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[netbsd-mini2440.git] / sys / arch / arc / jazz / fd.c

/*      $NetBSD: fd.c,v 1.39 2009/01/13 13:35:51 yamt Exp $     */
/*      $OpenBSD: fd.c,v 1.6 1998/10/03 21:18:57 millert Exp $  */
/*      NetBSD: fd.c,v 1.78 1995/07/04 07:23:09 mycroft Exp     */

/*-
 * Copyright (c) 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles M. Hannum.
 *
 * 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
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: fd.c,v 1.39 2009/01/13 13:35:51 yamt Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/callout.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/device.h>
#include <sys/disklabel.h>
#include <sys/disk.h>
#include <sys/buf.h>
#include <sys/bufq.h>
#include <sys/uio.h>
#include <sys/syslog.h>
#include <sys/queue.h>

#include <uvm/uvm_extern.h>

#include <dev/cons.h>

#include <machine/bus.h>
#include <machine/cpu.h>

#include <arc/jazz/fdreg.h>
#include <arc/jazz/fdcvar.h>

#include "ioconf.h"
#include "locators.h"

#define FDUNIT(dev)     DISKUNIT(dev)
#define FDTYPE(dev)     DISKPART(dev)

/* controller driver configuration */
static int fdprint(void *, const char *);

/*
 * Floppies come in various flavors, e.g., 1.2MB vs 1.44MB; here is how
 * we tell them apart.
 */
struct fd_type {
        int     sectrac;        /* sectors per track */
        int     heads;          /* number of heads */
        int     seccyl;         /* sectors per cylinder */
        int     secsize;        /* size code for sectors */
        int     datalen;        /* data len when secsize = 0 */
        int     steprate;       /* step rate and head unload time */
        int     gap1;           /* gap len between sectors */
        int     gap2;           /* formatting gap */
        int     cyls;           /* total num of cylinders */
        int     size;           /* size of disk in sectors */
        int     step;           /* steps per cylinder */
        int     rate;           /* transfer speed code */
        const char *name;
};

/* The order of entries in the following table is important -- BEWARE! */
const static struct fd_type fd_types[] = {
        /* 1.44MB diskette */
        { 18,2,36,2,0xff,0xcf,0x1b,0x6c,80,2880,1,FDC_500KBPS,"1.44MB"    },
        /* 1.2 MB AT-diskettes */
        { 15,2,30,2,0xff,0xdf,0x1b,0x54,80,2400,1,FDC_500KBPS, "1.2MB"    },
        /* 360kB in 1.2MB drive */
        {  9,2,18,2,0xff,0xdf,0x23,0x50,40, 720,2,FDC_300KBPS, "360KB/AT" },
        /* 360kB PC diskettes */
        {  9,2,18,2,0xff,0xdf,0x2a,0x50,40, 720,1,FDC_250KBPS, "360KB/PC" },
        /* 3.5" 720kB diskette */
        {  9,2,18,2,0xff,0xdf,0x2a,0x50,80,1440,1,FDC_250KBPS, "720KB"    },
        /* 720kB in 1.2MB drive */
        {  9,2,18,2,0xff,0xdf,0x23,0x50,80,1440,1,FDC_300KBPS, "720KB/x"  },
        /* 360kB in 720kB drive */
        {  9,2,18,2,0xff,0xdf,0x2a,0x50,40, 720,2,FDC_250KBPS, "360KB/x"  },
};

/* software state, per disk (with up to 4 disks per ctlr) */
struct fd_softc {
        device_t sc_dev;
        struct disk sc_dk;

        const struct fd_type *sc_deftype; /* default type descriptor */
        struct fd_type *sc_type;        /* current type descriptor */
        struct fd_type sc_type_copy;    /* copy for fiddling when formatting */

        struct callout sc_motoron_ch;
        struct callout sc_motoroff_ch;

        daddr_t sc_blkno;       /* starting block number */
        int sc_bcount;          /* byte count left */
        int sc_opts;            /* user-set options */
        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 */

        TAILQ_ENTRY(fd_softc) sc_drivechain;
        int sc_ops;             /* I/O ops since last switch */
        struct bufq_state *sc_q;/* pending I/O requests */
        int sc_active;          /* number of active I/O operations */
};

