVE(&fdc->sc_drives, fd, sc_drivechain);
                goto loop;
        }

        if (bp->b_flags & B_FORMAT)
                finfo = (struct fd_formb *)bp->b_data;

        cylin = ((bp->b_blkno * DEV_BSIZE) - (bp->b_bcount - bp->b_resid)) /
            (FD_BSIZE(fd) * fd->sc_type->seccyl);

        switch (fdc->sc_state) {
        case DEVIDLE:
                fdc->sc_errors = 0;
                fd->sc_skip = 0;
                fd->sc_bcount = bp->b_bcount;
                fd->sc_blkno = (bp->b_blkno * DEV_BSIZE) / FD_BSIZE(fd);
                timeout_del(&fd->sc_motoroff_to);
                if ((fd->sc_flags & FD_MOTOR_WAIT) != 0) {
                        fdc->sc_state = MOTORWAIT;
                        return (1);
                }
                if ((fd->sc_flags & FD_MOTOR) == 0) {
                        /* Turn on the motor, being careful about pairing. */
                        struct fd_softc *ofd = fdc->sc_fd[fd->sc_drive ^ 1];
                        if (ofd && ofd->sc_flags & FD_MOTOR) {
                                timeout_del(&ofd->sc_motoroff_to);
                                ofd->sc_flags &= ~(FD_MOTOR | FD_MOTOR_WAIT);
                        }
                        fd->sc_flags |= FD_MOTOR | FD_MOTOR_WAIT;
                        fd_set_motor(fdc);
                        fdc->sc_state = MOTORWAIT;
                        if ((fdc->sc_flags & FDC_NEEDMOTORWAIT) != 0) { /*XXX*/
                                /* Allow .25s for motor to stabilize. */
                                timeout_add_msec(&fd->sc_motoron_to, 250);
                        } else {
                                fd->sc_flags &= ~FD_MOTOR_WAIT;
                                goto loop;
                        }
                        return (1);
                }
                /* Make sure the right drive is selected. */
                fd_set_motor(fdc);

                if (fdc_diskchange(fdc))
                        goto dodskchg;

                /*FALLTHROUGH*/
        case DOSEEK:
        doseek:
                if ((fdc->sc_flags & FDC_EIS) &&
                    (bp->b_flags & B_FORMAT) == 0) {
                        fd->sc_cylin = cylin;
                        /* We use implied seek */
                        goto doio;
                }

                if (fd->sc_cylin == cylin)
                        goto doio;

                fd->sc_cylin = -1;
                fdc->sc_state = SEEKWAIT;
                fdc->sc_nstat = 0;

                fd->sc_dk.dk_seek++;

                disk_busy(&fd->sc_dk);
                timeout_add_sec(&fdc->fdctimeout_to, 4);

                /* specify command */
                FDC_WRFIFO(fdc, NE7CMD_SPECIFY);
                FDC_WRFIFO(fdc, fd->sc_type->steprate);
                /* XXX head load time == 6ms */
                FDC_WRFIFO(fdc, 6 | NE7_SPECIFY_NODMA);

                fdc->sc_itask = FDC_ITASK_SENSEI;
                /* seek function */
                FDC_WRFIFO(fdc, NE7CMD_SEEK);
                FDC_WRFIFO(fdc, fd->sc_drive); /* drive number */
                FDC_WRFIFO(fdc, cylin * fd->sc_type->step);
                return (1);

        case DODSKCHG:
        dodskchg:
                /*
                 * Disk change: force a seek operation by going to cyl 1
                 * followed by a recalibrate.
                 */
                disk_busy(&fd->sc_dk);
                timeout_add_sec(&fdc->fdctimeout_to, 4);
                fd->sc_cylin = -1;
                fdc->sc_nstat = 0;
                fdc->sc_state = DSKCHGWAIT;