/* floppy driver configuration */
static int fdprobe(device_t, cfdata_t, void *);
static void fdattach(device_t, device_t, void *);

CFATTACH_DECL_NEW(fd, sizeof(struct fd_softc), fdprobe, fdattach, NULL, NULL);

dev_type_open(fdopen);
dev_type_close(fdclose);
dev_type_read(fdread);
dev_type_write(fdwrite);
dev_type_ioctl(fdioctl);
dev_type_strategy(fdstrategy);

const struct bdevsw fd_bdevsw = {
        fdopen, fdclose, fdstrategy, fdioctl, nodump, nosize, D_DISK
};

const struct cdevsw fd_cdevsw = {
        fdopen, fdclose, fdread, fdwrite, fdioctl,
        nostop, notty, nopoll, nommap, nokqfilter, D_DISK
};

static void fdstart(struct fd_softc *);

struct dkdriver fddkdriver = { fdstrategy };

static bool fd_shutdown(device_t, int);
#if 0
static const struct fd_type *fd_nvtotype(char *, int, int);
#endif
static void fd_set_motor(struct fdc_softc *, int);
static void fd_motor_off(void *);
static void fd_motor_on(void *);
static int fdcresult(struct fdc_softc *);
static void fdcstart(struct fdc_softc *);
static void fdcstatus(device_t, int, const char *);
static void fdctimeout(void *);
static void fdcpseudointr(void *);
static void fdcretry(struct fdc_softc *);
static void fdfinish(struct fd_softc *, struct buf *);
static inline const struct fd_type *fd_dev_to_type(struct fd_softc *, dev_t);
static void fd_mountroot_hook(device_t);

/*
 * Arguments passed between fdcattach and fdprobe.
 */
struct fdc_attach_args {
        int fa_drive;
        const 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.
 */
static int
fdprint(void *aux, const char *fdc)
{
        struct fdc_attach_args *fa = aux;

        if (fdc == NULL)
                aprint_normal(" drive %d", fa->fa_drive);
        return QUIET;
}

void
fdcattach(struct fdc_softc *fdc)
{
        struct fdc_attach_args fa;
        bus_space_tag_t iot;
        bus_space_handle_t ioh;
        int type;

        iot = fdc->sc_iot;
        ioh = fdc->sc_ioh;
        callout_init(&fdc->sc_timo_ch, 0);
        callout_init(&fdc->sc_intr_ch, 0);

        fdc->sc_state = DEVIDLE;
        TAILQ_INIT(&fdc->sc_drives);

        /*
         * No way yet to determine default disk types.
         * we assume 1.44 3.5" type for the moment.
         */
        type = 0;

        /* physical limit: two drives per controller. */
        for (fa.fa_drive = 0; fa.fa_drive < 2; fa.fa_drive++) {
                fa.fa_deftype = &fd_types[type];
                (void)config_found(fdc->sc_dev, (void *)&fa, fdprint);
        }
}

static int
fdprobe(device_t parent, cfdata_t cf , void *aux)
{
        struct fdc_softc *fdc = device_private(parent);
        struct fdc_attach_args *fa = aux;
        int drive = fa->fa_drive;
        bus_space_tag_t iot = fdc->sc_iot;
        bus_space_handle_t ioh = fdc->sc_ioh;
        int n;

        if (cf->cf_loc[FDCCF_DRIVE] != FDCCF_DRIVE_DEFAULT &&
            cf->cf_loc[FDCCF_DRIVE] != drive)
                return 0;

        /* select drive and turn on motor */
        bus_space_write_1(iot, ioh, FDOUT, drive | FDO_FRST | FDO_MOEN(drive));
        /* wait for motor to spin up */
        delay(250000);
        out_fdc(iot, ioh, NE7CMD_RECAL);
        out_fdc(iot, ioh, drive);
        /* wait for recalibrate */
        delay(2000000);
        out_fdc(iot, ioh, NE7CMD_SENSEI);
        n = fdcresult(fdc);
#ifdef FD_DEBUG
        {
                int i;
                aprint_debug("%s: status", __func__);
                for (i = 0; i < n; i++)
                        aprint_debug(" %x", fdc->sc_status[i]);
                aprint_debug("\n");
        }
#endif
        if (n != 2 || (fdc->sc_status[0] & 0xf8) != 0x20)
                return 0;
        /* turn off motor */
        bus_space_write_1(iot, ioh, FDOUT, FDO_FRST);

        return 1;
}

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

        fd->sc_dev = self;

        callout_init(&fd->sc_motoron_ch, 0);
        callout_init(&fd->sc_motoroff_ch, 0);

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

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

        bufq_alloc(&fd->sc_q, "disksort", BUFQ_SORT_CYLINDER);
        fd->sc_cylin = -1;
        fd->sc_drive = drive;
        fd->sc_deftype = type;
        fdc->sc_fd[drive] = fd;

        /*
         * Initialize and attach the disk structure.
         */
        disk_init(&fd->sc_dk, device_xname(fd->sc_dev), &fddkdriver);
        disk_attach(&fd->sc_dk);

        /* Establish a mountroot hook. */
        mountroothook_establish(fd_mountroot_hook, fd->sc_dev);

        /* Needed to power off if the motor is on when we halt. */
        if (!pmf_device_register1(self, NULL, NULL, fd_shutdown))
                aprint_error_dev(self, "couldn't establish power handler\n");
}

bool
fd_shutdown(device_t self, int howto)
{
        struct fd_softc *fd;

        fd = device_private(self);
        fd_motor_off(fd);

        return true;
}

#if 0
/*
 * Translate nvram type into internal data structure.  Return NULL for
 * none/unknown/unusable.
 */
static const struct fd_type *
fd_nvtotype(char *fdc, int nvraminfo, int drive)
{
        int type;

        type = (drive == 0 ? nvraminfo : nvraminfo << 4) & 0xf0;
#if 0
        switch (type) {
        case NVRAM_DISKETTE_NONE:
                return NULL;
        case NVRAM_DISKETTE_12M:
                return &fd_types[1];
        case NVRAM_DISKETTE_TYPE5:
        case NVRAM_DISKETTE_TYPE6:
                /* XXX We really ought to handle 2.88MB format. */
        case NVRAM_DISKETTE_144M:
                return &fd_types[0];
        case NVRAM_DISKETTE_360K:
                return &fd_types[3];
        case NVRAM_DISKETTE_720K:
                return &fd_types[4];
        default:
                printf("%s: drive %d: unknown device type 0x%x\n",
                    fdc, drive, type);
                return NULL;
        }
#else
        return &fd_types[0]; /* Use only 1.44 for now */
#endif
}
#endif

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

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

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

        /* Valid unit, controller, and request? */
        if (bp->b_blkno < 0 ||
            (bp->b_bcount % FDC_BSIZE) != 0) {
                bp->b_error = EINVAL;
                goto done;
        }

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

        sz = howmany(bp->b_bcount, FDC_BSIZE);

        if (bp->b_blkno + sz > fd->sc_type->size) {
                sz = fd->sc_type->size - 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 done;
                }
                /* Otherwise, truncate request. */
                bp->b_bcount = sz << DEV_BSHIFT;
        }

        bp->b_rawblkno = bp->b_blkno;
        bp->b_cylinder =
            bp->b_blkno / (FDC_BSIZE / DEV_BSIZE) / fd->sc_type->seccyl;

#ifdef FD_DEBUG
        printf("%s: b_blkno %" PRId64 " b_bcount %ld blkno %" PRId64
            " cylin %ld sz %d\n", __func__,
            bp->b_blkno, bp->b_bcount, fd->sc_blkno, bp->b_cylinder, sz);
#endif