                fdc->sc_itask = FDC_ITASK_SENSEI;
                /* seek function */
                FDC_WRFIFO(fdc, NE7CMD_SEEK);
                FDC_WRFIFO(fdc, fd->sc_drive); /* drive number */
                FDC_WRFIFO(fdc, 1 * fd->sc_type->step);
                return (1);

        case DSKCHGWAIT:
                timeout_del(&fdc->fdctimeout_to);
                disk_unbusy(&fd->sc_dk, 0, 0, 0);
                if (fdc->sc_nstat != 2 || (st0 & 0xf8) != 0x20 ||
                    cyl != 1 * fd->sc_type->step) {
                        fdcstatus(fdc, "dskchg seek failed");
                        fdc->sc_state = DORESET;
                } else
                        fdc->sc_state = DORECAL;

                if (fdc_diskchange(fdc)) {
                        printf("%s: cannot clear disk change status\n",
                                fdc->sc_dev.dv_xname);
                        fdc->sc_state = DORESET;
                }
                goto loop;

        case DOIO:
        doio:
                if (finfo != NULL)
                        fd->sc_skip = (char *)&(finfo->fd_formb_cylno(0)) -
                                      (char *)finfo;
                type = fd->sc_type;
                sec = fd->sc_blkno % type->seccyl;
                nblks = type->seccyl - sec;
                nblks = min(nblks, fd->sc_bcount / FD_BSIZE(fd));
                nblks = min(nblks, FDC_MAXIOSIZE / FD_BSIZE(fd));
                fd->sc_nblks = nblks;
                fd->sc_nbytes = finfo ? bp->b_bcount : nblks * FD_BSIZE(fd);
                head = sec / type->sectrac;
                sec -= head * type->sectrac;
#ifdef DIAGNOSTIC
                {
                        daddr_t block;

                        block = (fd->sc_cylin * type->heads + head) *
                            type->sectrac + sec;
                        if (block != fd->sc_blkno) {
                                printf("fdcintr: block %lld != blkno %lld\n",
                                    (long long)block, (long long)fd->sc_blkno);
#if defined(FD_DEBUG) && defined(DDB)
                                 db_enter();
#endif
                        }
                }
#endif
                read = bp->b_flags & B_READ;

                /* Setup for pseudo DMA */
                fdc->sc_data = bp->b_data + fd->sc_skip;
                fdc->sc_tc = fd->sc_nbytes;

                bus_space_write_1(fdc->sc_bustag, fdc->sc_handle,
                    FDREG77_DRS, type->rate);
#ifdef FD_DEBUG
                if (fdc_debug > 1)
                        printf("fdcstate: doio: %s drive %d "
                                "track %d head %d sec %d nblks %d\n",
                                finfo ? "format" :
                                        (read ? "read" : "write"),
                                fd->sc_drive, fd->sc_cylin, head, sec, nblks);
#endif
                fdc->sc_state = IOCOMPLETE;
                fdc->sc_itask = FDC_ITASK_DMA;
                fdc->sc_nstat = 0;

                disk_busy(&fd->sc_dk);

                /* allow 3 seconds for operation */
                timeout_add_sec(&fdc->fdctimeout_to, 3);

                if (finfo != NULL) {
                        /* formatting */
                        FDC_WRFIFO(fdc, NE7CMD_FORMAT);
                        FDC_WRFIFO(fdc, (head << 2) | fd->sc_drive);
                        FDC_WRFIFO(fdc, finfo->fd_formb_secshift);
                        FDC_WRFIFO(fdc, finfo->fd_formb_nsecs);
                        FDC_WRFIFO(fdc, finfo->fd_formb_gaplen);
                        FDC_WRFIFO(fdc, finfo->fd_formb_fillbyte);
                } else {
                        if (read)
                                FDC_WRFIFO(fdc, NE7CMD_READ);
                        else
                                FDC_WRFIFO(fdc, NE7CMD_WRITE);
                        FDC_WRFIFO(fdc, (head << 2) | fd->sc_drive);
                        FDC_WRFIFO(fdc, fd->sc_cylin);  /*track*/
                        FDC_WRFIFO(fdc, head);
                        FDC_WRFIFO(fdc, sec + 1);       /*sector+1*/
                        FDC_WRFIFO(fdc, type->secsize); /*sector size*/
                        FDC_WRFIFO(fdc, type->sectrac); /*secs/track*/
                        FDC_WRFIFO(fdc, type->gap1);    /*gap1 size*/
                        FDC_WRFIFO(fdc, type->datalen); /*data length*/
                }

                return (1);                             /* will return later */

        case SEEKWAIT:
                timeout_del(&fdc->fdctimeout_to);
                fdc->sc_state = SEEKCOMPLETE;
                if (fdc->sc_flags & FDC_NEEDHEADSETTLE) {
                        /* allow 1/50 second for heads to settle */
                        timeout_add_msec(&fdc->fdcpseudointr_to, 20);
                        return (1);             /* will return later */
                }
                /*FALLTHROUGH*/
        case SEEKCOMPLETE:
                /* no data on seek */
                disk_unbusy(&fd->sc_dk, 0, 0, 0);

                /* Make sure seek really happened. */
                if (fdc->sc_nstat != 2 || (st0 & 0xf8) != 0x20 ||
                    cyl != cylin * fd->sc_type->step) {
#ifdef FD_DEBUG
                        if (fdc_debug)
                                fdcstatus(fdc, "seek failed");
#endif
                        fdcretry(fdc);
                        goto loop;
                }
                fd->sc_cylin = cylin;
                goto doio;

        case IOTIMEDOUT:
                /*
                 * Try to abort the I/O operation without resetting
                 * the chip first.  Poke TC and arrange to pick up
                 * the timed out I/O command's status.
                 */
                fdc->sc_itask = FDC_ITASK_RESULT;
                fdc->sc_state = IOCLEANUPWAIT;
                fdc->sc_nstat = 0;
                /* 1/10 second should be enough */
                timeout_add_msec(&fdc->fdctimeout_to, 100);
                return (1);

        case IOCLEANUPTIMEDOUT:
        case SEEKTIMEDOUT:
        case RECALTIMEDOUT:
        case RESETTIMEDOUT:
        case DSKCHGTIMEDOUT:
                fdcstatus(fdc, "timeout");

                /* All other timeouts always roll through to a chip reset */
                fdcretry(fdc);

                /* Force reset, no matter what fdcretry() says */
                fdc->sc_state = DORESET;
                goto loop;

        case IOCLEANUPWAIT: /* IO FAILED, cleanup succeeded */
                timeout_del(&fdc->fdctimeout_to);
                disk_unbusy(&fd->sc_dk, (bp->b_bcount - bp->b_resid),
                    bp->b_blkno, (bp->b_flags & B_READ));
                fdcretry(fdc);
                goto loop;

        case IOCOMPLETE: /* IO DONE, post-analyze */
                timeout_del(&fdc->fdctimeout_to);

                disk_unbusy(&fd->sc_dk, (bp->b_bcount - bp->b_resid),
                    bp->b_blkno, (bp->b_flags & B_READ));

                if (fdc->sc_nstat != 7 || st1 != 0 ||
                    ((st0 & 0xf8) != 0 &&
                     ((st0 & 0xf8) != 0x20 || (fdc->sc_cfg & CFG_EIS) == 0))) {
#ifdef FD_DEBUG
                        if (fdc_debug) {
                                fdcstatus(fdc,
                                        bp->b_flags & B_READ
                                        ? "read failed" : "write failed");
                                printf("blkno %lld nblks %d nstat %d tc %d\n",
                                       (long long)fd->sc_blkno, fd->sc_nblks,
                                       fdc->sc_nstat, fdc->sc_tc);
                        }
#endif
                        if (fdc->sc_nstat == 7 &&
                            (st1 & ST1_OVERRUN) == ST1_OVERRUN) {