        /* Queue transfer on drive, activate drive and controller if idle. */
        s = splbio();
        bufq_put(fd->sc_q, bp);
        callout_stop(&fd->sc_motoroff_ch);              /* a good idea */
        if (fd->sc_active == 0)
                fdstart(fd);
#ifdef DIAGNOSTIC
        else {
                struct fdc_softc *fdc =
                    device_private(device_parent(fd->sc_dev));
                if (fdc->sc_state == DEVIDLE) {
                        printf("%s: controller inactive\n", __func__);
                        fdcstart(fdc);
                }
        }
#endif
        splx(s);
        return;

 done:
        /* Toss transfer; we're done early. */
        bp->b_resid = bp->b_bcount;
        biodone(bp);
}

void
fdstart(struct fd_softc *fd)
{
        struct fdc_softc *fdc = device_private(device_parent(fd->sc_dev));
        int active = TAILQ_FIRST(&fdc->sc_drives) != 0;

        /* Link into controller queue. */
        fd->sc_active = 1;
        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 = device_private(device_parent(fd->sc_dev));

        /*
         * 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.
         */
        (void)bufq_get(fd->sc_q);
        if (TAILQ_NEXT(fd, sc_drivechain) && ++fd->sc_ops >= 8) {
                fd->sc_ops = 0;
                TAILQ_REMOVE(&fdc->sc_drives, fd, sc_drivechain);
                if (bufq_peek(fd->sc_q) != NULL)
                        TAILQ_INSERT_TAIL(&fdc->sc_drives, fd, sc_drivechain);
                else
                        fd->sc_active = 0;
        }
        bp->b_resid = fd->sc_bcount;
        fd->sc_skip = 0;
        biodone(bp);
        /* turn off motor 5s from now */
        callout_reset(&fd->sc_motoroff_ch, 5 * hz, fd_motor_off, fd);
        fdc->sc_state = DEVIDLE;
}

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

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

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

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

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

        if ((fd = TAILQ_FIRST(&fdc->sc_drives)) != NULL)
                status = fd->sc_drive;
        else
                status = 0;
        if (!reset)
                status |= FDO_FRST | FDO_FDMAEN;
        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_iot, fdc->sc_ioh, FDOUT, status);
}

void
fd_motor_off(void *arg)
{
        struct fd_softc *fd = arg;
        struct fdc_softc *fdc = device_private(device_parent(fd->sc_dev));
        int s;

        s = splbio();
        fd->sc_flags &= ~(FD_MOTOR | FD_MOTOR_WAIT);
        fd_set_motor(fdc, 0);
        splx(s);
}

void
fd_motor_on(void *arg)
{
        struct fd_softc *fd = arg;
        struct fdc_softc *fdc = device_private(device_parent(fd->sc_dev));
        int s;

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

int
fdcresult(struct fdc_softc *fdc)
{
        bus_space_tag_t iot = fdc->sc_iot;
        bus_space_handle_t ioh = fdc->sc_ioh;
        u_char i;
        int j, n = 0;

        for (j = 100000; j; j--) {
                i = bus_space_read_1(iot, ioh, FDSTS) &
                    (NE7_DIO | NE7_RQM | NE7_CB);
                if (i == NE7_RQM)
                        return n;
                if (i == (NE7_DIO | NE7_RQM | NE7_CB)) {
                        if (n >= sizeof(fdc->sc_status)) {
                                log(LOG_ERR, "%s: overrun\n", __func__);
                                return -1;
                        }
                        fdc->sc_status[n++] =
                            bus_space_read_1(iot, ioh, FDDATA);
                }
                delay(10);
        }
        log(LOG_ERR, "%s: timeout\n", __func__);
        return -1;
}

int
out_fdc(bus_space_tag_t iot, bus_space_handle_t ioh, uint8_t x)
{
        int i = 100000;

        while ((bus_space_read_1(iot, ioh, FDSTS) & NE7_DIO) && i-- > 0);
        if (i <= 0)
                return -1;
        while ((bus_space_read_1(iot, ioh, FDSTS) & NE7_RQM) == 0 && i-- > 0);
        if (i <= 0)
                return -1;
        bus_space_write_1(iot, ioh, FDDATA, x);
        return 0;
}

int
fdopen(dev_t dev, int flags, int mode, struct lwp *l)
{
        struct fd_softc *fd;
        const struct fd_type *type;

        fd = device_lookup_private(&fd_cd, FDUNIT(dev));
        if (fd == NULL)
                return ENXIO;

        type = fd_dev_to_type(fd, dev);
        if (type == NULL)
                return ENXIO;