                                /*
                                 * Silently retry overruns if no other
                                 * error bit is set. Adjust threshold.
                                 */
                                int thr = fdc->sc_cfg & CFG_THRHLD_MASK;
                                if (thr < 15) {
                                        thr++;
                                        fdc->sc_cfg &= ~CFG_THRHLD_MASK;
                                        fdc->sc_cfg |= (thr & CFG_THRHLD_MASK);
#ifdef FD_DEBUG
                                        if (fdc_debug)
                                                printf("fdc: %d -> threshold\n", thr);
#endif
                                        fdconf(fdc);
                                        fdc->sc_overruns = 0;
                                }
                                if (++fdc->sc_overruns < 3) {
                                        fdc->sc_state = DOIO;
                                        goto loop;
                                }
                        }
                        fdcretry(fdc);
                        goto loop;
                }
                if (fdc->sc_errors) {
                        diskerr(bp, "fd", "soft error", LOG_PRINTF,
                            fd->sc_skip / FD_BSIZE(fd),
                            (struct disklabel *)NULL);
                        printf("\n");
                        fdc->sc_errors = 0;
                } else {
                        if (--fdc->sc_overruns < -20) {
                                int thr = fdc->sc_cfg & CFG_THRHLD_MASK;
                                if (thr > 0) {
                                        thr--;
                                        fdc->sc_cfg &= ~CFG_THRHLD_MASK;
                                        fdc->sc_cfg |= (thr & CFG_THRHLD_MASK);
#ifdef FD_DEBUG
                                        if (fdc_debug)
                                                printf("fdc: %d -> threshold\n", thr);
#endif
                                        fdconf(fdc);
                                }
                                fdc->sc_overruns = 0;
                        }
                }
                fd->sc_blkno += fd->sc_nblks;
                fd->sc_skip += fd->sc_nbytes;
                fd->sc_bcount -= fd->sc_nbytes;
                bp->b_resid -= fd->sc_nbytes;
                if (finfo == NULL && fd->sc_bcount > 0) {
                        cylin = fd->sc_blkno / fd->sc_type->seccyl;
                        goto doseek;
                }
                fdfinish(fd, bp);
                goto loop;

        case DORESET:
                /* try a reset, keep motor on */
                fd_set_motor(fdc);
                delay(100);
                fdc->sc_nstat = 0;
                fdc->sc_itask = FDC_ITASK_SENSEI;
                fdc->sc_state = RESETCOMPLETE;
                timeout_add_msec(&fdc->fdctimeout_to, 500);
                fdc_reset(fdc);
                return (1);                     /* will return later */

        case RESETCOMPLETE:
                timeout_del(&fdc->fdctimeout_to);
                fdconf(fdc);

                /* FALLTHROUGH */
        case DORECAL:
                fdc->sc_state = RECALWAIT;
                fdc->sc_itask = FDC_ITASK_SENSEI;
                fdc->sc_nstat = 0;
                timeout_add_sec(&fdc->fdctimeout_to, 5);
                /* recalibrate function */
                FDC_WRFIFO(fdc, NE7CMD_RECAL);
                FDC_WRFIFO(fdc, fd->sc_drive);
                return (1);                     /* will return later */

        case RECALWAIT:
                timeout_del(&fdc->fdctimeout_to);
                fdc->sc_state = RECALCOMPLETE;
                if (fdc->sc_flags & FDC_NEEDHEADSETTLE) {
                        /* allow 1/30 second for heads to settle */
                        timeout_add_msec(&fdc->fdcpseudointr_to, 1000 / 30);
                        return (1);             /* will return later */
                }