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

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

        return 0;
}

int
fdclose(dev_t dev, int flags, int mode, struct lwp *l)
{
        struct fd_softc *fd = device_lookup_private(&fd_cd, FDUNIT(dev));

        fd->sc_flags &= ~FD_OPEN;
        return 0;
}

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("%s: not idle\n", __func__);
                return;
        }
#endif
        (void)fdcintr(fdc);
}

static void
fdcpstatus(int n, struct fdc_softc *fdc)
{
        char bits[64];

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

void
fdcstatus(device_t dev, int n, const char *s)
{
        struct fdc_softc *fdc = device_private(device_parent(dev));

        if (n == 0) {
                out_fdc(fdc->sc_iot, fdc->sc_ioh, NE7CMD_SENSEI);
                (void)fdcresult(fdc);
                n = 2;
        }

        printf("%s: %s", device_xname(dev), s);
        fdcpstatus(n, fdc);
}

void
fdctimeout(void *arg)
{
        struct fdc_softc *fdc = arg;
        struct fd_softc *fd = TAILQ_FIRST(&fdc->sc_drives);
        int s;

        s = splbio();
#ifdef DEBUG
        log(LOG_ERR, "%s: state %d\n", __func__, fdc->sc_state);
#endif
        fdcstatus(fd->sc_dev, 0, "timeout");

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

        (void)fdcintr(fdc);
        splx(s);
}

void
fdcpseudointr(void *arg)
{
        int s;

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

int
fdcintr(void *arg)
{
        struct fdc_softc *fdc = arg;
#define st0     fdc->sc_status[0]
#define cyl     fdc->sc_status[1]
        struct fd_softc *fd;
        struct buf *bp;
        bus_space_tag_t iot = fdc->sc_iot;
        bus_space_handle_t ioh = fdc->sc_ioh;
        int read, head, sec, i, nblks;
        struct fd_type *type;

 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 1;
        }

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

        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 / (FDC_BSIZE / DEV_BSIZE);
                callout_stop(&fd->sc_motoroff_ch);
                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) {
                                callout_stop(&ofd->sc_motoroff_ch);
                                ofd->sc_flags &= ~(FD_MOTOR | FD_MOTOR_WAIT);
                        }
                        fd->sc_flags |= FD_MOTOR | FD_MOTOR_WAIT;
                        fd_set_motor(fdc, 0);
                        fdc->sc_state = MOTORWAIT;
                        /* Allow .25s for motor to stabilize. */
                        callout_reset(&fd->sc_motoron_ch, hz / 4,
                            fd_motor_on, fd);
                        return 1;
                }
                /* Make sure the right drive is selected. */
                fd_set_motor(fdc, 0);

                /* fall through */
        case DOSEEK:
 doseek:
                if (fd->sc_cylin == bp->b_cylinder)
                        goto doio;

                out_fdc(iot, ioh, NE7CMD_SPECIFY);/* specify command */
                out_fdc(iot, ioh, fd->sc_type->steprate);
                out_fdc(iot, ioh, 6);           /* XXX head load time == 6ms */

                out_fdc(iot, ioh, NE7CMD_SEEK); /* seek function */
                out_fdc(iot, ioh, fd->sc_drive); /* drive number */
                out_fdc(iot, ioh, bp->b_cylinder * fd->sc_type->step);

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

                iostat_seek(fd->sc_dk.dk_stats);
                disk_busy(&fd->sc_dk);

                callout_reset(&fdc->sc_timo_ch, 4 * hz, fdctimeout, fdc);
                return 1;