        case RECALCOMPLETE:
                if (fdc->sc_nstat != 2 || (st0 & 0xf8) != 0x20 || cyl != 0) {
#ifdef FD_DEBUG
                        if (fdc_debug)
                                fdcstatus(fdc, "recalibrate failed");
#endif
                        fdcretry(fdc);
                        goto loop;
                }
                fd->sc_cylin = 0;
                goto doseek;

        case MOTORWAIT:
                if (fd->sc_flags & FD_MOTOR_WAIT)
                        return (1);             /* time's not up yet */
                goto doseek;

        default:
                fdcstatus(fdc, "stray interrupt");
                return (1);
        }
#ifdef DIAGNOSTIC
        panic("fdcintr: impossible");
#endif

xxx:
        /*
         * We get here if the chip locks up in FDC_WRFIFO()
         * Cancel any operation and schedule a reset
         */
        timeout_del(&fdc->fdctimeout_to);
        fdcretry(fdc);
        fdc->sc_state = DORESET;
        goto loop;

#undef  st0
#undef  st1
#undef  cyl
}

void
fdcretry(struct fdc_softc *fdc)
{
        struct fd_softc *fd;
        struct buf *bp;
        int error = EIO;

        fd = TAILQ_FIRST(&fdc->sc_drives);
        bp = fd->sc_bp;

        fdc->sc_overruns = 0;
        if (fd->sc_opts & FDOPT_NORETRY)
                goto fail;

        switch (fdc->sc_errors) {
        case 0:
                if (fdc->sc_nstat == 7 &&
                    (fdc->sc_status[0] & 0xd8) == 0x40 &&
                    (fdc->sc_status[1] & 0x2) == 0x2) {
                        printf("%s: read-only medium\n", fd->sc_dv.dv_xname);
                        error = EROFS;
                        goto failsilent;
                }
                /* try again */
                fdc->sc_state =
                    (fdc->sc_flags & FDC_EIS) ? DOIO : DOSEEK;
                break;

        case 1: case 2: case 3:
                /* didn't work; try recalibrating */
                fdc->sc_state = DORECAL;
                break;

        case 4:
                if (fdc->sc_nstat == 7 &&
                    fdc->sc_status[0] == 0 &&
                    fdc->sc_status[1] == 0 &&
                    fdc->sc_status[2] == 0) {
                        /*
                         * We've retried a few times and we've got
                         * valid status and all three status bytes
                         * are zero.  Assume this condition is the
                         * result of no disk loaded into the drive.
                         */
                        printf("%s: no medium?\n", fd->sc_dv.dv_xname);
                        error = ENODEV;
                        goto failsilent;
                }

                /* still no go; reset the bastard */
                fdc->sc_state = DORESET;
                break;

        default:
        fail:
                if ((fd->sc_opts & FDOPT_SILENT) == 0) {
                        diskerr(bp, "fd", "hard error", LOG_PRINTF,
                                fd->sc_skip / FD_BSIZE(fd),
                                (struct disklabel *)NULL);
                        printf("\n");
                        fdcstatus(fdc, "controller status");
                }

        failsilent:
                bp->b_flags |= B_ERROR;
                bp->b_error = error;
                bp->b_resid = bp->b_bcount;
                fdfinish(fd, bp);
        }
        fdc->sc_errors++;
}

daddr_t
fdsize(dev_t dev)
{

        /* Swapping to floppies would not make sense. */
        return (-1);
}

int
fddump(dev_t dev, daddr_t blkno, caddr_t va, size_t size)
{

        /* Not implemented. */
        return (EINVAL);
}

int
fdioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
{
        struct fd_softc *fd;
        struct fdc_softc *fdc;
        struct disklabel *lp;
        int unit;
        int error;
#ifdef FD_DEBUG
        int i;
#endif

        unit = FDUNIT(dev);
        if (unit >= fd_cd.cd_ndevs)
                return (ENXIO);

        fd = fd_cd.cd_devs[FDUNIT(dev)];
        fdc = (struct fdc_softc *)fd->sc_dv.dv_parent;

        switch (cmd) {
        case DIOCRLDINFO:
                lp = malloc(sizeof(*lp), M_TEMP, M_WAITOK);
                fdgetdisklabel(dev, fd, lp, 0);
                bcopy(lp, fd->sc_dk.dk_label, sizeof(*lp));
                free(lp, M_TEMP, 0);
                return 0;

        case DIOCGPDINFO:
                fdgetdisklabel(dev, fd, (struct disklabel *)addr, 1);
                return 0;

        case DIOCGDINFO:
                *(struct disklabel *)addr = *(fd->sc_dk.dk_label);
                return 0;

        case DIOCGPART:
                ((struct partinfo *)addr)->disklab = fd->sc_dk.dk_label;
                ((struct partinfo *)addr)->part =
                    &fd->sc_dk.dk_label->d_partitions[FDPART(dev)];
                return 0;

        case DIOCWDINFO:
        case DIOCSDINFO:
                if ((flag & FWRITE) == 0)
                        return (EBADF);

                error = setdisklabel(fd->sc_dk.dk_label,
                    (struct disklabel *)addr, 0);
                if (error == 0) {
                        if (cmd == DIOCWDINFO)
                                error = writedisklabel(DISKLABELDEV(dev),
                                    fdstrategy, fd->sc_dk.dk_label);
                }
                return (error);

        case DIOCLOCK:
                /*
                 * Nothing to do here, really.
                 */
                return (0);

        case MTIOCTOP:
                if (((struct mtop *)addr)->mt_op != MTOFFL)
                        return (EIO);
                /* FALLTHROUGH */
        case DIOCEJECT:
                if (fdc->sc_flags & FDC_NOEJECT)
                        return (ENODEV);
                fd_do_eject(fd);
                return (0);

        case FD_FORM:
                if ((flag & FWRITE) == 0)
                        return (EBADF); /* must be opened for writing */
                else if (((struct fd_formb *)addr)->format_version !=
                    FD_FORMAT_VERSION)
                        return (EINVAL);/* wrong version of formatting prog */
                else
                        return fdformat(dev, (struct fd_formb *)addr, p);
                break;

        case FD_GTYPE:          /* get drive options */
                *(struct fd_type *)addr = *fd->sc_type;
                return (0);

        case FD_GOPTS:          /* get drive options */
                *(int *)addr = fd->sc_opts;
                return (0);

        case FD_SOPTS:          /* set drive options */
                fd->sc_opts = *(int *)addr;
                return (0);

#ifdef FD_DEBUG
        case _IO('f', 100):
                fdc_wrfifo(fdc, NE7CMD_DUMPREG);
                fdcresult(fdc);
                printf("fdc: dumpreg(%d regs): <", fdc->sc_nstat);
                for (i = 0; i < fdc->sc_nstat; i++)
                        printf(" 0x%x", fdc->sc_status[i]);
                printf(">\n");
                return (0);

        case _IOW('f', 101, int):
                fdc->sc_cfg &= ~CFG_THRHLD_MASK;
                fdc->sc_cfg |= (*(int *)addr & CFG_THRHLD_MASK);
                fdconf(fdc);
                return (0);

        case _IO('f', 102):
                fdc_wrfifo(fdc, NE7CMD_SENSEI);
                fdcresult(fdc);
                printf("fdc: sensei(%d regs): <", fdc->sc_nstat);
                for (i=0; i< fdc->sc_nstat; i++)
                        printf(" 0x%x", fdc->sc_status[i]);
                printf(">\n");
                return (0);
#endif
        default:
                return (ENOTTY);
        }
}

int
fdformat(dev_t dev, struct fd_formb *finfo, struct proc *p)
{
        int rv = 0;
        struct fd_softc *fd = fd_cd.cd_devs[FDUNIT(dev)];
        struct fd_type *type = fd->sc_type;
        struct buf *bp;