        case DOIO:
 doio:
                type = fd->sc_type;
                sec = fd->sc_blkno % type->seccyl;
                nblks = type->seccyl - sec;
                nblks = min(nblks, fd->sc_bcount / FDC_BSIZE);
                nblks = min(nblks, fdc->sc_maxiosize / FDC_BSIZE);
                fd->sc_nblks = nblks;
                fd->sc_nbytes = nblks * FDC_BSIZE;
                head = sec / type->sectrac;
                sec -= head * type->sectrac;
#ifdef DIAGNOSTIC
                {
                        int block;
                        block = (fd->sc_cylin * type->heads + head) *
                            type->sectrac + sec;
                        if (block != fd->sc_blkno) {
                                printf("%s: block %d != blkno %" PRId64
                                    "\n", __func__, block, fd->sc_blkno);
#ifdef DDB
                                 Debugger();
#endif
                        }
                }
#endif
                read = (bp->b_flags & B_READ) != 0;
                FDCDMA_START(fdc, (uint8_t *)bp->b_data + fd->sc_skip,
                    fd->sc_nbytes, read);
                bus_space_write_1(iot, ioh, FDCTL, type->rate);
#ifdef FD_DEBUG
                printf("%s: %s drive %d track %d head %d sec %d nblks %d\n",
                    __func__, read ? "read" : "write", fd->sc_drive,
                    fd->sc_cylin, head, sec, nblks);
#endif
                if (read)
                        out_fdc(iot, ioh, NE7CMD_READ); /* READ */
                else
                        out_fdc(iot, ioh, NE7CMD_WRITE);/* WRITE */
                out_fdc(iot, ioh, (head << 2) | fd->sc_drive);
                out_fdc(iot, ioh, fd->sc_cylin);        /* track */
                out_fdc(iot, ioh, head);
                out_fdc(iot, ioh, sec + 1);             /* sector + 1 */
                out_fdc(iot, ioh, type->secsize);       /* sector size */
                out_fdc(iot, ioh, type->sectrac);       /* sectors/track */
                out_fdc(iot, ioh, type->gap1);          /* gap1 size */
                out_fdc(iot, ioh, type->datalen);       /* data length */
                fdc->sc_state = IOCOMPLETE;

                disk_busy(&fd->sc_dk);

                /* allow 2 seconds for operation */
                callout_reset(&fdc->sc_timo_ch, 2 * hz, fdctimeout, fdc);
                return 1;                               /* will return later */

        case SEEKWAIT:
                callout_stop(&fdc->sc_timo_ch);
                fdc->sc_state = SEEKCOMPLETE;
                /* allow 1/50 second for heads to settle */
                callout_reset(&fdc->sc_intr_ch, hz / 50, fdcpseudointr, fdc);
                return 1;

        case SEEKCOMPLETE:
                disk_unbusy(&fd->sc_dk, 0, 0);

                /* Make sure seek really happened. */
                out_fdc(iot, ioh, NE7CMD_SENSEI);
                if (fdcresult(fdc) != 2 || (st0 & 0xf8) != 0x20 ||
                    cyl != bp->b_cylinder * fd->sc_type->step) {
#ifdef FD_DEBUG
                        fdcstatus(fd->sc_dev, 2, "seek failed");
#endif
                        fdcretry(fdc);
                        goto loop;
                }
                fd->sc_cylin = bp->b_cylinder;
                goto doio;

        case IOTIMEDOUT:
                FDCDMA_ABORT(fdc);

        case SEEKTIMEDOUT:
        case RECALTIMEDOUT:
        case RESETTIMEDOUT:
                fdcretry(fdc);
                goto loop;

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

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

                i = fdcresult(fdc);
                if (i != 7 || (st0 & 0xf8) != 0) {
                        FDCDMA_ABORT(fdc);
#ifdef FD_DEBUG
                        fdcstatus(fd->sc_dev, 7, bp->b_flags & B_READ ?
                            "read failed" : "write failed");
                        printf("blkno %" PRId64 " nblks %d\n",
                            fd->sc_blkno, fd->sc_nblks);
#endif
                        fdcretry(fdc);
                        goto loop;
                }
                FDCDMA_DONE(fdc);
                if (fdc->sc_errors) {
                        diskerr(bp, "fd", "soft error (corrected)", LOG_PRINTF,
                            fd->sc_skip / FDC_BSIZE, NULL);
                        printf("\n");
                        fdc->sc_errors = 0;
                }
                fd->sc_blkno += fd->sc_nblks;
                fd->sc_skip += fd->sc_nbytes;
                fd->sc_bcount -= fd->sc_nbytes;
                if (fd->sc_bcount > 0) {
                        bp->b_cylinder = 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, 1);
                delay(100);
                fd_set_motor(fdc, 0);
                fdc->sc_state = RESETCOMPLETE;
                callout_reset(&fdc->sc_timo_ch, hz / 2, fdctimeout, fdc);
                return 1;                       /* will return later */

        case RESETCOMPLETE:
                callout_stop(&fdc->sc_timo_ch);
                /* clear the controller output buffer */
                for (i = 0; i < 4; i++) {
                        out_fdc(iot, ioh, NE7CMD_SENSEI);
                        (void)fdcresult(fdc);
                }