        /* set up a buffer header for fdstrategy() */
        bp = malloc(sizeof(*bp), M_TEMP, M_NOWAIT | M_ZERO);
        if (bp == NULL)
                return (ENOBUFS);

        bp->b_flags = B_BUSY | B_PHYS | B_FORMAT | B_RAW;
        bp->b_proc = p;
        bp->b_dev = dev;

        /*
         * Calculate a fake blkno, so fdstrategy() would initiate a
         * seek to the requested cylinder.
         */
        bp->b_blkno = ((finfo->cyl * (type->sectrac * type->heads)
                       + finfo->head * type->sectrac) * FD_BSIZE(fd))
                      / DEV_BSIZE;

        bp->b_bcount = sizeof(struct fd_idfield_data) * finfo->fd_formb_nsecs;
        bp->b_data = (caddr_t)finfo;

#ifdef FD_DEBUG
        if (fdc_debug) {
                int i;

                printf("fdformat: blkno 0x%llx count %ld\n",
                        (unsigned long long)bp->b_blkno, bp->b_bcount);

                printf("\tcyl:\t%d\n", finfo->cyl);
                printf("\thead:\t%d\n", finfo->head);
                printf("\tnsecs:\t%d\n", finfo->fd_formb_nsecs);
                printf("\tsshft:\t%d\n", finfo->fd_formb_secshift);
                printf("\tgaplen:\t%d\n", finfo->fd_formb_gaplen);
                printf("\ttrack data:");
                for (i = 0; i < finfo->fd_formb_nsecs; i++) {
                        printf(" [c%d h%d s%d]",
                                        finfo->fd_formb_cylno(i),
                                        finfo->fd_formb_headno(i),
                                        finfo->fd_formb_secno(i) );
                        if (finfo->fd_formb_secsize(i) != 2)
                                printf("<sz:%d>", finfo->fd_formb_secsize(i));
                }
                printf("\n");
        }
#endif

        /* now do the format */
        fdstrategy(bp);

        /* ...and wait for it to complete */
        rv = biowait(bp);
        free(bp, M_TEMP, 0);
        return (rv);
}

int
fdgetdisklabel(dev_t dev, struct fd_softc *fd, struct disklabel *lp,
    int spoofonly)
{
        bzero(lp, sizeof(struct disklabel));

        lp->d_type = DTYPE_FLOPPY;
        lp->d_secsize = FD_BSIZE(fd);
        lp->d_secpercyl = fd->sc_type->seccyl;
        lp->d_nsectors = fd->sc_type->sectrac;
        lp->d_ncylinders = fd->sc_type->tracks;
        lp->d_ntracks = fd->sc_type->heads;     /* Go figure... */
        DL_SETDSIZE(lp, (u_int64_t)lp->d_secpercyl * lp->d_ncylinders);

        strncpy(lp->d_typename, "floppy disk", sizeof(lp->d_typename));
        strncpy(lp->d_packname, "fictitious", sizeof(lp->d_packname));
        lp->d_version = 1;

        lp->d_magic = DISKMAGIC;
        lp->d_magic2 = DISKMAGIC;
        lp->d_checksum = dkcksum(lp);

        /*
         * Call the generic disklabel extraction routine.  If there's
         * not a label there, fake it.
         */
        return readdisklabel(DISKLABELDEV(dev), fdstrategy, lp, spoofonly);
}

void
fd_do_eject(struct fd_softc *fd)
{
        struct fdc_softc *fdc = (void *)fd->sc_dv.dv_parent;
        bus_space_tag_t t = fdc->sc_bustag;
        bus_space_handle_t h = fdc->sc_handle;
        u_int8_t dor = FDO_FRST | FDO_FDMAEN | FDO_MOEN(0);

        bus_space_write_1(t, h, FDREG77_DOR, dor | FDO_EJ);
        delay(10);
        bus_space_write_1(t, h, FDREG77_DOR, FDO_FRST | FDO_DS);
}