                /* fall through */
        case DORECAL:
                out_fdc(iot, ioh, NE7CMD_RECAL); /* recalibrate function */
                out_fdc(iot, ioh, fd->sc_drive);
                fdc->sc_state = RECALWAIT;
                callout_reset(&fdc->sc_timo_ch, 5 * hz, fdctimeout, fdc);
                return 1;                       /* will return later */

        case RECALWAIT:
                callout_stop(&fdc->sc_timo_ch);
                fdc->sc_state = RECALCOMPLETE;
                /* allow 1/30 second for heads to settle */
                callout_reset(&fdc->sc_intr_ch, hz / 30, fdcpseudointr, fdc);
                return 1;                       /* will return later */

        case RECALCOMPLETE:
                out_fdc(iot, ioh, NE7CMD_SENSEI);
                if (fdcresult(fdc) != 2 || (st0 & 0xf8) != 0x20 || cyl != 0) {
#ifdef FD_DEBUG
                        fdcstatus(fd->sc_dev, 2, "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(fd->sc_dev, 0, "stray interrupt");
                return 1;
        }
#ifdef DIAGNOSTIC
        panic("%s: impossible", __func__);
#endif
#undef  st0
#undef  cyl
}

void
fdcretry(struct fdc_softc *fdc)
{
        struct fd_softc *fd;
        struct buf *bp;

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

        switch (fdc->sc_errors) {
        case 0:
                /* try again */
                fdc->sc_state = DOSEEK;
                break;

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

        case 4:
                /* still no go; reset the bastard */
                fdc->sc_state = DORESET;
                break;

        default:
                diskerr(bp, "fd", "hard error", LOG_PRINTF,
                    fd->sc_skip / FDC_BSIZE, (struct disklabel *)NULL);

                fdcpstatus(7, fdc);
                bp->b_error = EIO;
                fdfinish(fd, bp);
        }
        fdc->sc_errors++;
}

int
fdioctl(dev_t dev, u_long cmd, void *addr, int flag, struct lwp *l)
{
        struct fd_softc *fd = device_lookup_private(&fd_cd, FDUNIT(dev));
        struct disklabel buffer;
        int error;

        switch (cmd) {
        case DIOCGDINFO:
                memset(&buffer, 0, sizeof(buffer));

                buffer.d_secpercyl = fd->sc_type->seccyl;
                buffer.d_type = DTYPE_FLOPPY;
                buffer.d_secsize = FDC_BSIZE;

                if (readdisklabel(dev, fdstrategy, &buffer, NULL) != NULL)
                        return EINVAL;

                *(struct disklabel *)addr = buffer;
                return 0;

        case DIOCWLABEL:
                if ((flag & FWRITE) == 0)
                        return EBADF;
                /* XXX do something */
                return 0;

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

                error = setdisklabel(&buffer, (struct disklabel *)addr,
                    0, NULL);
                if (error)
                        return error;

                error = writedisklabel(dev, fdstrategy, &buffer, NULL);
                return error;

        default:
                return ENOTTY;
        }

#ifdef DIAGNOSTIC
        panic("%s: impossible", __func__);
#endif
}

/*
 * Mountroot hook: prompt the user to enter the root file system floppy.
 */
void
fd_mountroot_hook(device_t dev)
{
        int c;

        printf("Insert filesystem floppy and press return.");
        cnpollc(1);
        for (;;) {
                c = cngetc();
                if ((c == '\r') || (c == '\n')) {
                        printf("\n");
                        break;
                }
        }
        cnpollc(0);
}